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Sample records for plasma ion implantation

  1. Diagnostic characterization of ablation plasma ion implantation

    NASA Astrophysics Data System (ADS)

    Qi, B.; Gilgenbach, R. M.; Jones, M. C.; Johnston, M. D.; Lau, Y. Y.; Wang, L. M.; Lian, J.; Doll, G. L.; Lazarides, A.

    2003-06-01

    Experiments are reported in which two configurations for ablation-plasma-ion-implantation (APII) are characterized by diagnostics and compared. The first configuration oriented the target parallel to the deposition substrate. This orientation yielded ion-beam-assisted deposition of thin films. A delay (>5 μs) between laser and high voltage was necessary for this geometry to avoid arcing between negatively biased substrate and target. The second experimental configuration oriented the target perpendicular to the deposition substrate, reducing arcing, even for zero/negative delay between the laser and the high voltage pulse. This orientation also reduced neutral atom, ballistic deposition on the substrate resulting in a pure ion implantation mode. Ion density measurements were made by resonant laser diagnostics and Langmuir probes, yielding total ion populations in the range of 1014. Implanted ion doses were estimated by electrical diagnostics, and materials analysis, including x-ray energy dispersive spectroscopy and x-ray photoelectron spectroscopy, yielding implanted doses in the range 1012 ions/cm2 per pulse. This yields an APII efficiency of order 10% for implantation of laser ablated ions. Scaling of ion dose with voltage agrees well with a theory assuming the Child-Langmuir law and that the ion current at the sheath edge is due to the uncovering of the ions by the movement of the sheath. Thin film analysis showed excellent adhesion with smoother films for an accelerating voltage of -3.2 kV; higher voltages (-7.7 kV) roughened the film.

  2. Plasma immersion ion implantation for reducing metal ion release

    NASA Astrophysics Data System (ADS)

    Díaz, C.; García, J. A.; Mändl, S.; Pereiro, R.; Fernández, B.; Rodríguez, R. J.

    2012-11-01

    Plasma immersion ion implantation of Nitrogen and Oxygen on CoCrMo alloys was carried out to improve the tribological and corrosion behaviors of these biomedical alloys. In order to optimize the implantation results we were carried experiments at different temperatures. Tribocorrosion tests in bovine serum were used to measure Co, Cr and Mo releasing by using Inductively Coupled Plasma Mass Spectrometry analysis after tests. Also, X-ray Diffraction analysis were employed in order to explain any obtained difference in wear rate and corrosion tests. Wear tests reveals important decreases in rate of more than one order of magnitude for the best treatment. Moreover decreases in metal release were found for all the implanted samples, preserving the same corrosion resistance of the unimplanted samples. Finally this paper gathers an analysis, in terms of implantation parameters and achieved properties for industrial implementation of these treatments.

  3. Plasma immersion ion implantation for reducing metal ion release

    SciTech Connect

    Diaz, C.; Garcia, J. A.; Maendl, S.; Pereiro, R.; Fernandez, B.; Rodriguez, R. J.

    2012-11-06

    Plasma immersion ion implantation of Nitrogen and Oxygen on CoCrMo alloys was carried out to improve the tribological and corrosion behaviors of these biomedical alloys. In order to optimize the implantation results we were carried experiments at different temperatures. Tribocorrosion tests in bovine serum were used to measure Co, Cr and Mo releasing by using Inductively Coupled Plasma Mass Spectrometry analysis after tests. Also, X-ray Diffraction analysis were employed in order to explain any obtained difference in wear rate and corrosion tests. Wear tests reveals important decreases in rate of more than one order of magnitude for the best treatment. Moreover decreases in metal release were found for all the implanted samples, preserving the same corrosion resistance of the unimplanted samples. Finally this paper gathers an analysis, in terms of implantation parameters and achieved properties for industrial implementation of these treatments.

  4. Plasma etching of ion-implanted polysilicon

    SciTech Connect

    Karulkar, P.C.; Wirzbicki, M.A.

    1989-09-01

    Ion implantation is increasingly used to dope polysilicon gates to obtain lower resistivities and also to control the cumulative time-temperature cycling of VLSI wafers. Dry etching of polysilicon doped with phosphorus by ion implantation was studied using a parallel-plate etcher and two different etch chemistries sulfur haxafluoride-O{sub 2}-argon and SF6-CCl2F2-Ar. These two etch procedures were previously found to result in excellent etching of polysilicon which was doped with phosphorus by solid-source diffusion. Large differences in the cross-sectional profiles of ion-implanted polysilicon were found while using the two chemistries. SF6-dichlorodifluoromethane-Ar chemistry caused sharp notch-like undercuts, while the SF6-O2-Ar chemistry exhibited linewidth loss without any notching. Examples of the cross sections of ion-implanted polysilicon are presented along with a discussion of the possible mechanisms that cause the different cross-sectional profiles in the two etch chemistries. The notching is explained in terms of the variation in the dopant concentration and in the structure of ion-implanted polysilicon at different depths. The absence of notching in the cross section of ion-implanted polysilicon etched in the SF6-O2-Ar chemistry is explained by proposing that the interaction of oxygen in the SF6-O2-Ar chemistry with the etched surface makes the chemistry less sensitive to the dopant concentration in the etched material. Results of a simple experiment which support the proposed explanation are presented.

  5. Improved ion implant fluence uniformity in hydrogen enhanced glow discharge plasma immersion ion implantation into silicon

    SciTech Connect

    Luo, J.; Li, L. H. E-mail: paul.chu@cityu.edu.hk; Liu, H. T.; Xu, Y.; Zuo, X. J.; Zhu, P. Z.; Ma, Y. F.; Yu, K. M.; Fu, Ricky K. Y.; Chu, Paul K. E-mail: paul.chu@cityu.edu.hk

    2014-06-15

    Enhanced glow discharge plasma immersion ion implantation does not require an external plasma source but ion focusing affects the lateral ion fluence uniformity, thereby hampering its use in high-fluence hydrogen ion implantation for thin film transfer and fabrication of silicon-on-insulator. Insertion of a metal ring between the sample stage and glass chamber improves the ion uniformity and reduces the ion fluence non-uniformity as the cathode voltage is raised. Two-dimensional multiple-grid particle-in-cell simulation confirms that the variation of electric field inside the chamber leads to mitigation of the ion focusing phenomenon and the results are corroborated experimentally by hydrogen forward scattering.

  6. Ge laser-generated plasma for ion implantation

    NASA Astrophysics Data System (ADS)

    Giuffrida, L.; Torrisi, L.; Czarnecka, A.; Wołowski, J.; Quarta, Ge; Calcagnile, L.; Lorusso, A.; Nassisi, V.

    Laser-generated plasma obtained by Ge ablation in vacuum was investigated with the aim to implant energetic Ge ions in light substrates (C, Si, SiO2). Different intensities of laser sources were employed for these experiments: Nd:Yag of Catania-LNS; Nd:Yag of Warsaw-IPPL; excimer laser of Lecce-INFN; iodine laser of Prague-PALS. Different experimental setups were used to generate multiple ion stream emissions, multiple ion energetic distributions, high implantation doses, thin film deposition and post-acceleration effects. `On line' measurements of ion energy were obtained with ion collectors and ion energy analyzer in time-of-flight configuration. `Off line' measurement of Ge implants were obtained with 2.25 MeV helium beam in Rutherford backscattering spectrometry. Results indicated that ion implants show typical deep profiles only for substrates placed along the normal to the target surface at which the ion energy is maximum.

  7. Method and apparatus for plasma source ion implantation

    DOEpatents

    Conrad, J.R.

    1988-08-16

    Ion implantation into surfaces of three-dimensional targets is achieved by forming an ionized plasma about the target within an enclosing chamber and applying a pulse of high voltage between the target and the conductive walls of the chamber. Ions from the plasma are driven into the target object surfaces from all sides simultaneously without the need for manipulation of the target object. Repetitive pulses of high voltage, typically 20 kilovolts or higher, causes the ions to be driven deeply into the target. The plasma may be formed of a neutral gas introduced into the evacuated chamber and ionized therein with ionizing radiation so that a constant source of plasma is provided which surrounds the target object during the implantation process. Significant increases in the surface hardness and wear characteristics of various materials are obtained with ion implantation in this manner. 7 figs.

  8. Method and apparatus for plasma source ion implantation

    DOEpatents

    Conrad, John R.

    1988-01-01

    Ion implantation into surfaces of three-dimensional targets is achieved by forming an ionized plasma about the target within an enclosing chamber and applying a pulse of high voltage between the target and the conductive walls of the chamber. Ions from the plasma are driven into the target object surfaces from all sides simultaneously without the need for manipulation of the target object. Repetitive pulses of high voltage, typically 20 kilovolts or higher, causes the ions to be driven deeply into the target. The plasma may be formed of a neutral gas introduced into the evacuated chamber and ionized therein with ionizing radiation so that a constant source of plasma is provided which surrounds the target object during the implantation process. Significant increases in the surface hardness and wear characteristics of various materials are obtained with ion implantation in this manner.

  9. Modelling of charging effects in plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    En, William; Cheung, Nathan W.

    1995-03-01

    The charging effects of plasma immersion ion implantation on several device structures is simulated. The simulations use an analytical model which couples the interaction of the plasma and IC devices during plasma implantation. The plasma model is implemented within the circuit simulator SPICE, which allows the model to uses all of the IC device models existing within SPICE. The model of the Fowler-Nordheim tunneling current through thin gate oxides of MOS devices is demonstrated, and shown how it can be used to quantify the damage induced. Charging damage is shown to be strongly affected by the device structure.

  10. Extension of Plasma Source Ion Implantation to Ion Beam Enhanced Deposition

    DTIC Science & Technology

    1989-10-05

    22, 90 (1989). Nitriding/ Carburizing , Cincinnati, Ohio, Septem- 51. M. A. Lieberman, "Model of Plasma Immersion Ion ber 16-20, 1989. Implantation...TYPE AND OATES COVERED 1990 Final I Feb 89 - 31 Jul 89 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Extension of Plasma Source Ion Implantation to Ion Beam...UL NSN 7540-01.280-5500 Standard Form 298 (Rev 2-89) *’@Krab OV ANSI St 139-IS t9-0 Extension of Plasma Source Ion Implantation to Ion Beam Enhanced

  11. Integrated high-voltage modulator for plasma immersion ion implantation with an RF plasma

    NASA Astrophysics Data System (ADS)

    Rogozin, A. I.; Astrelin, V. T.; Richter, E.; Möller, W.

    2003-08-01

    The present investigation focuses on further development of the plasma based high-voltage modulator for plasma immersion ion implantation devices. The modulator produces high-voltage pulses using grid controlled extraction of electrons from the plasma, which is used for the ion implantation. The operation features of the modulator in connection with a radio-frequency plasma are described. The device is applied to nitrogen ion implantations of stainless steel. The results indicate considerable hardness improvement, which confirms the practical utility of the high-voltage modulator.

  12. Direct temperature monitoring for semiconductors in plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Tian, Xiubo; Chu, Paul K.

    2000-07-01

    In situ temperature monitoring is extremely important in plasma immersion ion implantation (PIII) of semiconductors. For instance, the silicon wafer must be heated to 600 °C or higher in separation by plasma implantation of oxygen, and in the PIII/ion-cut process, the wafer temperature must remain below 300 °C throughout the experiment. In this article, we present a thermocouple-based direct temperature measurement system for planar samples such as silicon wafers. In order to ensure reliable high-voltage operation and overall electrical isolation, the thermocouple assembly and wires are integrated into the sample chuck and feedthrough. Hydrogen plasma immersion ion implantation is performed in silicon to demonstrate the effectiveness and reliability of the device. Our experimental results indicate that instrumental parameters such as implantation voltage, pulse duration, and pulsing frequency affect the sample temperature to a different extent. The measured temperature rise is higher than that predicted by a theoretical model based on the Child-Langmuir law. The discrepancy is attributed to the finite-sample size and the nonplanar, conformal plasma sheath.

  13. Chromium plating pollution source reduction by plasma source ion implantation

    SciTech Connect

    Chen, A.; Sridharan, K.; Dodd, R.A.; Conrad, J.R.; Qiu, X.; Hamdi, A.H.; Elmoursi, A.A.; Malaczynski, G.W.; Horne, W.G.

    1995-12-31

    There is growing concern over the environmental toxicity and workers` health issues due to the chemical baths and rinse water used in the hard chromium plating process. In this regard the significant hardening response of chromium to nitrogen ion implantation can be environmentally beneficial from the standpoint of decreasing the thickness and the frequency of application of chromium plating. In this paper the results of a study of nitrogen ion implantation of chrome plated test flats using the non-line-of-sight Plasma Source Ion Implantation (PSII) process, are discussed. Surface characterization was performed using Scanning Electron Microscopy (SEM), Auger Electron Spectroscopy (AES), and Electron Spectroscopy for Chemical Analysis (ESCA). The surface properties were evaluated using a microhardness tester, a pin-on-disk wear tester, and a corrosion measurement system. Industrial field testing of nitrogen PSII treated chromium plated parts showed an improvement by a factor of two compared to the unimplanted case.

  14. Surface modification of polymeric materials by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Fu, Ricky K. Y.; Cheung, I. T. L.; Mei, Y. F.; Shek, C. H.; Siu, G. G.; Chu, Paul K.; Yang, W. M.; Leng, Y. X.; Huang, Y. X.; Tian, X. B.; Yang, S. Q.

    2005-08-01

    Polymer surfaces typically have low surface tension and high chemical inertness and so they usually have poor wetting and adhesion properties. The surface properties can be altered by modifying the molecular structure using plasma immersion ion implantation (PIII). In this work, Nylon-6 was treated using oxygen/nitrogen PIII. The observed improvement in the wettability is due to the oxygenated and nitrogen (amine) functional groups created on the polymer surface by the plasma treatment. X-ray photoelectron spectroscopy (XPS) results show that nitrogen and oxygen plasma implantation result in C-C bond breaking to form the imine and amine groups as well as alcohol and/or carbonyl groups on the surface. The water contact angle results reveal that the surface wetting properties depend on the functional groups, which can be adjusted by the ratio of oxygen-nitrogen mixtures.

  15. Sheath overlap during very large scale plasma source ion implantation

    NASA Astrophysics Data System (ADS)

    Cluggish, B. P.; Munson, C. P.

    1998-12-01

    Measurements of plasma source ion implantation have been performed on a large target of complex geometry. The target consists of 1000 aluminum, automotive piston surrogates mounted on four racks; total surface area is over 16 m2. The four racks are positioned parallel to each other, 0.25 m apart, in an 8 m3 vacuum chamber. The racks of pistons are immersed in a capacitive radio frequency plasma, with an argon gas pressure of 20-65 mPa. Langmuir probe measurements indicate that the plasma density profile is highly nonuniform, due to particle losses to the racks of pistons. The plasma ions are implanted into the pistons by pulse biasing the workpiece to negative voltages as low as -18 kV for up to 20 μs. During the voltage pulse, the high-voltage sheaths from adjacent racks of pistons converge towards each other. At plasma densities less than 109 cm-3 the sheaths are observed to overlap. Measurements of the sheath overlap time are compared with standard analytic theory and with simulations run with a two-dimensional particle-in-cell code.

  16. Hardening of Metallic Materials Using Plasma Immersion Ion Implantation (PIII)

    NASA Astrophysics Data System (ADS)

    Xu, Yufan; Clark, Mike; Flanagan, Ken; Milhone, Jason; Nonn, Paul; Forest, Cary

    2016-10-01

    A new approach of Plasma Immersion Ion Implantation (PIII) has been developed with the Plasma Couette Experiment Upgrade (PCX-U). The new approach efficiently reduces the duty cycle under the same average power for PIII. The experiment uses a Nitrogen plasma at a relatively high density of 1010 1011 cm-3 with ion temperatures of < 2 eV and electron temperature of 5 10 eV. The pulser for this PIII experiment has a maximum negative bias greater than 20kV, with 60Hz frequency and a 8 μs on-time in one working cycle. The samples (Alloy Steel 9310) are analyzed by a Vicker Hardness Tester to study the hardness and X-ray Photoelectron Spectroscopy (XPS) to study implantation density and depth. Different magnetic fields are also applied on samples to reduce the energy loss and secondary emission. Higher efficiency of implantation is expected from this experiment and the results will be presented. Hilldale Undergraduate/Faculty Research Fellowship of University of Wisconsin-Madison; Professor Cary Forest's Kellett Mid-Career Faculty Award.

  17. Deep Trench Doping by Plasma Immersion Ion Implantation in Silicon

    SciTech Connect

    Nizou, S.; Vervisch, V.; Etienne, H.; Torregrosa, F.; Roux, L.; Ziti, M.; Alquier, D.; Roy, M.

    2006-11-13

    The realization of three dimensional (3D) device structures remains a great challenge in microelectronics. One of the main technological breakthroughs for such devices is the ability to control dopant implantation along silicon trench sidewalls. Plasma Immersion Ion Implantation (PIII) has shown its wide efficiency for specific doping processing in semiconductor applications. In this work, we propose to study the capability of PIII method for large scale silicon trench doping. Ultra deep trenches with high aspect ratio were etched on 6'' N type Si wafers. Wafers were then implanted with a PIII Pulsion system using BF3 gas source at various pressures and energies. The obtained results evidence that PIII can be used and are of grateful help to define optimized processing conditions to uniformly dope silicon trench sidewalls through the wafers.

  18. Simulation of BF{sub 3} plasma immersion ion implantation into silicon

    SciTech Connect

    Burenkov, A.; Hahn, A.; Spiegel, Y.; Etienne, H.; Torregrosa, Frank

    2012-11-06

    Plasma immersion ion implantation from a BF{sub 3} plasma into crystalline (100) silicon was performed using the PULSION plasma doping tool. Implanted boron profiles were measured with the SIMS method and simulated using models with different levels of sophistication. The physical implantation model is based on an analytical energy distribution for ions from the plasma and uses a Monte-Carlo simulation code. An analytical model of plasma immersion ion implantation that assumes a uniform and isotropic implantation was implemented in a software module called IMP3D. The functionality of this module which was initially envisaged for the three-dimensional simulation of conventional ion implantation was extended to plasma immersion ion implantation and examples of 2D and 3D simulations from this are presented.

  19. Doping concentration evaluation using plasma propagation models in plasma immersion ion implantation (PIII) system

    NASA Astrophysics Data System (ADS)

    Gupta, Dushyant; Prasad, B.; George, P. J.

    2004-01-01

    Plasma immersion ion implantation (PIII) is a high dose-rate implantation process technique in the area of semiconductor device fabrication used to fabricate various device structures like shallow junction, silicon on insulators and in the processing of flat panel display materials, trench doping, etc. The basic mechanism of ions source and their acceleration in PIII technique is different from that of the conventional ion-implantation. In this, the target is immersed in a plasma source and the implantation is done by accelerating the ions with a negative pulse bias voltage, applied to the target. The dynamics of ion transport and the implantation is different from line-of-sight implantation. In this paper, the doping of individual ions (Ar, He and N), in a collisionless PIII system is studied analytically when a negative pulse of 10 kV is applied to the target. The net ion doping concentration in one pulse duration has also been computed during the propagation of plasma sheaths.

  20. Self-consistent circuit model for plasma source ion implantation

    SciTech Connect

    Chung, Kyoung-Jae; Jung, Soon-Wook; Choe, Jae-Myung; Kim, Gon-Ho; Hwang, Y. S.

    2008-02-15

    A self-consistent circuit model which can describe the dynamic behavior of the entire pulsed system for plasma source ion implantation has been developed and verified with experiments. In the circuit model, one-dimensional fluid equations of plasma sheath have been numerically solved with self-consistent boundary conditions from the external circuit model including the pulsed power system. Experiments have been conducted by applying negative, high-voltage pulses up to -10 kV with a capacitor-based pulse modulator to the planar target in contact with low-pressure argon plasma produced by radio-frequency power at 13.56 MHz. The measured pulse voltage and current waveforms as well as the sheath motion have shown good agreements with the simulation results.

  1. Estimation of Nitrogen Ion Energy in Sterilization Technology by Plasma Based Ion Implantation

    NASA Astrophysics Data System (ADS)

    Kondou, Youhei; Nakashima, Takeru; Tanaka, Takeshi; Takagi, Toshinori; Watanabe, Satoshi; Ohkura, Kensaku; Shibahara, Kentaro; Yokoyama, Shin

    Plasma based ion implantation (PBII) with negative voltage pulses to the test specimen has been applied to the sterilization process as a technique suitable for three-dimensional work pieces. Pulsed high negative voltage (5 μs pulse width, 300 pulses/s, -800 V to -15 kV) was applied to the electrode in this process at a gas pressure of 2.4 Pa of N2. We found that the PBII process, in which N2 gas self-ignitted plasma generated by only pulsed voltages is used, reduces the number of active Bacillus pumilus cell. The number of bacteria survivors was reduced by 10-5 x with 5 min exposure. Since the ion energy is the most important processing parameter, a simple method to estimate the nitrogen ion energy from distribution of nitrogen atoms in Si implanted by PBII was developed. The implanted ion energy is discussed from the SIMS in depth profiles.

  2. Surface insulating properties of titanium implanted alumina ceramics by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Zhu, Mingdong; Song, Falun; Li, Fei; Jin, Xiao; Wang, Xiaofeng; Wang, Langping

    2017-09-01

    The insulating property of the alumina ceramic in vacuum under high voltage is mainly limited by its surface properties. Plasma immersion ion implantation (PIII) is an effective method to modify the surface chemical and physical properties of the alumina ceramic. In order to improve the surface flashover voltage of the alumina ceramic in vacuum, titanium ions with an energy of about 20 keV were implanted into the surface of the alumina ceramic using the PIII method. The surface properties of the as-implanted samples, such as the chemical states of the titanium, morphology and surface resistivity, were characterized by X-ray photoelectron spectroscopy, scanning electron microscope and electrometer, respectively. The surface flashover voltages of the as-implanted alumina samples were measured by a vacuum surface flashover experimental system. The XPS spectra revealed that a compound of Ti, TiO2 and Al2O3 was formed in the inner surface of the alumina sample. The electrometer results showed that the surface resistivity of the implanted alumina decreased with increased implantation time. In addition, after the titanium ion implantation, the maximum hold-off voltage of alumina was increased to 38.4 kV, which was 21.5% higher than that of the unimplanted alumina ceramic.

  3. New developments in metal ion implantation by vacuum arc ion sources and metal plasma immersion

    SciTech Connect

    Brown, I.G.; Anders, A.; Anders, S.

    1996-12-31

    Ion implantation by intense beams of metal ions can be accomplished using the dense metal plasma formed in a vacuum arc discharge embodied either in a vacuum arc ion source or in a metal plasma immersion configuration. In the former case high energy metal ion beams are formed and implantation is done in a more-or-less conventional way, and in the latter case the substrate is immersed in the plasma and repetitively pulse-biased so as to accelerate the ions at the high voltage plasma sheath formed at the substrate. A number of advances have been made in the last few years, both in plasma technology and in the surface modification procedures, that enhance the effectiveness and versatility of the methods, including for example: controlled increase of the in charge states produced; operation in a dual metal-gaseous ion species mode; very large area beam formation; macroparticle filtering; and the development of processing regimes for optimizing adhesion, morphology and structure. These complementary ion processing techniques provide the plasma tools for doing ion surface modification over a very wide parameter regime, from pure ion implantation at energies approaching the MeV level, through ion mixing at energies in the {approximately}1 to {approximately}100 keV range, to IBAD-like processing at energies from a few tens of eV to a few keV. Here the authors review the methods, describe a number of recent developments, and outline some of the surface modification applications to which the methods have been put. 54 refs., 9 figs.

  4. Plasma source ion-implantation technique for surface modification of materials

    NASA Astrophysics Data System (ADS)

    Conrad, J. R.; Radtke, J. L.; Dodd, R. A.; Worzala, Frank J.; Tran, Ngoc C.

    1987-12-01

    Plasma source ion-implantation (PSII) is a new ion-implantation technique which has been optimized for surface modification of materials such as metals, plastics, and ceramics. PSII departs radically from conventional implantation technology by circumventing the line-of-sight restriction inherent in conventional ion implantation. In PSII, targets to be implanted are placed directly in a plasma source and then pulse biased to a high negative potential. A plasma sheath forms around the target and ions bombard the entire target simultaneously. Preliminary experiments have demonstrated that PSII: (1) efficiently implants ions to concentrations and depths required for surface modification, (2) produces material with improved microhardness and wear properties, and (3) dramatically improves the life of manufacturing tools in actual industrial applications. For example, the tool life of M-2 pierce punches used to produce holes in mild steel plate has been increased by a factor of 80.

  5. Measurement of Adhesion Strength of DLC Film Prepared by Utilizing Plasma-Based Ion Implantation

    NASA Astrophysics Data System (ADS)

    Oka, Yoshihiro; Yatsuzuka, Mitsuyasu

    High-adhesion diamond-like carbon (DLC) film was prepared by a hybrid process of plasma-based ion implantation and deposition using superimposed RF and high-voltage pulses. The adhesion strength of DLC film on a stainless steel (SUS304) was enhanced by the carbon ion implantation to the substrate. Furthermore, ion implantation of mixed carbon and silicon led to considerable enhancement of adhesion strength above the resin glue strength. The adhesion strength of DLC film on the aluminum alloy (A-5052) was improved above the resin glue strength only by the carbon ion implantation to the substrate.

  6. Platelet adhesion and plasma protein adsorption control of collagen surfaces by He + ion implantation

    NASA Astrophysics Data System (ADS)

    Kurotobi, K.; Suzuki, Y.; Nakajima, H.; Suzuki, H.; Iwaki, M.

    2003-05-01

    He + ion implanted collagen-coated tubes with a fluence of 1 × 10 14 ions/cm 2 were exhibited antithrombogenicity. To investigate the mechanisms of antithrombogenicity of these samples, plasma protein adsorption assay and platelet adhesion experiments were performed. The adsorption of fibrinogen (Fg) and von Willebrand factor (vWf) was minimum on the He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2. Platelet adhesion (using platelet rich plasma) was inhibited on the He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and was accelerated on the untreated collagen and ion implanted collagen with fluences of 1 × 10 13, 1 × 10 15 and 1 × 10 16 ions/cm 2. Platelet activation with washed platelets was observed on untreated collagen and He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and was inhibited with fluences of 1 × 10 13, 1 × 10 15 and 1 × 10 16 ions/cm 2. Generally, platelets can react with a specific ligand inside the collagen (GFOGER sequence). The results of platelets adhesion experiments using washed platelets indicated that there were no ligands such as GFOGER on the He + ion implanted collagen over a fluence of 1 × 10 13 ions/cm 2. On the 1 × 10 14 ions/cm 2 implanted collagen, no platelet activation was observed due to the influence of plasma proteins. From the above, it is concluded that the decrease of adsorbed Fg and vWf caused the antithrombogenicity of He + ion implanted collagen with a fluence of 1 × 10 14 ions/cm 2 and that plasma protein adsorption took an important role repairing the graft surface.

  7. Operations manual for the plasma source ion implantation economics program

    SciTech Connect

    Bibeault, M.L.; Thayer, G.R.

    1995-10-01

    Plasma Source Ion Implantation (PSII) is a surface modification technique for metal. PSIICOSTMODEL95 is an EXCEL-based program that estimates the cost for implementing a PSII system in a manufacturing setting where the number of parts to be processed is over 5,000 parts per day and the shape of each part does not change from day to day. Overall, the manufacturing process must be very well defined and should not change. This document is a self-contained manual for PSIICOSTMODEL95. It assumes the reader has some general knowledge of the technical requirements for PSII. Configuration of the PSII process versus design is used as the methodology in PSIICOSTMODEL95. The reason behind this is twofold. First, the design process cannot be programmed into a computer when the relationships between design variables are not understood. Second, the configuration methodology reduces the number of assumptions that must be programmed into our software. Misuse of results are less likely to occur if the user has fewer assumptions to understand.

  8. Effective implantation of light emitting centers by plasma immersion ion implantation and focused ion beam methods into nanosized diamond

    NASA Astrophysics Data System (ADS)

    Himics, L.; Tóth, S.; Veres, M.; Tóth, A.; Koós, M.

    2015-02-01

    Two different implantation techniques, plasma immersion ion implantation and focused ion beam, were used to introduce nitrogen ions into detonation nanodiamond crystals with the aim to create nitrogen-vacancy related optically active centers of light emission in near UV region. Previously samples were subjected to a defect creation process by helium irradiation in both cases. Heat treatments at different temperatures (750 °C, 450 °C) were applied in order to initiate the formation of nitrogen-vacancy related complex centers and to decrease the sp2 carbon content formed under different treatments. As a result, a relatively narrow and intensive emission band with fine structure at 2.98, 2.83 and 2.71 eV photon energies was observed in the light emission spectrum. It was assigned to the N3 complex defect center. The formation of this defect center can be expected by taking into account the relatively high dose of implanted nitrogen ions and the overlapped depth distribution of vacancies and nitrogen. The calculated depth profiles distribution for both implanted nitrogen and helium by SRIM simulation support this expectation.

  9. Effect of bias voltage on coating homogeneity in plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Slabodchikov, Vladimir A.; Borisov, Dmitry P.; Kuznetsov, Vladimir M.

    2016-11-01

    The paper presents research results demonstrating the influence of bias on the homogeneity of plasma immersion ion implantation. The research results allow the conclusion that plasma immersion ion implantation can be used to advantage for surface modification of medical materials, e.g., nickel-titanium (NiTi) alloys. In particular, doing of NiTi with silicon at pulsed bias provides highly homogeneous surface treatment.

  10. A new method for inner surface modification by plasma source ion implantation (PSII)

    NASA Astrophysics Data System (ADS)

    Liu, Bin; Liu, Chizi; Cheng, Dajung; Zhang, Guling; He, Rui; Yang, Si-Ze

    2001-12-01

    A new method for inner surface modification, named grid-enhanced inner surface modification by plasma source ion implantation (PSII), was proposed and demonstrated in this paper. By introducing an RF plasma core, which is produced between a central cathode and a coaxial grid electrode, and sputtering the cathode, uniform ion implantation and film deposition on the inner surface of a tubular sample can be realized based upon the PSII technique.

  11. High Resolution Rutherford Back Scattering Estimation of the Surface Implanted Nitrogen Ion by Using Plasma-based Ion Implantation

    NASA Astrophysics Data System (ADS)

    Tanaka, Takeshi; Takagi, Toshinori

    Plasma-based ion implantation (PBII) with negative voltage pulses to the test specimen has been applied to the sterilization process as a technique suitable for three-dimensional work pieces. Pulsed high negative voltage (5 μs pulse width, 300 pulses/s, -800 V to -15 kV) was applied to the electrode in this process at a gas pressure of 2.4 Pa of N2. We found that the PBII process, in which (N2 gas self-ignitted plasma generated by only pulsed voltages is used) reduces the numbers of active Bacillus pumilus cell. The number of bacteria survivors was reduced by 10-5 x with 5 min exposure. As the ion energy is one of the important processing parameters on sterilization of the surface, the ion energy is discussed from the high resolution RBS depth profile.

  12. Plasma-based ion implantation sterilization technique and ion energy estimation

    NASA Astrophysics Data System (ADS)

    Tanaka, T.; Watanabe, S.; Shibahara, K.; Yokoyama, S.; Takagi, T.

    2005-07-01

    Plasma-based ion implantation (PBII) is applied as a sterilization technique for three-dimensional work pieces. In the sterilization process, a pulsed negative high voltage (5 μs pulse width, 300 pulses/s,-800 V to -13 kV) is applied to the electrode (workpiece) under N2 at a gas pressure of 2.4 Pa. The resultant self-ignited plasma is shown to successfully reduce the number of active Bacillus pumilus cells by 105 times after 5 min of processing. The nitrogen ion energy is estimated using a simple method based on secondary ion mass spectroscopy analysis of the vertical distribution of nitrogen in PBII-treated Si.

  13. Application of nitrogen plasma immersion ion implantation to titanium nasal implants with nanonetwork surface structure

    SciTech Connect

    Sun, Ying-Sui; Yang, Wei-En; Zhang, Lan; Zhu, Hongqin; Lan, Ming-Ying; Lee, Sheng-Wei; Huang, Her-Hsiung

    2016-07-15

    In nasal reconstruction, the response of cells to titanium (Ti) implants is mainly determined by surface features of the implant. In a pilot study, the authors applied electrochemical anodization to Ti surfaces in an alkaline solution to create a network of nanoscale surface structures. This nanonetwork was intended to enhance the responses of primary human nasal epithelial cell (HNEpC) to the Ti surface. In this study, the authors then treated the anodized, nanonetwork-structured Ti surface using nitrogen plasma immersion ion implantation (NPIII) in order to further improve the HNEpC response to the Ti surface. Subsequently, surface characterization was performed to elucidate morphology, roughness, wettability, and chemistry of specimens. Cytotoxicity, blood, and HNEpC responses were also evaluated. Our results demonstrate that NPIII treatment led to the formation of a noncytotoxic TiN-containing thin film (thickness <100 nm) on the electrochemically anodized Ti surface with a nanonetwork-structure. NPIII treatment was shown to improve blood clotting and the adhesion of platelets to the anodized Ti surface as well as the adhesion and proliferation of hNEpC. This research spreads our understanding of the fact that a TiN-containing thin film, produced using NPIII treatment, could be used to improve blood and HNEpC responses to anodized, nanonetwork-structured Ti surfaces in nasal implant applications.

  14. Ion Implantation of Silver Nanoparticles on Electrodeposited Polycarbazole Via Plasma Sputter Type Negative Ion Sources

    NASA Astrophysics Data System (ADS)

    Marquez, M. C.; Mascarinas, V.; Ramos, H.

    2017-09-01

    The discovery of conducting polymer has brought tremendous advancement in developing various polymeric materials, Carbazole pendants of poly(ethyl methacrylate) was cross-linked via an electrochemical route. The obtained film of poly( carbazole ethyl methacrylate) electrodeposited on the surface of indium tin oxide (ITO) was modified by implanting silver nanoparticles on its surface. This was done using Plasma Sputter-type Negative Ion Sources (PSTNIS) The modified and unmodified films of polycarbazole were characterized to assess its properties. Implanting silver nanoparticles on the surface of the cross-linked polymer abruptly changed its surface roughness, absorbance in the visible region and its current-voltage characteristic. A more pronounced diode-like characteristic was observed with a turn-on voltage of ∼0.4V. Investigation and tailoring the properties of electropolymerized carbazole attached to poly (ethyl methacrylate) backbone with implanted silver nanoparticles could lead to important materials with impact in optoelectronic devices.

  15. Plasma source ion implantation to increase the adhesion of subsequently deposited coatings

    SciTech Connect

    Wood, B.P.; Walter, K.C.; Taylor, T.N.

    1997-10-01

    In Plasma Source Ion Implantation (PSII) an object is placed in a plasma and pulse biased to a high negative potential, so as to implant the plasma ions into the surface of the object. Although ion implantation, by itself, can yield desirable surface modification, it is even more useful as a method of creating a functionally graded interface between the substrate material and a subsequently deposited coating, which may be produced by altering operating conditions on the same plasma source. Although this interfacial region is very thin - as little as 20 nm - it can greatly increase the adhesion of the deposited coatings. We present here a description of this process, and compare a simulation of the graded interface with an XPS depth profile of the interfacial region for erbium metal implanted into steel.

  16. Formation of Wear Resistant Steel Surfaces by Plasma Immersion Ion Implantation

    SciTech Connect

    Maendl, S.; Rauschenbach, B.

    2003-08-26

    Plasma immersion ion implantation (PIII) is a versatile and fast method for implanting energetic ions into large and complex shaped three-dimensional objects where the ions are accelerated by applying negative high voltage pulses to a substrate immersed in a plasma. As the line-of-sight restrictions of conventional implanters are circumvented, it results in a fast and cost-effective technology. Implantation of nitrogen at 30 - 40 keV at moderate temperatures of 200 - 400 deg. C into steel circumvents the diminishing thermal nitrogen activation encountered, e.g., in plasma nitriding in this temperature regime, thus enabling nitriding of additional steel grades. Nitride formation and improvement of the mechanical properties after PIII are presented for several steel grades, including AISI 316Ti (food industry), AISI D2 (used for bending tools) and AISI 1095 (with applications in the textile industry)

  17. Effect of plasma immersion ion implantation in TiNi implants on its interaction with animal subcutaneous tissues

    NASA Astrophysics Data System (ADS)

    Lotkov, Aleksandr I.; Kashin, Oleg A.; Kudryavtseva, Yuliya A.; Shishkova, Darya K.; Krukovskii, Konstantin V.; Kudryashov, Andrey N.

    2016-08-01

    Here we investigated in vivo interaction of Si-modified titanium nickelide (TiNi) samples with adjacent tissues in a rat subcutaneous implant model to assess the impact of the modification on the biocompatibility of the implant. Modification was performed by plasma immersion ion processing, which allows doping of different elements into surface layers of complex-shaped articles. The aim of modification was to reduce the level of toxic Ni ions on the implant surface for increasing biocompatibility. We identified a thin connective tissue capsule, endothelial cells, and capillary-like structures around the Si-modified implants both 30 and 90 days postimplantation. No signs of inflammation were found. In conclusion, modification of TiNi samples with Si ions increases biocompatibility of the implant.

  18. Optical properties of surface modified polypropylene by plasma immersion ion implantation technique

    SciTech Connect

    Ahmed, Sk. Faruque; Moon, Myoung-Woon; Kim, Chansoo; Lee, Kwang-Ryeol; Jang, Yong-Jun; Han, Seonghee; Choi, Jin-Young; Park, Won-Woong

    2010-08-23

    The optical band gap and activation energy of polypropylene (PP) induced by an Ar plasma immersion ion implantation technique were studied in detail. It was revealed that the structural alternation with an increase in polymer chain cross-linking in the ion beam affected layer enhanced the optical properties of PP. The optical band gap, calculated from the transmittance spectra, decreased from 3.44 to 2.85 eV with the Ar plasma ion energy from 10 to 50 keV. The activation energy, determined from the band tail of the transmittance spectra, decreased while the electrical conductivity increased with the Ar plasma ion energy.

  19. Method For Plasma Source Ion Implantation And Deposition For Cylindrical Surfaces

    DOEpatents

    Fetherston, Robert P. , Shamim, Muhammad M. , Conrad, John R.

    1997-12-02

    Uniform ion implantation and deposition onto cylindrical surfaces is achieved by placing a cylindrical electrode in coaxial and conformal relation to the target surface. For implantation and deposition of an inner bore surface the electrode is placed inside the target. For implantation and deposition on an outer cylindrical surface the electrode is placed around the outside of the target. A plasma is generated between the electrode and the target cylindrical surface. Applying a pulse of high voltage to the target causes ions from the plasma to be driven onto the cylindrical target surface. The plasma contained in the space between the target and the electrode is uniform, resulting in a uniform implantation or deposition of the target surface. Since the plasma is largely contained in the space between the target and the electrode, contamination of the vacuum chamber enclosing the target and electrodes by inadvertent ion deposition is reduced. The coaxial alignment of the target and the electrode may be employed for the ion assisted deposition of sputtered metals onto the target, resulting in a uniform coating of the cylindrical target surface by the sputtered material. The independently generated and contained plasmas associated with each cylindrical target/electrode pair allows for effective batch processing of multiple cylindrical targets within a single vacuum chamber, resulting in both uniform implantation or deposition, and reduced contamination of one target by adjacent target/electrode pairs.

  20. Plasma immersion ion implantation for the efficient surface modification of medical materials

    SciTech Connect

    Slabodchikov, Vladimir A. Borisov, Dmitry P. Kuznetsov, Vladimir M.

    2015-10-27

    The paper reports on a new method of plasma immersion ion implantation for the surface modification of medical materials using the example of nickel-titanium (NiTi) alloys much used for manufacturing medical implants. The chemical composition and surface properties of NiTi alloys doped with silicon by conventional ion implantation and by the proposed plasma immersion method are compared. It is shown that the new plasma immersion method is more efficient than conventional ion beam treatment and provides Si implantation into NiTi surface layers through a depth of a hundred nanometers at low bias voltages (400 V) and temperatures (≤150°C) of the substrate. The research results suggest that the chemical composition and surface properties of materials required for medicine, e.g., NiTi alloys, can be successfully attained through modification by the proposed method of plasma immersion ion implantation and by other methods based on the proposed vacuum equipment without using any conventional ion beam treatment.

  1. Plasma immersion ion implantation for surface treatment of complex branched structures

    NASA Astrophysics Data System (ADS)

    Kashin, Oleg A.; Lotkov, Alexander I.; Borisov, Dmitry P.; Slabodchikov, Vladimir A.; Kuznetsov, Vladimir M.; Kudryashov, Andrey N.; Krukovsky, Konstantin V.

    2016-11-01

    The paper presents experimental results demonstrating the capabilities of plasma immersion ion implantation of silicon (Si) for surface treatment of complex branched structures such are self-expanding intravascular nickel-titanium (NiTi) stents. Using NiTi stents of diameter 4 and 8 mm, it is shown that plasma immersion ion implantation can provide rather homogeneous doping of their outer and inner surfaces with Si atoms. Also presented are research data on the processes that determine the thickness, composition, and structure of surface layers subjected to this type of treatment.

  2. Basic Aspects of the Formation and Activation of Boron Junctions Using Plasma Immersion Ion Implantation

    SciTech Connect

    Zschaetzsch, G.; Vandervorst, W.; Hoffmann, T.; Goossens, J.; Everaert, J.-L.; Agua Borniquel, J. I. del; Poon, T.

    2008-11-03

    This study investigates the basic aspects of junction formation using Plasma Immersion Ion Implantation using BF{sub 3} and addresses the role of (pre)amorphization, C(F)-co-implantation, plasma parameters (bias, dose) and the thermal anneal cycle (spike versus msec laser anneal). The basic physics are studied using Secondary Ion Mass Spectrometry, sheet resistance and using four point probe and RsL. Profiles with junction depths ranging from 10-12 nm and sheet resistance values below 800 Ohm/sq are readily achievable.

  3. Microstructure characteristics of steel M50 implanted with nitrogen by plasma-based ion implantation at elevated temperature

    NASA Astrophysics Data System (ADS)

    Xu, Shuyan; Ma, Xinxin; Sun, Mingren; Sun, Yue; Yukimura, Ken

    2006-01-01

    Steel M50 was modified by plasma-based ion implantation (PBII) at different temperatures. The results of scanning electron microscope (SEM) indicate that PBII at elevated temperature can reduce both grain size of substrate and precipitates in the implanted layer and remove the network microstructure of carbides in the substrate. Glancing angle X-ray diffraction (GXRD) analysis indicates that the elevated temperature is in favor of the formation of nitrides. The diffraction peaks of nitrides are obvious when the temperature is higher than 300 °C with implantation voltage of 25 kV.

  4. High power impulse magnetron sputtering and related discharges: scalable plasma sources for plasma-based ion implantation and deposition

    SciTech Connect

    Anders, Andre

    2009-09-01

    High power impulse magnetron sputtering (HIPIMS) and related self-sputtering techniques are reviewed from a viewpoint of plasma-based ion implantation and deposition (PBII&D). HIPIMS combines the classical, scalable sputtering technology with pulsed power, which is an elegant way of ionizing the sputtered atoms. Related approaches, such as sustained self-sputtering, are also considered. The resulting intense flux of ions to the substrate consists of a mixture of metal and gas ions when using a process gas, or of metal ions only when using `gasless? or pure self-sputtering. In many respects, processing with HIPIMS plasmas is similar to processing with filtered cathodic arc plasmas, though the former is easier to scale to large areas. Both ion implantation and etching (high bias voltage, without deposition) and thin film deposition (low bias, or bias of low duty cycle) have been demonstrated.

  5. Balancing incident heat and ion flow for process optimization in plasma based ion implantation

    NASA Astrophysics Data System (ADS)

    Mändl, S.; Manova, D.; Rauschenbach, B.

    2002-06-01

    Plasma based ion implantation at elevated temperatures is a technology often used to obtain thick surface layers of several µm by thermally activated diffusion, e.g. nitrogen in steel, titanium or aluminium. By lowering the pulse voltage at constant temperature, the current density can be increased at a constant heat flow. However, an upper limit is given by the ratio of the diffusion rate transporting the implanted ions from the surface towards the bulk and the sputter yield. This sputtering of the surface dominates for very high current densities and limits the maximum achievable layer thickness. Different maximum current densities were found for the four investigated systems - nitrogen in different steel grades, aluminium and titanium, as well as oxygen in titanium - reflecting the varying diffusivities. Additional requirements, besides the maximum current density, as a conformal treatment for complex objects containing small holes or trenches, as well as short heating times, can be solved most effectively by pulsed voltages in the range of 2-5 kV and an additional heating of the sample. The problem of a sample cooling time of several hours after the treatment is recognized. A partial solution would be to increase the gas pressure during the cooling phase for a more effective heat dissipation.

  6. Metal plasma immersion ion implantation and deposition (MePIIID) on screw-shaped titanium implant: The effects of ion source, ion dose and acceleration voltage on surface chemistry and morphology.

    PubMed

    Kang, Byung-Soo; Sul, Young-Taeg; Jeong, Yongsoo; Byon, Eungsun; Kim, Jong-Kuk; Cho, Suyeon; Oh, Se-Jung; Albrektsson, Tomas

    2011-07-01

    The present study investigated the effect of metal plasma immersion ion implantation and deposition (MePIIID) process parameters, i.e., plasma sources of magnesium and calcium, ion dose, and acceleration voltage on the surface chemistry and morphology of screw-type titanium implants that have been most widely used for osseointegrated implants. It is found that irrespective of plasma ion source, surface topography and roughness showed no differences at the nanometer level; that atom concentrations increased with ion dose but decreased with acceleration voltage. Data obtained from X-ray photoelectron spectroscopy and auger electron spectroscopy suggested that MePIIID process produces 'intermixed' layer of cathodic arc deposition and plasma immersion ion implantation. The MePIIID process may create desired bioactive surface chemistry of dental and orthopaedic implants by tailoring ion and plasma sources and thus enable investigations of the effect of the surface chemistry on bone response.

  7. PMOS integrated circuit fabrication using BF3 plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Pico, Carey A.; Lieberman, Michael A.; Cheung, Nathan W.

    1992-01-01

    The feasibility of plasma immersion ion implantation (PHI) for multi-implant integrated circuit fabrication is demonstrated. Patterned Si wafers were immersed in a BF3 plasma for p-type doping steps. Boron implants of up to 3 × 1015 atoms/cm2 were achieved by applying microsecond negative voltage (-2 to -30 kV) pulses to the wafers at a frequency of 100 Hz to 1 kHz. After implantation the wafers were annealed using rapid thermal annealing (RTA) at 1060° C for 20 sec to activate the dopants and to recrystallize the implant damaged Si. For the PMOS process sequence both the Si source-drain and polycrystalline Si (poly-Si) gate doping steps were performed using PIII. The functionality of several types of devices, including diodes, capacitors, and transistors, were electrically measured to evaluate the compatibility of PIII with MOS process integration.

  8. Carbon plasma immersion ion implantation of nickel-titanium shape memory alloys.

    PubMed

    Poon, R W Y; Yeung, K W K; Liu, X Y; Chu, P K; Chung, C Y; Lu, W W; Cheung, K M C; Chan, D

    2005-05-01

    Nickel-titanium (NiTi) shape memory alloys possess super-elasticity in addition to the well-known shape memory effect and are potentially suitable for orthopedic implants. However, a critical concern is the release of harmful Ni ions from the implants into the living tissues. We propose to enhance the corrosion resistance and other surface and biological properties of NiTi using carbon plasma immersion ion implantation and deposition (PIII&D). Our corrosion and simulated body fluid tests indicate that either an ion-mixed amorphous carbon coating fabricated by PIII&D or direct carbon PIII can drastically improve the corrosion resistance and block the out-diffusion of Ni from the materials. Our tribological tests show that the treated surfaces are mechanically more superior and cytotoxicity tests reveal that both sets of plasma-treated samples favor adhesion and proliferation of osteoblasts.

  9. Radial 32P ion implantation using a coaxial plasma reactor: Activity imaging and numerical integration

    NASA Astrophysics Data System (ADS)

    Fortin, M. A.; Dufresne, V.; Paynter, R.; Sarkissian, A.; Stansfield, B.

    2004-12-01

    Beta-emitting biomedical implants are currently employed in angioplasty, in the treatment of certain types of cancers, and in the embolization of aneurysms with platinum coils. Radioisotopes such as 32P can be implanted using plasma-based ion implantation (PBII). In this article, we describe a reactor that was developed to implant radioisotopes into cylindrical metallic objects. The plasma first ionizes radioisotopes sputtered from a target, and then acts as the source of particles to be implanted into the biased biomedical device. The plasma therefore plays a major role in the ionization/implantation process. Following a sequence of implantation tests, the liners protecting the interior walls of the reactor were changed and the radioactivity on them measured. This study demonstrates that the radioactive deposits on these protective liners, adequately imaged by radiography, can indicate the distribution of the radioisotopes that are not implanted. The resulting maps give unique information about the activity distribution, which is influenced by the sputtering of the 32P-containing fragments, their ionization in the plasma, and also by the subsequent ion transport mechanisms. Such information can be interpreted and used to significantly improve the efficiency of the implantation procedure. Using a surface barrier detector, a comparative study established a relationship between the gray scale of radiographs of the liners, and activity measurements. An integration process allows the quantification of the activities on the walls and components of the reactor. Finally, the resulting integral of the 32P activity is correlated to the sum of the radioactivity amounts that were sputtered from radioactive targets inside the implanter before the dismantling procedure. This balance addresses the issue of security regarding PBII technology and confirms the confinement of the radioactivity inside the chamber.

  10. Radial {sup 32}P ion implantation using a coaxial plasma reactor: Activity imaging and numerical integration

    SciTech Connect

    Fortin, M.A.; Dufresne, V.; Paynter, R.; Sarkissian, A.; Stansfield, B.

    2004-12-01

    Beta-emitting biomedical implants are currently employed in angioplasty, in the treatment of certain types of cancers, and in the embolization of aneurysms with platinum coils. Radioisotopes such as {sup 32}P can be implanted using plasma-based ion implantation (PBII). In this article, we describe a reactor that was developed to implant radioisotopes into cylindrical metallic objects. The plasma first ionizes radioisotopes sputtered from a target, and then acts as the source of particles to be implanted into the biased biomedical device. The plasma therefore plays a major role in the ionization/implantation process. Following a sequence of implantation tests, the liners protecting the interior walls of the reactor were changed and the radioactivity on them measured. This study demonstrates that the radioactive deposits on these protective liners, adequately imaged by radiography, can indicate the distribution of the radioisotopes that are not implanted. The resulting maps give unique information about the activity distribution, which is influenced by the sputtering of the {sup 32}P-containing fragments, their ionization in the plasma, and also by the subsequent ion transport mechanisms. Such information can be interpreted and used to significantly improve the efficiency of the implantation procedure. Using a surface barrier detector, a comparative study established a relationship between the gray scale of radiographs of the liners, and activity measurements. An integration process allows the quantification of the activities on the walls and components of the reactor. Finally, the resulting integral of the {sup 32}P activity is correlated to the sum of the radioactivity amounts that were sputtered from radioactive targets inside the implanter before the dismantling procedure. This balance addresses the issue of security regarding PBII technology and confirms the confinement of the radioactivity inside the chamber.

  11. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Implantation of high-energy ions produced by femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Volkov, Roman V.; Golishnikov, D. M.; Gordienko, Vyacheslav M.; Savel'ev, Andrei B.; Chernysh, V. S.

    2005-01-01

    Germanium ions of an expanding plasma were implanted in a silicon collector. The plasma was produced by a femtosecond laser pulse with an intensity of ~1015 W cm-2 at the surface of the solid-state target. A technique was proposed for determining the energy characteristics of the ion component of the laser plasma from the density profile of the ions implanted in the substrate.

  12. Etching and structure transformations in uncured epoxy resin under rf-plasma and plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Kondyurin, Alexey; Bilek, Marcela

    2010-05-01

    Uncured epoxy resin was spun onto silicon wafer and treated by plasma and plasma immersion ion implantation (PIII) by argon ions with energy up to 20 keV. Ellipsometry, FTIR spectroscopy and optical microscopy methods were used for analysis. The etching, carbonization, oxidation and crosslinking effects were observed. The curing reactions in modified epoxy resin are observed without a hardening agent. A model of structural transformations in epoxy resin under plasma and ion beam irradiation is proposed and discussed in relation to processes in a space environment.

  13. Fabrication of Genesis Sample Simulants Using Plasma Source Ion Implantation (PSII)

    NASA Technical Reports Server (NTRS)

    Kuhlman, K. R.

    2002-01-01

    Plasma source ion implantation can be used to fabricate simulant samples for the Genesis mission. These simulants will be needed by investigators to validate sample preparation and analysis techniques for the returned Genesis samples. Additional information is contained in the original extended abstract.

  14. Fabrication of Genesis Sample Simulants Using Plasma Source Ion Implantation (PSII)

    NASA Technical Reports Server (NTRS)

    Kuhlman, K. R.

    2002-01-01

    Plasma source ion implantation can be used to fabricate simulant samples for the Genesis mission. These simulants will be needed by investigators to validate sample preparation and analysis techniques for the returned Genesis samples. Additional information is contained in the original extended abstract.

  15. From plasma immersion ion implantation to deposition: A historical perspective on principles and trends

    SciTech Connect

    Anders, Andre

    2001-06-14

    Plasma immersion techniques of surface modification are known under a myriad of names. The family of techniques reaches from pure plasma ion implantation, to ion implantation and deposition hybrid modes, to modes that are essentially plasma film deposition with substrate bias. In the most general sense, all plasma immersion techniques have in common that the surface of a substrate (target) is exposed to plasma and that relatively high substrate bias is applied. The bias is usually pulsed. In this review, the roots of immersion techniques are explored, some going back to the 1800s, followed by a discussion of the groundbreaking works of Adler and Conrad in the 1980s. In the 1990s, plasma immersion techniques matured in theoretical understanding, scaling, and the range of applications. First commercial facilities are now operational. Various immersion concepts are compiled and explained in this review. While gas (often nitrogen) ion implantation dominated the early years, film-forming immersion techniques and semiconductor processing gained importance. In the 1980s and 1990s we have seen exponential growth of the field but signs of slowdown are clear since 1998. Nevertheless, plasma immersion techniques have found, and will continue to have, an important place among surface modification techniques.

  16. Plasma-based fluorine ion implantation into dental materials for inhibition of bacterial adhesion.

    PubMed

    Nurhaerani; Arita, Kenji; Shinonaga, Yukari; Nishino, Mizuho

    2006-12-01

    The aims of this study were to evaluate the fluorine depth profiles of pure titanium (Ti), stainless steel (SUS), and polymethyl methacrylate (PMMA) modified by plasma-based fluorine ion implantation and the effects of fluorine ion implantation on contact angle, fluoride ion release, and S. mutans adhesion. Fluorine-based gases used were Ar+F2 and CF4. By means of SIMS, it was found that the peak count of PMMA was the lowest while that of Ti was the highest. Then, up to one minute after Ar sputtering, the presence of fluorine and chromic fluoride could be detected by XPS in the surface and subsurface layer. As for the effects of using CF4 gas for fluorine ion implantation into SUS substrate, the results were: contact angle was significantly increased; no fluoride ion release was detected; antibacterial activity was significantly increased while initial adhesion was decreased. These findings thus indicated that plasma-based fluorine ion implantation into SUS with CF4 gas provided surface antibacterial activity which was useful in inhibiting bacterial adhesion.

  17. Electron backscatter diffraction characterization of plasma immersion ion implantation effects in stainless steel

    NASA Astrophysics Data System (ADS)

    Davis, Joel; Short, Ken; Wuhrer, Richard; Phillips, Matthew R.; Lumpkin, Gregory R.; Whittle, Karl R.

    2013-01-01

    In these experiments plasma immersion ion implantation is utilised to simulate some of the radiation effects in a nuclear reactor environment. Scanning electron microscopy using the angular selective backscatter detector has revealed observable changes in crystallographic contrast after irradiation with helium ions. Further studies using electron backscatter diffraction in both plan and cross section view allow us to visualize the extent and depth of damage and observe differences in the behavior of different crystalline phases present in several grades of stainless steel.

  18. Nitrogen mass transfer models for plasma-based low-energy ion implantation

    SciTech Connect

    Zheng, Bocong; Wang, Kesheng; Zhang, Zhipeng; Che, Honglong; Lei, Mingkai

    2015-03-15

    The nitrogen mass transfer process in plasma-based low-energy ion implantation (PBLEII) is theoretically and experimentally studied in order to explore the process mechanism of PBLEII and therefore to optimize the apparatus design and the process conditions. An electron cyclotron resonance (ECR) microwave discharge generates the nitrogen plasma with a high density of 10{sup 11}–10{sup 12} ions/cm{sup 3}, which diffuses downstream to the process chamber along the divergent magnetic field. The nitrogen ions in the plasma implant into the surface and transport to the matrix of an austenitic stainless steel under the low negative pulsed bias of −2 kV at a process temperature of 400 °C. A global plasma model is used to simulate the ECR microwave plasma discharge for a range of working pressures and microwave powers. The fluid models are adopted to calculate the plasma downstream diffusion, the sheath expansion and the low-energy ion implantation on the surface. A nonlinear kinetic discrete model is established to describe the nitrogen transport in the austenitic stainless steel and the results are compared with the experimental measurements. Under an average implantation current density of 0.3–0.6 mA/cm{sup 2}, the surface nitrogen concentration in the range from 18.5 to 29 at. % is a critical factor for the nitrogen transport in the AISI 304 austenitic stainless steel by PBLEII, which accelerates the implanted nitrogen diffusion inward up to 6–12 μm during a nitriding time of 4 h.

  19. Surface modification of polymeric substrates by plasma-based ion implantation

    NASA Astrophysics Data System (ADS)

    Okuji, S.; Sekiya, M.; Nakabayashi, M.; Endo, H.; Sakudo, N.; Nagai, K.

    2006-01-01

    Plasma-based ion implantation (PBII) as a tool for polymer modification is studied. Polymeric films have good performances for flexible use, such as food packaging or electronic devices. Compared with inorganic rigid materials, polymers generally have large permeability for gases and moisture, which causes packaged contents and devices to degrade. In order to add a barrier function, surface of polymeric films are modified by PBII. One of the advantageous features of this method over deposition is that the modified surface does not have peeling problem. Besides, micro-cracks due to mechanical stress in the modified layer can be decreased. From the standpoint of mass production, conventional ion implantation that needs low-pressure environment of less than 10-3 Pa is not suitable for continuous large-area processing, while PBII works at rather higher pressure of several Pa. In terms of issues mentioned above, PBII is one of the most expected techniques for modification on flexible substrates. However, the mechanism how the barrier function appears by ion implantation is not well explained so far. In this study, various kinds of polymeric films, including polyethyleneterephthalate (PET), are modified by PBII and their barrier characteristics that depend on the ion dose are evaluated. In order to investigate correlations of the barrier function with implanted ions, modified surface is analyzed with X-ray photoelectron spectroscopy (XPS). It is assumed that the diffusion and sorption coefficients are changed by ion implantation, resulting in higher barrier function.

  20. Application of laser driven fast high density plasma blocks for ion implantation

    NASA Astrophysics Data System (ADS)

    Sari, Amir H.; Osman, F.; Doolan, K. R.; Ghoranneviss, M.; Hora, H.; Höpfl, R.; Benstetter, G.; Hantehzadeh, M. H.

    2005-10-01

    The measurement of very narrow high density plasma blocks of high ion energy from targets irradiated with ps-TW laser pulses based on a new skin depth interaction process is an ideal tool for application of ion implantation in materials, especially of silicon, GaAs, or conducting polymers, for micro-electronics as well as for low cost solar cells. A further application is for ion sources in accelerators with most specifications of many orders of magnitudes advances against classical ion sources. We report on near band gap generation of defects by implantation of ions as measured by optical absorption spectra. A further connection is given for studying the particle beam transforming of n-type semiconductors into p-type and vice versa as known from sub-threshold particle beams. The advantage consists in the use of avoiding aggressive or rare chemical materials when using the beam techniques for industrial applications.

  1. Plasma-based ion implantation and deposition: A review of physics,technology, and applications

    SciTech Connect

    Pelletier, Jacques; Anders, Andre

    2005-05-16

    After pioneering work in the 1980s, plasma-based ion implantation (PBII) and plasma-based ion implantation and deposition (PBIID) can now be considered mature technologies for surface modification and thin film deposition. This review starts by looking at the historical development and recalling the basic ideas of PBII. Advantages and disadvantages are compared to conventional ion beam implantation and physical vapor deposition for PBII and PBIID, respectively, followed by a summary of the physics of sheath dynamics, plasma and pulse specifications, plasma diagnostics, and process modeling. The review moves on to technology considerations for plasma sources and process reactors. PBII surface modification and PBIID coatings are applied in a wide range of situations. They include the by-now traditional tribological applications of reducing wear and corrosion through the formation of hard, tough, smooth, low-friction and chemically inert phases and coatings, e.g. for engine components. PBII has become viable for the formation of shallow junctions and other applications in microelectronics. More recently, the rapidly growing field of biomaterial synthesis makes used of PBII&D to produce surgical implants, bio- and blood-compatible surfaces and coatings, etc. With limitations, also non-conducting materials such as plastic sheets can be treated. The major interest in PBII processing originates from its flexibility in ion energy (from a few eV up to about 100 keV), and the capability to efficiently treat, or deposit on, large areas, and (within limits) to process non-flat, three-dimensional workpieces, including forming and modifying metastable phases and nanostructures. We use the acronym PBII&D when referring to both implantation and deposition, while PBIID implies that deposition is part of the process.

  2. Low flux and low energy helium ion implantation into tungsten using a dedicated plasma source

    NASA Astrophysics Data System (ADS)

    Pentecoste, Lucile; Thomann, Anne-Lise; Melhem, Amer; Caillard, Amael; Cuynet, Stéphane; Lecas, Thomas; Brault, Pascal; Desgardin, Pierre; Barthe, Marie-France

    2016-09-01

    The aim of this work is to investigate the first stages of defect formation in tungsten (W) due to the accumulation of helium (He) atoms inside the crystal lattice. To reach the required implantation conditions, i.e. low He ion fluxes (1011-1014 ions.cm2.s-1) and kinetic energies below the W atom displacement threshold (about 500 eV for He+), an ICP source has been designed and connected to a diffusion chamber. Implantation conditions have been characterized by means of complementary diagnostics modified for measurements in this very low density helium plasma. It was shown that lowest ion fluxes could only be reached for the discharge working in capacitive mode either in α or γ regime. Special attention was paid to control the energy gained by the ions by acceleration through the sheath at the direct current biased substrate. At very low helium pressure, in α regime, a broad ion energy distribution function was evidenced, whereas a peak centered on the potential difference between the plasma and the biased substrate was found at higher pressures in the γ mode. Polycrystalline tungsten samples were exposed to the helium plasma in both regimes of the discharge and characterized by positron annihilation spectroscopy in order to detect the formed vacancy defects. It was found that W vacancies are able to be formed just by helium accumulation and that the same final implanted state is reached, whatever the operating mode of the capacitive discharge.

  3. Plasma Immersion Ion Implantation applied to P+N junction solar cells

    SciTech Connect

    Vervisch, Vanessa; Barakel, D.; Ottaviani, L.; Pasquinelli, M.; Torregrosa, F.

    2006-11-13

    Plasma immersion ion implantation is an alternative doping technique for the formation of Ultra Shallow Junctions in semiconductor. In this study, we present the PIII technology developed by the company Ion Beam Services and called PULSION registered . We explain the advantages of PIII for the conception of thin emitter solar cells and the use of N type silicon in the fabrication of photodiode. Electrical characterisations of solar cells prepared by immersion of silicon wafer in BF3 plasma are presented, showing a satisfying photovoltaic behaviour and more specially an increase of internal quantum efficiency in the short wavelength range, due to the thickness of the emitter.

  4. Simple fabrication of back contact heterojunction solar cells by plasma ion implantation

    NASA Astrophysics Data System (ADS)

    Koyama, Koichi; Yamaguchi, Noboru; Hironiwa, Daisuke; Suzuki, Hideo; Ohdaira, Keisuke; Matsumura, Hideki

    2017-08-01

    A back-contact amorphous-silicon (a-Si)/crystalline silicon (c-Si) heterojunction is one of the most promising structures for high-efficiency solar cells. However, the patterning of back-contact electrodes causes the increase in fabrication cost. Thus, to simplify the fabrication of back-contact cells, we attempted to form p-a-Si/i-a-Si/c-Si and n-a-Si/i-a-Si/c-Si regions by the conversion of a patterned area of p-a-Si/i-a-Si/c-Si to n-a-Si/i-a-Si/c-Si by plasma ion implantation. It is revealed that the conversion of the conduction type can be realized by the plasma ion implantation of phosphorus (P) atoms into p-a-Si/i-a-Si/c-Si regions, and also that the quality of passivation can be kept sufficiently high, the same as that before ion implantation, when the samples are annealed at around 250 °C and also when the energy and dose of ion implantation are appropriately chosen for fitting to a-Si layer thickness and bulk c-Si carrier density.

  5. Plasma immersion ion implantation for sub-22 nm node devices: FD-SOI and Tri-Gate

    SciTech Connect

    Duchaine, J.; Milesi, F.; Coquand, R.; Barraud, S.; Reboh, S.; Gonzatti, F.; Mazen, F.; Torregrosa, Frank

    2012-11-06

    Here, we present and discuss the electrical characteristics of fully depleted MOSFET transistors of planar and tridimensional architecture, doped by Plasma Immersion Ion Implantation (PIII) or Beam Line Ion Implantation (BLII). Both techniques delivered similar and satisfactory results in considering the planar architecture. For tri-dimensional Tri-Gate transistors, the results obtained with PIII are superior.

  6. Corrosion and wear-corrosion behavior of NiTi modified by plasma source ion implantation.

    PubMed

    Tan, L; Dodd, R A; Crone, W C

    2003-10-01

    The understanding of corrosion behavior in NiTi is critical for the devices using this shape-memory alloy. In order to improve the surface properties of NiTi such as corrosion resistance, plasma source ion implantation (PSII) technique was employed with oxygen as incident ions at three levels of implantation dose (5x10(16), 1x10(17) and 3x10(17) ions/cm(-2)). Pitting corrosion and wear-corrosion behavior of control and PSII-modified Ti-50.7at% Ni alloy were evaluated by cyclic potentiodynamic polarization and wear-corrosion measurements. Surface characterization was used to interpret the different corrosion behavior observed between control and oxygen-implanted samples. Results showed that corrosion behavior was influenced by both heat treatment and surface modification. The best pitting corrosion resistance was observed for samples with Af=21 degrees C modified by oxygen implantation at a dose of 1x10(17) ions/cm(-2). Better wear-corrosion resistance was observed for oxygen-implanted samples.

  7. Surface morphology of RF plasma immersion H+ ion implanted and oxidized Si(100) surface

    NASA Astrophysics Data System (ADS)

    Anastasescu, M.; Stoica, M.; Gartner, M.; Bakalova, S.; Szekeres, A.; Alexandrova, S.

    2014-05-01

    The surface morphology of p-Si(100) wafers after RF plasma immersion (PII) H+ ion implantation into a shallow Si surface layer and after subsequent thermal oxidation was studied by atomic-force microscopic (AFM) imaging. After PII implantation of hydrogen ions with an energy of 2 keV and fluences ranging from 1013 cm-2 to 1015 cm-2 the Si wafers were oxidized in dry O2 at temperatures ranging from 700 °C to 800 °C. From the analysis of the AFM images, the surface amplitude parameters were evaluated and considered in terms of the technological conditions. The amplitude parameters showed a clear dependence on the H+ dose and the oxidation temperature, with the tendency of increasing with the increase of both the H+ ion fluence and the oxidation temperature. The implantation causes surface roughening, changing the RMS roughness value from 0.15 nm (typical for a polished Si(100) surface) to the highest value 0.6 nm for the H+ fluence of 1015 ions/cm2. Oxidation of the H+ implanted Si region, as the oxide is growing inward into Si, levels away the pits created by implants and results in a smoother surface, although keeping the RMS values larger than 0.2 nm.

  8. Ion temperature and gas pressure effects on the magnetized sheath dynamics during plasma immersion ion implantation

    SciTech Connect

    Khoram, M.; Ghomi, H. Navab Safa, N.

    2016-03-15

    Here, a collisional magnetized plasma with finite ion temperature is considered to examine the effects of the ion temperature and gas pressure on the plasma-sheath dynamics. We use the two-fluid model of plasma-sheath where the nonlinear equations of a dynamic sheath are solved using a full implicit scheme of finite difference method along with some convenient initial and boundary conditions at the plasma center and target. It is found that the ion temperature only has a significant effect on the characteristics of low voltage sheath, while the gas pressure (collision rate) seriously affects the dynamic characteristics of the low and high voltage plasma-sheath. One can see, increasing the ion temperature in low voltage plasma-sheath causes to increase the temporal curve of the ion dose and the ion impact energy on the target, reduces the temporal curve of the sheath width, and has no any effect on the temporal curve of the ion incident angle on the target. However, rising the gas pressure in low and high voltage plasma-sheath reduces all of these temporal curves.

  9. Corrosion resistance and microstructure of nitrogen plasma source ion implanted bearing steel

    SciTech Connect

    Mente, K.; Baum, C.; Wang, W.; Zhang, L.; Booske, J.; Shohet, J.L.; Jacobs, J.; Freeman, D.; Perez-Albuerne, E.A.

    1996-12-31

    Feasibility of plasma source ion implantation (PSII) treatments for metal corrosion protection of bearing steel in humid environments has been investigated, following successful results with aluminum alloy. The bearing steel coupons have been treated by nitrogen PSII with a statistically designed range of processing conditions, including stage bias implant voltage, and dose. Corrosion properties of the implanted samples were tested using aerated distilled water (72, 168, and 720 hours), 90 F, 90% RH air (24, 120, 816, and 1,464 hours), and a nitric acid soak. The results are compared favorably with 400 C stainless steel, and 52100 steel with nitrogen and argon recoil-implanted chromium. Evidence is seen for an optimal process contour (low voltage-high dose; high voltage-low dose). Results from microstructure analysis will also be presented.

  10. Performance Enhancement of PFET Planar Devices by Plasma Immersion Ion Implantation (P3I)

    SciTech Connect

    Ortolland, Claude; Horiguchi, Naoto; Kerner, Christoph; Chiarella, Thomas; Eyben, Pierre; Everaert, Jean-Luc; Hoffmann, Thomas; Del Agua Borniquel, Jose Ignacio; Poon, Tze; Santhanam, Kartik; Porshnev, Peter; Foad, Majeed; Schreutelkamp, Robert; Absil, Philippe; Vandervorst, Wilfried; Felch, Susan

    2008-11-03

    A study of doping the pMOS Lightly Doped Drain (LDD) by Plasma Immersion Ion Implantation (P3i) with BF3 is presented which demonstrates a better transistor performance compared to standard beam line Ion Implantation (I/I). The benefit of P3i comes from the broad angular distribution of the impinging ions thereby doping the poly-silicon gate sidewall as well. Gate capacitance of short channel devices has been measured and clearly shows this improvement. This model is clearly supported by high resolution 2D-carrier profiles using Scanning Spreading Resistance Microscopy (SSRM) which shows this gate sidewall doping. The broad angular distribution also implies a smaller directional sensitivity (to for instance the detailed gate edge shape) and leads to devices which are perfectly balanced, when Source and Drain electrode are switched.

  11. Broad beam ion implanter

    DOEpatents

    Leung, K.N.

    1996-10-08

    An ion implantation device for creating a large diameter, homogeneous, ion beam is described, as well as a method for creating same, wherein the device is characterized by extraction of a diverging ion beam and its conversion by ion beam optics to an essentially parallel ion beam. The device comprises a plasma or ion source, an anode and exit aperture, an extraction electrode, a divergence-limiting electrode and an acceleration electrode, as well as the means for connecting a voltage supply to the electrodes. 6 figs.

  12. Broad beam ion implanter

    DOEpatents

    Leung, Ka-Ngo

    1996-01-01

    An ion implantation device for creating a large diameter, homogeneous, ion beam is described, as well as a method for creating same, wherein the device is characterized by extraction of a diverging ion beam and its conversion by ion beam optics to an essentially parallel ion beam. The device comprises a plasma or ion source, an anode and exit aperture, an extraction electrode, a divergence-limiting electrode and an acceleration electrode, as well as the means for connecting a voltage supply to the electrodes.

  13. Experiments on plasma immersion ion implantation inside conducting tubes embedded in an external magnetic field

    NASA Astrophysics Data System (ADS)

    Pillaca, E. J. D. M.; Ueda, M.; Reuther, H.; Pichon, L.; Lepienski, C. M.

    2015-12-01

    Tubes of stainless steel (SS) embedded in external magnetic field were used to study the effects of plasma immersion ion implantation (PIII) as a function of their diameter. The study was complemented with and without a grounded auxiliary electrode (AE) placed at the axis of the tube. During the discharge tests in tubes of larger diameter (D = 11 cm), with and without AE, nitrogen gas breakdown was established inside the tube at pressures near 2.0 × 10-2 mbar. Under the same operation conditions, stable plasmas with similar PIII current densities were obtained for both arrangements. Reducing the diameter of the tube (D = 1.5 cm) turned the plasma unstable and made it inappropriate for ion implantation. This situation was solved by supplying gas at higher pressure or using higher magnetic field, without the presence of an AE. Under these conditions, nitrogen PIII treatments of these small diameter tubes were performed but gave not the best implantation results yet. Our results have also shown higher ion implantation current density (16 mA/cm2) in tube of intermediate diameter (D = 4 cm) using AE, compared to largest diameter tube used. In this case, a thick nitrogen layer of about 9 μm was obtained in the SS sample placed inside the tube. As a consequence of this, its structural and mechanical properties were enhanced. These results are attributed to the thermal diffusion promoted by ions hitting the inner wall in a large number due to the presence of the AE and the magnetic field.

  14. Effects Of Ion Energy On Nitrogen Plasma Immersion Ion Implantation In UHMWPE Polymer Through A Metal Grid

    SciTech Connect

    Ueda, M.; Oliveira, R. M.; Rossi, J. O.; Lepienski, C. M.; Vilela, W. A.

    2006-11-13

    Herein, we consider the potential application of plasma immersion ion implantation (PIII) for treatment of polymer surfaces. This paper presents some experimental data for ultra-high molecular weight polyethylene (UHMWPE) implanted with nitrogen using PIII process. This polymer is widely used in medical prosthesis and PIII treatment has revealed to be an ease and cheap way to improve the lifetime of prosthesis made with UHMWPE. Here we show the latest results for UHMWPE surface treatment obtained with the use of a high voltage pulser of 100kV/200A based on coaxial Blumlein technology.

  15. Effects Of Ion Energy On Nitrogen Plasma Immersion Ion Implantation In UHMWPE Polymer Through A Metal Grid

    NASA Astrophysics Data System (ADS)

    Ueda, M.; Oliveira, R. M.; Rossi, J. O.; Lepienski, C. M.; Vilela, W. A.

    2006-11-01

    Herein, we consider the potential application of plasma immersion ion implantation (PIII) for treatment of polymer surfaces. This paper presents some experimental data for ultra-high molecular weight polyethylene (UHMWPE) implanted with nitrogen using PIII process. This polymer is widely used in medical prosthesis and PIII treatment has revealed to be an ease and cheap way to improve the lifetime of prosthesis made with UHMWPE. Here we show the latest results for UHMWPE surface treatment obtained with the use of a high voltage pulser of 100kV/200A based on coaxial Blumlein technology.

  16. Plasma immersion ion implantation of boron for ribbon silicon solar cells

    NASA Astrophysics Data System (ADS)

    Derbouz, K.; Michel, T.; De Moro, F.; Spiegel, Y.; Torregrosa, F.; Belouet, C.; Slaoui, A.

    2013-09-01

    In this work, we report for the first time on the solar cell fabrication on n-type silicon RST (for Ribbon on Sacrificial Template) using plasma immersion ion implantation. The experiments were also carried out on FZ silicon as a reference. Boron was implanted at energies from 10 to 15 kV and doses from 1015 to 1016 cm-2, then activated by a thermal annealing in a conventional furnace at 900 and 950 °C for 30 min. The n+ region acting as a back surface field was achieved by phosphorus spin-coating. The frontside boron emitter was passivated either by applying a 10 nm deposited SiOX plasma-enhanced chemical vapor deposition (PECVD) or with a 10 nm grown thermal oxide. The anti-reflection coating layer formed a 60 nm thick SiNX layer. We show that energies less than 15 kV and doses around 5 × 1015 cm-2 are appropriate to achieve open circuit voltage higher than 590 mV and efficiency around 16.7% on FZ-Si. The photovoltaic performances on ribbon silicon are so far limited by the bulk quality of the material and by the quality of the junction through the presence of silicon carbide precipitates at the surface. Nevertheless, we demonstrate that plasma immersion ion implantation is very promising for solar cell fabrication on ultrathin silicon wafers such as ribbons.

  17. Simultaneous Sterilization With Surface Modification Of Plastic Bottle By Plasma-Based Ion Implantation

    SciTech Connect

    Sakudo, N.; Ikenaga, N.; Ikeda, F.; Nakayama, Y.; Kishi, Y.; Yajima, Z.

    2011-01-07

    Dry sterilization of polymeric material is developed. The technique utilizes the plasma-based ion implantation which is same as for surface modification of polymers. Experimental data for sterilization are obtained by using spores of Bacillus subtilis as samples. On the other hand we previously showed that the surface modification enhanced the gas barrier characteristics of plastic bottles. Comparing the implantation conditions for the sterilization experiment with those for the surface modification, we find that both sterilization and surface modification are simultaneously performed in a certain range of implantation conditions. This implies that the present bottling system for plastic vessels will be simplified and streamlined by excluding the toxic peroxide water that has been used in the traditional sterilization processes.

  18. Enhanced osteogenic activity of poly ether ether ketone using calcium plasma immersion ion implantation.

    PubMed

    Lu, Tao; Qian, Shi; Meng, Fanhao; Ning, Congqin; Liu, Xuanyong

    2016-06-01

    As a promising implantable material, poly ether ether ketone (PEEK) possesses similar elastic modulus to that of cortical bones yet suffers from bio-inertness and poor osteogenic properties, which limits its application as orthopedic implants. In this work, calcium is introduced onto PEEK surface using calcium plasma immersion ion implantation (Ca-PIII). The results obtained from scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) confirm the modified layer with varying contents of calcium are formed on PEEK surfaces. Water contact angle measurements reveal the increasing hydrophobicity of both Ca-PIII treated surfaces. In vitro cell adhesion, viability assay, alkaline phosphatase activity and collagen secretion analyses disclose improved the adhesion, proliferation, and osteo-differentiation of rat bone mesenchymal stem cells (bMSCs) on Ca-PIII treated surfaces. The obtained results indicate that PEEK surface with enhanced osteogenic activity can be produced by calcium incorporation. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Simultaneous Sterilization With Surface Modification Of Plastic Bottle By Plasma-Based Ion Implantation

    NASA Astrophysics Data System (ADS)

    Sakudo, N.; Ikenaga, N.; Ikeda, F.; Nakayama, Y.; Kishi, Y.; Yajima, Z.

    2011-01-01

    Dry sterilization of polymeric material is developed. The technique utilizes the plasma-based ion implantation which is same as for surface modification of polymers. Experimental data for sterilization are obtained by using spores of Bacillus subtilis as samples. On the other hand we previously showed that the surface modification enhanced the gas barrier characteristics of plastic bottles. Comparing the implantation conditions for the sterilization experiment with those for the surface modification, we find that both sterilization and surface modification are simultaneously performed in a certain range of implantation conditions. This implies that the present bottling system for plastic vessels will be simplified and streamlined by excluding the toxic peroxide water that has been used in the traditional sterilization processes.

  20. Optimization of a plasma immersion ion implantation process for shallow junctions in silicon

    SciTech Connect

    Ray, Ashok; Nori, Rajashree; Bhatt, Piyush; Lodha, Saurabh; Pinto, Richard Rao, Valipe Ramgopal; Jomard, François; Neumann-Spallart, Michael

    2014-11-01

    A plasma immersion ion implantation (PIII) process has been developed for realizing shallow doping profiles of phosphorus and boron in silicon using an in-house built dual chamber cluster tool. High Si etch rates observed in a 5% PH{sub 3} in H{sub 2} plasma have been ascribed to high concentration of H(α) radicals. Therefore, subsequent work was carried out with 5% PH{sub 3} in He, leading to much smaller etch rates. By optical emission spectroscopy, the radical species H(α), PH*{sub 2}, and PH* have been identified. The concentration of all three species increased with pressure. Also, ion concentrations increased with pressure as evidenced by Langmuir data, with a maximum occurring at 0.12 mbar. The duty cycle of pulsed DC bias has a significant bearing on both the implantation and the etching process as it controls the leakage of positive charge collected at the surface of the silicon wafer during pulse on-time generated primarily due to secondary electron emission. The P implant process was optimized for a duty cycle of 10% or less at a pressure of 0.12 mbar with implant times as low as 30 s. Secondary ion mass spectroscopy showed a P dopant depth of 145 nm after rapid thermal annealing (RTA) at 950 °C for 5 s, resulting in a sheet resistance of 77 Ω/◻. Si n{sup +}/p diodes fabricated with phosphorus implantation using optimized PIII and RTA conditions exhibit J{sub on}/J{sub off} > 10{sup 6} with an ideality factor of nearly 1.2. Using similar conditions, shallow doping profiles of B in silicon have also been realized.

  1. Low-energy plasma immersion ion implantation to induce DNA transfer into bacterial E. coli

    NASA Astrophysics Data System (ADS)

    Sangwijit, K.; Yu, L. D.; Sarapirom, S.; Pitakrattananukool, S.; Anuntalabhochai, S.

    2015-12-01

    Plasma immersion ion implantation (PIII) at low energy was for the first time applied as a novel biotechnology to induce DNA transfer into bacterial cells. Argon or nitrogen PIII at low bias voltages of 2.5, 5 and 10 kV and fluences ranging from 1 × 1012 to 1 × 1017 ions/cm2 treated cells of Escherichia coli (E. coli). Subsequently, DNA transfer was operated by mixing the PIII-treated cells with DNA. Successes in PIII-induced DNA transfer were demonstrated by marker gene expressions. The induction of DNA transfer was ion-energy, fluence and DNA-size dependent. The DNA transferred in the cells was confirmed functioning. Mechanisms of the PIII-induced DNA transfer were investigated and discussed in terms of the E. coli cell envelope anatomy. Compared with conventional ion-beam-induced DNA transfer, PIII-induced DNA transfer was simpler with lower cost but higher efficiency.

  2. Fourth-generation plasma immersion ion implantation and deposition facility for hybrid surface modification layer fabrication

    SciTech Connect

    Wang Langping; Huang Lei; Xie Zhiwen; Wang Xiaofeng; Tang Baoyin

    2008-02-15

    The fourth-generation plasma immersion ion implantation and deposition (PIIID) facility for hybrid and batch treatment was built in our laboratory recently. Comparing with our previous PIIID facilities, several novel designs are utilized. Two multicathode pulsed cathodic arc plasma sources are fixed on the chamber wall symmetrically, which can increase the steady working time from 6 h (the single cathode source in our previous facilities) to about 18 h. Meanwhile, the inner diameter of the pulsed cathodic arc plasma source is increased from the previous 80 to 209 mm, thus, large area metal plasma can be obtained by the source. Instead of the simple sample holder in our previous facility, a complex revolution-rotation sample holder composed of 24 shafts, which can rotate around its axis and adjust its position through revolving around the center axis of the vacuum chamber, is fixed in the center of the vacuum chamber. In addition, one magnetron sputtering source is set on the chamber wall instead of the top cover in the previous facility. Because of the above characteristic, the PIIID hybrid process involving ion implantation, vacuum arc, and magnetron sputtering deposition can be acquired without breaking vacuum. In addition, the PIIID batch treatment of cylinderlike components can be finished by installing these components on the rotating shafts on the sample holder.

  3. Effects of carbon dioxide plasma immersion ion implantation on the electrochemical properties of AZ31 magnesium alloy in physiological environment

    NASA Astrophysics Data System (ADS)

    Xu, Ruizhen; Yang, Xiongbo; Zhang, Xuming; Wang, Mei; Li, Penghui; Zhao, Ying; Wu, Guosong; Chu, Paul K.

    2013-12-01

    Plasma immersion ion implantation (PIII) is conducted to improve the intrinsically poor corrosion properties of biodegradable AZ31 magnesium alloy in the physiological environment. Carbon dioxide is implanted into the samples and X-ray photoelectron spectroscopy and scanning electron microscopy are used to characterize the materials. The corrosion properties are systematically studied by potentiodynamic polarization tests in two simulated physiological environments, namely simulated body fluids and cell culture medium. The plasma-implanted materials exhibit a lower initial corrosion rate. Being a gaseous ion PIII technique, conformal ion implantation into an object with a complex shape such as an orthopedic implant can be easily accomplished and CO2 PIII is a potential method to improve the biological properties of magnesium and its alloys in clinical applications.

  4. Surface, electrical and mechanical modifications of PMMA after implantation with laser produced iron plasma ions

    NASA Astrophysics Data System (ADS)

    Ahmed, Qazi Salman; Bashir, Shazia; Jalil, Sohail Abdul; Shabbir, Muhammad Kaif; Mahmood, Khaliq; Akram, Mahreen; Khalid, Ayesha; Yaseen, Nazish; Arshad, Atiqa

    2016-07-01

    Laser Produced Plasma (LPP) was employed as an ion source for the modifications in surface, electrical and mechanical properties of poly methyl (methacrylate) PMMA. For this purpose Nd:YAG laser (532 nm, 6 ns, 10 Hz) at a fluence of 12.7 J/cm2 was employed to generate Fe plasma. The fluence and energy measurements of laser produced Fe plasma ions were carried out by employing Thomson Parabola Technique in the presence of magnetic field strength of 0.5 T, using CR-39 as Solid State Nuclear Track Detector (SSNTD). It has been observed that ion fluence ejecting from ablated plasma was maximum at an angle of 5° with respect to the normal to the Fe target surface. PMMA substrates were irradiated with Fe ions of constant energy of 0.85 MeV at various ion fluences ranging from 3.8 × 106 ions/cm2 to 1.8 × 108 ions/cm2 controlled by varying laser pulses from 3000 to 7000. Optical microscope and Scanning Electron Microscope (SEM) were utilized for the analysis of surface features of irradiated PMMA. Results depicted the formation of chain scission, crosslinking, dendrites and star like structures. To explore the electrical behavior, four probe method was employed. The electrical conductivity of ion irradiated PMMA was increased with increasing ion fluence. The surface hardness was measured by shore D hardness tester and results showed the monotonous increment in surface hardness with increasing ion fluence. The increasing trend of surface hardness and electrical conductivity with increasing Fe ion fluence has been well correlated with the surface morphology of ion implanted PMMA. The temperature rise of PMMA surface due to Fe ion irradiation is evaluated analytically and comes out to be in the range of 1.72 × 104 to 1.82 × 104 K. The values of total Linear Energy Transfer (LET) or stopping power of 0.8 MeV Fe ions in PMMA is 61.8 eV/Å and their range is 1.34 μm evaluated by SRIM simulation.

  5. Plasma immersion ion implantation modification of surface properties of polymer material

    SciTech Connect

    Husein, I.F.; Zhou, Y.; Qin, S.; Chan, C.; Marchev, K.; Kleiman, J.I.

    1997-12-01

    The use of plasma immersion ion implantation (PIII) as a novel method for the treatment of polymer surfaces is investigated. The effect of PIII treatment on the coefficient of friction, contact angle modification, and surface energy of silicone and EPDM (ethylene-propylene-diene monomer) rubber are investigated as a function of pulse voltage, treatment time, and gas species. Low energy (0--8 keV) and high dose ({approximately}10{sup 17}--10{sup 18} ions/cm{sup 2}) implantation of N{sub 2}, Ar, and CF{sub 4} is performed using an inductively coupled plasma source (ICP) at low pressure (0.2 mTorr). PIII treatment reduces the coefficient of friction ({micro}) of silicone rubber from {mu} = 0.464 to the range {mu} = 0.176--0.274, and {mu} of EPDM rubber decreases from 0.9 to the range {mu} = 0.27--0.416 depending on processing conditions. The contact angle of water and diiodomethylene decreases after implantation and increases at higher doses for both silicone and EPDM rubber.

  6. Plasma Immersion Ion Implantation for Interdigitated Back Passivated Contact (IBPC) Solar Cells

    SciTech Connect

    Young, David L.; Nemeth, William; LaSalvia, Vincenzo; Page, Matthew R.; Theingi, San; Young, Matthew; Aguiar, Jeffery; Lee, Benjamin G.; Stradins, Paul

    2016-11-21

    We present progress to develop low-cost interdigitated back contact solar cells with pc-Si/SiO2/c-Si passivated contacts formed by plasma immersion ion implantation (PIII). PIII is a lower-cost implantation technique than traditional beam-line implantation due to its simpler design, lower operating costs, and ability to run high doses (1E14-1E18 cm-2) at low ion energies (20 eV-10 keV). These benefits make PIII ideal for high throughput production of patterned passivated contacts, where high-dose, low-energy implantations are made into thin (20-200 nm) a-Si layers instead of into the wafer itself. For this work symmetric passivated contact test structures grown on n-Cz wafers with PH3 PIII doping gave implied open circuit voltage (iVoc) values of 730 mV with Jo values of 2 fA/cm2. Samples doped with B2H6 gave iVoc values of 690 mV and Jo values of 24 fA/cm2, outperforming BF3 doping, which gave iVoc values in the 660-680 mV range. Samples were further characterized by photoluminescence and SIMS depth profiles. Initial IBPC cell results are presented.

  7. Low-cost plasma immersion ion implantation doping for Interdigitated back passivated contact (IBPC) solar cells

    SciTech Connect

    Young, David L.; Nemeth, William; LaSalvia, Vincenzo; Page, Matthew R.; Theingi, San; Aguiar, Jeffery; Lee, Benjamin G.; Stradins, Paul

    2016-12-01

    We present progress to develop low-cost interdigitated back contact solar cells with pc-Si/SiO2/c-Si passivated contacts formed by plasma immersion ion implantation (PIII). PIII is a lower-cost implantation technique than traditional beam line implantation due to its simpler design, lower operating costs, and ability to run high doses (1E14-1E18 cm-2) at low ion energies (20 eV-10 keV). These benefits make PIII ideal for high throughput production of patterned passivated contacts, where high-dose, low-energy implantations are made into thin (20-200 nm) a-Si layers instead of into the wafer itself. For this work symmetric passivated contact test structures (~100 nm thick) grown on n-Cz wafers with pH3 PIII doping gave implied open circuit voltage (iVoc) values of 730 mV with Jo values of 2 fA/cm2. Samples doped with B2H6 gave iVoc values of 690 mV and Jo values of 24 fA/cm2, outperforming BF3 doping, which gave iVoc values in the 660-680 mV range. Samples were further characterized by SIMS, photoluminescence, TEM, EELS, and post-metallization TLM to reveal micro- and macro-scopic structural, chemical and electrical information.

  8. Low-cost plasma immersion ion implantation doping for Interdigitated back passivated contact (IBPC) solar cells

    DOE PAGES

    Young, David L.; Nemeth, William; LaSalvia, Vincenzo; ...

    2016-06-01

    Here, we present progress to develop low-cost interdigitated back contact solar cells with pc-Si/SiO2/c-Si passivated contacts formed by plasma immersion ion implantation (PIII). PIII is a lower-cost implantation technique than traditional beam line implantation due to its simpler design, lower operating costs, and ability to run high doses (1E14-1E18 cm-2) at low ion energies (20 eV-10 keV). These benefits make PIII ideal for high throughput production of patterned passivated contacts, where high-dose, low-energy implantations are made into thin (20-200 nm) a-Si layers instead of into the wafer itself. For this work symmetric passivated contact test structures (~100 nm thick) grownmore » on n-Cz wafers with pH3 PIII doping gave implied open circuit voltage (iVoc) values of 730 mV with Jo values of 2 fA/cm2. Samples doped with B2H6 gave iVoc values of 690 mV and Jo values of 24 fA/cm2, outperforming BF3 doping, which gave iVoc values in the 660-680 mV range. Samples were further characterized by SIMS, photoluminescence, TEM, EELS, and post-metallization TLM to reveal micro- and macro-scopic structural, chemical and electrical information.« less

  9. Ion behaviour in pulsed plasma regime by means of Time-resolved energy mass spectroscopy (TREMS) applied to an industrial radiofrequency Plasma Immersion Ion Implanter PULSION®

    NASA Astrophysics Data System (ADS)

    Carrere, M.; Torregrosa, F.; Kaeppelin, V.

    2006-11-01

    In order to face the requirements for P+/N junctions requested for < 45 nm ITRS nodes, new doping techniques are studied. Among them Plasma Immersion Ion Implantation (PIII) has been largely studied. IBS has designed and developed its own PIII machine named PULSION®. This machine is using a pulsed plasma. As other modem technological applications of low pressure plasma, PULSION® needs a precise control over plasma parameters in order to optimise process characteristics. In order to improve pulsed plasma discharge devoted to PIII, a nitrogen pulsed plasma has been studied in the inductively coupled plasma (ICP) of PULSION® and an argon pulsed plasma has been studied in the helicon discharge of the laboratory reactor of LPIIM (PHYSIS). Measurements of the Ion Energy Distribution Function (IEDF) with EQP300 (Hidden) have been performed in both pulsed plasma. This study has been done for different energies which allow to reconstruct the IEDF resolved in time (TREMS). By comparing these results, we found that the beginning of the plasma pulse, named ignition, exhaust at least three phases, or more. All these results allowed us to explain plasma dynamics during the pulse while observing transitions between capacitive and inductive coupling. This study leads in a better understanding of changes in discharge parameters as plasma potential, electron temperature, ion density.

  10. Plasma Immersion Ion Implantation with Solid Targets for Space and Aerospace Applications

    SciTech Connect

    Oliveira, R. M.; Goncalves, J. A. N.; Ueda, M.; Silva, G.; Baba, K.

    2009-01-05

    This paper describes successful results obtained by a new type of plasma source, named as Vaporization of Solid Targets (VAST), for treatment of materials for space and aerospace applications, by means of plasma immersion ion implantation and deposition (PIII and D). Here, the solid element is vaporized in a high pressure glow discharge, being further ionized and implanted/deposited in a low pressure cycle, with the aid of an extra electrode. First experiments in VAST were run using lithium as the solid target. Samples of silicon and aluminum alloy (2024) were immersed into highly ionized lithium plasma, whose density was measured by a double Langmuir probe. Measurements performed with scanning electron microscopy (SEM) showed clear modification of the cross-sectioned treated silicon samples. X-ray photoelectron spectroscopy (XPS) analysis revealed that lithium was implanted/deposited into/onto the surface of the silicon. Implantation depth profiles may vary according to the condition of operation of VAST. One direct application of this treatment concerns the protection against radiation damage for silicon solar cells. For the case of the aluminum alloy, X-ray diffraction analysis indicated the appearance of prominent new peaks. Surface modification of A12024 by lithium implantation/deposition can lower the coefficient of friction and improve the resistance to fatigue of this alloy. Recently, cadmium was vaporized and ionized in VAST. The main benefit of this element is associated with the improvement of corrosion resistance of metallic substrates. Besides lithium and cadmium, VAST allows to performing PIII and D with other species, leading to the modification of the near-surface of materials for distinct purposes, including applications in the space and aerospace areas.

  11. Plasma Immersion Ion Implantation with Solid Targets for Space and Aerospace Applications

    NASA Astrophysics Data System (ADS)

    Oliveira, R. M.; Gonçalves, J. A. N.; Ueda, M.; Silva, G.; Baba, K.

    2009-01-01

    This paper describes successful results obtained by a new type of plasma source, named as Vaporization of Solid Targets (VAST), for treatment of materials for space and aerospace applications, by means of plasma immersion ion implantation and deposition (PIII&D). Here, the solid element is vaporized in a high pressure glow discharge, being further ionized and implanted/deposited in a low pressure cycle, with the aid of an extra electrode. First experiments in VAST were run using lithium as the solid target. Samples of silicon and aluminum alloy (2024) were immersed into highly ionized lithium plasma, whose density was measured by a double Langmuir probe. Measurements performed with scanning electron microscopy (SEM) showed clear modification of the cross-sectioned treated silicon samples. X-ray photoelectron spectroscopy (XPS) analysis revealed that lithium was implanted/deposited into/onto the surface of the silicon. Implantation depth profiles may vary according to the condition of operation of VAST. One direct application of this treatment concerns the protection against radiation damage for silicon solar cells. For the case of the aluminum alloy, X-ray diffraction analysis indicated the appearance of prominent new peaks. Surface modification of A12024 by lithium implantation/deposition can lower the coefficient of friction and improve the resistance to fatigue of this alloy. Recently, cadmium was vaporized and ionized in VAST. The main benefit of this element is associated with the improvement of corrosion resistance of metallic substrates. Besides lithium and cadmium, VAST allows to performing PIII&D with other species, leading to the modification of the near-surface of materials for distinct purposes, including applications in the space and aerospace areas.

  12. Down to 2 nm Ultra Shallow Junctions : Fabrication by IBS Plasma Immersion Ion Implantation Prototype PULSION registered

    SciTech Connect

    Torregrosa, Frank; Etienne, Hasnaa; Mathieu, Gilles; Roux, Laurent

    2006-11-13

    Classical beam line implantation is limited in low energies and cannot achieve P+/N junctions requirements for <45nm node. Compared to conventional beam line ion implantation, limited to a minimum of about 200 eV, the efficiency of Plasma Immersion Ion Implantation (PIII) is no more to prove for the realization of Ultra Shallow Junctions (USJ) in semiconductor applications: this technique allows to get ultimate shallow profiles (as implanted) thanks to no lower limitation of energy and offers high dose rate. In the field of the European consortium NANOCMOS, Ultra Shallow Junctions implanted on a semi-industrial PIII prototype (PULSION registered ) designed by the French company IBS, have been studied. Ultra shallow junctions implanted with BF3 at acceleration voltages down to 20V were realized. Contamination level, homogeneity and depth profile are studied. The SIMS profiles obtained show the capability to make ultra shallow profiles (as implanted) down to 2nm.

  13. Effect of charge imbalance parameter on LEKW in ion-implanted quantum semiconductor plasmas

    SciTech Connect

    Chaudhary, Sandhya; Yadav, Nishchhal; Ghosh, S.

    2015-07-31

    In this study we present an analytical investigation on the propagation characteristics of electro-kinetic wave modified through quantum correction term and charge imbalance parameter using quantum hydrodynamic model for an ion-implanted semiconductor plasma. The dispersion relation has been analyzed in two distinct velocity regimes. We found that as the number of negative charges resides on the colloids increases, their role become increasing effective. The present investigation is important for understanding of wave and instability phenomena and can be put to various interesting applications.

  14. Improvement of nitrogen retained dose using ammonia as a precursor in nitrogen plasma immersion ion implantation of silicon

    SciTech Connect

    Wan, G.J.; Yang, P.; Fu, Ricky K.Y.; Yao, Zh.Q.; Huang, N.; Chu, Paul K.

    2005-09-15

    The low nitrogen retained dose due to competition from oxygen coimplantation diminishes the efficacy of nitrogen plasma immersion ion implantation in silicon. In this work, we aim at improving the nitrogen retained dose by using ammonia as a precursor. Ammonia is introduced into the nitrogen plasma during plasma immersion ion implantation of silicon to improve the nitrogen reactivity and reduce the competition from oxygen in the residual vacuum. Our x-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy results indicate that the ammonia precursor can indeed improve the N retained dose effectively, and the hydrophilic properties of the surface change with different ammonia to nitrogen ratios.

  15. Nitrogen Plasma Ion Implantation of Al and Ti alloys in the High Voltage Glow Discharge Mode

    NASA Astrophysics Data System (ADS)

    Oliveira, R. M.; Ueda, M.; Rossi, J. O.; Reuther, H.; Lepienski, C. M.; Beloto, A. F.

    2006-11-01

    Enhanced surface properties can be attained for aluminum and its alloys (mechanical and tribological) and Ti6Al4V (mainly tribological) by Plasma Immersion Ion Implantation (PIII) technique. The main problem here, more severe for Al case, is the rapid oxygen contamination even in low O partial pressure. High energy nitrogen ions during PIII are demanded for this situation, in order to enable the ions to pass through the formed oxide layer. We have developed a PIII system that can operate at energies in excess of 50keV, using a Stacked Blumlein (SB) pulser which can nominally provide up to 100 kV pulses. Initially, we are using this system in the High Voltage Glow Discharge (HVGD) mode, to implant nitrogen ions into Al5052 alloy with energies in the range of 30 to 50keV, with 1.5μs duration pulses at a repetition rate of 100Hz. AES, pin-on-disc, nanoindentation measurements are under way but x-ray diffraction results already indicated abundant formation of AlN in the surface for Al5052 treated with this HVGD mode. Our major aim in this PIII experiment is to achieve this difficult to produce stable and highly reliable AlN rich surface layer with high hardness, high corrosion resistance and very low wear rate.

  16. Nitrogen Plasma Ion Implantation of Al and Ti alloys in the High Voltage Glow Discharge Mode

    SciTech Connect

    Oliveira, R. M.; Ueda, M.; Rossi, J. O.; Reuther, H.; Lepienski, C. M.; Beloto, A. F.

    2006-11-13

    Enhanced surface properties can be attained for aluminum and its alloys (mechanical and tribological) and Ti6Al4V (mainly tribological) by Plasma Immersion Ion Implantation (PIII) technique. The main problem here, more severe for Al case, is the rapid oxygen contamination even in low O partial pressure. High energy nitrogen ions during PIII are demanded for this situation, in order to enable the ions to pass through the formed oxide layer. We have developed a PIII system that can operate at energies in excess of 50keV, using a Stacked Blumlein (SB) pulser which can nominally provide up to 100 kV pulses. Initially, we are using this system in the High Voltage Glow Discharge (HVGD) mode, to implant nitrogen ions into Al5052 alloy with energies in the range of 30 to 50keV, with 1.5{mu}s duration pulses at a repetition rate of 100Hz. AES, pin-on-disc, nanoindentation measurements are under way but x-ray diffraction results already indicated abundant formation of AlN in the surface for Al5052 treated with this HVGD mode. Our major aim in this PIII experiment is to achieve this difficult to produce stable and highly reliable AlN rich surface layer with high hardness, high corrosion resistance and very low wear rate.

  17. Experimental and theoretical investigation of the effects of sample size on copper plasma immersion ion implantation into polyethylene

    SciTech Connect

    Zhang Wei; Wu Zhengwei; Liu Chenglong; Pu Shihao; Zhang Wenjun; Chu, Paul K.

    2007-06-01

    Polymers are frequently surface modified to achieve special surface characteristics such as antibacterial properties, wear resistance, antioxidation, and good appearance. The application of metal plasma immersion ion implantation (PIII) to polymers is of practical interest as PIII offers advantages such as low costs, small instrument footprint, large area, and conformal processing capability. However, the insulating nature of most polymers usually leads to nonuniform plasma implantation and the surface properties can be adversely impacted. Copper is an antibacterial element and our previous experiments have shown that proper introduction of Cu by plasma implantation can significantly enhance the long-term antibacterial properties of polymers. However, lateral variations in the implant fluence and implantation depth across the insulating substrate can lead to inconsistent and irreproducible antibacterial effects. In this work, the influence of the sample size on the chemical and physical properties of copper plasma-implanted polyethylene is studied experimentally and theoretically using Poisson's equation and plasma sheath theory. Our results indicate that the sample size affects the implant depth profiles. For a large sample, more deposition occurs in the center region, whereas the implantation to deposition ratio shows less variation across the smaller sample. However, the Cu elemental chemical state is not affected by this variation. Our theoretical study discloses that nonuniform metal implantation mainly results from the laterally different surface potential on the insulating materials due to surface charge buildup and more effective charge transfer near the edge of the sample.

  18. Plasma immersion ion implantation of polyurethane shape memory polymer: Surface properties and protein immobilization

    NASA Astrophysics Data System (ADS)

    Cheng, Xinying; Kondyurin, Alexey; Bao, Shisan; Bilek, Marcela M. M.; Ye, Lin

    2017-09-01

    Polyurethane-type shape memory polymers (SMPU) are promising biomedical implant materials due to their ability to recover to a predetermined shape from a temporary shape induced by thermal activation close to human body temperature and their advantageous mechanical properties including large recovery strains and low recovery stresses. Plasma Immersion Ion Implantation (PIII) is a surface modification process using energetic ions that generates radicals in polymer surfaces leading to carbonisation and oxidation and the ability to covalently immobilise proteins without the need for wet chemistry. Here we show that PIII treatment of SMPU significantly enhances its bioactivity making SMPU suitable for applications in permanent implantable biomedical devices. Scanning Electron Microscopy (SEM), contact angle measurements, surface energy measurements, attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) were used to characterise the PIII modified surface, including its after treatment aging kinetics and its capability to covalently immobilise protein directly from solution. The results show a substantial improvement in wettability and dramatic changes of surface chemical composition dependent on treatment duration, due to the generation of radicals and subsequent oxidation. The SMPU surface, PIII treated for 200s, achieved a saturated level of covalently immobilized protein indicating that a full monolayer coverage was achieved. We conclude that PIII is a promising and efficient surface modification method to enhance the biocompatibility of SMPU for use in medical applications that demand bioactivity for tissue integration and stability in vivo.

  19. Ta-ion implantation induced by a high-intensity laser for plasma diagnostics and target preparation

    NASA Astrophysics Data System (ADS)

    Cutroneo, M.; Malinsky, P.; Mackova, A.; Matousek, J.; Torrisi, L.; Slepicka, P.; Ullschmied, J.

    2015-12-01

    The present work is focused on the implantation of Ta ions into silicon substrates covered by a silicon dioxide layer 50-300 nm thick. The implantation is achieved using sub-nanosecond pulsed laser ablation (1015 W/cm2) with the objective of accelerating non-equilibrium plasma ions. The accelerated Ta ions are implanted into the exposed silicon substrates at energies of approximately 20 keV per charge state. By changing a few variables in the laser pulse, it is possible to control the kinetic energy, the yield and the angular distribution of the emitted ions. Rutherford Back-Scattering analysis was performed using 2.0 MeV He+ as the probe ions to determine the elemental depth profiles and the chemical composition of the laser-implanted substrates. The depth distributions of the implanted Ta ions were compared to SRIM 2012 simulations. The evaluated results of energy distribution were compared with online techniques, such as Ion Collectors (IC) and an Ion Energy Analyser (IEA), for a detailed identification of the produced ion species and their energy-to-charge ratios (M/z). Moreover, XPS (X-ray Photon Spectroscopy) and AFM (Atomic Force Microscopy) analyses were carried out to obtain information on the surface morphology and the chemical composition of the modified implanted layers, as these features are important for further application of such structures.

  20. Oxygen plasma immersion ion implantation treatment to enhance data retention of tungsten nanocrystal nonvolatile memory

    SciTech Connect

    Wang, Jer-Chyi Chang, Wei-Cheng; Lai, Chao-Sung; Chang, Li-Chun; Ai, Chi-Fong; Tsai, Wen-Fa

    2014-03-15

    Data retention characteristics of tungsten nanocrystal (W-NC) memory devices using an oxygen plasma immersion ion implantation (PIII) treatment are investigated. With an increase of oxygen PIII bias voltage and treatment time, the capacitance–voltage hysteresis memory window is increased but the data retention characteristics become degraded. High-resolution transmission electron microscopy images show that this poor data retention is a result of plasma damage on the tunneling oxide layer, which can be prevented by lowering the bias voltage to 7 kV. In addition, by using the elevated temperature retention measurement technique, the effective charge trapping level of the WO{sub 3} film surrounding the W-NCs can be extracted. This measurement reveals that a higher oxygen PIII bias voltage and treatment time induces more shallow traps within the WO{sub 3} film, degrading the retention behavior of the W-NC memory.

  1. STEM observation of nano-interface between substrate and DLC film prepared by plasma-based ion implantation and deposition

    NASA Astrophysics Data System (ADS)

    Oka, Y.; Nishijima, M.; Hiraga, K.; Yatsuzuka, M.

    2007-04-01

    This paper discusses the nano-interface between an aluminum alloy (A5052) substrate and diamond-like carbon (DLC) film prepared by a hybrid process of plasma-based ion implantation and deposition (PBIID) using superimposed RF and negative high-voltage pulses. Adhesion strength of DLC films were enhanced by carbon ion implantation to the substrate. The nano-interface between DLC film and substrate was observed by high resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) and analyzed by energy dispersive X-ray spectroscopy (EDS). It was found that an unclear crystal structure damaged by ion implantation was formed in the carbon ion-implanted layer. Besides, the amorphous mixing layer of oxide and DLC was produced on the substrate surface. The formation of the mixing layer, the layer of unclear crystal structure and the destruction of oxide led to the enhancement in adhesion strength of DLC film.

  2. Low-cost plasma immersion ion implantation doping for Interdigitated back passivated contact (IBPC) solar cells

    SciTech Connect

    Young, David L.; Nemeth, William; LaSalvia, Vincenzo; Page, Matthew R.; Theingi, San; Aguiar, Jeffery; Lee, Benjamin G.; Stradins, Paul

    2016-06-01

    Here, we present progress to develop low-cost interdigitated back contact solar cells with pc-Si/SiO2/c-Si passivated contacts formed by plasma immersion ion implantation (PIII). PIII is a lower-cost implantation technique than traditional beam line implantation due to its simpler design, lower operating costs, and ability to run high doses (1E14-1E18 cm-2) at low ion energies (20 eV-10 keV). These benefits make PIII ideal for high throughput production of patterned passivated contacts, where high-dose, low-energy implantations are made into thin (20-200 nm) a-Si layers instead of into the wafer itself. For this work symmetric passivated contact test structures (~100 nm thick) grown on n-Cz wafers with pH3 PIII doping gave implied open circuit voltage (iVoc) values of 730 mV with Jo values of 2 fA/cm2. Samples doped with B2H6 gave iVoc values of 690 mV and Jo values of 24 fA/cm2, outperforming BF3 doping, which gave iVoc values in the 660-680 mV range. Samples were further characterized by SIMS, photoluminescence, TEM, EELS, and post-metallization TLM to reveal micro- and macro-scopic structural, chemical and electrical information.

  3. Mechanical Properties of Plasma Immersion Ion Implanted PEEK for Bioactivation of Medical Devices.

    PubMed

    Wakelin, Edgar A; Fathi, Ali; Kracica, Masturina; Yeo, Giselle C; Wise, Steven G; Weiss, Anthony S; McCulloch, Dougal G; Dehghani, Fariba; Mckenzie, David R; Bilek, Marcela M M

    2015-10-21

    Plasma immersion ion implantation (PIII) is used to modify the surface properties of polyether ether ketone for biomedical applications. Modifications to the mechanical and chemical properties are characterized as a function of ion fluence (treatment time) to determine the suitability of the treated surfaces for biological applications. Young's modulus and elastic recovery were found to increase with respect to treatment time at the surface from 4.4 to 5.2 MPa and from 0.49 to 0.68, respectively. The mechanical properties varied continuously with depth, forming a graded layer where the mechanical properties returned to untreated values deep within the layer. The treated surface layer exhibited cracking under cyclical loads, associated with an increased modulus due to dehydrogenation and cross-linking; however, it did not show any sign of delamination, indicating that the modified layer is well integrated with the substrate, a critical factor for bioactive surface coatings. The oxygen concentration remained unchanged at the surface; however, in contrast to ion implanted polymers containing only carbon and hydrogen, the oxygen concentration within the treated layer was found to decrease. This effect is attributed to UV exposure and suggests that PIII treatments can modify the surface to far greater depths than previously reported. Protein immobilization on PIII treated surfaces was found to be independent of treatment time, indicating that the surface mechanical properties can be tuned for specific applications without affecting the protein coverage. Our findings on the mechanical properties demonstrate such treatments render PEEK well suited for use in orthopedic implantable devices.

  4. Bio-functionalisation of polyether ether ketone using plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Wakelin, Edgar; Yeo, Giselle; Kondyurin, Alexey; Davies, Michael; McKenzie, David; Weiss, Anthony; Bilek, Marcela

    2015-12-01

    Plasma immersion ion implantation (PIII) is used here to improve the surface bioactivity of polyether ether ketone (PEEK) by modifying the chemical and mechanical properties and by introducing radicals. Modifications to the chemical and mechanical properties are characterised as a function of ion fluence (proportional to treatment time) to determine the suitability of the treated surfaces for biological applications. Radical generation increases with treatment time, where treatments greater than 400 seconds result in a high concentration of long-lived radicals. Radical reactions are responsible for oxidation of the surface, resulting in a permanent increase in the polar surface energy. The nano-scale reduced modulus was found to increase with treatment time at the surface from 4.4 to 5.2 GPa. The macromolecular Young's modulus was also found to increase, but by an amount corresponding to the volume fraction of the ion implanted region. The treated surface layer exhibited cracking under cyclical loads, associated with an increased modulus due to dehydrogenation and crosslinking, however it did not show any sign of delamination, indicating that the modified layer is well integrated with the substrate - a critical factor for bioactive surface coatings to be used in-vivo. Protein immobilisation on the PIII treated surfaces was found to saturate after 240 seconds of treatment, indicating that there is room to tune surface mechanical properties for specific applications without affecting the protein coverage. Our findings indicate that the modification of the chemical and mechanical properties by PIII treatments as well as the introduction of radicals render PEEK well suited for use in orthopaedic implantable devices.

  5. Experimental study on a new sterilization process using plasma source ion implantation with N2 gas

    NASA Astrophysics Data System (ADS)

    Yoshida, M.; Tanaka, T.; Watanabe, S.; Takagi, T.; Shinohara, M.; Fujii, S.

    2003-07-01

    Plasma source ion implantation (PSII) with negative high voltage pulses has been applied to the sterilization process as a technique suitable for sterilization of three-dimensional work pieces. Pulsed high negative voltage (0-10 μs pulse width, 900 pulses/s, -9 to -16 kV) was applied to the electrode in this process at a gas pressure of 2-7 Pa of N2. This process has been found to be capable of generating glow discharge plasma around a stainless electrode, on which quartz glass samples with biological materials are placed. We found that the PSII process reduced the numbers of active Bacillus pumilus cells using N2 gas plasma generated by pulsed dc voltages. The number of bacteria survivors was reduced by 105×with 5-10 min exposure. The state of cells on quartz glass was observed by scanning electron microscopy with and without exposure. We found that the ion energy is the most important processing parameter. The technique is demonstrated to be an effective means of low-temperature surface sterilization, with very little damage to the target.

  6. The generation, detection and measurement of laser-induced carbon plasma ions and their implantation effects on brass substrate

    NASA Astrophysics Data System (ADS)

    Ahmad, Shahbaz; Bashir, Shazia; Shahid Rafique, M.; Yousaf, Daniel; Ahmad, Riaz

    2016-05-01

    The generation, detection and measurement of laser-induced carbon plasma ions and their implantation effects on brass substrate have been investigated. Thomson parabola technique was employed to measure the energy and flux of carbon ions. The magnetic field of strength 80 mT was applied on the graphite plasma plume to provide an appropriate trajectory to the generated ions. The energy of carbon ions is 678 KeV for laser fluence of 5.1 J/cm2 which was kept constant for all exposures. The flux of ions varies from 32 × 1011 to 72 × 1014 ions/cm2 for varying numbers of laser pulses from 3000 to 12,000. In order to explore the ion irradiation effects on brass, four brass substrates were irradiated by carbon ions of different flux. Scanning electron microscope (SEM) and X-ray diffractometer (XRD) are used to analyze the surface morphology and crystallographic structure of ion-implanted brass, respectively. SEM analysis reveals the formation and growth of nano-/micro-sized cavities, pores and pits for the various ion flux for varying numbers of laser pulses from 3000 to 12,000. By increasing ion flux by increasing the number of pulses up to 9000 shots, the dendritic structures initiate to grow along with cavities and pores. At the maximum ion flux for 12,000 shots, the unequiaxed dendritic structures become distinct and the distance between the dendrites is decreased, whereas cavities, pores and pits are completely finished. The XRD analysis reveals that a new phase of ZnC (0012) is formed in the brass substrate after ion implantation. Universal tensile testing machine and Vickers microhardness tester are used to explore the yield stress, ultimate tensile strength and microhardness of ion-implanted brass substrate. The mechanical properties monotonically increase by increasing the ion flux. Variations in mechanical properties are correlated with surface and structural modifications of brass.

  7. Enhanced osteoblast responses to poly ether ether ketone surface modified by water plasma immersion ion implantation.

    PubMed

    Wang, Heying; Lu, Tao; Meng, Fanhao; Zhu, Hongqin; Liu, Xuanyong

    2014-05-01

    Poly ether ether ketone (PEEK) offers a set of characteristics superior for human implants; however, its application is limited by the bio-inert surface property. In this work, PEEK surface was modified using single step plasma immersion ion implantation (PIII) treatment with a gas mixture of water vapor as a plasma resource and argon as an ionization assistant. Field emission scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy were used to investigate the microstructure and composition of the modified PEEK surface. The water contact angle and zeta-potential of the surfaces were also measured. Osteoblast precursor cells MC3T3-E1 and rat bone mesenchymal stem cells were cultured on the PEEK samples to evaluate their cytocompatibility. The obtained results show that the hydroxyl groups as well as a "ravined structure" are constructed on water PIII modified PEEK. Compared with pristine PEEK, the water PIII treated PEEK is more favorable for osteoblast adhesion, spreading and proliferation, besides, early osteogenic differentiation indicated by the alkaline phosphatase activity is also up-regulated. Our study illustrates enhanced osteoblast responses to the PEEK surface modified by water PIII, which gives positive information in terms of future biomedical applications.

  8. Amplitude modulation and demodulation of an electromagnetic wave in magnetized ion-implanted semiconductor plasmas having SDDC

    NASA Astrophysics Data System (ADS)

    Yadav, N.; Ghosh, S.; Malviya, P. S.

    2017-05-01

    In communication processes, amplitude modulation is very helpful to save power using a single band transmission. Using the hydrodynamical description of semiconductor plasma analytical investigations are made for the amplitude modulation as well as demodulation of an electromagnetic wave in magnetized ion implanted semiconductor plasmas having strain dependent dielectric constants. Analysis is made under different wave number regimes over a wide range of cyclotron frequencies without and with colloids. Numerical estimations are made for n-doped BaTiO3 crystal irradiated by pump wave frequency 1.78 × 1013s-1. It has been found that ion implantation of negatively charged colloids modifies nearly ≈ 105 of magnitude of amplitude modulation and demodulation processes. Ion implantation plays a key role in development of optoelectronics.

  9. Si-nanocrystal-based LEDs fabricated by ion implantation and plasma-enhanced chemical vapour deposition.

    PubMed

    Perálvarez, M; Barreto, J; Carreras, Josep; Morales, A; Navarro-Urrios, D; Lebour, Y; Domínguez, C; Garrido, B

    2009-10-07

    An in-depth study of the physical and electrical properties of Si-nanocrystal-based MOSLEDs is presented. The active layers were fabricated with different concentrations of Si by both ion implantation and plasma-enhanced chemical vapour deposition. Devices fabricated by ion implantation exhibit a combination of direct current and field-effect luminescence under a bipolar pulsed excitation. The onset of the emission decreases with the Si excess from 6 to 3 V. The direct current emission is attributed to impact ionization and is associated with the reasonably high current levels observed in current-voltage measurements. This behaviour is in good agreement with transmission electron microscopy images that revealed a continuous and uniform Si nanocrystal distribution. The emission power efficiency is relatively low, approximately 10(-3)%, and the emission intensity exhibits fast degradation rates, as revealed from accelerated ageing experiments. Devices fabricated by chemical deposition only exhibit field-effect luminescence, whose onset decreases with the Si excess from 20 to 6 V. The absence of the continuous emission is explained by the observation of a 5 nm region free of nanocrystals, which strongly reduces the direct current through the gate. The main benefit of having this nanocrystal-free region is that tunnelling current flow assisted by nanocrystals is blocked by the SiO2 stack so that power consumption is strongly reduced, which in return increases the device power efficiency up to 0.1%. In addition, the accelerated ageing studies reveal a 50% degradation rate reduction as compared to implanted structures.

  10. Adherent diamond like carbon coatings on metals via plasma source ion implantation

    SciTech Connect

    Walter, K.C.; Nastasi, M.; Munson, C.P.

    1996-12-01

    Various techniques are currently used to produce diamond-like carbon (DLC) coatings on various materials. Many of these techniques use metallic interlayers, such as Ti or Si, to improve the adhesion of a DLC coating to a ferrous substrate. An alternative processing route would be to use plasma source ion implantation (PSII) to create a carbon composition gradient in the surface of the ferrous material to serve as the interface for a DLC coating. The need for interlayer deposition is eliminated by using a such a graded interfaces PSII approach has been used to form adherent DLC coatings on magnesium, aluminum, silicon, titanium, chromium, brass, nickel, and tungsten. A PSII process tailored to create a graded interface allows deposition of adherent DLC coatings even on metals that exhibit a positive heat of formation with carbon, such as magnesium, iron, brass and nickel.

  11. Enhanced cytocompatibility and reduced genotoxicity of polydimethylsiloxane modified by plasma immersion ion implantation.

    PubMed

    Tong, Liping; Zhou, Wenhua; Zhao, Yuetao; Yu, Xuefeng; Wang, Huaiyu; Chu, Paul K

    2016-12-01

    Polydimethylsiloxane(PDMS) is a common industrial polymer with advantages such as ease of fabrication, tunable hardness, and other desirable properties, but the basic (-OSi(CH3)2-)n structure in PDMS is inherently hydrophobic thereby hampering application to biomedical engineering. In this study, plasma immersion ion implantation (PIII) is conducted on PDMS to improve the biological properties. PIII forms wrinkled "herringbone" patterns and abundant O-containing functional groups on PDMS to alter the surface hydrophilicity. The biocompatibility of the modified PDMS is assessed with Chinese hamster ovarian cells and compared to that of the untreated PDMS. Our results reveal that the PDMS samples after undergoing PIII have better cytocompatibility and lower genotoxicity. PIII which is a non-line-of-sight technique extends the application of PDMS to the biomedical field.

  12. Enhancement of surface properties of 45{number_sign} steel using plasma immersion ion implantation

    SciTech Connect

    Wang, S.Y.; Tian, X.B. |; Chu, P.K.; Wang, X.F.; Liu, A.G.; Tang, B.Y.; Zeng, X.C.; Lin, Q.Z.

    1997-12-31

    45{number_sign} steel, which has good mechanical strength and is relatively cheap, is a common constituent in industrial components, such as precision gears, piston columns of oil pumps, and so on. However, since the working environment of these industrial parts is sometimes quite harsh and unforgiving, they are vulnerable to wear and corrosion. Replacing 45{number_sign} steel with stainless or alloy steel increases the cost significant, and a better alternative is to improve its surface properties and lifetime using plasma immersion ion implantation (PIII). The authors have devised a variety of treatment processes using PIII, including radio-frequency (RF) plasma nitriding, RF plasma nitriding and nitrogen PIII, Ti deposition in conjunction with nitrogen PIII (IBED), as well as Cr deposition followed by nitrogen PIII (IBED). To assess the efficacy of the processes, the microhardness and mass loss due to wear were measured for both the untreated and treated 45{number_sign} samples. A salt fog test was also conducted to evaluate the resistance against rusting. The experimental results show that the microhardness and resistance against rusting of the treated 45{number_sign} steel samples are much improved, and the mass loss due to wear is reduced substantially. In this paper, the authors compare the effectiveness of each treatment technique in addition to showing supporting data.

  13. A hybrid model for simulation of secondary electron emission in plasma immersion ion implantation under different pulse rise time

    SciTech Connect

    Navab Safa, N. Ghomi, H.

    2015-02-15

    A hybrid fluid Particle in Cell–Monte Carlo Collision (PiC–MCC) model is presented to study the effect of secondary electron emission on the plasma immersion ion implantation process under different pulse rise time. The model describes the temporal evolution of various parameters of plasma such as ion density, ion velocity, secondary electron density, and secondary electron current for different rise times. A 3D–3 V PiC–MCC model is developed to simulate the secondary electrons which are emitted from the sample surface while the plasma ions and electrons are treated using a 1D fluid model. The simulation results indicate that the secondary electron density and secondary electron current increase as the rise time decreases. The main differences between the results for different rise times are found during the initial phase of the pulse. The results are explained through studying the fundamental parameters of plasma.

  14. Preparation of plastic and biopolymer multilayer films by plasma source ion implantation.

    PubMed

    Shin, Gye Hwa; Lee, Yeon Hee; Lee, Jin Sil; Kim, Young Soo; Choi, Won Seok; Park, Hyun Jin

    2002-07-31

    The plasma source ion implantation (PSII) technique was used to improve the adhesion between linear low-density polyethylene (LLDPE) and biopolymer. LLDPE was treated with the PSII using O(2) or CF(4) gas to modify its surface. After modification, chitosan or corn zein was used for coating on LLDPE. Wettability of the LLDPE surface was evaluated with a contact angle meter by the sessile drop method. X-ray photoelectron spectroscopy (XPS) was used to analyze the LLDPE surface. Before and after treatment, in the case of LLDPE treated with O(2) PSII, oxygen-containing functional groups were formed on the implanted surface. In the CF(4) PSII treated LLDPE, it was observed that the fluorine concentration on the surface of LLDPE remarkably increased and hydrophobic groups were formed by chemical reaction. Bilayer films coated with chitosan or corn zein showed 10 times lower oxygen permeability. Tensile strength of multilayer films was decreased a little compared with that of LLDPE. The plastic and biopolymer multilayer films have potential for food packaging application because of their O(2) gas barrier property and easy recyclability of the multilayer film.

  15. Proliferation and differentiation of osteoblastic cells on titanium modified by ammonia plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Liu, Fei; Li, Bin; Sun, Junying; Li, Hongwei; Wang, Bing; Zhang, Shailin

    2012-03-01

    We report here a new method of titanium surface modification through ammonia (NH3) plasma immersion ion implantation (PIII) technique and its effect on the cellular behaviors of MC3T3-E1 osteoblastic cells. The NH3 PIII-treated titanium substrates (NH3-Ti) were characterized by X-ray photoelectron (XPS), which showed that NH3-Ti had a nitrogen-rich surface. However, there was no significant difference between the surface morphology of NH3-Ti and unmodified Ti. When MC3T3-E1 cells were cultured on NH3-Ti substrates, it was found that cell proliferation was accelerated at 4 and 7 days of culture. Meanwhile, cell differentiation was evaluated using type I collagen (COL I), osteocalcin (OC) and bone sialoprotein (BSP) as differentiation markers. It was found that expression of COL I and OC genes was up-regulated on NH3-Ti substrates. However, no significant difference was found in BSP gene expression between NH3-Ti and unmodified Ti substrates. Therefore, findings from this study indicate that surface modification of titanium through NH3 PIII favors osteoblastic proliferation and differentiation and as a result, it may be used to improve the biocompatibility of Ti implants in vivo.

  16. Surface modification of biomaterials using plasma immersion ion implantation and deposition

    PubMed Central

    Lu, Tao; Qiao, Yuqin; Liu, Xuanyong

    2012-01-01

    Although remarkable progress has been made on biomaterial research, the ideal biomaterial that satisfies all the technical requirements and biological functions is not available up to now. Surface modification seems to be a more economic and efficient way to adjust existing conventional biomaterials to meet the current and ever-evolving clinical needs. From an industrial perspective, plasma immersion ion implantation and deposition (PIII&D) is an attractive method for biomaterials owing to its capability of treating objects with irregular shapes, as well as the control of coating composition. It is well acknowledged that the physico-chemical characteristics of biomaterials are the decisive factors greatly affecting the biological responses of biomaterials including bioactivity, haemocompatibility and antibacterial activity. Here, we mainly review the recent advances in surface modification of biomaterials via PIII&D technology, especially titanium alloys and polymers used for orthopaedic, dental and cardiovascular implants. Moreover, the variations of biological performances depending on the physico-chemical properties of modified biomaterials will be discussed. PMID:23741609

  17. In Vitro Corrosion Behavior and Apatite Growth of Oxygen Plasma Ion Implanted Titanium Alloy β-21S

    NASA Astrophysics Data System (ADS)

    Anandan, C.; Mohan, L.

    2013-11-01

    Titanium alloy beta 21S was implanted with oxygen ions by plasma immersion ion implantation. The implanted surface was characterized by micro-Raman, XPS and FESEM before and after potentiodynamic polarization and electrochemical impedance studies in Hanks' solution and after incubation in Hanks' solution for 1 and 7 days. The investigations show that the native oxide on the sample is replaced by a compact oxide by implantation and the new oxide layer behaves in a different way in that a two layer model is required to explain the observed electrochemical impedance data. The analysis of layers formed in the electrochemical studies and after incubation in Hanks' solution by XPS and FESEM shows that the new oxide surface is capable of inducing apatite growth on it.

  18. Temperature dependent properties of silicon containing diamondlike carbon films prepared by plasma source ion implantation

    NASA Astrophysics Data System (ADS)

    Hatada, R.; Flege, S.; Baba, K.; Ensinger, W.; Kleebe, H.-J.; Sethmann, I.; Lauterbach, S.

    2010-04-01

    Silicon containing diamondlike carbon (Si-DLC) films were prepared on silicon wafer substrates by a plasma source ion implantation method with negative pulses superposed on a negative dc voltage. A mixture of acetylene and tetramethylsilane gas was introduced into the discharge chamber as working gases for plasma formation. Ions produced in the plasma are accelerated toward a substrate holder because of the negative voltage applied directly to it. After deposition, the films were annealed for 0.5 h in ambient air at temperatures up to 923 K in order to evaluate the thermal stability of the Si-DLC films. The films were analyzed by x-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy, and Raman spectroscopy. The surface morphology of the films and the film thickness were observed by atomic force microscopy and scanning electron microscopy. The mechanical and tribological properties were investigated by an indentation method and a ball-on-disk test. The results show the silicon containing DLC films were amorphous and the surface roughness of the Si containing DLC films was very smooth and no special structure was observed. Integrated intensity ratios ID/IG of Raman spectroscopy of the Si containing DLC films decreased with Si content. The Raman spectra showed that the structure of the Si-free DLC film changed to a graphitelike structure with increasing annealing temperature, whereas that of the 24 at. % Si containing DLC films did not change at the maximum temperature used in this study. A very low friction coefficient was obtained for the 13 at. % Si containing DLC film. The surface roughness and the hardness of the films changed with increasing annealing temperature. The formation of Si oxide in a near surface layer was confirmed by XPS and it prevents further oxidation of the inside of the film. Heat resistivity of DLC films can be improved by Si addition into the DLC films.

  19. Plasma-based ion implantation: a valuable technology for the elaboration of innovative materials and nanostructured thin films

    NASA Astrophysics Data System (ADS)

    Vempaire, D.; Pelletier, J.; Lacoste, A.; Béchu, S.; Sirou, J.; Miraglia, S.; Fruchart, D.

    2005-05-01

    Plasma-based ion implantation (PBII), invented in 1987, can now be considered as a mature technology for thin film modification. After a brief recapitulation of the principle and physics of PBII, its advantages and disadvantages, as compared to conventional ion beam implantation, are listed and discussed. The elaboration of thin films and the modification of their functional properties by PBII have already been achieved in many fields, such as microelectronics (plasma doping/PLAD), biomaterials (surgical implants, bio- and blood-compatible materials), plastics (grafting, surface adhesion) and metallurgy (hard coatings, tribology), to name a few. The major advantages of PBII processing lie, on the one hand, in its flexibility in terms of ion implantation energy (from 0 to 100 keV) and operating conditions (plasma density, collisional or non-collisional ion sheath), and, on the other hand, in the easy transferrability of processes from the laboratory to industry. The possibility of modifying the composition and physical nature of the films, or of drastically changing their physical properties over several orders of magnitude makes this technology very attractive for the elaboration of innovative materials, including metastable materials, and the realization of micro- or nanostructures. A review of the state of the art in these domains is presented and illustrated through a few selected examples. The perspectives opened up by PBII processing, as well as its limitations, are discussed.

  20. Osteoblast behavior on polytetrafluoroethylene modified by long pulse, high frequency oxygen plasma immersion ion implantation.

    PubMed

    Wang, Huaiyu; Kwok, Dixon T K; Wang, Wei; Wu, Zhengwei; Tong, Liping; Zhang, Yumei; Chu, Paul K

    2010-01-01

    Polytetrafluoroethylene (PTFE) is a commonly used medical polymer due to its biological stability and other attractive properties such as high hardness and wear resistance. However, the low surface energy and lack of functional groups to interact with the cellular environment have severely limited its applications in bone or cartilage replacements. Plasma immersion ion implantation (PIII) is a proven effective surface modification technique. However, when conducted on polymeric substrates, conventional PIII experiments typically employ a low pulsing frequency and short pulse duration in order to avoid sample overheating, charging, and plasma sheath extension. In this paper, a long pulse, high frequency O(2) PIII process is described to modify PTFE substrates by implementing a shielded grid in the PIII equipment without these aforementioned adverse effects. X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and contact angle measurements are carried out to reveal the surface effects of PTFE after long pulse, high frequency O(2) PIII and the results are compared to those obtained from conventional short pulse, low frequency O(2) PIII, O(2) plasma immersion, and the untreated control samples. Our results show that less oxygen-containing, rougher, and more hydrophobic surfaces are produced on PTFE after long pulse, high frequency O(2) PIII compared to the other 2 treatments. Cell viability assay, ALP activity test, and real-time PCR analysis are also performed to investigate the osteoblast behavior. It is clear that all 3 surface modification techniques promote osteoblast adhesion and proliferation on the PTFE substrates. Improvements on the ALP, OPN, and ON expression of the seeded osteoblasts are also obvious. However, among these treatments, only long pulse, high frequency O(2) PIII can promote the OCN expression of osteoblasts when the incubation time is 12 days. Our data unequivocally disclose that the long pulse, high frequency O(2) PIII

  1. Performance improvement of gadolinium oxide resistive random access memory treated by hydrogen plasma immersion ion implantation

    SciTech Connect

    Wang, Jer-Chyi Hsu, Chih-Hsien; Ye, Yu-Ren; Ai, Chi-Fong; Tsai, Wen-Fa

    2014-03-15

    Characteristics improvement of gadolinium oxide (Gd{sub x}O{sub y}) resistive random access memories (RRAMs) treated by hydrogen plasma immersion ion implantation (PIII) was investigated. With the hydrogen PIII treatment, the Gd{sub x}O{sub y} RRAMs exhibited low set/reset voltages and a high resistance ratio, which were attributed to the enhanced movement of oxygen ions within the Gd{sub x}O{sub y} films and the increased Schottky barrier height at Pt/Gd{sub x}O{sub y} interface, respectively. The resistive switching mechanism of Gd{sub x}O{sub y} RRAMs was dominated by Schottky emission, as proved by the area dependence of the resistance in the low resistance state. After the hydrogen PIII treatment, a retention time of more than 10{sup 4} s was achieved at an elevated measurement temperature. In addition, a stable cycling endurance with the resistance ratio of more than three orders of magnitude of the Gd{sub x}O{sub y} RRAMs can be obtained.

  2. Note: Sample holder with open area for increased deposition rate in plasma immersion ion implantation and deposition

    NASA Astrophysics Data System (ADS)

    Flege, S.; Hatada, R.; Derepa, A.; Dietz, C.; Ensinger, W.; Baba, K.

    2017-09-01

    A sample holder with a large open area offers several benefits when used in the process of plasma immersion ion implantation and deposition in which the plasma is generated by a high voltage applied to the sample holder: The ignition voltage of the plasma is lower, and the deposition rate can be several times higher than in the case of a normal plate-like holder. There is a more pronounced edge effect regarding the film thickness. Other film properties are also affected; for diamond-like carbon films, the film structure exhibits more disorder. The hardness of the samples is similar, with the surfaces of the samples being very smooth.

  3. Physics of Plasma-Based Ion Implantation&Deposition (PBIID)and High Power Impulse Magnetron Sputtering (HIPIMS): A Comparison

    SciTech Connect

    Anders, Andre

    2007-08-28

    The emerging technology of High Power Impulse MagnetronSputtering (HIPIMS) has much in common with the more establishedtechnology of Plasma Based Ion Implantation&Deposition (PBIID):both use pulsed plasmas, the pulsed sheath periodically evolves andcollapses, the plasma-sheath system interacts with the pulse-drivingpower supply, the plasma parameters are affected by the power dissipated,surface atoms are sputtered and secondary electrons are emitted, etc.Therefore, both fields of science and technology could learn from eachother, which has not been fully explored. On the other hand, there aresignificant differences, too. Most importantly, the operation of HIPIMSheavilyrelies on the presence of a strong magnetic field, confiningelectrons and causing their ExB drift, which is closed for typicalmagnetron configurations. Second, at the high peak power levels used forHIPIMS, 1 kW/cm2 or greater averaged over the target area, the sputteredmaterial greatly affects plasma generation. For PBIID, in contrast,plasma generation and ion processing of the surface (ion implantation,etching, and deposition) are considered rela-tively independentprocesses. Third, secondary electron emission is generally considered anuisance for PBIID, especially at high voltages, whereas it is a criticalingredient to the operation of HIPIMS. Fourth, the voltages in PBIID areoften higher than in HIPIMS. For the first three reasons listed above,modelling of PBIID seems to be easier and could give some guidance forfuture HIPIMS models, which, clearly, will be more involved.

  4. Cluster of differentiation antibody microarrays on plasma immersion ion implanted polycarbonate.

    PubMed

    Kosobrodova, E; Mohamed, A; Su, Y; Kondyurin, A; dos Remedios, C G; McKenzie, D R; Bilek, M M M

    2014-02-01

    Plasma immersion ion implantation (PIII) modifies the surface properties of polymers, enabling them to covalently immobilize proteins without using linker chemistry. We describe the use of PIII treated polycarbonate (PC) slides as a novel platform for producing microarrays of cluster of differentiation (CD) antibodies. We compare their performance to identical antibody microarrays printed on nitrocellulose-coated glass slides that are currently the industry standard. Populations of leukocytes are applied to the CD microarrays and unbound cells are removed revealing patterns of differentially immobilized cells that are detected in a simple label-free approach by scanning the slides with visible light. Intra-slide and inter-slide reproducibility, densities of bound cells, and limits of detection were determined. Compared to the nitrocellulose-coated glass slides, PIII treated PC slides have a lower background noise, better sensitivity, and comparable or better reproducibility. They require three-fold lower antibody concentrations to yield equivalent signal strength, resulting in significant reductions in production cost. The improved transparency of PIII treated PC in the near-UV and visible wavelengths combined with superior immobilization of biomolecules makes them an attractive platform for a wide range of microarray applications.

  5. Surface modification of NiTi by plasma based ion implantation for application in harsh environments

    NASA Astrophysics Data System (ADS)

    Oliveira, R. M.; Fernandes, B. B.; Carreri, F. C.; Gonçalves, J. A. N.; Ueda, M.; Silva, M. M. N. F.; Silva, M. M.; Pichon, L.; Camargo, E. N.; Otubo, J.

    2012-12-01

    The substitution of conventional components for NiTi in distinct devices such as actuators, valves, connectors, stents, orthodontic arc-wires, e.g., usually demands some kind of treatment to be performed on the surface of the alloy. A typical case is of biomaterials made of NiTi, in which the main drawback is the Ni out-diffusion, an issue that has been satisfactorily addressed by plasma based ion implantation (PBII). Even though PBII can tailor selective surface properties of diverse materials, usually, only thin modified layers are attained. When NiTi alloys are to be used in the harsh space environment, as is the case of devices designed to remotely release the solar panels and antenna arrays of satellites, e.g., superior mechanical and tribological properties are demanded. For this case the thickness of the modified layer must be larger than the one commonly achieved by conventional PBII. In this paper, new nitrogen PBII set up was used to treat samples of NiTi in moderate temperature of 450 °C, with negative voltage pulses of 7 kV/250 Hz/20 μs, in a process lasting 1 h. A rich nitrogen atomic concentration of 85 at.% was achieved on the near surface and nitrogen diffused at least for 11 μm depth. Tribological properties as well as corrosion resistance were evaluated.

  6. Binding of the cell adhesive protein tropoelastin to PTFE through plasma immersion ion implantation treatment.

    PubMed

    Bax, Daniel V; Wang, Yiwei; Li, Zhe; Maitz, Peter K M; McKenzie, David R; Bilek, Marcela M M; Weiss, Anthony S

    2011-08-01

    The interaction of proteins and cells with polymers is critical to their use in scientific and medical applications. In this study, plasma immersion ion implantation (PIII) was used to modify the surface of polytetrafluorethylene (PTFE), enabling the covalent binding of a cell adhesive protein, tropoelastin, without employing chemical linking molecules. Tropoelastin coating of untreated or PIII treated PFTE simultaneously promoted and blocked cell interactions respectively, i.e. PIII treatment of the PTFE surface completely inverses the cell interactive properties of bound tropoelastin. This activity persisted over long term storage of the PIII treated surfaces. The integrin binding C-terminus of tropoelastin was markedly less solvent exposed when bound to PIII treated PTFE than untreated PTFE, accounting for the modulation of cell adhesive activity. This presents a new methodology to specifically modulate cell behavior on a polymer surface using a simple one step treatment process, by adjusting the adhesive activity of a single extracellular matrix protein. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Tribological behavior of C-N coated spur gear by plasma source ion implantation

    NASA Astrophysics Data System (ADS)

    Lu, Long; Lyu, Sungki; He, Huibo; Cho, Sunghyun; Lee, Sanghyun

    2005-12-01

    The C-N coating can provide outstanding performance on the surface of spur gear. SCM415 specimens and test gears with steel surface were treated with carbon nitrogen by the plasma source ion implantation (PSII) method. The composition and structure of the surface layer were analyzed and compared with that of PVD coated TiN layer. It was found that both of friction coefficients of C-N coating decreased with the increase of load, however, C-N coating showed relatively lower friction coefficient than that of TiN coating. The effect of C-N coating was investigated on hardness, friction and wear. The TiN coated gear showed a more serious friction phenomenon than that of C-N coated gear. It was considered that coating of TiN, which was conducted at a vacuum chamber at about 500°C, resulted in a tempering of base material that caused microstructure change, which in turn resulted in decreasing of hardness, the C-N coated gear and pinion had higher wear resistance than that of TiN coated gear and pinion. C-N coating significantly improved the friction and wear resistance of gears.

  8. Directed cell attachment by tropoelastin on masked plasma immersion ion implantation treated PTFE.

    PubMed

    Bax, Daniel V; McKenzie, David R; Bilek, Marcela M M; Weiss, Anthony S

    2011-10-01

    The ability to generate cell patterns on polymer surfaces is critical for the detailed study of cellular biology, the fabrication of cell-based biosensors, cell separation techniques and for tissue engineering. In this study contact tape masking and steel shadow masks were used to exclude plasma immersion ion implantation (PIII) treatment from defined areas of polytetrafluoroethylene (PTFE) surfaces. This process enabled patterned covalent binding of the cell adhesive protein, tropoelastin, without employing chemical linking molecules. Tropoelastin coating rendered the untreated regions cell adhesive and the PIII-treated area non-adhesive, allowing very fine patterning of cell adhesion to PTFE surfaces. A blocking step, such as with BSA or PEG, was not required to prevent cell binding to the underlying PIII-treated regions as tropoelastin coating alone performed this blocking function. Although tropoelastin coated the entire PTFE surface, the cell binding C-terminus of tropoelastin was markedly less solvent exposed on the PIII-treated, hydrophilic regions. The differential exposure of the C-terminus correlated with the patterned distribution of tropoelastin-mediated cell adhesion. This new methodology specifically enables directed cell behavior on a polymer surface using a simple one-step treatment process, by modulating the adhesive activity of a single extracellular matrix protein.

  9. Hemocompatibility of titanium-based coatings prepared by metal plasma immersion ion implantation and deposition

    NASA Astrophysics Data System (ADS)

    Tsyganov, I. A.; Maitz, M. F.; Richter, E.; Reuther, H.; Mashina, A. I.; Rustichelli, F.

    2007-04-01

    Metal plasma immersion ion implantation and deposition (MePIIID) has been proved to be an effective approach to enhance surface properties of various types of materials. In this work structure, phase composition, microhardness and surface properties, such as wettability and surface energy of layers of the ternary system Ti-N-O produced by MePIIID were investigated. To study the correlation between structure of coating and hemocompatibility the thrombocyte adhesion as well as the fibrinogen adsorption on the surface were measured. The blood compatibility of Ti oxide can be improved by the addition of nitrogen into the layer. The thrombocyte adhesion and fibrinogen adsorption were lower for TiNxOy than for TiO2. This correlates with a lower hydrophobicity and higher polar component of the surface energy for TiNxOy. The best hemocompatibility as well as the maximal microhardness have been found for the coating TiN0.4O1.6.

  10. Growth of surface structures correlated with structural and mechanical modifications of brass by laser-induced Si plasma ions implantation

    NASA Astrophysics Data System (ADS)

    Ahmad, Shahbaz; Bashir, Shazia; Rafique, M. Shahid; Yousaf, Daniel

    2017-04-01

    Laser-produced Si plasma is employed as an ion source for implantation on the brass substrate for its surface, structural, and mechanical modifications. Thomson parabola technique is employed for the measurement of energy and flux of Si ions using CR-39. In response to stepwise increase in number of laser pulses from 3000 to 12000, four brass substrates were implanted by laser-induced Si plasma ions of energy 290 keV at different fluxes ranging from 45 × 1012 to 75 × 1015 ions/cm2. SEM analysis reveals the formation of nano/micro-sized irregular shaped cavities and pores for the various ion fluxes for varying numbers of laser pulses from 3000 to 9000. At the maximum ion flux for 12,000 pulses, distinct and organized grains with hexagonal and irregular shaped morphology are revealed. X-ray diffractometer (XRD) analysis exhibits that a new phase of CuSi (311) is identified which confirms the implantation of Si ions in brass substrate. A significant decrease in mechanical properties of implanted brass, such as Yield Stress (YS), Ultimate Tensile Strength (UTS), and hardness, with increasing laser pulses from 3000 to 6000 is observed. However, with increasing laser pulses from 9000 to a maximum value of 12,000, an increase in mechanical properties like hardness, YS, and UTS is observed. The generation as well as annihilation of defects, recrystallization, and intermixing of Si precipitates with brass matrix is considered to be responsible for variations in surface, structural, and mechanical modifications of brass.

  11. Characterization and Performance of a High-Current-Density Ion Implanter with Magnetized Hollow-Cathode Plasma Source

    NASA Astrophysics Data System (ADS)

    Falkenstein, Zoran; Rej, Donald; Gavrilov, Nikolai

    1998-10-01

    In a collaboration between the Institute of Electrophysics (IEP) and the Los Alamos National Laboratory (LANL), the IEP has developed an industrial scalable, high-power, large-area ion source for the surface modification of materials. The plasma source of the ion beam source can be described as a pulsed glow discharge with a cold, hollow-cathode in a weak magnetic field. Extraction and focusing of positive ions by an acceleration and ion-optical plate system renders the generation of a homogeneous, large-area ion beam with an averaged total ion current of up to 50 mA at acceleration voltages of up to 50 kV. The principle set-up of the ion beam source as well as some electrical characteristics (gas discharge current and the extracted ion beam current) are presented for a lab-scale prototype. Measurements of the radial ion current density profiles within the ion beam for various discharge parameters, as well as results on surface modification by ion implantation of nitrogen into aluminum and chromium are presented. Finally, a comparison of the applied ion dose with the retained ion doses is given.

  12. Initial design of a 1 megawatt average, 150 kilovolt pulse modulator for an industrial plasma source ion implantation processor

    SciTech Connect

    Reass, W.A.; Deb, D.

    1994-07-01

    Plasma Source Ion Implantation (PSII) is a materials surface modification process which can be used to improve performance characteristics of manufacturing tooling and products. Since improvements can be realized in surface hardness, reduced friction, wear, galling, and increased resistance to corrosion, PSII is applicable to a broad spectrum of manufactured items. In PSII, the object to be implanted is placed in a weakly ionized plasma and pulsed to a high negative voltage. The plasma ions are accelerated into the object`s surface, thereby changing its` chemical and physical composition. The plasma dynamic load impedance is highly variable, dependent on implant object area, plasma density, and material composition. The modulator load impedance may be a few tens of ohms and a few thousand picofarads early in time. Late in time, the load may appear as 20,000 Ohms and 100 picofarads. The modulator system must accommodate any process changes, in addition to (frequent) initial ``start-up`` object arcs (from impurities). To implant the required ion densities in a minimum of time, multi-kilohertz rep-rates are often required. An evolutionary design approach was utilized to design a cost-effective and reliable modulator system with components of established performance, suitable for a manufacturing environment. This paper, in addition to presenting the anticipated modulator design required for the PSII application, will review similar modulator topologies and determine operational lifetime characteristics. Further improvements in system electrical efficiency can also be realized with incremental design modifications to the high voltage switch tubes. Development options for upgraded switch tubes of higher efficiency will also be presented.

  13. Enhanced retained dose uniformity in NiTi spinal correction rod treated by three-dimensional mesh-assisted nitrogen plasma immersion ion implantation

    SciTech Connect

    Lu, Q. Y.; Hu, T.; Kwok, Dixon T. K.; Chu, Paul K.

    2010-05-15

    Owing to the nonconformal plasma sheath in plasma immersion ion implantation of a rod sample, the retained dose can vary significantly. The authors propose to improve the implant uniformity by introducing a metal mesh. The depth profiles obtained with and without the mesh are compared and the implantation temperature at various locations is evaluated indirectly by differential scanning calorimeter. Our results reveal that by using the metal mesh, the retained dose uniformity along the length is greatly improved and the effects of the implantation temperature on the localized mechanical properties of the implanted NiTi shape memory alloy rod are nearly negligible.

  14. The influence of repetitively pulsed plasma immersion low energy ion implantation on TiN coating formation and properties

    NASA Astrophysics Data System (ADS)

    Sivin, D. O.; Ananin, P. S.; Dektyarev, S. V.; Ryabchikov, A. I.; Shevelev, A. E.

    2017-05-01

    Application of high frequency short pulse plasma immersion low energy ion implantation for titanium nitride coating deposition using vacuum arc metal plasma and hot-cathode gas-discharge plasma on R6M5 alloy was investigated. Implementation of negative repetitively pulsed bias with bias amplitude 2 kV, pulse duration 5 μs and pulse frequency 105 Hz leads to 6.2-fold decrease of vacuum arc macroparticle surface density for macroparticles with diameter less than 0.5 μm. Ion sputtering due coating deposition reduces the production rate approximately by 30%. It was found that with bias amplitude range from 1.1 to 1.4 kV and pulse duration 5 μs yields to formation of coatings with local hardness up to 40 GPa. This paper presents the results of experimental studies of adhesion strength, tribological properties and surface morphology of deposited TiN coatings.

  15. Pulsed source ion implantation apparatus and method

    DOEpatents

    Leung, Ka-Ngo

    1996-01-01

    A new pulsed plasma-immersion ion-implantation apparatus that implants ions in large irregularly shaped objects to controllable depth without overheating the target, minimizing voltage breakdown, and using a constant electrical bias applied to the target. Instead of pulsing the voltage applied to the target, the plasma source, for example a tungsten filament or a RF antenna, is pulsed. Both electrically conducting and insulating targets can be implanted.

  16. Pulsed source ion implantation apparatus and method

    DOEpatents

    Leung, K.N.

    1996-09-24

    A new pulsed plasma-immersion ion-implantation apparatus that implants ions in large irregularly shaped objects to controllable depth without overheating the target, minimizing voltage breakdown, and using a constant electrical bias applied to the target. Instead of pulsing the voltage applied to the target, the plasma source, for example a tungsten filament or a RF antenna, is pulsed. Both electrically conducting and insulating targets can be implanted. 16 figs.

  17. Tailored SERS substrates obtained with cathodic arc plasma ion implantation of gold nanoparticles into a polymer matrix.

    PubMed

    Ferreira, Jacqueline; Teixeira, Fernanda S; Zanatta, Antonio R; Salvadori, Maria C; Gordon, Reuven; Oliveira, Osvaldo N

    2012-02-14

    This manuscript reports on the fabrication of plasmonic substrates using cathodic arc plasma ion implantation, in addition to their performance as SERS substrates. The technique allows for the incorporation of a wide layer of metallic nanoparticles into a polymer matrix, such as PMMA. The ability to pattern different structures using the PMMA matrix is one of the main advantages of the fabrication method. This opens up new possibilities for obtaining tailored substrates with enhanced performance for SERS and other surface-enhanced spectroscopies, as well as for exploring the basic physics of patterned metal nanostructures. The architecture of the SERS-active substrate was varied using three adsorption strategies for incorporating a laser dye (rhodamine): alongside the nanoparticles into the polymer matrix, during the polymer cure and within nanoholes lithographed on the polymer. As a proof-of-concept, we obtained the SERS spectra of rhodamine for the three types of substrates. The hypothesis of incorporation of rhodamine molecules into the polymer matrix during the cathodic arc plasma ion implantation was supported by FDTD (Finite-Difference Time-Domain) simulations. In the case of arrays of nanoholes, rhodamine molecules could be adsorbed directly on the gold surface, then yielding a well-resolved SERS spectrum for a small amount of analyte owing to the short-range interactions and the large longitudinal field component inside the nanoholes. The results shown here demonstrate that the approach based on ion implantation can be adapted to produce reproducible tailored substrates for SERS and other surface-enhanced spectroscopies.

  18. Structural phase states in nickel-titanium surface layers doped with silicon by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Kashin, Oleg A.; Lotkov, Aleksandr I.; Kudryashov, Andrey N.; Krukovsky, Konstantin V.; Ostapenko, Marina G.; Neiman, Alexey A.; Borisov, Dmitry P.

    2015-10-01

    The paper reports on a study of NiTi-based alloys used for manufacturing self-expanding intravascular stents to elucidate how the technological modes of plasma immersion ion implantation with silicon influence the chemical and phase composition of their surface layers. It is shown that two types of surface structure can be obtained depending on the mode of plasma immersion implantation: quasi-amorphous Si coating and Si-doped surface layer. The Si-doped surface layer contains new phases: a phase structured as the main B2 phase of NiTi but with a lower lattice parameter, R phase, and phase of highly dispersed SiO2 precipitates.

  19. Study of the effects of E × B fields as mechanism to carbon-nitrogen plasma immersion ion implantation on stainless steel samples

    NASA Astrophysics Data System (ADS)

    Pillaca, E. J. D. M.; Ueda, M.; Oliveira, R. M.; Pichon, L.

    2014-08-01

    Effects of E × B fields as mechanism to carbon-nitrogen plasma immersion ion implantation (PIII) have been investigated. This magnetic configuration when used in PIII allows obtaining high nitrogen plasma density close to the ion implantation region. Consequently, high ions dose on the target is possible to be achieved compared with standard PIII. In this scenario, nitrogen and carbon ions were implanted simultaneously on stainless steel, as measured by GDOES and detected by X-ray diffraction. Carbon-tape disposed on the sample-holder was sputtered by intense bombardment of nitrogen ions, being the source of carbon atoms in this experiment. The implantation of both N and C caused changes on sample morphology and improvement of the tribological properties of the stainless steel.

  20. Boron Profile Sharpening in Ultra-Shallow p{sup +}-n Junction Produced by Plasma Immersion Ion Implantation from BF{sub 3} Plasma

    SciTech Connect

    Lukichev, V.; Rudenko, K.; Orlikovsky, A.; Pustovit, A.; Vyatkin, A.

    2008-11-03

    We have investigated plasma immersion ion implantation (PI{sup 3}) of boron with energies of 500 eV (doses up to 2x10{sup 15} cm{sup -2}) from BF{sub 3} plasma with He pre-amorphizing implantation (PAI)(energy 3 keV, dose 5x10{sup 16} cm{sup -2}). Implanted samples were subjected to RTA (T = 900 to 1050 deg. C, t = 2 to 24 sec and spike anneal). SIMS analysis of boron profiles revealed its anomalous behavior. For short RTA times the profile tail (below 5x10{sup 19} cm{sup -3}) moves toward the surface and then, as in the usual diffusion, toward the bulk at longer annealing times.

  1. The structure and tribological properties of gradient layers prepared by plasma-based ion implantation on 2024 Al alloy

    NASA Astrophysics Data System (ADS)

    Liao, J. X.; Xia, L. F.; Sun, M. R.; Liu, W. M.; Xu, T.; Xue, Q. J.

    2004-02-01

    Using plasma-based ion implantation, two types of gradient layers have been prepared on 2024 Al alloy. One is prepared by N-implantation then C-deposition, the other adds an interlayer composed of a Ti layer and a Ti-N layer between N-implantation and C-deposition. C-deposition is carried out at various implanting voltages or C2H2/H2 ratios. The composition depth profiles of these layers were characterized by x-ray photoelectron spectroscopy. The structure, morphologies and microstructure of the C layers were studied using Raman spectroscopy, atomic force microscope and transmission electron microscope, respectively. The surface hardness was measured with a Knoop tester and a mechanical property microprobe. The dry ball-on-disc wear tests were performed in ambient air. The gradient layer without interlayer is composed of an N-implanted layer rich in AlN and a diamond-like carbon (DLC) layer (film), and the two layers are connected with a C-Al transition layer containing Al4C3. The Ti layer rich in agr -Ti and the N-implanted layer are connected by a Ti-Al transition layer containing TiAl3, while the Ti-N layer rich in TiN and the DLC film are connected by a C-Ti transition layer containing TiC, TiCN, etc. Thus, the gradient layer with interlayers has optimized the gradient structure. DLC films are compact and amorphous, contain high sp3/sp2 ratios and depend on the implanting voltage and the C2H2/H2 ratio. Similarly, these gradient layers exhibit significant improvement in morphologies, surface hardness and tribological properties; the interlayer, the implanting voltage and the C2H2/H2 ratio all have prominent effects on these properties.

  2. Controlled fabrication of Si nanocrystal delta-layers in thin SiO{sub 2} layers by plasma immersion ion implantation for nonvolatile memories

    SciTech Connect

    Bonafos, C.; Ben-Assayag, G.; Groenen, J.; Carrada, M.; Spiegel, Y.; Torregrosa, F.; Normand, P.; Dimitrakis, P.; Kapetanakis, E.; Sahu, B. S.; Slaoui, A.

    2013-12-16

    Plasma Immersion Ion Implantation (PIII) is a promising alternative to beam line implantation to produce a single layer of nanocrystals (NCs) in the gate insulator of metal-oxide semiconductor devices. We report herein the fabrication of two-dimensional Si-NCs arrays in thin SiO{sub 2} films using PIII and rapid thermal annealing. The effect of plasma and implantation conditions on the structural properties of the NC layers is examined by transmission electron microscopy. A fine tuning of the NCs characteristics is possible by optimizing the oxide thickness, implantation energy, and dose. Electrical characterization revealed that the PIII-produced-Si NC structures are appealing for nonvolatile memories.

  3. dc field-emission analysis of GaAs and plasma-source ion-implanted stainless steel

    SciTech Connect

    C. Hernandez; T. Wang; T. Siggins; D. Bullard; H. F. Dylla; C. Reece; N. D. Theodore; D. M. Manos

    2003-06-01

    Field-emission studies have been performed on a GaAs wafer and a sample of its stainless-steel (SS) support electrode that are part of a photocathode gun for the 10 kW Upgrade infrared free electron laser at Jefferson Lab. The objective of the studies presented here is to characterize the effect of both the cleanliness of the wafer and the plasma-source ion-implanted layer on the electrode to suppress field emission. Field emission is the limiting factor to achieve the required 6 MV/m at the surface of the wafer. Potential field emitters are first located on the surface of 1 in. diameter samples with a dc scanning field-emission microscope at 60 MV/m, then each emitter is characterized in a scanning electron microscope equipped with an energy dispersive spectrometer. The GaAs wafer was hydrogen cleaned before the study. The results show three emitters caused by indium contamination during wafer handling. The GaAs wafer thus shows good high-voltage characteristics and the need to maintain cleanliness during handling. The SS sample is hand polished with diamond paste to a 1-m surface finish, then implanted with N2/SiO2 in a plasma-source ion-implantation chamber in preparation for the field-emission studies.

  4. Effect of oxygen plasma immersion ion implantation treatment on corrosion resistance and cell adhesion of titanium surface.

    PubMed

    Yang, Chih-Hsiung; Wang, Yu-Tsai; Tsai, Wen-Fa; Ai, Chi-Fong; Lin, Mau-Chin; Huang, Her-Hsiung

    2011-12-01

    The study was to investigate the corrosion resistance and cell adhesion of titanium (Ti) surface for dental implant application by oxygen plasma immersion ion implantation (O-PIII) treatments. Commercially pure Ti discs (grade 2) were used as the substrate. O-PIII surface treatments, with different oxygen doses (1 × 10(16) and 4 × 10(16) ions/cm(2)), were performed in a high-vacuum chamber with a radio frequency plasma source. Atomic force microscope, X-ray photoelectron spectrometer and nanoindenter were used to analyze surface topography, chemical composition (three samples per group) and mechanical property (twenty-five samples per group) of Ti specimens, respectively. Corrosion resistance of Ti specimens (five samples per group) was evaluated by potentiodynamic polarization curve measurement in simulated blood plasma solution. The adhesion and spreading of human bone marrow mesenchymal stem cells (hMSCs) on Ti surfaces were studied. The results showed that O-PIII treatment had no significant influence on the surface topography of Ti specimens. The thickness of oxide layer (mainly as TiO(2)) on the O-PIII-treated Ti specimens increased with an increase in oxygen dose implanted. The O-PIII-treated Ti specimens possessed higher surface hardness and Young's modulus than the untreated Ti specimen. Potentiodynamic polarization tests revealed that the O-PIII-treated Ti surfaces had lower corrosion rate (I(corr)) and passive current (I(pass)) than the untreated Ti surface. The adhesion and spreading of hMSCs on Ti surfaces were improved by O-PIII treatment. O-PIII treatment could enhance the corrosion resistance and cell adhesion of Ti surface for dental implant application due to the increase in surface thickness of Ti-oxides (mainly as TiO(2)) on Ti. © 2011 John Wiley & Sons A/S.

  5. Dispersion and absorption of longitudinal electro-kinetic wave in ion-implanted GaN semiconductor plasmas

    SciTech Connect

    Soni, Dilip; Sharma, Giriraj; Saxena, Ajay; Jadhav, Akhilesh

    2015-07-31

    An analytical study on propagation characteristics of longitudinal electro-kinetic (LEK) waves is presented. Based on multi-fluid model of plasma, we have derived a dispersion relation for LEK waves in colloid laden GaN semiconductor plasmas. It is assumed that ions are implanted to form colloids in the GaN sample. The colloids are continuously bombarded by the plasma particles and stick on them, but they acquire a net negative charge due to relatively higher mobility of electrons. It is found from the dispersion relation that the presence of charged colloids not only modifies the existing modes but also supports new novel modes of LEKWs. It is hoped that the study would enhance understanding on dispersion and absorption of LEKWs and help in singling out the appropriate configurations in which GaN crystal would be better suited for fabrication of microwave devices.

  6. Revealing the surface origin of green band emission from ZnO nanostructures by plasma immersion ion implantation induced quenching

    SciTech Connect

    Yang, Y.; Sun, X. W.; Tay, B. K.; Cao, Peter H. T.; Wang, J. X.; Zhang, X. H.

    2008-03-15

    Surface defect passivation for ZnO nanocombs (NCBs), random nanowires (RNWs), and aligned nanowires (ANWs) was performed through a metal plasma immersion ion implantation with low bias voltages ranging from 0 to 10 kV, where Ni was used as the modification ion. The depth of surface-originated green band (GB) emission is thus probed, revealing the surface origin of the GB. It is also found that the GB is closely related to oxygen gas content during growth of the nanostructures. The GB origin of NCBs and RNWs grown with higher oxygen content is shallower ({approx}0.5 nm), which can be completely quenched with no bias applied. However, the GB origin of ANWs grown at lower oxygen content is much deeper ({approx}7 nm) with a complete quenching bias of 10 kV. Quenching of the GB can be attributed to passivation of the surface hole or electron trapping sites (oxygen vacancies) by Ni ions.

  7. Cell adhesion and growth on surfaces modified by plasma and ion implantation

    NASA Astrophysics Data System (ADS)

    Araujo, W. W. R.; Teixeira, F. S.; da Silva, G. N.; Salvadori, D. M. F.; Salvadori, M. C.

    2014-04-01

    In this study, we show and discuss the results of the interaction of living CHO (Chinese Hamster Ovary) cells, in terms of adhesion and growth on glass, SU-8 (epoxi photoresist), PDMS (polydimethylsiloxane), and DLC (hydrogen free diamond-like carbon) surfaces. Glass, SU-8, and DLC but not PDMS showed to be good surfaces for cell growth. DLC surfaces were treated by oxygen plasma (DLC-O) and sulfur hexafluoride plasma (DLC-F). After 24 h of cell culture, the number of cells on DLC-O was higher than on DLC-F surface. SU-8 with silver implanted, creating nanoparticles 12 nm below the surface, increased significantly the number of cells per unit area.

  8. Plasma immersion ion implantation: A viable candidate for low cost purification of mc-Si by nanocavities?

    NASA Astrophysics Data System (ADS)

    Kouadri-boudjelthia, E.-A.; Ntsoenzok, E.; Benoit, R.; Regula, G.; Etienne, H.; Michel, T.; Ashok, S.

    2016-01-01

    A low-cost purification technique was evaluated on multicrystalline silicon (mc-Si). It consists of an efficient impurity trapping process involving nanocavities created by plasma immersion ion implantation (PIII). The study consisted of assessing (i) the creation of nanocavities by PIII and (ii) their ability to trap impurities in real conditions (without intentional contamination). Square pieces of p-type mc-Si samples, having a surface of 4 cm2 were used. They were implanted with hydrogen by PIII at 20 kV with a fluence of 5 × 1016 cm-2 and then annealed for 30 min, in the temperature range 673-1273 K. The evolution of shape, size and spatial distribution of nanocavities was studied by transmission electron microscopy and time of flight secondary ion mass spectrometry in order to check both the formation of cavities and to test their ability to getter impurities by either precipitation or chemisorption. Results reveal surprisingly that, despite the triangular as-implanted H profile, nanocavities can be created by H-PIII, evidently because of the multi-energetic and high flux implantation (about 8 × 1013 cm-2 s-1, 40-80 times greater than in conventional implantation) and that they are able to trap various impurities, initially present in mc-Si, such as Fe, Cu and Ni (according to their Gibbs energy), competing with the many existing gettering sites available in mc-Si, such as Si-related precipitates (oxygen, carbon, nitrogen or metal silicides), dislocations and grain boundaries. The area containing the biggest cavities have the highest density of gettering sites, especially for Cu, which can be trapped either by chemisorption (since it has higher binding energy with cavities) or by Cu3Si precipitation since the corresponding volume expansion can be damped by surrounding cavities.

  9. Blood compatibility of titanium-based coatings prepared by metal plasma immersion ion implantation and deposition

    NASA Astrophysics Data System (ADS)

    Tsyganov, I.; Maitz, M. F.; Wieser, E.

    2004-07-01

    Titanium with its natural oxide is known to be generally good biocompatible; and therefore, the suitability of some Ti-based coatings as coating for blood-contacting implants is analyzed. Layers of pure Ti, Ti oxynitrides (TiN 1- xO x with x=0.25, 0.50, and 0.75), and Ti oxides were deposited on oxidized Si from a plasma produced by cathodic arc evaporation under addition of N 2 and/or O 2 to the ambient near the substrate. The oxynitrides are crystalline with the fcc structure of TiN up to x=0.25. For x=0.5, a two-phase system of fcc TiN and fcc TiO has been found. In dependence on the deposition parameters, amorphous and crystalline layers (anatase + brookite or rutile) of TiO 2 have been obtained. The rutile layers were doped by implantation of P. The amorphous TiO 2 layers were implanted with Cr. To study the correlation between structure of the coating and blood compatibility, the clotting time of blood plasma as well as the adhesion and activation of blood platelets on the surface was investigated. TiN and oxynitrides showed the longest clotting time compared to rutile. Minimum platelet adhesion has been observed for pure TiO 2. Contrasting tendencies in the dependence of clotting time and platelet adhesion on the microstructure have been stated. However, for P +-doped rutile, both enhanced clotting time and improved platelet adhesion were observed. Platelet adherence and activation always showed similar trends.

  10. Effects of carbon and nitrogen plasma immersion ion implantation on in vitro and in vivo biocompatibility of titanium alloy.

    PubMed

    Zhao, Ying; Wong, Sze Man; Wong, Hoi Man; Wu, Shuilin; Hu, Tao; Yeung, Kelvin W K; Chu, Paul K

    2013-02-01

    Growth of bony tissues on titanium biomedical implants can be time-consuming, thereby prolonging recovery and hospitalization after surgery and a method to improve and expedite tissue-implant integration and healing is thus of scientific and clinical interests. In this work, nitrogen and carbon plasma immersion ion implantation (N-PIII and C-PIII) is conducted to modify Ti-6Al-4V to produce a graded surface layer composed of TiN and TiC, respectively. Both PIII processes do not significantly alter the surface hydrophilicity but increase the surface roughness and corrosion resistance. In vitro studies disclose improved cell adhesion and proliferation of MC3T3-E1 preosteoblasts and L929 fibroblasts after PIII. Micro-CT evaluation conducted 1 to 12 weeks after surgery reveals larger average bone volumes and less bone resorption on the N-PIII and C-PIII titanium alloy pins than the unimplanted one at every time point. The enhancements observed from both the in vitro and in vivo studies can be attributed to the good cytocompatibility, roughness, and corrosion resistance of the TiN and TiC structures which stimulate the response of preosteoblasts and fibroblasts and induce early bone formation. Comparing the two PIII processes, N-PIII is more effective and our results suggest a simple and practical means to improve the surface biocompatibility of medical-grade titanium alloy implants.

  11. Improving the corrosion resistance of nitinol by plasma-immersion ion implantation with silicon for biomedical applications

    NASA Astrophysics Data System (ADS)

    Abramova, P. V.; Korshunov, A. V.; Lotkov, A. I.; Kashin, O. A.; Borisov, D. P.

    2015-11-01

    Cyclic voltammetry and potentiostatic polarization have been applied to study electrochemical behavior and to determine corrosion resistance of nitinol, which surface was modified with silicon using plasma-immersion ion implantation, in 0.9 % NaCl solution and in artificial blood plasma. It was found out that continuous, and also homogeneous in composition thin Si-containing layers are resistant to corrosion damage at high positive potentials in artificial physiological solutions due to formation of stable passive films. Breakdown potential Eb of Si-modified NiTi depends on the character of silicon and Ni distribution at the alloy surface, Eb values amounted to 0.9-1.5 V (Ag/AgCl/KCl sat.) for the alloy samples with continuous Si-containing surface layers and with decreased Ni surface concentration.

  12. Passivation layer on polyimide deposited by combined plasma immersion ion implantation and deposition and cathodic vacuum arc technique

    SciTech Connect

    Han, Z. J.; Tay, B. K.; Sze, J. Y.; Ha, P. C. T.

    2007-05-15

    A thin passivation layer of aluminum oxide was deposited on polyimide by using the combined plasma immersion ion implantation and deposition (PIII and D) and cathodic vacuum arc technique. X-ray photoelectron spectroscopy C 1s spectra showed that the carbonyl bond (C=O) and ether group (C-O-C and C-N-C) presented in pristine polyimide were damaged by implantation of aluminum ions and deposition of an aluminum oxide passivation layer. O 1s and Al 2p spectra confirmed the formation of a thin aluminum oxide passivation layer. This passivation layer can be implemented in aerospace engineering where polyimide may suffer degradation from fast atomic oxygen in the low-earth-orbit environment. To test the protection of this passivation layer to energetic oxygen ions, a plasma-enhanced chemical vapor deposition system was used to simulate the oxygen-ion irradiation, and the results showed that a higher weight occurred for passivated samples compared to pristine ones. X-ray diffraction showed that Al peaks were presented on the surface region, but no aluminum oxide peak was detected. The authors then concluded that Al clusters were formed in polyimide besides aluminum oxide, which was in an x-ray amorphous state. Furthermore, contact-angle measurements showed a reduced contact angle for passivated polyimide from a pristine value of 78 deg. to 20 deg. by using deionized water. Several discussions have been made on the surface chemical and structural property changes by using the combined PIII and D and cathodic vacuum arc technique.

  13. DLC coating of interior surfaces of steel tubes by low energy plasma source ion implantation and deposition

    NASA Astrophysics Data System (ADS)

    Baba, K.; Hatada, R.; Flege, S.; Ensinger, W.

    2014-08-01

    The plasma source ion implantation (PSII) process can be used for the treatment of the interior surfaces of tubes. Typically, this is done with higher ion energies of 10 keV or more. The resulting film thickness and the properties of the DLC film usually show a dependence on position, i.e. the distance from the edge of the tube. In order to investigate whether this effect is also present with lower energies (and if so, to what extent), deposition was carried out at negative pulse voltages of -5 kV. A diamond-like carbon (DLC) film was deposited by using acetylene as the plasma gas. The substrate consisted of stainless steel tubes with an inner diameter of 20 mm and a length of 100 and 200 mm, respectively. The distribution of the thickness, film composition, structure, surface morphology and friction coefficient as a function of the position inside the tube were investigated. The results of this low energy treatment were compared with investigations which employed higher ion energies.

  14. Oxygen plasma immersion ion implantation treatment enhances the human bone marrow mesenchymal stem cells responses to titanium surface for dental implant application.

    PubMed

    Yang, Chih-Hsiung; Li, Yu-Chen; Tsai, Wen-Fa; Ai, Chi-Fong; Huang, Her-Hsiung

    2015-02-01

    The present investigation utilized a novel oxygen plasma immersion ion implantation (O-PIII) treatment to create a dense and thin oxide layer on a titanium (Ti) surface for dental implant application. This study evaluated the behavior of human bone marrow mesenchymal stem cells (hMSCs) on O-PIII-treated Ti. The O-PIII treatments were performed using different oxygen ion doses (T(L): 1 × 10(16); T(M): 4 × 10(16); T(H): 1 × 10(17) ions/cm(2)). Analysis using an X-ray photoelectron spectrometer (XPS) and high resolution X-ray diffractometer (HR-XRD) indicated that the O-PIII-treated specimen T(M) had the highest proportion of rutile phase TiO2 component. The O-PIII-treated specimen T(M) had the greatest protein adsorption capability of the test Ti surfaces using XPS analysis and bicinchoninic acid (BCA) protein assay. Immunofluorescent staining revealed that hMSCs had the best cell adhesion on the O-PIII-treated specimen T(M), whereas green fluorescent protein (GFP)-labeled hMSCs experienced the fastest cell migration based on a wound healing assay. Other assays, including MTT assay, Alizarin red S staining and Western blot analysis, demonstrated that the adhered hMSCs exhibited the greatest cell proliferation, mineralization, and differentiation capabilities on the TM specimen. Oxidated Ti (primarily rutile TiO2 ) was produced using a facile and rapid O-PIII treatment procedure, which enhances the biocompatibility of the Ti surface with potential implications for further dental implant application. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Investigation of plasma immersion ion implantation of nickel-titanium rod by multiple-grid particle-in-cell simulation

    SciTech Connect

    Kwok, Dixon T. K.; Wu, Shuilin; Liu, Xiangmei; Fu, Ricky K. Y.; Chu, Paul K.

    2008-03-01

    A multiple-grid-particle-in-cell numerical method has been developed. This method uses grids of different cell sizes and details are needed in only one part of the simulation region and not others. Hence, there are fewer nodes in the simulation thereby reduced computational time without sacrificing details. In the multiple-grid system, a phenomenon is identified to arise at the interface between two grids and a half-cell weighting method is utilized to solve the weighting issue at the boundary. It is shown that the expression of the change of momentum has no weighting function. This method is employed to numerically simulate the plasma immersion ion implantation process into a nickel titanium rod measuring 50 mm long and 4.8 mm in diameter used in orthopaedic surgery. To conduct more uniform implantation, the NiTi rod is elevated on the sample stage by a metal rod. The nitrogen implantation fluences and depth profiles are simulated and compared to experimental values determined by x-ray photoelectron spectroscopy.

  16. Improvement of the corrosion property of Cr4Mo4V bearing steel using plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Wang, S. Y.; Chu, P. K.; Tang, B. Y.; Zeng, X. C.; Wang, X. F.

    1997-05-01

    The working conditions of aerospace bearings such as engine bearings are quite harsh and prolonging the life span of these components is thus very important to the aerospace industry. Previous results have shown that the main failure mechanism of aerospace bearings is corrosion, and enhancing their corrosion resistance is a key. Cr4Mo4V, which is equivalent to AISI M50 bearing steel, is usually used in aerospace bearings in China. In this study, Cr4Mo4V components are treated in a new generation plasma immersion ion implanter in which ion implantation and sputter deposition can be carried out in the same chamber without breaking vacuum. Three treatment processes involving Cr, Mo, and N are evaluated. Our test results indicate that Cr is the main element enhancing the corrosion resistance and the addition of nitrogen improves the properties further. The non line-of-sight advantage of PIII is important to the processing of complex-shaped samples such as engine bearings.

  17. Plasma immersion ion implantation on 15-5PH stainless steel: influence on fatigue strength and wear resistance

    NASA Astrophysics Data System (ADS)

    Bonora, R.; Cioffi, M. O. H.; Voorwald, H. J. C.

    2017-05-01

    Surface improvement in steels is of great interest for applications in industry. The aim of this investigation is to study the effect of nitrogen ion implantation on the axial fatigue strength and wear resistance of 15-5 PH stainless steel. It is well know that electroplated coatings, which are used to improve abrasive wear and corrosion properties, affects negatively the fatigue strength. It is also important to consider requirements to reduce the use of coated materials with electroplated chromium and cadmium, that produce waste, which is harmful to health and environment. The HVOF (High velocity oxygen fuel) process provides hardness, wear strength and higher fatigue resistance in comparison to electroplated chromium. Plasma immersion ion implantation has been used to enhance the hardness, wear, fatigue and corrosion properties of metals and alloys. In the present research the fatigue life increased twice for 15-5 PH three hours PIII treated in comparison to base material. From the abrasive wear tests a lower pin mass reduction was observed, associated to the superficial treatments. The improvement of fatigue and mechanical performance is attributed to a combination of nitrides phase structure and compressive residual stresses during the PIII treatment.

  18. Phase formation and mechanical/tribological modification induced by nitrogen high temperature plasma based ion implantation into molybdenum

    NASA Astrophysics Data System (ADS)

    Carreri, F. C.; Oliveira, R. M.; Oliveira, A. C.; Silva, M. M. N. F.; Ueda, M.; Silva, M. M.; Pichon, L.

    2014-08-01

    Transition metal nitrides present high hardness, good wear resistance and chemical stability. The formation of a surface layer of these materials on different types of substrates can improve surface properties without changing bulk characteristics. Molybdenum is used in many technological applications and the search for ways to effectively improve its properties is justified. In this work nitrogen ions were implanted into molybdenum by means of high temperature plasma based ion implantation (HTPBII), in order to produce a layer of molybdenum nitride on the surface of the material. The treatment was performed in the temperature range of 800-1200 °C, for 1 h. X-ray diffraction spectra showed the presence of the cubic-Mo2N phase in most of the samples. The tetragonal-Mo2N phase was also observed, depending on treatment conditions. Glow discharge optical emission spectroscopy was used to study the composition and thickness of the nitride layer. A 12 μm thick Mo2N layer was observed for samples treated at 1100 °C, although beyond this temperature threshold, a significant amount of nitride can no longer be produced. In relation to the surface mechanical properties, a ninefold increase in surface hardness was obtained, as well as a decrease in the friction coefficient. Wear against an alumina ball was not observed.

  19. Diffusion, trapping, and isotope exchange of plasma implanted deuterium in ion beam damaged tungsten

    NASA Astrophysics Data System (ADS)

    Barton, Joseph Lincoln

    Tritium accumulation in nuclear fusion reactor materials is a major concern for practical and safe fusion energy. This work examines hydrogen isotope exchange as a tritium removal technique, analyzes the effects of neutron damage using high energy copper ion beams, and introduces a diffusion coefficient that is a function of the concentration of trapped atoms. Tungsten samples were irradiated with high energy (0.5 - 5 MeV) copper ions for controlled levels of damage - 10-3 to 10-1 displacements per atom (dpa) - at room temperature. Samples were then exposed to deuterium plasma at constant temperature (˜ 380 K) to a high fluence of 1024 ions/m2, where retention is at is maximized (i.e. saturated). By then subsequently exposing these samples to fractions of this fluence with hydrogen plasma, isotope exchange rates were observed. The resulting deuterium still trapped in the tungsten is then measured post mortem. Nuclear reaction analysis (NRA) gives the depth resolved deuterium retention profile with the 3He(D,p) 4He reaction, and thermal desorption spectroscopy (TDS) gives the total amount of deuterium trapped in the tungsten by heating a sample in vacuum up to 1200 K and measuring the evaporated gas molecules with a residual gas analyzer. Isotope exchange data show that hydrogen atoms can displace trapped deuterium atoms efficiently only up to the first few microns, but does not affect the atoms trapped at greater depths. In ion damaged tungsten, measurements showed a significant increase in retention in the damage region proportional to dpa 0.66, which results in a significant spike in total retention, and isotope exchange in damaged samples is still ineffective at depths greater than a few microns. Thus, isotope exchange is not an affective tritium removal technique; however, these experiments have shown that trapping in material defects greatly affects diffusion. These experiments lead to a simplified diffusion model with defect densities as the only free

  20. Haemocompatibility of hydrogenated amorphous carbon (a-C:H) films synthesized by plasma immersion ion implantation-deposition

    NASA Astrophysics Data System (ADS)

    Yang, P.; Kwok, S. C. H.; Chu, P. K.; Leng, Y. X.; Chen, J. Y.; Wang, J.; Huang, N.

    2003-05-01

    Diamond-like-carbon has attracted much attention recently as a potential biomaterial in blood contacting biomedical devices. However, previous reports in this area have not adequately addressed the biocompatibility and acceptability of the materials in blood contacting applications. In this study, hydrogenated amorphous carbon (a-C:H) films were fabricated on silicon wafers (1 0 0) using plasma immersion ion implantation-deposition. A series of a-C:H films with different structures and chemical bonds were fabricated under different substrate voltages. The results indicate that film graphitization is promoted at higher substrate bias. The film deposited at a lower substrate bias of -75 V possesses better blood compatibility than the films at higher bias and stainless steel. Our results suggest two possible paths to improve the blood compatibility, suppression of the endogenic clotting system and reduction of platelet activation.

  1. Tunable transport properties of n-type ZnO nanowires by Ti plasma immersion ion implantation

    SciTech Connect

    Liao, L.; Zhang, Z.; Yan, B.; Li, G. P.; Wu, T.; Shen, Z. X.; Yu, T.; Yang, Y.; Cao, H. T.; Chen, L. L.; Tay, B. K.; Sun, X. W.

    2008-10-01

    Single-crystalline, transparent conducting ZnO nanowires were obtained simply by Ti plasma immersion ion implantation (PIII). Electrical transport characterizations demonstrate that the n-type conduction of ZnO nanowire could be tuned by appropriate Ti-PIII. When the energy of PIII is increased, the resistivity of ZnO decreases from 4x10{sup 2} to 3.3x10{sup -3} {omega} cm, indicating a semiconductor-metal transition. The failure-current densities of the metallic ZnO could be up to 2.75x10{sup 7} A/cm{sup 2}. Therefore, this facile method may provide an inexpensive alternative to tin doped indium oxide as transparent conducting oxide materials.

  2. Current transport studies of ZnO /p-Si heterostructures grown by plasma immersion ion implantation and deposition

    NASA Astrophysics Data System (ADS)

    Chen, X. D.; Ling, C. C.; Fung, S.; Beling, C. D.; Mei, Y. F.; Fu, Ricky K. Y.; Siu, G. G.; Chu, Paul. K.

    2006-03-01

    Rectifying undoped and nitrogen-doped ZnO /p-Si heterojunctions were fabricated by plasma immersion ion implantation and deposition. The undoped and nitrogen-doped ZnO films were n type (n˜1019cm-3) and highly resistive (resistivity ˜105Ωcm), respectively. While forward biasing the undoped-ZnO /p-Si, the current follows Ohmic behavior if the applied bias Vforward is larger than ˜0.4V. However, for the nitrogen-doped-ZnO /p-Si sample, the current is Ohmic for Vforward<1.0V and then transits to J ˜V2 for Vforward>2.5V. The transport properties of the undoped-ZnO /p-Si and the N-doped-ZnO /p-Si diodes were explained in terms of the Anderson model and the space charge limited current model, respectively.

  3. Effects of oxygen plasma source ion implantation on microstructure evolution and mechanical properties of nickel-titanium shape memory alloy

    NASA Astrophysics Data System (ADS)

    Tan, Lizhen

    Near-equiatomic NiTi is an important shape memory alloy used in both medical and non-medical applications, which are dependent upon the surface characteristics of NiTi. The work presented here is the first use of plasma source ion implantation with oxygen as the incident species to modify the surface structure of NiTi shape memory alloy. Two levels of voltage bias and three levels of ion dose were employed to investigate the effect of processing parameters on surface microstructure and surface-related properties. Several surface analytical techniques, Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM), were employed to analyze the effects of the surface modification on surface characteristics including oxide thickness, oxide constitution, phase distribution, morphology and topography. A two-layer surface structure consisting of an oxide layer and a precipitate accommodation layer was observed on modified NiTi. The surface morphology, roughness and hydrophilicity, which are considered to play important roles in affecting protein adsorption behavior, were found to be altered by surface modification. The effects of surface modification on surface-related properties including corrosion resistance, hardness and wear resistance were evaluated by cyclic potentiodynamic polarization tests, Knoop hardness microindentation and fretting wear tests, respectively. The optimum corrosion and wear resistance of NiTi were achieved with ion implantation under high bias and moderate dose. Archard's equation was modified by incorporating the pseudoelasticity effect on wear resistance in addition to hardness. The modified Archard's equation better describes the fretting wear resistance of NiTi. A combination of nanoindentation and AES was employed to understand the relationship between mechanical properties and composition of the modified material.

  4. Model development of plasma implanted hydrogenic diffusion and trapping in ion beam damaged tungsten

    NASA Astrophysics Data System (ADS)

    Barton, J. L.; Wang, Y. Q.; Doerner, R. P.; Tynan, G. R.

    2016-10-01

    A Cu ion beam is used to induce controlled levels of damage (10-3, 10-2, and 10-1 dpa) in room temperature W samples. A single 5 MeV beam energy yielding a peaked damage profile 0.8 μm into the material, or three beam energies (0.5, 2, and 5 MeV) producing a relatively uniform damage profile from the near surface up to 0.8 μm were used. The W samples were then exposed to a D plasma ion fluence of 1024 ions m-2 at 380 K, and the resulting D retention was measured using the D(3He,p)4He reaction analysis (NRA) and thermal desorption spectroscopy (TDS). We observe that within experimental error there is no significant difference in retention whether the damage profile is peaked or uniform. The increase in retention is observed to increase proportional to \\text{dp}{{\\text{a}}0.66} estimated from the dpa peak calculated from the SRIM program. A simplified retention model is proposed that provides concentration profiles that can be directly compared to NRA data and total retention measurements. Taking the trapping energies due to three defect types calculated from density functional theory (DFT), the only free-parameters are three defect densities of in-grain monovacancies, dislocations, and grain boundary vacancies, and we assume these defects to be the dominant trapping locations. The model can fit D retention data in a pristine W sample within the experimental error of the measurements, and in subsequent modeling these intrinsic defect densities are then fixed. We model the retention profile after ion damage by adding the SRIM predicted vacancy profile to the intrinsic monovacancy defect density. Since the increase in retention, and therefore the increase in vacancy production, does not increase linearly with dpa, a correction factor is multiplied to the predicted vacancy profile to fit the data. A new diffusion coefficient is calculated with the model that is a function of the concentration of trapped atoms. This calculation may resolve discrepancies of various

  5. The microstructure of Si surface layers after plasma-immersion He(+) ion implantation and subsequent thermal annealing.

    PubMed

    Lomov, Andrey; Shcherbachev, Kirill; Chesnokov, Yurii; Kiselev, Dmitry

    2017-04-01

    The structural changes in the surface layer of p-type Cz-Si(001) samples after high-dose low-energy (2 keV) He(+) plasma-immersion ion implantation and subsequent thermal annealing were studied using a set of complementary methods: high-resolution X-ray reflectometry, high-resolution X-ray diffraction, transmission electron microscopy and atomic force microscopy. The formation of a three-layer structure was observed (an amorphous a-SiO x layer at the surface, an amorphous a-Si layer and a heavily damaged tensile-strained crystalline c-Si layer), which remained after annealing. Helium-filled bubbles were observed in the as-implanted sample. The influence of annealing on the evolution of the three-layer structure and the bubbles is considered. The bubbles are shown to grow after annealing. Their characteristic size is determined to be in the range of 5-20 nm. Large helium-filled bubbles are located in the amorphous a-Si layer. Small bubbles form inside the damaged crystalline Si layer. These bubbles are a major source of tensile strain in the c-Si layer.

  6. The microstructure of Si surface layers after plasma-immersion He+ ion implantation and subsequent thermal annealing1

    PubMed Central

    Lomov, Andrey; Shcherbachev, Kirill; Chesnokov, Yurii

    2017-01-01

    The structural changes in the surface layer of p-type Cz-Si(001) samples after high-dose low-energy (2 keV) He+ plasma-immersion ion implantation and subsequent thermal annealing were studied using a set of complementary methods: high-resolution X-ray reflectometry, high-resolution X-ray diffraction, transmission electron microscopy and atomic force microscopy. The formation of a three-layer structure was observed (an amorphous a-SiOx layer at the surface, an amorphous a-Si layer and a heavily damaged tensile-strained crystalline c-Si layer), which remained after annealing. Helium-filled bubbles were observed in the as-implanted sample. The influence of annealing on the evolution of the three-layer structure and the bubbles is considered. The bubbles are shown to grow after annealing. Their characteristic size is determined to be in the range of 5–20 nm. Large helium-filled bubbles are located in the amorphous a-Si layer. Small bubbles form inside the damaged crystalline Si layer. These bubbles are a major source of tensile strain in the c-Si layer. PMID:28381978

  7. Hydrogen engineering via plasma immersion ion implantation and flash lamp annealing in silicon-based solar cell substrates

    NASA Astrophysics Data System (ADS)

    Bregolin, F. L.; Krockert, K.; Prucnal, S.; Vines, L.; Hübner, R.; Svensson, B. G.; Wiesenhütter, K.; Möller, H.-J.; Skorupa, W.

    2014-02-01

    Higher conversion efficiencies while reducing costs at the same time is the ultimate goal driving the advancement of solar cell development. In this work, solar cell emitters are formed in Si substrates by plasma immersion ion implantation (PIII) of phosphine and posterior millisecond-range flash lamp annealing (FLA). In Si-based solar cells, hydrogen plays a fundamental role due to its excellent passivation properties. The optical and electrical properties of the fabricated emitters will be studied, with particular interest in their dependence on the hydrogen content present in the samples. The influence of different FLA annealing parameters and a comparison with traditional thermal treatments such as rapid thermal annealing (RTA) and furnace annealing (FA) will be presented. The samples treated by FLA at 1200 °C for 20 ms in forming gas show sheet resistance values of the order of 60 Ω/◻, and minority carrier diffusion lengths in the range of ˜200 μm without the use of a capping layer for surface passivation. Those results are significantly better than the ones observed from RTA or FA annealed samples. The simultaneous implantation of hydrogen during the doping process, combined with optimal FLA annealing parameters, gave promising results for the application of this technology in replacing the conventional POCl3 deposition and diffusion.

  8. Mechanical properties of nitrogen-rich surface layers on SS304 treated by plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Fernandes, B. B.; Mändl, S.; Oliveira, R. M.; Ueda, M.

    2014-08-01

    The formation of hard and wear resistant surface regions for austenitic stainless steel through different nitriding and nitrogen implantation processes at intermediate temperatures is an established technology. As the inserted nitrogen remains in solid solution, an expanded austenite phase is formed, accounting for these surface improvements. However, experiments on long-term behavior and exact wear processes within the expanded austenite layer are still missing. Here, the modified layers were produced using plasma immersion ion implantation with nitrogen gas and had a thickness of up to 4 μm, depending on the processing temperature. Thicker layers or those with higher surface nitrogen contents presented better wear resistance, according to detailed microscopic investigation on abrasion, plastic deformation, cracking and redeposition of material inside the wear tracks. At the same time, cyclic fatigue testing employing a nanoindenter equipped with a diamond ball was carried out at different absolute loads and relative unloadings. As the stress distribution between the modified layer and the substrate changes with increasing load, additional simulations were performed for obtaining these complex stress distributions. While high nitrogen concentration and/or thicker layers improve the wear resistance and hardness, these modifications simultaneously reduce the surface fatigue resistance.

  9. Study rationale and protocol: prospective randomized comparison of metal ion concentrations in the patient's plasma after implantation of coated and uncoated total knee prostheses

    PubMed Central

    Lützner, Jörg; Dinnebier, Gerd; Hartmann, Albrecht; Günther, Klaus-Peter; Kirschner, Stephan

    2009-01-01

    Background Any metal placed in a biological environment undergoes corrosion. Thus, with their large metallic surfaces, TKA implants are particularly prone to corrosion with subsequent release of metal ions into the human body which may cause local and systemic toxic effects and hypersensitivity reactions, and increase cancer risk. To address this problem, a new 7-layer zirconium coating developed especially for cobalt-chrome orthopaedic implants was tested biomechanically and found to lower metal ion release. The purpose of the proposed clinical trial is to compare the metal ion concentration in patients' plasma before and after implantation of a coated or uncoated TKA implant. Methods/Design In this randomised controlled trial, 120 patients undergoing primary TKA will be recruited at the Department of Orthopaedic Surgery of the University Hospital in Dresden, Germany, and randomised to either the coated or uncoated prosthesis. Outcome assessments will be conducted preoperatively and at 3 months, 12 months and 5 years postoperatively. The primary clinical endpoint will be the chromium ion concentration in the patient's plasma after 1 and 5 years. Secondary outcomes include cobalt, molybdenum and nickel ion concentrations after 1 and 5 years, allergy testing for hypersensitivity against one of these metals, the Knee Society Score to assess clinical and physical function of the knee joint, the self-assessment Oxford Score and the Short Form 36 quality of live questionnaire. Discussion The metal ion concentration in the patient's plasma has been shown to increase after TKA, its eventual adverse effects being widely debated. In the light of this discussion, ways to reduce metal ion release from orthopaedic implants should be studied in detail. The results of this investigation may lead to a new method to achieve this goal. Trials register Clinicaltrials registry NCT00862511 PMID:19828019

  10. Characteristics and anticoagulation behavior of polyethylene terephthalate modified by C2H2 plasma immersion ion implantation-deposition

    NASA Astrophysics Data System (ADS)

    Wang, J.; Pan, C. J.; Kwok, S. C. H.; Yang, P.; Chen, J. Y.; Wan, G. J.; Huang, N.; Chu, P. K.

    2004-01-01

    Acetylene (C2H2) plasma immersion ion implantation-deposition (PIII-D) is conducted on polyethylene terephthalate (PET) to improve its blood compatibility. The structural and physicochemical properties of the modified surface are characterized by, Raman spectroscopy, x-ray photoelectron spectroscopy (XPS), and static contact angle measurement. Atomic force microscopy discloses that the average roughness (Ra) of film surface decreases from 58.9 nm to 11.4 nm after C2H2 PIII-D treats PET. Attenuated total reflection Fourier transform infrared spectroscopy shows that the specfic adsorption peaks for PET decrease after ion implantation and deposition. Raman spectroscopy indicates that a thin amorphous polymerlike carbon (PLC) film is formed in the PET. The effects of the surface modification on the chemical bonding of C, H, and O are examined by XPS and the results show that the ratio of sp3 C-C to sp2 C=C is 0.25. After C2H2 PIII-D, the polar component γp of surface energy increases from 2.4 mN/m to 12.3 mN/m and γp/γd increases from 0.06 to 0.35. The wettability of the modified surfaces is improved. Scanning electron microscopy and optical microscopy reveal that the amounts of adhered, aggregated and morphologically changed platelets are reduced by the deposition of an amorphous polymer-like carbon film. The thrombin time, prothrombin time, and activated partial thromboplastin time of the modified PET are longer than those of the untreated PET. Our result thus shows that the amorphous PLC film deposited on the PET surface by C2H2 PIII-D improves platelet adhesion and activation. .

  11. Semiconductor Ion Implanters

    SciTech Connect

    MacKinnon, Barry A.; Ruffell, John P.

    2011-06-01

    In 1953 the Raytheon CK722 transistor was priced at $7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at $6.2 billion. Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing 'only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around $2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  12. Semiconductor Ion Implanters

    NASA Astrophysics Data System (ADS)

    MacKinnon, Barry A.; Ruffell, John P.

    2011-06-01

    In 1953 the Raytheon CK722 transistor was priced at 7.60. Based upon this, an Intel Xeon Quad Core processor containing 820,000,000 transistors should list at 6.2 billion! Particle accelerator technology plays an important part in the remarkable story of why that Intel product can be purchased today for a few hundred dollars. Most people of the mid twentieth century would be astonished at the ubiquity of semiconductors in the products we now buy and use every day. Though relatively expensive in the nineteen fifties they now exist in a wide range of items from high-end multicore microprocessors like the Intel product to disposable items containing `only' hundreds or thousands like RFID chips and talking greeting cards. This historical development has been fueled by continuous advancement of the several individual technologies involved in the production of semiconductor devices including Ion Implantation and the charged particle beamlines at the heart of implant machines. In the course of its 40 year development, the worldwide implanter industry has reached annual sales levels around 2B, installed thousands of dedicated machines and directly employs thousands of workers. It represents in all these measures, as much and possibly more than any other industrial application of particle accelerator technology. This presentation discusses the history of implanter development. It touches on some of the people involved and on some of the developmental changes and challenges imposed as the requirements of the semiconductor industry evolved.

  13. Two-wavelength Raman study of poly(ethylene terephthalate) surfaces modified by helium plasma-based ion implantation

    NASA Astrophysics Data System (ADS)

    Veres, M.; Tóth, A.; Mohai, M.; Bertóti, I.; Szépvölgyi, J.; Tóth, S.; Himics, L.; Koós, M.

    2012-12-01

    The surface of poly(ethylene terephthalate) (PET) was modified by helium plasma-based ion implantation (He PBII). The untreated and surface modified samples were characterised with optical absorption spectroscopy and two-wavelength micro-Raman spectroscopy excited with 488 nm and 785 nm light sources, allowing to examine the chemical bonding configuration of the surface layers on different depths and by selective enhancement of vibrations of different structural units. Upon treatment, simultaneously with the development of the broad D and G bands, a gradual decrease of the peaks corresponding to the Cdbnd C stretching and Cdbnd O stretching modes were observed with both excitations. Downshifting and broadening were detected for the Cdbnd C peak with both excitations and also for the Cdbnd O peak with the 488 nm excitation due to formation of condensed aromatic rings. Oppositely, upshifting was found with 785 nm excitation for the Cdbnd O peak and especially for its broad shoulder newly developed at the high wavenumber side. The latter feature was assigned to Cdbnd O groups attached to polymer chains without conjugation and the bands behaviour was interpreted by breaking of the Cdbnd C bonds of the polymer, leading to the formation of a crosslinked, disordered and stressed structure with still intact Cdbnd O groups, due to the increased nuclear damage at the end of the ion track.

  14. Influence of the residual oxygen in the plasma immersion ion implantation (PI3) processing of materials

    NASA Astrophysics Data System (ADS)

    Ueda, M.; Silva, A. R.; Mello, Carina B.; Silva, G.; Reuther, H.; Oliveira, V. S.

    2011-12-01

    In this work, we investigated the effects of the contaminants present in the vacuum chamber of the PI3 system, in particular, the residual oxygen, which results in the formation of the oxide compounds on the surface and hence is responsible for the high implantation energies required to achieve reasonably thick treated layers. We used a mass spectrometer (RGA) with a quadruple filter to verify the composition of the residual vacuum and pressure of the elements present in the chamber. Initially we found a high proportion of residual oxygen in a vacuum with a pressure of 1 × 10 -3 Pa. Minimizing the residual oxygen percentage in about 80%, by efficient cleaning of the chamber walls and by improving the gas feeding process, we mitigated the formation of oxides during the PI3 process. Therefore we achieved a highly efficient PI3 processing obtaining implanted layers reaching about 50 nm, even in cases such as an aluminum alloy, where is very difficult to nitrogen implant at low energies. We performed nitrogen PI3 treatment of SS304 and Al7075 using pulses of only 3 kV and 15 × 10 -6 s at 1 kHz with an operating pressure of 1 Pa.

  15. Photoelectrocatalytic properties of nitrogen doped TiO2/Ti photoelectrode prepared by plasma based ion implantation under visible light.

    PubMed

    Han, Lei; Xin, Yanjun; Liu, Huiling; Ma, Xinxin; Tang, Guangze

    2010-03-15

    Nitrogen doped TiO(2)/Ti photoelectrodes were prepared by a sequence of anodization and plasma based ion implantation (PBII). The properties of this photoelectrode were characterized by scanning electronic microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectrometry (XPS), Ultra violet/visible light diffuse reflectance spectra (UV/vis/DRS), surface photovoltage (SPV), etc. Photoelectrocatalytic (PEC) performance of N-doped TiO(2)/Ti photoelectrode was tested under visible light irradiation. Their photocatalytic activity was evaluated by degradation of Rhodamine B (Rh.B). The results of XPS showed that nitrogen element was in form of three species, i.e. beta-N, molecular gamma-N and O-Ti-N, which existed in the lattices of TiO(2) and gaps between molecules. The results of UV/vis/DRS spectra and SPV revealed that proper doping of nitrogen could expand the response of photoelectrodes towards visible light and diminish the recombination of photo-generated holes and electrons, respectively. The photoelectrocatalytic activity of N-doped TiO(2)/Ti photoelectrodes was superior to those of undoped one under visible light region irradiation.

  16. Ion implantation technology and ion sources

    NASA Astrophysics Data System (ADS)

    Sugitani, Michiro

    2014-02-01

    Ion implantation (I/I) technology has been developed with a great economic success of industries of VLSI (Very Large-Scale Integrated circuit) devices. Due to its large flexibility and good controllability, the I/I technology has been assuming various challenging requirements of VLSI evolutions, especially in advanced evolutional characteristics of CMOSFET. Here, reviewing the demands of VLSI manufacturing to the I/I technology, required characteristics of ion implanters, and their ion sources are discussed.

  17. Graphene synthesis by ion implantation

    PubMed Central

    Garaj, Slaven; Hubbard, William; Golovchenko, J. A.

    2010-01-01

    We demonstrate an ion implantation method for large-scale synthesis of high quality graphene films with controllable thickness. Thermally annealing polycrystalline nickel substrates that have been ion implanted with carbon atoms results in the surface growth of graphene films whose average thickness is controlled by implantation dose. The graphene film quality, as probed with Raman and electrical measurements, is comparable to previously reported synthesis methods. The implantation synthesis method can be generalized to a variety of metallic substrates and growth temperatures, since it does not require a decomposition of chemical precursors or a solvation of carbon into the substrate. PMID:21124725

  18. Ion sources for ion implantation technology (invited)

    NASA Astrophysics Data System (ADS)

    Sakai, Shigeki; Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki

    2014-02-01

    Ion sources for ion implantation are introduced. The technique is applied not only to large scale integration (LSI) devices but also to flat panel display. For LSI fabrication, ion source scheduled maintenance cycle is most important. For CMOS image sensor devices, metal contamination at implanted wafer is most important. On the other hand, to fabricate miniaturized devices, cluster ion implantation has been proposed to make shallow PN junction. While for power devices such as silicon carbide, aluminum ion is required. For doping processes of LCD fabrication, a large ion source is required. The extraction area is about 150 cm × 10 cm, and the beam uniformity is important as well as the total target beam current.

  19. Ion sources for ion implantation technology (invited)

    SciTech Connect

    Sakai, Shigeki Hamamoto, Nariaki; Inouchi, Yutaka; Umisedo, Sei; Miyamoto, Naoki

    2014-02-15

    Ion sources for ion implantation are introduced. The technique is applied not only to large scale integration (LSI) devices but also to flat panel display. For LSI fabrication, ion source scheduled maintenance cycle is most important. For CMOS image sensor devices, metal contamination at implanted wafer is most important. On the other hand, to fabricate miniaturized devices, cluster ion implantation has been proposed to make shallow PN junction. While for power devices such as silicon carbide, aluminum ion is required. For doping processes of LCD fabrication, a large ion source is required. The extraction area is about 150 cm × 10 cm, and the beam uniformity is important as well as the total target beam current.

  20. Characteristics of diamond-like carbon film synthesized on AISI 304 austenite stainless steel using plasma immersion ion implantation and deposition

    NASA Astrophysics Data System (ADS)

    Liang, J. H.; Chen, M. H.; Tsai, W. F.; Lee, S. C.; Ai, C. F.

    2007-04-01

    This study examines the characteristics of diamond-like carbon (DLC) film synthesized on AISI 304 austenite stainless steel by means of a hybrid process of plasma immersion ion implantation and deposition (PIII&D) maintained at 60 °C. The former and latter processes under investigation were carried out using methane (0-20 kV) and acetylene (1-2 kV, 0.13-0.40 Pa) plasmas, respectively. Glow discharge spectrometry (GDS), Raman scattering spectroscopy (RSS), atomic force microscopy (AFM), a nano-indentation probe (NIP) and a Rockwell-C hardness tester were employed to characterize, respectively, elemental depth profiles, sp3-to-sp2 ratio, surface morphology, hardness and adhesion strength of the DLC specimen. The results revealed that the mixing layer at the interface generated by plasma immersion ion implantation of methane at a higher voltage could enhance adhesive strength of the DLC film to the substrate. Furthermore, a higher sp3-to-sp2 ratio, a smoother surface, greater hardness, but weaker adhesion strength were obtained for the DLC film synthesized using plasma immersion ion deposition of acetylene at a lower bias voltage or higher gas pressure.

  1. Bioactivity of plasma implanted biomaterials

    NASA Astrophysics Data System (ADS)

    Chu, Paul K.

    2006-01-01

    Plasma immersion ion implantation and deposition (PIII&D) is an effective technique to enhance the surface bioactivity of materials. In this paper, recent progress made in our laboratory on plasma surface modification of biomedical materials is described. NiTi alloys have unique super-elastic and shape memory properties and are suitable for orthopedic implants but the leaching of toxic Ni may pose health hazards in humans. We have recently investigated the use of acetylene, oxygen and nitrogen PIII&D to prevent out-diffusion of nickel and good results have been obtained. Silicon is the most important material in the microelectronics industry but its surface biocompatibility has not been investigated in details. We have recently performed hydrogen PIII into silicon to improve the surface bioactivity and observed biomimetic growth of apatite on the surface in simulated body fluids. Diamond-like carbon (DLC) is widely used in the industry due to its excellent mechanical properties and chemical inertness and by incorporation of elements such as nitrogen and phosphorus, the surface blood compatibility can be improved. The properties as well as in vitro biological test results are discussed in this article.

  2. Highly Stripped Ion Sources for MeV Ion Implantation

    SciTech Connect

    Hershcovitch, Ady

    2009-06-30

    manufacturing industry by lowering power consumption by as much as 30 kW per ion implanter. Major problem was meeting commercialization goals did not succeed for the following reasons (which were discovered after R&D completion): record output of high charge state phosphorous would have thermally damage wafers; record high charge state of antimony requires tool (ion implanting machine in ion implantation jargon) modification, which did not make economic sense due to the small number of users. High fraction boron ion was delivered to PVI client Axcelis for retrofit and implantation testing; the source could have reduced beam preinjector power consumption by a factor of 3.5. But, since the source generated some lithium (though in miniscule amounts); last minute decision was made not to employ the source in implanters. An additional noteworthy reason for failure to commercialize is the fact that the ion implantation manufacturing industry had been in a very deep bust cycle. BNL, however, has benefited from advances in high-charge state ion generation, due to the need high charge state ions in some RHIC preinjectors. Since the invention of the transistor, the trend has been to miniaturize semiconductor devices. As semiconductors become smaller (and get miniaturized), ion energy needed for implantation decreases, since shallow implantation is desired. But, due to space charge (intra-ion repulsion) effects, forming and transporting ion beams becomes a rather difficult task. A few small manufacturers of low quality semiconductors use plasma immersion to circumvent the problem. However, in plasma immersion undesired plasma impurity ions are also implanted; hence, the quality of those semiconductors is poor. For high quality miniature semiconductor manufacturing, pure, low energy ion beams are utilized. But, low energy ion implanters are characterized by low current (much lower than desirable) and, therefore, low production rates. Consequently, increasing the current of pure low energy

  3. Effect of nitrogen high temperature plasma based ion implantation on the creep behavior of Ti-6Al-4V alloy

    NASA Astrophysics Data System (ADS)

    Oliveira, A. C.; Oliveira, R. M.; Reis, D. A. P.; Carreri, F. C.

    2014-08-01

    Nitrogen high temperature plasma based ion implantation (HTPBII) performed on Ti-6Al-4V significantly improved the creep behavior of the alloy. Treatments were performed for 1 h at a working pressure of 4 mbar and negative high voltage pulses of 7.5 kV, 30 μs and 500 Hz were applied on the specimens heated at 800 °C and 900 °C, respectively. Microstructural characterization of the treated samples revealed the formation of nitrided layers, with simultaneous formation of TiN and Ti2N. The most intense peaks of these compounds were obtained at higher treatment temperature, probably due to the diffusion of nitrogen into titanium. The presence of nitrides caused surface hardening up to three times higher in comparison with untreated alloy. Constant load creep tests were conducted on a standard creep machine in air atmosphere, at stress level of 319 MPa at 600 °C. Significant reductions of the steady-state creep rates (ɛ) were measured for martensitic Ti-6Al-4V treated by nitrogen HTPBII, reaching minimum creep rates of 0.0318 h-1 in comparison with 0.1938 h-1 for untreated sample. The improvement of the creep resistance seems to be associated with the formation of a thick nitrided layer, which acts as a barrier to oxygen diffusion into the material. In addition, the increase of the grain size generated by the heating of the substrate during the treatment can affect some creep mechanisms, leading to a significant reduction of ɛ.

  4. Development of a microwave ion source for ion implantations

    SciTech Connect

    Takahashi, N. Murata, H.; Kitami, H.; Mitsubori, H.; Sakuraba, J.; Soga, T.; Aoki, Y.; Katoh, T.

    2016-02-15

    A microwave ion source is expected to have a long lifetime, as it has fewer consumables. Thus, we are in the process of developing a microwave ion source for ion implantation applications. In this paper, we report on a newly developed plasma chamber and the extracted P{sup +} beam currents. The volume of the plasma chamber is optimized by varying the length of a boron nitride block installed within the chamber. The extracted P{sup +} beam current is more than 30 mA, at a 25 kV acceleration voltage, using PH{sub 3} gas.

  5. Development of a microwave ion source for ion implantations

    NASA Astrophysics Data System (ADS)

    Takahashi, N.; Murata, H.; Kitami, H.; Mitsubori, H.; Sakuraba, J.; Soga, T.; Aoki, Y.; Katoh, T.

    2016-02-01

    A microwave ion source is expected to have a long lifetime, as it has fewer consumables. Thus, we are in the process of developing a microwave ion source for ion implantation applications. In this paper, we report on a newly developed plasma chamber and the extracted P+ beam currents. The volume of the plasma chamber is optimized by varying the length of a boron nitride block installed within the chamber. The extracted P+ beam current is more than 30 mA, at a 25 kV acceleration voltage, using PH3 gas.

  6. High current metal ion implantation

    NASA Astrophysics Data System (ADS)

    Brown, Ian G.

    1990-04-01

    This report summarizes the research and development that has been carried out at Lawrence Berkeley Laboratory to develop a novel kind of high current metal ion source for metallurgical surface modification application. In ion implantation, an energetic ion beam is injected into a solid surface with the result that the surface composition is changed. For the case when the surface is a metal, the tribological properties of the new metallurgical surface can be significantly improved over the unimplanted surface. Previously, however, very intense metal ion beams have not been available, and this has been an impedance to the development of the field. With the MEVVA (Metal Vapor Vacuum Arc) ion source, metal ion beam currents of very high intensity have become available. This report outlines the progress made under the funded program in the four areas addressed: development of the MEVVA ion source for ion implantation application; research on the ion beam characteristics and behavior; development of the ion implantation facility; metallurgical ion implantation research that was performed.

  7. Carbon, nitrogen, and oxygen ion implantation of stainless steel

    SciTech Connect

    Rej, D.J.; Gavrilov, N.V.; Emlin, D.

    1995-12-31

    Ion implantation experiments of C, N, and O into stainless steel have been performed, with beam-line and plasma source ion implantation methods. Acceleration voltages were varied between 27 and 50 kV, with pulsed ion current densities between 1 and 10 mA/cm{sup 2}. Implanted doses ranged from 0.5 to 3 {times} 10{sup 18}cm{sup -2}, while workpiece temperatures were maintained between 25 and 800 C. Implant concentration profiles, microstructure, and surface mechanical properties of the implanted materials are reported.

  8. Improvements of anti-corrosion and mechanical properties of NiTi orthopedic materials by acetylene, nitrogen and oxygen plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Poon, Ray W. Y.; Ho, Joan P. Y.; Liu, Xuanyong; Chung, C. Y.; Chu, Paul K.; Yeung, Kelvin W. K.; Lu, William W.; Cheung, Kenneth M. C.

    2005-08-01

    Nickel-titanium shape memory alloys (NiTi) are useful materials in orthopedics and orthodontics due to their unique super-elasticity and shape memory effects. However, the problem associated with the release of harmful Ni ions to human tissues and fluids has been raising safety concern. Hence, it is necessary to produce a surface barrier to impede the out-diffusion of Ni ions from the materials. We have conducted acetylene, nitrogen and oxygen plasma immersion ion implantation (PIII) into NiTi alloys in an attempt to improve the surface properties. All the implanted and annealed samples surfaces exhibit outstanding corrosion and Ni out-diffusion resistance. Besides, the implanted layers are mechanically stronger than the substrate underneath. XPS analyses disclose that the layer formed by C2H2 PIII is composed of mainly TiCx with increasing Ti to C concentration ratios towards the bulk. The nitrogen PIII layer is observed to be TiN, whereas the oxygen PIII layer is composed of oxides of Ti4+, Ti3+ and Ti2+.

  9. Mutation breeding by ion implantation

    NASA Astrophysics Data System (ADS)

    Yu, Zengliang; Deng, Jianguo; He, Jianjun; Huo, Yuping; Wu, Yuejin; Wang, Xuedong; Lui, Guifu

    1991-07-01

    Ion implantation as a new mutagenic method has been used in the rice breeding program since 1986, and for mutation breeding of other crops later. It has been shown, in principle and in practice, that this method has many outstanding advantages: lower damage rate; higher mutation rate and wider mutational spectrum. Many new lines of rice with higher yield rate; broader disease resistance; shorter growing period but higher quality have been bred from ion beam induced mutants. Some of these lines have been utilized for the intersubspecies hybridization. Several new lines of cotton, wheat and other crops are now in breeding. Some biophysical effects of ion implantation for crop seeds have been studied.

  10. Plasma and ion beam processing at Los Alamos

    SciTech Connect

    Rej, D.J.; Davis, H.A.; Henins, I.

    1994-07-01

    Efforts are underway at Los Alamos National Laboratory to utilize plasma and intense ion beam science and technology of the processing of advanced materials. A major theme involves surface modification of materials, e.g., etching, deposition, alloying, and implantation. In this paper, we concentrate on two programs, plasma source ion implantation and high-intensity pulsed ion beam deposition.

  11. Ion implanted dielectric elastomer circuits

    NASA Astrophysics Data System (ADS)

    O'Brien, Benjamin M.; Rosset, Samuel; Anderson, Iain A.; Shea, Herbert R.

    2013-06-01

    Starfish and octopuses control their infinite degree-of-freedom arms with panache—capabilities typical of nature where the distribution of reflex-like intelligence throughout soft muscular networks greatly outperforms anything hard, heavy, and man-made. Dielectric elastomer actuators show great promise for soft artificial muscle networks. One way to make them smart is with piezo-resistive Dielectric Elastomer Switches (DES) that can be combined with artificial muscles to create arbitrary digital logic circuits. Unfortunately there are currently no reliable materials or fabrication process. Thus devices typically fail within a few thousand cycles. As a first step in the search for better materials we present a preliminary exploration of piezo-resistors made with filtered cathodic vacuum arc metal ion implantation. DES were formed on polydimethylsiloxane silicone membranes out of ion implanted gold nano-clusters. We propose that there are four distinct regimes (high dose, above percolation, on percolation, low dose) in which gold ion implanted piezo-resistors can operate and present experimental results on implanted piezo-resistors switching high voltages as well as a simple artificial muscle inverter. While gold ion implanted DES are limited by high hysteresis and low sensitivity, they already show promise for a range of applications including hysteretic oscillators and soft generators. With improvements to implanter process control the promise of artificial muscle circuitry for soft smart actuator networks could become a reality.

  12. Ion implantation damage in solids

    NASA Astrophysics Data System (ADS)

    Zhong, Yuncheng

    Ion implantation damage in silicon and ion irradiation induced surface smoothing and roughening process on metal and metallic alloys were studied. Defects were produced in Si by ion implantation. The initial state of damage, the onset temperature of interstitial mobility, the broader annealing behavior of the defects and the effect of surface on damage accumulation were studied using diffuse X-ray scattering, high resolution X-ray diffraction and transmission electron microscopy methods. A critical dose was observed during self-ion irradiation at 100°C for the conversion of small three-dimensional clusters in two-dimensional dislocation loops. The annealing behavior following self-ion irradiations shows different behavior from that following irradiation with inert gas ions. The surface was shown to be an effective sink for defects and that it plays an important role in defect accumulation during low energy implantation. Ion induced surface smoothing and roughening processes were studied using Molecular Dynamics (MD) computer simulation. The simulations on self-ion bombarded W showed the effect of the surface on defect production and the roughening of the surface. The simulations on the CuTi, Ag and Ni with amorphous and crystalline states reveal the smoothing and roughening process due to a single ion impact.

  13. PULSION registered: A Versatile 200 to 300 mm Bridge Tool Plasma Immersion Ion Implanter for Ultra-Shallow Doping and Nanotechology Applications

    SciTech Connect

    Torregrosa, Frank; Etienne, Hasnaa; Sempere, Guillaume; Mathieu, Gilles; Roux, Laurent; Milesi, Frederic; Gonzatti, Frederic

    2008-11-03

    Thanks to the European Projects SEA-NET and PULLNANO, an industrial version of the IBS Plasma Ion Implantation tool has been installed in LETI for the fabrication of Ultra-Shallow Junctions for 45 and 32 nm CMOS on 200 and 300 mm wafers. In this paper, we present the main machine characteristics (layout, contamination, homogeneity, reproducibility, uptime) and we show that implanted wafers are compatible with the 32 nm nodes requirements. Then doping results (sheet resistance vs junction depth and leakage current) using several annealing technics are presented (laser, flash and spike anneals). In the second part of the paper, versatility of the tool is demonstrated with its use for other applications (3D doping, hydrogenation, solar cells...)

  14. Co(II)-mediated effects of plain and plasma immersion ion implanted cobalt-chromium alloys on the osteogenic differentiation of human mesenchymal stem cells.

    PubMed

    Schröck, Kathleen; Lutz, Johanna; Mändl, Stephan; Hacker, Michael C; Kamprad, Manja; Schulz-Siegmund, Michaela

    2015-03-01

    Medical CoCr is one of the main alloys used for metal-on-metal prosthesis in patients with total hip arthroplasty. CoCr surfaces modified by nitrogen plasma immersion ion implantation (PIII) are characterized by improved wear resistance but also showed increased Co(II) ion release under in vitro conditions. For the first time, CoCr modified by nitrogen PIII was evaluated with regard to its effect on the osteogenic differentiation of MSC. The activity of alkaline phosphatase, the expression of the osteogenic genes Runt-related transcription factor 2, osteopontin as well as integrin-binding bone sialoprotein and the production of osteocalcin and hydroxyapatite were determined. The results of our study demonstrate that Co(II) ions released from the alloy affected the osteogenic differentiation of MSC. Distinct differences in differentiation markers were found between pristine and modified alloys for osteocalcin but not for integrin-binding sialoprotein and hydroxyapatite. Interestingly, osteopontin was upregulated in naive and differentiated MSC by Co(II) ions and modified CoCr, likely through the induction of a cellular hypoxic response. The findings of this study contribute to a better understanding of possible risk factors with regard to a clinical applicability of surface modified CoCr implant materials.

  15. Surface modification by nitrogen plasma immersion ion implantation into new steel 460Li-21Cr in a capacitively coupled radio frequency discharge

    NASA Astrophysics Data System (ADS)

    Bhuyan, H.; Mändl, S.; Bora, B.; Favre, M.; Wyndham, E.; Maze, J. R.; Walczak, M.; Manova, D.

    2014-10-01

    A novel steel 460Li-21Cr belonging to a new generation of superferritic grade steel has been implanted with nitrogen in a low power 13.56 MHz radio frequency plasma by the plasma immersion ion implantation (PIII) technique in order to study its physical and chemical properties under different experimental conditions. We observed improved hardness and wear behavior of 460Li-21Cr steel with a layer thickness between 1.5 and 4.0 μm after 60 min implantation in the temperature range from 350 to 550 °C. The modified surface layer containing nitrogen does not show CrN in X-ray diffraction (XRD). Compared to untreated substrates, the hardness can be increased by a factor of 4, depending on the experimental conditions, and the wear behavior was also improved by two orders of magnitude. The results are very similar to those for austenitic stainless steel with a similar pronounced increase in wear resistance and plateau-like nitrogen depth profiles.

  16. Totem pole drive decks for the high-voltage, pulsed-power modulator for a large-scale plasma source ion implantation system

    SciTech Connect

    Gribble, R.J.; Reass, W.A.

    1993-07-01

    Plasma source ion implantation (PSII) is an industrially-relevant technique to change the surface composition of materials, thereby improving the mechanical, chemical, electrical, or optical properties. Pre-manufactured parts are immersed in a plasma and are pulsed with a high voltage source that accelerates the ions to the surface, where they become implanted, modifying the surface characteristics. The high voltage applied to the ``workpiece`` is supplied by a high-voltage, pulsed-power modulator capable of operating to 120 kV, with an output pulse width to 20 uS at a repetition rate of up to 2 kHz. Output currents of up to 60 A, and average powers of 225 kW (6.6 MW peak) will be the ultimate capability. Initial system start-up will be limited by a 60 kV, 1 A charging power supply. This paper describes the totem pole drive decks, the ``on`` deck and ``off`` deck, used as a pre-driver to the main high voltage switch tubes which applies power to the workpiece. The pulse length and frequency are externally controlled and then fiber-optically coupled to the modulator totem pole drive decks. The circuitry of the planar triode drivers will be presented in addition to experimental results.

  17. Influence of surface modification of nitinol with silicon using plasma-immersion ion implantation on the alloy corrosion resistance in artificial physiological solutions

    NASA Astrophysics Data System (ADS)

    Kashin, O. A.; Borisov, D. P.; Lotkov, A. I.; Abramova, P. V.; Korshunov, A. V.

    2015-10-01

    Cyclic voltammetry and potentiostatic polarization have been applied to study electrochemical behavior and to determine corrosion resistance of nitinol, which surface was modified with silicon using plasma-immersion ion implantation, in 0.9% NaCl solution and in artificial blood plasma. It was found out that continuous, and also homogeneous in composition, thin Si-containing layers are resistant to corrosion damage at high positive potentials in artificial physiological solutions due to formation of stable passive films. Breakdown potential Eb of Si-modified NiTi depends on the character of silicon and Ni distribution at the alloy surface, Eb values amounted to 0.9-1.5 V (Ag/AgCl/KCl sat.) for the alloy samples with continuous Si-containing surface layers and with decreased Ni surface concentration.

  18. Oxygen depth profiling by resonant backscattering and glow discharge optical emission spectroscopy of Ti-6Al-4V alloy oxidized by ion implantation and plasma based treatment

    NASA Astrophysics Data System (ADS)

    Nsengiyumva, S.; Topic, M.; Pichon, L.; Comrie, C. M.; Mtshali, C.

    2016-10-01

    Oxygen depth profiling by means of 16O(α,α)16O backscattering and glow discharge optical emission spectroscopy (GDOES) was investigated in two different sets of Ti-6Al-4V samples. The first set was made of Ti-6Al-4V samples implanted at room temperature and 550 °C with 50 and 150 keV O+ ions at fluences ranging from 1.5 × 1017 to 6.0 × 1017 ions/cm2. The second set consisted of Ti-6Al-4V samples treated at 550 °C for 7 h and 24 h under low pressure (8 Pa) oxygen, eventually with RF plasma activation. These results are part of a wider investigation on Ti-6Al-4V motivated by recent publications which have shown that an oxide layer can enhance hydrogen absorption and can then promote Ti-6Al-4V alloys as efficient hydrogen storage materials. The results obtained by the two characterization techniques were compared and discussed, enabling to adjust the dependence to the oxygen concentration of the sputtering rates to be used in the time-to-depth transformation required in GDOES analysis. Considering the low thickness of oxidized alloy, usual procedures employed in GDOES depth calculation were indeed not adapted. Once calibrated thanks to the resonant RBS, GDOES can then be easily employed as fast characterization of oxidized and/or hydrogenated surface of Ti-6Al-4V. The obtained results show that the oxygen content into the surface oxidized layer slightly increases in samples implanted at higher fluence and higher temperature. However the overall oxidized layer thickness (<200 nm) remains within the projected ion depth range and is not significantly increased by thermal diffusion at 550 °C. Taken into account the initial oxide layer, the incorporated oxygen quantity mainly corresponds to the implanted fluence but it can be slightly higher with 550 °C implantation, indicating a slight additional oxidation by residual oxygen or surface contamination. The oxygen penetrations and contents in samples oxidized by thermally activated diffusion treatments were more

  19. A novel method for effective sodium ion implantation into silicon.

    PubMed

    Lu, Qiu Yuan; Chu, Paul K

    2012-07-01

    Although sodium ion implantation is useful to the surface modification of biomaterials and nano-electronic materials, it is a challenging to conduct effective sodium implantation by traditional implantation methods due to its high chemical reactivity. In this paper, we present a novel method by coupling a Na dispenser with plasma immersion ion implantation and radio frequency discharge. X-ray photoelectron spectroscopy (XPS) depth profiling reveals that sodium is effectively implanted into a silicon wafer using this apparatus. The Na 1s XPS spectra disclose Na(2)O-SiO(2) bonds and the implantation effects are confirmed by tapping mode atomic force microscopy. Our setup provides a feasible way to conduct sodium ion implantation effectively.

  20. A novel method for effective sodium ion implantation into silicon

    SciTech Connect

    Lu Qiuyuan; Chu, Paul K.

    2012-07-15

    Although sodium ion implantation is useful to the surface modification of biomaterials and nano-electronic materials, it is a challenging to conduct effective sodium implantation by traditional implantation methods due to its high chemical reactivity. In this paper, we present a novel method by coupling a Na dispenser with plasma immersion ion implantation and radio frequency discharge. X-ray photoelectron spectroscopy (XPS) depth profiling reveals that sodium is effectively implanted into a silicon wafer using this apparatus. The Na 1s XPS spectra disclose Na{sub 2}O-SiO{sub 2} bonds and the implantation effects are confirmed by tapping mode atomic force microscopy. Our setup provides a feasible way to conduct sodium ion implantation effectively.

  1. Ion Implanted Gaas Integrated Optics Fabrication Technology

    NASA Astrophysics Data System (ADS)

    Mentzer, M. A.; Hunsperger, R. G.; Bartko, J.; Zavada, J. M.; Jenkinson, H. A.

    1985-01-01

    Ion implantation of semiconductor materials is a fabrication technique that offers a number of distinct advantages for the formation of guided-wave components and microelectronic devices. Implanted damage and dopants produce optical and electronic changes that can be utilized for sensing and signal processing applications. GaAs is a very attractive material for optical fabrication since it is transparent out to the far infrared. It can be used to fabricate optical waveguides, directional couplers, EO modulators, and detectors, as well as other guided wave structures. The presence of free carriers in GaAs lowers the refractive index from that of the pure semiconductor material. This depression of the refractive index is primarily due to the negative contribution of the free carrier plasma to the dielectric constant of the semiconductor. Bombardment of n-type GaAs by protons creates damage sites near the surface of the crystal structure where free carriers are trapped. This "free carrier compensated" region in the GaAs has a higher refractive index than the bulk region. If the compensated region is sufficiently thick and has a refractive index which is sufficiently larger than that of the bulk n-type region, an optical waveguide is formed. In this paper, a description of ion implantation techniques for the fabrication of both planar and channel integrated optical structures in GaAs is presented, and is related to the selection of ion species, implant energy and fluence, and to the physical processes involved. Lithographic technology and masking techniques are discussed for achieving a particular desired implant profile. Finally, the results of a set of ion implantation experiments are presented.

  2. Osteogenic activity and antibacterial effect of zinc ion implanted titanium.

    PubMed

    Jin, Guodong; Cao, Huiliang; Qiao, Yuqin; Meng, Fanhao; Zhu, Hongqin; Liu, Xuanyong

    2014-05-01

    Titanium (Ti) and its alloys are widely used as orthopedic and dental implants. In this work, zinc (Zn) was implanted into oxalic acid etched titanium using plasma immersion ion implantation technology. Scanning electron microscopy and X-ray photoelectron spectroscopy were used to investigate the surface morphology and composition of Zn-implanted titanium. The results indicate that the depth profile of zinc in Zn-implanted titanium resembles a Gaussian distribution, and zinc exists in the form of ZnO at the surface whereas in the form of metallic Zn in the interior. The Zn-implanted titanium can significantly stimulate proliferation of osteoblastic MC3T3-E1 cells as well as initial adhesion, spreading activity, ALP activity, collagen secretion and extracellular matrix mineralization of the rat mesenchymal stem cells. The Zn-implanted titanium presents partly antibacterial effect on both Escherichia coli and Staphylococcus aureus. The ability of the Zn-implanted titanium to stimulate cell adhesion, proliferation and differentiation as well as the antibacterial effect on E. coli can be improved by increasing implantation time even to 2 h in this work, indicating that the content of zinc implanted in titanium can easily be controlled within the safe concentration using plasma immersion ion implantation technology. The Zn-implanted titanium with excellent osteogenic activity and partly antibacterial effect can serve as useful candidates for orthopedic and dental implants. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Surface Modification of Orthodontic Bracket Models via Ion Implantation: Effect on Coefficients of Friction

    DTIC Science & Technology

    1989-01-01

    This finding is suggestive of carbon contamination resulting from vacuum carburization which may well have occurred during the other implantations but...Analyzing Column Ion Separating Manei --------- Quadrupole Endstation Ion Extraction/ Preacceleration Plasma N-7 Magnet Filament (Cathode) Ion

  4. Synthesis of unattainable ion implantation profiles — 'Pseudo-implantation'

    NASA Astrophysics Data System (ADS)

    Brown, I. G.; Anders, A.; Anders, S.; Castro, R. A.; Dickinson, M. R.; MacGill, R. A.; Wang, Z.

    1995-12-01

    Metal implantation provides a powerful tool for the formation of non-equilibrium alloy layers for a wide variety of basic and applied materials applications, but the technique is fundamentally limited in two important ways: (i) the implanted species concentration is limited by sputtering of the modified layer by the incident ion beam itself, and the sputter-limited retained dose is often disappointingly low; (ii) the thickness of the modified layer is limited by the maximum ion energy available, and for practical reasons (implanter voltage) the layer thickness is often just a few hundred ångströms. We describe here a metal-plasma-immersion-based method for synthesizing non-equilibrium alloy layers of arbitrarily high dopant concentration and of arbitrary thickness. By repetitively pulse biasing the substrate to high negative voltage while it is immersed in the metal plasma from a vacuum arc plasma gun, a layer can be synthesized that is atomically mixed into the substrate with an interface width determined by the early-time bias voltage and with a thickness determined by the overall duration of the process. The species is that of the vacuum arc cathode material, which for this purpose can be a mixture of the substrate metal and the wanted dopant metal. We have used the method to form a high concentration Ta layer on the copper rails of an electromagnetic rail gun, with total surface area treated about 3000 cm 2; the Ta depth profile was flat at about 50 at.% Ta in Cu to a depth of about 1000 Å.

  5. Progress towards a 20 kV, 2 kA plasma source ion implantation modulator for automotive production of diamond film on aluminum

    SciTech Connect

    Reass, W.A.; Munson, C.A.; Malaczynski, G.; Elmoursi, A.

    1996-11-01

    This paper provides the process requirements and the electrical design topology being developed to facilitate large scale production of amorphous diamond films on aluminum. The patented recipe, that includes other surface modification processes, requires various operational voltages, duty cycles, and current load regimes to ensure a high quality film. It is desirable to utilize a common modulator design for this relatively low voltage recipe. Processing may include target part cleaning, ion implantation, plasma deposition, and vacuum chamber cleaning. Modulator performance will have a direct impact on plant size and system economics. Unfortunately, process requirements are in a regime that is not easily achievable by solid state or very efficiently by vacuum tube devices. To accommodate the various process requirements, the authors are developing a modulator based on series connected hot decks utilizing high current, high voltage IGBT devices.

  6. Preparation of Ag-containing diamond-like carbon films on the interior surface of tubes by a combined method of plasma source ion implantation and DC sputtering

    NASA Astrophysics Data System (ADS)

    Hatada, R.; Flege, S.; Bobrich, A.; Ensinger, W.; Dietz, C.; Baba, K.; Sawase, T.; Watamoto, T.; Matsutani, T.

    2014-08-01

    Adhesive diamond-like carbon (DLC) films can be prepared by plasma source ion implantation (PSII), which is also suitable for the treatment of the inner surface of a tube. Incorporation of a metal into the DLC film provides a possibility to change the characteristics of the DLC film. One source for the metal is DC sputtering. In this study PSII and DC sputtering were combined to prepare DLC films containing low concentrations of Ag on the interior surfaces of stainless steel tubes. A DLC film was deposited using a C2H4 plasma with the help of an auxiliary electrode inside of the tube. This electrode was then used as a target for the DC sputtering. A mixture of the gases Ar and C2H4 was used to sputter the silver. By changing the gas flow ratios and process time, the resulting Ag content of the films could be varied. Sample characterizations were performed by X-ray photoelectron spectroscopy, secondary ion mass spectrometry, atomic force microscopy and Raman spectroscopy. Additionally, a ball-on-disk test was performed to investigate the tribological properties of the films. The antibacterial activity was determined using Staphylococcus aureus bacteria.

  7. Hemocompatibility of nitrogen-doped, hydrogen-free diamond-like carbon prepared by nitrogen plasma immersion ion implantation-deposition.

    PubMed

    Kwok, Sunny C H; Yang, Ping; Wang, Jin; Liu, Xuanyong; Chu, Paul K

    2004-07-01

    Amorphous hydrogenated carbon (a-C:H) has been shown to be a potential material in biomedical devices such as artificial heart valves, bone implants, and so on because of its chemical inertness, low coefficient of friction, high wear resistance, and good biocompatibility. However, the biomedical characteristics such as blood compatibility of doped hydrogen-free diamond-like carbon (DLC) have not been investigated in details. We recently began to investigate the potential use of nitrogen-doped, hydrogen-free DLC in artificial heart valves. In our experiments, a series of hydrogen-free DLC films doped with nitrogen were synthesized by plasma immersion ion implantation-deposition (PIII-D) utilizing a pulsed vacuum arc plasma source and different N to Ar (FN/FAr) gas mixtures in the plasma chamber. The structures and properties of the film were evaluated by Raman spectroscopy, Rutherford backscattering spectrometry (RBS), and X-ray photoelectron spectroscopy (XPS). To assess the blood compatibility of the films and the impact on the blood compatibility by the presence of nitrogen, platelet adhesion tests were conducted. Our results indicate that the blood compatibility of both hydrogen-free carbon films (a-C) and amorphous carbon nitride films are better than that of low-temperature isotropic pyrolytic carbon (LTIC). The experimental results are consistent with the relative theory of interfacial energy and surface tension including both dispersion and polar components. Our results also indicate that an optimal fraction of sp2 bonding is desirable, but an excessively high nitrogen concentration degrades the properties to an extent that the biocompatibility can be worse than that of LTIC. Copyright 2004 Wiley Periodicals, Inc.

  8. The linker-free covalent attachment of collagen to plasma immersion ion implantation treated polytetrafluoroethylene and subsequent cell-binding activity.

    PubMed

    Bax, Daniel V; McKenzie, David R; Weiss, Anthony S; Bilek, Marcela M M

    2010-03-01

    It is desirable that polymers used for the fabrication of prosthetic implants promote biological functions such as cellular adhesion, differentiation and viability. In this study, we have used plasma immersion ion implantation (PIII) to modify the surface of polytetrafluoroethylene (PTFE), thereby modulating the binding mechanism of collagen. The amount of collagen bound to the polymer surface following PIII-treatment was similar to that bound by non-covalent physisorption. In a manner consistent with previous enzyme and tropoelastin binding data, the collagen bound to the PIII-treated PTFE surface was resistant to sodium dodecyl sulfate (SDS) elution whilst collagen bound to the untreated surface was fully removed. This demonstrates the capability of PIII-treated surfaces to covalently attach collagen without employing chemical linking molecules. Only the collagen bound to the PIII-treated PTFE surface supported human dermal fibroblast attachment and spreading. This indicates that collagen on the PIII-treated surface possesses increased adhesive activity as compared to that on the untreated surface. Cell adhesion was inhibited by EDTA when the collagen was bound to PIII-treated PTFE, as expected for integrin involvement. Additionally this adhesion was sensitive to the conformation of the bound collagen. Increased actin cytoskeletal assembly was observed on cells spreading onto collagen-coated PIII-treated PTFE compared to the collagen-coated untreated PTFE. These data demonstrate the retention of collagen's biological properties following its attachment to PIII-treated PTFE, suggesting advantages for tissue engineering and prosthetic design.

  9. Controlled ion implant damage profile for etching

    DOEpatents

    Arnold, Jr., George W.; Ashby, Carol I. H.; Brannon, Paul J.

    1990-01-01

    A process for etching a material such as LiNbO.sub.3 by implanting ions having a plurality of different kinetic energies in an area to be etched, and then contacting the ion implanted area with an etchant. The various energies of the ions are selected to produce implant damage substantially uniformly throughout the entire depth of the zone to be etched, thus tailoring the vertical profile of the damaged zone.

  10. Ion Implantation of Zinc Sulphide Thin Films,

    DTIC Science & Technology

    The report considers the use of ion implantation as a means of preparing rare earth doped thin films of zinc sulphide, and presents preliminary results on the luminescence of such films doped with Tb and Er166 ions. (Author)

  11. Improved bio-tribology of biomedical alloys by ion implantation techniques

    NASA Astrophysics Data System (ADS)

    Díaz, C.; Lutz, J.; Mändl, S.; García, J. A.; Martínez, R.; Rodríguez, R. J.

    2009-05-01

    Surface modification of biomaterials by conventional ion implantation (II) and plasma immersion ion implantation (PI3) are innovative methods to improve the biocompatibility of these advanced materials. This paper describes the biocompatibility improvements of Ti6Al4V and Co28Cr6Mo implanted with N and O in a conventional implantation and a plasma immersion ion implantation processes. Tribo-corrosion friction and wear tests were performed in a realistic environment - in Hank's solution - to investigate the introduced modifications. The wear performance was only slightly improved due to a thin layer thickness, whereas, in contrast, the corrosion rate was significantly reduced.

  12. Silicon on sapphire for ion implantation studies

    NASA Technical Reports Server (NTRS)

    Pisciotta, B. P.

    1974-01-01

    Van der Pauw or bridge samples are ultrasonically cut from silicon on sapphire wafers. Contact pad regions are implanted with moderately heavy dose of ions. Ion of interest is implanted into sample; and, before being annealed in vacuum, sample is sealed with sputtered layer of silicon dioxide. Nickel or aluminum is sputtered onto contact pad areas and is sintered in nitrogen atmosphere.

  13. Effect of CH4 Ion Implantation in Pure Aluminium

    NASA Astrophysics Data System (ADS)

    Sari, A. H.; Jabbari, A. R.; Ghoranneviss, M.

    2011-08-01

    In this paper, aluminium samples with 99.96% purity were exposed to ion beam, extracted from CH4 plasma. Implantation of ions were performed for 50 keV energy and various doses ranging from 1 × 1017 to 6 × 1017 ions/cm2. Morphology of surfaces, roughness and its evolution during variation of ion dose has been studied by atomic force microscopy (AFM). Microstructure of the modified surfaces after ion implantation has been obtained by X-ray diffraction technique and Raman spectroscopy. Formation of aluminium carbide (Al4C3) was confirmed by XRD results at implantation doses of 3 × 1017 and 6 × 1017 ions/cm2. In addition, it was observed that when the ion dose is increased, orientation of aluminium planes change from (2 2 0) to (2 0 0). Corrosion test was performed and compared for implanted and un-implanted samples. The results showed that corrosion resistivity increase by accumulation of ion dose.

  14. Surface modification of sapphire by ion implantation

    SciTech Connect

    McHargue, C.J.

    1998-11-01

    The range of microstructures and properties of sapphire (single crystalline Al{sub 2}O{sub 3}) that are produced by ion implantation are discussed with respect to the implantation parameters of ion species, fluence, irradiation temperature and the orientation of the ion beam relative to crystallographic axes. The microstructure of implanted sapphire may be crystalline with varying concentrations of defects or it may be amorphous perhaps with short-range order. At moderate to high fluences, implanted metallic ions often coalesce into pure metallic colloids and gas ions form bubbles. Many of the implanted microstructural features have been identified from studies using transmission electron microscopy (TEM), optical spectroscopy, Moessbauer spectroscopy, and Rutherford backscattering-channeling. The chemical, mechanical, and physical properties reflect the microstructures.

  15. Single atom devices by ion implantation.

    PubMed

    van Donkelaar, Jessica; Yang, C; Alves, A D C; McCallum, J C; Hougaard, C; Johnson, B C; Hudson, F E; Dzurak, A S; Morello, A; Spemann, D; Jamieson, D N

    2015-04-22

    To expand the capabilities of semiconductor devices for new functions exploiting the quantum states of single donors or other impurity atoms requires a deterministic fabrication method. Ion implantation is a standard tool of the semiconductor industry and we have developed pathways to deterministic ion implantation to address this challenge. Although ion straggling limits the precision with which atoms can be positioned, for single atom devices it is possible to use post-implantation techniques to locate favourably placed atoms in devices for control and readout. However, large-scale devices will require improved precision. We examine here how the method of ion beam induced charge, already demonstrated for the deterministic ion implantation of 14 keV P donor atoms in silicon, can be used to implant a non-Poisson distribution of ions in silicon. Further, we demonstrate the method can be developed to higher precision by the incorporation of new deterministic ion implantation strategies that employ on-chip detectors with internal charge gain. In a silicon device we show a pulse height spectrum for 14 keV P ion impact that shows an internal gain of 3 that has the potential of allowing deterministic implantation of sub-14 keV P ions with reduced straggling.

  16. Structural, mechanical and hydrophobic properties of fluorine-doped diamond-like carbon films synthesized by plasma immersion ion implantation and deposition (PIII?D)

    NASA Astrophysics Data System (ADS)

    Yao, Zh. Q.; Yang, P.; Huang, N.; Sun, H.; Wang, J.

    2004-05-01

    Fluorine-doped diamond-like carbon (a-C:F) films with different fluorine content were fabricated on Si wafer by plasma immersion ion implantation and deposition (PIII-D). Film composition and structure were characterized by X-ray photoelectron spectroscopy (XPS) and Raman scattering spectroscopy. Surface morphology and roughness were analyzed by atomic force microscopy (AFM). Hardness and scratch resistance were measured by nano-indentation and nano-scratch, respectively. Water contact angles were measured by sessile drop method. With the increase of the CF 4 flux, fluorine content was gradually increased to the film. Raman spectra indicates that these films have a diamond-like structure. The addition of fluorine to diamond-like carbon films had a critical influence on the film properties. The film surface becomes more smoother due to the etching behavior of F +. Hardness was significantly reduced, while the scratch resistance results show that these films have a fairly good adhesion to the substrate. Evident improvements of the hydrophobicity have been made to these films, with contact angles of double-stilled water approaching that of polytetrafluoroethylene (PTFE). Our study suggests that broad application regions of the fluorine-doped amorphous carbon films with diamond-like structure, synthesized by PIII-D, can be extended by combining the non-wetting properties and mechanical properties which are far superior to those of PTFE.

  17. Physical and Tribological Characteristics of Ion-Implanted Diamond Films

    NASA Technical Reports Server (NTRS)

    Miyoshi, K.; Heidger, S.; Korenyi-Both, A. L.; Jayne, D. T.; Herrera-Fierro, P.; Shogrin, B.; Wilbur, P. J.; Wu, R. L. C.; Garscadden, A.; Barnes, P. N.

    1994-01-01

    Unidirectional sliding friction experiments were conducted with a natural, polished diamond pin in contact with both as-deposited and carbon-ion-implanted diamond films in ultrahigh vacuum. Diamond films were deposited on silicon, silicon carbide, and silicon nitride by microwave-plasma-assisted chemical vapor deposition. The as-deposited diamond films were impacted with carbon ions at an accelerating energy of 60 keV and a current density of 50 micron A/cm(exp 2) for approximately 6 min, resulting in a dose of 1.2 x 10(exp 17) carbon ions/cm(exp 2). The results indicate that the carbon ion implantation produced a thin surface layer of amorphous, nondiamond carbon. The nondiamond carbon greatly decreased both friction and wear of the diamond films. The coefficients of friction for the carbon-ion-implanted, fine-grain diamond films were less than 0.1, factors of 20 to 30 lower than those for the as-deposited, fine-grain diamond films. The coefficients of friction for the carbon-ion-implanted, coarse-grain diamond films were approximately 0.35, a factor of five lower than those for the as-deposited, coarse-grain diamond films. The wear rates for the carbon-ion-implanted, diamond films were on the order of 10(exp -6) mm(exp 3)/Nm, factors of 30 to 80 lower than that for the as-deposited diamond films, regardless of grain size. The friction of the carbon-ion-implanted diamond films was greatly reduced because the amorphous, nondiamond carbon, which had a low shear strength, was restricted to the surface layers (less than 0.1 micron thick) and because the underlying diamond materials retained their high hardness. In conclusion, the carbon-ion-implanted, fine-grain diamond films can be used effectively as wear resistant, self-lubricating coatings for ceramics, such as silicon nitride and silicon carbide, in ultrahigh vacuum.

  18. Ion-implantation studies on perpendicular media.

    PubMed

    Gaur, Nikita; Maurer, Siegfried L; Nunes, Ronald W; Piramanayagam, S N; Bhatia, C S

    2011-03-01

    Magnetic and structural properties of ion implanted perpendicular recording media have been investigated. Effects of 12C+ ion implantation with the doses of 2 x 10(11), 10(13), 10(14) and 10(16) ions/cm2 in the magnetic recording layer of conventional granular and continuous perpendicular media are reported in this paper. Implantation with the highest fluence of 10(16) ions/cm2 resulted in change of the magnetization reversal mechanism, thereby reducing coercivity. In continuous media the implanted ions cause increase in pinning defects, leading to an increase in coercivity. In contrast, high dose was found to cause similar change in the crystallographic properties of both the granular and continuous media.

  19. Surface Protection and Improved Performance of Satellite Components as well as Mitigation of Space Environmental Pollution by Plasma Ion Implantation

    NASA Astrophysics Data System (ADS)

    Ueda, M.; Takahashi, W. K.; Marcondes, A. R.; Tan, I. H.; Silva, G.

    2009-01-01

    Three plasma processing systems based on PII technique have been used in the improvement of surface properties of different materials important for aerospace and space applications. Metal plasma PII of Al and Mg was used for surface protection of polymers used in space such as Kapton, Mylar and polyethylene. Al alloys were treated with nitrogen PII for improved resistance to corrosion aiming at aerospace applications. A rigid polymer UHMWPE was also treated in a nitrogen PII to produce a protective layer with DLC. Although not very light, SS304 stainless steel components are being used in a imaging camera in space, and some components made of this material showed endurance to vibration tests after nitrogen PII, therefore being qualified for on-board application.

  20. Surface Protection and Improved Performance of Satellite Components as well as Mitigation of Space Environmental Pollution by Plasma Ion Implantation

    SciTech Connect

    Ueda, M.; Takahashi, W. K.; Marcondes, A. R.; Tan, I. H.; Silva, G.

    2009-01-05

    Three plasma processing systems based on PII technique have been used in the improvement of surface properties of different materials important for aerospace and space applications. Metal plasma PII of Al and Mg was used for surface protection of polymers used in space such as Kapton, Mylar and polyethylene. Al alloys were treated with nitrogen PII for improved resistance to corrosion aiming at aerospace applications. A rigid polymer UHMWPE was also treated in a nitrogen PII to produce a protective layer with DLC. Although not very light, SS304 stainless steel components are being used in a imaging camera in space, and some components made of this material showed endurance to vibration tests after nitrogen PII, therefore being qualified for on-board application.

  1. Development of ion implanted gallium arsenide transistors

    NASA Technical Reports Server (NTRS)

    Hunsperger, R.; Baron, R.

    1972-01-01

    Techniques were developed for creating bipolar microwave transistors in GaAs by ion implantation doping. The electrical properties of doped layers produced by the implantation of the light ions Be, Mg, and S were studied. Be, Mg, and S are suitable for forming the relatively deep base-collector junction at low ion energies. The electrical characteristics of ion-implanted diodes of both the mesa and planar types were determined. Some n-p-n planar transistor structures were fabricated by implantation of Mg to form the base regions and Si to form the emitters. These devices were found to have reasonably good base-collector and emitter-base junctions, but the current gain beta was small. The low was attributable to radiative recombination in the base region, which was extremely wide.

  2. Optimization of the ion implantation process

    NASA Astrophysics Data System (ADS)

    Maczka, D.; Latuszynski, A.; Kuduk, R.; Partyka, J.

    This work is devoted to the optimization of the ion implantation process in the implanter Unimas of the Institute of Physics, Maria Curie-Sklodowska University, Lublin. The results obtained during several years of operation allow us to determine the optimal work parameters of the device [1-3].

  3. Effects of electrical conductivity of substrate materials on microstructure of diamond-like carbon films prepared by bipolar-type plasma based ion implantation

    NASA Astrophysics Data System (ADS)

    Nakao, S.; Sonoda, T.

    2013-03-01

    Diamond-like carbon (DLC) films are prepared by a bipolar-type plasma based ion implantation, and the structural differences between DLC films deposited on different electrical conductive substrates, i.e., conductive Si wafers and insulating glass plates are examined by Raman spectroscopy and x-ray photo emission spectroscopy (XPS). In the Raman measurements, graphite (G) and disorder (D) peaks are observed for both samples. However, the additional photo luminescence is overlapped on the spectra in the case of on-glass sample. To elucidate the structural difference, the intensity ratio of D to G peak (I(D)/I(G)), G peak position and full width at half maximum (FWHM) are obtained by curve fitting using Gaussian function and linear baseline. It is found that the I(D)/I(G) is lower, G peak position is higher and FWHM of G peak is narrower for on-glass sample than for on-Si sample. According to Robertson [1], lower I(D)/I(G) seems more sp3 C-C bonding in amount for on-glass sample. In contrast, higher G peak position and narrower FWHM of G peak suggest less sp3 C-C bonding in amount for on-glass sample. The results of XPS analysis with C1s spectra reveal that sp3 ratio, i.e., the intensity ratio of sp3/(sp3+sp2) is smaller for on-glass sample than for on-Si sample. The inconsistency of the trend between I(D)/I(G) and other parameters (G peak position and FWHM of G peak) might be caused by the overlap of photo luminescence signal on Raman spectrum as to on-glass sample. From these results, it is considered that sp3 C-C bonding is reduced in amount when using insulating substrate in comparison with conductive substrate.

  4. Infrared reflectance measurement of ion implanted silica

    SciTech Connect

    Magruder, R.H. III; Morgan, S.H.; Weeks, R.A.; Zuhr, R.

    1988-01-01

    Infrared reflectance spectra of silica glass implanted with Ti, Cr, Mn, Fe, and Bi to doses between 0.5 - 6 /times/10/sup 16/ cm/sup /minus/2/ have been measured from 5000 cm/sup /minus/1/ to 400 cm/sup /minus/1/ at room temperature. The ion energy of the implantation was 160 keV and the current was 10..mu..A. Alterations in reflectance of bands at 1125 and 481 cm/sup /minus/1/ in the spectrum of an unimplanted sample of the order of 20% are observed. A band attributed to non-bridging oxygen ions at /approximately/1015 cm/sup /minus/1/ is observed to increase in intensity with increasing dose for all species. The band at 1125 cm/sup /minus/1/ is observed to shift to lower wavenumber with implantation. Bands due to implanted ion-oxygen vibrations were not detected. The magnitudes of the effects on the existing bands were ion specific. This ion specificity is attributed to the differing chemical states of the implanted ions after implantation. 15 refs., 8 figs.

  5. Effects of phosphorus doping by plasma immersion ion implantation on the structural and optical characteristics of Zn{sub 0.85}Mg{sub 0.15}O thin films

    SciTech Connect

    Saha, S.; Nagar, S.; Chakrabarti, S.

    2014-08-11

    ZnMgO thin films deposited on 〈100〉 Si substrates by RF sputtering were annealed at 800, 900, and 1000 °C after phosphorus plasma immersion ion implantation. X-ray diffraction spectra confirmed the presence of 〈101{sup ¯}0〉 and 〈101{sup ¯}3〉 peaks for all the samples. However, in case of the annealed samples, the 〈0002〉 peak was also observed. Scanning electron microscopy images revealed the variation in surface morphology caused by phosphorus implantation. Implanted and non-implanted samples were compared to examine the effects of phosphorus implantation on the optical properties of ZnMgO. Optical characteristics were investigated by low-temperature (15 K) photoluminescence experiments. Inelastic exciton–exciton scattering and localized, and delocalized excitonic peaks appeared at 3.377, 3.42, and 3.45 eV, respectively, revealing the excitonic effect resulting from phosphorus implantation. This result is important because inelastic exciton–exciton scattering leads to nonlinear emission, which can improve the performance of many optoelectronic devices.

  6. Plasma-Ion Processing of Three-Dimensional Components

    SciTech Connect

    Yukimura, Ken; Wei Ronghua

    2004-12-01

    Plasma-based ion implantation and deposition (PBII and D) technology has been developed rapidly in the past decade. This technique is especially promising for modifying three-dimensional components. In PBII and D, plasma is generated in the entire processing chamber and then surrounds the components. When a train of negative voltage pulses are applied to the parts, ions are drawn to all the surfaces exposed to the plasma. At a high energy, ions are implanted to the surfaces, but at a low energy and with a proper precursor gases, ions are deposited to form a film. This technology has found applications in many areas including semiconductors, automotive, aerospace, energy and biomedical. This article reviews PBII and D fundamentals, describes features of various PBII and D systems and plasma sources, and discusses implantation and deposition techniques. The paper will also present application examples of this technology.

  7. Cd ion implantation in AlN

    NASA Astrophysics Data System (ADS)

    Miranda, S. M. C.; Franco, N.; Alves, E.; Lorenz, K.

    2012-10-01

    AlN thin films were implanted with cadmium, to fluences of 1 × 1013 and 8 × 1014 at/cm2. The implanted samples were annealed at 950 °C under flowing nitrogen. Although implantation damage in AlN is known to be extremely stable the crystal could be fully recovered at low fluences. At high fluences the implantation damage was only partially removed. Implantation defects cause an expansion of the c-lattice parameter. For the high fluence sample the lattice site location of the ions was studied by Rutherford Backscattering/Channelling Spectrometry. Cd ions are found to be incorporated in substitutional Al sites in the crystal and no significant diffusion is seen upon thermal annealing. The observed high solubility limit and site stability are prerequisite for using Cd as p-type dopant in AlN.

  8. Ion Implant Enabled 2x Lithography

    NASA Astrophysics Data System (ADS)

    Martin, Patrick M.; Godet, Ludovic; Cheung, Andrew; de Cock, Gael; Hatem, Chris

    2011-01-01

    Ion implantation has many applications in microelectronics beyond doping. The broad range of species available combined with the ability to precisely control dose, angle, and energy offers compelling advantages for use in precision material modification. The application to lithography has been reported elsewhere. Integrating ion implantation into the lithography process enables scaling the feature size requirements beyond the 15 nm node with a simplified double patterning sequence. In addition, ion implant may be used to remove line edge roughness, providing tremendous advantages to meet extreme lithography imaging requirements and provide additional device stability. We examine several species (e.g. Si, Ar, etc.) and the effect of energy and impact angle on several commercially available 193 nm immersion photoresists using a Varian VIISta® single wafer high current ion implanter. The treated photoresist will be evaluated for stability in an integrated double patterning application with ion implant used to freeze the primary image. We report on critical dimension impact, pattern integrity, optical property modification, and adhesion. We analyze the impact of line edge roughness improvement beyond the work of C. Struck including the power spectral distribution. TGA and FTIR Spectroscopy results for the implanted photoresist materials will also be included.

  9. Krypton ion implantation effect on selenium nanowires

    NASA Astrophysics Data System (ADS)

    Panchal, Suresh; Chauhan, R. P.

    2017-08-01

    Among the rapidly progressing interdisciplinary areas of physics, chemistry, material science etc. ion induced modifications of materials is one such evolving field. It has been realized in recent years that a material, in the form of an accelerated ion beam, embedded into a target specimen offers a most productive tool for transforming its properties in a controlled manner. In semiconductors particularly, where the transport behavior is determined by very small concentrations of certain impurities, implantation of ions may bring considerable changes. The present work is based on the study of the effect of krypton ion implantation on selenium nanowires. Selenium nanowires of diameter 80 nm were synthesized by template assisted electro deposition technique. Implantation of krypton ions was done at Inter University Accelerator Centre (IUAC), New Delhi, India. The effect of implantation on structural, electrical and optical properties of selenium nanowires was investigated. XRD analysis of pristine and implanted nanowires shows no shifting in the peak position but there is a variation in the relative intensity with fluence. UV-Visible spectroscopy shows the decrease in the optical band gap with fluence. PL spectra showed emission peak at higher wavelength. A substantial rise in the current was observed from I-V measurements, after implantation and with the increase in fluence. The increase in current conduction may be due to the increase in the current carriers.

  10. Ion implantations of oxide dispersion strengthened steels

    NASA Astrophysics Data System (ADS)

    Sojak, S.; Simeg Veternikova, J.; Slugen, V.; Petriska, M.; Stacho, M.

    2015-12-01

    This paper is focused on a study of radiation damage and thermal stability of high chromium oxide dispersion strengthened steel MA 956 (20% Cr), which belongs to the most perspective structural materials for the newest generation of nuclear reactors - Generation IV. The radiation damage was simulated by the implantation of hydrogen ions up to the depth of about 5 μm, which was performed at a linear accelerator owned by Slovak University of Technology. The ODS steel MA 956 was available for study in as-received state after different thermal treatments as well as in ions implanted state. Energy of the hydrogen ions chosen for the implantation was 800 keV and the implantation fluence of 6.24 × 1017 ions/cm2. The investigated specimens were measured by non-destructive technique Positron Annihilation Lifetime Spectroscopy in order to study the defect behavior after different thermal treatments in the as-received state and after the hydrogen ions implantation. Although, different resistance to defect production was observed in individual specimens of MA 956 during the irradiation, all implanted specimens contain larger defects than the ones in as-received state.

  11. Molecular ion sources for low energy semiconductor ion implantation (invited).

    PubMed

    Hershcovitch, A; Gushenets, V I; Seleznev, D N; Bugaev, A S; Dugin, S; Oks, E M; Kulevoy, T V; Alexeyenko, O; Kozlov, A; Kropachev, G N; Kuibeda, R P; Minaev, S; Vizir, A; Yushkov, G Yu

    2016-02-01

    Smaller semiconductors require shallow, low energy ion implantation, resulting space charge effects, which reduced beam currents and production rates. To increase production rates, molecular ions are used. Boron and phosphorous (or arsenic) implantation is needed for P-type and N-type semiconductors, respectively. Carborane, which is the most stable molecular boron ion leaves unacceptable carbon residue on extraction grids. A self-cleaning carborane acid compound (C4H12B10O4) was synthesized and utilized in the ITEP Bernas ion source resulting in large carborane ion output, without carbon residue. Pure gaseous processes are desired to enable rapid switch among ion species. Molecular phosphorous was generated by introducing phosphine in dissociators via 4PH3 = P4 + 6H2; generated molecular phosphorous in a pure gaseous process was then injected into the HCEI Calutron-Bernas ion source, from which P4(+) ion beams were extracted. Results from devices and some additional concepts are described.

  12. Molecular ion sources for low energy semiconductor ion implantation (invited)

    NASA Astrophysics Data System (ADS)

    Hershcovitch, A.; Gushenets, V. I.; Seleznev, D. N.; Bugaev, A. S.; Dugin, S.; Oks, E. M.; Kulevoy, T. V.; Alexeyenko, O.; Kozlov, A.; Kropachev, G. N.; Kuibeda, R. P.; Minaev, S.; Vizir, A.; Yushkov, G. Yu.

    2016-02-01

    Smaller semiconductors require shallow, low energy ion implantation, resulting space charge effects, which reduced beam currents and production rates. To increase production rates, molecular ions are used. Boron and phosphorous (or arsenic) implantation is needed for P-type and N-type semiconductors, respectively. Carborane, which is the most stable molecular boron ion leaves unacceptable carbon residue on extraction grids. A self-cleaning carborane acid compound (C4H12B10O4) was synthesized and utilized in the ITEP Bernas ion source resulting in large carborane ion output, without carbon residue. Pure gaseous processes are desired to enable rapid switch among ion species. Molecular phosphorous was generated by introducing phosphine in dissociators via 4PH3 = P4 + 6H2; generated molecular phosphorous in a pure gaseous process was then injected into the HCEI Calutron-Bernas ion source, from which P4+ ion beams were extracted. Results from devices and some additional concepts are described.

  13. High-intensity laser for Ta and Ag implantation into different substrates for plasma diagnostics

    NASA Astrophysics Data System (ADS)

    Cutroneo, M.; Mackova, A.; Malinsky, P.; Matousek, J.; Torrisi, L.; Ullschmied, J.

    2015-07-01

    High-intensity lasers generating non-equilibrium plasma, can be employed to accelerate ions in the keV-MeV region, useful for many applications. In the present work, we performed study of ion implantation into different substrates by using a high-intensity laser at the PALS laboratory in Prague. Multi-energy ions generated by plasma from Ta and Ag targets were implanted into polyethylene and metallic substrates (Al, Ti) at energies of tens of keV per charge state. The ion emission was monitored online using time-of-flight detectors and electromagnetic deflection systems. Rutherford Backscattering Spectrometry (RBS) was used to characterise the elemental composition in the implanted substrates by ion plasma emission and to provide the implanted ion depth profiling. These last measurements enable offline plasma characterisation and provide information on the useful potentiality of multi-ion species and multi-energy ion implantation into different substrates. XPS analysis gives information on the chemical bonds and their modifications in the first superficial implanted layers. The depth distributions of implanted Ta and Ag ions were compared with the theoretical ones achieved by using the SRIM-2012 simulation code.

  14. Gold ion implantation into alumina using an "inverted ion source" configuration

    NASA Astrophysics Data System (ADS)

    Salvadori, M. C.; Teixeira, F. S.; Sgubin, L. G.; Araujo, W. W. R.; Spirin, R. E.; Cattani, M.; Oks, E. M.; Brown, I. G.

    2014-02-01

    We describe an approach to ion implantation in which the plasma and its electronics are held at ground potential and the ion beam is injected into a space held at high negative potential, allowing considerable savings both economically and technologically. We used an "inverted ion implanter" of this kind to carry out implantation of gold into alumina, with Au ion energy 40 keV and dose (3-9) × 1016 cm-2. Resistivity was measured in situ as a function of dose and compared with predictions of a model based on percolation theory, in which electron transport in the composite is explained by conduction through a random resistor network formed by Au nanoparticles. Excellent agreement is found between the experimental results and the theory.

  15. Ion implantation in crystalline and amorphous materials

    NASA Astrophysics Data System (ADS)

    Tasch, Al F.

    1998-05-01

    Ion implantation continues to be the selective doping technique of choice in silicon integrated circuit (IC) manufacturing, and its applications continue to grow in doping, damage gettering, and process simplification. However, in both technology and manufacturing equipment development there is a rapidly increasing need to understand in detail the dependence of implanted impurity profiles and implant-induced damage profiles in silicon on all key implant parameters. These reasons include largely reduced thermal budgets in IC processing, heavy emphasis on control of equipment and process costs, and the need for rigid manufacturing control. Towards this end, accurate, comprehensive, and computationally efficient models for ion implanted profiles (impurity and damage) in silicon are indispensable. These models greatly facilitate more timely technology development and implementation in manufacturing, improved manufacturing process control; and the development of new ion implantation tools can be executed more efficiently. This talk describes ion implant models and simulators developed in the ion implant modeling research/education project at the University of Texas at Austin. Physically based models for ion implantation into single-crystal Si have been developed for the commonly used implant species B, BF(2), As, P, and Si for the most commonly used implant energy ranges. These models have explicit dependence on the major implant parameters (energy, dose, tilt angle and rotation angle). In addition, the models have been extensively verified by the vast amount of experimental data which has been obtained in the experimental part of this project. The models have been extended down to ultra-low implant energies (<2keV) by removing two of the three major limitations of the binary collision approximation (bca) at ultra-low energies and overcoming part of the third limitation. At very high energies where electronic stopping dominates the energy loss, an electronic stopping

  16. Ion implantation of silicon nitride ball bearings

    SciTech Connect

    Williams, J.M.; Miner, J.R.

    1996-09-01

    Hypothesis for ion implantation effect was that stress concentrations reflected into the bulk due to topography such as polishing imperfections, texture in the race, or transferred material, might be reduced due to surface amorphization. 42 control samples were tested to an intended runout period of 60 h. Six ion implanted balls were tested to an extended period of 150 h. Accelerated testing was done in a V groove so that wear was on two narrow wear tracks. Rutherford backscattering, XRPS, profilometry, optical microscopy, nanoindentation hardness, and white light interferometry were used. The balls were implanted with 150-keV C ions at fluence 1.1x10{sup 17}/cm{sup 2}. The samples had preexisting surface defects (C-cracks), so the failure rate of the control group was unacceptable. None of the ion-implanted samples failed in 150 h of testing. Probability of randomly selecting 6 samples from the control group that would perform this well is about 5%, so there is good probability that ion implantation improved performance. Possible reasons are discussed. Wear tracks, microstructure, and impurity content were studied in possible relation to C-cracks.

  17. Ion implanted Bragg{endash}Fresnel lens

    SciTech Connect

    Souvorov, A.; Snigirev, A.; Snigireva, I.; Aristova, E.

    1996-05-01

    We have investigated the feasibility of widening the bandpath of the Bragg{endash}Fresnel optical element through the use of ion implantation. The focusing properties of Bragg{endash}Fresnel lenses (BFLs) were studied as a function of the implantation dose and energy. An enhancement of the focus intensity of up to 15{percent} was found, which is less than expected. Due to the complicated scattering of the low energy ions inside the micrometer- and submicrometer-sized crystal features that make up the BFL relief, the implantation technology destroys the peripheral zones of the BFL more than it increases the intensity in the focus. Nevertheless we believe that high energy implantation can be successfully used to modify the BFL reflectivity, especially in the case of nearly backscattering reflection. {copyright} {ital 1996 American Institute of Physics.}

  18. More-reliable SOS ion implantations

    NASA Technical Reports Server (NTRS)

    Woo, D. S.

    1980-01-01

    Conducting layer prevents static charges from accumulating during implantation of silicon-on-sapphire MOS structures. Either thick conducting film or thinner film transparent to ions is deposited prior to implantation, and gaps are etched in regions to be doped. Grounding path eliminates charge flow that damages film or cracks sapphire wafer. Prevention of charge buildup by simultaneously exposing structure to opposite charges requires equipment modifications less practical and more expensive than deposition of conducting layer.

  19. Enhanced patterning by tilted ion implantation

    NASA Astrophysics Data System (ADS)

    Kim, Sang Wan; Zheng, Peng; Kato, Kimihiko; Rubin, Leonard; Liu, Tsu-Jae King

    2016-03-01

    Tilted ion implantation (TII) is proposed as a lower-cost alternative to self-aligned double patterning (SADP) for pitch halving. This new approach is based on an enhancement in etch rate of a hard-mask layer by implant-induced damage. Ar+ implantation into a thin layer of silicon dioxide (SiO2) is shown to enhance its etch rate in dilute hydrofluoric acid (HF) solution, by up to 9× for an implant dose of 3×1014 cm-2. The formation of sub-lithographic features defined by masked tilted Ar+ implantation into a SiO2 hard-mask layer is experimentally demonstrated. Features with sizes as small as ~21 nm, self-aligned to the lithographically patterned mask, are achieved. As compared with SADP, enhanced patterning by TII requires far fewer and lower-cost process steps and hence is expected to be much more cost-effective.

  20. Negative-ion plasma sources

    NASA Astrophysics Data System (ADS)

    Sheehan, D. P.; Rynn, N.

    1988-08-01

    Three designs for negative-ion plasma sources are described. Two sources utilize metal hexafluorides such as SF6 and WF6 to scavenge electrons from electron-ion plasmas and the third relies upon surface ionization of alkali halide salts on heated alumina and zirconia. SF6 introduced into electron-ion plasmas yielded negative-ion plasma densities of 10 to the 10th/cu cm with low residual electron densities. On alumina, plasma densities of 10 to the 9th/cu cm were obtained for CsCl, CsI, and KI and 10 to the 9th/cu cm for KCl. On zirconia 10 to the 10th/cu cm densities were obtained for CsCl. For alkali halide sources, electron densities of less than about 10 to the -4th have been achieved.

  1. Diffusion mechanism and the thermal stability of fluorine ions in GaN after ion implantation

    SciTech Connect

    Wang, M. J.; Yuan, L.; Chen, K. J.; Xu, F. J.; Shen, B.

    2009-04-15

    The diffusion mechanisms of fluorine ions in GaN are investigated by means of time-of-flight secondary ion mass spectrometry. Instead of incorporating fluorine ions close to the sample surface by fluorine plasma treatment, fluorine ion implantation with an energy of 180 keV is utilized to implant fluorine ions deep into the GaN bulk, preventing the surface effects from affecting the data analysis. It is found that the diffusion of fluorine ions in GaN is a dynamic process featuring an initial out-diffusion followed by in- diffusion and the final stabilization. A vacancy-assisted diffusion model is proposed to account for the experimental observations, which is also consistent with results on molecular dynamic simulation. Fluorine ions tend to occupy Ga vacancies induced by ion implantation and diffuse to vacancy rich regions. The number of continuous vacancy chains can be significantly reduced by a dynamic thermal annealing process. As a result, strong local confinement and stabilization of fluorine ions can be obtained in GaN crystal, suggesting excellent thermal stability of fluorine ions for device applications.

  2. Effects of bias voltage on the corrosion resistance of titanium nitride thin films fabricated by dynamic plasma immersion ion implantation-deposition

    NASA Astrophysics Data System (ADS)

    Tian, Xiubo; Fu, Ricky K. Y.; Chu, Paul K.

    2002-01-01

    Dynamic plasma-based thin-film deposition incorporating ion mixing and plasma immersion is an effective technique to synthesize nitride-based hard films. We have fabricated TiN films using a filtered titanium vacuum arc in a nitrogen plasma environment. A pulsed high voltage is applied to the target for a short time when the metallic arc is fired to attain simultaneous plasma deposition and ion mixing. We investigate the dependence of the corrosion resistance and interfacial structure of the treated samples on the applied voltage. Our Auger results reveal an oxygen-rich surface film due to the non-ultra-high-vacuum conditions and high affinity of oxygen to titanium. The corrosion current is reduced by two orders of magnitude comparing the sample processed at 8 kV to the untreated sample, but the 23 kV sample unexpectedly shows worse results. The pitting potential diminishes substantially although the corrosion current is similar to that observed in the 8 kV sample. The polarization test data are consistent with our scanning electron microscopy observation, corroborating the difference in the pitting distribution and appearance. This anomalous behavior is believed to be due to the change in the chemical composition as a result of high-energy ion bombardment.

  3. Surface modification by ion implantation and ion beam mixing

    NASA Astrophysics Data System (ADS)

    Rivière, J. P.

    1992-05-01

    After its successful applications in the semiconductor industry, ion implantation is being employed for other technical applications. The main process in ion implantation is the introduction of additive elements to change the composition and properties of the surface region of a material. We present results demonstrating the important improvement of the wear resistance and friction in a NiTi alloy implanted with nitrogen. The formation of hard TiN precipitates embedded in an amorphous layer is responsible for such modifications. The generation of many atomic displacements in collision cascades during implantation can be also employed as a modification process itself. For instance, the chemical disordering in an implanted Fe60Al40 alloy induces a para- to ferromagnetic transition. The formation of an amorphous surface alloy by ion irradiation at a temperature of 15 K has been shown in Ni50Al50 by in situ RBS, channelling and TEM. The new method of dynamic ion mixing (DIM) combines ion bombardment with simultaneous material deposition and allows thicker adherent coatings to be built up, this is shown for both metallic Cu50Ni50 and ceramic TiB2 coatings. Recent results demonstrating a significant increase in fatigue lifetime of a coated 316 L stainless steel are also reported and discussed.

  4. Single Ion Implantation and Deterministic Doping

    SciTech Connect

    Schenkel, Thomas

    2010-06-11

    The presence of single atoms, e.g. dopant atoms, in sub-100 nm scale electronic devices can affect the device characteristics, such as the threshold voltage of transistors, or the sub-threshold currents. Fluctuations of the number of dopant atoms thus poses a complication for transistor scaling. In a complementary view, new opportunities emerge when novel functionality can be implemented in devices deterministically doped with single atoms. The grand price of the latter might be a large scale quantum computer, where quantum bits (qubits) are encoded e.g. in the spin states of electrons and nuclei of single dopant atoms in silicon, or in color centers in diamond. Both the possible detrimental effects of dopant fluctuations and single atom device ideas motivate the development of reliable single atom doping techniques which are the subject of this chapter. Single atom doping can be approached with top down and bottom up techniques. Top down refers to the placement of dopant atoms into a more or less structured matrix environment, like a transistor in silicon. Bottom up refers to approaches to introduce single dopant atoms during the growth of the host matrix e.g. by directed self-assembly and scanning probe assisted lithography. Bottom up approaches are discussed in Chapter XYZ. Since the late 1960's, ion implantation has been a widely used technique to introduce dopant atoms into silicon and other materials in order to modify their electronic properties. It works particularly well in silicon since the damage to the crystal lattice that is induced by ion implantation can be repaired by thermal annealing. In addition, the introduced dopant atoms can be incorporated with high efficiency into lattice position in the silicon host crystal which makes them electrically active. This is not the case for e.g. diamond, which makes ion implantation doping to engineer the electrical properties of diamond, especially for n-type doping much harder then for silicon. Ion

  5. Insulator-metal transition induced by ion implantation in LiF

    NASA Astrophysics Data System (ADS)

    Davenas, J.; Dupuy, C.

    1981-05-01

    The modification of the optical properties of LiF crystals implanted with alkali ions has been studied according to the implantation temperature. The implanted ions have a tendency to cluster in crystal implanted at room temperature, and this precipitation process continues during thermal annealings. A characteristic absorption band may be associated with the excitation of the plasma oscillation of the metallic clusters formed by the precipitation of the implanted ions. The absorption spectrum of the room temperature implanted crystals is then characteristic of a metallic granular thin layer. At low temperature this precipitation process is inhibited and the absorption spectrum does not show any formation of a colloidal band associated with the implanted ions. Anomalous absorption appears for a critical concentration of implanted alkali ions, which is about 5%. The absorption spectrum is typical of the case of a continuous metallic thin layer. The transition to a metallic state has been confirmed by electrical conductivity measurements and by the chemical reactivity of the implanted layer with the oxygen, of the air. The continuous thin layer which is induced by the implantation of alkali ions at low temperature is metastable and its transformation into the granular layer may be observed near room temperature. The optical absorption spectra of the granular or continuous implanted layer may be interpreted using the Maxwell-Garnett theory.

  6. Metal ion implantation for large scale surface modification

    SciTech Connect

    Brown, I.G.

    1992-10-01

    Intense energetic beams of metal ions can be produced by using a metal vapor vacuum arc as the plasma discharge from which the ion beam is formed. We have developed a number of ion sources of this kind and have built a metal ion implantation facility which can produce repetitively pulsed ion beams with mean ion energy up to several hundred key, pulsed beam current of more than an ampere, and time averaged current of several tens of milliamperes delivered onto a downstream target. We've also done some preliminary work on scaling up this technology to very large size. For example, a 50-cm diameter (2000 cm[sup 2]) set of beam formation electrodes was used to produce a pulsed titanium beam with ion current over 7 amperes at a mean ion energy of 100 key. Separately, a dc embodiment has been used to produce a dc titanium ion beam with current over 600 mA, power supply limited in this work, and up to 6 amperes of dc plasma ion current was maintained for over an hour. In a related program we've developed a plasma immersion method for applying thin metallic and compound films in which the added species is atomically mixed to the substrate. By adding a gas flow to the process, well-bonded compound films can also be formed; metallic films and multilayers as well as oxides and nitrides with mixed transition zones some hundreds of angstroms thick have been synthesized. Here we outline these parallel metal-plasma-based research programs and describe the hardware that we've developed and some of the surface modification research that we've done with it.

  7. Hybrid quantum circuit with implanted erbium ions

    SciTech Connect

    Probst, S.; Rotzinger, H.; Tkalčec, A.; Kukharchyk, N.; Wieck, A. D.; Wünsch, S.; Siegel, M.; Ustinov, A. V.; Bushev, P. A.

    2014-10-20

    We report on hybrid circuit quantum electrodynamics experiments with focused ion beam implanted Er{sup 3+} ions in Y{sub 2}SiO{sub 5} coupled to an array of superconducting lumped element microwave resonators. The Y{sub 2}SiO{sub 5} crystal is divided into several areas with distinct erbium doping concentrations, each coupled to a separate resonator. The coupling strength is varied from 5 MHz to 18.7 MHz, while the linewidth ranges between 50 MHz and 130 MHz. We confirm the paramagnetic properties of the implanted spin ensemble by evaluating the temperature dependence of the coupling. The efficiency of the implantation process is analyzed and the results are compared to a bulk doped Er:Y{sub 2}SiO{sub 5} sample. We demonstrate the integration of these engineered erbium spin ensembles with superconducting circuits.

  8. 6Li + ion implantation into polystyrene

    NASA Astrophysics Data System (ADS)

    Soares, M. R. F.; Alegaonkar, P.; Behar, M.; Fink, D.; Müller, M.

    2004-06-01

    100 keV 6Li + ions were implanted into polystyrene at fluences of 1 × 10 13 to 1 × 10 14 cm -2, and their depth distributions were determined by means of the neutron depth profiling technique. In no case the projectile ions are found to come to rest according to their predicted implantation profiles. Instead, they always undergo considerable migration. During the irradiation process this motion is influenced by the radiation damage, and during the subsequent annealing steps one deals with thermal diffusion. The implant redistribution is always found to be governed strongly by the self-created damage, insofar as both electronic and nuclear defects in the polymer act as trapping centers.

  9. Implantation of sodium ions into germanium

    SciTech Connect

    Korol', V. M.; Kudriavtsev, Yu.

    2012-02-15

    The donor properties of Na atoms introduced by ion implantation into p-Ge with the resistivity 20-40 {Omega} cm are established for the first time. Na profiles implanted into Ge (the energies 70 and 77 keV and the doses (0.8, 3, 30) Multiplication-Sign 10{sup 14} cm{sup -2}) are studied. The doses and annealing temperatures at which the thermoprobe detects n-type conductivity on the sample surface are established. After implantation, the profiles exhibit an extended tail. The depth of the concentration maximum is in good agreement with the calculated mean projected range of Na ions R{sub p}. Annealing for 30 min at temperatures of 250-700 Degree-Sign C brings about a redistribution of Na atoms with the formation of segregation peaks at a depth, which is dependent on the ion dose, and is accompanied by the diffusion of Na atoms to the surface with subsequent evaporation. After annealing at 700 Degree-Sign C less than 7% of the implanted ions remain in the matrix. The shape of the profile tail portions measured after annealing at temperatures 300-400 Degree-Sign C is indicative of the diffusion of a small fraction of Na atoms into the depth of the sample.

  10. Lattice damage during ion implantation of semiconductors

    SciTech Connect

    Haynes, T.E.

    1993-08-01

    The temperature dependence of the lattice damage created during ion implantation of Si, Ge, Si-Ge alloys, and various III-V compounds is reviewed and interpreted in terms of a transition between two different damage formation mechanisms. Implications of this transition for control of damage, annealing, and electrical activation are discussed, particularly in GaAs.

  11. Energetic ions in ITER plasmas

    SciTech Connect

    Pinches, S. D.; Chapman, I. T.; Sharapov, S. E.; Lauber, Ph. W.; Oliver, H. J. C.; Shinohara, K.; Tani, K.

    2015-02-15

    This paper discusses the behaviour and consequences of the expected populations of energetic ions in ITER plasmas. It begins with a careful analytic and numerical consideration of the stability of Alfvén Eigenmodes in the ITER 15 MA baseline scenario. The stability threshold is determined by balancing the energetic ion drive against the dominant damping mechanisms and it is found that only in the outer half of the plasma (r/a>0.5) can the fast ions overcome the thermal ion Landau damping. This is in spite of the reduced numbers of alpha-particles and beam ions in this region but means that any Alfvén Eigenmode-induced redistribution is not expected to influence the fusion burn process. The influence of energetic ions upon the main global MHD phenomena expected in ITER's primary operating scenarios, including sawteeth, neoclassical tearing modes and Resistive Wall Modes, is also reviewed. Fast ion losses due to the non-axisymmetric fields arising from the finite number of toroidal field coils, the inclusion of ferromagnetic inserts, the presence of test blanket modules containing ferromagnetic material, and the fields created by the Edge Localised Mode (ELM) control coils in ITER are discussed. The greatest losses and associated heat loads onto the plasma facing components arise due to the use of the ELM control coils and come from neutral beam ions that are ionised in the plasma edge.

  12. Ion sources for energy extremes of ion implantation (invited)

    SciTech Connect

    Hershcovitch, A.; Johnson, B. M.; Batalin, V. A.; Kropachev, G. N.; Kuibeda, R. P.; Kulevoy, T. V.; Kolomiets, A. A.; Pershin, V. I.; Petrenko, S. V.; Rudskoy, I.; Seleznev, D. N.; Bugaev, A. S.; Gushenets, V. I.; Litovko, I. V.; Oks, E. M.; Yushkov, G. Yu.; Masunov, E. S.; Polozov, S. M.; Poole, H. J; Storozhenko, P. A.

    2008-02-15

    For the past four years a joint research and development effort designed to develop steady state, intense ion sources has been in progress with the ultimate goal to develop ion sources and techniques that meet the two energy extreme range needs of meV and hundreads of eV ion implanters. This endeavor has already resulted in record steady state output currents of high charge state of antimony and phosphorus ions: P{sup 2+} [8.6 pmA (particle milliampere)], P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+}Sb{sup 4+}, Sb{sup 5+}, and Sb{sup 6+} respectively. For low energy ion implantation, our efforts involve molecular ions and a novel plasmaless/gasless deceleration method. To date, 1 emA (electrical milliampere) of positive decaborane ions was extracted at 10 keV and smaller currents of negative decaborane ions were also extracted. Additionally, boron current fraction of over 70% was extracted from a Bernas-Calutron ion source, which represents a factor of 3.5 improvement over currently employed ion sources.

  13. ION SOURCES FOR ENERGY EXTREMES OF ION IMPLANTATION.

    SciTech Connect

    HERSCHCOVITCH,A.; JOHNSON, B.M.; BATALIN, V.A.; KROPACHEV, G.N.; KUIBEDA, R.P.; KULEVOY, T.V.; KOLOMIETS, A.A.; PERSHIN, V.I.; PETRENKO, S.V.; RUDSKOY, I.; SELEZNEV, D.N.; BUGAEV, A.S.; GUSHENETS, V.I.; LITOVKO, I.V.; OKS, E.M.; YUSHKOV, G. YU.; MASEUNOV, E.S.; POLOZOV, S.M.; POOLE, H.J.; STOROZHENKO, P.A.; SVAROVSKI, YA.

    2007-08-26

    For the past four years a joint research and development effort designed to develop steady state, intense ion sources has been in progress with the ultimate goal to develop ion sources and techniques, which meet the two energy extreme range needs of mega-electron-volt and 100's of electron-volt ion implanters. This endeavor has already resulted in record steady state output currents of high charge state of Antimony and Phosphorous ions: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb{sup 4+}, Sb{sup 5+}, and Sb{sup 6+} respectively. For low energy ion implantation our efforts involve molecular ions and a novel plasmaless/gasless deceleration method. To date, 1 emA of positive Decaborane ions were extracted at 10 keV and smaller currents of negative Decaborane ions were also extracted. Additionally, Boron current fraction of over 70% was extracted from a Bemas-Calutron ion source, which represents a factor of 3.5 improvement over currently employed ion sources.

  14. The MEVVA ion source for high current metal ion implantation

    NASA Astrophysics Data System (ADS)

    Brown, Ian; Washburn, Jack

    The MEVVA (Metal Vapor Vacuum Arc) ion source is a new kind of source which can produce high current beams of metal ions. Beams of a wide range of elements have been produced, spanning the periodic table from lithium up to and including uranium. The source extraction voltage is up to 60 kV, and we are increasing this up to 120 kV. A total ion beam current of over 1 A has been extracted from the present embodiment of the concept, and this is not an inherent limit. The ion charge state distribution varies with cathode material and are current, and beams like Li +, Co +.2+.3+ and U 3+.4+.5+.6+ for example, are typical; thus the implantation energy can be up to several hundred kV without additional acceleration. The ion source has potential applications for ion implantation and ion beam mixing for achievement of improved corrosion resistance or wear resistance in metals or surface modification of ceramic materials and semiconductors. Here we outline the source and its performance, and describe some very preliminary implantation work using this source.

  15. Enhanced life ion source for germanium and carbon ion implantation

    SciTech Connect

    Hsieh, Tseh-Jen; Colvin, Neil; Kondratenko, Serguei

    2012-11-06

    Germanium and carbon ions represent a significant portion of total ion implantation steps in the process flow. Very often ion source materials that used to produce ions are chemically aggressive, especially at higher temperatures, and result in fast ion source performance degradation and a very limited lifetime [B.S. Freer, et. al., 2002 14th Intl. Conf. on Ion Implantation Technology Proc, IEEE Conf. Proc., p. 420 (2003)]. GeF{sub 4} and CO{sub 2} are commonly used to generate germanium and carbon beams. In the case of GeF{sub 4} controlling the tungsten deposition due to the de-composition of WF{sub 6} (halogen cycle) is critical to ion source life. With CO{sub 2}, the materials oxidation and carbon deposition must be controlled as both will affect cathode thermionic emission and anti-cathode (repeller) efficiencies due to the formation of volatile metal oxides. The improved ion source design Extended Life Source 3 (Eterna ELS3) together with its proprietary co-gas material implementation has demonstrated >300 hours of stable continuous operation when using carbon and germanium ion beams. Optimizing cogas chemistries retard the cathode erosion rate for germanium and carbon minimizes the adverse effects of oxygen when reducing gas is introduced for carbon. The proprietary combination of hardware and co-gas has improved source stability and the results of the hardware and co-gas development are discussed.

  16. Ion implantation of solar cell junctions without mass analysis

    NASA Technical Reports Server (NTRS)

    Fitzgerald, D.; Tonn, D. G.

    1981-01-01

    This paper is a summary of an investigation to determine the feasibility of producing solar cells by means of ion implantation without the use of mass analysis. Ion implants were performed using molecular and atomic phosphorus produced by the vaporization of solid red phosphorus and ionized in an electron bombardment source. Solar cell junctions were ion implanted by mass analysis of individual molecular species and by direct unanalyzed implants from the ion source. The implant dose ranged from 10 to the 14th to 10 to the 16th atoms/sq cm and the energy per implanted atom ranged from 5 KeV to 40 KeV in this study.

  17. Rhenium ion beam for implantation into semiconductors

    SciTech Connect

    Kulevoy, T. V.; Seleznev, D. N.; Alyoshin, M. E.; Kraevsky, S. V.; Yakushin, P. E.; Khoroshilov, V. V.; Gerasimenko, N. N.; Smirnov, D. I.; Fedorov, P. A.; Temirov, A. A.

    2012-02-15

    At the ion source test bench in Institute for Theoretical and Experimental Physics the program of ion source development for semiconductor industry is in progress. In framework of the program the Metal Vapor Vacuum Arc ion source for germanium and rhenium ion beam generation was developed and investigated. It was shown that at special conditions of ion beam implantation it is possible to fabricate not only homogenous layers of rhenium silicides solid solutions but also clusters of this compound with properties of quantum dots. At the present moment the compound is very interesting for semiconductor industry, especially for nanoelectronics and nanophotonics, but there is no very developed technology for production of nanostructures (for example quantum sized structures) with required parameters. The results of materials synthesis and exploration are presented.

  18. Method for ion implantation induced embedded particle formation via reduction

    DOEpatents

    Hampikian, Janet M; Hunt, Eden M

    2001-01-01

    A method for ion implantation induced embedded particle formation via reduction with the steps of ion implantation with an ion/element that will chemically reduce the chosen substrate material, implantation of the ion/element to a sufficient concentration and at a sufficient energy for particle formation, and control of the temperature of the substrate during implantation. A preferred embodiment includes the formation of particles which are nano-dimensional (<100 m-n in size). The phase of the particles may be affected by control of the substrate temperature during and/or after the ion implantation process.

  19. Application of ion implantation in tooling industry

    NASA Astrophysics Data System (ADS)

    Straede, Christen A.

    1996-06-01

    In papers published during the last half of the 1980s it is often stated that the application of ion beams to non-semiconductor purposes seems ready for full-scale industrial exploitation. However, progress with respect to commercialisation of ion implantation has been slower than predicted, although the process is quite clearly building up niche markets, especially in the tooling industry. It is the main purpose of this paper to discuss the implementation of the process in the tooling market, and to describe strategies used to ensure its success. The basic idea has been to find niches where ion implantation out-performs other processes both technically and in prices. For instance, it has been clearly realised that one should avoid competing with physical vapour deposition or other coating techniques in market areas where they perform excellently, and instead find niches where the advantages of the ion implantation technique can be fully utilised. The paper will present typical case stories in order to illustrate market niches where the technique has its greatest successes and potential.

  20. Production of Endohedral Fullerenes by Ion Implantation

    SciTech Connect

    Diener, M.D.; Alford, J. M.; Mirzadeh, S.

    2007-05-31

    The empty interior cavity of fullerenes has long been touted for containment of radionuclides during in vivo transport, during radioimmunotherapy (RIT) and radioimaging for example. As the chemistry required to open a hole in fullerene is complex and exceedingly unlikely to occur in vivo, and conformational stability of the fullerene cage is absolute, atoms trapped within fullerenes can only be released during extremely energetic events. Encapsulating radionuclides in fullerenes could therefore potentially eliminate undesired toxicity resulting from leakage and catabolism of radionuclides administered with other techniques. At the start of this project however, methods for production of transition metal and p-electron metal endohedral fullerenes were completely unknown, and only one method for production of endohedral radiofullerenes was known. They therefore investigated three different methods for the production of therapeutically useful endohedral metallofullerenes: (1) implantation of ions using the high intensity ion beam at the Oak Ridge National Laboratory (ORNL) Surface Modification and Characterization Research Center (SMAC) and fullerenes as the target; (2) implantation of ions using the recoil energy following alpha decay; and (3) implantation of ions using the recoil energy following neutron capture, using ORNL's High Flux Isotope Reactor (HFIR) as a thermal neutron source. While they were unable to obtain evidence of successful implantation using the ion beam at SMAC, recoil following alpha decay and neutron capture were both found to be economically viable methods for the production of therapeutically useful radiofullerenes. In this report, the procedures for preparing fullerenes containing the isotopes {sup 212}Pb, {sup 212}Bi, {sup 213}Bi, and {sup 177}Lu are described. None of these endohedral fullerenes had ever previously been prepared, and all of these radioisotopes are actively under investigation for RIT. Additionally, the chemistry for

  1. Molecular ion sources for low energy semiconductor ion implantation (invited)

    SciTech Connect

    Hershcovitch, A.; Gushenets, V. I.; Bugaev, A. S.; Oks, E. M.; Vizir, A.; Yushkov, G. Yu.; Seleznev, D. N.; Kulevoy, T. V.; Kozlov, A.; Kropachev, G. N.; Kuibeda, R. P.; Minaev, S.; Dugin, S.; Alexeyenko, O.

    2016-02-15

    Smaller semiconductors require shallow, low energy ion implantation, resulting space charge effects, which reduced beam currents and production rates. To increase production rates, molecular ions are used. Boron and phosphorous (or arsenic) implantation is needed for P-type and N-type semiconductors, respectively. Carborane, which is the most stable molecular boron ion leaves unacceptable carbon residue on extraction grids. A self-cleaning carborane acid compound (C{sub 4}H{sub 12}B{sub 10}O{sub 4}) was synthesized and utilized in the ITEP Bernas ion source resulting in large carborane ion output, without carbon residue. Pure gaseous processes are desired to enable rapid switch among ion species. Molecular phosphorous was generated by introducing phosphine in dissociators via 4PH{sub 3} = P{sub 4} + 6H{sub 2}; generated molecular phosphorous in a pure gaseous process was then injected into the HCEI Calutron-Bernas ion source, from which P{sub 4}{sup +} ion beams were extracted. Results from devices and some additional concepts are described.

  2. High current metal ion implantation facility

    SciTech Connect

    Oztarhan, A.; Brown, I.G.; Evans, P.; Watt, G.; Bakkaloglu, C.; Eltas, A.S.; Oks, E.

    1998-12-31

    A vacuum arc ion source based metal ion implantation facility has been established at Dokuz Eylul University, Izmir, Turkey and a surface modification research and development program is underway. The system is similar to the one in Lawrence Berkeley Laboratory which was first built and developed by Brown et al. The broad-beam ion source is repetitively pulsed at rates up to {approximately}10 pulses per second (can be increased to 50 pulses per second) and the extracted ion beam current can be up to {approximately}1 Amp. peak or {approximately}10 mA time averaged. The ion source extraction voltage was increased to 60 kV corresponding to mean beam energies of up to 150 keV or more because of the ion charge state multiplicity (extraction voltage can be increased to 100 kV if desired). Commissioning of the facility is in progress. Initial emphasis of the R and D programs that will be carried out will be in forming tribologically enhanced materials for industrial applications. In this paper they describe the design and operation of the implanter, summarize the preliminary performance parameters that have been obtained, and outline some of the programs they anticipate doing.

  3. Accelerating degradation rate of pure iron by zinc ion implantation.

    PubMed

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-12-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications.

  4. Accelerating degradation rate of pure iron by zinc ion implantation

    PubMed Central

    Huang, Tao; Zheng, Yufeng; Han, Yong

    2016-01-01

    Pure iron has been considered as a promising candidate for biodegradable implant applications. However, a faster degradation rate of pure iron is needed to meet the clinical requirement. In this work, metal vapor vacuum arc technology was adopted to implant zinc ions into the surface of pure iron. Results showed that the implantation depth of zinc ions was about 60 nm. The degradation rate of pure iron was found to be accelerated after zinc ion implantation. The cytotoxicity tests revealed that the implanted zinc ions brought a slight increase on cytotoxicity of the tested cells. In terms of hemocompatibility, the hemolysis of zinc ion implanted pure iron was lower than 2%. However, zinc ions might induce more adhered and activated platelets on the surface of pure iron. Overall, zinc ion implantation can be a feasible way to accelerate the degradation rate of pure iron for biodegradable applications. PMID:27482462

  5. Shallow nitrogen ion implantation: Evolution of chemical state and defect structure in titanium

    NASA Astrophysics Data System (ADS)

    Manojkumar, P. A.; Chirayath, V. A.; Balamurugan, A. K.; Krishna, Nanda Gopala; Ilango, S.; Kamruddin, M.; Amarendra, G.; Tyagi, A. K.; Raj, Baldev

    2016-09-01

    Evolution of chemical states and defect structure in titanium during low energy nitrogen ion implantation by Plasma Immersion Ion Implantation (PIII) process is studied. The underlying process of chemical state evolution is investigated using secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The implantation induced defect structure evolution as a function of dose is elucidated using variable energy positron annihilation Doppler broadening spectroscopy (PAS) and the results were corroborated with chemical state. Formation of 3 layers of defect state was modeled to fit PAS results.

  6. Doping of ion implanted polyethylene with metallocarborane

    NASA Astrophysics Data System (ADS)

    Hnatowicz, V.; Vacík, J.; Červená, J.; Švorčík, V.; Rybka, V.; Popok, V.; Fink, D.; Klett, R.

    1995-11-01

    Polyethylene samples implanted with 150 keV F + ions to the doses from 5 × 10 13-1 × 10 15cm -2 were exposed to 0.05 M water solution of metallocarborane [(C 2B 9H 11) 2Co]Cs at temperatures of 24, 50 and 85°C, and the diffusion and incorporation of elements in the sample surface layer were studied using Rutherford back-scattering and neutron depth profiling techniques. The amount of incorporated B and Cs atoms was found to be an increasing function of the temperature for all implanted doses. The indiffusion and incorporation of the [(C 2B 9H 11) 2Co] - anion and the Cs + cation proceed separately and the final {B}/{Cs} ratio is well below metallocarborane stoichiometry in most cases. The total amount of incorporated Cs and B atoms and their depth profiles depend on the implanted dose in very complicated manner. For lower implanted doses anomalous depth profiles of B and Cs, roughly following calculated profiles of electronic energy loss of F + ions are observed.

  7. Laser annealing of ion implanted silicon

    SciTech Connect

    White, C.W.; Appleton, B.R.; Wilson, S.R.

    1980-01-01

    Pulsed laser annealing of ion implanted silicon leads to the formation of supersaturated alloys by nonequilibrium crystal growth processes at the interface occurring during liquid phase epitaxial regrowth. The interfacial distribution coefficients from the melt (k') and the maximum substitutional solubilities (C/sub s//sup max/) are far greater than equilibrium values. Both K' and C/sub s//sup max/ are functions of growth velocity. Mechanisms limiting substitutional solubilities are discussed. 5 figures, 2 tables.

  8. Damage accumulation in ceramics during ion implantation

    SciTech Connect

    McHargue, C.J.; Farlow, G.C.; Begun, G.M.; Williams, J.M.; White, C.W.; Appleton, B.R.; Sklad, P.S.; Angelini, P.

    1985-01-01

    The damage structures of ..cap alpha..-Al/sub 2/O/sub 3/ and ..cap alpha..-SiC were examined as functions of ion implantation parameters using Rutherford backscattering-channeling, analytical electron microscopy, and Raman spectroscopy. Low temperatures or high fluences of cations favor formation of the amorphous state. At 300/sup 0/K, mass of the bombarding species has only a small effect on residual damage, but certain ion species appear to stabilize the damage microstructure and increase the rate of approach to the amorphous state. The type of chemical bonding present in the host lattice is an important factor in determining the residual damage state.

  9. Integral stress in ion-implanted silicon

    NASA Astrophysics Data System (ADS)

    Tamulevicius, S.; Pozela, I.; Jankauskas, J.

    1998-11-01

    A theoretical model of production and relaxation of stress in ion-implanted silicon is proposed. It is based on the assumptions that the point defects are the source of mechanical stress and that the relaxation of stress is due to the viscous flow of ion-irradiated silicon. The integrated stress acting in a damaged layer has been studied as a function of the 0022-3727/31/21/002/img1-ion current density j = 0.01-0022-3727/31/21/002/img2, ion energy 0022-3727/31/21/002/img3-160 keV, substrate temperature T = 78-500 K and dose in the range up to 0022-3727/31/21/002/img4. It was shown that the maximum integral stress values induced in silicon are of the order of 100 N 0022-3727/31/21/002/img5. The maximum is reached at a dose of about 0022-3727/31/21/002/img6 that corresponds to the silicon-amorphization dose. Stress due to implanted ions is essential for the high-dose region 0022-3727/31/21/002/img7 and it dominates at high temperatures of the substrate.

  10. Plasma polymerization for cell adhesive/anti-adhesive implant coating

    NASA Astrophysics Data System (ADS)

    Meichsner, Juergen; Testrich, Holger; Rebl, Henrike; Nebe, Barbara

    2015-09-01

    Plasma polymerization of ethylenediamine (C2H8N2, EDA) and perfluoropropane (C3F8, PFP) with admixture of argon and hydrogen, respectively, was studied using an asymmetric 13.56 MHz CCP. The analysis of the plasma chemical gas phase processes for stable molecules revealed consecutive reactions: C2H8N2 consumption, intermediate product NH3, and main final product HCN. In C3F8- H2 plasma the precursor molecule C3F8 and molecular hydrogen are consumed and HF as well as CF4 and C2F6 are found as main gaseous reaction products. The deposited plasma polymer films on the powered electrode are strongly cross-linked due to ion bombardment. The stable plasma polymerized films from EDA are characterized by high content of nitrogen with N/C ratio of about 0.35. The plasma polymerized fluorocarbon film exhibit a reduced F/C ratio of about 1.2. Adhesion tests with human osteoblast cell line MG-63 on coated Ti6Al4V samples (polished) compared with uncoated reference sample yielded both, the enhanced cell adhesion for plasma polymerized EDA and significantly reduced cell adhesion for fluorocarbon coating, respectively. Aging of the plasma polymerized EDA film, in particular due to the reactions with oxygen from air, showed no significant change in the cell adhesion. The fluorocarbon coating with low cell adhesion is of interest for temporary implants. Funded by the Campus PlasmaMed.

  11. Effect of fluoride-ion implantation on the biocompatibility of titanium for dental applications

    NASA Astrophysics Data System (ADS)

    Liu, H. Y.; Wang, X. J.; Wang, L. P.; Lei, F. Y.; Wang, X. F.; Ai, H. J.

    2008-08-01

    This study stressed on the effect of fluoride-ion implantation upon the biocompatibility of titanium. By using plasma immersion ion implantation technique, fluoride ions were implanted into the smooth surface of pure titanium. The chemical composition and physical structure of the modified surface layers were characterized by X-ray photoelectron spectroscopy (XPS) as well as scanning electron microscope (SEM). At the same time, in vitro co-culture assays were performed to evaluate the biocompatibility of MG-63 cells to the modified titanium. It was confirmed by SEM observations that cell growth on the fluoride-ion-implanted titanium acquired better morphological characters. In addition, the cells on the fluoride-ion-implanted titanium showed the more increasingly and rapidly substrates-attaching capabilities than those on the non-implanted titanium via aridine orange stain assay. Fluoride-ion-implanted titanium could increase the percentages of cells in S phase but without affecting the ratios of cells in G 0/G 1 and G 2/M phases was confirmed by flow cytometry assay. The current results indicated that fluoride-ion implantation could improve the biocompatibility of titanium.

  12. Influence of ion source configuration and its operation parameters on the target sputtering and implantation process.

    PubMed

    Shalnov, K V; Kukhta, V R; Uemura, K; Ito, Y

    2012-06-01

    In the work, investigation of the features and operation regimes of sputter enhanced ion-plasma source are presented. The source is based on the target sputtering with the dense plasma formed in the crossed electric and magnetic fields. It allows operation with noble or reactive gases at low pressure discharge regimes, and, the resulting ion beam is the mixture of ions from the working gas and sputtering target. Any conductive material, such as metals, alloys, or compounds, can be used as the sputtering target. Effectiveness of target sputtering process with the plasma was investigated dependently on the gun geometry, plasma parameters, and the target bias voltage. With the applied accelerating voltage from 0 to 20 kV, the source can be operated in regimes of thin film deposition, ion-beam mixing, and ion implantation. Multi-component ion beam implantation was applied to α-Fe, which leads to the surface hardness increasing from 2 GPa in the initial condition up to 3.5 GPa in case of combined N(2)-C implantation. Projected range of the implanted elements is up to 20 nm with the implantation energy 20 keV that was obtained with XPS depth profiling.

  13. In vivo stimulation of bone formation by aluminum and oxygen plasma surface-modified magnesium implants.

    PubMed

    Wong, Hoi Man; Zhao, Ying; Tam, Vivian; Wu, Shuilin; Chu, Paul K; Zheng, Yufeng; To, Michael Kai Tsun; Leung, Frankie K L; Luk, Keith D K; Cheung, Kenneth M C; Yeung, Kelvin W K

    2013-12-01

    A newly developed magnesium implant is used to stimulate bone formation in vivo. The magnesium implant after undergoing dual aluminum and oxygen plasma implantation is able to suppress rapid corrosion, leaching of magnesium ions, as well as hydrogen gas release from the biodegradable alloy in simulated body fluid (SBF). No released aluminum is detected from the SBF extract and enhanced corrosion resistance properties are confirmed by electrochemical tests. In vitro studies reveal enhanced growth of GFP mouse osteoblasts on the aluminum oxide coated sample, but not on the untreated sample. In addition to that a small amount (50 ppm) of magnesium ions can enhance osteogenic differentiation as reported previously, our present data show a low concentration of hydrogen can give rise to the same effect. To compare the bone volume change between the plasma-treated magnesium implant and untreated control, micro-computed tomography is performed and the plasma-treated implant is found to induce significant new bone formation adjacent to the implant from day 1 until the end of the animal study. On the contrary, bone loss is observed during the first week post-operation from the untreated magnesium sample. Owing to the protection offered by the Al2O3 layer, the plasma-treated implant degrades more slowly and the small amount of released magnesium ions stimulate new bone formation locally as revealed by histological analyses. Scanning electron microscopy discloses that the Al2O3 layer at the bone-implant interface is still present two months after implantation. In addition, no inflammation or tissue necrosis is observed from both treated and untreated implants. These promising results suggest that the plasma-treated magnesium implant can stimulate bone formation in vivo in a minimal invasive way and without causing post-operative complications.

  14. Computer automation of high current ion implanters

    NASA Astrophysics Data System (ADS)

    Woodard, Ollie; Lindsey, Paul; Cecil, Joseph; Pipe, Robert

    1985-01-01

    Complete computer automation of a high current ion implanter has been achieved. Special design considerations were necessary for automation including the development of a simplified ion source, a simplified beam transport control function, and a computer aided real-time feedback dosimetry control system. A special, versatile software architecture was also necessary to allow protected operation by unskilled operators, as well as diagnostic and maintenance modes accessible only to qualified personnel. Integral mounting of the DEC LSI-11 computer in the implanter frame provided additional challenges regarding EMI control and the electrical isolation required. The end result is a system in which all pertinent functions of the implanter are computer monitored and controlled continuously, allowing for automatic set-up, operation, on-line fault detection and diagnostics, with recovery software to correct many transient problems as they occur. This paper will discuss both general and specific solutions to the design problems encountered, and will review the system performance from a user point of view.

  15. Nitrogen depth profiles in plasma implanted stainless steel

    NASA Astrophysics Data System (ADS)

    Tian, Xiubo; Kwok, Dixon T. K.; Chu, Paul K.; Chan, Chung

    2002-07-01

    Nitrogen plasma immersion ion implantation (PIII) is a useful technique to enhance the surface properties of stainless steels and the in-depth distribution of the implanted nitrogen is a crucial parameter. A comparison of the nitrogen depth profiles in AISI 304 stainless steel reported in the literature and observed in our laboratory with the one simulated using a plasma sheath model and TRIM shows a discrepancy. The simulated profile is non-Gaussian and shallower due to the non-perfect high voltage pulses whereas the experimental profile is a better fit to a Gaussian distribution. Since most PIII equipment is not designed for ultra-high vacuum (UHV) operation and the plasma is highly reactive in this environment, the surface of the implanted samples is easily contaminated by a large amount of atmospheric species such as oxygen and carbon from the residual vacuum in the processing chamber, thereby converting the materials surface into an oxidized and carburized form. The change in the matrix composition in the near surface skews and translates the nitrogen depth profile obtained by Auger electron spectroscopy. By normalizing the nitrogen signal point-by-point with the combined (Fe+Cr+Ni) signal, a more accurate depth profile can be obtained. This type of normalization, albeit common in secondary ion mass spectrometry (SIMS) data quantification, is seldom implemented in the plasma community when dealing with nitrogen depth profiles acquired by Auger electron spectroscopy. Our results indicate that the excessively high surface contamination renders the raw nitrogen depth profile inaccurate and a proper normalization measure must be adopted.

  16. Ion-Implanted Diamond Films and Their Tribological Properties

    NASA Technical Reports Server (NTRS)

    Wu, Richard L. C.; Miyoshi, Kazuhisa; Korenyi-Both, Andras L.; Garscadden, Alan; Barnes, Paul N.

    1993-01-01

    This paper reports the physical characterization and tribological evaluation of ion-implanted diamond films. Diamond films were produced by microwave plasma, chemical vapor deposition technique. Diamond films with various grain sizes (0.3 and 3 microns) and roughness (9.1 and 92.1 nm r.m.s. respectively) were implanted with C(+) (m/e = 12) at an ion energy of 160 eV and a fluence of 6.72 x 10(exp 17) ions/sq cm. Unidirectional sliding friction experiments were conducted in ultrahigh vacuum (6.6 x 10(exp -7)Pa), dry nitrogen and humid air (40% RH) environments. The effects of C(+) ion bombardment on fine and coarse-grained diamond films are as follows: the surface morphology of the diamond films did not change; the surface roughness increased (16.3 and 135.3 nm r.m.s.); the diamond structures were damaged and formed a thin layer of amorphous non-diamond carbon; the friction coefficients dramatically decreased in the ultrahigh vacuum (0.1 and 0.4); the friction coefficients decreased slightly in the dry nitrogen and humid air environments.

  17. Computational stochastic model of ions implantation

    SciTech Connect

    Zmievskaya, Galina I. Bondareva, Anna L.; Levchenko, Tatiana V.; Maino, Giuseppe

    2015-03-10

    Implantation flux ions into crystal leads to phase transition /PT/ 1-st kind. Damaging lattice is associated with processes clustering vacancies and gaseous bubbles as well their brownian motion. System of stochastic differential equations /SDEs/ Ito for evolution stochastic dynamical variables corresponds to the superposition Wiener processes. The kinetic equations in partial derivatives /KE/, Kolmogorov-Feller and Einstein-Smolukhovskii, were formulated for nucleation into lattice of weakly soluble gases. According theory, coefficients of stochastic and kinetic equations uniquely related. Radiation stimulated phase transition are characterized by kinetic distribution functions /DFs/ of implanted clusters versus their sizes and depth of gas penetration into lattice. Macroscopic parameters of kinetics such as the porosity and stress calculated in thin layers metal/dielectric due to Xe{sup ++} irradiation are attracted as example. Predictions of porosity, important for validation accumulation stresses in surfaces, can be applied at restoring of objects the cultural heritage.

  18. Production technology for high efficiency ion implanted solar cells

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. R.; Minnucci, J. A.; Greenwald, A. C.; Josephs, R. H.

    1978-01-01

    Ion implantation is being developed for high volume automated production of silicon solar cells. An implanter designed for solar cell processing and able to properly implant up to 300 4-inch wafers per hour is now operational. A machine to implant 180 sq m/hr of solar cell material has been designed. Implanted silicon solar cells with efficiencies exceeding 16% AM1 are now being produced and higher efficiencies are expected. Ion implantation and transient processing by pulsed electron beams are being integrated with electrostatic bonding to accomplish a simple method for large scale, low cost production of high efficiency solar cell arrays.

  19. Ion radiation albedo effect: influence of surface roughness on ion implantation and sputtering of materials

    NASA Astrophysics Data System (ADS)

    Li, Yonggang; Yang, Yang; Short, Michael P.; Ding, Zejun; Zeng, Zhi; Li, Ju

    2017-01-01

    In fusion devices, ion retention and sputtering of materials are major concerns in the selection of compatible plasma-facing materials (PFMs), especially in the context of their microstructural conditions and surface morphologies. We demonstrate how surface roughness changes ion implantation and sputtering of materials under energetic ion irradiation. Using a new, sophisticated 3D Monte Carlo (MC) code, IM3D, and a random rough surface model, ion implantation and the sputtering yields of tungsten (W) with a surface roughness varying between 0-2 µm have been studied for irradiation by 0.1-1 keV D+, He+ and Ar+ ions. It is found that both ion backscattering and sputtering yields decrease with increasing roughness; this is hereafter called the ion radiation albedo effect. This effect is mainly dominated by the direct, line-of-sight deposition of a fraction of emitted atoms onto neighboring asperities. Backscattering and sputtering increase with more oblique irradiation angles. We propose a simple analytical formula to relate rough-surface and smooth-surface results.

  20. Biodegradable radioactive implants for glaucoma filtering surgery produced by ion implantation

    NASA Astrophysics Data System (ADS)

    Assmann, W.; Schubert, M.; Held, A.; Pichler, A.; Chill, A.; Kiermaier, S.; Schlösser, K.; Busch, H.; Schenk, K.; Streufert, D.; Lanzl, I.

    2007-04-01

    A biodegradable, β-emitting implant has been developed and successfully tested which prevents fresh intraocular pressure increase after glaucoma filtering surgery. Ion implantation has been used to load the polymeric implants with the β-emitter 32P. The influence of ion implantation and gamma sterilisation on degradation and 32P-fixation behavior has been studied by ion beam and chemical analysis. Irradiation effects due to the applied ion fluence (1015 ions/cm2) and gamma dose (25 kGy) are found to be tolerable.

  1. Radiation hardened PMOS process with ion implanted threshold adjust

    NASA Technical Reports Server (NTRS)

    Jhabvala, M.

    1979-01-01

    By including specific process modifications the effect of ion implantation on radiation hardness can be minimized and radiation hard ion implanted MOS circuits can be fabricated. The experimental procedure followed was to examine key processing steps (with respect to radiation hardness) on ion-implanted individual PMOS transistors. The individual transistors were evaluated by continuously monitoring the threshold voltage as the transistors were being irradiated. By comparing runs it was possible to deduce what is considered a radiation hard ion implanted process. Tests with a complex LSI PMOS IC processor chip containing over 2000 transistors and resistors were also conducted

  2. Ion implantation effects in 'cosmic' dust grains

    NASA Technical Reports Server (NTRS)

    Bibring, J. P.; Langevin, Y.; Maurette, M.; Meunier, R.; Jouffrey, B.; Jouret, C.

    1974-01-01

    Cosmic dust grains, whatever their origin may be, have probably suffered a complex sequence of events including exposure to high doses of low-energy nuclear particles and cycles of turbulent motions. High-voltage electron microscope observations of micron-sized grains either naturally exposed to space environmental parameters on the lunar surface or artificially subjected to space simulated conditions strongly suggest that such events could drastically modify the mineralogical composition of the grains and considerably ease their aggregation during collisions at low speeds. Furthermore, combined mass spectrometer and ionic analyzer studies show that small carbon compounds can be both synthesized during the implantation of a mixture of low-energy D, C, N ions in various solids and released in space by ion sputtering.

  3. Ion Kinetics in Silane Plasmas

    DTIC Science & Technology

    1988-02-01

    reaction are determined not only by the chemical reactivity but by the electrical properties of the plasma. Current continuity, impedence match- ing...conventional kinetic theory. Since the chemical and physical properties of the noble-gases vary monotonically down the periods of Mendeleev’s table, one...formation. Most literature with the phrase ion chemistry in its title is concerned only with the properties and reactions of positively charged species

  4. Some plasma aspects and plasma diagnostics of ion sources.

    PubMed

    Wiesemann, Klaus

    2008-02-01

    We consider plasma properties in the most advanced type of plasma ion sources, electron cyclotron resonance ion sources for highly charged ions. Depending on the operation conditions the plasma in these sources may be highly ionized, which completely changes its transport properties. The most striking difference to weakly ionized plasma is that diffusion will become intrinsically ambipolar. We further discuss means of plasma diagnostics. As noninvasive diagnostic methods we will discuss analysis of the ion beam, optical spectroscopy, and measurement of the x-ray bremsstrahlung continuum. From beam analysis and optical spectroscopy one may deduce ion densities, and electron densities and distribution functions as a mean over the line of sight along the axis (optical spectroscopy) or at the plasma edge (ion beam). From x-ray spectra one obtains information about the population of highly energetic electrons and the energy transfer from the driving electromagnetic waves to the plasma -- basic data for plasma modeling.

  5. Plasma ion sources and ion beam technology inmicrofabrications

    SciTech Connect

    Ji, Lili

    2007-01-01

    For over decades, focused ion beam (FIB) has been playing a very important role in microscale technology and research, among which, semiconductor microfabrication is one of its biggest application area. As the dimensions of IC devices are scaled down, it has shown the need for new ion beam tools and new approaches to the fabrication of small-scale devices. In the meanwhile, nanotechnology has also deeply involved in material science research and bioresearch in recent years. The conventional FIB systems which utilize liquid gallium ion sources to achieve nanometer scale resolution can no longer meet the various requirements raised from such a wide application area such as low contamination, high throughput and so on. The drive towards controlling materials properties at nanometer length scales relies on the availability of efficient tools. In this thesis, three novel ion beam tools have been developed and investigated as the alternatives for the conventional FIB systems in some particular applications. An integrated focused ion beam (FIB) and scanning electron microscope (SEM) system has been developed for direct doping or surface modification. This new instrument employs a mini-RF driven plasma source to generate focused ion beam with various ion species, a FEI two-lens electron (2LE) column for SEM imaging, and a five-axis manipulator system for sample positioning. An all-electrostatic two-lens column has been designed to focus the ion beam extracted from the source. Based on the Munro ion optics simulation, beam spot sizes as small as 100 nm can be achieved at beam energies between 5 to 35 keV if a 5 μm-diameter extraction aperture is used. Smaller beam spot sizes can be obtained with smaller apertures at sacrifice of some beam current. The FEI 2LE column, which utilizes Schottky emission, electrostatic focusing optics, and stacked-disk column construction, can provide high-resolution (as small as 20 nm) imaging capability, with fairly long working distance (25

  6. Properties of ion implanted Ti-6Al-4V processed using beamline and PSII techniques

    SciTech Connect

    Walter, K.C.; Woodring, J.S.; Nastasi, M.; Munson, C.M.; Williams, J.M.; Poker, D.B.

    1996-12-31

    The surface of Ti-6Al-4V (Ti64) alloy has been modified using beamline implantation of boron. In separate experiments, Ti64 has been implanted with nitrogen using a plasma source ion implantation (PSII) technique utilizing either ammonia (NH{sub 3}), nitrogen (N{sub 2}), or their combinations as the source of nitrogen ions. Beamline experiments have shown the hardness of the N-implanted surface saturates at a dose level of {approximately} 4 {times} 10{sup 17} at/cm{sup 2} at {approximately} 10 GPa. The present work makes comparisons of hardness and tribological tests of (1) B implantation using beamline techniques, and (2) N implanted samples using ammonia and/or nitrogen gas in a PSII process. The results show that PSII using N{sub 2} or NH{sub 3} gives similar hardness as N implantation using a beamline process. The presence of H in the Ti alloy surface does not affect the hardness of the implanted surface. Boron implantation increased the surface hardness by as much as 2.5x at the highest dose level. Wear testing by a pin-on-disk method indicated that nitrogen implantation reduced the wear rate by as much as 120x, and boron implantation reduced the wear rate by 6.5x. Increased wear resistance was accompanied by a decreased coefficient of friction.

  7. Mg ion implantation on SLA-treated titanium surface and its effects on the behavior of mesenchymal stem cell.

    PubMed

    Kim, Beom-Su; Kim, Jin Seong; Park, Young Min; Choi, Bo-Young; Lee, Jun

    2013-04-01

    Magnesium (Mg) is one of the most important ions associated with bone osseointegration. The aim of this study was to evaluate the cellular effects of Mg implantation in titanium (Ti) surfaces treated with sand blast using large grit and acid etching (SLA). Mg ions were implanted into the surface via vacuum arc source ion implantation. The surface morphology, chemical properties, and the amount of Mg ion release were evaluated by scanning electron microscopy (SEM), Auger electron spectroscopy (AES), Rutherford backscattering spectroscopy (RBS), and inductively coupled plasma-optical emission spectrometer (ICP-OES). Human mesenchymal stem cells (hMSCs) were used to evaluate cellular parameters such as proliferation, cytotoxicity, and adhesion morphology by MTS assay, live/dead assay, and SEM. Furthermore, osteoblast differentiation was determined on the basis of alkaline phosphatase (ALP) activity and the degree of calcium accumulation. In the Mg ion-implanted disk, 2.3×10(16) ions/cm(2) was retained. However, after Mg ion implantation, the surface morphology did not change. Implanted Mg ions were rapidly released during the first 7 days in vitro. The MTS assay, live/dead assay, and SEM demonstrated increased cell attachment and growth on the Mg ion-implanted surface. In particular, Mg ion implantation increased the initial cell adhesion, and in an osteoblast differentiation assay, ALP activity and calcium accumulation. These findings suggest that Mg ion implantation using the plasma source ion implantation (PSII) technique may be useful for SLA-treated Ti dental implants to improve their osseointegration capacity.

  8. PLEPS study of ions implanted RAFM steels

    NASA Astrophysics Data System (ADS)

    Sojak, S.; Slugeň, V.; Egger, W.; Ravelli, L.; Petriska, M.; Veterníková, J.; Stacho, M.; Sabelová, V.

    2014-04-01

    Current nuclear power plants (NPP) require radiation, heat and mechanical resistance of their structural materials with the ability to stay operational during NPP planned lifetime. Radiation damage much higher, than in the current NPP, is expected in new generations of nuclear power plants, such as Generation IV and fusion reactors. Investigation of perspective structural materials for new generations of nuclear power plants is among others focused on study of reduced activation ferritic/martensitic (RAFM) steels. These steels have good characteristics as reduced activation, good resistance to volume swelling, good radiation, and heat resistance. Our experiments were focused on the study of microstructural changes of binary Fe-Cr alloys with different chromium content after irradiation, experimentally simulated by ion implantations. Fe-Cr alloys were examined, by Pulsed Low Energy Positron System (PLEPS) at FRM II reactor in Garching (Munich), after helium ion implantations at the dose of 0.1 C/cm2. The investigation was focused on the chromium effect and the radiation defects resistivity. In particular, the vacancy type defects (monovacancies, vacancy clusters) have been studied. Based on our previous results achieved by conventional lifetime technique, the decrease of the defects size with increasing content of chromium is expected also for PLEPS measurements.

  9. All-ion-implantation process for integrated circuits

    NASA Technical Reports Server (NTRS)

    Woo, D. S.

    1979-01-01

    Simpler than diffusion fabrication, ion bombardment produces complementary-metal-oxide-semiconductor / silicon-on-sapphire (CMOS/SOS) circuits that are one-third faster. Ion implantation simplifies the integrated circuit fabrication procedure and produces circuits with uniform characteristics.

  10. MEVVA ion-implantation of high Tc superconductors

    NASA Astrophysics Data System (ADS)

    Martin, J. W.; Cohen, D. D.; Russell, G. J.; Dytlewski, N.; Evans, P. J.

    1995-12-01

    Metallised vapour vacuum arc (MEVVA) ion-implantation has been used to implant transition metal ions into high quality superconductor materials. Analysis of the samples was by the relatively new technique of heavy ion elastic recoil time-of-flight spectroscopy (ERTOFS), employing a 77 MeV 127I 10+ beam. The HIERTOFS technique is ideally suited to samples of this nature, providing individual depth profiles for each element within the matrix. The results were found to be implant-ion species dependent, with ions such as Ni and Co having differing effects to that of Fe. This paper will report on the use of ERTOFS as a method to obtain individual implant and substrate profiles from the ion-beam modified materials.

  11. Applications of ion implantation for high efficiency silicon solar cells

    NASA Technical Reports Server (NTRS)

    Minnucci, J. A.; Kirkpatrick, A. R.

    1977-01-01

    Ion implantation is utilized for the dopant introduction processes necessary to fabricate a silicon solar cell. Implantation provides a versatile powerful tool for development of high efficiency cells. Advantages and problems of implantation and the present status of developmental use of the technique for solar cells are discussed.

  12. Modeling of nanocluster formation by ion beam implantation

    SciTech Connect

    Li, Kun-Dar

    2011-08-15

    A theoretical model was developed to investigate the mechanism of the formation of nanoclusters via ion beam implantation. The evolution of nanoclusters, including the nucleation and growth process known as Ostwald ripening, was rebuilt using numerical simulations. The effects of implantation parameters such as the ion energy, ion fluence, and temperature on the morphology of implanted microstructures were also studied through integration with the Monte Carlo Transport of Ions in Matter code calculation for the distribution profiles of implanted ions. With an appropriate ion fluence, a labyrinth-like nanostructure with broad size distributions of nanoclusters formed along the ion implantation range. In a latter stage, a buried layer of implanted impurity developed. With decreasing ion energy, the model predicted the formation of precipitates on the surface. These simulation results were fully consistent with many experimental observations. With increased temperature, the characteristic length and size of nanostructures would increase due to the high mobility. This theoretical model provides an efficient numerical approach for fully understanding the mechanism of the formation of nanoclusters, allowing for the design of ion beam experiments to form specific nanostructures through ion-implantation technology.

  13. Mechanical stresses and amorphization of ion-implanted diamond

    NASA Astrophysics Data System (ADS)

    Khmelnitsky, R. A.; Dravin, V. A.; Tal, A. A.; Latushko, M. I.; Khomich, A. A.; Khomich, A. V.; Trushin, A. S.; Alekseev, A. A.; Terentiev, S. A.

    2013-06-01

    Scanning white light interferometry and Raman spectroscopy were used to investigate the mechanical stresses and structural changes in ion-implanted natural diamonds with different impurity content. The uniform distribution of radiation defects in implanted area was obtained by the regime of multiple-energy implantation of keV He+ ions. A modification of Bosia's et al. (Nucl. Instrum. Meth. B 268 (2010) 2991) method for determining the internal stresses and the density variation in an ion-implanted diamond layer was proposed that suggests measuring, in addition to the surface swelling of a diamond plate, the radius of curvature of the plate. It is shown that, under multiple-energy implantation of He+, mechanical stresses in the implanted layer may be as high as 12 GPa. It is shown that radiation damage reaches saturation for the implantation fluence characteristic of amorphization of diamond but is appreciably lower than the graphitization threshold.

  14. Ion dynamics in the plasma mantle

    NASA Astrophysics Data System (ADS)

    Akinrimisi, J.; Orsini, S.; Candidi, M.; Balsiger, H.

    1990-11-01

    A comprehensive statistical analysis has been performed on plasma mantle data from the positive ion experiment (EGD) on ISEE-2 and the Ion Composition Experiment (ICE) on ISEE-1; the data were collected during the first six months of 1978 and 1979 in the earth's magnetotail. Particular emphasis has been placed on plasma mantle-plasma sheet crossings so as to elucidate the role of mantle plasma in the refilling of the plasma sheet. It is shown that mantle plasma contiguous to the plasma sheet is convected primarily away from the magnetopause toward the center of the tail equatorial region. Evidence is found in the data that, when the mantle plasma reaches a region close to the plasma sheet, it undergoes processes of energization and thermalization. The mantle plasma characteristics gradually change to those of the plasma sheet as observed immediately after, suggesting that the same plasma has changed properties in such a way as to become plasma sheet plasma.

  15. High Density Ion Implanted Contiguous Disk Bubble Technology

    DTIC Science & Technology

    1989-03-31

    regions. The flux from this stripe domain will intercept the magnetodiodes as shown in figure 1-12, and the Lorentz force (F = qv x B) will act on the...Following the propagation implant, the photoresist implant mask is removed with an air plasma in a barrel etcher. A 0.15,rm plasma SiO 2 layer is then

  16. Ion Beam Analysis applied to laser-generated plasmas

    NASA Astrophysics Data System (ADS)

    Cutroneo, M.; Macková, A.; Havranek, V.; Malinsky, P.; Torrisi, L.; Kormunda, M.; Barchuk, M.; Ullschmied, J.; Dudzak, R.

    2016-04-01

    This paper presents the research activity on Ion Beam Analysis methods performed at Tandetron Laboratory (LT) of the Institute of Nuclear Physics AS CR, Rez, Czech Republic. Recently, many groups are paying attention to implantation by laser generated plasma. This process allows to insert a controllable amount of energetic ions into the surface layers of different materials modifying the physical and chemical properties of the surface material. Different substrates are implanted by accelerated ions from plasma through terawatt iodine laser, at nominal intensity of 1015 W/cm2, at the PALS Research Infrastructure AS CR, in the Czech Republic. This regime of the laser matter interaction generates, multi-MeV proton beams, and multi-charged ions that are tightly confined in time (hundreds ps) and space (source radius of a few microns). These ion beams have a much lower transverse temperature, a much shorter duration and a much higher current than those obtainable from conventional accelerators. The implementation of protons and ions acceleration driven by ultra-short high intensity lasers is exhibited by adopting suitable irradiation conditions as well as tailored targets. An overview of implanted targets and their morphological and structural characterizations is presented and discussed.

  17. Ion-implanted extrinsic Ge photodetectors with extended cutoff wavelength

    NASA Technical Reports Server (NTRS)

    Wu, I. C.; Beeman, J. W.; Luke, P. N.; Hansen, W. L.; Haller, E. E.

    1991-01-01

    Far-IR Ge detectors fabricated using boron ion implantation are shown to exhibit operating characteristics compatible with requirements for low background applications. Device parameters such as low dark currents, reasonably good sensitivity, and extended wavelength threshold demonstrate that ion-implanted Ge far-IR detectors offer promise for use in astrophysics instrumentation.

  18. Formation of hexagonal 9R silicon polytype by ion implantation

    NASA Astrophysics Data System (ADS)

    Korolev, D. S.; Nikolskaya, A. A.; Krivulin, N. O.; Belov, A. I.; Mikhaylov, A. N.; Pavlov, D. A.; Tetelbaum, D. I.; Sobolev, N. A.; Kumar, M.

    2017-08-01

    Transmission electron-microscopy examination revealed the appearance of a hexagonal silicon (9R polytype) inclusions in the subsrface silicon layer upon ion implantation and subsequent heat treatment of the SiO2/Si structure. The formation of this hexagonal phase is stimulated by mechanical stresses arising in the heterophase system in the course of ion implantation.

  19. Ion implantation of highly corrosive electrolyte battery components

    DOEpatents

    Muller, R.H.; Zhang, S.

    1997-01-14

    A method of producing corrosion resistant electrodes and other surfaces in corrosive batteries using ion implantation is described. Solid electrically conductive material is used as the ion implantation source. Battery electrode grids, especially anode grids, can be produced with greatly increased corrosion resistance for use in lead acid, molten salt, and sodium sulfur. 6 figs.

  20. Ion implantation of highly corrosive electrolyte battery components

    DOEpatents

    Muller, Rolf H.; Zhang, Shengtao

    1997-01-01

    A method of producing corrosion resistant electrodes and other surfaces in corrosive batteries using ion implantation is described. Solid electrically conductive material is used as the ion implantation source. Battery electrode grids, especially anode grids, can be produced with greatly increased corrosion resistance for use in lead acid, molten salt, end sodium sulfur.

  1. Surface and corrosion characteristics of carbon plasma implanted and deposited nickel-titanium alloy

    SciTech Connect

    Poon, R.W.Y.; Liu, X.Y.; Chung, C.Y.; Chu, P.K.; Yeung, K.W.K.; Lu, W.W.; Cheung, K.M.C.

    2005-05-01

    Nickel-titanium shape memory alloys (NiTi) are potentially useful in orthopedic implants on account of their super-elastic and shape memory properties. However, the materials are prone to surface corrosion and the most common problem is out-diffusion of harmful Ni ions from the substrate into body tissues and fluids. In order to improve the corrosion resistance and related surface properties, we used the technique of plasma immersion ion implantation and deposition to deposit an amorphous hydrogenated carbon coating onto NiTi and implant carbon into NiTi. Both the deposited amorphous carbon film and carbon plasma implanted samples exhibit much improved corrosion resistances and surface mechanical properties and possible mechanisms are suggested.

  2. Streaming instability in negative ion plasma

    NASA Astrophysics Data System (ADS)

    Kumar, Ajith; Mathew, Vincent

    2017-09-01

    The streaming instability in an unmagnetized negative ion plasma has been studied by computational and theoretical methods. A one dimensional electrostatic Particle In Cell Simulation and fluid dynamical description of negative ion plasma showed that, if the positive ions are having a relative streaming velocity, four different wave modes corresponding to Langmuir wave, fast and slow ion waves and ion acoustic waves are produced. Below a critical wave number, instead of two distinct fast and slow ion waves, we observed a coupled wave mode. The value of the critical wave number is strongly determined by the ion streaming velocity. The thermal velocities of electrons and ions influence the growth rate of instability.

  3. Self-organized surface ripple pattern formation by ion implantation

    NASA Astrophysics Data System (ADS)

    Hofsäss, Hans; Zhang, Kun; Bobes, Omar

    2016-10-01

    Ion induced ripple pattern formation on solid surfaces has been extensively studied in the past and the theories describing curvature dependent ion erosion as well as redistribution of recoil atoms have been very successful in explaining many features of the pattern formation. Since most experimental studies use noble gas ion irradiation, the incorporation of the ions into the films is usually neglected. In this work we show that the incorporation or implantation of non-volatile ions also leads to a curvature dependent term in the equation of motion of a surface height profile. The implantation of ions can be interpreted as a negative sputter yield; and therefore, the effect of ion implantation is opposite to the one of ion erosion. For angles up to about 50°, implantation of ions stabilizes the surface, whereas above 50°, ion implantation contributes to the destabilization of the surface. We present simulations of the curvature coefficients using the crater function formalism and we compare the simulation results to the experimental data on the ion induced pattern formation using non-volatile ions. We present several model cases, where the incorporation of ions is a crucial requirement for the pattern formation.

  4. Ion-beam Plasma Neutralization Interaction Images

    SciTech Connect

    Igor D. Kaganovich; Edward Startsev; S. Klasky; Ronald C. Davidson

    2002-04-09

    Neutralization of the ion beam charge and current is an important scientific issue for many practical applications. The process of ion beam charge and current neutralization is complex because the excitation of nonlinear plasma waves may occur. Computer simulation images of plasma neutralization of the ion beam pulse are presented.

  5. Nitrogen ion implantation into various materials using 28 GHz electron cyclotron resonance ion source

    SciTech Connect

    Shin, Chang Seouk; Lee, Byoung-Seob; Choi, Seyong; Yoon, Jang-Hee; Kim, Hyun Gyu; Ok, Jung-Woo; Park, Jin Yong; Kim, Seong Jun; Bahng, Jungbae; Hong, Jonggi; Won, Mi-Sook; Lee, Seung Wook

    2016-02-15

    The installation of the 28 GHz electron cyclotron resonance ion source (ECRIS) ion implantation beamline was recently completed at the Korea Basic Science Institute. The apparatus contains a beam monitoring system and a sample holder for the ion implantation process. The new implantation system can function as a multipurpose tool since it can implant a variety of ions, ranging hydrogen to uranium, into different materials with precise control and with implantation areas as large as 1–10 mm{sup 2}. The implantation chamber was designed to measure the beam properties with a diagnostic system as well as to perform ion implantation with an in situ system including a mass spectrometer. This advanced implantation system can be employed in novel applications, including the production of a variety of new materials such as metals, polymers, and ceramics and the irradiation testing and fabrication of structural and functional materials to be used in future nuclear fusion reactors. In this investigation, the first nitrogen ion implantation experiments were conducted using the new system. The 28 GHz ECRIS implanted low-energy, multi-charged nitrogen ions into copper, zinc, and cobalt substrates, and the ion implantation depth profiles were obtained. SRIM 2013 code was used to calculate the profiles under identical conditions, and the experimental and simulation results are presented and compared in this report. The depths and ranges of the ion distributions in the experimental and simulation results agree closely and demonstrate that the new system will enable the treatment of various substrates for advanced materials research.

  6. Nitrogen ion implantation into various materials using 28 GHz electron cyclotron resonance ion source.

    PubMed

    Shin, Chang Seouk; Lee, Byoung-Seob; Choi, Seyong; Yoon, Jang-Hee; Kim, Hyun Gyu; Ok, Jung-Woo; Park, Jin Yong; Kim, Seong Jun; Bahng, Jungbae; Hong, Jonggi; Lee, Seung Wook; Won, Mi-Sook

    2016-02-01

    The installation of the 28 GHz electron cyclotron resonance ion source (ECRIS) ion implantation beamline was recently completed at the Korea Basic Science Institute. The apparatus contains a beam monitoring system and a sample holder for the ion implantation process. The new implantation system can function as a multipurpose tool since it can implant a variety of ions, ranging hydrogen to uranium, into different materials with precise control and with implantation areas as large as 1-10 mm(2). The implantation chamber was designed to measure the beam properties with a diagnostic system as well as to perform ion implantation with an in situ system including a mass spectrometer. This advanced implantation system can be employed in novel applications, including the production of a variety of new materials such as metals, polymers, and ceramics and the irradiation testing and fabrication of structural and functional materials to be used in future nuclear fusion reactors. In this investigation, the first nitrogen ion implantation experiments were conducted using the new system. The 28 GHz ECRIS implanted low-energy, multi-charged nitrogen ions into copper, zinc, and cobalt substrates, and the ion implantation depth profiles were obtained. SRIM 2013 code was used to calculate the profiles under identical conditions, and the experimental and simulation results are presented and compared in this report. The depths and ranges of the ion distributions in the experimental and simulation results agree closely and demonstrate that the new system will enable the treatment of various substrates for advanced materials research.

  7. Nitrogen ion implantation into various materials using 28 GHz electron cyclotron resonance ion source

    NASA Astrophysics Data System (ADS)

    Shin, Chang Seouk; Lee, Byoung-Seob; Choi, Seyong; Yoon, Jang-Hee; Kim, Hyun Gyu; Ok, Jung-Woo; Park, Jin Yong; Kim, Seong Jun; Bahng, Jungbae; Hong, Jonggi; Lee, Seung Wook; Won, Mi-Sook

    2016-02-01

    The installation of the 28 GHz electron cyclotron resonance ion source (ECRIS) ion implantation beamline was recently completed at the Korea Basic Science Institute. The apparatus contains a beam monitoring system and a sample holder for the ion implantation process. The new implantation system can function as a multipurpose tool since it can implant a variety of ions, ranging hydrogen to uranium, into different materials with precise control and with implantation areas as large as 1-10 mm2. The implantation chamber was designed to measure the beam properties with a diagnostic system as well as to perform ion implantation with an in situ system including a mass spectrometer. This advanced implantation system can be employed in novel applications, including the production of a variety of new materials such as metals, polymers, and ceramics and the irradiation testing and fabrication of structural and functional materials to be used in future nuclear fusion reactors. In this investigation, the first nitrogen ion implantation experiments were conducted using the new system. The 28 GHz ECRIS implanted low-energy, multi-charged nitrogen ions into copper, zinc, and cobalt substrates, and the ion implantation depth profiles were obtained. SRIM 2013 code was used to calculate the profiles under identical conditions, and the experimental and simulation results are presented and compared in this report. The depths and ranges of the ion distributions in the experimental and simulation results agree closely and demonstrate that the new system will enable the treatment of various substrates for advanced materials research.

  8. Sources and transport systems for low energy extreme of ion implantation

    SciTech Connect

    Hershcovitch, A.; Batalin, V.A.; Bugaev, A.S.; Gushenets, V.I.; Alexeyenko, O.; Gurkova, E.; Johnson, B.M.; Kolomiets, A.A.; Kropachev, G.N.; Kuibeda, R.P.; Kulevoy, T.V.; Masunov, E.S.; Oks, E.M.; Pershin, V.I.; Polozov, S.M.; Poole, H.J.; Seleznev, D.N.; Storozhenko, P.A.; Vizir, A.; Svarovski, A.Ya.; Yakushin, P.; Yushkov, G.Yu.

    2010-06-06

    For the past seven years a joint research and development effort focusing on the design of steady state, intense ion sources has been in progress with the ultimate goal being to meet the two, energy extreme range needs of mega-electron-volt and 100's of electron-volt ion implanters. However, since the last Fortier is low energy ion implantation, focus of the endeavor has shifted to low energy ion implantation. For boron cluster source development, we started with molecular ions of decaborane (B{sub 10}H{sub 14}), octadecaborane (B{sub 18}H{sub 22}), and presently our focus is on carborane (C{sub 2}B{sub 10}H{sub 12}) ions developing methods for mitigating graphite deposition. Simultaneously, we are developing a pure boron ion source (without a working gas) that can form the basis for a novel, more efficient, plasma immersion source. Our Calutron-Berna ion source was converted into a universal source capable of switching between generating molecular phosphorous P{sub 4}{sup +}, high charge state ions, as well as other types of ions. Additionally, we have developed transport systems capable of transporting a very large variety of ion species, and simulations of a novel gasless/plasmaless ion beam deceleration method were also performed.

  9. Dynamic MC simulation of low-energy ion implantation

    NASA Astrophysics Data System (ADS)

    Yamamura, Y.

    1999-06-01

    In order to investigate the ion fluence effect in the depth profiles of the dynamic Monte Carlo code, ACAT-DIFFUSE, is applied to the calculation of depth profiles due to low-energy B ion implantation, where 1 and 5 keV B ions are implanted into an amorphized silicon target. As the ion fluence increases, the dopant B atoms are accumulated in solids and the target must be considered as a two-component material composed of the original target atoms and trapped implanted ions. This results in the radiation-induced-diffusion and the self-sputtering of trapped implanted ions. It is found that the peak locations of the dopant B depth profiles at 1 keV B ion bombardment shifted to the surface due to radiation-induced diffusion as ion increased and we observe the near-the-surface enhancement in the dopant B depth profiles due to 5 keV B ion bombardment. The self-sputtering also becomes important with increasing ion fluence. The retention ratios of the implanted B atoms are about 0.89 and 0.94 for 1 and 5 keV B ions, respectively, at 3.0 × 10 13 B ions/cm 2.

  10. Implantation of nitrogen, carbon, and phosphorus ions into metals

    SciTech Connect

    Guseva, M.I.; Gordeeva, G.V.

    1987-01-01

    The application of ion implantation for alloying offers a unique opportunity to modify the chemical composition, phase constitution, and microstructure of the surface layers of metals. The authors studied ion implantation of nitrogen and carbon into the surface layers of metallic targets. The phase composition of the implanted layers obtained on the Kh18N10T stainless steel, the refractory molybdenum alloy TsM-6, niobium, and nickel was determined according to the conventional method of recording the x-ray diffraction pattern of the specimens using monochromatic FeK/sub alpha/-radiation on a DRON-2,0 diffractometer. The targets were bombarded at room temperature in an ILU-3 ion accelerator. The implantation of metalloid ions was also conducted with the targets being bombarded with 100-keV phosphorus ions and 40-keV carbon ions.

  11. Ultrahigh-current-density metal-ion implantation and diamondlike-hydrocarbon films for tribological applications

    NASA Astrophysics Data System (ADS)

    Wilbur, P. J.

    1993-09-01

    The metal-ion-implantation system used to implant metals into substrates are described. The metal vapor required for operation is supplied by drawing sufficient electron current from the plasma discharge to an anode-potential crucible so a solid, pure metal placed in the crucible will be heated to the point of vaporization. The ion-producing, plasma discharge is initiated within a graphite-ion-source body, which operates at high temperature, by using an argon flow that is turned off once the metal vapor is present. Extraction of ion beams several cm in diameter at current densities ranging to several hundred micro-A/sq cm on a target 50 cm downstream of the ion source were demonstrated using Mg, Ag, Cr, Cu, Si, Ti, V, B, and Zr. These metals were implanted into over 100 substrates (discs, pins, flats, wires). A model describing thermal stresses induced in materials (e.g. ceramic plates) during high-current-density implantation is presented. Tribological and microstructural characteristics of iron and 304-stainless-steel samples implanted with Ti or B are examined. Diamondlike-hydrocarbon coatings were applied to steel surfaces and found to exhibit good tribological performance.

  12. The effect of plasma surface treatment on the bioactivity of titanium implant materials (in vitro).

    PubMed

    Abdelrahim, Ramy A; Badr, Nadia A; Baroudi, Kusai

    2016-01-01

    The surface of an implantable biomaterial plays a very important role in determining the biocompatibility, osteoinduction, and osteointegration of implants because it is in intimate contact with the host bone and soft tissues. This study was aimed to assess the effect of plasma surface treatment on the bioactivity of titanium alloy (Ti-6Al-4V). Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (with five samples in each group). Five samples were kept untreated and served as control (group A). Another five plasma samples were sprayed for nitrogen ion implantation on their surfaces (group B) and the last five samples were pre-etched with acid before plasma treatment (group C). All the investigated samples were immersed for 7 days in Hank's balanced salt solution (HBSS) which was used as a simulating body fluid (SBF) at pH 7.4 and 37°C. HBSS was renewed every 3 days. The different surfaces were characterized by X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXA), and Fourier Transformation Infrared Spectroscopy (FTIR). Nitriding of Ti-alloy samples via plasma nitrogen ion implantation increased the bioactivity of titanium. Moreover, the surface topography affected the chemical structure of the formed apatite. Increasing the surface roughness enhanced the bioactivity of the implant material. Nitridation can be exploited as an effective way to promote the formation of bone-like material on the implant surface.

  13. Arsenic ion implant energy effects on CMOS gate oxide hardness.

    SciTech Connect

    Dondero, Richard; Headley, Thomas Jeffrey; Young, Ralph Watson; Draper, Bruce Leroy; Shaneyfelt, Marty Ray

    2005-07-01

    Under conditions that were predicted as 'safe' by well-established TCAD packages, radiation hardness can still be significantly degraded by a few lucky arsenic ions reaching the gate oxide during self-aligned CMOS source/drain ion implantation. The most likely explanation is that both oxide traps and interface traps are created when ions penetrate and damage the gate oxide after channeling or traveling along polysilicon grain boundaries during the implantation process.

  14. Human study of ion implantation as a surface treatment for dental implants.

    PubMed

    De Maeztu, M A; Braceras, I; Álava, J I; Recio, C; Piñera, M; Gay-Escoda, C

    2013-07-01

    This clinical study evaluated a new surface treatment of ion implantation with CO ions which has previously been subjected to extensive study in animal models. The aim of this work was to assess its effect in humans. Experimental mini-implants were used; half of their longitudinal surface was machined and the other half was treated with CO ion implantation. The study was conducted in healthy volunteer patients who required prosthetic treatment with dental implants, and in accordance with the corresponding ethics committees. Coinciding with the insertion of commercial implants for oral restoration, one or two mini-implants were placed in the upper maxillary tuberosity or in the retromolar trigone of the mandible. The mini-implants were removed with a trephine jointly with a small volume of surrounding bone after a 3-month period. Two evaluation methods were used and both showed a greater degree of bone integration in the mini-implant section that underwent CO ion implantation treatment in comparison with the non-treated surface: 62.9% vs. 57.9%, and 54.8% vs. 46.2%. In addition, no adverse reactions were observed in the surface treatment with CO ion implantation. These results confirm the positive benefits in humans, based on the findings obtained from previous animal experiments.

  15. Study of ion-irradiated tungsten in deuterium plasma

    NASA Astrophysics Data System (ADS)

    Khripunov, B. I.; Gureev, V. M.; Koidan, V. S.; Kornienko, S. N.; Latushkin, S. T.; Petrov, V. B.; Ryazanov, A. I.; Semenov, E. V.; Stolyarova, V. G.; Danelyan, L. S.; Kulikauskas, V. S.; Zatekin, V. V.; Unezhev, V. N.

    2013-07-01

    Experimental study aimed at investigation of neutron induced damage influence on fusion reactor plasma facing materials is reported. Displacement damage was produced in tungsten by high-energy helium and carbon ions at 3-10 MeV. The reached level of displacement damage ranged from several dpa to 600 dpa. The properties of the irradiated tungsten were studied in steady-state deuterium plasma on the LENTA linear divertor simulator. Plasma exposures were made at 250 eV of ion energy to fluence 1021-1022 ion/сm2. Erosion dynamics of the damaged layer and deuterium retention were observed. Surface microstructure modifications and important damage of the 5 μm layer shown. Deuterium retention in helium-damaged tungsten (ERD) showed its complex behavior (increase or decrease) depending on implanted helium quantity and the structure of the surface layer.

  16. Evaluation of titanium plasma-sprayed and plasma-sprayed hydroxyapatite implants in vivo.

    PubMed

    Ong, Joo L; Carnes, David L; Bessho, Kazuhisa

    2004-08-01

    In this study, bone interfacial strength and bone contact length at the plasma-sprayed hydroxyapatite (HA) and titanium plasma-sprayed (TPS) implants were evaluated in vivo. Non-coated titanium (Ti) implants were used as controls. Cylindrical coated or non-coated implants (4.0mm diameter by 8mm long) were implanted in the dogs' mandibles. Loading of the implants was performed at 12 weeks after implantation. At 12 weeks after implantation (prior to loading) and 1 year after loading, implants were evaluated for interfacial bone-implant strength and bone-implant contact length. No significant differences in interfacial bone-implant strength for all groups at 12 weeks after implantation and after 1 year loading in normal bone were found. However, bone contact length for HA implants was significantly higher than the TPS and Ti implants for both periods tested (12 weeks after implantation and 1 year after loading). It was concluded that TPS implants exhibited similar pull-out strength compared to the HA implants. In addition, the lower bone contact length on the TPS surface compared to HA surfaces did not affect the interfacial bone-implant strength for both implants.

  17. Characteristics of radial ion-plasma accelerators

    NASA Astrophysics Data System (ADS)

    Bondarenko, S. M.; Korolev, C. V.; Movsesyants, Yu B.; Tyuryukanov, P. M.

    2017-07-01

    The characteristics of two-stage ion-plasma accelerators are presented. These accelerators are based on a discharge in a transverse highly-inhomogeneous magnetic field and can form radially converging and divergent flows. It is shown that for a radially convergent flow the width of the ion acceleration zone is limited by the condition of a transition through the ion sound point in the vicinity of the plasma ion emitting boundary.

  18. The use of ion implantation for materials processing

    NASA Astrophysics Data System (ADS)

    Smidt, F. A.

    1986-03-01

    This report is the sixth in a series of Progress Reports on work conducted at the Naval Research Laboratory (NRL) to investigate the use of ion implantation for materials processing. The objective of the program is to develop the capabilities of ion implantation and ion beam activated deposition for new and improved surface treatment techniques of interest to Navy and DOD applications. Attainment of this objective requires both fundamental research to provide an understanding of the physical and metallurgical changes taking place in the implanted region of a material and applications oriented research to demonstrate the benefits of ion implantation. The purpose of this report is to make available from one source the results of all studies at NRL related to the use of ion implantation for materials processing so as to provide a more comprehensive picture of the scope and interrelationship of the research and to expedite technology transfer to the civilian industrial sector. The report consists of four sections describing the research and a cummulative bibliography of published papers and reports. This report describes the important factors in ion implantation science and technology and reports progress in the use of ion implantation to modify friction, wear, fatigue, corrosion, optical and magnetic properties of materials.

  19. The Effect of Carbon Dioxide and Nitrogen ion implantation of AISI 52100 Steel

    NASA Astrophysics Data System (ADS)

    Sari, Amir H.; Ghoranneviss, M.; Mardanian, M.; Hantehzadeh, M. R.; Hora, H.

    2003-06-01

    Ion implantation has been used to modify the mechanical properties of a wide range of metals and alloys using plasma techniques for ion sources and plasma surface treatment [1]. In this study AISI 52100 steel disks, containing 1.5 wt% Cr as the major alloying element, were implanted with nitrogen and carbon dioxide ions at the energy of 90 KeV, with dose in the range 1 × 1018 to 1 × 1019 N2+ ions cm-2, and 3 × 1018 to 1 × 1019 for co2+ ions cm-2. Ion beam current densities and sample temperature, during implantation were 3-6 μA/cm2 and 170°C, respectively. Experiments show, hardness of sample, increases 30-49% using N2+ ions, and 5-17% using co2+ ions. In order to explain the results, formation of beta-CrN and carbide pahses have been carried out using X-ray diffraction technique.

  20. Photosensitivity enhancement of PLZT ceramics by positive ion implantation

    DOEpatents

    Peercy, P.S.; Land, C.E.

    1980-06-13

    The photosensitivity of lead lanthanum zirconate titanate (PLZT) ceramic material used in high resolution, high contrast, and non-volatile photoferroelectric image storage and display devices is enhanced significantly by positive ion implantation of the PLZT near its surface. Ions that are implanted include H/sup +/, He/sup +/, Ar/sup +/, and a preferred co-implant of Ar/sup +/ and Ne/sup +/. The positive ion implantation advantageously serves to shift the band gap energy threshold of the PLZT material from near-uv light to visible blue light. As a result, photosensitivity enhancement is such that the positive ion implanted PLZT plate is sensitive even to sunlight and conventional room lighting, such as fluorescent and incandescent light sources. The method disclosed includes exposing the PLZT plate to these positive ions of sufficient density and with sufficient energy to provide an image. The PLZT material may have a lanthanum content ranging from 5 to 10%; a lead zirconate content ranging from 62 to 70 mole %; and a lead titanate content ranging from 38 to 30%. The region of ion implantation is in a range from 0.1 to 2 microns below the surface of the PLZT plate. Density of ions is in the range from 1 x 10/sup 12/ to 1 x 10/sup 17/ ions/cm/sup 2/ and having an energy in the range from 100 to 500 keV.

  1. Ion implantation in silicon to facilitate testing of photonic circuits

    NASA Astrophysics Data System (ADS)

    Reed, Graham T.; Milosevic, Milan M.; Chen, Xia; Cao, Wei; Littlejohns, Callum G.; Wang, Hong; Khokhar, Ali Z.; Thomson, David J.

    2017-02-01

    In recent years, we have presented results on the development of erasable gratings in silicon to facilitate wafer scale testing of photonics circuits via ion implantation of germanium. Similar technology can be employed to develop a range of optical devices that are reported in this paper. Ion implantation into silicon causes radiation damage resulting in a refractive index increase, and can therefore form the basis of multiple optical devices. We demonstrate the principle of a series of devices for wafers scale testing and have also implemented the ion implantation based refractive index change in integrated photonics devices for device trimming.

  2. Ion-implanted planar-buried-heterostructure diode laser

    DOEpatents

    Brennan, Thomas M.; Hammons, Burrell E.; Myers, David R.; Vawter, Gregory A.

    1991-01-01

    A Planar-Buried-Heterostructure, Graded-Index, Separate-Confinement-Heterostructure semiconductor diode laser 10 includes a single quantum well or multi-quantum well active stripe 12 disposed between a p-type compositionally graded Group III-V cladding layer 14 and an n-type compositionally graded Group III-V cladding layer 16. The laser 10 includes an ion implanted n-type region 28 within the p-type cladding layer 14 and further includes an ion implanted p-type region 26 within the n-type cladding layer 16. The ion implanted regions are disposed for defining a lateral extent of the active stripe.

  3. Software for goniometer control in the Triple Ion Implantation Facility

    SciTech Connect

    Allen, W.R.

    1994-02-01

    A computer program is described tat controls the goniometer employed in the ion scattering chamber of the Triple Ion Implantation Facility (TIF) in the Metals and Ceramics Division at Oak Ridge National Laboratory. Details of goniometer operation and its incorporation into the ion scattering setup specific to the TIF are also discussed.

  4. Ion implantation induced nanotopography on titanium and bone cell adhesion

    NASA Astrophysics Data System (ADS)

    Braceras, Iñigo; Vera, Carolina; Ayerdi-Izquierdo, Ana; Muñoz, Roberto; Lorenzo, Jaione; Alvarez, Noelia; de Maeztu, Miguel Ángel

    2014-08-01

    Permanent endo-osseous implants require a fast, reliable and consistent osseointegration, i.e. intimate bonding between bone and implant, so biomechanical loads can be safely transferred. Among the parameters that affect this process, it is widely admitted that implant surface topography, surface energy and composition play an important role. Most surface treatments to improve osseointegration focus on micro-scale features, as few can effectively control the effects of the treatment at nanoscale. On the other hand, ion implantation allows controlling such nanofeatures. This study has investigated the nanotopography of titanium, as induced by different ion implantation surface treatments, its similarity with human bone tissue structure and its effect on human bone cell adhesion, as a first step in the process of osseointegration. The effect of ion implantation treatment parameters such as energy (40-80 keV), fluence (1-2 e17 ion/cm2) and ion species (Kr, Ar, Ne and Xe) on the nanotopography of medical grade titanium has been measured and assessed by AFM and contact angle. Then, in vitro tests have been performed to assess the effect of these nanotopographies on osteoblast adhesion. The results have shown that the nanostructure of bone and the studied ion implanted surfaces, without surface chemistry modification, are in the same range and that such modifications, in certain conditions, do have a statistically significant effect on bone tissue forming cell adhesion.

  5. Modification of polyvinyl alcohol surface properties by ion implantation

    NASA Astrophysics Data System (ADS)

    Pukhova, I. V.; Kurzina, I. A.; Savkin, K. P.; Laput, O. A.; Oks, E. M.

    2017-05-01

    We describe our investigations of the surface physicochemical properties of polyvinyl alcohol modified by silver, argon and carbon ion implantation to doses of 1 × 1014, 1 × 1015 and 1 × 1016 ion/cm2 and energies of 20 keV (for C and Ar) and 40 keV (for Ag). Infrared spectroscopy (IRS) indicates that destructive processes accompanied by chemical bond (sbnd Cdbnd O) generation are induced by implantation, and X-ray photoelectron spectroscopy (XPS) analysis indicates that the implanted silver is in a metallic Ag3d state without stable chemical bond formation with polymer chains. Ion implantation is found to affect the surface energy: the polar component increases while the dispersion part decreases with increasing implantation dose. Surface roughness is greater after ion implantation and the hydrophobicity increases with increasing dose, for all ion species. We find that ion implantation of Ag, Ar and C leads to a reduction in the polymer microhardness by a factor of five, while the surface electrical resistivity declines modestly.

  6. Development of vertical compact ion implanter for gemstones applications

    NASA Astrophysics Data System (ADS)

    Intarasiri, S.; Wijaikhum, A.; Bootkul, D.; Suwannakachorn, D.; Tippawan, U.; Yu, L. D.; Singkarat, S.

    2014-08-01

    Ion implantation technique was applied as an effective non-toxic treatment of the local Thai natural corundum including sapphires and rubies for the enhancement of essential qualities of the gemstones. Energetic oxygen and nitrogen ions in keV range of various fluences were implanted into the precious stones. It has been thoroughly proved that ion implantation can definitely modify the gems to desirable colors together with changing their color distribution, transparency and luster properties. These modifications lead to the improvement in quality of the natural corundum and thus its market value. Possible mechanisms of these modifications have been proposed. The main causes could be the changes in oxidation states of impurities of transition metals, induction of charge transfer from one metal cation to another and the production of color centers. For these purposes, an ion implanter of the kind that is traditionally used in semiconductor wafer fabrication had already been successfully applied for the ion beam bombardment of natural corundum. However, it is not practical for implanting the irregular shape and size of gem samples, and too costly to be economically accepted by the gem and jewelry industry. Accordingly, a specialized ion implanter has been requested by the gem traders. We have succeeded in developing a prototype high-current vertical compact ion implanter only 1.36 m long, from ion source to irradiation chamber, for these purposes. It has been proved to be very effective for corundum, for example, color improvement of blue sapphire, induction of violet sapphire from low value pink sapphire, and amelioration of lead-glass-filled rubies. Details of the implanter and recent implantation results are presented.

  7. Method of fabricating optical waveguides by ion implantation doping

    DOEpatents

    Appleton, Bill R.; Ashley, Paul R.; Buchal, Christopher J.

    1989-01-01

    A method for fabricating high-quality optical waveguides in optical quality oxide crystals by ion implantation doping and controlled epitaxial recrystallization is provided. Masked LiNbO.sub.3 crystals are implanted with high concentrations of Ti dopant at ion energies of about 350 keV while maintaining the crystal near liquid nitrogen temperature. Ion implantation doping produces an amorphous, Ti-rich nonequilibrium phase in the implanted region. Subsequent thermal annealing in a water-saturated oxygen atmosphere at up to 1000.degree. C. produces solid-phase epitaxial regrowth onto the crystalline substrate. A high-quality single crystalline layer results which incorporates the Ti into the crystal structure at much higher concentrations than is possible by standard diffusion techniques, and this implanted region has excellent optical waveguides properties.

  8. Method of fabricating optical waveguides by ion implantation doping

    DOEpatents

    Appleton, B.R.; Ashley, P.R.; Buchal, C.J.

    1987-03-24

    A method for fabricating high-quality optical waveguides in optical quality oxide crystals by ion implantation doping and controlled epitaxial recrystallization is provided. Masked LiNbO/sub 3/ crystals are implanted with high concentrations of Ti dopant at ion energies of about 360 keV while maintaining the crystal near liquid nitrogen temperature. Ion implantation doping produces an amorphous, Ti-rich nonequilibrium phase in the implanted region. Subsequent thermal annealing in a water-saturated oxygen atmosphere at up to 1000/degree/C produces solid-phase epitaxial regrowth onto the crystalline substrate. A high-quality crystalline layer results which incorporates the Ti into the crystal structure at much higher concentrations than is possible by standard diffusion techniques, and this implanted region has excellent optical waveguiding properties.

  9. Development of vacuum arc ion sources for heavy ion accelerator injectors and ion implantation technology (invited)

    NASA Astrophysics Data System (ADS)

    Oks, Efim M.

    1998-02-01

    The status of experimental research and ongoing development and upgrade of MEVVA-type ion sources over the last two years since the previous ICIS-95 is reviewed. There are two main application fields for this ion source: heavy ion accelerators and material surface implantation technology. For particle accelerator ion injection to accelerators it is important to enhance the fractions of multiply charged ions in the ion beam as well as controlling the charge state distribution, and to improve of beam current stability (i.e., to minimize the beam noise) and pulse-to-pulse reproducibility. For ion implantation application we need to increase both the implantation dose rate and the source lifetime (between required maintenance downtime) as well as making this kind of source more reliable and of yet low cost. Most of experimental results reported on here have been obtained in a collaborative program between research groups LBNL (Berkeley, USA), GSI (Darmstadt, Germany), HCEI (Tomsk, Russia), and other important contributions have been made by the groups at (BNU, Beijing, China), EDU (Izmir, Turkey), and elsewhere.

  10. Improving Sustainability of Ion Implant Modules

    NASA Astrophysics Data System (ADS)

    Mayer, Jim

    2011-01-01

    Semiconductor fabs have long been pressured to manage capital costs, reduce energy consumption and increasingly improve efforts to recycle and recover resources. Ion implant tools have been high-profile offenders on all three fronts. They draw such large volumes of air for heat dissipation and risk reduction that historically, they are the largest consumer of cleanroom air of any process tool—and develop energy usage and resource profiles to match. This paper presents a documented approach to reduce their energy consumption and dramatically downsize on-site facilities support for cleanroom air manufacture and abatement. The combination produces significant capital expenditure savings. The case entails applying SAGS Type 1 (sub-atmospheric gas systems) toxic gas packaging to enable engineering adaptations that deliver the energy savings and cost benefits without any reduction in environmental health and safety. The paper also summarizes benefits as they relate to reducing a fabs carbon emission footprint (and longer range advantages relative to potential cap and trade programs) with existing technology.

  11. Industrial applications of ion implantation into metal surfaces

    SciTech Connect

    Williams, J.M.

    1987-07-01

    The modern materials processing technique, ion implantation, has intriguing and attractive features that stimulate the imaginations of scientists and technologists. Success of the technique for introducing dopants into semiconductors has resulted in a stable and growing infrastructure of capital equipment and skills for use of the technique in the economy. Attention has turned to possible use of ion implantation for modification of nearly all surface related properties of materials - optical, chemical and corrosive, tribological, and several others. This presentation provides an introduction to fundamental aspects of equipment, technique, and materials science of ion implantation. Practical and economic factors pertaining to the technology are discussed. Applications and potential applications are surveyed. There are already available a number of ion-implanted products, including ball-and-roller bearings and races, punches-and-dies, injection screws for plastics molding, etc., of potential interest to the machine tool industry.

  12. Plasma formed ion beam projection lithography system

    DOEpatents

    Leung, Ka-Ngo; Lee, Yung-Hee Yvette; Ngo, Vinh; Zahir, Nastaran

    2002-01-01

    A plasma-formed ion-beam projection lithography (IPL) system eliminates the acceleration stage between the ion source and stencil mask of a conventional IPL system. Instead a much thicker mask is used as a beam forming or extraction electrode, positioned next to the plasma in the ion source. Thus the entire beam forming electrode or mask is illuminated uniformly with the source plasma. The extracted beam passes through an acceleration and reduction stage onto the resist coated wafer. Low energy ions, about 30 eV, pass through the mask, minimizing heating, scattering, and sputtering.

  13. Characterization of Ion Implanted and Laser Processed Wear Surfaces.

    DTIC Science & Technology

    1986-04-22

    Cavitation erosion tests were performed on nonimplanted and ion implanted samples of a Co’based hardface alloy (Stoody 3). Erosion of the test samples was...implanted samples of a Co-based hardface alloy (Stoody 3). Erosion of the test samples was found to initiate by debonding at the carbide-matrix interfaces

  14. Studies on Amorphizing Silicon Using Silicon Ion Implantation.

    DTIC Science & Technology

    1985-04-01

    130-200 keV ions with doses of 5 x 1014 to 2 x 1015 2 15 2ions/cm and for 0.5 micron films, 260-300 keV ions at 1-2 x 10 ions/cm . Svensson et al...Vol. 42, pp. 707-709, 1983. 17. B. Svensson , J. Linnros & G. Holmen, "Ion Beam Induced Annealing of Radiation Damage in Silicon on Sapphire," Nucl...Mayer, Lennart Eriksson & John A. Davies, Ion Implantation in Semiconductors, Academic Press, NY, 1970. 21. L. T. Chadderton & F. H. Eisen, editors. Ion

  15. Enhancement of Ag nanoparticles concentration by prior ion implantation

    NASA Astrophysics Data System (ADS)

    Mu, Xiaoyu; Wang, Jun; Liu, Changlong

    2017-09-01

    Thermally grown SiO2 layer on Si substrates were singly or sequentially implanted with Zn or Cu and Ag ions at the same fluence of 2 × 1016/cm2. The profiles of implanted species, structure, and spatial distribution of the formed nanoparticles (NPs) have been characterized by the cross-sectional transmission electron microscope (XTEM) and Rutherford backscattering spectrometry (RBS). It is found that pre-implantation of Zn or Cu ions could suppress the self sputtering of Ag atoms during post Ag ion implantation, which gives rise to fabrication of Ag NPs with a high density. Moreover, it has also been demonstrated that the suppressing effect strongly depends on the applied energy and mobility of pre-implanted ions. The possible mechanism for the enhanced Ag NPs concentration has been discussed in combination with SRIM simulations. Both vacancy-like defects acting as the increased nucleation sites for Ag NPs and a high diffusivity of prior implanted ions in SiO2 play key roles in enhancing the deposition of Ag implants.

  16. Shallow junction formation by polyatomic cluster ion implantation

    SciTech Connect

    Takeuchi, Daisuke; Shimada, Norihiro; Matsuo, Jiro; Yamada, Isao

    1996-12-31

    Recent integrated circuits require shallow junctions which are less than 0.1 {mu}m depth. This creates a strong demand for low energy ion beam techniques. Equivalent low-energy and high-current ion beams can be realized quite easily with clusters, because the kinetic energy of the cluster is shared between the constituent atoms. Additionally, cluster-ion beams avoid damage due to excessive charge. We have used polyatomic clusters, decaborane (B{sub 10}H{sub 14}), as a kind of B cluster, in order to form a very shallow p{sup +} junction. A B SIMS profile of B{sub 10}H{sub 14} implanted into Si (100) at 20keV was quite similar to that of B implanted at 2keV. These SIMS measurements revealed that the cluster ion beam can realize equivalent low-energy implantation quite easily. The implantation efficiency achieved was about 90%. The damage induced by B{sub 10}H{sub 14} implantation was completely removed by a 600{degrees}C furnace anneal for 30 min, and implanted B atoms were electrically activated. After rapid thermal annealing (RTA) at 900{degrees}C of a sample prepared with a close of 5{times}10{sup 13} ion/cm{sup 2}, the sheet resistance decreased to about 600W/sq. and the activation efficiency was about 50%. These results show that a polyatomic cluster ion beam is useful for shallow junction formation.

  17. Ion loss in weakly collisional three ion species plasmas

    NASA Astrophysics Data System (ADS)

    Hershkowitz, Noah; Yip, Chi-Shung; Severn, Greg

    2016-10-01

    Ion velocity distribution functions (ivdfs) at sheath-presheath boundaries are studied with laser-induced fluorescence in weakly collisional Xe-Kr-Ar and Xe-Ar-Ne plasmas using tunable diode lasers for Ar + and Xe + ions. The argon and xenon ivdfs are measured at the sheath-presheath boundary near a negatively biased boundary plate. The plasma potential profiles are measured by an emissive probe throughout the sheath and presheath. Relative ion concentrations resulting from the neutral gas mixtures are calculated using G-H. Kim's loss-production balance method. Ne + and Kr + ions are added to plasmas with approximately equal amounts of Ar + and Xr + ions, where Ar + and Xe + ions are previously observed to reach the sheath edge at nearly the system sound speed. In two ion species plasmas, instability enhanced collisional friction was demonstrated to dictate the escape velocities of the ions. When three ion species are present, it is demonstrated that as the concentration of the third ion species increases, Xe + and Ar + ion velocities at the sheath edge deviates from the common sound speed and approach their individual Bohm velocities. These observations are consistent with the predictions of the instability enhanced collisional friction theory This work was supported by NSF under Grant No. 1464741 and U.S. DOE under Grant No. DE-SC00114226.

  18. Inductively generated streaming plasma ion source

    DOEpatents

    Glidden, Steven C.; Sanders, Howard D.; Greenly, John B.

    2006-07-25

    A novel pulsed, neutralized ion beam source is provided. The source uses pulsed inductive breakdown of neutral gas, and magnetic acceleration and control of the resulting plasma, to form a beam. The beam supplies ions for applications requiring excellent control of ion species, low remittance, high current density, and spatial uniformity.

  19. A Nanoscale-Localized Ion Damage Josephson Junction Using Focused Ion Beam and Ion Implanter.

    PubMed

    Wu, C H; Ku, W S; Jhan, F J; Chen, J H; Jeng, J T

    2015-05-01

    High-T(c) Josephson junctions were fabricated by nanolithography using focused ion beam (FIB) milling and ion implantation. The junctions were formed in a YBa2Cu3O7-x, thin film in regions defined using a gold-film mask with 50-nm-wide (top) slits, engraved by FIB. The focused ion beam system parameters for dwell time and passes were set to remove gold up to a precise depth. 150 keV oxygen ions were implanted at a nominal dose of up to 5 x 10(13) ions/cm2 into YBa2Cu3O7-x microbridges through the nanoscale slits. The current-voltage curves of the ion implantation junctions exhibit resistive-shunted-junction-like behavior at 77 K. The junction had an approximately linear temperature dependence of critical current. Shapiro steps were observed under microwave irradiation. A 50-nm-wide slit and 0-20-nm-thick buffer layers were chosen in order to make Josephson junctions due to the V-shape of the FIB-milled trench.

  20. Bone tissue response to plasma-nitrided titanium implant surfaces

    PubMed Central

    FERRAZ, Emanuela Prado; SVERZUT, Alexander Tadeu; FREITAS, Gileade Pereira; SÁ, Juliana Carvalho; ALVES, Clodomiro; BELOTI, Marcio Mateus; ROSA, Adalberto Luiz

    2015-01-01

    A current goal of dental implant research is the development of titanium (Ti) surfaces to improve osseointegration. Plasma nitriding treatments generate surfaces that favor osteoblast differentiation, a key event to the process of osteogenesis. Based on this, it is possible to hypothesize that plasma-nitrided Ti implants may positively impact osseointegration. Objective The aim of this study was to evaluate the in vivo bone response to Ti surfaces modified by plasma-nitriding treatments. Material and Methods Surface treatments consisted of 20% N2 and 80% H2, 450°C and 1.5 mbar during 1 h for planar and 3 h for hollow cathode. Untreated surface was used as control. Ten implants of each surface were placed into rabbit tibiae and 6 weeks post-implantation they were harvested for histological and histomorphometric analyses. Results Bone formation was observed in contact with all implants without statistically significant differences among the evaluated surfaces in terms of bone-to-implant contact, bone area between threads, and bone area within the mirror area. Conclusion Our results indicate that plasma nitriding treatments generate Ti implants that induce similar bone response to the untreated ones. Thus, as these treatments improve the physico-chemical properties of Ti without affecting its biocompatibility, they could be combined with modifications that favor bone formation in order to develop new implant surfaces. PMID:25760262

  1. Bone tissue response to plasma-nitrided titanium implant surfaces.

    PubMed

    Ferraz, Emanuela Prado; Sverzut, Alexander Tadeu; Freitas, Gileade Pereira; Sá, Juliana Carvalho; Alves, Clodomiro; Beloti, Marcio Mateus; Rosa, Adalberto Luiz

    2015-01-01

    A current goal of dental implant research is the development of titanium (Ti) surfaces to improve osseointegration. Plasma nitriding treatments generate surfaces that favor osteoblast differentiation, a key event to the process of osteogenesis. Based on this, it is possible to hypothesize that plasma-nitrided Ti implants may positively impact osseointegration. Objective The aim of this study was to evaluate the in vivo bone response to Ti surfaces modified by plasma-nitriding treatments. Material and Methods Surface treatments consisted of 20% N2 and 80% H2, 450°C and 1.5 mbar during 1 h for planar and 3 h for hollow cathode. Untreated surface was used as control. Ten implants of each surface were placed into rabbit tibiae and 6 weeks post-implantation they were harvested for histological and histomorphometric analyses. Results Bone formation was observed in contact with all implants without statistically significant differences among the evaluated surfaces in terms of bone-to-implant contact, bone area between threads, and bone area within the mirror area. Conclusion Our results indicate that plasma nitriding treatments generate Ti implants that induce similar bone response to the untreated ones. Thus, as these treatments improve the physico-chemical properties of Ti without affecting its biocompatibility, they could be combined with modifications that favor bone formation in order to develop new implant surfaces.

  2. Hydrogenation of zirconium film by implantation of hydrogen ions

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Fang, Kaihong; Lv, Huiyi; Liu, Jiwei; Wang, Boyu

    2017-03-01

    In order to understand the drive-in target in a D-D type neutron generator, it is essential to study the mechanism of the interaction between hydrogen ion beams and the hydrogen-absorbing metal film. The present research concerns the nucleation of hydride within zirconium film implanted with hydrogen ions. Doses of 30 keV hydrogen ions ranging from 4.30 × 1017 to 1.43 × 1018 ions cm-2 were loaded into the zirconium film through the ion beam implantation technique. Features of the surface morphology and transformation of phase structures were investigated with scanning electron microscopy, atomic force microscopy and x-ray diffraction. Confirmation of the formation of δ phase zirconium hydride in the implanted samples was first made by x-ray diffraction, and the different stages in the gradual nucleation and growth of zirconium hydride were then observed by atomic force microscope and scanning electron microscopy.

  3. Development of industrial ion implantation and ion assisted coating processes: A perspective

    NASA Astrophysics Data System (ADS)

    Legg, Keith O.; Solnick-Legg, Hillary

    1989-04-01

    Ion beam processes have gone through a series of developmental stages, from being the mainstay of the semiconductor industry for production of integrated circuits, to new commercial processes for biomedical, aerospace and other industries. Although research is still continuing on surface modification using ion beam methods, ion implantation and ion assisted coatings for treatment of metals, ceramics, polymers and composites must now be considered viable industrial processes of benefit in a wide variety of applications. However, ion implantation methods face various barriers to acceptability, in terms not only of other surface treatment processes, but for implantation itself. This paper will discuss some of the challenges faced by a small company whose primary business is development and marketing of ion implantation and ion-assisted coating processes.

  4. Photosensitivity enhancement of PLZT ceramics by positive ion implantation

    DOEpatents

    Land, Cecil E.; Peercy, Paul S.

    1983-01-01

    The photosensitivity of lead lanthanum zirconate titanate (PLZT) ceramic material used in high resolution, high contrast, and non-volatile photoferroelectric image storage and display devices is enhanced significantly by positive ion implantation of the PLZT near its surface. Implanted ions include H.sup.+, He.sup.+, Ne.sup.+, Ar.sup.+, as well as chemically reactive ions from Fe, Cr, and Al. The positive ion implantation advantageously serves to shift the absorption characteristics of the PLZT material from near-UV light to visible light. As a result, photosensitivity enhancement is such that the positive ion implanted PLZT plate is sensitive even to sunlight and conventional room lighting, such as fluorescent and incandescent light sources. The method disclosed includes exposing the PLZT plate to the positive ions at sufficient density, from 1.times.10.sup.12 to 1.times.10.sup.17, and with sufficient energy, from 100 to 500 KeV, to provide photosensitivity enhancement. The PLZT material may have a lanthanum content ranging from 5 to 10%, a lead zirconate content of 62 to 70 mole %, and a lead titanate content of 38 to 30%. The ions are implanted at a depth of 0.1 to 2 microns below the surface of the PLZT plate.

  5. Charge state defect engineering of silicon during ion implantation

    SciTech Connect

    Brown, R.A.; Ravi, J.; Erokhin, Y.; Rozgonyi, G.A.; White, C.W.

    1997-01-01

    Effects of in situ interventions which alter defect interactions during implantation, and thereby affect the final damage state, have been investigated. Specifically, we examined effects of internal electric fields and charge carrier injection on damage accumulation in Si. First, we implanted H or He ions into diode structures which were either reverse or forward biased during implantation. Second, we implanted B or Si ions into plain Si wafers while illuminating them with UV light. In each case, the overall effect is one of damage reduction. Both the electric field and charge carrier injection effects may be understood as resulting from changes in defect interactions caused in part by changes to the charge state of defects formed during implantation.

  6. The emittance and brightness characteristics of negative ion sources suitable for MeV ion implantation

    SciTech Connect

    Alton, G.D.

    1987-01-01

    This paper provides the description and beam properties of ion sources suitable for use with ion implantation devices. Particular emphasis is placed on the emittance and brightness properties of state-of-the-art, high intensity, negative ion sources based on the cesium ion sputter principle. (WRF)

  7. Surface Engineering of Nanostructured Titanium Implants with Bioactive Ions.

    PubMed

    Kim, H-S; Kim, Y-J; Jang, J-H; Park, J-W

    2016-05-01

    Surface nanofeatures and bioactive ion chemical modification are centrally important in current titanium (Ti) oral implants for enhancing osseointegration. However, it is unclear whether the addition of bioactive ions definitively enhances the osteogenic capacity of a nanostructured Ti implant. We systematically investigated the osteogenesis process of human multipotent adipose stem cells triggered by bioactive ions in the nanostructured Ti implant surface. Here, we report that bioactive ion surface modification (calcium [Ca] or strontium [Sr]) and resultant ion release significantly increase osteogenic activity of the nanofeatured Ti surface. We for the first time demonstrate that ion modification actively induces focal adhesion development and expression of critical adhesion–related genes (vinculin, talin, and RHOA) of human multipotent adipose stem cells, resulting in enhanced osteogenic differentiation on the nanofeatured Ti surface. It is also suggested that fibronectin adsorption may have only a weak effect on early cellular events of mesenchymal stem cells (MSCs) at least in the case of the nanostructured Ti implant surface incorporating Sr. Moreover, results indicate that Sr overrides the effect of Ca and other important surface factors (i.e., surface area and wettability) in the osteogenesis function of various MSCs (derived from human adipose, bone marrow, and murine bone marrow). In addition, surface engineering of nanostructured Ti implants using Sr ions is expected to exert additional beneficial effects on implant bone healing through the proper balancing of the allocation of MSCs between adipogenesis and osteogenesis. This work provides insight into the future surface design of Ti dental implants using surface bioactive ion chemistry and nanotopography.

  8. Fe doped Magnetic Nanodiamonds made by Ion Implantation.

    PubMed

    Chen, ChienHsu; Cho, I C; Jian, Hui-Shan; Niu, H

    2017-02-09

    Here we present a simple physical method to prepare magnetic nanodiamonds (NDs) using high dose Fe ion-implantation. The Fe atoms are embedded into NDs through Fe ion-implantation and the crystal structure of NDs are recovered by thermal annealing. The results of TEM and Raman examinations indicated the crystal structure of the Fe implanted NDs is recovered completely. The SQUID-VSM measurement shows the Fe-NDs possess room temperature ferromagnetism. That means the Fe atoms are distributed inside the NDs without affecting NDs crystal structure, so the NDs can preserve the original physical and chemical properties of the NDs. In addition, the ion-implantation-introduced magnetic property might make the NDs to become suitable for variety of medical applications.

  9. The Behavior of Ion-Implanted Hydrogen in Gallium Nitride

    SciTech Connect

    Myers, S.M.; Headley, T.J.; Hills, C.R.; Han, J.; Petersen, G.A.; Seager, C.H.; Wampler, W.R.

    1999-01-07

    Hydrogen was ion-implanted into wurtzite-phase GaN, and its transport, bound states, and microstructural effects during annealing up to 980 C were investigated by nuclear-reaction profiling, ion-channeling analysis, transmission electron microscopy, and infrared (IR) vibrational spectroscopy. At implanted concentrations 1 at.%, faceted H{sub 2} bubbles formed, enabling identification of energetically preferred surfaces, examination of passivating N-H states on these surfaces, and determination of the diffusivity-solubility product of the H. Additionally, the formation and evolution of point and extended defects arising from implantation and bubble formation were characterized. At implanted H concentrations 0.1 at.%, bubble formation was not observed, and ion-channeling analysis indicated a defect-related H site located within the [0001] channel.

  10. Fe doped Magnetic Nanodiamonds made by Ion Implantation

    NASA Astrophysics Data System (ADS)

    Chen, Chienhsu; Cho, I. C.; Jian, Hui-Shan; Niu, H.

    2017-02-01

    Here we present a simple physical method to prepare magnetic nanodiamonds (NDs) using high dose Fe ion-implantation. The Fe atoms are embedded into NDs through Fe ion-implantation and the crystal structure of NDs are recovered by thermal annealing. The results of TEM and Raman examinations indicated the crystal structure of the Fe implanted NDs is recovered completely. The SQUID-VSM measurement shows the Fe-NDs possess room temperature ferromagnetism. That means the Fe atoms are distributed inside the NDs without affecting NDs crystal structure, so the NDs can preserve the original physical and chemical properties of the NDs. In addition, the ion-implantation-introduced magnetic property might make the NDs to become suitable for variety of medical applications.

  11. Fe doped Magnetic Nanodiamonds made by Ion Implantation

    PubMed Central

    Chen, ChienHsu; Cho, I. C.; Jian, Hui-Shan; Niu, H.

    2017-01-01

    Here we present a simple physical method to prepare magnetic nanodiamonds (NDs) using high dose Fe ion-implantation. The Fe atoms are embedded into NDs through Fe ion-implantation and the crystal structure of NDs are recovered by thermal annealing. The results of TEM and Raman examinations indicated the crystal structure of the Fe implanted NDs is recovered completely. The SQUID-VSM measurement shows the Fe-NDs possess room temperature ferromagnetism. That means the Fe atoms are distributed inside the NDs without affecting NDs crystal structure, so the NDs can preserve the original physical and chemical properties of the NDs. In addition, the ion-implantation-introduced magnetic property might make the NDs to become suitable for variety of medical applications. PMID:28181507

  12. Energetic ion composition of the plasma sheet

    SciTech Connect

    Peterson, W.K.; Sharp, R.D.; Shelley, E.G.; Johnson, R.G.; Balsiger, H.

    1981-02-01

    Data obtained from the energetic ion mass spectrometer experiment on Isee 1 in the distant plasma sheet are presented. These data show that (1) the plasma sheet has a significant and variable ionospheric component (H/sup +/ and O/sup +/) representing from 10% to more than 50% of the total number density and (2) there is more than one process responsible for the energization of solar wind plasma (H/sup +/ and He/sup + +/) to plasma sheet energies.

  13. Energetic ion composition of the plasma sheet

    NASA Technical Reports Server (NTRS)

    Peterson, W. K.; Sharp, R. D.; Shelley, E. G.; Johnson, R. G.; Balsiger, H.

    1981-01-01

    Data obtained from the energetic ion mass spectrometer experiment on Isee 1 in the distant plasma sheet are presented. These data show that (1) the plasma sheet has a significant and variable ionospheric component (H(+) and O(+)) representing from 10% to more than 50% of the total number density and (2) there is more than one process responsible for the energization of solar wind plasma (H(+) and He(++)) to plasma sheet energies.

  14. Hydrogen-induced defects in ion-implanted Si

    NASA Astrophysics Data System (ADS)

    Socher, S.; Lavrov, E. V.; Weber, J.

    2012-09-01

    Single crystalline silicon implanted with 28Si ions and subsequently hydrogenated from an rf plasma at 200∘C is studied by Raman and photoluminescence spectroscopy. A broad Raman band at 3830 cm-1 previously assigned to the rovibrational transitions of hydrogen molecules trapped in Si multivacancies [Ishioka , Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.60.10852 60, 10852 (1999)] reveals a complex line shape at 60 K. In contrast, our study correlates the Raman band to three different localized traps for hydrogen molecules which are identified from the dependence on the ion dose and annealing behavior. Each of these traps, which is saturated with H2, gives rise to three Raman transitions due to para- and ortho-H2. The H2 signals are shown to correlate with the Si-H vibrational modes at 1888, 1930, and 1964 cm-1. Ortho to para conversion rates of H2 at 77 K and room temperature were found to be 62±15 and 8±2 h, respectively.

  15. Chaotic ion motion in magnetosonic plasma waves

    NASA Technical Reports Server (NTRS)

    Varvoglis, H.

    1984-01-01

    The motion of test ions in a magnetosonic plasma wave is considered, and the 'stochasticity threshold' of the wave's amplitude for the onset of chaotic motion is estimated. It is shown that for wave amplitudes above the stochasticity threshold, the evolution of an ion distribution can be described by a diffusion equation with a diffusion coefficient D approximately equal to 1/v. Possible applications of this process to ion acceleration in flares and ion beam thermalization are discussed.

  16. Multifunctions of dual Zn/Mg ion co-implanted titanium on osteogenesis, angiogenesis and bacteria inhibition for dental implants.

    PubMed

    Yu, Yiqiang; Jin, Guodong; Xue, Yang; Wang, Donghui; Liu, Xuanyong; Sun, Jiao

    2017-02-01

    In order to improve the osseointegration and long-term survival of dental implants, it is urgent to develop a multifunctional titanium surface which would simultaneously have osteogeneic, angiogeneic and antibacterial properties. In this study, a potential dental implant material-dual Zn/Mg ion co-implanted titanium (Zn/Mg-PIII) was developed via plasma immersion ion implantation (PIII). The Zn/Mg-PIII surfaces were found to promote initial adhesion and spreading of rat bone marrow mesenchymal stem cells (rBMSCs) via the upregulation of the gene expression of integrin α1 and integrin β1. More importantly, it was revealed that Zn/Mg-PIII could increase Zn(2+) and Mg(2+) concentrations in rBMSCs by promoting the influx of Zn(2+) and Mg(2+) and inhibiting the outflow of Zn(2+), and then could enhance the transcription of Runx2 and the expression of ALP and OCN. Meanwhile, Mg(2+) ions from Zn/Mg-PIII increased Mg(2+) influx by upregulating the expression of MagT1 transporter in human umbilical vein endothelial cells (HUVECs), and then stimulated the transcription of VEGF and KDR via activation of hypoxia inducing factor (HIF)-1α, thus inducing angiogenesis. In addition to this, it was discovered that zinc in Zn/Mg-PIII had certain inhibitory effects on oral anaerobic bacteria (Pg, Fn and Sm). Finally, the Zn/Mg-PIII implants were implanted in rabbit femurs for 4 and 12weeks with Zn-PIII, Mg-PIII and pure titanium as controls. Micro-CT evaluation, sequential fluorescent labeling, histological analysis and push-out test consistently demonstrated that Zn/Mg-PIII implants exhibit superior capacities for enhancing bone formation, angiogenesis and osseointegration, while consequently increasing the bonding strength at bone-implant interfaces. All these results suggest that due to the multiple functions co-produced by zinc and magnesium, rapid osseointegration and sustained biomechanical stability are enhanced by the novel Zn/Mg-PIII implants, which have the potential

  17. Less-Costly Ion Implantation of Solar Cells

    NASA Technical Reports Server (NTRS)

    Fitzgerald, D. J.

    1984-01-01

    Experiments point way toward more relaxed controls over ion-implanation dosage and uniformity in solar-cell fabrication. Data indicate cell performance, measured by output current density at fixed voltage, virtually same whether implant is particular ion species or broad-beam mixture of several species.

  18. Photoreflectance Study of Boron Ion-Implanted (100) Cadmium Telluride

    NASA Technical Reports Server (NTRS)

    Amirtharaj, P. M.; Odell, M. S.; Bowman, R. C., Jr.; Alt, R. L.

    1988-01-01

    Ion implanted (100) cadmium telluride was studied using the contactless technique of photoreflectance. The implantations were performed using 50- to 400-keV boron ions to a maximum dosage of 1.5 x 10(16)/sq cm, and the annealing was accomplished at 500 C under vacuum. The spectral measurements were made at 77 K near the E(0) and E(1) critical points; all the spectra were computer-fitted to Aspnes' theory. The spectral line shapes from the ion damaged, partially recovered and undamaged, or fully recovered regions could be identified, and the respective volume fraction of each phase was estimated.

  19. Photoreflectance Study of Boron Ion-Implanted (100) Cadmium Telluride

    NASA Technical Reports Server (NTRS)

    Amirtharaj, P. M.; Odell, M. S.; Bowman, R. C., Jr.; Alt, R. L.

    1988-01-01

    Ion implanted (100) cadmium telluride was studied using the contactless technique of photoreflectance. The implantations were performed using 50- to 400-keV boron ions to a maximum dosage of 1.5 x 10(16)/sq cm, and the annealing was accomplished at 500 C under vacuum. The spectral measurements were made at 77 K near the E(0) and E(1) critical points; all the spectra were computer-fitted to Aspnes' theory. The spectral line shapes from the ion damaged, partially recovered and undamaged, or fully recovered regions could be identified, and the respective volume fraction of each phase was estimated.

  20. Charging and discharging in ion implanted dielectric films used for capacitive radio frequency microelectromechanical systems switch

    SciTech Connect

    Li Gang; Chen Xuyuan; San Haisheng

    2009-06-15

    In this work, metal-insulator-semiconductor (MIS) capacitor structure was used to investigate the dielectric charging and discharging in the capacitive radio frequency microelectromechanical switches. The insulator in MIS structure is silicon nitride films (SiN), which were deposited by either low pressure chemical vapor deposition (LPCVD) or plasma enhanced chemical vapor deposition (PECVD) processes. Phosphorus or boron ions were implanted into dielectric layer in order to introduce impurity energy levels into the band gap of SiN. The relaxation processes of the injected charges in SiN were changed due to the ion implantation, which led to the change in relaxation time of the trapped charges. In our experiments, the space charges were introduced by stressing the sample electrically with dc biasing. The effects of implantation process on charge accumulation and dissipation in the dielectric are studied by capacitance-voltage (C-V) measurement qualitatively and quantitatively. The experimental results show that the charging and discharging behavior of the ion implanted silicon nitride films deposited by LPCVD is quite different from the one deposited by PECVD. The charge accumulation in the dielectric film can be reduced by ion implantation with proper dielectric deposition method.

  1. Magnesium ion implantation on a micro/nanostructured titanium surface promotes its bioactivity and osteogenic differentiation function.

    PubMed

    Wang, Guifang; Li, Jinhua; Zhang, Wenjie; Xu, Lianyi; Pan, Hongya; Wen, Jin; Wu, Qianju; She, Wenjun; Jiao, Ting; Liu, Xuanyong; Jiang, Xinquan

    2014-01-01

    As one of the important ions associated with bone osseointegration, magnesium was incorporated into a micro/nanostructured titanium surface using a magnesium plasma immersion ion-implantation method. Hierarchical hybrid micro/nanostructured titanium surfaces followed by magnesium ion implantation for 30 minutes (Mg30) and hierarchical hybrid micro/nanostructured titanium surfaces followed by magnesium ion implantation for 60 minutes (Mg60) were used as test groups. The surface morphology, chemical properties, and amount of magnesium ions released were evaluated by field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, field-emission transmission electron microscopy, and inductively coupled plasma-optical emission spectrometry. Rat bone marrow mesenchymal stem cells (rBMMSCs) were used to evaluate cell responses, including proliferation, spreading, and osteogenic differentiation on the surface of the material or in their medium extraction. Greater increases in the spreading and proliferation ability of rBMMSCs were observed on the surfaces of magnesium-implanted micro/nanostructures compared with the control plates. Furthermore, the osteocalcin (OCN), osteopontin (OPN), and alkaline phosphatase (ALP) genes were upregulated on both surfaces and in their medium extractions. The enhanced cell responses were correlated with increasing concentrations of magnesium ions, indicating that the osteoblastic differentiation of rBMMSCs was stimulated through the magnesium ion function. The magnesium ion-implanted micro/nanostructured titanium surfaces could enhance the proliferation, spreading, and osteogenic differentiation activity of rBMMSCs, suggesting they have potential application in improving bone-titanium integration.

  2. Magnesium ion implantation on a micro/nanostructured titanium surface promotes its bioactivity and osteogenic differentiation function

    PubMed Central

    Wang, Guifang; Li, Jinhua; Zhang, Wenjie; Xu, Lianyi; Pan, Hongya; Wen, Jin; Wu, Qianju; She, Wenjun; Jiao, Ting; Liu, Xuanyong; Jiang, Xinquan

    2014-01-01

    As one of the important ions associated with bone osseointegration, magnesium was incorporated into a micro/nanostructured titanium surface using a magnesium plasma immersion ion-implantation method. Hierarchical hybrid micro/nanostructured titanium surfaces followed by magnesium ion implantation for 30 minutes (Mg30) and hierarchical hybrid micro/nanostructured titanium surfaces followed by magnesium ion implantation for 60 minutes (Mg60) were used as test groups. The surface morphology, chemical properties, and amount of magnesium ions released were evaluated by field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, field-emission transmission electron microscopy, and inductively coupled plasma-optical emission spectrometry. Rat bone marrow mesenchymal stem cells (rBMMSCs) were used to evaluate cell responses, including proliferation, spreading, and osteogenic differentiation on the surface of the material or in their medium extraction. Greater increases in the spreading and proliferation ability of rBMMSCs were observed on the surfaces of magnesium-implanted micro/nanostructures compared with the control plates. Furthermore, the osteocalcin (OCN), osteopontin (OPN), and alkaline phosphatase (ALP) genes were upregulated on both surfaces and in their medium extractions. The enhanced cell responses were correlated with increasing concentrations of magnesium ions, indicating that the osteoblastic differentiation of rBMMSCs was stimulated through the magnesium ion function. The magnesium ion-implanted micro/nanostructured titanium surfaces could enhance the proliferation, spreading, and osteogenic differentiation activity of rBMMSCs, suggesting they have potential application in improving bone-titanium integration. PMID:24940056

  3. Ion thruster charge-exchange plasma flow

    NASA Technical Reports Server (NTRS)

    Carruth, M. R., Jr.; Gabriel, S. B.; Kitamura, S.

    1982-01-01

    The electron bombardment ion thruster has been under development for a number of years and during this time, studies of the plasmas produced by the thrusters and their interactions with spacecraft have been evaluated, based on available data. Due to diagnostic techniques used and facility effects, there is uncertainty as to the reliability of data from these early studies. This paper presents data on the flow of the charge-exchange plasma produced just downstream of the thruster's ion optics. The 'end-effect' of a cylindrical Langmuir probe is used to determine ion density and directed ion velocity. Results are compared with data obtained from a retarding potential analyzer-Faraday cup.

  4. Ion temperature anisotropies in Venus plasma environment

    NASA Astrophysics Data System (ADS)

    Stenberg Wieser, Gabriella; Bader, Alexander; Futaana, Yoshifumi; Persson, Moa; André, Mats; Nilsson, Hans

    2017-04-01

    The ion velocity distribution is a key to understanding the interplay between ions in the plasma and the waves. Any deviation from a Maxwellian distribution may be unstable and result in wave generation. We use data from ion mass spectrometer IMA (Ion Mass Analyzer) and the magnetometer MAG onboard Venus Express to investigate what unstable ion distributions are found in the plasma environment of Venus. Especially we examine temperature anisotropies, that is, the difference between the ion temperature parallel and perpendicular to the background magnetic field. Scientific questions addressed include: To what extent does such anisotropies occur? Where in the magnetosphere do they occur? What type of waves would we expect them to generate? We produce spatial maps of the average ratio between the perpendicular and parallel temperatures, both for proton and heavy ions (atomic oxygen, molecular oxygen and carbon dioxide).

  5. Modulating the resistivity of MoS2 through low energy phosphorus plasma implantation

    NASA Astrophysics Data System (ADS)

    Haynes, K.; Murray, R.; Weinrich, Z.; Zhao, X.; Chiappe, D.; Sutar, S.; Radu, I.; Hatem, C.; Perry, S. S.; Jones, K. S.

    2017-06-01

    Molybdenum disulfide (MoS2) is a promising potential replacement for Si in future microelectronic devices. Integration in electronic devices will likely involve the growth or transfer of large-area MoS2 films onto substrates and subsequent isolation of devices. In this paper, the effect of ion implantation on the electrical properties of MoS2 is reported. Large-area ˜4 layer MoS2 films were implanted by low energy phosphorus plasma at biases of 100, 200, and 300 V and a dose of 1 × 1014 cm-2. Electrical measurements using patterned Ni/Au contacts show that after implantation, independent of bias, there is greater than a 104 increase in resistivity. TEM and Raman spectroscopy suggest that the film is crystalline prior to and after ion implantation and annealing and that there is no measurable sputtering following implantation. This suggests that the increase in resistivity is likely the result of radiation damage in the MoS2. The thermal stability of the increase in electrical resistivity was assessed by a series of 15 min anneals beginning at 325 °C in a sulfur overpressure and progressing up to 525 °C under an Al2O3 ALD cap. The resistivity increase remained unchanged after annealing. These results suggest that implant isolation could provide a preferable alternative to reactive ion etching or chemical etching for electrical isolation of MoS2.

  6. Method For Silicon Surface Texturing Using Ion Implantation

    SciTech Connect

    Kadakia, Nirag; Naczas, Sebastian; Bakhru, Hassaram; Huang Mengbing

    2011-06-01

    As the semiconductor industry continues to show more interest in the photovoltaic market, cheaper and readily integrable methods of silicon solar cell production are desired. One of these methods - ion implantation - is well-developed and optimized in all commercial semiconductor fabrication facilities. Here we have developed a silicon surface texturing technique predicated upon the phenomenon of surface blistering of H-implanted silicon, using only ion implantation and thermal annealing. We find that following the H implant with a second, heavier implant markedly enhances the surface blistering, causing large trenches that act as a surface texturing of c-Si. We have found that this method reduces total broadband Si reflectance from 35% to below 5percent;. In addition, we have used Rutherford backscattering/channeling measurements investigate the effect of ion implantation on the crystallinity of the sample. The data suggests that implantation-induced lattice damage is recovered upon annealing, reproducing the original monocrystalline structure in the previously amorphized region, while at the same time retaining the textured surface.

  7. Material synthesis for silicon integrated-circuit applications using ion implantation

    NASA Astrophysics Data System (ADS)

    Lu, Xiang

    As devices scale down into deep sub-microns, the investment cost and complexity to develop more sophisticated device technologies have increased substantially. There are some alternative potential technologies, such as silicon-on-insulator (SOI) and SiGe alloys, that can help sustain this staggering IC technology growth at a lower cost. Surface SiGe and SiGeC alloys with germanium peak composition up to 16 atomic percent are formed using high-dose ion implantation and subsequent solid phase epitaxial growth. RBS channeling spectra and cross-sectional TEM studies show that high quality SiGe and SiGeC crystals with 8 atomic percent germanium concentration are formed at the silicon surface. Extended defects are formed in SiGe and SiGeC with 16 atomic percent germanium concentration. X-ray diffraction experiments confirm that carbon reduces the lattice strain in SiGe alloys but without significant crystal quality improvement as detected by RBS channeling spectra and XTEM observations. Separation by plasma implantation of oxygen (SPIMOX) is an economical method for SOI wafer fabrication. This process employs plasma immersion ion implantation (PIII) for the implantation of oxygen ions. The implantation rate for Pm is considerably higher than that of conventional implantation. The feasibility of SPIMOX has been demonstrated with successful fabrication of SOI structures implementing this process. Secondary ion mass spectrometry (SIMS) analysis and cross-sectional transmission electron microscopy (XTEM) micrographs of the SPIMOX sample show continuous buried oxide under single crystal overlayer with sharp silicon/oxide interfaces. The operational phase space of implantation condition, oxygen dose and annealing requirement has been identified. Physical mechanisms of hydrogen induced silicon surface layer cleavage have been investigated using a combination of microscopy and hydrogen profiling techniques. The evolution of the silicon cleavage phenomenon is recorded by a series

  8. Ion plasma wave and its instability in interpenetrating plasmas

    SciTech Connect

    Vranjes, J.; Kono, M.

    2014-04-15

    Some essential features of the ion plasma wave in both kinetic and fluid descriptions are presented. The wave develops at wavelengths shorter than the electron Debye radius. Thermal motion of electrons at this scale is such that they overshoot the electrostatic potential perturbation caused by ion bunching, which consequently propagates as an unshielded wave, completely unaffected by electron dynamics. So in the simplest fluid description, the electrons can be taken as a fixed background. However, in the presence of magnetic field and for the electron gyro-radius shorter than the Debye radius, electrons can participate in the wave and can increase its damping rate. This is determined by the ratio of the electron gyro-radius and the Debye radius. In interpenetrating plasmas (when one plasma drifts through another), the ion plasma wave can easily become growing and this growth rate is quantitatively presented for the case of an argon plasma.

  9. Retention of ion-implanted-xenon in olivine: Dependence on implantation dose

    NASA Technical Reports Server (NTRS)

    Melcher, C. L.; Tombrello, T. A.; Burnett, D. S.

    1982-01-01

    The diffusion of Xe in olivine, a major mineral in both meteorites and lunar samples, was studied. Xe ions were implanted at 200 keV into single-crystal synthetic-forsterite targets and the depth profiles were measured by alpha particle backscattering before and after annealing for 1 hour at temperatures up to 1500 C. The fraction of implanted Xe retained following annealing was strongly dependent on the implantation dose. Maximum retention of 100% occurred for an implantion dose of 3 x 10 to the 15th power Xe ions/sq cm. Retention was less at lower doses, with (approximately more than or = 50% loss at one hundred trillion Xe ions/sq cm. Taking the diffusion coefficient at this dose as a lower limit, the minimum activation energy necessary for Xe retention in a 10 micrometer layer for ten million years was calculated as a function of metamorphic temperature.

  10. BCA-kMC Hybrid Simulation for Hydrogen and Helium Implantation in Material under Plasma Irradiation

    NASA Astrophysics Data System (ADS)

    Kato, Shuichi; Ito, Atsushi; Sasao, Mamiko; Nakamura, Hiroaki; Wada, Motoi

    2015-09-01

    Ion implantation by plasma irradiation into materials achieves the very high concentration of impurity. The high concentration of impurity causes the deformation and the destruction of the material. This is the peculiar phenomena in the plasma-material interaction (PMI). The injection process of plasma particles are generally simulated by using the binary collision approximation (BCA) and the molecular dynamics (MD), while the diffusion of implanted atoms have been traditionally solved by the diffusion equation, in which the implanted atoms is replaced by the continuous concentration field. However, the diffusion equation has insufficient accuracy in the case of low concentration, and in the case of local high concentration such as the hydrogen blistering and the helium bubble. The above problem is overcome by kinetic Monte Carlo (kMC) which represents the diffusion of the implanted atoms as jumps on interstitial sites in a material. In this paper, we propose the new approach ``BCA-kMC hybrid simulation'' for the hydrogen and helium implantation under the plasma irradiation.

  11. Ion beams from laser-generated plasmas

    NASA Technical Reports Server (NTRS)

    Hughes, R. H.; Anderson, R. J.; Gray, L. G.; Rosenfeld, J. P.; Manka, C. K.; Carruth, M. R.

    1980-01-01

    The paper describes the space-charge-limited beams produced by the plasma blowoffs generated by 20-MW bursts of 1.06-micron radiation from an active Q-switched Nd:YAG laser. Laser power densities near 10 to the 11th/sq cm on solid targets generate thermalized plasma plumes which drift to a 15-kV gridded extraction gap where the ions are extracted, accelerated, and electrostatically focused; the spatially defined ion beams are then magnetically analyzed to determine the charge state content in the beams formed from carbon, aluminum, copper, and lead targets. This technique preserves time-of-flight (TOF) information in the plasma drift region, which permits plasma ion temperatures and mass flow velocities to be determined from the Maxwellian ion curve TOF shapes for the individual charge species.

  12. Antibacterial effect of acrylic dental devices after surface modification by fluorine and silver dual-ion implantation.

    PubMed

    Shinonaga, Yukari; Arita, Kenji

    2012-03-01

    The purpose of the present study was to examine the effectiveness of fluorine and silver ions implanted and deposited into acrylic resin (poly(methyl methacrylate)) using a hybrid process of plasma-based ion implantation and deposition. The surface characteristics were evaluated by X-ray photoelectron spectroscopy (XPS), contact angle measurements, and atomic force microscopy. In addition, an antibacterial activity test was performed by the adenosine-5'-triphosphate luminescence method. XPS spectra of modified specimens revealed peaks due to fluoride and silver. The water contact angle increased significantly due to implantation and deposition of both fluorine and silver ions. In addition, the presence of fluorine and silver was found to inhibit bacterial growth. These results suggest that fluorine and silver dual-ion implantation and deposition can provide antibacterial properties to acrylic medical and dental devices.

  13. Ion acoustic waves in a multi-ion plasma.

    NASA Technical Reports Server (NTRS)

    Fried, B. D.; White, R. B.; Samec, T. K.

    1971-01-01

    An exact treatment of the multispecies ion acoustic dispersion relation is given for an argon/helium plasma. Phase velocity and damping are obtained as a function of ion-electron temperature ratio and relative densities of the two species. There are two important modes in the plasma, with quite different phase velocities, which are referred to as principal heavy ion mode and principal light ion mode. Which of these is dominant depends on the relative densities of the two components, but, in general, the light ion mode becomes important for surprisingly small light ion contamination. Approximate analytic expressions are derived from damping rates and phase velocities and their domains of validity are investigated. Relevance of the results for the investigation of collisionless shocks is discussed.

  14. Ion/water channels for embryo implantation barrier.

    PubMed

    Liu, Xin-Mei; Zhang, Dan; Wang, Ting-Ting; Sheng, Jian-Zhong; Huang, He-Feng

    2014-05-01

    Successful implantation involves three distinct processes, namely the embryo apposition, attachment, and penetration through the luminal epithelium of the endometrium to establish a vascular link to the mother. After penetration, stromal cells underlying the epithelium differentiate and surround the embryo to form the embryo implantation barrier, which blocks the passage of harmful substances to the embryo. Many ion/water channel proteins were found to be involved in the process of embryo implantation. First, ion/water channel proteins play their classical role in establishing a resting membrane potential, shaping action potentials and other electrical signals by gating the flow of ions across the cell membrane. Second, most of ion/water channel proteins are regulated by steroid hormone (estrogen or progesterone), which may have important implications to the embryo implantation. Last but not least, these proteins do not limit themselves as pure channels but also function as an initiator of a series of consequences once activated by their ligand/stimulator. Herein, we discuss these new insights in recent years about the contribution of ion/water channels to the embryo implantation barrier construction during early pregnancy.

  15. Biofunctionalization of surfaces by energetic ion implantation: Review of progress on applications in implantable biomedical devices and antibody microarrays

    NASA Astrophysics Data System (ADS)

    Bilek, Marcela M. M.

    2014-08-01

    Despite major research efforts in the field of biomaterials, rejection, severe immune responses, scar tissue and poor integration continue to seriously limit the performance of today's implantable biomedical devices. Implantable biomaterials that interact with their host via an interfacial layer of active biomolecules to direct a desired cellular response to the implant would represent a major and much sought after improvement. Another, perhaps equally revolutionary, development that is on the biomedical horizon is the introduction of cost-effective microarrays for fast, highly multiplexed screening for biomarkers on cell membranes and in a variety of analyte solutions. Both of these advances will rely on effective methods of functionalizing surfaces with bioactive molecules. After a brief introduction to other methods currently available, this review will describe recently developed approaches that use energetic ions extracted from plasma to facilitate simple, one-step covalent surface immobilization of bioactive molecules. A kinetic theory model of the immobilization process by reactions with long-lived, mobile, surface-embedded radicals will be presented. The roles of surface chemistry and microstructure of the ion treated layer will be discussed. Early progress on applications of this technology to create diagnostic microarrays and to engineer bioactive surfaces for implantable biomedical devices will be reviewed.

  16. Ion Implantation Effects on the Metal-Semiconductor Interfaces.

    NASA Astrophysics Data System (ADS)

    Yapsir, Andrie Setiawan

    1988-12-01

    In this thesis, the effects of ion implantation on metal-semiconductor interfaces are studied. Hydrogen ions have been used as the implanted species. The implantation is carried out on Al/n-Si Schottky contacts. Electrical characterizations, deep level transient spectroscopy measurements, and the ^{15}N hydrogen profiling technique have been used to study the effects of ion implantation. It is demonstrated that the defect centers in the depletion region created by hydrogen implantation have more likely negative or possibly neutral signatures, rather than a positive signature as has been previously speculated. These negatively charged centers compensate for the positive donor resulting in a widening of the depletion region and reduction in the capacitance of the metal-semiconductor contacts. The tendency of hydrogen to passivate its own damage which results in the recovery of electronic transport across the metal-semiconductor junction upon low temperature heat treatment is also demonstrated. In connection with the behavior of hydrogen in silicon, in the second part of this thesis, detailed theoretical calculations on the hydrogen passivation of defects in silicon are carried out. A particular type of defect, namely, a substitutional sulfur in silicon, is chosen and is studied using the modified intermediate neglect of differential overlap (MINDO/3) molecular orbital method. It is found that the sulfur center can be passivated using one or two hydrogen atoms. The calculations indicate that the most stable positions of the hydrogen atoms are between the sulfur and its silicon neighbors. The hydrogens bond to the nearest silicon atoms and only weakly interact with the sulfur. Thermochemistry considerations predict that a single hydrogen passivates the sulfur center, provided these centers are in abundance in the silicon. Hydrogen ion implantation has also been carried out on Schottky contacts having a large difference in metal work function, Ti/p-Si and Pt

  17. Surface modification of SKD-61 steel by ion implantation technique

    SciTech Connect

    Wen, F. L.; Lo, Y.-L.; Yu, Y.-C.

    2007-07-15

    The purpose of this study is to investigate how ion implantation affects the surface characteristics and nitrogenizing depth of the thin film by the use of a NEC 9SDH-2 3 MV Pelletron accelerator that implants nitrogen ions into SKD-61 tool steels for surface modification. Nitrogen ions were implanted into the surface layer of materials so that the hardness of modified films could be improved. Also, the nitride film stripping problems of the traditional nitrogenizing treatment could be overcome by a new approach in surface process engineering. As nitrogen ions with high velocity impacted on the surface of the substrate, the ions were absorbed and accumulated on the surface of the substrate. The experiments were performed with two energies (i.e., 1 and 2 MeV) and different doses (i.e., 2.5x10{sup 15}, 7.5x10{sup 15}, and 1.5x10{sup 16} ions/cm{sup 2}). Nitrogen ions were incorporated into the interface and then diffused through the metal to form a nitride layer. Analysis tools included the calculation of stopping and range of ions in matter (SRIM), the detection of a secondary ion mass spectrometry (SIMS), and nanoindentation testing. Through the depth analysis of SIMS, the effects of the ion-implanted SKD-61 steels after heating at 550 deg. C in a vacuum furnace were examined. The nanoindenting results indicate the variation of hardness of SKD-61 steels with the various ion doses. It reaches two to three times the original hardness of SKD-61 steels.

  18. Study of the plasma immersion implantation of titanium in stainless steel

    NASA Astrophysics Data System (ADS)

    Nikitenkov, N. N.; Sutygina, A. N.; Shulepov, I. A.; Sivin, D. O.; Kashkarov, E. B.

    2015-04-01

    The results of the study of the pulsed plasma-immersion ion implantation of titanium in steel Cr18Ni10Ti depending on the time (dose) implantation are presented. It is shown that the change of the element and the phase composition of the surface layers and their microscopic characteristics and mechanical properties (hardness, wear resistance) depending on the implantation time is not monotonic, but follows to a certain rule. The possibility of interpretation of the obtained results in the thermal spike concept of the generation on the surface by the stable (magic) clusters is discussed. This concept follows logically from the recent studies on the plasma arc composition and from a polyatomic clusters-surface interaction.

  19. Osteoconductivity of hydrophilic microstructured titanium implants with phosphate ion chemistry.

    PubMed

    Park, Jin-Woo; Jang, Je-Hee; Lee, Chong Soo; Hanawa, Takao

    2009-07-01

    This study investigated the surface characteristics and bone response of titanium implants produced by hydrothermal treatment using H(3)PO(4), and compared them with those of implants produced by commercial surface treatment methods - machining, acid etching, grit blasting, grit blasting/acid etching or spark anodization. The surface characteristics were evaluated by scanning electron microscopy, thin-film X-ray diffractometry, X-ray photoelectron spectroscopy, contact angle measurement and stylus profilometry. The osteoconductivity of experimental implants was evaluated by removal torque testing and histomorphometric analysis after 6 weeks of implantation in rabbit tibiae. Hydrothermal treatment with H(3)PO(4) and subsequent heat treatment produced a crystalline phosphate ion-incorporated oxide (titanium oxide phosphate hydrate, Ti(2)O(PO(4))(2)(H(2)O)(2); TiP) surface approximately 5microm in thickness, which had needle-like surface microstructures and superior wettability compared with the control surfaces. Significant increases in removal torque forces and bone-to-implant contact values were observed for TiP implants compared with those of the control implants (p<0.001). After thorough cleaning of the implants removed during the removal torque testing, a considerable quantity of attached bone was observed on the surfaces of the TiP implants.

  20. Evolution of ion-acoustic plasma turbulence

    NASA Astrophysics Data System (ADS)

    Bychenkov, V. Iu.; Gradov, O. M.

    1986-03-01

    The evolution of ion-acoustic turbulence is studied on the basis of a numerical solution of the nonstationary equation for in-acoustic waves. Consideration is given to conditions under which the excitation threshold of long-wave ion-acoustic oscillations is exceeded as the result of instability saturation due to quasi-linear relaxation of electrons on turbulent pulsations and the induced scattering of ions by the ion sound. Distributed spectra of ion-acoustic turbulence are established in the plasma under these conditions.

  1. Ion beam parameters of a plasma accelerator

    SciTech Connect

    Nazarov, V.G.; Vinogradov, A.M.; Veselovzorov, A.N.; Efremov, V.K.

    1987-08-01

    The aim of this investigation was to determine the dependences of the current density, the energy, and the divergence of the ion beams of an UZDP-type source (a plasma accelerator with closed electron drift in the accelerator channel and an extended zone of ion acceleration) on the parameters which determine its performance, and to establish qualitative relationships between these values.

  2. Plasma ion stratification by weak planar shocks

    NASA Astrophysics Data System (ADS)

    Simakov, Andrei N.; Keenan, Brett D.; Taitano, William T.; Chacón, Luis

    2017-09-01

    We derive fluid equations for describing steady-state planar shocks of a moderate strength ( 0 plasma comprising two separate ion species. In addition to the standard fluid shock quantities, such as the total mass density, mass-flow velocity, and electron and average ion temperatures, the equations describe shock stratification in terms of variations in the relative concentrations and temperatures of the two ion species along the shock propagation direction. We have solved these equations analytically for weak shocks ( 0 ion masses and charges, and the upstream mass fraction of one of the ion species. These analytical results are instrumental for gaining understanding of the behavior of weak shocks, and they have been used to verify kinetic simulations of shocks in multi-ion plasmas.

  3. Ion implantation of diamond: Damage, doping, and lift-off

    SciTech Connect

    Parikh, N.R.; McGucken, E.; Swanson, M.L.; Hunn, J.D.; White, C.W.; Zuhr, R.A.

    1993-09-01

    In order to make good quality economical diamond electronic devices, it is essential to grow films and to dope these films to obtain n- and p- type conductivity. This review talk discuss first doping by ion implantation plus annealing of the implantation damage, and second flow to make large area single crystal diamonds. C implantation damage below an estimated Frenkel defect concentration of 7% could be recovered almost completely by annealing at 950C. For a defect concentration between 7 and 10%, a stable damage form of diamond (``green diamond``) was formed by annealing. At still higher damage levels, the diamond graphitized. To introduce p-type doping, we have co-implanted B and C into natural diamond at 77K, followed by annealing up to 1100C. The resulting semiconducting material has electrical properties similar to those of natural B-doped diamond. To create n-type diamond, we have implanted Na{sup +}, P+ and As{sup +} ions and have observed semiconducting behavior. This has been compared with carbon or noble element implantation, in an attempt to isolate the effect of radiation damage. Recently, in order to obtain large area signal crystals, we have developed a novel technique for removing thin layers of diamond from bulk or homoepitaxial films. This method consists of ion implantation, followed by selective etching. High energy (4--5 MeV) implantation of carbon or oxygen ions creates a well-defined layer of damaged diamond buried at a controlled depth. This layer is graphitized and selectivity etched either by heating at 550C in an oxygen ambient or by electrolysis. This process successfully lifts off the diamond plate above the graphite layer. The lift-off method, combined with well-established homoepitaxial growth processes, has potential for fabrication of large area single-crystal diamond sheets.

  4. Ion implanted junctions for silicon space solar cells

    NASA Technical Reports Server (NTRS)

    Spitzer, M. B.; Sanfacon, M. M.; Wolfson, R. G.

    1983-01-01

    This paper reviews the application of ion implantation to emitter and back surface field formation in silicon space solar cells. Experiments based on 2 ohm-cm boron-doped silicon are presented. It is shown that the implantation process is particularly compatible with formation of a high-quality back surface reflector. Large area solar cells with AM0 efficiency greater than 14 percent are reported.

  5. N + surface doping on nanoscale polymer fabrics via ion implantation

    NASA Astrophysics Data System (ADS)

    Ho Wong, Kenneth Kar; Zinke-Allmang, Martin; Wan, Wankei

    2006-08-01

    Non-woven poly(vinyl alcohol) (PVA) fabrics composed of small diameter (∼110 nm) fibers have been spun by an electrospinning technique and then have been modified by ion implantation. 1.7 MeV N+ ion implantation with a dose of 1.2 × 1016 ions/cm2 was applied on the fabrics through a metal foil at room temperature. By using scanning electron microscopy (SEM), no surface morphology degradation has been observed on the fabric after the ion beam treatment. The diameter of the fibers has shrunk by 30% to about 74 nm. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) show that nitrogen surface doping was achieved and the formation of two new functional chemical groups (N-Cdbnd O and C-N) in the PVA is observed.

  6. Planar InAs photodiodes fabricated using He ion implantation.

    PubMed

    Sandall, Ian; Tan, Chee Hing; Smith, Andrew; Gwilliam, Russell

    2012-04-09

    We have performed Helium (He) ion implantation on InAs and performed post implant annealing to investigate the effect on the sheet resistance. Using the transmission line model (TLM) we have shown that the sheet resistance of a p⁺ InAs layer, with a nominal doping concentration of 1x10¹⁸ cm⁻³, can increase by over 5 orders of magnitude upon implantation. We achieved a sheet resistance of 1x10⁵ Ω/Square in an 'as-implanted' sample and with subsequent annealing this can be further increased to 1x10⁷ Ω/Square. By also performing implantation on p-i-n structures we have shown that it is possible to produce planar photodiodes with comparable dark currents and quantum efficiencies to chemically etched reference mesa InAs photodiodes.

  7. Compression of self-ion implanted iron micropillars

    NASA Astrophysics Data System (ADS)

    Grieveson, E. M.; Armstrong, D. E. J.; Xu, S.; Roberts, S. G.

    2012-11-01

    Ion implantation causes displacement damage in materials, leading to the formation of small dislocation loops and can cause changes to the material's mechanical properties. Samples of pure Fe were subjected to Fe+ implantation at 275 °C, producing damage of ˜6 dpa to ˜1 μm depth. Nanoindentation into implanted material shows an increase in hardness compared to unimplanted material. Micropillars were manufactured in cross-section specimens of implanted and unimplanted material and compressed using a nanoindenter. The implanted pillars have a deformation mode which differs markedly from the unimplanted pillars but show no change in yield-stress. This suggests that the controlling mechanism for deformation is different between nanoindentation and micropillar compression and that care is needed if using micropillar compression to extract bulk properties of irradiated materials.

  8. Laser plasma as an effective ion source

    NASA Astrophysics Data System (ADS)

    Masek, Karel; Krasa, Josef; Laska, Leos; Pfeifer, Miroslav; Rohlena, Karel; Kralikova, Bozena; Skala, Jiri; Woryna, Eugeniusz; Farny, J.; Parys, Piotr; Wolowski, Jerzy; Mraz, W.; Haseroth, H.; Sharkov, B.; Korschinek, G.

    1998-09-01

    Ions in different charge state and with different energy distribution are generated in the process of interaction of intense laser radiation with solid targets. Multiply charged ions of medium- and high-Z elements (Al, Co, Ni, Cu, Sn, Ta, W, Pt, Au, Pb, Bi), produced by photodissociation iodine laser system PERUN ((lambda) equals 1.315 micrometer, EL approximately 40 J, (tau) approximately 500 ps) are reported. Corpuscular diagnostics based on time-of-flight method (ion collectors and a cylindrical electrostatic ion energy analyzer) as well as Thomson parabola spectrometer were used in the experiments. The ions in maximum charge state up to about 55+ and with energies of several MeV were registered at a distance of about 2 m from the plasma plume. Measured ion current densities higher than 10 mA/cm2 in about 1 m from the target demonstrate the performance of laser ion source. A theoretical interpretation of ion spectra is attempted.

  9. The effect of plasma surface treatment on the bioactivity of titanium implant materials (in vitro)

    PubMed Central

    Abdelrahim, Ramy A.; Badr, Nadia A.; Baroudi, Kusai

    2016-01-01

    Background: The surface of an implantable biomaterial plays a very important role in determining the biocompatibility, osteoinduction, and osteointegration of implants because it is in intimate contact with the host bone and soft tissues. Objective: This study was aimed to assess the effect of plasma surface treatment on the bioactivity of titanium alloy (Ti–6Al–4V). Materials and Methods: Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (with five samples in each group). Five samples were kept untreated and served as control (group A). Another five plasma samples were sprayed for nitrogen ion implantation on their surfaces (group B) and the last five samples were pre-etched with acid before plasma treatment (group C). All the investigated samples were immersed for 7 days in Hank's balanced salt solution (HBSS) which was used as a simulating body fluid (SBF) at pH 7.4 and 37°C. HBSS was renewed every 3 days. The different surfaces were characterized by X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXA), and Fourier Transformation Infrared Spectroscopy (FTIR). Results: Nitriding of Ti-alloy samples via plasma nitrogen ion implantation increased the bioactivity of titanium. Moreover, the surface topography affected the chemical structure of the formed apatite. Increasing the surface roughness enhanced the bioactivity of the implant material. Conclusions: Nitridation can be exploited as an effective way to promote the formation of bone-like material on the implant surface. PMID:27011927

  10. Observations of Ag diffusion in ion implanted SiC

    NASA Astrophysics Data System (ADS)

    Gerczak, Tyler J.; Leng, Bin; Sridharan, Kumar; Hunter, Jerry L.; Giordani, Andrew J.; Allen, Todd R.

    2015-06-01

    The nature and magnitude of Ag diffusion in SiC has been a topic of interest in connection with the performance of tristructural isotropic (TRISO) coated particle fuel for high temperature gas-cooled nuclear reactors. Ion implantation diffusion couples have been revisited to continue developing a more complete understanding of Ag fission product diffusion in SiC. Ion implantation diffusion couples fabricated from single crystal 4H-SiC and polycrystalline 3C-SiC substrates and exposed to 1500-1625 °C, were investigated by transmission electron microscopy and secondary ion mass spectrometry (SIMS). The high dynamic range of SIMS allowed for multiple diffusion régimes to be investigated, including enhanced diffusion by implantation-induced defects and grain boundary (GB) diffusion in undamaged SiC. Estimated diffusion coefficients suggest GB diffusion in bulk SiC does not properly describe the release observed from TRISO fuel.

  11. Ion implantation of graphene-toward IC compatible technologies.

    PubMed

    Bangert, U; Pierce, W; Kepaptsoglou, D M; Ramasse, Q; Zan, R; Gass, M H; Van den Berg, J A; Boothroyd, C B; Amani, J; Hofsäss, H

    2013-10-09

    Doping of graphene via low energy ion implantation could open possibilities for fabrication of nanometer-scale patterned graphene-based devices as well as for graphene functionalization compatible with large-scale integrated semiconductor technology. Using advanced electron microscopy/spectroscopy methods, we show for the first time directly that graphene can be doped with B and N via ion implantation and that the retention is in good agreement with predictions from calculation-based literature values. Atomic resolution high-angle dark field imaging (HAADF) combined with single-atom electron energy loss (EEL) spectroscopy reveals that for sufficiently low implantation energies ions are predominantly substitutionally incorporated into the graphene lattice with a very small fraction residing in defect-related sites.

  12. Ion implantation for manufacturing bent and periodically bent crystals

    SciTech Connect

    Bellucci, Valerio; Camattari, Riccardo; Guidi, Vincenzo Mazzolari, Andrea; Paternò, Gianfranco; Lanzoni, Luca

    2015-08-10

    Ion implantation is proposed to produce self-standing bent monocrystals. A Si sample 0.2 mm thick was bent to a radius of curvature of 10.5 m. The sample curvature was characterized by interferometric measurements; the crystalline quality of the bulk was tested by X-ray diffraction in transmission geometry through synchrotron light at ESRF (Grenoble, France). Dislocations induced by ion implantation affect only a very superficial layer of the sample, namely, the damaged region is confined in a layer 1 μm thick. Finally, an elective application of a deformed crystal through ion implantation is here proposed, i.e., the realization of a crystalline undulator to produce X-ray beams.

  13. Observations of Ag diffusion in ion implanted SiC

    SciTech Connect

    Gerczak, Tyler J.; Leng, Bin; Sridharan, Kumar; Jerry L. Hunter, Jr.; Giordani, Andrew J.; Allen, Todd R.

    2015-03-17

    The nature and magnitude of Ag diffusion in SiC has been a topic of interest in connection with the performance of tristructural isotropic (TRISO) coated particle fuel for high temperature gas-cooled nuclear reactors. Ion implantation diffusion couples have been revisited to continue developing a more complete understanding of Ag fission product diffusion in SiC. Ion implantation diffusion couples fabricated from single crystal 4H-SiC and polycrystalline 3C-SiC substrates and exposed to 1500–1625°C, were investigated in this study by transmission electron microscopy and secondary ion mass spectrometry (SIMS). The high dynamic range of SIMS allowed for multiple diffusion régimes to be investigated, including enhanced diffusion by implantation-induced defects and grain boundary (GB) diffusion in undamaged SiC. Lastly, estimated diffusion coefficients suggest GB diffusion in bulk SiC does not properly describe the release observed from TRISO fuel.

  14. Estimation of nitrogen ion energy calculated using distribution for nitrogen in Si implanted by PBII

    NASA Astrophysics Data System (ADS)

    Tanaka, T.; Watanabe, S.; Takagi, T.

    2006-01-01

    Plasma-based ion implantation (PBII) using N2 gas is examined as a sterilization technique for three-dimensional targets. The application of a pulsed negative voltage (5 μs pulse width, 300 pulses/s, -800 V to -13 kV) at an N2 gas pressure of 2.4 Pa is shown to reduce the number of Bacillus pumilus survivors by up to 105 times after just 5 min of exposure. The energy of nitrogen ions is calculated based on the depth profile of nitrogen concentration in Si implanted by PBII, and it is revealed that the actual nitrogen ion energy is much lower than that calculated based on the voltage applied during processing.

  15. Mass flow facilitates tungsten blistering under 60 keV helium ion implantation

    NASA Astrophysics Data System (ADS)

    Han, Wenjia; Yu, Jiangang; Chen, Zhe; Lu, Guanghong; Zhu, Kaigui

    2017-07-01

    Gaseous ion implantation induces displacement damage and gaseous atom uptake in the target material and is widely adopted to simulate plasma-material interaction in fusion devices. Here we report an observation of tungsten blistering with large plastic deformation under 60 keV helium ion implantation at room temperature. The near-surface morphology and microstructure analyses suggest more than 50% plastic elongation and breakdown of lattice periodicity in the blister caps. We propose that collision cascades and high-concentration helium atoms not only greatly modify the tungsten microstructure, but also enhance mass flow in terms of point defect diffusion in blister caps. The mass flow ultimately aggravates the relaxation of stresses in the tungsten surface and facilitates tungsten blistering during high-energy gaseous ion implantation. We sketch out the blistering process and stress the vital importance of dynamic processes in the response of plasma-facing materials subjected to low-energy plasma penetration and high-energy neutron bombardment in fusion devices.

  16. Ion Implanted Passivated Contacts for Interdigitated Back Contacted Solar Cells

    SciTech Connect

    Young, David L.; Nemeth, William; LaSalvia, Vincenzo; Reedy, Robert; Bateman, Nicholas; Stradins, Pauls

    2015-06-14

    We describe work towards an interdigitated back contacted (IBC) solar cell utilizing ion implanted, passivated contacts. Formation of electron and hole passivated contacts to n-type CZ wafers using tunneling SiO2 and ion implanted amorphous silicon (a-Si) are described. P and B were ion implanted into intrinsic amorphous Si films at several doses and energies. A series of post-implant anneals showed that the passivation quality improved with increasing annealing temperatures up to 900 degrees C. The recombination parameter, Jo, as measured by a Sinton lifetime tester, was Jo ~ 14 fA/cm2 for Si:P, and Jo ~ 56 fA/cm2 for Si:B contacts. The contact resistivity for the passivated contacts, as measured by TLM patterns, was 14 milliohm-cm2 for the n-type contact and 0.6 milliohm-cm2 for the p-type contact. These Jo and pcontact values are encouraging for forming IBC cells using ion implantation to spatially define dopants.

  17. Ion implantation of CdTe single crystals

    NASA Astrophysics Data System (ADS)

    Wiecek, Tomasz; Popovich, Volodymir; Bester, Mariusz; Kuzma, Marian

    2016-12-01

    Ion implantation is a technique which is widely used in industry for unique modification of metal surface for medical applications. In semiconductor silicon technology ion implantation is also widely used for thin layer electronic or optoelectronic devices production. For other semiconductor materials this technique is still at an early stage. In this paper based on literature data we present the main features of the implantation of CdTe single crystals as well as some of the major problems which are likely to occur when dealing with them. The most unexpected feature is the high resistance of these crystals against the amorphization caused by ion implantation even at high doses (1017 1/cm2). The second property is the disposal of defects much deeper in the sample then it follows from the modeling calculations. The outline of principles of the ion implantation is included in the paper. The data based on RBS measurements and modeling results obtained by using SRIM software were taken into account.

  18. Ion response in a weakly ionized plasma with ion flow

    SciTech Connect

    Kompaneets, Roman; Tyshetskiy, Yuriy O.; Vladimirov, Sergey V.

    2013-04-15

    We study the ion response to an initial perturbation in a weakly ionized plasma with ion flow driven by a dc electric field. The analysis is made by extending the classical Landau work [J. Phys. (USSR) 10, 25 (1946)] to the ion kinetic equation including ion-neutral collisions and a dc electric field. We show, in particular, that the complex frequencies of ion waves can be directly found from a known expression for the ion susceptibility [A. V. Ivlev et al., Phys. Rev. E 71, 016405 (2005); V. A. Schweigert, Phys. Rep. 27, 997 (2001)]; this is not obvious from its original derivation, because it only aims to describe the ion response for real frequencies.

  19. High frequency plasma generator for ion thrusters

    NASA Technical Reports Server (NTRS)

    Goede, H.; Divergilio, W. F.; Fosnight, V. V.; Komatsu, G.

    1984-01-01

    The results of a program to experimentally develop two new types of plasma generators for 30 cm electrostatic argon ion thrusters are presented. The two plasma generating methods selected for this study were by radio frequency induction (RFI), operating at an input power frequency of 1 MHz, and by electron cyclotron heating (ECH) at an operating frequency of 5.0 GHz. Both of these generators utilize multiline cusp permanent magnet configurations for plasma confinement and beam profile optimization. The program goals were to develop a plasma generator possessing the characteristics of high electrical efficiency (low eV/ion) and simplicity of operation while maintaining the reliability and durability of the conventional hollow cathode plasma sources. The RFI plasma generator has achieved minimum discharge losses of 120 eV/ion while the ECH generator has obtained 145 eV/ion, assuming a 90% ion optical transparency of the electrostatic acceleration system. Details of experimental tests with a variety of magnet configurations are presented.

  20. Characterization of a Bernas ion source for multiply charged ion implantation

    NASA Astrophysics Data System (ADS)

    Walther, S. R.

    1994-04-01

    Due to concerns about energy purity and reduced beam current, the use of multiply charged ions to achieve higher effective ion energies with a fixed acceleration potential has not been common for implantation users in the semiconductor industry. Energy purity is compromised primarily by charge exchange in the implanter beamline, caused by neutral gas originating from the ion source extraction aperture. Beam current has been an issue, since traditional implanter ion sources, such as the Freeman source, produce very limited currents of multiply charged species. At low beam currents, the implanter is not economical to use, hence the lack of commercial use of multiply charged ion implantation. Ion sources that address these issues must also meet requirements for adequate source lifetime, simplicity of operation (for computer control) and maintenance, and low cost of ownership. This paper details beam energy purity and usable beam currents for a new medium current Bernas ion source as compared to a standard Freeman ion source. The results show significant performance improvements, while also increasing the ion source lifetime.

  1. Ion Implanted GaAs I.C. Process Technology

    DTIC Science & Technology

    1981-07-01

    in ion implantation in GaAs, coupled with better control of the substrate material. 1 Once ion implantation became a reliable processing technology it... Processing Technology for Planar GaAs Integrated Circuits," GaAs IC Symposium, Lake Tahoe, CA., Sept. 1979. 20. R.C. Eden, "GaAs Integrated Circuit Device...1980. 25. B.M. Welch, "Advances in GaAs LSI!VLSI Processing Technology ," Sol. St. Tech., Feb. 1980, pp. 95-101. 27. R. Zucca, B.M. Welch, P.M

  2. A micro-structured ion-implanted magnonic crystal

    SciTech Connect

    Obry, Bjoern; Pirro, Philipp; Chumak, Andrii V.; Ciubotaru, Florin; Serga, Alexander A.; Hillebrands, Burkard; Braecher, Thomas; Osten, Julia; Fassbender, Juergen

    2013-05-20

    We investigate spin-wave propagation in a microstructured magnonic-crystal waveguide fabricated by localized ion implantation. The irradiation caused a periodic variation in the saturation magnetization along the waveguide. As a consequence, the spin-wave transmission spectrum exhibits a set of frequency bands, where spin-wave propagation is suppressed. A weak modification of the saturation magnetization by 7% is sufficient to decrease the spin-wave transmission in the band gaps by a factor of 10. These results evidence the applicability of localized ion implantation for the fabrication of efficient micron- and nano-sized magnonic crystals for magnon spintronic applications.

  3. Temperature Activated Diffusion of Radicals through Ion Implanted Polymers.

    PubMed

    Wakelin, Edgar A; Davies, Michael J; Bilek, Marcela M M; McKenzie, David R

    2015-12-02

    Plasma immersion ion implantation (PIII) is a promising technique for immobilizing biomolecules on the surface of polymers. Radicals generated in a subsurface layer by PIII treatment diffuse throughout the substrate, forming covalent bonds to molecules when they reach the surface. Understanding and controlling the diffusion of radicals through this layer will enable efficient optimization of this technique. We develop a model based on site to site diffusion according to Fick's second law with temperature activation according to the Arrhenius relation. Using our model, the Arrhenius exponential prefactor (for barrierless diffusion), D0, and activation energy, EA, for a radical to diffuse from one position to another are found to be 3.11 × 10(-17) m(2) s(-1) and 0.31 eV, respectively. The model fits experimental data with a high degree of accuracy and allows for accurate prediction of radical diffusion to the surface. The model makes useful predictions for the lifetime over which the surface is sufficiently active to covalently immobilize biomolecules and it can be used to determine radical fluence during biomolecule incubation for a range of storage and incubation temperatures so facilitating selection of the most appropriate parameters.

  4. The Optical Properties of Ion Implanted Silica

    NASA Technical Reports Server (NTRS)

    Smith, Cydale C.; Ila, D.; Sarkisov, S.; Williams, E. K.; Poker, D. B.; Hensley, D. K.

    1997-01-01

    We will present our investigation on the change in the optical properties of silica, 'suprasil', after keV through MeV implantation of copper, tin, silver and gold and after annealing. Suprasil-1, name brand of silica glass produced by Hereaus Amerisil, which is chemically pure with well known optical properties. Both linear nonlinear optical properties of the implanted silica were investigated before and after thermal annealing. All implants, except for Sn, showed strong optical absorption bands in agreement with Mie's theory. We have also used Z-scan to measure the strength of the third order nonlinear optical properties of the produced thin films, which is composed of the host material and the metallic nanoclusters. For implants with a measurable optical absorption band we used Doyle's theory and the full width half maximum of the absorption band to calculate the predicted size of the formed nanoclusters at various heat treatment temperatures. These results are compared with those obtained from direct observation using transmission electron microscopic techniques.

  5. The Optical Properties of Ion Implanted Silica

    NASA Technical Reports Server (NTRS)

    Smith, Cydale C.; Ila, D.; Sarkisov, S.; Williams, E. K.; Poker, D. B.; Hensley, D. K.

    1997-01-01

    We will present our investigation on the change in the optical properties of silica, 'suprasil', after keV through MeV implantation of copper, tin, silver and gold and after annealing. Suprasil-1, name brand of silica glass produced by Hereaus Amerisil, which is chemically pure with well known optical properties. Both linear nonlinear optical properties of the implanted silica were investigated before and after thermal annealing. All implants, except for Sn, showed strong optical absorption bands in agreement with Mie's theory. We have also used Z-scan to measure the strength of the third order nonlinear optical properties of the produced thin films, which is composed of the host material and the metallic nanoclusters. For implants with a measurable optical absorption band we used Doyle's theory and the full width half maximum of the absorption band to calculate the predicted size of the formed nanoclusters at various heat treatment temperatures. These results are compared with those obtained from direct observation using transmission electron microscopic techniques.

  6. Analytical electron microscopy of aluminum ion-implanted with molybdenum

    SciTech Connect

    Stephenson, L.D.; Bentley, J.; Benson, R.B. Jr.; Parrish, P.A.

    1983-01-01

    The microstructures of aluminum ion-implanted with molybdenum and subjected to various heat treatments were investigated for correlation with near-surface properties such as corrosion. Previous work indicated enhanced corrosion resistance, but dealt chiefly with the as-implanted condition and involved little microstructural characterization. In addition, the Al-Mo binary system is of interest because metastable phase formation was considered to be possible and the equilibrium phase diagram is poorly defined. Electropolished coupons 38 x 28 x 0.5 mm of 99.999% Al with approx.0.5 mm grain size were implanted with Mo/sup +/ ions at the Naval Research Laboratory. The dual energy implant schedule of 4.88 x 10/sup 19/ ions/m/sup 2/ at 50 keV plus 6.14 x 10/sup 19/ ions/m/sup 2/ at 110 keV resulted in a peak concentration of 4.4 at. % Mo (measured by ion backscattering) within the projected range of approx.50 nm. Results of the studies are presented.

  7. Dislocation mechanism of deuterium retention in tungsten under plasma implantation.

    PubMed

    Dubinko, V I; Grigorev, P; Bakaev, A; Terentyev, D; van Oost, G; Gao, F; Van Neck, D; Zhurkin, E E

    2014-10-01

    We have developed a new theoretical model for deuterium (D) retention in tungsten-based alloys on the basis of its being trapped at dislocations and transported to the surface via the dislocation network with parameters determined by ab initio calculations. The model is used to explain experimentally observed trends of D retention under sub-threshold implantation, which does not produce stable lattice defects to act as traps for D in conventional models. Saturation of D retention with implantation dose and effects due to alloying of tungsten with, e.g. tantalum, are evaluated, and comparison of the model predictions with experimental observations under high-flux plasma implantation conditions is presented.

  8. Corrosion resistance of titanium ion implanted AZ91 magnesium alloy

    SciTech Connect

    Liu Chenglong; Xin Yunchang; Tian Xiubo; Zhao, J.; Chu, Paul K.

    2007-03-15

    Degradable metal alloys constitute a new class of materials for load-bearing biomedical implants. Owing to their good mechanical properties and biocompatibility, magnesium alloys are promising in degradable prosthetic implants. The objective of this study is to improve the corrosion behavior of surgical AZ91 magnesium alloy by titanium ion implantation. The surface characteristics of the ion implanted layer in the magnesium alloys are examined. The authors' results disclose that an intermixed layer is produced and the surface oxidized films are mainly composed of titanium oxide with a lesser amount of magnesium oxide. X-ray photoelectron spectroscopy reveals that the oxide has three layers. The outer layer which is 10 nm thick is mainly composed of MgO and TiO{sub 2} with some Mg(OH){sub 2}. The middle layer that is 50 nm thick comprises predominantly TiO{sub 2} and MgO with minor contributions from MgAl{sub 2}O{sub 4} and TiO. The third layer from the surface is rich in metallic Mg, Ti, Al, and Ti{sub 3}Al. The effects of Ti ion implantation on the corrosion resistance and electrochemical behavior of the magnesium alloys are investigated in simulated body fluids at 37{+-}1 deg. C using electrochemical impedance spectroscopy and open circuit potential techniques. Compared to the unimplanted AZ91 alloy, titanium ion implantation significantly shifts the open circuit potential (OCP) to a more positive potential and improves the corrosion resistance at OCP. This phenomenon can be ascribed to the more compact surface oxide film, enhanced reoxidation on the implanted surface, as well as the increased {beta}-Mg{sub 12}Al{sub 17} phase.

  9. Dissipative solitons in pair-ion plasmas

    SciTech Connect

    Ghosh, Samiran; Adak, Ashish Khan, Manoranjan

    2014-01-15

    The effects of ion-neutral collisions on the dynamics of the nonlinear ion acoustic wave in pair-ion plasma are investigated. The standard perturbative approach leads to a Korteweg-de Vries equation with a linear damping term for the dynamics of the finite amplitude wave. The ion-neutral collision induced dissipation is responsible for the linear damping. The analytical solution and numerical simulation reveal that the nonlinear wave propagates in the form of a weakly dissipative compressive solitons. Furthermore, the width of the soliton is proportional to the amplitude of the wave for fixed soliton velocity. Results are discussed in the context of the fullerene pair-ion plasma experiment.

  10. Micro-plasma textured Ti-implant surfaces.

    PubMed

    Beck, U; Lange, R; Neumann, H-G

    2007-02-01

    The surface state of titanium implants modulates bone response and implant anchorage. This evidence brought implant manufacturers to switch from the standard surface refinements and implement new surface treatments for more bone apposition and enhanced interfacial strength measured by removal torque or push-out tests. Anodic plasma-chemical treatment of implant surfaces is a cost-effective process to modify surface topography and chemistry. This technique is used for structuring connected with a coating of implant surfaces. The aim of our investigations, here, is to texture the implant surface in the nanoscale without coating. Ti disks with different mechanical pre-treatment (grinded, glass blasted) were used as substrate. Micro-plasma texturing was carried out in an aqueous electrolyte. By applying a pulsed DC voltage to the specimen, micro-plasma discharge was generated in the thin steam film between immersed specimen and electrolyte. The electrical process parameter current density was varied. The micro-plasma textured Ti surfaces were characterised optically by SEM and electrochemically by CV- (for testing the corrosion parameters), CA- (to give the enlargement of the real surface) and EIS-measurement in range of 100 kHz-100 microHz. We found that the initial structure of the material surface has small or no influence on the results of the micro-plasma treatment. The properties of the thick oxide layer resulting from the plasma process are influenced by electrical process parameters. After removal of the thick oxide layer a fine, micro- and nanoscaled surface structure of the titanium remains.

  11. Ion acceleration by a double stage accelerating device for laser-induced plasma ions

    NASA Astrophysics Data System (ADS)

    Lorusso, A.; Siciliano, M. V.; Velardi, L.; Nassisi, V.

    2010-10-01

    A new laser ion source configuration was studied and realized in order to generate and accelerate ions of different elements. This ion source consisted of a laser-induced plasma from solid targets where the plume was made to expand before the action of the accelerating field. The accelerating field was reached by the application of two high voltage power supplies of different polarity. Therefore, the ions were made to undergo double acceleration that can imprint a maximum ion energy up to 160 keV per charge state. We analyzed the extracted charge from a Cu target as a function of the accelerating voltage at the laser fluences of 1.7 and 2.3 J/cm2. At 60 kV of total accelerating voltage and higher laser fluence, the maximum ion dose was 1012 ions/cm2. Under this last condition, the maximum output current was 5 mA and the emittance measured by the pepper pot method resulted in 0.22π mm mrad. With this machine, biomedical materials such as polyethylene were implanted with carbon and titanium ions. At doses of 6×1015 ions/cm2, the polyethylene surface increased its micro-hardness by about 3-fold, as measured by the scratch test.

  12. Ion acceleration in electrodeless plasma thrusters

    NASA Astrophysics Data System (ADS)

    Lafleur, Trevor; Cannat, Felix; Jarrige, Julien; Elias, Paul-Quentin; Packan, Denis

    2016-09-01

    Since electrodeless plasma thrusters do not use biased electrodes or grids to accelerate ions, it is unclear what determines the magnitude of the ``accelerating voltage'' and hence what the ion beam energy is. In this work a combined theoretical/experimental study of the relationship between the electron temperature and the ion energy was performed to provide such an answer. Experimental measurements show that the ion energy and electron temperature are strongly correlated, and demonstrate that the driving force for the plasma expansion in magnetic nozzles is the electron pressure: in complete analogy to chemical rockets with physical nozzles. Because there are no electrodes or applied voltages, the plasma that exits the thruster must be current-free, and we show that this establishes a strong criterion that determines the maximum accelerating potential that self-forms in the plasma. This maximum accelerating potential (which is between about 4-6 times the electron temperature) is similar to that which develops for a floating sheath, and depends on the electron velocity distribution function. Based on plasma loss considerations inside the thruster cavity, and the drop-off of the ionization cross section for large electron energies in most gases, we predict a theoretical maximum achievable ion beam energy of about 400 eV for argon and xenon propellants.

  13. Method for fabricating MNOS structures utilizing hydrogen ion implantation

    NASA Astrophysics Data System (ADS)

    Saks, N. S.

    1984-05-01

    An improved method for reducing the density of electronic trapping states and fixed insulator charge in the thin oxide layer of an MNOS structure is discussed. The method includes the steps of implanting hydrogen ions in field region of the oxide layer and annealing the MNOS structure at 400 deg C to cause the ions to diffuse laterally into the gate region of the oxide layer.

  14. The Use of Ion Implantation for Materials Processing.

    DTIC Science & Technology

    1980-10-06

    IPreEEhhh I l...fflllffllff NRL Memorandum Report 4341 TheUseofIon Implantation for Materials Processing Semana Progres Report for the Period 1 Oct. 1979...beam current. The temperature was judged by observing of results to be expected from such a Gaussian distribution the color of the samples through a...light multiply tion." ion channeling,’ ’ Coates-Kikuchi lines,’ physical ap- reflected between the front surface and the interface between pearance ( color

  15. Er + medium energy ion implantation into lithium niobate

    NASA Astrophysics Data System (ADS)

    Svecova, B.; Nekvindova, P.; Mackova, A.; Oswald, J.; Vacik, J.; Grötzschel, R.; Spirkova, J.

    2009-05-01

    Erbium-doped lithium niobate (Er:LiNbO3) is a prospective photonics component, operating at 1.5 μm, which could find its use chiefly as an optical amplifier or waveguide laser. In this study, we have focused on the properties of the optically active Er:LiNbO3 layers, which are fabricated by medium energy ion implantation under various experimental conditions. Erbium ions were implanted at energies of 330 and 500 keV with fluences of 1.0 × 1015, 2.5 × 1015 and 1.0 × 1016 cm-2 into LiNbO3 single-crystalline cuts of various orientations. The as-implanted samples were annealed in air at 350 °C for 5 h. The depth distribution and diffusion profiles of the implanted Er were measured by Rutherford Backscattering Spectroscopy (RBS) using 2 MeV He+ ions. The projected range RP and projected range straggling ΔRP were calculated employing the SRIM code. The damage distribution and structural changes were described using the RBS/channelling method. Changes of the lithium concentration depth distribution were studied by Neutron Depth Profiling (NDP). The photoluminescence spectra of the samples were measured to determine whether the emission was in the desired region of 1.5 μm. The obtained data made it possible to reveal the relations between the structural changes of erbium-implanted lithium niobate and its luminescence properties important for photonics applications.

  16. Formation of titanium silicides by high dose ion implantation

    NASA Astrophysics Data System (ADS)

    Salvi, V. P.; Vidwans, S. V.; Rangwala, A. A.; Arora, B. M.; Kuldeep; Jain, Animesh K.

    1987-09-01

    We have investigated titanium silicide formation using high dose (˜ 2 × 10 21 ions/m 2) ion implantation of 30 keV, 48Ti + ions a room temperature into two different types of Si substrates: (a) n-type <111> single crystals and (b) amorphous Si films (˜ 200 nm thick) vacuum deposited onto a thermally grown SiO 2 layer. XRD and RBS techniques were employed to characterize various silicide phases and their depth distribution in as-implanted as well as in annealed samples. We find that a mixture of TiSi, TiSi 2 and Ti 5Si 4 silicides is formed by high dose implantation. Out of these, TiSi; was found to be the dominant phase. The composition of these silicide layers is practically uniform with depth and remains unaltered on heat treatment up to 750° C. The electrical properties of silicide layers have also been investigated using sheet resistance measurements. The resistivity of as-implanted layers is rather high ( ˜ 10 μΩ m), but drops sharply by nearly a factor of 20 after a post-implantation anneal above 800° C. The resistivity of silicide layers thus obtained compare well with silicides prepared by other techniques.

  17. Damage and in-situ annealing during ion implantation

    SciTech Connect

    Sadana, D.K.; Washburn, J.; Byrne, P.F.; Cheung, N.W.

    1982-11-01

    Formation of amorphous (..cap alpha..) layers in Si during ion implantation in the energy range 100 keV-11 MeV and temperature range liquid nitrogen (LN)-100/sup 0/C has been investigated. Cross-sectional transmission electron microscopy (XTEM) shows that buried amorphous layers can be created for both room temperature (RT) and LN temperature implants, with a wider 100 percent amorphous region for the LN cooled case. The relative narrowing of the ..cap alpha.. layer during RT implantation is attributed to in-situ annealing. Implantation to the same fluence at temperatures above 100/sup 0/C does not produce ..cap alpha.. layers. To further investigate in situ annealing effects, specimens already containing buried ..cap alpha.. layers were further irradiated with ion beams in the temperature range RT-400/sup 0/C. It was found that isolated small ..cap alpha.. zones (less than or equal to 50 diameter) embedded in the crystalline matrix near the two ..cap alpha../c interfaces dissolved into the crystal but the thickness of the 100 percent ..cap alpha.. layer was not appreciably affected by further implantation at 200/sup 0/C. A model for in situ annealing during implantation is presented.

  18. Electrostatic ion waves in non-Maxwellian pair-ion plasmas

    SciTech Connect

    Arshad, Kashif; Mahmood, S.

    2010-12-15

    The electrostatic ion waves are studied for non-Maxwellian or Lorentzian distributed unmagnetized pair-ion plasmas. The Vlasov equation is solved and damping rates are calculated for electrostatic waves in Lorentzian pair-ion plasmas. The damping rates of the electrostatic ion waves are studied for the equal and different ion temperatures of pair-ion species. It is found that the Landau damping rate of the ion plasma wave is increased in Lorentzian plasmas in comparison with Maxwellian pair-ion plasmas. The numerical results are also presented for illustration by taking into account the parameters reported in fullerene pair-ion plasma experiments.

  19. Ion implantation in ices of interest for planetology

    NASA Astrophysics Data System (ADS)

    Baratta, G. A.; Fulvio, D.; Garozzo, M.; Gomis, O.; Leto, G.; Palumbo, M. E.; Spinella, F.; Strazzulla, G.

    Frozen sufaces of planetary moons and minor planets in Solar System are continuously irradiated by energetic ions (keV-MeV). These ions deposit their energy into the target via elastic and anelastic collisions which induce a break of molecular bonds. Because of their small penetration depth (0.1 - 2.0 mu m) impinging ions are implanted into the ices at the end of their path. Across the ion's path reconnection of molecular fragments can form new species and if the projectile is a reactive species it can be included into the newly formed molecules. In the Laboratory of Experimental Astrophysics (LASp) of Catania we are investigating the effects of reactive ion implantation in ices of interest for planetology. Results show that some molecules observed on frozen surfaces of minor bodies of the outer Solar System could be formed after implantation of reactive ions. After a short review of relevant experiments performed in our Laboratory we will show results of our latest experiments and their application to the moon of Jupiter Io.

  20. Observations of strong ion-ion correlations in dense plasmas

    SciTech Connect

    Ma, T.; Fletcher, L.; Pak, A.; Chapman, D. A.; Falcone, R. W.; Fortmann, C.; Galtier, E.; Gericke, D. O.; Gregori, G.; Hastings, J.; Landen, O. L.; Le Pape, S.; Lee, H. J.; Nagler, B.; Neumayer, P.; Turnbull, D.; Vorberger, J.; White, T. G.; Wünsch, K.; Zastrau, U.; Glenzer, S. H.; Döppner, T.

    2014-05-01

    Using simultaneous spectrally, angularly, and temporally resolved x-ray scattering, we measure the pronounced ion-ion correlation peak in a strongly coupled plasma. Laser-driven shock-compressed aluminum at ~3× solid density is probed with high-energy photons at 17.9 keV created by molybdenum He-α emission in a laser-driven plasma source. The measured elastic scattering feature shows a well-pronounced correlation peak at a wave vector of k=4k=4Å-1. The magnitude of this correlation peak cannot be described by standard plasma theories employing a linear screened Coulomb potential. Advanced models, including a strong short-range repulsion due to the inner structure of the aluminum ions are however in good agreement with the scattering data. These studies have demonstrated a new highly accurate diagnostic technique to directly measure the state of compression and the ion-ion correlations. We have since applied this new method in single-shot wave-number resolved S(k) measurements to characterize the physical properties of dense plasmas.

  1. Observations of strong ion-ion correlations in dense plasmas

    SciTech Connect

    Ma, T. Pak, A.; Landen, O. L.; Le Pape, S.; Turnbull, D.; Döppner, T.; Fletcher, L.; Galtier, E.; Hastings, J.; Lee, H. J.; Nagler, B.; Glenzer, S. H.; Chapman, D. A.; Falcone, R. W.; Fortmann, C.; Gericke, D. O.; Gregori, G.; White, T. G.; Neumayer, P.; Vorberger, J.; and others

    2014-05-15

    Using simultaneous spectrally, angularly, and temporally resolved x-ray scattering, we measure the pronounced ion-ion correlation peak in a strongly coupled plasma. Laser-driven shock-compressed aluminum at ∼3× solid density is probed with high-energy photons at 17.9 keV created by molybdenum He-α emission in a laser-driven plasma source. The measured elastic scattering feature shows a well-pronounced correlation peak at a wave vector of k=4Å{sup −1}. The magnitude of this correlation peak cannot be described by standard plasma theories employing a linear screened Coulomb potential. Advanced models, including a strong short-range repulsion due to the inner structure of the aluminum ions are however in good agreement with the scattering data. These studies have demonstrated a new highly accurate diagnostic technique to directly measure the state of compression and the ion-ion correlations. We have since applied this new method in single-shot wave-number resolved S(k) measurements to characterize the physical properties of dense plasmas.

  2. 3D concentration distributions of ion implants in amorphous solids

    NASA Astrophysics Data System (ADS)

    Günzler, R.; Weiser, M.; Kalbitz, S.

    1992-01-01

    Spatial distributions of implanted ions have been derived from depth profiles of implants at varied incidence angle by applying tomographic techniques. To this end we have developed a new version of an algorithm known as simultaneous iterative reconstruction technique (SIRT), which covers the experimental concentration range of about three decades. In addition, the finite depth resolution of the nuclear reaction analysis (NRA) is accounted for in our computer program. In this way, we have reconstructed the three-dimensional implantation distributions of 0.15 MeV 1H, 1.5 and 6 MeV 15N, and 4 MeV 30Si in amorphized Ge layers. The agreement with TRIM calculations is reasonable: 10% ± 0.5% for the first and 10% ± 5% for the second range moments. Consequences of the longitudinal and lateral tailing for ion beam applications to large scale integration problems are discussed.

  3. Above room temperature ferromagnetism in Mn-ion implanted Si

    NASA Astrophysics Data System (ADS)

    Bolduc, M.; Awo-Affouda, C.; Stollenwerk, A.; Huang, M. B.; Ramos, F. G.; Agnello, G.; Labella, V. P.

    2005-01-01

    Above room temperature ferromagnetic behavior is achieved in Si through Mn ion implantation. Three-hundred-keV Mn+ ions were implanted to 0.1% and 0.8% peak atomic concentrations, yielding a saturation magnetization of 0.3emu/g at 300K for the highest concentration as measured using a SQUID magnetometer. The saturation magnetization increased by ˜2× after annealing at 800°C for 5min . The Curie temperature for all samples was found to be greater than 400K . A significant difference in the temperature-dependent remnant magnetization between the implanted p-type and n-type Si is observed, giving strong evidence that a Si-based diluted magnetic semiconductor can be achieved.

  4. Hot ion plasma heating experiments in SUMMA

    NASA Technical Reports Server (NTRS)

    Reinmann, J. J.; Lauver, M. R.; Patch, R. W.; Posta, S. J.; Snyder, A.; Englert, G. W.

    1974-01-01

    Initial results are presented for the hot-ion plasma heating experiments conducted in the new SUMMA (superconducting magnetic mirror apparatus) at NASA Lewis Research Center. A discharge is formed by applying a radially inward dc electric field between cylindrical anodes and hallow cathodes located at the peak of the mirrors. Data were obtained at midplane magnetic field strengths from 1.0 to 3.5 tesla. Charge-exchange neutral particle energy analyzer data were reduced to ion temperatures using a plasma model that included a Maxwellian energy distribution superimposed on an azimuthal drift, finite ion orbits, and radial variations in density and electric field. The best ion temperatures in a helium plasma were 5 keV and in hydrogen the H2(+) and H(+) ions were 1.2 keV and 1 keV respectively. Optical spectroscopy line broadening measurements yielded ion temperatures about 50 percent higher than the charge-exchange neutral particle analyzer results. Spectroscopically obtained electron temperature ranged from 3 to 30 eV. Ion temperature was found to scale roughly linearly with the ratio of power input-to-magnetic field strength, P/B.

  5. Zinc ion implantation-deposition technique improves the osteoblast biocompatibility of titanium surfaces

    PubMed Central

    LIANG, YONGQIANG; XU, JUAN; CHEN, JING; QI, MENGCHUN; XIE, XUEHONG; HU, MIN

    2015-01-01

    The plasma immersion ion implantation and deposition (PIIID) technique was used to implant zinc (Zn) ions into smooth surfaces of pure titanium (Ti) disks for investigation of tooth implant surface modification. The aim of the present study was to evaluate the surface structure and chemical composition of a modified Ti surface following Zn ion implantation and deposition and to examine the effect of such modification on osteoblast biocompatibility. Using the PIIID technique, Zn ions were deposited onto the smooth surface of pure Ti disks. The physical structure and chemical composition of the modified surface layers were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), respectively. In vitro culture assays using the MG-63 bone cell line were performed to determine the effects of Zn-modified Ti surfaces following PIIID on cellular function. Acridine orange staining was used to detect cell attachment to the surfaces and cell cycle analysis was performed using flow cytometry. SEM revealed a rough ‘honeycomb’ structure on the Zn-modified Ti surfaces following PIIID processing and XPS data indicated that Zn and oxygen concentrations in the modified Ti surfaces increased with PIIID processing time. SEM also revealed significantly greater MG-63 cell growth on Zn-modified Ti surfaces than on pure Ti surfaces (P<0.05). Flow cytometric analysis revealed increasing percentages of MG-63 cells in S phase with increasing Zn implantation and deposition, suggesting that MG-63 apoptosis was inhibited and MG-63 proliferation was promoted on Zn-PIIID-Ti surfaces. The present results suggest that modification with Zn-PIIID may be used to improve the osteoblast biocompatibility of Ti implant surfaces. PMID:25673139

  6. Extreme Precipitation Strengthening in Ion-Implanted Nickel

    SciTech Connect

    Follstaedt, D.M.; Knapp, J.A.; Myers, S.M.; Petersen, G.A.

    1999-05-03

    Precipitation strengthening of nickel was investigated using ion-implantation alloying and nanoindentation testing for particle separations in the nanometer range and volume fractions extending above 10O/O. Ion implantation of either oxygen alone or oxygen plus aluminum at room temperature was shown to produce substantial strengthening in the ion-treated layer, with yield strengths near 5 GPa in both cases. After annealing to 550"C the oxygen-alone layer loses much of the benefit, with its yield strength reduced to 1.2 GP~ but the dual ion-implanted layer retains a substantially enhanced yield strength of over 4 GPa. Examination by transmission electron f microscopy showed very fine dispersions of 1-5 nm diameter NiO and y-A1203 precipitates in the implanted layers before annealing. The heat treatment at 550"C induced ripening of the NiO particles to sizes ranging from 7 to 20 nm, whereas the more stable ~-A1203 precipitates were little changed. The extreme strengthening we observe is in semiquantitative agreement with predictions based on the application of dispersion-hardening theory to these microstructure.

  7. A New Ion Implant Monitor Electrical Test Structure.

    DTIC Science & Technology

    1986-01-01

    In this paper, a new Ion Implant Monitor test structure and measurement method is reported. A direct measurement of the sheet resistance of the...probe measurements. Voltage measurements are directly converted to sheet resistance , thus measurements may be performed rapidly.

  8. Magnetic and Transport Properties of Mn-ion implanted Si

    NASA Astrophysics Data System (ADS)

    Preisler, V.; Ogawa, M.; Han, X.; Wang, K. L.

    2010-01-01

    We investigate the magnetic and transport properties of Mn-ion implanted Si. Both temperature dependent and field dependent measurements of the samples using a SQUID magnometer reveal ferromagnetic properties at room temperature. Magnetotransport measurements show a large positive magnetoresistance up to 4.5 T with no signs of saturation.

  9. Silicon solar cells by ion implantation and pulsed energy processing

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. R.; Minnucci, J. A.; Shaughnessy, T. S.; Greenwald, A. C.

    1976-01-01

    A new method for fabrication of silicon solar cells is being developed around ion implantation in conjunction with pulsed electron beam techniques to replace conventional furnace processing. Solar cells can be fabricated totally in a vacuum environment at room temperature. Cells with 10% AM0 efficiency have been demonstrated. High efficiency cells and effective automated processing capabilities are anticipated.

  10. Making CoSi(2) Layers By Ion Implantation

    NASA Technical Reports Server (NTRS)

    Namavar, Fereydoon

    1994-01-01

    Monolithic photovoltaic batteries containing vertical cells include buried CoSi(2) contact layers. Vertical-junction photovoltaic cells in series fabricated in monolithic structure. N- and p-doped silicon layers deposited epitaxially. The CoSi(2) layers, formed by ion implantation and annealing, serve as thin, low-resistance ohmic contacts between cells.

  11. Vacancy supersaturations produced by high-energy ion implantation

    SciTech Connect

    Venezia, V.C.; Eaglesham, D.J.; Jacobson, D.C.; Gossmann, H.J.; Haynes, T.E.; Agarwal, A. |; Friessnegg, T.; Nielsen, B.

    1998-01-01

    A new technique for detecting the vacancy clusters produced by high-energy ion implantation into silicon is proposed and tested. This technique takes advantage of the fact that metal impurities, such as Au, are gettered near one-half of the projected range ({1/2}R{sub p}) of MeV implants. The vacancy clustered region produced by a 2 MeV Si{sup +} implant into silicon has been labeled with Au diffused in from the front surface. The trapped Au was detected by Rutherford backscattering spectrometry (RBS) to profile the vacancy clusters. Cross section transmission electron microscopy (XTEM) analysis shows that the Au in the region of vacancy clusters is in the form of precipitates. By annealing MeV implanted samples prior to introduction of the Au, changes in the defect concentration within the vacancy clustered region were monitored as a function of annealing conditions.

  12. Nanocomposite formed by titanium ion implantation into alumina

    SciTech Connect

    Spirin, R. E.; Salvadori, M. C. Teixeira, F. S.; Sgubin, L. G.; Cattani, M.; Brown, I. G.

    2014-11-14

    Composites of titanium nanoparticles in alumina were formed by ion implantation of titanium into alumina, and the surface electrical conductivity measured in situ as the implantation proceeded, thus generating curves of sheet conductivity as a function of dose. The implanted titanium self-conglomerates into nanoparticles, and the spatial dimensions of the buried nanocomposite layer can thus be estimated from the implantation depth profile. Rutherford backscattering spectrometry was performed to measure the implantation depth profile, and was in good agreement with the calculated profile. Transmission electron microscopy of the titanium-implanted alumina was used for direct visualization of the nanoparticles formed. The measured conductivity of the buried layer is explained by percolation theory. We determine that the saturation dose, φ{sub 0}, the maximum implantation dose for which the nanocomposite material still remains a composite, is φ{sub 0} = 2.2 × 10{sup 16 }cm{sup −2}, and the corresponding saturation conductivity is σ{sub 0} = 480 S/m. The percolation dose φ{sub c}, below which the nanocomposite still has basically the conductivity of the alumina matrix, was found to be φ{sub c} = 0.84 × 10{sup 16 }cm{sup −2}. The experimental results are discussed and compared with a percolation theory model.

  13. Ion implantation and annealing studies in III-V nitrides

    SciTech Connect

    Zolper, J.C.; Pearton, S.J.; Williams, J.S.; Tan, H.H.; Karlicek, R.J. Jr.; Stall, R.A.

    1996-12-31

    Ion implantation doping and isolation is expected to play an enabling role for the realization of advanced III-Nitride based devices. In fact, implantation has already been used to demonstrate n- and p-type doping of GaN with Si and Mg or Ca, respectively, as well as to fabricate the first GaN junction field effect transistor. Although these initial implantation studies demonstrated the feasibility of this technique for the III-Nitride materials, further work is needed to realize its full potential. After reviewing some of the initial studies in this field, the authors present new results for improved annealing sequences and defect studies in GaN. First, sputtered AlN is shown by electrical characterization of Schottky and Ohmic contacts to be an effect encapsulant of GaN during the 1,100 C implant activation anneal. The AlN suppresses N-loss from the GaN surface and the formation of a degenerate n{sup +}-surface region that would prohibit Schottky barrier formation after the implant activation anneal. Second, they examine the nature of the defect generation and annealing sequence following implantation using both Rutherford Backscattering (RBS) and Hall characterization. They show that for a Si-dose of 1 x 10{sup 16} cm{sup {minus}2} 50% electrical donor activation is achieved despite a significant amount of residual implantation-induced damage in the material.

  14. Versatile, high-sensitivity faraday cup array for ion implanters

    DOEpatents

    Musket, Ronald G.; Patterson, Robert G.

    2003-01-01

    An improved Faraday cup array for determining the dose of ions delivered to a substrate during ion implantation and for monitoring the uniformity of the dose delivered to the substrate. The improved Faraday cup array incorporates a variable size ion beam aperture by changing only an insertable plate that defines the aperture without changing the position of the Faraday cups which are positioned for the operation of the largest ion beam aperture. The design enables the dose sensitivity range, typically 10.sup.11 -10.sup.18 ions/cm.sup.2 to be extended to below 10.sup.6 ions/cm.sup.2. The insertable plate/aperture arrangement is structurally simple and enables scaling to aperture areas between <1 cm.sup.2 and >750 cm.sup.2, and enables ultra-high vacuum (UHV) applications by incorporation of UHV-compatible materials.

  15. Ion implantation for corrosion inhibition of aluminum alloys in saline media

    SciTech Connect

    Williams, J.M. ); Gonzales, A. ); Quintana, J. ); Lee, I.-S.; Buchanan, R.A. ); Burns, F.C.; Culbertson, R.J.; Levy, M. . Materials Technology Lab.); Treglio, J.R. (ISM

    1990-01-01

    The effects of ion implantation treatments on corrosion of 2014 and 1100 aluminum in saline media were investigated. Implanted ions were N, Si, Ti and Cr. Techniques included salt spray testing, electrochemical studies, Rutherford backscattering spectrometry, and profilometry. It was concluded that ion implantation of Cr is of potential practical benefit for corrosion inhibition of 2014 Al in salt environments. 4 refs., 5 figs.

  16. Ion Implantation Studies of Titanium Metal Surfaces.

    DTIC Science & Technology

    1981-01-01

    Lorenzelli and R. Pascard, Compt. Rend. 259, (1964) 2442-2444. 8. Linus Pauling , The Nature of the Chemical Bond, pg. 92 (Cornell Univ. Press, Ithaca...K. Hirvonen. 3. S. Spooner and K. 0. Legg,lon Implantation Metallurgy, 162 (1980); ed. C. M. Preece and J. K. Hirvonen. 4. L. Pauling , The Nature of...R from the Pauling electronegativity scale. According to Pauling (8), the contribu- tion of the bond to the heat of formation is Q - 23 (YEr - Yc) 2

  17. Ultrahigh-current-density metal-ion implantation and diamondlike-hydrocarbon films for tribological applications; Final report

    SciTech Connect

    Wilbur, P.J.

    1993-09-01

    The metal-ion-implantation system used to implant metals into substrates are described. The metal vapor required for operation is supplied by drawing sufficient electron current from the plasma discharge to an anode-potential crucible so a solid, pure metal placed in the crucible will be heated to the point of vaporization. The ion-producing, plasma discharge is initiated within a graphite-ion-source body, which operates at high temperature, by using an argon flow that is turned off once the metal vapor is present. Extraction of ion beams several cm in diameter at current densities ranging to several hundred {mu}A/cm{sup 2} on a target 50 cm downstream of the ion source have been demonstrated using Mg, Ag, Cr, Cu, Si, Ti, V, B and Zr. These metals were implanted into over 100 substrates (discs, pins, flats, wires). A model describing thermal stresses induced in materials (e.g. ceramic plates) during high-current-density implantation is presented. Tribological and microstructural characteristics of iron and 304-stainless-steel samples implanted with Ti or B are examined. Diamondlike-hydrocarbon coatings were applied to steel surfaces and found to exhibit good tribological performance.

  18. Ion Channeling Analysis of Gallium Nitride Implanted with Deuterium

    SciTech Connect

    Myers, S.M.; Wampler, W.R.

    1998-12-23

    Ion channeling and transmission electron microscopy were used to examine the microstructure of GaN implanted with deuterium (D) at high (>1 at. %) and low (< 0.1 at. %) D concentrations. At high concentrations, bubbles and basal-plane stacking faults were observed. Ion channeling showed the D was disordered relative to the GaN lattice, consistent with precipitation of D2 into bubbles. At low D concentrations, bubbles and stacking faults are absent and ion channeling shows that a large fraction of the D occupies sites near the center of the c-axis channel.

  19. Zinc-ion implanted and deposited titanium surfaces reduce adhesion of Streptococccus mutans

    NASA Astrophysics Data System (ADS)

    Xu, Juan; Ding, Gang; Li, Jinlu; Yang, Shenhui; Fang, Bisong; Sun, Hongchen; Zhou, Yanmin

    2010-10-01

    While titanium (Ti) is a commonly used dental implant material with advantageous biocompatible and mechanical properties, native Ti surfaces do not have the ability to prevent bacterial colonization. The objective of this study was to evaluate the chemical composition and bacterial adhesive properties of zinc (Zn) ion implanted and deposited Ti surfaces (Zn-PIIID-Ti) as potential dental implant materials. Surfaces of pure Ti (cp-Ti) were modified with increasing concentrations of Zn using plasma immersion ion implantation and deposition (PIIID), and elemental surface compositions were characterized by X-ray photoelectron spectrometry (XPS). To evaluate bacterial responses, Streptococcus mutans were seeded onto the modifiedTi surfaces for 48 h and subsequently observed by scanning electron microscopy. Relative numbers of bacteria on each surface were assessed by collecting the adhered bacteria, reculturing and counting colony forming units after 48 h on bacterial grade plates. Ti, oxygen and carbon elements were detected on all surfaces by XPS. Increased Zn signals were detected on Zn-PIIID-Ti surfaces, correlating with an increase of Zn-deposition time. Substantial numbers of S. mutans adhered to cp-Ti samples, whereas bacterial adhesion on Zn-PIIID-Ti surfaces signficantly decreased as the Zn concentration increased ( p < 0.01). In conclusion, PIIID can successfully introduce Zn onto a Ti surface, forming a modified surface layer bearing Zn ions that consequently deter adhesion of S. mutans, a common bacterium in the oral environment.

  20. Application of Coaxial Ion Gun for Film Generation and Ion Implantation

    NASA Astrophysics Data System (ADS)

    Takatsu, Mikio; Asai, Tomohiko; Kurumi, Satoshi; Suzuki, Kaoru; Hirose, Hideharu; Masutani, Shigeyuki

    A magnetized coaxial plasma gun (MCPG) is here utilized for deposition on high-melting-point metals. MCPGs have hitherto been studied mostly in the context of nuclear fusion research, for particle and magnetic helicity injection and spheromak formation. During spheromak formation, the electrode materials are ionized and mixed into the plasmoid. In this study, this ablation process by gun-current sputtering is enhanced for metallic thin-film generation. In the proposed system geometry, only ionized materials are electromagnetically accelerated by the self-Lorentz force, with ionized operating gas as a magnetized thermal plasmoid, contributing to the thin-film deposition. This reduces the impurity and non-uniformity of the deposited thin-film. Furthermore, as the ions are accelerated in a parallel direction to the injection axis, vertical implantation of the ions into the substrate surface is achieved. To test a potential application of the developed system, experiments were conducted involving the formation of a buffer layer on hard ceramics, for use in dental materials.

  1. Broad-beam, high current, metal ion implantation facility

    SciTech Connect

    Brown, I.G.; Dickinson, M.R.; Galvin, J.E.; Godechot, X.; MacGill, R.A.

    1990-07-01

    We have developed a high current metal ion implantation facility with which high current beams of virtually all the solid metals of the Periodic Table can be produced. The facility makes use of a metal vapor vacuum arc ion source which is operated in a pulsed mode, with pulse width 0.25 ms and repetition rate up to 100 pps. Beam extraction voltage is up to 100 kV, corresponding to an ion energy of up to several hundred keV because of the ion charge state multiplicity; beam current is up to several Amperes peak and around 10 mA time averaged delivered onto target. Implantation is done in a broad-beam mode, with a direct line-of-sight from ion source to target. Here we describe the facility and some of the implants that have been carried out using it, including the seeding' of silicon wafers prior to CVD with titanium, palladium or tungsten, the formation of buried iridium silicide layers, and actinide (uranium and thorium) doping of III-V compounds. 16 refs., 6 figs.

  2. Beam-plasma interactions in a positive ion-negative ion plasma

    NASA Technical Reports Server (NTRS)

    Intrator, T.; Hershkowitz, N.; Stern, R.

    1983-01-01

    An electron-free plasma consisting of negative ions /SF6(-)/ and positive ions /Ar(+)/, and negligible neutral-ion collision frequencies has been created in the laboratory. This plasma has a mass ratio of approximately 3.5-similar to many computer particle-in-cell simulated systems. A fluid description of this positive and negative ion confinement (PANIC) plasma is given and compared to experimental measurements of a beam-plasma instability for both beam species and a wide range of beam energies. The fluid dispersion relation and most growing modes are predicted to be insensitive to many parameters of the PANIC beam-plasma system, and found to the consistent with the data.

  3. High Frequency Plasma Generators for Ion Thrusters

    NASA Technical Reports Server (NTRS)

    Divergilio, W. F.; Goede, H.; Fosnight, V. V.

    1981-01-01

    The results of a one year program to experimentally adapt two new types of high frequency plasma generators to Argon ion thrusters and to analytically study a third high frequency source concept are presented. Conventional 30 cm two grid ion extraction was utilized or proposed for all three sources. The two plasma generating methods selected for experimental study were a radio frequency induction (RFI) source, operating at about 1 MHz, and an electron cyclotron heated (ECH) plasma source operating at about 5 GHz. Both sources utilize multi-linecusp permanent magnet configurations for plasma confinement. The plasma characteristics, plasma loading of the rf antenna, and the rf frequency dependence of source efficiency and antenna circuit efficiency are described for the RFI Multi-cusp source. In a series of tests of this source at Lewis Research Center, minimum discharge losses of 220+/-10 eV/ion were obtained with propellant utilization of .45 at a beam current of 3 amperes. Possible improvement modifications are discussed.

  4. Ion-implanted laser annealed silicon solar cells

    NASA Technical Reports Server (NTRS)

    Katzeff, J. S.

    1980-01-01

    Development of low cost solar cells fabrication technology is being sponsored by NASA JPL as part of the Low Cost Solar Array Project (LSA). In conformance to Project requirements ion implantation and laser annealing were evaluated as junction formation techniques offering low cost-high throughput potential. Properties of cells fabricated utilizing this technology were analyzed by electrical, transmission electron microscopy, Rutherford backscattering and secondary ion mass spectrometry techniques. Tests indicated the laser annealed substrates to be damage free and electrically active. Similar analysis of ion implanted furnace annealed substrates revealed the presence of residual defects in the form of dislocation lines and loops with substantial impurity redistribution evident for some anneal temperature/time regimes. Fabricated laser annealed cells exhibited improved spectral response and conversion efficiency in comparison to furnace annealed cells. An economic projection for LSA indicates a potential for considerable savings from laser annealing technology.

  5. The effect of plasma-sprayed coatings on the fatigue of titanium alloy implants

    NASA Astrophysics Data System (ADS)

    Smith, Todd

    1994-02-01

    The application of titanium plasma-spray coatings to Ti-6Al-4V orthopedic implants results in a dramatic decrease in high-cycle fatigue performance. The better bonding of the plasma sprayed and heat-treated implants results in a lower high-cycle fatigue strength. Therefore, the use of plasma-spray textured coatings on implants must be considered with caution.

  6. Sources for Low Energy Extreme of Ion Implantation

    SciTech Connect

    Hershcovitch, A.; Johnson, B. M.; Batalin, V. A.; Kolomiets, A. A.; Kropachev, G. N.; Kuibeda, R. P.; Kulevoy, T. V.; Pershin, V. I.; Petrenko, S. V.; Rudskoy, I.; Seleznev, D. N.; Bugaev, A. S.; Gushenets, V. I.; Oks, E. M.; Yushkov, G. Yu.; Masunov, E. S.; Polozov, S. M.; Poole, H. J.; Storozhenko, P. A.; Svarovski, A. Ya.

    2008-11-03

    A joint research and development effort focusing on the design of steady state, intense ion sources has been in progress for the past four and a half years. The ultimate goal is to meet the two, energy extreme range needs of mega-electron-volt and 100's of electron-volt ion implanters. This endeavor has resulted in record steady state output currents of higher charge state Antimony and Phosphorous ions: P{sup 2+}(8.6 pmA), P{sup 3+}(1.9 pmA), and P{sup 4+}(0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb{sup 3+} Sb{sup 4+}, Sb{sup 5+}, and Sb{sup 6+} respectively. During the past year the effort was channeled towards low energy implantation, for which the effort involved molecular ions and a novel plasmaless/gasless deceleration method. To date, 3 emA of positive Decaborane ions were extracted at 14 keV and a smaller current of negative Decaborane ions were also extracted. Additionally, a Boron fraction of over 70% was extracted from a Bernas-Calutron ion source.

  7. Characterization of carbon ion implantation induced graded microstructure and phase transformation in stainless steel

    SciTech Connect

    Feng, Kai; Wang, Yibo; Li, Zhuguo; Chu, Paul K.

    2015-08-15

    Austenitic stainless steel 316L is ion implanted by carbon with implantation fluences of 1.2 × 10{sup 17} ions-cm{sup −} {sup 2}, 2.4 × 10{sup 17} ions-cm{sup −} {sup 2}, and 4.8 × 10{sup 17} ions-cm{sup −} {sup 2}. The ion implantation induced graded microstructure and phase transformation in stainless steel is investigated by X-ray diffraction, X-ray photoelectron spectroscopy and high resolution transmission electron microscopy. The corrosion resistance is evaluated by potentiodynamic test. It is found that the initial phase is austenite with a small amount of ferrite. After low fluence carbon ion implantation, an amorphous layer and ferrite phase enriched region underneath are formed. Nanophase particles precipitate from the amorphous layer due to energy minimization and irradiation at larger ion implantation fluence. The morphology of the precipitated nanophase particles changes from circular to dumbbell-like with increasing implantation fluence. The corrosion resistance of stainless steel is enhanced by the formation of amorphous layer and graphitic solid state carbon after carbon ion implantation. - Highlights: • Carbon implantation leads to phase transformation from austenite to ferrite. • The passive film on SS316L becomes thinner after carbon ion implantation. • An amorphous layer is formed by carbon ion implantation. • Nanophase precipitate from amorphous layer at higher ion implantation fluence. • Corrosion resistance of SS316L is improved by carbon implantation.

  8. Miniaturized EAPs with compliant electrodes fabricated by ion implantation

    NASA Astrophysics Data System (ADS)

    Shea, H.

    2011-04-01

    Miniaturizing dielectric electroactive polymer (EAP) actuators will lead to highly-integrated mechanical systems on a chip, combining dozens to thousands of actuators and sensors on a few cm2. We present here µm to mm scale electroactive polymer (EAP) devices, batch fabricated on the chip or wafer scale, based on ion-implanted electrodes. Low-energy (2-10 keV) implantation of gold ions into a silicone elastomer leads to compliant stretchable electrodes consisting of a buried 20 nm thick layer of gold nanoparticles in a silicone matrix. These electrodes: 1) conduct at strains up to 175%, 2) are patternable on the µm scale, 3) have stiffness similar to silicone, 4) have good conductivity, and 5) excellent adhesion since implanted in the silicone. The EAP devices consist of 20 to 30 µm thick silicone membranes with µm to mm-scale ion-implanted electrodes on both sides, bonded to a holder. Depending on electrode shape and membrane size, several actuation modes are possible. Characterization of 3mm diameter bi-directional buckling mode actuators, mm-scale tunable lens arrays, 2-axis beam steering mirrors, as well as arrays of 72 cell-size (100x200 µm2) actuators to apply mechanical strain to single cells are reported. Speeds of up to several kHz are observed.

  9. Ion Kinetics in Silane Plasmas

    DTIC Science & Technology

    1988-04-20

    reactivity but by the electrical properties of the plasma. Current continuity, impedance matching, and the cou- pling between total charged particle fluxes...theory. Since the chemical and physical properties of the noble-gases vary monotonically down the periods of Mendeleev’s table, one might anticipate a...chemistry in its title is concerned only with the properties and reactions of positively charged species. Anions play a qualitatively different and important

  10. Plasma Studies in Ion Diodes.

    DTIC Science & Technology

    1984-09-01

    high power pulse, with a typical rise time of 10 ns, to a pulsed high current vacuum diode (also variously referred to as an explosive emission , field...instantaneous event. One motivation for such studies was the developement of high voltage devices, such as x - ray tubes. for which vacuum breakdown was...Sources of high current , high voltage particle beams rely on the intermedi- ate phase of vacuum breakdown, between initial plasma formation and gap clo

  11. Industrial hygiene and control technology assessment of ion implantation operations.

    PubMed

    Ungers, L J; Jones, J H

    1986-10-01

    Ion implantation is a process used to create the functional units (pn junctions) of integrated circuits, photovoltaic (solar) cells and other semiconductor devices. During the process, ions of an impurity or a "dopant" material are created, accelerated and imbedded in wafers of silicon. Workers responsible for implantation equipment are believed to be at risk from exposure to both chemical (dopant compounds) and physical (ionizing radiation) agents. In an effort to characterize the chemical exposures, monitoring for chemical hazards was conducted near eleven ion implanters at three integrated circuit facilities, while ionizing radiation was monitored near four of these units at two of the facilities. The workplace monitoring suggests that ion implantation operators routinely are exposed to low-level concentrations of dopants. Although the exact nature of dopant compounds released to the work environment was not determined, area and personal samples taken during normal operating activities found concentrations of arsenic, boron and phosphorous below OSHA Permissible Exposure Limits (PELs) for related compounds; area samples collected during implanter maintenance activities suggest that a potential exists for more serious exposures. The results of badge dosimetry monitoring for ionizing radiation indicate that serious exposures are unlikely to occur while engineering controls remain intact. All emissions were detected at levels unlikely to result in exposures above the OSHA standard for the whole body (1.25 rems per calendar quarter). The success of existing controls in preventing worker exposures is discussed. Particular emphasis is given to the differential exposures likely to be experienced by operators and maintenance personnel.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Multi-Zone Modeling of Ion-Implanted Impurity Redistribution.

    NASA Astrophysics Data System (ADS)

    Araujo, Carlos Alberto Paz De.

    Implanted impurity redistribution has been observed during the annealing step of many ion-implanted materials. Throughout the ion-implantation literature, experimental evidence suggests some position dependence in the redistribution process. Specifically, the tail region of ion-implanted impurity profiles usually exhibit fast diffusion during annealing whereas the near-surface region shows slow diffusion. To date, redistribution models have failed to include this spacial dependence in the diffusion coefficient of ion -implanted impurities. Analytical expressions for the post -annealing profile are usually found from oversimplified redistribution models that employ Fick's second law with a reflecting surface boundary condition and a homogeneous semi-infinite medium. This modeling scheme is not capable to accommodate regions of high or low redistribution because of the restriction of a single diffusion constant. In general the ideal gaussian LSS profile is assumed as the initial condition rendering an analytic solution to the simple diffusion model that is capable of modeling only gaussian broadening. The approach taken in the present work is to model the ion-implanted substrate as a stratified medium with zones where a local diffusion equation is obeyed. An effective diffusion coefficient is defined within each zone with the intent to lump local disturbances such as defects and precipitates. Thus, regions of low or high redistribution are modeled by zones of large or small effective diffusion coefficients. Because it is not always possible to have an analytical expression for the pre-annealing profile the multi-zone modeling scheme developed in this work accepts any type of initial condition. In order to accomplish this level of generality the Crank-Nicolson numerical formula is used to solve the multi-zone equations. Also, the Crout-Doolittle matrix reduction algorithm is utilized to reduce the computation time. The multi-zone modeling scheme is tested for the case

  13. Characterization of Ion-Implanted Semiconductors

    DTIC Science & Technology

    1980-11-01

    UM OFNovoE •-_• Air Force Wright Aeronautical Laboratories (A C 3.NUMBER OF, WAGES ’ Wright-Pattexson AFB. Ohio 4%433 241 14. 14ON’|T/QRNG-AGENCY..NAME...monotonical) v with ion dose at all anneal temperatures before the conversion to n-type occurs , :od a moi!bilitv minimuns is evident at a dose of 3 lýl1 CM

  14. Laser Annealing of Ion Implanted Silicon.

    DTIC Science & Technology

    1981-08-01

    Lett. 35, 608 (1979). 6. B. L. Crowder, R. S. Title, M. H. Brodsky, and G. D. Petit, Appl. Phys. Lett. 16, 205 (1970). - 7. J. A. Van Vechten, R. Tsu ...LASER ANNEALING OF ION IMPLANTEDSILICON(U) ILLINOIS 2/2 UNIV AT URBANA C ORDI ATED SCIENCE LAO A SHATTACHARYYAI A iR9i 964-MCS2 UNCLASSIFIED RG1R-1

  15. Charge neutralization apparatus for ion implantation system

    DOEpatents

    Leung, Ka-Ngo; Kunkel, Wulf B.; Williams, Malcom D.; McKenna, Charles M.

    1992-01-01

    Methods and apparatus for neutralization of a workpiece such as a semiconductor wafer in a system wherein a beam of positive ions is applied to the workpiece. The apparatus includes an electron source for generating an electron beam and a magnetic assembly for generating a magnetic field for guiding the electron beam to the workpiece. The electron beam path preferably includes a first section between the electron source and the ion beam and a second section which is coincident with the ion beam. The magnetic assembly generates an axial component of magnetic field along the electron beam path. The magnetic assembly also generates a transverse component of the magnetic field in an elbow region between the first and second sections of the electron beam path. The electron source preferably includes a large area lanthanum hexaboride cathode and an extraction grid positioned in close proximity to the cathode. The apparatus provides a high current, low energy electron beam for neutralizing charge buildup on the workpiece.

  16. Dependence of implantation sequence on surface blistering characteristics due to H and He ions co-implanted in silicon

    NASA Astrophysics Data System (ADS)

    Liang, J. H.; Hsieh, H. Y.; Wu, C. W.; Lin, C. M.

    2015-12-01

    This study investigated surface blistering characteristics due to H and He ions co-implanted in silicon at room temperature. The H and He ion energies were 40 and 50 keV, respectively, so that their depth profiles were similar. The total implantation fluence for the H and He ions was 5 × 1016 cm-2 under various fluence fractions in the H ions. The implantation sequences under investigation were He + H and H + He. Dynamic optical microscopy (DOM) was employed in order to dynamically analyze surface blistering characteristics. This study used DOM data to construct so-called time-temperature-transformation (T-T-T) curves to easily predict blistering and crater transformation at specific annealing times and temperatures. The results revealed that the curves of blister initialization, crater initialization, and crater completion in the He + H implant occurred at a lower annealing temperature but with a longer annealing time compared to those in the H + He implant. Furthermore, the threshold annealing temperatures for blister and crater formation in the He + H implant were lower than they were in the H + He implant. The size distributions of the blisters and craters in the He + H implant extended wider than those in the H + He implant. In addition, the He + H implant exhibited larger blisters and craters compared to the ones in the H + He implant. Since the former has a higher percentage of exfoliation area than the latter, it is regarded as the more optimal implantation sequence.

  17. Fabrication of poly(vinyl carbazole) waveguides by oxygen ion implantation

    NASA Astrophysics Data System (ADS)

    Ghailane, Fatima; Manivannan, Gurusamy; Knystautas, Émile J.; Lessard, Roger A.

    1995-08-01

    Polymer waveguides were fabricated by ion implantation involving poly(vinyl carbazole) films. This material was implanted by oxygen ions (O ++ ) of energies ranging from 50 to 250 keV. The ion doses varied from 1010 to 1015 ions / cm2. The conventional prism-film coupler method was used to determine the waveguiding nature of the implanted and unimplanted films. The increase of the surface refractive index in the implanted layer has been studied by measuring the effective refractive index (neff) for different optical modes. Electron spectroscopy chemical analysis measurements were also performed to assess the effect of ion implantation on the polymer matrix.

  18. Fast ion beam-plasma interaction system.

    PubMed

    Breun, R A; Ferron, J R

    1979-07-01

    A device has been constructed for the study of the interaction between a fast ion beam and a target plasma of separately controllable parameters. The beam of either hydrogen or helium ions has an energy of 1-4 keV and a total current of 0.5-2 A. The beam energy and beam current can be varied separately. The ion source plasma is created by a pulsed (0.2-10-ms pulse length) discharge in neutral gas at up to 3 x 10(-3) Torr. The neutrals are pulsed into the source chamber, allowing the neutral pressure in the target region to remain less than 5 x 10(-5) Torr at a 2-Hz repetition rate. The creation of the source plasma can be described by a simple set of equations which predict optimum source design parameters. The target plasma is also produced by a pulsed discharge. Between the target and source chambers the beam is neutralized by electrons drawn from a set of hot filaments. Currently under study is an unstable wave in a field-free plasma excited when the beam velocity is nearly equal to the target electron thermal velocity (v(beam) approximately 3.5 x 10(7) cm/s, Te = 0.5 eV).

  19. Ion beam control in laser plasma interaction

    NASA Astrophysics Data System (ADS)

    Kawata, S.; Izumiyama, T.; Sato, D.; Nagashima, T.; Takano, M.; Barada, D.; Gu, Y. J.; Ma, Y. Y.; Kong, Q.; Wang, P. X.; Wang, W. M.

    2016-03-01

    By a two-stage successive acceleration in laser ion acceleration, our 2.5-dimensional particle-in-cell simulations demonstrate a remarkable increase in ion energy by a few hundreds of MeV; the maximum proton energy reaches about 250MeV. The ions are accelerated by the inductive continuous post-acceleration in a laser plasma interaction together with the target normal sheath acceleration and the breakout afterburner mechanism. An intense short-pulse laser generates a strong current by high-energy electrons accelerated, when an intense short- pulse laser illuminates a plasma target. The strong electric current creates a strong magnetic field along the high-energy electron current in the plasma. During the increase phase in the magnetic field strength, the moving longitudinal inductive electric field is induced by the Faraday law, and accelerates the forward-moving ions continously. The multi-stage acceleration provides a unique controllability in the ion energy and its quality.

  20. Ion Acceleration in Plasmas with Alfven Waves

    SciTech Connect

    O.Ya. Kolesnychenko; V.V. Lutsenko; R.B. White

    2005-06-15

    Effects of elliptically polarized Alfven waves on thermal ions are investigated. Both regular oscillations and stochastic motion of the particles are observed. It is found that during regular oscillations the energy of the thermal ions can reach magnitudes well exceeding the plasma temperature, the effect being largest in low-beta plasmas (beta is the ratio of the plasma pressure to the magnetic field pressure). Conditions of a low stochasticity threshold are obtained. It is shown that stochasticity can arise even for waves propagating along the magnetic field provided that the frequency spectrum is non-monochromatic. The analysis carried out is based on equations derived by using a Lagrangian formalism. A code solving these equations is developed. Steady-state perturbations and perturbations with the amplitude slowly varying in time are considered.

  1. Xenon diffusion following ion implantation into feldspar - Dependence on implantation dose

    NASA Technical Reports Server (NTRS)

    Melcher, C. L.; Burnett, D. S.; Tombrello, T. A.

    1982-01-01

    The diffusion properties of xenon implanted into feldspar, a major mineral in meteorites and lunar samples, are investigated in light of the importance of xenon diffusion in the interpretation of early solar system chronologies and the retention time of solar-wind-implanted Xe. Known doses of Xe ions were implanted at an energy of 200 keV into single-crystal plagioclase targets, and depth profiles were measured by alpha particle backscattering before and after annealing for one hour at 900 or 1000 C. The fraction of Xe retained following annealing is found to be strongly dependent on implantation dose, being greatest at a dose of 3 x 10 to the 15th ions/sq cm and decreasing at higher and lower doses. Xe retention is also observed to be unaffected by two-step anneals, or by implantation with He or Ar. Three models of the dose-dependent diffusion properties are considered, including epitaxial crystal regrowth during annealing controlled by the extent of radiation damage, the creation of trapping sites by radiation damage, and the inhibition of recrystallization by Xe during annealing

  2. Ion Implantation of Wide Bandgap Semiconductors.

    DTIC Science & Technology

    1978-05-01

    u s i n g nomina l l v • S’~ xi lane in UHP argon and r o u g h ly eq u i va l e n t system cond it ions. We probably obtained a h o t t i t ’ of...dilute silane that is more c o nce n t rat e d han t he nomina l 1 .5Z reques ted . Both Auger ana l vs is and Rut her f o rd b ackscu t t er ing

  3. Fabrication of Graphene Using Carbon Ion Implantation

    NASA Astrophysics Data System (ADS)

    Colon, Tomeka; Smith, Cydale; Muntele, Claudiu

    2012-02-01

    Graphene is a flat monolayer of carbon atoms tightly packed into a two-dimensional (2D) honeycomb lattice and is a basic building block for graphitic materials of all other dimensionalities. It can be wrapped up into 0D fullerenes, rolled into 1D nanotubes, or stacked into 3D graphite. Graphene's high electrical conductivity and high optical transparency make it a candidate for transparent conducting electrodes, required for such applications as touchscreens, liquid crystal displays, organic photovoltaic cells, and organic light-emitting diodes. In particular, graphene's mechanical strength and flexibility are advantageous compared to indium tin oxide, which is brittle, and graphene films may be deposited from solution over large areas. One method to grow epitaxial graphene is by starting with single crystal silicon carbide (SiC). When SiC is heated under certain conditions, silicon evaporates leaving behind carbon that reorganizes into layers of graphene. Here we report on an alternate method of producing graphene by using low energy carbon implantation in a nickel layer deposited on silicon dioxide mechanical support, followed by heat treatment in a reducing atmosphere to induce carbon migration and self-assembly. We used high resolution RBS and Raman spectroscopy for process and sample characterization. Details will be discussed during the meeting.

  4. High yield antibiotic producing mutants of Streptomyces erythreus induced by low energy ion implantation

    NASA Astrophysics Data System (ADS)

    Yu, Chen; Zhixin, Lin; Zuyao, Zou; Feng, Zhang; Duo, Liu; Xianghuai, Liu; Jianzhong, Tang; Weimin, Zhu; Bo, Huang

    1998-05-01

    Conidia of Streptomyces erythreus, an industrial microbe, were implanted by nitrogen ions with energy of 40-60 keV and fluence from 1 × 10 11 to 5 × 10 14 ions/cm 2. The logarithm value of survival fraction had good linear relationship with the logarithm value of fluence. Some mutants with a high yield of erythromycin were induced by ion implantation. The yield increment was correlated with the implantation fluence. Compared with the mutation results induced by ultraviolet rays, mutation effects of ion implantation were obvious having higher increasing erythromycin potency and wider mutation spectrum. The spores of Bacillus subtilis were implanted by arsenic ions with energy of 100 keV. The distribution of implanted ions was measured by Rutherford Backscattering Spectrometry (RBS) and calculated in theory. The mechanism of mutation induced by ion implantation was discussed.

  5. Develop techniques for ion implantation of PLZT for adaptive optics

    NASA Astrophysics Data System (ADS)

    Craig, R. A.; Batishko, C. R.; Brimhall, J. L.; Pawlewicz, W. T.; Stahl, K. A.

    1989-11-01

    Battelle Pacific Northwest Laboratory (PNL) conducted research into the preparation and characterization of ion-implanted adaptive optic elements based on lead-lanthanum-zirconate-titanate (PLZT). Over the 4-yr effort beginning FY 1985, the ability to increase the photosensitivity of PLZT and extend it to longer wavelengths was developed. The emphasis during the last two years was to develop a model to provide a basis for choosing implantation species and parameters. Experiments which probe the electronic structure were performed on virgin and implanted PLZT samples. Also performed were experiments designed to connect the developing conceptual model with the experimental results. The emphasis in FY 1988 was to extend the photosensitivity out to diode laser wavelengths. The experiments and modelling effort indicate that manganese will form appropriate intermediate energy states to achieve the longer wavelength photosensitivity. Preliminary experiments were also conducted to deposit thin film PLZT.

  6. Ion Implantation Metallurgy: A Study of the Composition, Structure and Corrosion Behavior of Surface Alloys Formed by Ion Implantation.

    DTIC Science & Technology

    1980-04-01

    Composition of 304 Stainless Steel %Cr ’Y Ni % Mn % Si % Mo % C % N % S % P 18.18 8.48 1.75 0.5 0.36 0.051 0.05 0.005 0.028 Coupons of 7x7xl mm were cut from...anodic- ally dissolved metal and subsequent incorporation into the passive film via a bridging bond with the bound water at the nearby passive film...IMPLANTATION - INDUCED AMORPHICITY IN GOLD Ion implantation has been shown to produce highly metastable phases similar to those formed by ultra-rapid

  7. Ions beams and ferroelectric plasma sources

    NASA Astrophysics Data System (ADS)

    Stepanov, Anton

    Near-perfect space-charge neutralization is required for the transverse compression of high perveance ion beams for ion-beam-driven warm dense matter experiments, such as the Neutralized Drift Compression eXperiment (NDCX). Neutralization can be accomplished by introducing a plasma in the beam path, which provides free electrons that compensate the positive space charge of the ion beam. In this thesis, charge neutralization of a 40 keV, perveance-dominated Ar+ beam by a Ferroelectric Plasma Source (FEPS) is investigated. First, the parameters of the ion beam, such as divergence due to the extraction optics, charge neutralization fraction, and emittance were measured. The ion beam was propagated through the FEPS plasma, and the effects of charge neutralization were inferred from time-resolved measurements of the transverse beam profile. In addition, the dependence of FEPS plasma parameters on the configuration of the driving pulser circuit was studied to optimize pulser design. An ion accelerator was constructed that produced a 30-50 keV Ar + beam with pulse duration <300 mus and dimensionless perveance Q up to 8 x 10-4. Transverse profile measurements 33 cm downstream of the ion source showed that the dependence of beam radius on Q was consistent with space charge expansion. It was concluded that the beam was perveance-dominated with a charge neutralization fraction of approximately zero in the absence of neutralizing plasma. Since beam expansion occurred primarily due to space charge, the decrease in effective perveance due to neutralization by FEPS plasma can be inferred from the reduction in beam radius. Results on propagation of the ion beam through FEPS plasma demonstrate that after the FEPS is triggered, the beam radius decreases to its neutralized value in about 5 mus. The duration of neutralization was about 10 mus at a charging voltage VFEPS = 5.5 kV and 35 mus at VFEPS = 6.5 kV. With VFEPS = 6.5 kV, the transverse current density profile 33 cm downstream

  8. Electron-less negative ion extraction from ion-ion plasmas

    SciTech Connect

    Rafalskyi, Dmytro; Aanesland, Ane

    2015-03-09

    This paper presents experimental results showing that continuous negative ion extraction, without co-extracted electrons, is possible from highly electronegative SF{sub 6} ion-ion plasma at low gas pressure (1 mTorr). The ratio between the negative ion and electron densities is more than 3000 in the vicinity of the two-grid extraction and acceleration system. The measurements are conducted by both magnetized and non-magnetized energy analyzers attached to the external grid. With these two analyzers, we show that the extracted negative ion flux is almost electron-free and has the same magnitude as the positive ion flux extracted and accelerated when the grids are biased oppositely. The results presented here can be used for validation of numerical and analytical models of ion extraction from ion-ion plasma.

  9. Energy loss of ions implanted in MOS dielectric films

    NASA Astrophysics Data System (ADS)

    Shyam, Radhey

    Energy loss measurements of ions in the low kinetic energy regime have been made on as-grown SiO2(170-190nm) targets. Singly charged Na + ions with kinetic energies of 2-5 keV and highly charged ions Ar +Q (Q=4, 8 and 11) with a kinetic energy of 1 keV were used. Excitations produced by the ion energy loss in the oxides were captured by encapsulating the irradiated oxide under a top metallic contact. The resulting Metal-Oxide-Semiconductor (MOS) devices were probed with Capacitance-Voltage (C V) measurements and extracted the flatband voltages from the C-V curves. The C-V results for singly charged ion experiments reveal that the changes in the flatband voltage and slope for implanted devices relative to the pristine devices can be used to delineate effects due to implanted ions only and ion induced damage. The data shows that the flatband voltage shifts and C-V slope changes are energy dependent. The observed changes in flatband voltage which are greater than those predicted by calculations scaled for the ion dose and implantation range (SRIM). These results, however, are consistent with a columnar recombination model, where electron-hole pairs are created due to the energy deposited by the implanted ions within the oxide. The remaining holes left after recombination losses are diffused through the oxide at the room temperature and remain present as trapped charges. Comparison of the data with the total number of the holes generated gives a fractional yield of 0.0124 which is of the same order as prior published high energy irradiation experiments. Additionally, the interface trap density, extracted from high and low frequency C-V measurements is observed to increase by one order of magnitude over our incident beam energy. These results confirm that dose- and kinetic energy -dependent effects can be recorded for singly charged ion irradiation on oxides using this method. Highly charged ion results also confirm that dose as well as and charge-dependent effects can

  10. Gyrophase bunched ions in the plasma sheet

    NASA Astrophysics Data System (ADS)

    Wang, Zhiqiang; Zhai, Hao; Gao, Zhuxiu; Huang, Chaoyan

    2017-01-01

    Gyrophase bunched ions were first detected in the upstream region of the Earth's bow shock in the early 1980s which is formed by the microphysical process associated with reflected solar wind ions at the bow shock. Inside the magnetosphere, the results of computer simulations demonstrated that nonlinear wave-particle interaction can also result in the gyrophase bunching of particles. However, to date direct observations barely exist regarding this issue occurred inside the magnetosphere. In this paper, we report for the first time an event of gyrophase bunched ions observed in the near-Earth plasma sheet. The nongyrotropic distributions of ions were closely accompanied with the electromagnetic waves at the oxygen cyclotron frequency. The phase of bunched ions and the phase of waves mainly have very narrow phase differences (<30°) when the O+ band waves are remarkably enhanced, which indicates that the wave and particle are closely corotating. The "electric phase bunching" is considered to be a possible mechanism for the formation of the gyrophase bunched distributions in this case. The MVA analysis suggests that the oxygen band waves possess left helicity with respect to the propagation direction, which agrees with the characteristic of electromagnetic ion cyclotron waves. The observation of O+ ions composition suggests that the oxygen band waves are excited due to the enhancements of the O+ ion density. This study suggests that the gyrophase bunching is a significant nonlinear effect that exists not only in the bow shock but also in the inner magnetosphere.

  11. Sputtering erosion in ion and plasma thrusters

    NASA Technical Reports Server (NTRS)

    Ray, Pradosh K.

    1995-01-01

    An experimental set-up to measure low-energy (below 1 keV) sputtering of materials is described. The materials to be bombarded represent ion thruster components as well as insulators used in the stationary plasma thruster. The sputtering takes place in a 9 inch diameter spherical vacuum chamber. Ions of argon, krypton and xenon are used to bombard the target materials. The sputtered neutral atoms are detected by a secondary neutral mass spectrometer (SNMS). Samples of copper, nickel, aluminum, silver and molybdenum are being sputtered initially to calibrate the spectrometer. The base pressure of the chamber is approximately 2 x 10(exp -9) Torr. the primary ion beam is generated by an ion gun which is capable of delivering ion currents in the range of 20 to 500 nA. The ion beam can be focused to a size approximately 1 mm in diameter. The mass spectrometer is positioned 10 mm from the target and at 90 deg angle to the primary ion beam direction. The ion beam impinges on the target at 45 deg. For sputtering of insulators, charge neutralization is performed by flooding the sample with electrons generated from an electron gun. Preliminary sputtering results, methods of calculating the instrument response function of the spectrometer and the relative sensitivity factors of the sputtered elements will be discussed.

  12. Sputtering erosion in ion and plasma thrusters

    NASA Technical Reports Server (NTRS)

    Ray, Pradosh K.

    1995-01-01

    An experimental set-up to measure low-energy (below 1 keV) sputtering of materials is described. The materials to be bombarded represent ion thruster components as well as insulators used in the stationary plasma thruster. The sputtering takes place in a 9 inch diameter spherical vacuum chamber. Ions of argon, krypton and xenon are used to bombard the target materials. The sputtered neutral atoms are detected by a secondary neutral mass spectrometer (SNMS). Samples of copper, nickel, aluminum, silver and molybdenum are being sputtered initially to calibrate the spectrometer. The base pressure of the chamber is approximately 2 x 10(exp -9) Torr. the primary ion beam is generated by an ion gun which is capable of delivering ion currents in the range of 20 to 500 nA. The ion beam can be focused to a size approximately 1 mm in diameter. The mass spectrometer is positioned 10 mm from the target and at 90 deg angle to the primary ion beam direction. The ion beam impinges on the target at 45 deg. For sputtering of insulators, charge neutralization is performed by flooding the sample with electrons generated from an electron gun. Preliminary sputtering results, methods of calculating the instrument response function of the spectrometer and the relative sensitivity factors of the sputtered elements will be discussed.

  13. Method of ions acceleration for laser-induced implantation of semiconductor materials

    NASA Astrophysics Data System (ADS)

    Czarnecka, A.; Badziak, J.; Parys, P.; Rosinski, M.; Wołowski, J.

    The application of electrostatic fields for the formation of laser-generated ions makes it possible to control the ion stream parameters in broad energy and current density ranges. It also permits to remove the useless ions from the ion stream designed for laser-induced implantation and deposition of layers of semiconductor materials. For acceleration of ions a special electrostatic system has been completed and tested at the Institute of Plasma Physics and Laser Microfusion (IPPLM). A repetitive Nd: glass laser with energy of ˜0.5 J in a 3.5 ns pulse, wavelength of 1.06 μm, repetition rate of up to 10 Hz and intensity on the target of up to 1011 W cm-2, has been recently employed to produce ions emitted from irradiated solid targets. The movable target holder was located inside the cylindrical box connected with a high-voltage source (up to 50 kV). The ions passing through the diaphragm in this box were accelerated in the system of electrodes in the electrostatic field formed in the gap between the box and a grid mounted at the end of the grounded cylindrical electrode. The parameters of the ion streams were measured with the use of several ion collectors and an electrostatic ion energy analyzer (IEA). The Ge ion stream attained energy of up to 30 keV and ion fluency 1011 ions/cm2 for one laser shot. The maximum ion charge state measured with the use of IEA was 3+.

  14. Optical properties of YSZ implanted with Ag ions

    NASA Astrophysics Data System (ADS)

    Saito, Y.; Imamura, Y.; Kitahara, A.

    2003-05-01

    Ag ions were implanted into YSZ (yttria stabilized cubic zirconia) single crystals in both keV and MeV energy regions. For samples with 6 × 10 16 ions/cm 2 at 20 keV, a large absorption peak appears at 536 nm. This absorption peak gradually decreases with increasing temperature. For samples implanted at 3 MeV, a broad absorption peak at around 430 nm was observed. The absorption gradually decreases with increasing temperature, and the sample turns colorless at 700 °C. As the sample is further heated at higher temperatures of 800-1000 °C, a new absorption peak appears at 520 nm and grows with the heating time. This peak appears after several minutes heating at 1000 °C. This absorption peak at 520 nm dose not appear after heating in an Ar atmosphere.

  15. The enhanced anticoagulation for graphene induced by COOH+ ion implantation

    NASA Astrophysics Data System (ADS)

    Liu, Xiaoqi; Cao, Ye; Zhao, Mengli; Deng, Jianhua; Li, Xifei; Li, Dejun

    2015-01-01

    Graphene may have attractive properties for some biomedical applications, but its potential adverse biological effects, in particular, possible modulation when it comes in contact with blood, require further investigation. Little is known about the influence of exposure to COOH+-implanted graphene (COOH+/graphene) interacting with red blood cells and platelets. In this paper, COOH+/graphene was prepared by modified Hummers' method and implanted by COOH+ ions. The structure and surface chemical and physical properties of COOH+/graphene were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and contact angle measurement. Systematic evaluation of anticoagulation, including in vitro platelet adhesion assays and hemolytic assays, proved that COOH+/graphene has significant anticoagulation. In addition, at the dose of 5 × 1017 ions/cm2, COOH+/graphene responded best on platelet adhesion, aggregation, and platelet activation.

  16. Reactive-element effect studied using ion implantation

    SciTech Connect

    King, W.E.; Grabowski, K.S.

    1988-11-01

    Implantation of reactive elements into metals that form chromia layers upon exposure to high temperature oxidizing environments has a very large effect on the growth rate of the oxide and adhesion of the oxide to the base alloy. We have investigated the effect of Y ion implantation on the high temperature oxidation of Fe-24Cr using Rutherford backscattering spectroscopy, secondary ion mass spectroscopy, and electron microscopy. Analytical tools have been applied to determine the spatial distribution of Y, the microstructure of the oxide, and contribution of oxygen transport to the oxidation process. Results are compared with similar experiments in Fe-Cr alloys with Y additions and with results of cation and anion tracer diffusion experiments. 51 refs., 17 figs., 3 tabs.

  17. Synergistic effects of dual Zn/Ag ion implantation in osteogenic activity and antibacterial ability of titanium.

    PubMed

    Jin, Guodong; Qin, Hui; Cao, Huiliang; Qian, Shi; Zhao, Yaochao; Peng, Xiaochun; Zhang, Xianlong; Liu, Xuanyong; Chu, Paul K

    2014-09-01

    Zinc (Zn) and silver (Ag) are co-implanted into titanium by plasma immersion ion implantation. A Zn containing film with Ag nanoparticles (Ag NPs) possessing a wide size distribution is formed on the surface and the corrosion resistance is improved due to the micro-galvanic couples formed by the implanted Zn and Ag. Not only are the initial adhesion, spreading, proliferation and osteogenic differentiation of rBMSCs observed from the Zn/Ag implanted Ti in vitro, but also bacteria killing is achieved both in vitro and in vivo. Electrochemical polarization and ion release measurements suggest that the excellent osteogenic activity and antibacterial ability of the Zn/Ag co-implanted titanium are related to the synergistic effect resulting from the long-range interactions of the released Zn ions and short-range interactions of the embedded Ag NPs. The Zn/Ag co-implanted titanium offers both excellent osteogenic activity and antibacterial ability and has large potential in orthopedic and dental implants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Dual ions implantation of zirconium and nitrogen into magnesium alloys for enhanced corrosion resistance, antimicrobial activity and biocompatibility.

    PubMed

    Cheng, Mengqi; Qiao, Yuqin; Wang, Qi; Qin, Hui; Zhang, Xianlong; Liu, Xuanyong

    2016-12-01

    Biodegradable magnesium-based alloys have shown great potential for medical applications due to their superior biological performances and mechanical properties. However, on one hand, some side effects including inferior biocompatibility, a local high-alkaline environment and gas cavities caused by a rapid corrosion rate, hinder their clinical application. On the other hand, it is also necessary to endow Mg alloys with antibacterial properties, which are crucial for clinic orthopedic applications. In this study, Zr and N ions are simultaneously implanted into AZ91 Mg alloys by plasma immersion ion implantation (PIII). A modified layer with a thickness of approximately 80nm is formed on the surface of AZ91 Mg alloys, and the hydrophobicity and roughness of these AZ91 Mg alloys obviously increase after Zr and N implantation. The in vitro evaluations including corrosion resistance tests, antimicrobial tests and cytocompatibility and alkaline phosphatase (ALP) activity tests, revealed that the dual ions implantation of Zr and N not only enhanced the corrosion resistance of the AZ91 Mg alloy but also provided better antimicrobial properties in vitro. Furthermore, the formation of biocompatible metal nitrides and metal oxides layer in the near surface of the Zr-N-implanted AZ91 Mg alloy provided a favorable implantation surface for cell adhesion and growth, which in return further promoted the bone formation in vivo. These promising results suggest that the Zr-N-implanted AZ91 Mg alloy shows potential for future application in the orthopedic field.

  19. Surface microanalytical studies of nitrogen ion-implanted steel

    NASA Astrophysics Data System (ADS)

    Dodd, Charles G.; Meeker, G. P.; Baumann, Scott M.; Norberg, James C.; Legg, Keith O.

    1985-03-01

    Five types of industrial steels, 1018, 52100, M-2, 440C, and 304 were ion implanted with nitrogen and subjected to surface microanalysis by three independent surface techniques: AES, RBS, and SIMS. The results provided understanding for earlier observations of the properties of various types of steel after nitrogen implantation. The steels that retained the most nitrogen and that have been reported to benefit the most in improved tribological properties from ion implantation were ferritic carbon and austenitic stainless steels, such as soft 1018 and 304, respectively. Heat-treated martensitic carbon steels such as 52100 and M-2 tool steel were found to retain the least nitrogen, and they have been reported to benefit less from nitrogen implantation; however, the interaction of transition metal carbides in M-2 with nitrogen has not been clarified. The data showed that 440C steel retained as much nitrogen as 1018 and 304, but treatment benefits may be limited to improvements in properties related to toughness and impact resistance.

  20. Mechanical properties of ion-implanted tungsten-5 wt% tantalum

    NASA Astrophysics Data System (ADS)

    Armstrong, D. E. J.; Wilkinson, A. J.; Roberts, S. G.

    2011-12-01

    Ion implantation has been used to simulate neutron damage in W-5wt%Ta alloy manufactured by arc melting. Implantations were carried out at damage levels of 0.07, 1.2, 13 and 33 displacements per atom (dpa). The mechanical properties of the ion-implanted layer were investigated by nanoindentation. The hardness increases rapidly from 7.3 GPa in the unimplanted condition to 8.8 GPa at 0.07 dpa. Above this damage level, the increase in hardness is lower, and the hardness change saturates by 13 dpa. In the initial portion of the load-displacement curves, the indentations in unimplanted material show a large 'initial pop-in' corresponding to the onset of plasticity. This is not seen in the implanted samples at any doses. The change in plasticity has also been studied using the nanoindenter in scanning mode to produce a topographical scan around indentations. In the unimplanted condition there is an extensive pile-up around the indentation. At damage levels of 0.07 and 1.2 dpa the extent and height of pile-up are much less. The reasons for this are under further investigation.

  1. Long-ranged order formation of colloids of implanted ions in a dc biased piezoelectric semiconductor

    SciTech Connect

    Salimullah, M.; Rizwan, A.M.; Ghosh, S.K.; Shukla, P.K.; Nambu, M.; Nitta, H.; Hayashi, Y.

    2005-06-15

    A dc bias in a piezoelectric semiconductor may drive a beam of electrons which could charge the neutralized colloids of implanted ions and cause a uniform drift of charged colloidal particles. Using a test particle approach and appropriate dielectric-response function for an n-type piezoelectric semiconductor plasma, the potential distribution of uniformly drifting colloidal ions has been investigated. The dynamical oscillatory wake potential, besides the usual static Coulombian Debye-Hueckel potential, is found to be contributing more dominantly due to the plasma effect, rather than due to electron-phonon coupling interactions. This periodic wakefield may cause a long-range ordered structure of charged colloidal particles within the semiconductor to exhibit various additional properties.

  2. Bubble formation in Zr alloys under heavy ion implantation

    SciTech Connect

    Pagano, L. Jr.; Motta, A.T.; Birtcher, R.C.

    1995-12-01

    Kr ions were used in the HVEM/Tandem facility at ANL to irradiate several Zr alloys, including Zircaloy-2 and -4, at 300-800 C to doses up to 2{times}10{sup 16}ion.cm{sup -2}. Both in-situ irradiation of thin foils as well as irradiation of bulk samples with an ion implanter were used in this study. For the thin foil irradiations, a distribution of small bubbles in the range of 30-100 {angstrom} was found at all temperatures with the exception of the Cr-rich Valloy where 130 {angstrom} bubbles were found. Irradiation of bulk samples at 700-800 C produced large faceted bubbles up to 300 {angstrom} after irradiation to 2{times}10{sup 16}ion.cm{sup -2}. Results are examined in context of existing models for bubble formation and growth in other metals.

  3. Carbon Multicharged Ion Generation from Laser Plasma

    NASA Astrophysics Data System (ADS)

    Balki, Oguzhan; Elsayed-Ali, Hani E.

    2014-10-01

    Multicharged ions (MCI) have potential uses in different areas such as microelectronics and medical physics. Carbon MCI therapy for cancer treatment is considered due to its localized energy delivery to hard-to-reach tumors at a minimal damage to surrounding tissues. We use a Q-switched Nd:YAG laser with 40 ns pulse width operated at 1064 nm to ablate a graphite target in ultrahigh vacuum. A time-of-flight energy analyzer followed by a Faraday cup is used to characterize the carbon MCI extracted from the laser plasma. The MCI charge state and energy distribution are obtained. With increase in the laser fluence, the ion charge states and ion energy are increased. Carbon MCI up to C+6 are observed along with carbon clusters. When an acceleration voltage is applied between the carbon target and a grounded mesh, ion extraction is observed to increase with the applied voltage. National Science Foundation.

  4. Highly antibacterial UHMWPE surfaces by implantation of titanium ions

    NASA Astrophysics Data System (ADS)

    Delle Side, D.; Nassisi, V.; Giuffreda, E.; Velardi, L.; Alifano, P.; Talà, A.; Tredici, S. M.

    2014-07-01

    The spreading of pathogens represents a serious threat for human beings. Consequently, efficient antimicrobial surfaces are needed in order to reduce risks of contracting severe diseases. In this work we present the first evidences of a new technique to obtain a highly antibacterial Ultra High Molecular Weight Polyethylene (UHMWPE) based on a non-stoichiometric titanium oxide coating, visible-light responsive, obtained through ion implantation.

  5. LSI/VLSI Ion Implanted GaAs IC Processing

    DTIC Science & Technology

    1982-02-10

    insulating High Speed Logic Ion Implantation GaAs IC FET Integrated Circuits MESFET 20. ABSTRACT (Coalki. on.. roersie if oookay and IdoeI by WOOe tw**, This...The goal of this program is to realize the full potential of GaAs digital integrated circuits employing depletion mode MESFETs by developing the...Processing. The main objective of this program is to realize the full potential of GaAs digital integrated circuits by expanding and improving

  6. Swept Line Electron Beam Annealing of Ion Implanted Semiconductors.

    DTIC Science & Technology

    1982-07-01

    a pre- liminary study using silicon solar cells. This work was undertaken in cooperation with Dr. J. Eguren of the Instituto De Energia Solar , Madrid...device fabrication has been attempted. To date, resistors, capacitors, diodes, bipolar transistors, MOSFEs, and solar cells have been fabricated with...34 " 48 *Si Solar Cells Ruby PL P+ Ion-Implanted 49 Ruby PL Pulsed Diffused 50 :C

  7. Distribution of Boron Atoms in Ion Implanted Compound Semiconductors

    DTIC Science & Technology

    1988-11-22

    The nondestructive neutron depth profiling (NDP) technique has been used to measure the boron (10B) distributions in GaAs, CdTe, Hg0.7Cd0.3Te, and Hg0.85Mn0.15Te after multiple energy ion implants. The NDP results are found to be in good agreement with the theoretical ion ranges obtained from Monte Carlo computer simulations. Only minor changes in the boron profiles were seen for the chosen annealing conditions. Keywords

  8. The Use of Ion Implantation for Materials Processing.

    DTIC Science & Technology

    1981-06-24

    the Pourbaix diagram ’" for palladium at 25’C as an approximate guide, at zero pH Pd is polarized from a region of immunity into one of corrosion for...to match that of the silicon nitride layers. the most direct indicator was implanted nitrogen ions. To permit calculation of the formation of an...from a reacted, e.g., nitrided , surface layer, or from a more stable microstructure, e.g., nitrogen-stabilized austenite. D. The Effect of Ion

  9. RF characteristics of IHQ linac for heavy ion implantation

    NASA Astrophysics Data System (ADS)

    Ito, Takashi; Osvath, E.; Sasa, Kimikazu; Hayashizaki, Noriyosu; Isokawa, Katsushi; Schubert, H.; Hattori, Toshiyuki

    1998-04-01

    At Tokyo Institute of Technology (TIT), an Interdigital-H type Quadrupole (IHQ) linac has been constructed for application in high energy heavy ion implantation. The linac can accelerate particles with charge to mass ratio greater than 1/16 from 0.24 MeV up to 1.6 MeV (for 16O +). As a result of the low power test, the resonant frequency is 36.26 MHz, the shunt impedance is 252 MΩ/m and therefore, the required power to accelerate 16O + ion is 39.5 kW.

  10. Collimator Magnet with Functionally Defined Profile for Ion Implantation

    SciTech Connect

    Nicolaescu, Dan; Gotoh, Yasuhito; Sakai, Shigeki; Ishikawa, Junzo

    2011-01-07

    Advanced implantation systems used for semiconductor processing should have high precision of ion beam collimation (+/-0.1 deg and better) and wide beam aperture (400 mm and more). Typical arrangements of ion implantation systems include beam scanning (BSM) and collimator magnets (CM). Standard collimator magnets have limited precision of beam collimation due to magnetic poles that have piecewise circular profile. This study proposes a novel ''constant sum angle collimator magnet''(CSACM) with non-circular magnetic pole profile. Angles of incidence {alpha}{sub i} and exit {alpha}{sub e} are defined as angles between ion trajectory and local normal to CM input/output magnetic pole edge. Profile of the CSACM is defined as having constant algebraic sum {alpha}{sub i}+{alpha}{sub e} = const for every ion trajectory of the scanned beam, in addition to ''usual'' beam collimation. An iterative procedure allows improve CSACM taking into account magnetic fringe field effects. Simulation results prove that CSACM assures precise beam collimation in two orthogonal planes. Circular approximations for CSACM magnetic poles are proposed. The model may be further developed for global design of the ion beam line (BSM+CM) and for taking into account space-charge effects.

  11. Modifications in surface, structural and mechanical properties of brass using laser induced Ni plasma as an ion source

    NASA Astrophysics Data System (ADS)

    Ahmad, Shahbaz; Bashir, Shazia; Rafique, M. Shahid; Yousaf, Daniel

    2016-03-01

    Laser induced Ni plasma has been employed as source of ion implantation for surface, structural and mechanical properties of brass. Excimer laser (248 nm, 20 ns, 120mJ and 30 Hz) was used for the generation of Ni plasma. Thomson parabola technique was employed to estimate the energy of generated ions using CR39 as a detector. In response to stepwise increase in number of laser pulses from 3000 to 12000, the ion dose varies from 60 × 1013 to 84 × 1016 ions/cm2 with constant energy of 138 KeV. SEM analysis reveals the growth of nano/micro sized cavities, pores, pits, voids and cracks for the ion dose ranging from 60 × 1013 to 70 × 1015 ions/cm2. However, at maximum ion dose of 84 × 1016 ions/cm2 the granular morphology is observed. XRD analysis reveals that new phase of CuZnNi (200) is formed in the brass substrate after ion implantation. However, an anomalous trend in peak intensity, crystallite size, dislocation line density and induced stresses is observed in response to the implantation with various doses. The increase in ion dose causes to decrease the Yield Stress (YS), Ultimate Tensile Strength (UTS) and hardness. However, for the maximum ion dose the highest values of these mechanical properties are achieved. The variations in the mechanical properties are correlated with surface and crystallographical changes of ion implanted brass.

  12. Europium doping of zincblende GaN by ion implantation

    SciTech Connect

    Lorenz, K.; Franco, N.; Darakchieva, V.; Alves, E.; Roqan, I. S.; O'Donnell, K. P.; Trager-Cowan, C.; Martin, R. W.; As, D. J.; Panfilova, M.

    2009-06-01

    Eu was implanted into high quality cubic (zincblende) GaN (ZB-GaN) layers grown by molecular beam epitaxy. Detailed structural characterization before and after implantation was performed by x-ray diffraction (XRD) and Rutherford backscattering/channeling spectrometry. A low concentration (<10%) of wurtzite phase inclusions was observed by XRD analysis in as-grown samples with their (0001) planes aligned with the (111) planes of the cubic lattice. Implantation of Eu causes an expansion of the lattice parameter in the implanted region similar to that observed for the c-lattice parameter of wurtzite GaN (W-GaN). For ZB-GaN:Eu, a large fraction of Eu ions is found on a high symmetry interstitial site aligned with the <110> direction, while a Ga substitutional site is observed for W-GaN:Eu. The implantation damage in ZB-GaN:Eu could partly be removed by thermal annealing, but an increase in the wurtzite phase fraction was observed at the same time. Cathodoluminescence, photoluminescence (PL), and PL excitation spectroscopy revealed several emission lines which can be attributed to distinct Eu-related optical centers in ZB-GaN and W-GaN inclusions.

  13. Mechanical properties of ion-beam-textured surgical implant alloys

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.

    1977-01-01

    An electron-bombardment Hg ion thruster was used as an ion source to texture surfaces of materials used to make orthopedic and/or dental prostheses or implants. The materials textured include 316 stainless steel, titanium-6% aluminum, 4% vanadium, and cobalt-20% chromium, 15% tungsten. To determine the effect of ion texturing on the ultimate strength and yield strength, stainless steel and Co-Cr-W alloy samples were tensile tested to failure. Three types of samples of both materials were tested. One type was ion-textured (the process also heats each sample to 300 C), another type was simply heated to 300 C in an oven, and the third type was untreated. Stress-strain diagrams, 0.2% offset yield strength data, total elongation data, and area reduction data are presented. Fatigue specimens of ion textured and untextured 316 stainless steel and Ti-6% Al-4% V were tested. Included as an ion textured sample is a Ti-6% Al-4% V sample which was ion machined by means of Ni screen mask so as to produce an array of 140 mu m x 140 mu m x 60 mu m deep pits. Scanning electron microscopy was used to characterize the ion textured surfaces.

  14. Defect engineering in the MOSLED structure by ion implantation

    NASA Astrophysics Data System (ADS)

    Prucnal, S.; Wójtowicz, A.; Pyszniak, K.; Drozdziel, A.; Zuk, J.; Turek, M.; Rebohle, L.; Skorupa, W.

    2009-05-01

    When amorphous SiO2 films are bombarded with energetic ions, various types of defects are created as a consequence of ion-solid interaction (peroxy radicals POR, oxygen deficient centres (ODC), non-bridging oxygen hole centres (NBOHC), E‧ centres, etc.). The intensity of the electroluminescence (EL) from oxygen deficiency centres at 2.7 eV, non-bridging oxygen hole centres at 1.9 eV and defect centres with emission at 2.07 eV can be easily modified by the ion implantation of the different elements (H, N, O) into the completely processed MOSLED structure. Nitrogen implanted into the SiO2:Gd layer reduces the concentration of the ODC and NBOHC while the doping of the oxygen increases the EL intensity observed from POR defect and NBOHC. Moreover, after oxygen or hydrogen implantation into the SiO2:Ge structure fourfold or fifth fold increase of the germanium related EL intensity was observed.

  15. Electrical properties of oxygen ion-implanted InP

    NASA Astrophysics Data System (ADS)

    He, L.; Anderson, W. A.

    1992-10-01

    The effect of oxygen ion implantation on defect levels and the electrical properties of undoped InP ( n-type) and Sn-doped InP have been investigated as a function of postimplant annealing at temperatures of 300 and 400° C. The surface interruption by ion bombardment was studied by a non-invasive optical technique—photoreflectance (PR) spectroscopy. Current-voltage (I-V) characterization and deep level transient spectros-copy (DLTS) were carried out. The free carrier compensation mechanism was studied from the microstructure behavior of defect levels associated with O+ implantation. Free carriers may be trapped in both residual and ion-bombardment-induced defect sites. Rapid thermal annealing (RTA) performed at different temperatures showed that if residual traps were removed by annealing, the compensation efficiency will be enhanced. Post-implant RTA treatment showed that at the higher temperature (400°C), trapped carriers may be re-excited, resulting in a weakened compensation. Comparing the results of undoped and Sn-doped InP indicated that the carrier compensation effect is substrate doping dependent.

  16. Ion beam system for implanting industrial products of various shapes

    NASA Astrophysics Data System (ADS)

    Denholm, A. S.; Wittkower, A. B.

    1985-01-01

    Implantation of metals and ceramics with ions of nitrogen and other species has improved surface properties such as friction, wear and corrosion in numerous industrial applications. Zymet has built a production machine to take advantage of this process which can implant a 2 × 10 17 ions/cm 2 dose of nitrogen ions into a 20 cm × 20 cm area in about 30 min using a 100 keV beam. Treatment is accomplished by mounting the product on a cooled, tiltable, turntable which rotates continuously, or is indexed in 15° steps to expose different surfaces in fixed position. Product cooling is accomplished by using a chilled eutectic metal to mount and grip the variously shaped objects. A high voltage supply capable of 10 mA at 100 kV is used, and the equipment is microcomputer controlled via serial light links. All important machine parameters are presented in sequenced displays on a CRT. Uniformity of treatment and accumulated dose are monitored by a Faraday cup system which provides the microprocessor with data for display of time to completion on the process screen. For routine implants the operator requires only two buttons; one for chamber vacuum control, and the other for process start and stop.

  17. Observations of Ag diffusion in ion implanted SiC

    DOE PAGES

    Gerczak, Tyler J.; Leng, Bin; Sridharan, Kumar; ...

    2015-03-17

    The nature and magnitude of Ag diffusion in SiC has been a topic of interest in connection with the performance of tristructural isotropic (TRISO) coated particle fuel for high temperature gas-cooled nuclear reactors. Ion implantation diffusion couples have been revisited to continue developing a more complete understanding of Ag fission product diffusion in SiC. Ion implantation diffusion couples fabricated from single crystal 4H-SiC and polycrystalline 3C-SiC substrates and exposed to 1500–1625°C, were investigated in this study by transmission electron microscopy and secondary ion mass spectrometry (SIMS). The high dynamic range of SIMS allowed for multiple diffusion régimes to be investigated,more » including enhanced diffusion by implantation-induced defects and grain boundary (GB) diffusion in undamaged SiC. Lastly, estimated diffusion coefficients suggest GB diffusion in bulk SiC does not properly describe the release observed from TRISO fuel.« less

  18. Nanoscale patterns produced by self-sputtering of solid surfaces: The effect of ion implantation

    SciTech Connect

    Bradley, R. Mark; Hofsäss, Hans

    2016-08-21

    A theory of the effect that ion implantation has on the patterns produced by ion bombardment of solid surfaces is introduced. For simplicity, the case of self-sputtering of an elemental material is studied. We find that implantation of self-ions has a destabilizing effect along the projected beam direction for angles of incidence θ that exceed a critical value. In the transverse direction, ion implantation has a stabilizing influence for all θ.

  19. Plasma Wave Observations during Ion Gun Experiments

    DTIC Science & Technology

    1990-03-20

    Spacecraft Charging by Magnetospheric Plasma , Progress in Aeronautics and Astronautics , Vol. 47, ed. A. Rosen, IAA, pp. 15-30 (1976). 3. H. C. Koons, P. F...AIAA 75-92 (January 20-22, 1975). 2. D. A. McPherson and W. R. Schober, " Spacecraft Charging at High Altitudes: The SCATHA Satellite Program," in...on the AF/NASI P78-2 (SCATHA) satellite were conducted with a plasma /ion source in the inner magnetosphere . These experiments were monitored with

  20. Plasma Surface Functionalized Polyetheretherketone for Enhanced Osseo-Integration at Bone-Implant Interface.

    PubMed

    Zhao, Ying; Wong, Hoi Man; Lui, So Ching; Chong, Eva Y W; Wu, Guosong; Zhao, Xiaoli; Wang, Chong; Pan, Haobo; Cheung, Kenneth M C; Wu, Shuilin; Chu, Paul K; Yeung, Kelvin W K

    2016-02-17

    This study aims at improving osseo-integration at the bone-implant interface of polyetheretherketone (PEEK) by water (H2O) and ammonia (NH3) plasma immersion ion implantation (PIII). The pertinent surface characteristics including surface energy, roughness, morphology, and chemical composition are investigated systematically and the in vitro biological performance is evaluated by cell adhesion and proliferation, alkaline phosphatase (ALP) activity, real-time RT-PCR evaluation, and mineralization tests. In vivo osseo-integration is examined via implanting samples into the distal femur of the rats. The hydrophilicity, surface roughness, cell adhesion, and proliferation, ALP activity, and osteogenic differentiation after H2O PIII or NH3 PIII are improved significantly. Furthermore, substantially enhanced osseo-integration is achieved in vivo. Nonline-of-sight plasma surface functionalization, which is particularly suitable for biomedical implants with an irregular geometry, does not alter the bulk compressive yield strength and elastic modulus of the materials. Consequently, the favorable bulk attributes of PEEK are preserved while the surface biological properties are enhanced thus boding well for wider orthopedic application of the biopolymer.