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Sample records for ion implantation effects

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Effect of ion implantation on the corrosion behavior of a high-density sintered tungsten alloy

    SciTech Connect

    Chang, F.C.; Levy, M.; Lin, S.S.

    1987-08-01

    The effect of chromium, nickel, tantalum, and titanium ion implantation on the electrochemical corrosion behavior of a high-density sintered tungsten alloy was investigated in C1/sup -/ -free and chlorine-ion containing aqueous solution buffered to pH values of 4, 9, and 12. A three sweep potentiodynamic polarization technique was used to compare the polarization behavior of unimplanted and implanted surfaces. The surfaces of the ion-implanted tungsten alloy were characterized by Auger electron spectroscopic (AES) analysis.

  13. Effectiveness of ion implantation of iron garnet films

    SciTech Connect

    Tikhonov, A.N.; Fedichkin, G.M.; Yurchenko, S.E.; Suslin, L.A.; Smirnov, I.S.; Shlenov, Yu.V.

    1986-01-01

    The authors seek to determine experimentally what changes of the magnetic bubble properties and of the iron garnet film characteristics resulting from implantation of Ne/sup +/ ions can be used as criteria for assessing the effectiveness of this process in the production of bubble devices. For the experiments, the authors used (YBi)/sub 3/(FeGa)/sub 5/O/sub 12/; (TmBi)/sub 3/(FeGa)/sub 5/O/sub 12/; and (YSmLuCa)/sub 3/(FeGe)/sub 5/O/sub 12/. The orientation of the Gd/sub 3/Ga/sub 5/O/sub 12/ substrate is (111) in all cases. The current density of the H/sup +/ proton beam did not exceed 0.5 micro-A/cm/sup 2/.

  14. 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.

  15. 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.

  16. Effect of phosphorous ion implantation on the mechanical properties and bioactivity of hydroxyapatite.

    PubMed

    Kobayashi, Satoshi; Muramatsu, Takehiro; Teranishi, Yoshikazu

    2015-01-01

    Hydroxyapatite (HA) has ability of bone-like apatite formation, which consists with chemical interaction between the surface of HA and ions included in body fluid. Thus, proper surface modification might enhance the function. In the present study, the effect of phosphorous ion implantation on mechanical properties and bioactivity of HA was investigated. In order to clarify the effect of ion implantation dose, ion dose of 1 × 10(12), 1 × 10(13) and 1 × 10(14) ions/cm(2) were selected. Mechanical properties and bioactivity were evaluated in 4-point bending tests and immersion test in simulated body fluid. Bending strength was reduced due to ion implantation. The amount of decreasing strength was similar regardless of ion implantation dose. Bone-like apatite formation was slightly delayed with ion implantation, however, improvement in interfacial strength between bone-like apatite layer and the base HA was indicated. From the results, the possibility of phosphorous ion implantation for enhancement of bioactivity of HA was proved.

  17. Shape memory effect and superelasticity of titanium nickelide alloys implanted with high ion doses

    NASA Astrophysics Data System (ADS)

    Pogrebnjak, A. D.; Bratushka, S. N.; Beresnev, V. M.; Levintant-Zayonts, N.

    2013-12-01

    The state of the art in ion implantation of superelastic NiTi shape memory alloys is analyzed. Various technological applications of the shape memory effect are outlined. The principles and techiques of ion implantation are described. Specific features of its application for modification of surface layers in surface engineering are considered. Key properties of shape memory alloys and problems in utilization of ion implantation to improve the surface properties of shape memory alloys, such as corrosion resistance, friction coefficient, wear resistance, etc. are discussed. The bibliography includes 162 references.

  18. Long-range effect of ion implantation of Raex and Hardox steels

    NASA Astrophysics Data System (ADS)

    Budzyński, P.; Kamiński, M.; Droździel, A.; Wiertel, M.

    2016-09-01

    Ion implantation involves introduction of ionized atoms of any element (nitrogen) to metals thanks to the high kinetic energy that they acquired in the electric field. The distribution of nitrogen ions implanted at E = 65 keV energy and D = 1.1017 N+ /cm2 fluence in the steel sample and vacancies produced by them was calculated using the SRIM program. This result was confirmed by RBS measurements. The initial maximum range of the implanted nitrogen ions is ∼⃒0.17 μm. This value is relatively small compared to the influence of nitriding on the thickness surface layer of modified steel piston rings. Measurements of the friction coefficient during the pin-on-disc tribological test were performed under dry friction conditions. The friction coefficient of the implanted sample increased to values characteristic of an unimplanted sample after ca. 1500 measurement cycles. The depth of wear trace is ca. 2.4 μm. This implies that the thickness of the layer modified by the implantation process is ∼⃒2.4 μm and exceeds the initial range of the implanted ions by an order of magnitude. This effect, referred to as a long-range implantation effect, is caused by migration of vacancies and nitrogen atoms into the sample. This phenomenon makes ion implantation a legitimate process of modification of the surface layer in order to enhance the tribological properties of critical components of internal combustion engines such as steel piston rings.

  19. Nonlinear damage effect in graphene synthesis by C-cluster ion implantation

    SciTech Connect

    Zhang Rui; Zhang Zaodi; Wang Zesong; Wang Shixu; Wang Wei; Fu Dejun; Liu Jiarui

    2012-07-02

    We present few-layer graphene synthesis by negative carbon cluster ion implantation with C{sub 1}, C{sub 2}, and C{sub 4} at energies below 20 keV. The small C-clusters were produced by a source of negative ion by cesium sputtering with medium beam current. We show that the nonlinear effect in cluster-induced damage is favorable for graphene precipitation compared with monomer carbon ions. The nonlinear damage effect in cluster ion implantation shows positive impact on disorder reduction, film uniformity, and the surface smoothness in graphene synthesis.

  20. The effect of sodium-ion implantation on the properties of titanium.

    PubMed

    Baszkiewicz, J; Krupa, D; Kozubowski, J A; Rajchel, B; Lewandowska-Szumieł, M; Barcz, A; Sobczak, J W; Kosiński, A; Chróścicka, A

    2008-09-01

    This paper deals with the surface modification of titanium by sodium-ion implantation and with the effect of this modification on structure, corrosion resistance, bioactivity and cytocompatibility. The Na ions were implanted with doses of 1 x 10(17) and 4 x 10(17) ions/cm(2) at an energy of 25 keV. The chemical composition of the surface layers formed during the implantation was examined by secondary-ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS), and their microstructure--by transmission electron microscopy (TEM). The corrosion resistance was determined by electrochemical methods in a simulated body fluid (SBF) at a temperature of 37 degrees C, after exposure in SBF for various times. The surfaces of the samples were examined by optical microscopy, by scanning electron microscopy (SEM-EDS), and by atomic force microscopy (AFM). Biocompatibility of the modified surface was evaluated in vitro in a culture of the MG-63 cell line and human osteoblast cells. The TEM results indicate that the surface layers formed during the implantation of Na-ions are amorphous. The results of the electrochemical examinations obtained for the Na-implanted titanium samples indicate that the implantation increases corrosion resistance. Sodium-ion implantation improves bioactivity and does not reduce biocompatibility.

  1. 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.

  2. [Study on effect of seed vigor and agronomic characters of Cassia seeds implanted with low energy nitrogen ion beans].

    PubMed

    Song, Mei; Wang, Xiang-Yang

    2012-07-01

    To study the effect of low energy nitrogen ion implantation on seed germination and agronomic characters. Different doses of low energy nitrogen ion implantation were implanted into fresh Cassia seed embryos. Seed germination, seedling growth and field agronomic characters were observed. The seeds after ion implantation showed significant reduction in germination energy, germination percentage and germination index, besides the significant decreasement in root length, fresh weight and vigor index of seedling. Plant height decreased despite the increase in grain size and grain weight. The low energy nitrogen ion implantation have significant effect on Cassia seeds, and being of great significance on Cassia artificial cultivation.

  3. The Effect of Ag and Ag+N Ion Implantation on Cell Attachment Properties

    SciTech Connect

    Urkac, Emel Sokullu; Oztarhan, Ahmet; Gurhan, Ismet Deliloglu; Iz, Sultan Gulce; Tihminlioglu, Funda; Oks, Efim; Nikolaev, Alexey; Ila, Daryush

    2009-03-10

    Implanted biomedical prosthetic devices are intended to perform safely, reliably and effectively in the human body thus the materials used for orthopedic devices should have good biocompatibility. Ultra High Molecular Weight Poly Ethylene (UHMWPE) has been commonly used for total hip joint replacement because of its very good properties. In this work, UHMWPE samples were Ag and Ag+N ion implanted by using the Metal-Vapor Vacuum Arc (MEVVA) ion implantation technique. Samples were implanted with a fluency of 1017 ion/cm2 and extraction voltage of 30 kV. Rutherford Backscattering Spectrometry (RBS) was used for surface studies. RBS showed the presence of Ag and N on the surface. Cell attachment properties investigated with model cell lines (L929 mouse fibroblasts) to demonstrate that the effect of Ag and Ag+N ion implantation can favorably influence the surface of UHMWPE for biomedical applications. Scanning electron microscopy (SEM) was used to demonstrate the cell attachment on the surface. Study has shown that Ag+N ion implantation represents more effective cell attachment properties on the UHMWPE surfaces.

  4. Annealing effects on the migration of ion-implanted cadmium in glassy carbon

    NASA Astrophysics Data System (ADS)

    Hlatshwayo, T. T.; Sebitla, L. D.; Njoroge, E. G.; Mlambo, M.; Malherbe, J. B.

    2017-03-01

    The migration behaviour of cadmium (Cd) implanted into glassy carbon and the effects of annealing on radiation damage introduced by ion implantation were investigated. The glassy carbon substrates were implanted with Cd at a dose of 2 × 1016 ions/cm2 and energy of 360 keV. The implantation was performed at room temperature (RT), 430 °C and 600 °C. The RT implanted samples were isochronally annealed in vacuum at 350, 500 and 600 °C for 1 h and isothermally annealed at 350 °C up to 4 h. The as-implanted and annealed samples were characterized by Raman spectroscopy and Rutherford backscattering spectrometry (RBS). Raman results revealed that implantation at room temperature amorphized the glassy carbon structure while high temperature implantations resulted in slightly less radiation damage. Isochronal annealing of the RT implanted samples resulted in some recrystallization as a function of increasing temperature. The original glassy carbon structure was not achieved at the highest annealing temperature of 600 °C. Diffusion of Cd in glassy carbon was already taking place during implantation at 430 °C. This diffusion of Cd was accompanied by significant loss from the surface during implantation at 600 °C. Isochronal annealing of the room temperature implanted samples at 350 °C for 1 h caused Cd to diffuse towards the bulk while isothermal annealing at 500 and 600 °C resulted in the migration of implanted Cd toward the surface accompanied by a loss of Cd from the surface. Isothermal annealing at 350 °C for 1 h caused Cd to diffuse towards the bulk while for annealing time >1 h Cd diffused towards the surface. These results were interpreted in terms of trapping and de-trapping of implanted Cd by radiation damage.

  5. 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.

  6. 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.

  7. Long-range effect in nitrogen ion-implanted AISI 316L stainless steel

    NASA Astrophysics Data System (ADS)

    Budzynski, P.

    2015-01-01

    The effect of nitrogen ion implantation on AISI 316L stainless steel was investigated. The microstructure and composition of an N implanted layer were studied by RBS, GIXRD, SEM, and EDX measurements. Friction and wear tests were also performed. The discrepancy between the measured and calculated stopped ion maximum range does not exceed 0.03 μm. After nitrogen implantation with a fluence of 5 × 1017 ion/cm2, additional phases of expanded austenite were detected. At a 5-fold larger depth than the maximum ion range, improvement in the coefficient of friction and wear was detected. We have shown, for the first time, the long-range effect in tribological investigations. The long-range effect is caused by movement of not only defects along the depth of the sample, as assumed so far, but also nitrogen atoms.

  8. 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.

  9. Synergistic Effects of Iodine and Silver Ions Co-Implanted in 6H-SiC

    SciTech Connect

    Kuhudzai, Remeredzai J.; Malherbe, Johan; Hlatshwayo, T. T.; van der Berg, N. G.; Devaraj, Arun; Zhu, Zihua; Nandasiri, Manjula I.

    2015-10-23

    Motivated by the aim of understanding the release of fission products through the SiC coating of fuel kernels in modern high temperature nuclear reactors, a fundamental investigation is conducted to understand the synergistic effects of implanted silver (Ag) and iodine (I) in 6H-SiC. The implantation of the individual species, as well as the co-implantation of 360 keV ions of I and Ag at room temperature in 6H-SiC and their subsequent annealing behavior has been investigated by Secondary Ion Mass Spectrometry (SIMS), Atom Probe Tomography (APT) and X-ray Photoelectron Spectroscopy (XPS). SIMS and APT measurements indicated the presence of Ag in the co-implanted samples after annealing at 1500 ºC for 30 hours in sharp contrast to the samples implanted with Ag only. In samples implanted with Ag only, complete loss of the implanted Ag was observed. However, for I only implanted samples, some iodine was retained. APT of annealed co-implanted 6H-SiC showed clear spatial association of Ag and I clusters in SiC, which can be attributed to the observed I assisted retention of Ag after annealing. Such detailed studies will be necessary to identify the fundamental mechanism of fission products migration through SiC coatings.

  10. Germanium ion implantation to Improve Crystallinity during Solid Phase Epitaxy and the effect of AMU Contamination

    SciTech Connect

    Lee, K. S.; Yoo, D. H.; Son, G. H.; Lee, C. H.; Noh, J. H.; Han, J. J.; Yu, Y. S.; Hyung, Y. W.; Kim, Y. K.; Lee, S. C.; Lee, H. D.; Moon, J. T.; Yang, J. K.; Song, D. G.; Lim, T. J.

    2006-11-13

    Germanium ion implantation was investigated for crystallinity enhancement during solid phase epitaxial regrowth (SPE) using high current implantation equipment. Electron back-scatter diffraction(EBSD) measurement showed numerical increase of 19 percent of <100> signal, which might be due to pre-amorphization effect on silicon layer deposited by LPCVD process with germanium ion implantation. On the other hand, electrical property such as off-leakage current of NMOS transistor degraded in specific regions of wafers, which implied non-uniform distribution of donor-type impurities into channel area. It was confirmed that arsenic atoms were incorporated into silicon layer during germanium ion implantation. Since the equipment for germanium pre-amorphization implantation(PAI) was using several source gases such as BF3 and AsH3, atomic mass unit(AMU) contamination during PAI of germanium with AMU 74 caused the incorporation of arsenic with AMU 75 which resided in arc-chamber and other parts of the equipment. It was effective to use germanium isotope of AMU 72 to suppress AMU contamination, however it led serious reduction of productivity because of decrease in beam current by 30 percent as known to be difference in isotope abundance. It was effective to use enriched germanium source gas with AMU 72 in order to improve productivity. Spatial distribution of arsenic impurities in wafers was closely related to hardware configuration of ion implantation equipment.

  11. Annealing effect on planar waveguides in LiNbO 3 produced by oxygen ion implantation

    NASA Astrophysics Data System (ADS)

    Liu, Xiu-Hong; Huang, Qing; Zhao, Jin-Hua; Liu, Peng; Wang, Xue-Lin; Du, Ji-Fu; Huang, Ning-Kang

    2011-01-01

    We reported on planar waveguides in stoichiometric lithium niobate fabricated by 4.5 MeV oxygen ion implantation with a dose of 6 × 10 14 ions/cm 2 at room temperature. After ion implantation, these samples were annealed at 240 °C, 260 °C, and 300 °C for 30 min. We investigated annealing effect on the guiding modes and near-field images in the waveguides by prism-coupling method and end-face coupling method respectively. We found that for the extraordinary refractive index a positive alternation occurred in the near-surface region while a negative alternation happened at the end of ion track. Moreover, we measured the transmission spectra for the pure sample and implanted samples before and after annealed at different temperatures, and we observed an absorption peak at ˜480 nm (2.6 eV) in all of these SLN samples.

  12. 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.

  13. 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.

  14. Irradiation effect of carbon negative-ion implantation on polytetrafluoroethylene for controlling cell-adhesion property

    NASA Astrophysics Data System (ADS)

    Sommani, Piyanuch; Tsuji, Hiroshi; Kojima, Hiroyuki; Sato, Hiroko; Gotoh, Yasuhito; Ishikawa, Junzo; Takaoka, Gikan H.

    2010-10-01

    We have investigated the irradiation effect of negative-ion implantation on the changes of physical surface property of polytetrafluoroethylene (PTFE) for controlling the adhesion property of stem cells. Carbon negative ions were implanted into PTFE sheets at fluences of 1 × 10 14-1 × 10 16 ions/cm 2 and energies of 5-20 keV. Wettability and atomic bonding state including the ion-induced functional groups on the modified surfaces were investigated by water contact angle measurement and XPS analysis, respectively. An initial value of water contact angles on PTFE decreased from 104° to 88° with an increase in ion influence to 1 × 10 16 ions/cm 2, corresponding to the peak shifting of XPS C1s spectra from 292.5 eV to 285 eV with long tail on the left peak-side. The change of peak position was due to decrease of C-F 2 bonds and increase of C-C bonds with the formation of hydrophilic oxygen functional groups of OH and C dbnd O bonds after the ion implantation. After culturing rat mesenchymal stem cells (MSC) for 4 days, the cell-adhesion properties on the C --patterned PTFE were observed by fluorescent microscopy with staining the cell nuclei and their actin filament (F-actin). The clear adhesion patterning of MSCs on the PTFE was obtained at energies of 5-10 keV and a fluence of 1 × 10 15 ions/cm 2. While the sparse patterns and the uncontrollable patterns were found at a low fluence of 3 × 10 14 ions/cm 2 and a high fluence of 3 × 10 15 ions/cm 2, respectively. As a result, we could improve the surface wettability of PTFE to control the cell-adhesion property by carbon negative-ion implantation.

  15. Effect of nitrogen ion implantation on the flexibility of rotary nickel-titanium instruments.

    PubMed

    dos Santos, Marcelo; Gavini, Giulio; Siqueira, Evandro Luiz; da Costa, Cristiane

    2012-05-01

    The aim of this study was to assess the effect of nitrogen ion implantation on the flexibility of rotary nickel-titanium (NiTi) instruments as measured by the load required to bend implanted and nonimplanted instruments at a 30° angle. Thirty K3 files, size #40, 0.02 taper and 25-mm length, were allocated into 2 groups as follows: group A, 15 files exposed to nitrogen ion implantation at a dose of 2.5 × 10(17) ions/cm(2), voltage 200 KeV, current density 1 μA/cm(2), temperature 130°C, and vacuum conditions of 10 × 10(-6) mm Hg for 6 hours; and group B, 15 nonimplanted files. One extra file was used for process control. All instruments were subjected to bend testing on a modified troptometer, with measurement of the load required for flexure to an angle of 30°. The Mann-Whitney U test was used for statistical analysis. Findings with P <.05 were considered significant. The mean load required to bend instruments at a 30° angle was 376.26 g for implanted instruments and 383.78 g for nonimplanted instruments. The difference was not statistically significant. Our findings show that nitrogen ion implantation has no appreciable effect on the flexibility of NiTi instruments. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Ion-implantation effect on time-dependent breakdown in SiO2

    NASA Technical Reports Server (NTRS)

    Li, S. P.

    1975-01-01

    It was experimentally demonstrated that the field emission of positive ions from the metal SiO2 interface in MOS structures can be controlled by introducing a positive charge in a small ion-implantation dose to a shallow depth below the metal electrode. Considerable improvement of time-dependent breakdown was noted in structures implanted in this manner as opposed to nonimplanted ones. This experiment confirms the model proposed by Li and Maserjian (1975) for radiation effect on time-dependent breakdown.

  17. Effect of ion-implantation enhanced intermixing on luminescence of InAs/InP quantum dots

    NASA Astrophysics Data System (ADS)

    Li, Q.; Barik, S.; Tan, H. H.; Jagadish, C.

    2008-10-01

    Temperature dependent photoluminescence spectra of ion implanted InAs/InP quantum dots (QDs) followed by rapid thermal annealing were studied. By employing a recently developed luminescence model for localized states ensemble, the broadening of the distribution of the localized QD states was determined from the fitting to the luminescence peak energy positions. The broadening of the distribution of the localized QD states reduces due to ion-implantation enhanced intermixing. The contribution of carrier distribution within the localized QD states to the luminescence linewidth decreases after ion-implantation enhanced intermixing. The effect of doses and types of ions used for implantation were also investigated.

  18. Effect of phosphorus ion implantation on back gate effect of partially depleted SOI NMOS under total dose radiation

    NASA Astrophysics Data System (ADS)

    Leilei, Li; Xinjie, Zhou; Zongguang, Yu; Qing, Feng

    2015-01-01

    The mechanism of improving the TID radiation hardened ability of partially depleted silicon-on-insulator (SOI) devices by using the back-gate phosphorus ion implantation technology is studied. The electron traps introduced in SiO2 near back SiO2/Si interface by phosphorus ions implantation can offset positive trapped charges near the back-gate interface. The implanted high concentration phosphorus ions can greatly reduce the back-gate effect of a partially depleted SOI NMOS device, and anti-total-dose radiation ability can reach the level of 1 Mrad(Si) for experimental devices.

  19. Grain size effect on yield strength of titanium alloy implanted with aluminum ions

    SciTech Connect

    Popova, Natalya; Yurev, Ivan; Kalashnikov, Mark

    2016-01-15

    The paper presents a transmission electron microscopy (TEM) study of the microstructure and phase state of commercially pure titanium VT1-0 implanted by aluminum ions. This study has been carried out before and after the ion implantation for different grain size, i.e. 0.3 µm (ultra-fine grain condition), 1.5 µm (fine grain condition), and 17 µm (polycrystalline condition). This paper presents details of calculations and analysis of strength components of the yield stress. It is shown that the ion implantation results in a considerable hardening of the entire thickness of the implanted layer in the both grain types. The grain size has, however, a different effect on the yield stress. So, both before and after the ion implantation, the increase of the grain size leads to the decrease of the alloy hardening. Thus, hardening in ultra-fine and fine grain alloys increased by four times, while in polycrystalline alloy it increased by over six times.

  20. Grain size effect on yield strength of titanium alloy implanted with aluminum ions

    NASA Astrophysics Data System (ADS)

    Popova, Natalya; Nikonenko, Elena; Yurev, Ivan; Kalashnikov, Mark; Kurzina, Irina

    2016-01-01

    The paper presents a transmission electron microscopy (TEM) study of the microstructure and phase state of commercially pure titanium VT1-0 implanted by aluminum ions. This study has been carried out before and after the ion implantation for different grain size, i.e. 0.3 µm (ultra-fine grain condition), 1.5 µm (fine grain condition), and 17 µm (polycrystalline condition). This paper presents details of calculations and analysis of strength components of the yield stress. It is shown that the ion implantation results in a considerable hardening of the entire thickness of the implanted layer in the both grain types. The grain size has, however, a different effect on the yield stress. So, both before and after the ion implantation, the increase of the grain size leads to the decrease of the alloy hardening. Thus, hardening in ultra-fine and fine grain alloys increased by four times, while in polycrystalline alloy it increased by over six times.

  1. 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.

  2. Effect of nitrogen ion implantation on the structural and optical properties of indium oxide thin films

    SciTech Connect

    Sethi, Riti; Aziz, Anver; Siddiqui, Azher M.; Kumar, Pravin; Khan, Sameen Ahmed

    2016-06-10

    : We report here synthesis and subsequent nitrogen ion implantation of indium oxide (In{sub 2}O{sub 3}) thin films. The films were implanted with 25 keV N{sup +} beam for different ion doses between 3E15 to 1E16 ions/cm{sup 2}. The resulting changes in structural and optical properties were investigated using XRD, SEM-EDAX and UV-Vis Spectrometry. XRD studies reveal decrease in crystallite size from 20.06 to 12.42 nm with increase in ion dose. SEM micrographs show an increase in the grain size from 0.8 to 1.35 µm with increase in ion dose because of the agglomeration of the grains. Also, from EDAX data on pristine and N-implanted thin films the presence of indium and oxygen without any traces of impurity elements could be seen. However, at lower ion doses such as 3E15 and 5E15 ions/cm{sup 2}, no evidence of the presence of nitrogen ion was seen. However, for the ion dose of 1E16 ions/cm{sup 2}, evidence of presence of nitrogen can be seen in the EDAX data. Band gap calculations reveal a decrease in band gap from 3.54 to 3.38 eV with increasing ion dose. However, the band gap was found to again show an increase to 3.58 eV at the highest ion dose owing to quantum confinement effect.

  3. Study of Biological Effects of Low Energy Ion Implantation on Tomato and Radish Breeding

    NASA Astrophysics Data System (ADS)

    Liang, Qiuxia; Huang, Qunce; Cao, Gangqiang; Ying, Fangqing; Liu, Yanbo; Huang, Wen

    2008-04-01

    Biological effects of 30 keV low energy nitrogen ion implantation on the seeds of five types of tomato and one type of radish were investigated. Results showed that low energy ions have different effects on different vegetables. The whole dose-response curve of the germination ratio did not take on "the shape of saddle", but was a rising and falling waveform with the increase or decrease in ion implantation. In the vegetable of Solanaceae, two outstanding aberrant plants were selected from M1 of Henan No.4 tomato at a dose of 7 × 1017 nitrogen ions/cm2, which had thin-leaves, long-petal and nipple tip fruit stably inherited to M7. Furthermore the analysis of the isozyme showed that the activity of the mutant tomato seedling was distinct in quantity and color. In Raphanus sativus L., the aberrances were obvious in the mutant of radish 791 at a dose of 5 × 1017 nitrogen ions/cm2, and the weight of succulent root and the volume of growth were over twice the control's. At present, many species for breeding have been identified in the field and only stable species have been selected for the experiment of production. It is evident that the low energy ion implantation technology has clear effects on vegetables' genetic improvement.

  4. The damaging effects of nitrogen ion beam implantation on upland cotton ( Gossypium hirsutum L.) pollen grains

    NASA Astrophysics Data System (ADS)

    Yu, Yanjie; Wu, Lijun; Wu, Yuejin; Wang, Qingya; Tang, Canming

    2008-09-01

    With the aim to study the effects of an ion beam on plant cells, upland cotton (Gossypium hirsutum L.) cultivar "Sumian 22" pollen grains were irradiated in vacuum (7.8 × 10-3 Pa) by low-energy nitrogen ions with an energy of 20 keV at various fluences ranging from 0.26 × 1016 to 0.78 × 1016 N+/cm2. The irradiation effects on pollen grains were tested, considering the ultrastructural changes in the exine and interior walls of pollen grains, their germination rate, the growth speed of the pollen tubes in the style, fertilization and boll development after the pistils were pollinated by the pollen grains which had been implanted with nitrogen ions. Nitrogen ions entered the pollen grains by etching and penetrating the exine and interior walls and destroying cell structures. A greater percentage of the pollen grains were destroyed as the fluence of N+ ions increased. Obviously, the nitrogen ion beam penetrated the exine and interior walls of the pollen grains and produced holes of different sizes. As the ion fluence increased, the amount and the density of pollen grain inclusions decreased and the size of the lacuna and starch granules increased. Pollen grain germination rates decreased with increasing ion fluence. The number of pollen tubes in the style declined with increased ion implantation into pollen grains, but the growth speed of the tubes did not change. All of the pollen tubes reached the end of the style at 13 h after pollination. This result was consistent with that of the control. Also, the weight and the diameter of the ovary decreased and shortened with increased ion beam implantation fluence. No evident change in the fecundation time of the ovule was observed. These results indicate that nitrogen ions can enter pollen grains and cause a series of biological changes in pollen grains of upland cotton.

  5. The channeling effect of Al and N ion implantation in 4H-SiC during JFET integrated device processing

    NASA Astrophysics Data System (ADS)

    Lazar, M.; Laariedh, F.; Cremillieu, P.; Planson, D.; Leclercq, J.-L.

    2015-12-01

    A strong channeling effect is observed for the ions of Al and N implanted in 4H-SiC due to its crystalline structure. This effect causes difficulties in subsequent accurate estimation of the depth of junctions formed by multiple ion implantation steps. A variety of lateral JFET transistors integrated on the same 4H-SiC wafer have been fabricated. Secondary Ion Mass Spectrometry measurements and Monte-Carlo simulations were performed in order to quantify and control the channeling effect of the implanted ions. A technological process was established enabling to obtain devices working with the presence of the channeling effect.

  6. 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.

  7. 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

  8. Dose rate effects on damage formation in ion-implanted gallium arsenide

    SciTech Connect

    Haynes, T.E.; Holland, O.W.

    1990-09-01

    The residual damage in GaAs was measured by ion channeling following implantation of either 100 keV {sup 30}Si{sup +} at temperatures of 300K or 77K, or 360 keV {sup 120}Sn{sup +} at 300K. For room-temperature Si implants and fluences between 1 and 10 {times} 10{sup 14} Si/cm{sup 2}, the amount of damage created was strongly dependent upon the ion current density, which was varied between 0.05 and 12 {mu}A/cm{sup 2}. Two different stages of damage growth were identified by an abrupt increase in the damage growth rate as a function of fluence, and the threshold fluence for the onset of the second stage was found to be dependent on the dose rate. The dose rate effect on damage was substantially weaker for {sup 120}Sn{sup +} implants and was negligible for Si implants at 77K. The damage was found to be most sensitive to the average current density, demonstrating that the defects which are the precursors to the residual dose-rate dependent damage have active lifetimes of at least 3 {times} 10{sup {minus}4} s. The dose rate effect and its variation with ion mass and temperature are discussed in the context of homogeneous nucleation and growth of damage during ion irradiation.

  9. Effects of ion implantation on friction and wear of stainless steels. [15-5PH

    SciTech Connect

    Pope, L.E.; Yost, F.G.; Follstaedt, D.M.; Knapp, J.A.; Picraux, S.T.

    1982-01-01

    Friction and wear of 304, 15-5 PH and 440C stainless steels and of pure Fe are shown to be reduced by ion implantation of Ti and C. Mechanically polished samples were ion implanted to fluences of 2 x 10/sup 15/ Ti/mm/sup 2/ (90 to 180 keV) and 2 x 10/sup 15/ C/mm/sup 2/ (30 keV); the implantation profiles of the two elements extended to approx. 0.1 ..mu..m and approximately overlapped each other. The effects of normal load (Hertzian stresses in the range of 690 to 1840 MPa) on friction and wear were evaluated in the pin-on-disc configuration with no lubrication. 304 pins were used and are shown to give results similar to those previously reported for 440C pins. Ion implantation reduces friction coefficients by up to 80% and decreases the maximum wear depths by up to 95%, but the magnitude of reductions depends on the material and the load conditions. Transfer of material containing Ti from the implanted plates to both 304 and 440C pins was observed. A change in wear mechanism was detected in the wear tracks as the load was increased: fine-scale abrasive-type parallel grooves were present at light loads while galling was observed at high loads. 6 figures.

  10. Effect of exposure environment on surface decomposition of SiC-silver ion implantation diffusion couples

    DOE PAGES

    Gerczak, Tyler J.; Zheng, Guiqui; Field, Kevin G.; ...

    2014-10-05

    SiC is a promising material for nuclear applications and is a critical component in the construction of tristructural isotropic (TRISO) fuel. A primary issue with TRISO fuel operation is the observed release of 110m Ag from intact fuel particles. The release of Ag has prompted research efforts to directly measure the transport mechanism of Ag in bulk SiC. Recent research efforts have focused primarily on Ag ion implantation designs. The effect of the thermal exposure system on the ion implantation surface has been investigated. Results indicate the utilization of a mated sample geometry and the establishment of a static thermalmore » exposure environment is critical to maintaining an intact surface for diffusion analysis. In conclusion, the nature of the implantation surface and its potential role in Ag diffusion analysis are discussed.« less

  11. Effect of exposure environment on surface decomposition of SiC-silver ion implantation diffusion couples

    SciTech Connect

    Gerczak, Tyler J.; Zheng, Guiqui; Field, Kevin G.; Allen, Todd R.

    2014-10-05

    SiC is a promising material for nuclear applications and is a critical component in the construction of tristructural isotropic (TRISO) fuel. A primary issue with TRISO fuel operation is the observed release of 110m Ag from intact fuel particles. The release of Ag has prompted research efforts to directly measure the transport mechanism of Ag in bulk SiC. Recent research efforts have focused primarily on Ag ion implantation designs. The effect of the thermal exposure system on the ion implantation surface has been investigated. Results indicate the utilization of a mated sample geometry and the establishment of a static thermal exposure environment is critical to maintaining an intact surface for diffusion analysis. In conclusion, the nature of the implantation surface and its potential role in Ag diffusion analysis are discussed.

  12. Ion beam sputter etching of orthopedic implanted alloy MP35N and resulting effects on fatigue

    NASA Technical Reports Server (NTRS)

    Wintucky, E. G.; Christopher, M.; Bahnuik, E.; Wang, S.

    1981-01-01

    The effects of two types of argon ion sputter etched surface structures on the tensile stress fatigue properties of orthopedic implant alloy MP35N were investigated. One surface structure was a natural texture resulting from direct bombardment by 1 keV argon ions. The other structure was a pattern of square holes milled into the surface by a 1 keV argon ion beam through a Ni screen mask. The etched surfaces were subjected to tensile stress only in fatigue tests designed to simulate the cyclic load conditions experienced by the stems of artificial hip joint implants. Both types of sputter etched surface structures were found to reduce the fatigue strength below that of smooth surface MP35N.

  13. Au3+ ion implantation on FTO coated glasses: Effect on structural, electrical, optical and phonon properties

    NASA Astrophysics Data System (ADS)

    Sahu, Bindu; Dey, Ranajit; Bajpai, P. K.

    2017-06-01

    Effects of 11.00 MeV Au3+ ions implanted in FTO coated (thickness ≈300 nm) silicate glasses on structural, electrical optical and phonon behavior have been explored. It has been observed that metal clustering near the surface and sub-surface region below glass-FTO interface changes electrical and optical properties significantly. Ion implantation does not affect the crystalline structure of the coated films; however, the unit cell volume decreases with increase in fluence and the tetragonal distortion (c/a ratio) also decreases systematically in the implanted samples. The sheet resistivity of the films increases from 11 × 10-5 ohm-cm (in pristine) to 7.5 × 10-4 ohm-cm for highest ion beam fluence ≈1015 ions/cm2. The optical absorption decreases with increasing fluence whereas, the optical transmittance as well as reflectance increases with increasing fluence. The Raman spectra are observed at ∼530 cm-1 and ∼1103 cm-1 in pristine sample. The broad band at 530 cm-1 shifts towards higher wave number in the irradiated samples. This may be correlated with increased disorder and strain relaxation in the samples as a result of ion beam irradiation.

  14. 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.

  15. Effect of ion implantation on subsequent erosion and wear behavior of solids

    SciTech Connect

    McHargue, C.J.

    1985-01-01

    The removal of material from a solid surface by mechanical forces is influenced by material properties (hardness, fracture toughness, yield strength, surface free energy) as well as system parameters (force, velocity of loading, environment). Ion implantation can modify many of the material properties either by directly affecting the deformation characteristics or indirectly by affecting the chemical or phase composition at the surface. The various forms of wear and erosion are analyzed to determine the material and system parameters which control material removal. The effects of implantation on these critical parameters are noted and examples of changes in surface topography under various test conditions are discussed. 18 figs.

  16. 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.

  17. 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.

  18. Effect of low-energy hydrogen ion implantation on dendritic web silicon solar cells

    NASA Technical Reports Server (NTRS)

    Rohatgi, A.; Meier, D. L.; Rai-Choudhury, P.; Fonash, S. J.; Singh, R.

    1986-01-01

    The effect of a low-energy (0.4 keV), short-time (2-min), heavy-dose (10 to the 18th/sq cm) hydrogen ion implant on dendritic web silicon solar cells and material was investigated. Such an implant was observed to improve the cell open-circuit voltage and short-circuit current appreciably for a number of cells. In spite of the low implant energy, measurements of internal quantum efficiency indicate that it is the base of the cell, rather than the emitter, which benefits from the hydrogen implant. This is supported by the observation that the measured minority-carrier diffusion length in the base did not change when the emitter was removed. In some cases, a threefold increase of the base diffusion length was observed after implantation. The effects of the hydrogen implantation were not changed by a thermal stress test at 250 C for 111 h in nitrogen. It is speculated that hydrogen enters the bulk by traveling along dislocations, as proposed recently for edge-defined film-fed growth silicon ribbon.

  19. The effect of germanium ion implantation dose on the amorphization and recrystallization of polycrystalline silicon films

    NASA Astrophysics Data System (ADS)

    Komem, Y.; Hall, I. W.

    1981-11-01

    Polycrystalline Si films have been amorphized by implantation with 130-keV Ge ions and subsequently recrystallized by conventional heat treatment. It is found that, after amorphization with a low ion dose, recrystallization produces a structure which is morphologically similar to the original film. By contrast, after high Ge dose implantation, recrystallization proceeds dendritically. An initial rationale for this behavior is proposed in terms of the lattice disorder introduced by ion implantation.

  20. The effects of ion implantation on the beaks of orthodontic pliers

    SciTech Connect

    Mizrahi, E.; Cleaton-Jones, P.E.; Luyckz, S.; Fatti, L.P. )

    1991-06-01

    The surface of stainless steel may be hardened by bombarding the material with a stream of nitrogen ions generated by a nuclear accelerator. In the present study this technique was used to determine the hardening effect of ion implantation on the beaks of stainless steel orthodontic pliers. Ten orthodontic pliers (Dentarum 003 094) were divided into two equal groups, designated control and experimental. The beaks of the experimental pliers were subjected to ion implantation, after which the tips of the beaks of all the pliers were stressed in an apparatus attached to an Instron testing machine. A cyclical load of 500 N was applied to the handles of the pliers, while a 0.9 mm (0.036 inch) round, stainless steel wire was held between the tips of the beaks. The effect of the stress was assessed by measurement with a traveling microscope of the gap produced between the tips of the beaks. Measurements were taken before loading and after 20, 40, 60, and 80 cycles. Statistical analysis of variance and the two-sample t tests indicated that there was a significant increase in the size of the gap as the pliers were stressed from 0 to 80 cycles (p less than 0.001). Furthermore, the mean gap was significantly greater in the control group than in the experimental group (p less than 0.001). This study suggests that ion implantation increases the hardness of the tips of the beaks of orthodontic pliers.

  1. Gate dielectric ion implantation to modulate the threshold voltage of In2O3 nanowire field effect transistors

    NASA Astrophysics Data System (ADS)

    Yu, Yang; Li, Wenqing; Wu, Pengcheng; Jiang, Changzhong; Xiao, Xiangheng

    2016-11-01

    In semiconductor technology, In2O3 nanowire field effect transistor (FET) can serve as an important building block due to its admirable electrical switching properties. However, the relatively too large threshold voltages and threshold voltage fluctuations of the devices may hinder their extensive applications. In this report, N+ ion implantation of gate dielectric was conducted to modulate the threshold voltage of In2O3 nanowire FET. Electrical measurements reveal that the threshold voltage can be reduced to as low as -2.0 V from the initial -23.2 V after ion implantation. This can be attributed to the effects of implantation induced electron traps. Moreover, it is found that the stability of threshold voltage can be improved by ion implantation. This simple and convenient method indicates that gate dielectric ion implantation may be a potential way to realize the low voltage operation and uniform In2O3 nanowire FETs.

  2. 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.

  3. Effects of positive ion implantation into antireflection coating of silicon solar cells

    NASA Technical Reports Server (NTRS)

    Middleton, A. E.; Harpster, J. W.; Collis, W. J.; Kim, C. K.

    1971-01-01

    The state of technological development of Si solar cells for highest obtained efficiency and radiation resistance is summarized. The various theoretical analyses of Si solar cells are reviewed. It is shown that factors controlling blue response are carrier diffusion length, surface recombination, impurity concentration profile in surface region, high level of surface impurity concentration (degeneracy), reflection coefficient of oxide, and absorption coefficient of Si. The theory of ion implantation of charge into the oxide antireflection coating is developed and side effects are discussed. The experimental investigations were directed at determining whether the blue response of Si solar cells could be improved by phosphorus ion charges introduced into the oxide antireflection coating.

  4. Effects of Thermal Annealing on the Formation of Buried β-SiC by Ion Implantation

    NASA Astrophysics Data System (ADS)

    Poudel, P. R.; Rout, B.; Diercks, D. R.; Paramo, J. A.; Strzhemechny, Y. M.; McDaniel, F. D.

    2011-09-01

    A systematic study of the formation of buried β-SiC structures by carbon ion implantation into Si followed by high-temperature thermal annealing has been carried out. A high fluence of carbon ions (8 × 1017 atoms/cm2) was implanted at 65 keV energy. Formation of the crystalline β-SiC phase was monitored by Fourier-transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) techniques. The implanted samples were annealed at 900°C and 1100°C to observe the effects of annealing temperature on the formation of crystalline β-SiC. Formation of crystalline β-SiC was clearly observed in the sample annealed at 1100°C in a flowing nitrogen environment for a period of 1 h. Graphitic carbon clusters were observed at the implanted carbon profile peak position by XPS depth profile measurements. Various structural defects such as grain boundaries were also visualized in the annealed sample by high-resolution TEM.

  5. Effect of calcium-ion implantation on the corrosion resistance and biocompatibility of titanium.

    PubMed

    Krupa, D; Baszkiewicz, J; Kozubowski, J A; Barcz, A; Sobczak, J W; Bilińiski, A; Lewandowska-Szumieł, M D; Rajchel, B

    2001-08-01

    This work presents data on the structure and corrosion resistance of titanium after calcium-ion implantation with a dose of 10(17) Ca+/cm2. The ion energy was 25 keV. Transmission electron microscopy was used to investigate the microstructure of the implanted layer. The chemical composition of the surface layer was examined by XPS and SIMS. The corrosion resistance was examined by electrochemical methods in a simulated body fluid (SBF) at a temperature of 37 degrees C. Biocompatibility tests in vitro were performed in a culture of human derived bone cells (HDBC) in direct contact with the materials tested. Both, the viability of the cells determined by an XTT assay and activity of the cells evaluated by alkaline phosphatase activity measurements in contact with implanted and non-implanted titanium samples were detected. The morphology of the cells spread on the surface of the materials examined was also observed. The results confirmed the biocompatibility of both calcium-ion-implanted and non-implanted titanium under the conditions of the experiment. As shown by TEM results, the surface layer formed during calcium-ion implantation was amorphous. The results of electrochemical examinations indicate that calcium-ion implantation increases the corrosion resistance, but only under stationary conditions; during anodic polarization the calcium-ion-implanted samples undergo pitting corrosion. The breakdown potential is high (2.7-3 V).

  6. 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.

  7. Copper and silver ion implantation of aluminium oxide-blasted titanium surfaces: proliferative response of osteoblasts and antibacterial effects.

    PubMed

    Fiedler, Jörg; Kolitsch, Andreas; Kleffner, Bernhard; Henke, Dietmar; Stenger, Steffen; Brenner, Rolf E

    2011-09-01

    Implant infection still represents a major clinical problem in orthopedic surgery. We therefore tested the in vitro biocompatibility and antibacterial effects of copper (Cu)- and silver (Ag)-ion implantation. Discs of a commonly used titanium alloy (Ti6AlV4) with an aluminium oxide-blasted surface were treated by Cu- or Ag-ion implantation with different dosage regimen (ranging from 1e15-17 ions cm(-2) at energies of 2-20 keV). The samples were seeded with primary human osteoblasts and cell attachment and proliferation was analyzed by an MTT-assay. In comparison to the reference titanium alloy there was no difference in the number of attached viable cells after two days. After seven days the number of viable cells was increased for Cu with 1e17 ions cm(-2) at 2 and 5 keV, and for Ag with 1e16 ions cm(-2) at 5 keV while it was reduced for the highest amount of Ag deposition (1e17 ions cm(-2) at 20 keV). Antibacterial effects on S.aureus and E.coli were marginal for the studied dosages of Cu but clearly present for Ag with 1e16 ions cm(-2) at 2 and 5 keV and 1e17 ions cm(-2) at 20 keV. These results indicate that Ag-ion implantation may be a promising methodological approach for antibacterial functionalization of titanium implants.

  8. Magnetic and Mössbauer effect studies of ZnO thin film implanted with iron ions to high fluence

    NASA Astrophysics Data System (ADS)

    Zinnatullin, A. L.; Gumarov, A. I.; Gilmutdinov, I. F.; Valeev, V. F.; Khaibullin, R. I.; Vagizov, F. G.

    2017-01-01

    We present the results of magnetic and Mössbauer effect studies of zinc oxide thin film obtained by RF magnetron sputtering and implanted with 40 keV iron ions to a fluence of 1.5·1017 ion/cm2. As-implanted and post-annealed sample shows ferromagnetic properties at room temperature and consists of paramagnetic and ferromagnetic phases according to Mössbauer spectroscopy.

  9. Biological effects of low energy nitrogen ion implantation on Jatropha curcas L. seed germination

    NASA Astrophysics Data System (ADS)

    Xu, Gang; Wang, Xiao-teng; Gan, Cai-ling; Fang, Yan-qiong; Zhang, Meng

    2012-09-01

    To explore the biological effects of nitrogen ion beam implantation on dry Jatropha curcas seed, a beam of N+ with energy of 25 keV was applied to treat the dry seed at six different doses. N+ beam implantation greatly decreased germination rate and seedling survival rate. The doses within the range of 12 × 1016 to 15 × 1016 ions cm-2 severely damaged the seeds: total antioxidant capacity (TAC), germination rate, seedling survival rate, reduced ascorbate acid (HAsA) and reduced glutathione (GSH) contents, and most of the tested antioxidases activity (i.e. catalase (CAT), ascorbate peroxidase (APX) and superoxide dismutase (SOD)) reached their lowest levels. At a dose of 18 × 1016 ion cm-2, biological repair took place: moderate increases were found in TAC, germination rate, seedling survival rate, HAsA and GSH contents, and some antioxidant enzyme activities (i.e. CAT, APX, SOD and GPX). The dose of 18 × 1016 ions cm-2 may be the optimum dose for use in dry J. curcas seed mutation breeding. CAT, HAsA and GSH contributed to the increase of TAC, but CAT was the most important. POD performed its important role as seed was severely damaged. The main role of the HAsA-GSH cycle appeared to be for regeneration of HAsA.

  10. Mossbauer effect in the ion-implanted iron-carbon alloys

    NASA Technical Reports Server (NTRS)

    Han, K. S.

    1976-01-01

    The concentration dependence of Mossbauer effect in four carbon ion-implanted iron absorbers, which contain carbon as the solute atoms, has been investigated over the range of concentration 0.05 through 1 atomic percent. The specimens were prepared by implanting carbon atoms on each reference iron foil with four different bombarding energies of 250 keV, 160 keV, 140 keV and 80 keV, respectively. Thus, the specimen contains a uniform dosage of carbon atoms which penetrated up to 3,000 A depth of the reference iron. In the measurement of Mossbauer spectra, the backscattering conversion electron counting geometry was used. Typical results of Mossbauer parameters of iron-carbon alloys show that the isomer shift, quadrupole shift, the effective hyperfine splitting of Fe-57, and the intensity ratio exhibit a large variation with the increase of carbon concentration in the environment of iron atoms.

  11. 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.

  12. The lattice expansion, damage effect and propagation loss of KTiOPO4 waveguides formed by ion implantation

    NASA Astrophysics Data System (ADS)

    Wang, Liang-Ling; Cui, Xiao-Jun; Rensberg, Jura; Yin, Jiao-Jian; Creutzburg, Sascha; Ritter, Konrad; Wesch, Werner; Wendler, Elke

    2017-04-01

    We investigated the damage effect on the refractive index as well as the lattice expansion induced by C3+ ion implantation into KTiOPO4 crystals. A KTiOPO4 channel waveguide was formed by area-selective 6.0 MeV C3+ ion implantation at a fluence of 5 × 1013 ions/cm2 using photoresist masking, and planar waveguides were formed by ion implantation with 6.0 MeV C3+ ions at fluences from 8 × 1012 ions/cm2 to 6 × 1014 ions/cm2. The propagation loss of the KTiOPO4 planar waveguides at 633 nm fabricated at fluences of 2 × 1013 ions/cm2 and 5 × 1013 ions/cm2 after annealing is as low as 0.38 and 0.54 dB/cm, respectively. Prism coupling and refractive index profile reconstruction using the reflectivity calculation method were used to investigate the anisotropy of the refractive indices in the KTiOPO4 waveguides region before and after annealing. The lattice expansion induced by ion implantation was investigated by combining X-ray rocking curves with atomic force microscopy. Rutherford backscattering spectrometry and channeling was applied for damage analysis, and the relationship between effective refractive index and relative defect concentration was studied.

  13. Synergistic effect of nanotopography and bioactive ions on peri-implant bone response

    PubMed Central

    Su, Yingmin; Komasa, Satoshi; Li, Peiqi; Nishizaki, Mariko; Chen, Luyuan; Terada, Chisato; Yoshimine, Shigeki; Nishizaki, Hiroshi; Okazaki, Joji

    2017-01-01

    Both bioactive ion chemistry and nanoscale surface modifications are beneficial for enhanced osseointegration of endosseous implants. In this study, a facile synthesis approach to the incorporation of bioactive Ca2+ ions into the interlayers of nanoporous structures (Ca-nano) formed on a Ti6Al4V alloy surface was developed by sequential chemical and heat treatments. Samples with a machined surface and an Na+ ion-incorporated nanoporous surface (Na-nano) fabricated by concentrated alkali and heat treatment were used in parallel for comparison. The bone response was investigated by microcomputed tomography assessment, sequential fluorescent labeling analysis, and histological and histomorphometric evaluation after 8 weeks of implantation in rat femurs. No significant differences were found in the nanotopography, surface roughness, or crystalline properties of the Ca-nano and Na-nano surfaces. Bone–implant contact was better in the Ca-nano and Na-nano implants than in the machined implant. The Ca-nano implant was superior to the Na-nano implant in terms of enhancing the volume of new bone formation. The bone formation activity consistently increased for the Ca-nano implant but ceased for the Na-nano implant in the late healing stage. These results suggest that Ca-nano implants have promising potential for application in dentistry and orthopedics. PMID:28184162

  14. 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

  15. 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.

  16. 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.

  17. Study of the effects of focused high-energy boron ion implantation in diamond

    NASA Astrophysics Data System (ADS)

    Ynsa, M. D.; Agulló-Rueda, F.; Gordillo, N.; Maira, A.; Moreno-Cerrada, D.; Ramos, M. A.

    2017-08-01

    Boron-doped diamond is a material with a great technological and industrial interest because of its exceptional chemical, physical and structural properties. At modest boron concentrations, insulating diamond becomes a p-type semiconductor and at higher concentrations a superconducting metal at low temperature. The most conventional preparation method used so far, has been the homogeneous incorporation of boron doping during the diamond synthesis carried out either with high-pressure sintering of crystals or by chemical vapour deposition (CVD) of films. With these methods, high boron concentration can be included without distorting significantly the diamond crystalline lattice. However, it is complicated to manufacture boron-doped microstructures. A promising alternative to produce such microstructures could be the implantation of focused high-energy boron ions, although boron fluences are limited by the damage produced in diamond. In this work, the effect of focused high-energy boron ion implantation in single crystals of diamond is studied under different irradiation fluences and conditions. Micro-Raman spectra of the sample were measured before and after annealing at 1000 °C as a function of irradiation fluence, for both superficial and buried boron implantation, to assess the changes in the diamond lattice by the creation of vacancies and defects and their degree of recovery after annealing.

  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. Effects of low-energy argon ion implantation on the dynamic organization of the actin cytoskeleton during maize pollen germination.

    PubMed

    Deng, F; Zhu, S W; Wu, L J; Cheng, B J

    2010-04-27

    The relationship between pollen germination and the dynamic organization of the actin cytoskeleton during pollen germination is a central theme in plant reproductive biology research. Maize (Zea mays) pollen grains were implanted with 30 keV argon ion (Ar(+)) beams at doses ranging from 0.78 x 10(15) to 13 x 10(15) ions/cm(2). The effects of low-energy ion implantation on pollen germination viability and the dynamic organization of the actin cytoskeleton during pollen germination were studied using confocal laser scanning microscopy. Maize pollen germination rate increased remarkably with Ar(+) dose, in the range from 3.9 x 10(15) to 6.5 x 10(15) ions/cm(2); the germination rate peaked at an Ar(+) dose of 5.2 x 10(15) ions/cm(2). When the implantation dose exceeded 7.8 x 10(15) ions/cm(2), the rate of pollen germination decreased sharply. The actin filaments assembled in pollen grains implanted with 5.2 x 10(15) ions/cm(2) Ar(+) much earlier than in controls. The actin filaments organized as longer parallel bundles and extended into the emerging pollen tube in treated pollen grains, while they formed random and loose fine bundles and were gathered at the pollen aperture in the control. The reorganization of actin cytoskeleton in the pollen implanted with 9.1 x 10(15) ions/cm(2) Ar(+) was slower than in controls. There was a positive correlation between pollen germination and the dynamic organization of the actin cytoskeleton during pollen germination. Ion implantation into pollen did not cause changes in the polarization of actin filaments and organelle dynamics in the pollen tubes. The effects of Ar(+) implantation on pollen germination could be mediated by changes in the polymerization and rearrangement of actin polymers.

  20. Effect of ion implantation on the tribology of metal-on-metal hip prostheses.

    PubMed

    Bowsher, John G; Hussain, Azad; Williams, Paul; Nevelos, Jim; Shelton, Julia C

    2004-12-01

    Nitrogen ion implantation (which considerably hardens the surface of the bearing) may represent one possible method of reducing the wear of metal-on-metal (MOM) hip bearings. Currently there are no ion-implanted MOM bearings used clinically. Therefore a physiological hip simulator test was undertaken using standard test conditions, and the results compared to previous studies using the same methods. N2-ion implantation of high carbon cast Co-Cr-Mo-on-Co-Cr-Mo hip prostheses increased wear by 2-fold during the aggressive running-in phase compared to untreated bearing surfaces, plus showing no wear reductions during steady-state conditions. Although 2 specimens were considered in the current study, it would appear that ion implantation has no clinical benefit for MOM.

  1. 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.

  2. 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.

  3. Effect of argon ion implantation on the electrical and dielectric properties of CR-39

    SciTech Connect

    Chawla, Mahak Shekhawat, Nidhi; Goyal, Meetika; Gupta, Divya; Sharma, Annu; Aggarwal, Sanjeev

    2016-05-23

    The objective of the present work is to study the effect of 130 keV Ar{sup +} ions on the electrical and dielectric properties of CR-39 samples at various doses 5×10{sup 14}, 1×10{sup 15} and 1×10{sup 16} Ar{sup +} cm{sup −2}. Current-Voltage (I-V characteristics) measurements have been used to study the electrical properties of virgin and Ar{sup +} implanted CR-39 specimens. The current has been found to be increased with increasing voltage as well as with increasing ion dose. The dielectric spectroscopy of these specimens has been done in the frequency range of 100 kHz-100 MHz. The dielectric constant has been found to be decreasing whereas dielectric loss factor increases with increasing ion fluence. These kind of behavior observed in the implanted specimens indicate towards the formation of carbonaceous clusters due to the cross linking, chemical bond cleavage, formation of free radicals. The changes observed in the dielectric behavior have been further correlated with the structural changes observed through I-V characteristics.

  4. Effect of argon ion implantation on the electrical and dielectric properties of CR-39

    NASA Astrophysics Data System (ADS)

    Chawla, Mahak; Shekhawat, Nidhi; Goyal, Meetika; Gupta, Divya; Sharma, Annu; Aggarwal, Sanjeev

    2016-05-01

    The objective of the present work is to study the effect of 130 keV Ar+ ions on the electrical and dielectric properties of CR-39 samples at various doses 5×1014, 1×1015 and 1×1016 Ar+ cm-2. Current-Voltage (I-V characteristics) measurements have been used to study the electrical properties of virgin and Ar+ implanted CR-39 specimens. The current has been found to be increased with increasing voltage as well as with increasing ion dose. The dielectric spectroscopy of these specimens has been done in the frequency range of 100 kHz-100 MHz. The dielectric constant has been found to be decreasing whereas dielectric loss factor increases with increasing ion fluence. These kind of behavior observed in the implanted specimens indicate towards the formation of carbonaceous clusters due to the cross linking, chemical bond cleavage, formation of free radicals. The changes observed in the dielectric behavior have been further correlated with the structural changes observed through I-V characteristics.

  5. 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.

  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. The effect of ions on the magnetic moment of vacancy for ion-implanted 4H-SiC

    NASA Astrophysics Data System (ADS)

    Peng, B.; Zhang, Y. M.; Dong, L. P.; Wang, Y. T.; Jia, R. X.

    2017-04-01

    The structural properties and the spin states of vacancies in ion implanted silicon carbide samples are analyzed by experimental measurements along with first-principles calculations. Different types and dosages of ions (N+, O+, and B+) were implanted in the 4H-silicon carbide single crystal. The Raman spectra, positron annihilation spectroscopy, and magnetization-magnetic field curves of the implanted samples were measured. The fitting results of magnetization-magnetic field curves reveal that samples implanted with 1 × 1016 cm-2 N+ and O+ ions generate paramagnetic centers with various spin states of J = 1 and J = 0.7, respectively. While for other implanted specimens, the spin states of the paramagnetic centers remain unchanged compared with the pristine sample. According to the positron annihilation spectroscopy and first-principles calculations, the change in spin states originates from the silicon vacancy carrying a magnetic moment of 3.0 μB in the high dosage N-implanted system and 2.0 μB in the O-doped system. In addition, the ratio of the concentration of implanted N ions and silicon vacancies will affect the magnetic moment of VSi. The formation of carbon vacancy which does not carry a local magnetic moment in B-implanted SiC can explain the invariability in the spin states of the paramagnetic centers. These results will help to understand the magnetic moments of vacancies in ion implanted 4H-SiC and provide a possible routine to induce vacancies with high spin states in SiC for the application in quantum technologies and spintronics.

  8. Effects of sequential tungsten and helium ion implantation on nano-indentation hardness of tungsten

    SciTech Connect

    Armstrong, D. E. J.; Edmondson, P. D.; Roberts, S. G.

    2013-06-24

    To simulate neutron and helium damage in a fusion reactor first wall sequential self-ion implantation up to 13 dpa followed by helium-ion implantation up to 3000 appm was performed to produce damaged layers of {approx}2 {mu}m depth in pure tungsten. The hardness of these layers was measured using nanoindentation and was studied using transmission electron microscopy. Substantial hardness increases were seen in helium implanted regions, with smaller hardness increases in regions which had already been self-ion implanted, thus, containing pre-existing dislocation loops. This suggests that, for the same helium content, helium trapped in distributed vacancies gives stronger hardening than helium trapped in vacancies condensed into dislocation loops.

  9. Effects of sequential tungsten and helium ion implantation on nano-indentation hardness of tungsten

    NASA Astrophysics Data System (ADS)

    Armstrong, D. E. J.; Edmondson, P. D.; Roberts, S. G.

    2013-06-01

    To simulate neutron and helium damage in a fusion reactor first wall sequential self-ion implantation up to 13 dpa followed by helium-ion implantation up to 3000 appm was performed to produce damaged layers of ˜2 μm depth in pure tungsten. The hardness of these layers was measured using nanoindentation and was studied using transmission electron microscopy. Substantial hardness increases were seen in helium implanted regions, with smaller hardness increases in regions which had already been self-ion implanted, thus, containing pre-existing dislocation loops. This suggests that, for the same helium content, helium trapped in distributed vacancies gives stronger hardening than helium trapped in vacancies condensed into dislocation loops.

  10. 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.

  11. 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.

  12. The effect of nitrogen ion implantation on the corrosion resistance and microstructure of tantalum-coated stainless steel

    NASA Astrophysics Data System (ADS)

    Eshghi, S.; Hanteh Zadeh, M.; Yari, M.; Jafari-Khamse, E.

    2014-06-01

    In this work, the effects of nitrogen ion implantation on the corrosion resistance and microstructure of DC magnetron sputtered tantalum-coated stainless steel were investigated. The nitrogen fluence was varied between 3-10 × 1017 ions/cm2 while the beam energy was kept constant at 30 keV. The effects of ion implantation were characterized by X-ray diffraction pattern, atomic force microscopy, and potentiodynamic corrosion test in a 0.5 MH2SO4 solution. The atomic force microscopy micrographs were quantitatively and statistically analyzed by computing the multifractal spectrum of the atomic force microscopy images. The results showed that the fluence variation strongly affected the surface roughness and formation of TaN and Ta2N phases. Increasing the nitrogen fluence up to 10 × 1017 ions/cm2 increased surface roughness. The highest corrosion resistance was obtained at 7 × 1017 ions/cm2 nitrogen fluence.

  13. Effects of Mo ion implantation on rolling contact fatigue behavior of carbon steel

    SciTech Connect

    Yang, D.; Zhou, J.

    1996-11-01

    Rolling Contact Fatigue (RCF) is one of the most serious material surface damage problems encountered by many critical components, especially in ball-bearing applications. RCF is sensitive to the material strength, hardness, surface morphology, microstructure and stress status, which may be dramatically changed by surface modifications. In present work, the surface modification of molybdenum ion implantation into quenched carbon steel was employed, and RCF tests on the implanted specimens, as well as the unimplanted, were performed. It was found out that carbon steel specimens, with and without ion implantation, have the same fatigue damage characteristics. They both have circular and fan-like pits on the fatigue failed surfaces, with many spherical debris existing in the fan-like pits. However, molybdenum ion implantation reduced the rolling contact fatigue life of quenched carbon steel. The possible reasons are the following: the ion beam current is too large, which causes the specimen to undergo the annealing process and soften during the implantation process; the incident angles of ions are different for different spots of curve specimen surface, which causes the uneven distribution of residual stress. These will promote the crack initiation and propagation.

  14. Effects of nitrogen ion implantation time on tungsten films deposited by DC magnetron sputtering on AISI 410 martensitic stainless steel

    SciTech Connect

    Malau, Viktor Ilman, Mochammad Noer Iswanto, Priyo Tri Jatisukamto, Gaguk

    2016-03-29

    Nitrogen ion implantation time on tungsten thin film deposited on surface of AISI 410 steel has been performed. Tungsten thin film produced by dc magnetron sputtering method was deposited on AISI 410 martensitic stainless steel substrates, and then the nitrogen ions were implanted on tungsten thin film. The objective of this research is to investigate the effects of implantation deposition time on surface roughness, microhardness, specific wear and corrosion rate of nitrogen implanted on tungsten film. Magnetron sputtering process was performed by using plasma gas of argon (Ar) to bombardier tungsten target (W) in a vacuum chamber with a pressure of 7.6 x 10{sup −2} torr, a voltage of 300 V, a sputter current of 80 mA for sputtered time of 10 minutes. Nitrogen implantation on tungsten film was done with an initial pressure of 3x10{sup −6} mbar, a fluence of 2 x 10{sup 17} ions/cm{sup 2}, an energy of 100 keV and implantation deposition times of 0, 20, 30 and 40 minutes. The surface roughness, microhardness, specific wear and corrosion rate of the films were evaluated by surfcorder test, Vickers microhardness test, wear test and potentiostat (galvanostat) test respectively. The results show that the nitrogen ions implanted deposition time on tungsten film can modify the surface roughness, microhardness, specific wear and corrosion rate. The minimum surface roughness, specific wear and corrosion rate can be obtained for implantation time of 20 minutes and the maximum microhardness of the film is 329 VHN (Vickers Hardness Number) for implantation time of 30 minutes. The specific wear and corrosion rate of the film depend directly on the surface roughness.

  15. Effects of nitrogen ion implantation time on tungsten films deposited by DC magnetron sputtering on AISI 410 martensitic stainless steel

    NASA Astrophysics Data System (ADS)

    Malau, Viktor; Ilman, Mochammad Noer; Iswanto, Priyo Tri; Jatisukamto, Gaguk

    2016-03-01

    Nitrogen ion implantation time on tungsten thin film deposited on surface of AISI 410 steel has been performed. Tungsten thin film produced by dc magnetron sputtering method was deposited on AISI 410 martensitic stainless steel substrates, and then the nitrogen ions were implanted on tungsten thin film. The objective of this research is to investigate the effects of implantation deposition time on surface roughness, microhardness, specific wear and corrosion rate of nitrogen implanted on tungsten film. Magnetron sputtering process was performed by using plasma gas of argon (Ar) to bombardier tungsten target (W) in a vacuum chamber with a pressure of 7.6 x 10-2 torr, a voltage of 300 V, a sputter current of 80 mA for sputtered time of 10 minutes. Nitrogen implantation on tungsten film was done with an initial pressure of 3x10-6 mbar, a fluence of 2 x 1017 ions/cm2, an energy of 100 keV and implantation deposition times of 0, 20, 30 and 40 minutes. The surface roughness, microhardness, specific wear and corrosion rate of the films were evaluated by surfcorder test, Vickers microhardness test, wear test and potentiostat (galvanostat) test respectively. The results show that the nitrogen ions implanted deposition time on tungsten film can modify the surface roughness, microhardness, specific wear and corrosion rate. The minimum surface roughness, specific wear and corrosion rate can be obtained for implantation time of 20 minutes and the maximum microhardness of the film is 329 VHN (Vickers Hardness Number) for implantation time of 30 minutes. The specific wear and corrosion rate of the film depend directly on the surface roughness.

  16. A Study of Temperature Effect on Ta+N Ion-Implanted Hardalloy

    NASA Astrophysics Data System (ADS)

    Zhao, Qing; Zhao, Feng; Tong, Hong-hui; Geng, Man; Zheng, Yong-zhen

    2001-08-01

    Hard alloy were implanted with a dual-ion of nitrogen and tantalum at temperature of 100 °C and 400 °C at a dose of 8×1017 ions cm-2. Auger electron spectroscopy (AES) was used to determine the nitrogen and tantalum concentration profiles. Microhardness measurements were performed to evaluate the improvements in surface property. The thickness of implanted layers increased by about an order of magnitude when the temperature was elevated from 100 °C to 400 °C. A higher surface hardness was also obtained in the higher temperature implantation. Scanning electron microscopy (SEM) image showed distinct microstructural changes, and x-ray diffraction (XRD) analysis showed the presence of nitrides of tantalum and tungsten on the surface implanted.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. Energetic metallic ion implantation in polymers via cost-effective laser-driven ion source

    NASA Astrophysics Data System (ADS)

    Tahir, Muhammad Bilal; Rafique, M. Shahid; Ahmed, Rabia; Rafique, M.; Iqbal, Tahir; Hasan, Ali

    2017-07-01

    This research work reports the ions emission from the plasma generated by Nd:YAG laser having wavelength 1.064 μm, power 1.1 MW, pulse energy 10 mJ and intensity 1011 W/cm2 irradiated at 70° with respect to the target normal to the ions. These ions were accelerated through a home-made extraction assembly by means of a high voltage DC power supply. The energy of these ions were measured using Thomson parabola technique which utilizes Solid State Nuclear Track Detector (CR-39) and confirmed by Faraday cup as well that exploits a well-known technique known as time of flight. Interestingly, a significant increase in energy (from 490 to 730 keV) was observed with a discrete increase in acceleration potential from 0 to 18 kV. Polyethylene terephthalate (PET) and polypropylene were exposed to this recently developed ion source facility, to authenticate the reliability of this facility. The surface of the polymer is affected when energy of the irradiated ion is increased, which is evident from the optical micrographs. An increase in electrical conductivity was also observed with the increase in ion energy.

  4. Effects of cesium ion-implantation on mechanical and electrical properties of organosilicate low-k films

    SciTech Connect

    Li, W.; Pei, D.; Guo, X.; Cheng, M. K.; Lee, S.; Shohet, J. L.; Lin, Q.; King, S. W.

    2016-05-16

    The effects of cesium (Cs) ion-implantation on uncured plasma-enhanced chemical-vapor-deposited organosilicate low dielectric constant (low-k) (SiCOH) films have been investigated and compared with an ultraviolet (UV) cured film. The mechanical properties, including the elastic modulus and hardness, of the SiCOH low-k films are improved by up to 30% with Cs implantation, and further up to 52% after annealing at 400 °C in a N{sub 2} ambient for 1 h. These improvements are either comparable to or better than the effects of UV-curing. They are attributed to an enhancement of the Si-O-Si network structure. The k-value of the SiCOH films increased slightly after Cs implantation, and increased further after annealing. These increases are attributed to two carbon-loss mechanisms, i.e., the carbon loss due to Si-CH{sub 3} bond breakage from implanted Cs ions, and the carbon loss due to oxidation during the annealing. The time-zero dielectric breakdown strength was improved after the Cs implantation and the annealing, and was better than the UV-cured sample. These results indicate that Cs ion implantation could be a supplement to or a substitution for the currently used UV curing method for processing SiCOH low-k films.

  5. 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.

  6. The effect of platform switching on the levels of metal ion release from different implant-abutment couples.

    PubMed

    Alrabeah, Ghada O; Knowles, Jonathan C; Petridis, Haralampos

    2016-06-30

    The improved peri-implant bone response demonstrated by platform switching may be the result of reduced amounts of metal ions released to the surrounding tissues. The aim of this study was to compare the levels of metal ions released from platform-matched and platform-switched implant-abutment couples as a result of accelerated corrosion. Thirty-six titanium alloy (Ti-6Al-4V) and cobalt-chrome alloy abutments were coupled with titanium cylinders forming either platform-switched or platform-matched groups (n=6). In addition, 18 unconnected samples served as controls. The specimens were subjected to accelerated corrosion by static immersion in 1% lactic acid for 1 week. The amount of metal ions ion of each test tube was measured using inductively coupled plasma mass spectrometry. Scanning electron microscope (SEM) images and energy dispersive spectroscopy X-ray analyses were performed pre- and post-immersion to assess corrosion at the interface. The platform-matched groups demonstrated higher ion release for vanadium, aluminium, cobalt, chrome, and molybdenum compared with the platform-switched groups (P<0.05). Titanium was the highest element to be released regardless of abutment size or connection (P<0.05). SEM images showed pitting corrosion prominent on the outer borders of the implant and abutment platform surfaces. In conclusion, implant-abutment couples underwent an active corrosion process resulting in metal ions release into the surrounding environment. The highest amount of metal ions released was recorded for the platform-matched groups, suggesting that platform-switching concept has a positive effect in reducing the levels of metal ion release from the implant-abutment couples.

  7. Nonlinear effects in defect production by atomic and molecular ion implantation

    SciTech Connect

    David, C. Dholakia, Manan; Chandra, Sharat; Nair, K. G. M.; Panigrahi, B. K.; Amirthapandian, S.; Amarendra, G.; Varghese Anto, C.; Santhana Raman, P.; Kennedy, John

    2015-01-07

    This report deals with studies concerning vacancy related defects created in silicon due to implantation of 200 keV per atom aluminium and its molecular ions up to a plurality of 4. The depth profiles of vacancy defects in samples in their as implanted condition are carried out by Doppler broadening spectroscopy using low energy positron beams. In contrast to studies in the literature reporting a progressive increase in damage with plurality, implantation of aluminium atomic and molecular ions up to Al{sub 3}, resulted in production of similar concentration of vacancy defects. However, a drastic increase in vacancy defects is observed due to Al{sub 4} implantation. The observed behavioural trend with respect to plurality has even translated to the number of vacancies locked in vacancy clusters, as determined through gold labelling experiments. The impact of aluminium atomic and molecular ions simulated using MD showed a monotonic increase in production of vacancy defects for cluster sizes up to 4. The trend in damage production with plurality has been explained on the basis of a defect evolution scheme in which for medium defect concentrations, there is a saturation of the as-implanted damage and an increase for higher defect concentrations.

  8. Effect of double ion implantation and irradiation by Ar and He ions on nano-indentation hardness of metallic alloys

    NASA Astrophysics Data System (ADS)

    Dayal, P.; Bhattacharyya, D.; Mook, W. M.; Fu, E. G.; Wang, Y.-Q.; Carr, D. G.; Anderoglu, O.; Mara, N. A.; Misra, A.; Harrison, R. P.; Edwards, L.

    2013-07-01

    In this study, the authors have investigated the combined effect of a double layer of implantation on four different metallic alloys, ODS steel MA957, Zircaloy-4, Ti-6Al-4V titanium alloy and stainless steel 316, by ions of two different species - He and Ar - on the hardening of the surface as measured by nano-indentation. The data was collected for a large number of indentations using the Continuous Stiffness Method or "CSM" mode, applying the indents on the implanted surface. Careful analysis of the data in the present investigations show that the relative hardening due to individual implantation layers can be used to obtain an estimate of the relative hardening effect of a combination of two separate implanted layers of two different species. This combined hardness was found to lie between the square root of the sum of the squares of individual hardening effects, (ΔHA2 + ΔHB2)0.5 as the lower limit and the sum of the individual hardening effects, (ΔHA + ΔHB) as the upper limit, within errors, for all depths measured. The hardening due to irradiation by different species of ions was calculated by subtracting the average hardness vs. depth curve of the un-irradiated or "virgin" material from that of the irradiated material. The combined hardening of the irradiated samples due to Ar and He irradiation was found to be described well by an approximate upper bound given by the simple linear sum of the individual hardening (L) and a lower bound given by the square root of the sum of the squares (R) of the individual hardening effects due to Ar and He irradiation along the full depth of the indentation. The peak of the combined hardness of Ar and He irradiated material appears at the depth predicted by both the R and the L curves, in all samples. The combined hardness increase due to Ar and He irradiation lies near the upper limit (L curve) for the ODS steel MA957, somewhere in between L and R curves for Zircaloy-4, and near the R curve for the stainless steel 316

  9. Effect of fluorine ion implantation on the microstructure and microhardness of AISI 440C stainless steel

    NASA Astrophysics Data System (ADS)

    Hanamoto, K.; Sasaki, M.; Miyashita, T.; Kido, Y.; Nakayama, Y.; Kawamoto, Y.; Fujiwara, M.; Kaigawa, R.

    1997-07-01

    AISI 440C stainless steel along with pure iron and chromium have been implanted with 30 keV fluorine ions at doses from 5 × 10 16 to 6 × 10 17 ions/cm 2 and surface hardnesses of the 440C steel have been examined. Implanted regions inside the specimens were studied by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The results of XPS and XRD measurements indicate the formation of FeF 2 and suggest small grains of CrF 2 and non-stoichiometric chromium fluorides in 440C steel. It may be concluded that an increase of the surface hardness in fluorine implanted 440C steel is related to precipitation of metal fluorides and surface oxidation.

  10. Optical properties of planar waveguides on ZnWO₄ formed by carbon and helium ion implantation and effects of annealing.

    PubMed

    Zhao, Jin-Hua; Liu, Tao; Guo, Sha-Sha; Guan, Jing; Wang, Xue-Lin

    2010-08-30

    We report on the optical properties of ZnWO(4) planar waveguides created by ion implantation, and the effect annealing has on these structures. Planar optical waveguides in ZnWO(4) crystals are fabricated by 5.0 MeV carbon ion implantation with a fluence of 1 × 10(15) ions/cm(2) or 500 keV helium ion implantation with the a fluence of 1 × 10(16) ions/cm(2). The thermal stability was investigated by 60 minute annealing cycles at different temperatures ranging from 260°C to 550°C in air. The guided modes were measured by a model 2010 prism coupler at wavelengths of 633 nm and 1539 nm. The reflectivity calculation method (RCM) was applied to simulate the refractive index profile in these waveguides. The near-field light intensity profiles were measured using the end-face coupling method. The absorption spectra show that the implantation processes have almost no influence on the visible band absorption.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Ion implantation effects on surface-mechanical properties of metals and polymers

    SciTech Connect

    Rao, G.R.

    1993-04-01

    Fatigue of 8 complex alloys based on Fe-13Cr-15Ni-2Mo-2Mn-0.2Ti-0.8Si- 0.06C, and single-crystal Fe-15Cr-15Ni, implanted with 400-keV B{sup +} and 550-keV N{sup +} (total dose 2.3{times}10{sup 16} ions/cm{sup 2}) was examined. 600 C creep was also examined. The dual implantation increased hardness but decreased fatigue life of the 8 complex alloys. An optimum strengthening level and a shift to grain boundary cracking were determined. The single crystals also showed reduced fatigue life after implantation. High temperature creep of E1 and B1 alloys were improved by the dual implantation. Four polymers (PE, polypropylene, polystyrene, polyethersulfone) were implanted with 200keV B{sup +} to 3 different doses. PS was also implanted with both B{sup +} and Ar{sup +}. Near-surface hardness and tribological properties were measured. The hardness increased with dose and energy; wear also improved, with an optimum dose. (DLC)

  16. Ion implantation effects on surface-mechanical properties of metals and polymers

    SciTech Connect

    Rao, G.R.

    1993-04-01

    Fatigue of 8 complex alloys based on Fe-13Cr-15Ni-2Mo-2Mn-0.2Ti-0.8Si- 0.06C, and single-crystal Fe-15Cr-15Ni, implanted with 400-keV B[sup +] and 550-keV N[sup +] (total dose 2.3[times]10[sup 16] ions/cm[sup 2]) was examined. 600 C creep was also examined. The dual implantation increased hardness but decreased fatigue life of the 8 complex alloys. An optimum strengthening level and a shift to grain boundary cracking were determined. The single crystals also showed reduced fatigue life after implantation. High temperature creep of E1 and B1 alloys were improved by the dual implantation. Four polymers (PE, polypropylene, polystyrene, polyethersulfone) were implanted with 200keV B[sup +] to 3 different doses. PS was also implanted with both B[sup +] and Ar[sup +]. Near-surface hardness and tribological properties were measured. The hardness increased with dose and energy; wear also improved, with an optimum dose. (DLC)

  17. 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.

  18. Effects of ion-implantation damage on two-dimensional boron diffusion in silicon

    SciTech Connect

    Marchiando, J.F.; Albers, J.

    1987-02-15

    Model two-dimensional distributions of implanted boron and implantation-induced displacement damage near a mask edge are used to calculate the two-dimensional redistribution of boron resulting from a typical short-time anneal. The damage is removed during annealing by releasing vacancies which enhance the diffusion of boron. The effect is that boron preferentially redistributes further into the bulk. Such considerations become increasingly important as metal-oxide-semiconductor field-effect transistors become smaller.

  19. Effects of fluoride-ion-implanted titanium surface on the cytocompatibility in vitro and osseointegatation in vivo for dental implant applications.

    PubMed

    Wang, Xue-jin; Liu, Hui-ying; Ren, Xiang; Sun, Hui-yan; Zhu, Li-ying; Ying, Xiao-xia; Hu, Shu-hai; Qiu, Ze-wen; Wang, Lang-ping; Wang, Xiao-feng; Ma, Guo-wu

    2015-12-01

    As an attractive technique for the improvement of biomaterials, Plasma immersion ion implantation (PIII) has been applied to modifying the titanium material for dental implant application. The present study investigated the cytocompatibility and early osseointegration of fluoride-ion-implanted titanium (F-Ti) surface and implants, both characterizing in their composition of titanium oxide and titanium fluoride. The cytocompatibility of F-Ti was evaluated in vitro by using scanning electron microscope, Cell Counting Kit-8 assay, alkaline phosphatase activity assay, and quantitative real-time polymerase chain reaction. The results showed that the F-Ti weakened the effects that Porphyromonas gingivalis exerted on the MG-63 cells in terms of morphology, proliferation, differentiation, and genetic expression when MG-63 cells and Porphyromonas gingivalis were co-cultured on the surface of F-Ti. Meanwhile, the osteogenic activity of F-Ti implants was assessed in vivo via evaluating the histological morphology and estimating histomorphometric parameters. The analysis of toluidine blue staining indicated that the new bone was more mature in subjects with F-Ti group, which exhibited the Haversian system, and the mean bone-implant contact value of F-Ti group was slightly higher than that of cp-Ti group (p>0.05). Fluorescence bands were wider and brighter in the F-Ti group, and the intensity of fluorochromes deposited at the sites of mineralized bone formation was significantly higher for F-Ti surfaces than for cp-Ti surfaces, within the 2nd, 3rd and 4th weeks (p<0.05). An indication is that the fluoride modified titanium can promote cytocompatibility and early osseointegration, thus providing a promising alternative for clinical use.

  20. Amorphization effects on pure titanium using C{sup +}, O{sup +} and Cr{sup +} ion implantation

    SciTech Connect

    Athanasiou, N.S.; Lanza, F.; Paracchini, L.; Brossa, F.

    1998-01-20

    In this work, the influence of the amorphization effect of C{sup +}, O{sup +} and Cr{sup +} implantation on the friction and wettability properties of pure titanium (grade 2) has been studied. Doses from 1 {times} 10{sup 17} to 5 {times} 10{sup 17} ions cm{sup {minus}2} at multiple energies of 50 to 190 keV have been used. Additionally, pin-on-disk tribological tests using Ultra-High-Molecular-Weight-Polyethylene (UHMWPE) pins under lubricated conditions and wettability measurements of implanted and unimplanted titanium samples were carried out. The authors found, that the more suitable material for the wettability and hence wear resistance is C{sup +} implanted titanium, because of its higher surface energy than the unimplanted titanium corresponding energy. Friction tests on monoenergetic 180 keV C{sup +} and O{sup +} modified titanium with 1 {times} 10{sup 17} ions cm{sup {minus}2} have showed an essentially reduced friction compared to samples implanted with the same dose but at multiple energies. A reduction of the wettability by about 7% and the friction coefficient by about 18% was observed for carbon implanted titanium with a dose of 1 {times} 10{sup 17} C{sup +} cm{sup {minus}2}; this effect corresponds to a good correlation between wettability and friction coefficient after C{sup +} implantation in titanium. It was concluded that the reduction of the friction coefficient with monoenergetic C{sup +} implanted titanium is 3.7 times lower compared with those of pure titanium.

  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. 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

  3. Ion Implantation in Polymers.

    DTIC Science & Technology

    1983-08-01

    since degree of crystallinity had little effect on this result. a"’ Another physical property which undergoes changes upon irradiation largely because... electronic conductivity, which appears to scale approximately with the electronegativity of the species, once the damage induced conductivity effect ...Proceedings of the 2nd International Conference on Radiation Effects in Insulators to be published as a special issue of "Nuclear Instruments & Methods

  4. The Effect of Thermal Annealing on Structural-phase Changes in the Ni-Ti Alloy Implanted with Krypton Ions

    NASA Astrophysics Data System (ADS)

    Poltavtseva, V. P.; Kislitsin, S. B.; Ghyngazov, S. A.

    2016-06-01

    The influence of thermal annealing within the temperature range 100-300°C on the structural-phase state of a Ni-Ti alloy with shape memory effect (SME) implanted with 84Kr ions at the energies E = 280 keV and 1.75 MeV/nucl and the fluences within 5·1012-1·1020 ion/m2 is investigated. For the samples modified by 84Kr ions at E = 1.75 MeV/nucl up to the fluences 1·1020 and 5·1012 ion/m2, the formation of a martensitic NiTi phase with the B19 ' structure, responsible for the SME, is revealed at the annealing temperatures 100 and 300°C, respectively, in the near-surface region corresponding to the outrange area. This is accompanied by the formation of nanosized NiTi particles in the R-phase. As the implantation fluence increases, the probability of their formation decreases. It is shown that annealing of the implanted structures can increase the strength of the Ni-Ti alloy. The degree of hardening is determined by the value of annealing temperature, and an increase in strength is primarily due to ordering of the radiation-induced defect structures (phases). A correlation between the onset temperature of a forward martensitic transition and the structural-phase state of the thermally annealed Ni-Ti alloy is established.

  5. 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.

  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. 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.

  8. 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.

  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 and Backscattering and Channeling Effect Measurements for Analysis of Semiconductor Structures.

    DTIC Science & Technology

    periodic table but different behavior between adjacent elements. During anneal sequences, enhanced diffusion of the implanted species towards the surface was found. Backscattering and channeling effect measurements were directed toward determination of the depth distribution and lattice location of dopant species and toward evaluation of the composition of dielectric layers on semiconductors. Diffusion and alloying behavior were also investigated.

  11. 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.

  12. High-dose boron and silver ion implantation into PMMA probed by slow positrons: Effects of carbonization and formation of metal nanoparticles

    NASA Astrophysics Data System (ADS)

    Kavetskyy, T.; Iida, K.; Nagashima, Y.; Kuczumow, A.; Šauša, O.; Nuzhdin, V.; Valeev, V.; Stepanov, A. L.

    2017-01-01

    The Doppler broadening slow positron beam spectroscopy (SPBS) data for the previously observed effect of carbonization in high-dose (>1016 ion/cm2) 40 keV boron-ion-implanted polymethylmethacrylate (B:PMMA) and another one obtained for the effect of formation of metal nanoparticles in high-dose 30 keV silver-ion-implanted polymer (Ag:PMMA) are compared. Following to the Doppler broadening SPBS results, a difference in the high-dose ion-irradiation-induced processes in B:PMMA and Ag:PMMA is detected.

  13. The effects of ion implantation on the tribology of perfluoropolyether-lubricated 440C stainless steel couples

    NASA Technical Reports Server (NTRS)

    Shogrin, Bradley; Jones, William R., Jr.; Wilbur, Paul J.; Pilar, Herrera-Fierro; Williamson, Don L.

    1995-01-01

    The lubricating lifetime of thin films of a perfluoropolyether (PFPE) based on hexafluoropropene oxide in the presence of ion implanted 440C stainless steel is presented. Stainless steel discs, either unimplanted or implanted with N2, C, Ti, Ti + N2, or Ti + C had a thin film of PFPE (60-400 A) applied to them reproducibly (+/- 20 percent) and uniformly (+/- 15 percent) using a device developed for this study. The lifetimes of these films were quantified by measuring the number of sliding-wear cycles required to induce an increase in the friction coefficient from an initial value characteristic of the lubricated wear couple to a final, or failure value, characteristic of an unlubricated, unimplanted couple. The tests were performed in a dry nitrogen atmosphere (less than 1 percent RH) at room temperature using a 3 N normal load with a relative sliding speed of 0.05 m/s. The lubricated lifetime of the 440C couple was increased by an order of magnitude by implanting the disc with Ti. Ranked from most to least effective, the implanted species were: Ti; Ti+C; unimplanted; N2; C approximately equals Ti+N2. The mechanism postulated to explain these results involves the formation of a passivating or reactive layer which inhibits or facilitates the production of active sites. The corresponding surface microstructures induced by ion implantation, obtained using x-ray diffraction and conversion electron Mossbauer spectroscopy, ranked from most to least effective in enhancing lubricant lifetime were: amorphous Fe-Cr-Ti; amorphous Fe-Cr-Ti-C + TiC; unimplanted; epsilon-(Fe,Cr)(sub x)N, x = 2 or 3; amorphous Fe-Cr-C approximately equals amorphous Fe-Cr-Ti-N.

  14. 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.

  15. Effect of argon ion implantation on the microstructure and electrical conductivity of a polymer based bakelite RPC detector material

    NASA Astrophysics Data System (ADS)

    Kumar, K. V. Aneesh; Munirathnamma, L. M.; Ningaraju, S.; Ranganathaiah, C.; Nambissan, P. M. G.; Ravikumar, H. B.

    2017-05-01

    Positron annihilation lifetime spectroscopy (PALS) and Doppler broadening spectroscopy were used to explore the ion implantation induced microstructural modification and the electrical conductivity of Bakelite Resistive Plate Chamber detector material used in high energy physics experiments. Samples of Bakelite polymers were exposed to 150 keV of argon (Ar) ions in the fluence of 1013 to 1015 ions cm-2. Positron lifetime parameters viz., o-Ps lifetime and its intensity showed decrease in free volume size up on higher implantation fluences indicates the cross linking and filling up of interior voids by the implanted Ar ions. It was found that cross linking in the Bakelite polymer increases significantly with increasing implantation fluences compliment well with the X-Ray Diffraction (XRD) results. The reduction in electrical conductivity of Bakelite material after implantation is also correlated to the conducting pathways and cross links in the polymer matrix. The calculated S parameter exhibits an inverse behavior with the dc electrical conductivity.

  16. 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)

  17. Chemical effect of inert argon beam on nitride nanolayer formed by ion implantation into GaAs surface

    NASA Astrophysics Data System (ADS)

    Mikoushkin, V. M.

    2010-12-01

    The composition of a nitride nanolayer formed on a GaAs(100) surface by the implantation of ions with an energy of E i = 2.5 keV and the chemical state of nitrogen in this layer have been studied by the method of Auger electron spectroscopy. It is established that, in addition to GaN, a GaAsN solid solution phase is formed in the ion-implanted layer. The energies of N KVV Auger electron transitions in these phases are determined as E A (GaN) = 379.8 ± 0.2 eV and E A (GaAsN) = 382.8 ± 0.2 eV (relative to the Fermi level), which allowed the distribution of nitrogen between these phases to be evaluated as [N(GaN)] = 70% and [N(GaAsN)] = 30%. It is established that an argon ion beam produces a chemical effect on the nitride layer, which is related to a cascade mixing of the material. Under the action of the argon ion bombardment, the distribution of nitrogen in the indicated phases changes to opposite. As a result a nitride nanolayer is formed in which the narrow-bandgap semiconductor (GaAsN) predominates rather than the wide-bandgap component (GaN).

  18. 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.

  19. 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.

  20. 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.

  1. Effects of incident energy and angle on carbon cluster ions implantation on silicon substrate: a molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Wei, Ye; Sang, Shengbo; Zhou, Bing; Deng, Xiao; Chai, Jing; Ji, Jianlong; Ge, Yang; Huo, Yuanliang; Zhang, Wendong

    2017-09-01

    Carbon cluster ion implantation is an important technique in fabricating functional devices at micro/nanoscale. In this work, a numerical model is constructed for implantation and implemented with a cutting-edge molecular dynamics method. A series of simulations with varying incident energies and incident angles is performed for incidence on silicon substrate and correlated effects are compared in detail. Meanwhile, the behavior of the cluster during implantation is also examined under elevated temperatures. By mapping the nanoscopic morphology with variable parameters, numerical formalism is proposed to explain the different impacts on phrase transition and surface pattern formation. Particularly, implantation efficiency (IE) is computed and further used to evaluate the performance of the overall process. The calculated results could be properly adopted as the theoretical basis for designing nano-structures and adjusting devices’ properties. Project supported by the National Natural Science Foundation of China (Nos. 51622507, 61471255, 61474079, 61403273, 51502193, 51205273), the Natural Science Foundation of Shanxi (Nos. 201601D021057, 201603D421035), the Youth Foundation Project of Shanxi Province (Nos. 2015021097), the Doctoral Fund of MOE of China (No. 20131402110013), the National High Technology Research and Development Program of China (No. 2015AA042601), and the Specialized Project in Public Welfare from The Ministry of Water Resources of China (Nos. 1261530110110).

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Effects of Ion Implantation on in Vitro Pollen Germination and Cellular Organization of Pollen Tube in Pinus thunbergii Parl. (Japanese Black Pine)

    NASA Astrophysics Data System (ADS)

    Li, Guoping; Huang, Qunce; Yang, Lusheng; Dai, Ximei; Qin, Guangyong; Huo, Yuping

    2006-09-01

    Low-energy ion implantation, as a new technology to produce mutation in plant breeding, has been widely applied in agriculture in China. But so far there is a little understanding of the underlying mechanisms responsible for its biological effects at the cellular level. Here we report the biological effects of a nitrogen ion beams of 30 keV on the pollen grains of Pinus thunbergii Parl. In general, ion implantation inhibited pollen germination. The dose-response curve presented a particular saddle-like pattern. Ion implantation also changed the dimension of the elongated tubes and significantly induced tip swelling. Confocal microscopy indicated that the pollen tube tips in P. thunbergii contained an enriched network of microtubules. Ion implantation led to the disruption of microtubules especially in swollen tips. Treatment with colchicine demonstrated that tip swelling was caused by the disruption of microtubules in the tip, indicating a unique role for microtubules in maintaining the tip integrality of the pollen tube in conifer. Our results suggest that ion implantation induce the disruption of microtubule organization in pollen and pollen tubes and subsequently cause morphological abnormalities in the pollen tubes. This study may provide a clue for further investigation on the interaction between low-energy ion beams and pollen tube growth.

  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. 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.

  11. 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.

  12. Who make transparent ZnO colorful? - Ion implantation and thermal annealing effects

    NASA Astrophysics Data System (ADS)

    Chen, Y. N.; Zheng, C. C.; Ning, J. Q.; Wang, R. X.; Ling, C. C.; Xu, S. J.

    2016-11-01

    ZnO has re-attracted considerable interest as a wide band gap semiconductor and energy material in recent years. When most of the near-band-edge exciton sharp lines in the ultraviolet spectral region have been firmly identified, defect origins of broad color emissions are still open to debate. By implanting Cu+ and Zn+ ions into high quality ZnO single crystal, respectively, and investigating their photoluminescence spectra at different temperatures, we firmly show that the structured green emission band is indeed associated with copper impurity. Incorporation of excess Zn ions into ZnO results in a structureless red emission band with a nearly perfect Gaussian lineshape. The pure electronic level locations of these two color emission bands were inclusively determined by using generalized multiple Brownian oscillator model when the simultaneous multiphonon emission was taken into account. The nature of the two colorful luminescent centers, including their charge states, was discussed with the aid of the latest theoretical results on different point defects and their optical transitions in ZnO.

  13. Effects of the implantation of Sn ions on W matrix's chemical state, crystal structure and hardness

    NASA Astrophysics Data System (ADS)

    Mu, Z. X.; Sun, J. Z.; Wang, H.; Wang, Y. M.

    2017-09-01

    Prior to the practical application of liquid metals as facing material for fusion reactor, the nature of the interaction layer between liquid metal and tungsten substrate should be studied deeply. In the present work, by means of ion implantation technique using a metal vapor vacuum arc source (MEVVA), Sn ions were injected into a W matrix and a W-Sn modified layer was prepared. The chemical state, crystal structure and nano-indentation hardness of the modified layer were investigated and characterized with the use of X-ray photoelectron spectroscopy (XPS), an X-ray diffractometer (XRD) and a nano-indentor. The results indicate that, after the injection of Sn ions into the W matrix, Sn atoms interacted intensively with W, leading to the generation of a large number of point defects (such as vacancies and self-interstitial atoms) and the decrease of average grain size from 16.7 to 11.9 nm. Additionally, chemical shifts appeared, i.e., the binding energy values of W 4f7/2, W 4f5/2, W 5p3/2 and W 4p1/2 in the modified layer was reduced by 0.3 eV, 0.3 eV, 0.4 eV, 1-1.4 eV, respectively. The binding energy values of Sn 3d5/2 and Sn 3d3/2 decreased, with a chemical shift of 0.6-0.7 eV and 0.1-0.3 eV, respectively. The nano-indentation hardness of the modified layer was enhanced; specifically, when the indentation depth was 26.3 nm, the hardness reached a peak value of 13.8 GPa. In the modified layer, the surface chemical states are quite complex, mainly including SnO, WO3, SnO2 and WC.

  14. 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.

  15. The effects on γ-LiAlO2 induced by nuclear energy losses during Ga ions implantation

    NASA Astrophysics Data System (ADS)

    Zhang, Jing; Song, Hong-Lian; Qiao, Mei; Yu, Xiao-Fei; Wang, Tie-Jun; Wang, Xue-Lin

    2017-09-01

    To explore the evolution of γ-LiAlO2 under ion irradiation at low energy, we implanted Ga ions of 30, 80 and 150 keV at fluences of 1 × 1014 and 1 × 1015 ions/cm2 in z-cut γ-LiAlO2 samples, respectively. The implantation resulted in damage regions dominated by nuclear energy losses at depth of 232 Å, 514 Å, and 911 Å beneath the surface, respectively, which was simulated by the Stopping and Range of Ions in Matter program. The irradiated γ-LiAlO2 were characterized with atomic force microscope, Raman spectroscopy, X-ray diffraction and Rutherford backscattering in a channeling mode for morphology evolution, structure information and damage profiles. The interesting and partly abnormal results showed the various behaviors in modification of surface by Ga ions implantation.

  16. Effects of nickel ions implantation and subsequent thermal annealing on structural and magnetic properties of titanium dioxide

    NASA Astrophysics Data System (ADS)

    Vakhitov, I. R.; Lyadov, N. M.; Valeev, V. F.; Nuzhdin, V. I.; Tagirov, L. R.; Khaibullin, R. I.

    2014-12-01

    Wide bandgap semiconducting rutile (TiO2) doped with 3d-elements is a promising material for spintronic applications. In our work a composite material of TiO2:Ni has been formed by using implantation of Ni+ ions into single-crystalline (100)- and (001)- plates of TiO2. Sub-micron magnetic layers of TiO2 containing nickel dopant have been obtained at high implantation fluence of 1×1017 ion/cm2. A part of the implanted samples was then annealed in vacuum at different temperatures Tann = 450-1200 K for 30 min. The influence of the implantation fluence, crystalline orientation, as well as subsequent annealing on the structural and magnetic properties of the nickel-implanted TiO2 have been investigated by using X-ray photoelectron spectroscopy, scanning electron microscopy and coil magnetometry techniques.

  17. Effects of CoCr metal wear debris generated from metal-on-metal hip implants and Co ions on human monocyte-like U937 cells.

    PubMed

    Posada, Olga M; Tate, Rothwelle J; Grant, M Helen

    2015-03-01

    Hip resurfacing with cobalt-chromium (CoCr) alloy was developed as a surgical alternative to total hip replacement. However, the biological effects of nanoparticles generated by wear at the metal-on-metal articulating surfaces has limited the success of such implants. The aim of this study was to investigate the effects of the combined exposure to CoCr nanoparticles and cobalt ions released from a resurfacing implant on monocytes (U937 cells) and whether these resulted in morphology changes, proliferation alterations, toxicity and cytokine release. The interaction between prior exposure to Co ions and the cellular response to nanoparticulate debris was determined to simulate the situation in patients with metal-on-metal implants receiving a second implant. Effects on U937 cells were mainly seen after 120h of treatment. Prior exposure to Co ions increased the toxic effects induced by the debris, and by Co ions themselves, suggesting the potential for interaction in vivo. Increased TNF-α secretion by resting cells exposed to nanoparticles could contribute to osteolysis processes in vivo, while increased IFN-γ production by activated cells could represent cellular protection against tissue damage. Data suggest that interactions between Co ions and CoCr nanoparticles would occur in vivo, and could threaten the survival of a CoCr metal implant. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Effect of titanium ion implantation and the gas atmosphere on the electrophysical properties of alumina

    NASA Astrophysics Data System (ADS)

    Kabyshev, A. V.; Konusov, F. V.

    2007-06-01

    The energy and kinetic characteristics of the dark conductivity and photoconductivity of polycrystalline alumina irradiated by titanium ions and then annealed in vacuum and air have been studied. The effect of temperature on the properties and electron-transport mechanisms is determined. In the air pressure range from 105 to 1 Pa, the electrophysical properties are reversible. A semiconductor coating can be formed on the alumina surface via vacuum annealing; when heated in air, it becomes insulating. The reverse transition is also possible. These modifications are related to the formation of defects, accumulation of oxygen-containing complexes, and changes in the stoichiometric compositions of the compounds synthesized by the ion thermal treatment.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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].

  4. Suppression of the internal electric field effects in ZnO/Zn(0.7)Mg(0.3)O quantum wells by ion-implantation induced intermixing.

    PubMed

    Davis, J A; Dao, L V; Wen, X; Ticknor, C; Hannaford, P; Coleman, V A; Tan, H H; Jagadish, C; Koike, K; Sasa, S; Inoue, M; Yano, M

    2008-02-06

    Strong suppression of the effects caused by the internal electric field in ZnO/ZnMgO quantum wells following ion-implantation and rapid thermal annealing, is revealed by photoluminescence, time-resolved photoluminescence, and band structure calculations. The implantation and annealing induces Zn/Mg intermixing, resulting in graded quantum well interfaces. This reduces the quantum-confined Stark shift and increases electron-hole wavefunction overlap, which significantly reduces the exciton lifetime and increases the oscillator strength.

  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. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Method of making V-MOS field effect transistors utilizing a two-step anisotropic etching and ion implantation

    NASA Technical Reports Server (NTRS)

    Jhabvala, M. D. (Inventor)

    1981-01-01

    A method of making V-MOS field effect transistors is disclosed wherein a masking layer is first formed over a surface of a crystalline substrate. An aperture is then formed in the masking layer to expose the surface of the substrate. An anisotropic etchant is applied to the exposed surface so that a groove having a decreasing width within increasing depth is formed. However, the etch is not allowed to go to completion with the result that a partially formed V-shaped groove is formed. Ions are accelerated through the aperture for implantation in the crystalline substrate in the lower portion of the partially formed V-shaped groove. Thereafter, an anisotropic etchant is reapplied to the partially formed V-shaped groove, and the etch is allowed to go to completion.

  11. 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.

  12. Temperature dependence and annealing effects of absorption edges for selenium quantum dots formed by ion implantation in silica glass

    SciTech Connect

    Ueda, A.; Wu, M.; Mu, R.

    1998-12-31

    The authors have fabricated Se nanoparticles in silica substrates by ion implantation followed by thermal annealing up to 1000 C, and studied the Se nanoparticle formation by optical absorption spectroscopy, Rutherford backscattering spectrometry, X-ray diffraction, and transmission electron microscopy. The sample with the highest dose (1 {times} 10{sup 17} ions/cm{sup 2}) showed the nanoparticle formation during the ion implantation, while the lower dose samples (1 and 3 {times} 10{sup 16} ions/cm{sup 2}) required thermal treatment to obtain nano-sized particles. The Se nanoparticles in silica were found to be amorphous. After thermal annealing, the particle doses approached the value of bulk after thermal annealing. The temperature dependent absorption spectra were also measured for this system in a temperature range from 15 to 300 K.

  13. Effect of the implantation dose and annealing time on the luminescence properties of (113) defects in silicon implanted by oxygen ions

    NASA Astrophysics Data System (ADS)

    Sobolev, N. A.; Kalyadin, A. E.; Aruev, P. N.; Zabrodskii, V. V.; Shek, E. I.; Shtel'makh, K. F.; Karabeshkin, K. V.

    2016-12-01

    The photoluminescence properties of (113) defects formed in a silicon structure after the implantation by oxygen ions with an energy of 350 keV and doses of 1.7 × 1013-1.7 × 1015 cm-2 and the subsequent annealing at a temperature of 700°C for 0.5-2.0 h in a chlorine-containing atmosphere have been investigated. Regardless of the implantation dose and annealing time, the photoluminescence spectra are dominated by the line at a wavelength of 1.37 μm, which is attributed to a (113) defect. The dependences of the line intensity on the implantation dose and annealing time are characterized by curves with maxima. As the measurement temperature increases in the range from 64 to 120 K, the line intensity decreases monotonically.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. Effects of calcium phosphate coating to SLA surface implants by the ion-beam-assisted deposition method on self-contained coronal defect healing in dogs.

    PubMed

    Yoon, Heun-Joo; Song, Ji-Eun; Um, Yoo-Jung; Chae, Gyung Joon; Chung, Sung-Min; Lee, In-Seop; Jung, Ui-Won; Kim, Chang-Sung; Choi, Seong-Ho

    2009-08-01

    The aim of this study was to evaluate the healing of self-contained coronal defects on a sand-blasted, large-grit, acid-etched (SLA) surface implant, which had a calcium phosphate (CaP) coating applied by ion-beam-assisted deposition (IBAD). We also evaluated the effect of heating the coating to different temperatures. The CaP-coated SLA implants exhibited a slightly larger bone healing capacity in the self-contained coronal defect than SLA implants, indicating that combining SLA surface implants and a CaP coating by the IBAD method had synergistic effects on bone healing. There was no difference in the healing capacity between 350 degrees C and 450 degrees C heat treatment of the coating layer.

  19. 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.}

  20. Study of the effect of ion implantation on the electrical and microstructural properties of tin-doped indium oxide thin films

    NASA Astrophysics Data System (ADS)

    Shigesato, Yuzo; Paine, David C.; Haynes, T. E.

    1993-04-01

    Ion implantation of H2+ or O+ ions in the range 0-1.7×1015 and 0-1.3×1015/cm2, respectively, was used to investigate the effect of implant-induced damage on the electrical properties of Sn-doped In2O3 (ITO) films deposited by electron-beam evaporation on SiO2-coated soda-lime glass substrates. The films were characterized as a function of implant dose using low-temperature Hall effect, resistivity, optical transmissivity, x-ray diffraction, and transmission electron microscopy (TEM). A systematic decrease in both carrier density (n) and Hall mobility (μ) was observed with increasing dose of either implant species. The electronic results were analyzed using charged and neutral impurity scattering models which suggest that the observed changes are due to the degradation of electrically active donor centers and the generation of the neutral scattering centers. The microstructure of the implanted films, as revealed by TEM and x-ray diffraction, is consistent with the presence of significant dynamic recovery during implantation.

  1. 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.

  2. 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.

  3. 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.

  4. The Effect of Annealing at 1500 C on Migration and Release of Ion Implanted Silver in CVD Silicon Carbide

    SciTech Connect

    HJ MacLean; RG Ballinger; LE Kolaya; SA Simonson; N Lewis; M Hanson

    2004-10-07

    The transport of silver in CVD {beta}-SiC has been studied using ion implantation. Silver ions were implanted in {beta}-SiC using the ATLAS accelerator facility at the Argonne National Laboratory. Ion beams with energies of 93 and 161 MeV were used to achieve deposition with peak concentrations at depths of approximately 9 and 13 {micro}m, respectively. As-implanted samples were then annealed at 1500 C for 210 or 480 hours. XPS, SEM, TEM, STEM, and optical methods were used to analyze the material before and after annealing. Silver concentration profiles were determined using XPS before and after annealing. STEM and SEM equipped with quantitative chemical analysis capability were used to more fully characterize the location and morphology of the silver before and after annealing. The results show that, within the uncertainty of measurement techniques, there is no silver migration, via either inter- or intragrannular paths, for the times and temperature studied. Additionally, the silver was observed to phase separate within the SiC after annealing. The irradiation damage from the implantation process resulted in a three-layer morphology in the as-implanted condition: (1) a layer of unaltered SiC, followed by (2) a layer of crystallized SiC, followed by (3) an amorphized layer which contained essentially all of the implanted silver. After annealing the layer structure changed. Layer 1 was unaltered. The grains in layer 2 recrystallized to form an epitaxial (columnar) layer. Layer 3 recrystallized to form a fine grain equiaxed layer. The results of this work do not support the long held assumption that silver release from CVD SiC, used for gas-reactor coated particle fuel, is dominated by grain boundary diffusion.

  5. 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.

  6. Applications of ion implantation to high performance, radiation tolerant silicon solar cells

    NASA Technical Reports Server (NTRS)

    Kirkpatrick, A. R.; Minnucci, J. A.; Matthei, K. W.

    1979-01-01

    Progress in the development of ion implanted silicon solar cells is reported. Effective back surface preparation by implantation, junction processing to achieve high open circuit voltages in low-resistivity cells, and radiation tolerance cells are among the topics studied.

  7. 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.

  8. 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.

  9. The Study of Effective Work Function Modulation by As Ion Implantation in TiN/TaN/HfO2 Stacks

    NASA Astrophysics Data System (ADS)

    Singanamalla, Raghunath; Yu, Hong Yu; Janssens, Tom; Kubicek, Stefan; Meyer, Kristin De

    2007-04-01

    The impact on the metal gate effective work function (EWF) of As ion implantation through TiN/TaN/HfO2 gate stack was investigated. An As implantation at 20 KeV reduces the flat-band voltage (VFB) for TiN/TaN/HfO2 capacitors (or equivalently reduces the EWF) by a maximum of 600 mV at a dose of 5× 1015 cm-2. This VFB reduction is correlated to the As pile-up at the TaN-HfO2 interface, as evidenced by a secondary ion mass spectroscopy (SIMS) study. The As ion accumulation at the interface of the gate electrode-dielectric interface is suggested to induce an interface dipole, contributing to the observed phenomena.

  10. Formation of NiSi{sub 2} nanoclusters by Ni ion implantation into Si(100) and the effect of preinjection of Si{sub 2}{sup +} ions

    SciTech Connect

    Sundaravel, B.; Kalavathi, S.; SanthanaRaman, P.; Satyam, P. V.; Nair, K.G.M.

    2012-06-05

    Cluster ions can produce surface craters and amorphous ion tracks in semiconductors. This process in combination with defect mediated diffusion can be applied to fabricate buried nanowires. 1.4 MeV Si{sub 2}{sup +} ions at low fluences and 400 keV Ni{sup +} ions at high fluence are implanted into Si(100) and annealed at 600 deg. C. NiSi{sub 2} nanoclusters are formed and TEM measurements show surface craters of around 30 nm diameter which are followed by amorphous tracks of diameter 15 nm caused by the Si{sub 2}{sup +} ions in Si substrate. 50 nm long finger like buried vertical nanowires from the silicide clusters are formed along the amorphous track which is due to diffusion of Nickel atoms towards the surface mediated by the defects in the track. It is a step closer to the fabrication of buried nanowires.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Effect of surface texture by ion beam sputtering on implant biocompatibility and soft tissue attachment

    NASA Technical Reports Server (NTRS)

    Gibbons, D. F.

    1977-01-01

    The objectives in this report were to use the ion beam sputtering technique to produce surface textures on polymers, metals, and ceramics. The morphology of the texture was altered by varying both the width and depth of the square pits which were formed by ion beam erosion. The width of the ribs separating the pits were defined by the mask used to produce the texture. The area of the surface containing pits varies as the width was changed. The biological parameters used to evaluate the biological response to the texture were: (1) fibrous capsule and inflammatory response in subcutaneous soft tissue; (2) strength of the mechanical attachment of the textured surface by the soft tissue; and (3) morphology of the epidermal layer interfacing the textured surface of percutaneous connectors. Because the sputter yield on teflon ribs was approximately an order of magnitude larger than any other material the majority of the measurements presented in the report were obtained with teflon.

  3. Effects of Ion Implantation on Cavitation Erosion of a Cobalt Based Metal/Carbide Alloy.

    DTIC Science & Technology

    1987-09-01

    L_____ L -_ 0nion source. The samlies were heat sunk onto100 200 300 400o100 DEPH a water-cooled holder during implantat ion to limnit tihe temerature...by water test times of between 20 and 35 h, are shown jets ( pump circulated test water) through the in Fig. 2. SEM micrographs showing the dam...qualitative measure of the relative amounts of the - hcp and fcc phases in the alloy [4]. Calculations based on the mass adsorbtion coefficient for

  4. 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.

  5. Collective optical Kerr effect exhibited by an integrated configuration of silicon quantum dots and gold nanoparticles embedded in ion-implanted silica

    NASA Astrophysics Data System (ADS)

    Torres-Torres, C.; López-Suárez, A.; Can-Uc, B.; Rangel-Rojo, R.; Tamayo-Rivera, L.; Oliver, A.

    2015-07-01

    The study of the third-order optical nonlinear response exhibited by a composite containing gold nanoparticles and silicon quantum dots nucleated by ion implantation in a high-purity silica matrix is presented. The nanocomposites were explored as an integrated configuration containing two different ion-implanted distributions. The time-resolved optical Kerr gate and z-scan techniques were conducted using 80 fs pulses at a 825 nm wavelength; while the nanosecond response was investigated by a vectorial two-wave mixing method at 532 nm with 1 ns pulses. An ultrafast purely electronic nonlinearity was associated to the optical Kerr effect for the femtosecond experiments, while a thermal effect was identified as the main mechanism responsible for the nonlinear optical refraction induced by nanosecond pulses. Comparative experimental tests for examining the contribution of the Au and Si distributions to the total third-order optical response were carried out. We consider that the additional defects generated by consecutive ion irradiations in the preparation of ion-implanted samples do not notably modify the off-resonance electronic optical nonlinearities; but they do result in an important change for near-resonant nanosecond third-order optical phenomena exhibited by the closely spaced nanoparticle distributions.

  6. Transversal Kerr effect of In1- x Mn x As layers prepared by ion implantation followed by pulsed laser annealing

    NASA Astrophysics Data System (ADS)

    Gan'shina, Elena; Golik, Leonard; Kun'kova, Zoya; Bykov, Igor; Novikov, Andrey; Rukovishnikov, Alexander; Yuan, Ye; Zykov, Georgy; Böttger, Roman; Zhou, Shengqiang

    2016-07-01

    In1- x Mn x As (x = 6.9%) layers prepared by ion implantation and subsequent pulsed laser annealing have been studied using the magnetooptical transversal Kerr effect (TKE) and spectral ellipsometry. Ellipsometry data reveal the good crystal quality of the layers. The samples show ferromagnetic behaviour below 77 K. Near the absorption edge of the parent InAs semiconductor, large TKE values are observed. In the energy regions of the transitions in the Γ and L critical points of the InAs Brillouin zone, there are several clearly defined structures in the low-temperature TKE spectra. We have calculated the spectral dependences of the diagonal and nondiagonal components of the permittivity tensor (PT), as well as the spectrum of magnetic circular dichroism (MCD) for our samples. A number of extrema in the obtained MCD and PT spectra are close to the energies of transitions in the critical points of the parent semiconductor band structure, which confirms the intrinsic ferromagnetism of the Mn-doped InAs layers.

  7. 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.

  8. The microstructural evolution of ultrananocrystalline diamond films due to P ion implantation process—the annealing effect

    SciTech Connect

    Lin, Sheng-Chang; Yeh, Chien-Jui; Leou, Keh-Chyang; Kurian, Joji; Lin, I.-Nan; Dong, Chung-Li; Niu, Huan

    2014-11-14

    The microstructural evolution of UNCD films which are P-ion implanted and annealed at 600 °C (or 800 °C) is systematically investigated. The difference of interaction that the UNCD content undergoes along the trajectory of the incident P-ions is reflected in the alteration of the granular structure. In regions where the P-ions reside, the “interacting zone,” which is found at about 300 nm beneath the surface of the films, coalescence of diamond grains occurs inducing nano-graphitic clusters. The annealing at 600 °C (or 800 °C) heals the defects and, in some cases, forms interconnected graphitic filaments that result in the decrease in surface resistance. However, the annealing at 600 °C (800 °C) induces marked UNCD-to-Si layers interaction. This interaction due to the annealing processes hinders the electron transport across the interface and degrades the electron field emission properties of the UNCD films. These microstructural evolution processes very well account for the phenomenon elaborating that, in spite of enhanced conductivity of the UNCD films along the film's surface due to the P-ion implantation and annealing processes, the electron field emission properties for these UNCD films do not improve.

  9. 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.

  10. 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.

  11. In vivo evaluation of antithrombogenicity and surface analysis of ion-implanted silicone rubber

    NASA Astrophysics Data System (ADS)

    Suzuki, Y.; Kusakabe, M.; Iwaki, M.; Akiba, H.; Kusakabe, K.

    The chemical and physical structure of ion-implanted silicone rubbers has been studied in order to analyze their blood compatibility such as reduction of platelet accumulation owing to ion implantation. H +2, He +, C +, O +, O +2, N +, N +2, Ne +, Na +, Ar +, K +, and Kr + ion implantations were performed at an energy of 150 keV with fluences between 1 × 10 17 and 3 × 10 17 ions/cm 2 at room temperature. Results of FT-IR-ATR showed that ion implantation broke the original chemical bond to form new radicals such as OH, >C = O, SiH, and CH 2. The formation of these radicals depended on the ion species employed: >C = O formation by O + or O +2 implantation and formation of amines by N + or N +2 implantation. The results of Raman spectroscopy showed that ion implantation always produced a peak at near 1500 cm -1, although the intensity of this peak was dependent on the ion species. The light ions like H +2 and He + were more effective than heavy ions in producing this peak, and O +2 implantation was the most effective on producing amorphous carbon. These results indicated that >C = O and amorphous carbon, generated by O +2 implantation, may improve the antithrombogenicity. The antithrombogenicity was tested by the superior vena cava (SVC) indwelling method for two days in rats with in-111-tropolone-platelets, and by the inferior vena cava (IVC) indwelling method for periods of 1-4 weeks in dogs. Results of the SVC indwelling method showed that platelet accumulation on H +2 and O +2 implanted specimens decreased. In particular 1 × 10 17 O +2/cm 2 implantation caused both accumulation onto specimens and the SVC to decrease. Macroscopic views of the ion-implanted IVC specimens in dogs revealed little thrombus formation. It is concluded that ion implantation into silicone rod is a useful technique to improve its antithrombogenicity.

  12. 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.

  13. 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.

  14. 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.

  15. Ion channeling effects on quantum well intermixing in phosphorus-implanted InGaAsP/InGaAs/InP

    SciTech Connect

    Barba, D.; Salem, B.; Morris, D.; Aimez, V.; Beauvais, J.; Chicoine, M.; Schiettekatte, F.

    2005-09-01

    Photoluminescence, time-resolved photoluminescence, and Raman characterization techniques have been used to study In{sub 0.73}Ga{sub 0.27}As{sub 0.57}P{sub 0.43}/In{sub 0.53}Ga{sub 0.47}As/InP single quantum well heterostructure after 20-keV phosphorus ion implantation followed by rapid thermal annealing. The annealing process induces intermixing in the heterostructures and results in the blueshift of the quantum well peak emission. In order to investigate ion channeling effects on this band-gap tuning process, room-temperature implantations have been performed at tilt angles of 0 deg. and 7 deg. with respect to the sample (001)-growth axis. We show that the ion channeling increases the blueshift from 24 to 42 nm, while it reduces both the density of the nonradiative defects within the active layer and the structure disordering. These features are attributed to the nature of the damage generated by channeled ions. The band-gap increase observed in the sample implanted at 0 deg. is consistent with the formation of a compressive strain at the barrier/quantum well interface, whose intensity is measured by Raman spectroscopy.

  16. Heated ion implantation for high-performance and highly reliable silicon-on-insulator complementary metal-oxide-silicon fin field-effect transistors

    NASA Astrophysics Data System (ADS)

    Mizubayashi, Wataru; Onoda, Hiroshi; Nakashima, Yoshiki; Ishikawa, Yuki; Matsukawa, Takashi; Endo, Kazuhiko; Liu, Yongxun; O'uchi, Shinichi; Tsukada, Junichi; Yamauchi, Hiromi; Migita, Shinji; Morita, Yukinori; Ota, Hiroyuki; Masahara, Meishoku

    2015-04-01

    We have investigated the impact of heated ion implantation (I/I) on the performance and reliability of silicon-on-insulator (SOI) complementary metal-oxide-silicon (CMOS) fin field-effect transistors (FinFETs). An implantation temperature equal to and higher than 400 °C is needed to maintain the crystallinity of the Si substrate during I/I within the experimental conditions of ion species, implantation energy, and ion dose in this study. By heated I/I at 500 °C, the 11-nm-thick SOI layer perfectly maintains the crystallinity even after I/I, and a defect-free crystal is obtained by activation annealing. It was clarified that the cap layer is essential for the suppression of the out-diffusion during heated I/I. Heated I/I on the source and drain improves the on-current-off-current (Ion-Ioff), threshold voltage (Vth) variability, and bias temperature instability (BTI) characteristics of nMOS and pMOS FinFETs as compared with those after room-temperature I/I.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. Turning an organic semiconductor into a low-resistance material by ion implantation.

    PubMed

    Fraboni, Beatrice; Scidà, Alessandra; Cosseddu, Piero; Wang, Yongqiang; Nastasi, Michael; Milita, Silvia; Bonfiglio, Annalisa

    2015-12-01

    We report on the effects of low energy ion implantation on thin films of pentacene, carried out to investigate the efficacy of this process in the fabrication of organic electronic devices. Two different ions, Ne and N, have been implanted and compared, to assess the effects of different reactivity within the hydrocarbon matrix. Strong modification of the electrical conductivity, stable in time, is observed following ion implantation. This effect is significantly larger for N implants (up to six orders of magnitude), which are shown to introduce stable charged species within the hydrocarbon matrix, not only damage as is the case for Ne implants. Fully operational pentacene thin film transistors have also been implanted and we show how a controlled N ion implantation process can induce stable modifications in the threshold voltage, without affecting the device performance.

  2. Turning an organic semiconductor into a low-resistance material by ion implantation

    PubMed Central

    Fraboni, Beatrice; Scidà, Alessandra; Cosseddu, Piero; Wang, Yongqiang; Nastasi, Michael; Milita, Silvia; Bonfiglio, Annalisa

    2015-01-01

    We report on the effects of low energy ion implantation on thin films of pentacene, carried out to investigate the efficacy of this process in the fabrication of organic electronic devices. Two different ions, Ne and N, have been implanted and compared, to assess the effects of different reactivity within the hydrocarbon matrix. Strong modification of the electrical conductivity, stable in time, is observed following ion implantation. This effect is significantly larger for N implants (up to six orders of magnitude), which are shown to introduce stable charged species within the hydrocarbon matrix, not only damage as is the case for Ne implants. Fully operational pentacene thin film transistors have also been implanted and we show how a controlled N ion implantation process can induce stable modifications in the threshold voltage, without affecting the device performance. PMID:27877850

  3. Effect of nitrogen ion implantation on corrosion inhibition of nickel coated 316 stainless steel and correlation with nano-structure

    NASA Astrophysics Data System (ADS)

    Grayeli-Korpi, Ali-Reza; Savaloni, Hadi

    2012-10-01

    The influence of implantation of N+ with 20 keV energy and different fluences in the range of 1 × 1017 and 5 × 1018 ions/cm2 in the nickel coated type 316 stainless steel (SS) on the corrosion inhibition of SS in 3.5 wt% NaCl solution is investigated. The highest available N+ fluence showed highest corrosion inhibition. X-ray diffraction (XRD) analysis showed formation of nickel nitride phases that enhanced by increasing the N+ fluence. Surface morphology was studied by atomic force microscope (AFM) and scanning electron microscope (SEM) before and after corrosion test, respectively. AFM results showed that by increasing N+ fluence surface of the sample becomes smoother that may be the result of heat accumulation during implantation causing higher rate of diffusion in the sample.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Productivity Improvement for the SHX--SEN's Single-Wafer High-Current Ion Implanter

    SciTech Connect

    Ninomiya, Shiro; Ochi, Akihiro; Kimura, Yasuhiko; Yumiyama, Toshio; Kudo, Tetsuya; Kurose, Takeshi; Kariya, Hiroyuki; Tsukihara, Mitsukuni; Ishikawa, Koji; Ueno, Kazuyoshi

    2011-01-07

    Equipment productivity is a critical issue for device fabrication. For ion implantation, productivity is determined both by ion current at the wafer and by utilization efficiency of the ion beam. Such improvements not only result in higher fabrication efficiency but also reduce consumption of both electrical power and process gases. For high-current ion implanters, reduction of implant area is a key factor to increase efficiency. SEN has developed the SAVING system (Scanning Area Variation Implantation with Narrower Geometrical pattern) to address this opportunity. In this paper, three variations of the SAVING system are introduced along with discussion of their effects on fab productivity.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Effect of composition on damage accumulation in ternary ZnO-based oxides implanted with heavy ions

    NASA Astrophysics Data System (ADS)

    Azarov, A. Yu.; Svensson, B. G.; Hallén, A.; Du, X. L.; Kuznetsov, A. Yu.

    2010-08-01

    Thin films of wurtzite MgxZn1-xO (x≤0.3) grown by molecular beam epitaxy and wurtzite CdxZn1-xO (x≤0.05) grown by metal organic chemical vapor deposition were implanted at room temperature with 150 keV Er+ ions and 200 keV Au+ ions in a wide dose range. Damage accumulation was studied by Rutherford backscattering/channeling spectrometry. Results show that the film composition affects the damage accumulation behavior in both MgZnO and CdZnO dramatically. In particular, increasing the Mg content in MgZnO results in enhanced damage accumulation in the region between the bulk and surface damage peaks characteristically distinguished in the pure ZnO. However, the overall damage accumulation in MgZnO layers, as well as in pure ZnO, exhibits saturation with increasing ion dose and MgZnO cannot be amorphized even at the highest ion dose used (3×1016 Er/cm2). Increasing the Cd content in CdZnO affects the saturation stage of the damage accumulation and leads to an enhancement of damage production in both Cd and Zn sublattices.

  20. Ion implantation in compound semiconductors for high-performance electronic devices

    SciTech Connect

    Zolper, J.C.; Baca, A.G.; Sherwin, M.E.; Klem, J.F.

    1996-05-01

    Advanced electronic devices based on compound semiconductors often make use of selective area ion implantation doping or isolation. The implantation processing becomes more complex as the device dimensions are reduced and more complex material systems are employed. The authors review several applications of ion implantation to high performance junction field effect transistors (JFETs) and heterostructure field effect transistors (HFETs) that are based on compound semiconductors, including: GaAs, AlGaAs, InGaP, and AlGaSb.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Effect of Molybdenum Ion Implantation of the Pitting Corrosion of Depleted Uranium - 0.75 Titanium Alloy

    DTIC Science & Technology

    1993-07-01

    present Various coatings phase diagram , the equilibrium structure of DU -0 75 Ti consists of and surface treatments have been explored as protective...the Si, Nb, Zr. and Al on aluminum . Rubio and coworkers" thoug-ot the antlcipsted Mo c•ncentratuon profile. implantation effect comprises a mechanical...than Calculations Show that if the dissolved Mo is evenly distributed in the the alloy in the same solution without motybdate. It repassivates at

  8. Effect of carbon ion implantation on the tribology of metal-on-metal bearings for artificial joints

    PubMed Central

    Koseki, Hironobu; Tomita, Masato; Yonekura, Akihiko; Higuchi, Takashi; Sunagawa, Sinya; Baba, Koumei; Osaki, Makoto

    2017-01-01

    Metal-on-metal (MoM) bearings have become popular due to a major advantage over metal-on-polymer bearings for total hip arthroplasty in that the larger femoral head and hydrodynamic lubrication of the former reduce the rate of wear. However, concerns remain regarding adverse reactions to metal debris including metallosis caused by metal wear generated at the taper-head interface and another modular junction. Our group has hypothesized that carbon ion implantation (CII) may improve metal wear properties. The purpose of this study was to investigate the wear properties and friction coefficients of CII surfaces with an aim to ultimately apply these surfaces to MoM bearings in artificial joints. CII was applied to cobalt-chromium-molybdenum (Co-Cr-Mo) alloy substrates by plasma source ion implantation. The substrates were characterized using scanning electron microscopy and a 3D measuring laser microscope. Sliding contact tests were performed with a simple geometry pin-on-plate wear tester at a load of 2.5 N, a calculated contact pressure of 38.5 MPa (max: 57.8 MPa), a reciprocating velocity of 30 mm/s, a stroke length of 60 mm, and a reciprocating cycle count of 172,800 cycles. The surfaces of the CII substrates were generally featureless with a smooth surface topography at the same level as untreated Co-Cr-Mo alloy. Compared to the untreated Co-Cr-Mo alloy, the CII-treated bearings had lower friction coefficients, higher resistance to catastrophic damage, and prevented the adhesion of wear debris. The results of this study suggest that the CII surface stabilizes the wear status due to the low friction coefficient and low infiltration of partner materials, and these properties also prevent the adhesion of wear debris and inhibit excessive wear. Carbon is considered to be biologically inert; therefore, CII is anticipated to be applicable to the bearing surfaces of MoM prostheses. PMID:28615939

  9. Effect of carbon ion implantation on the tribology of metal-on-metal bearings for artificial joints.

    PubMed

    Koseki, Hironobu; Tomita, Masato; Yonekura, Akihiko; Higuchi, Takashi; Sunagawa, Sinya; Baba, Koumei; Osaki, Makoto

    2017-01-01

    Metal-on-metal (MoM) bearings have become popular due to a major advantage over metal-on-polymer bearings for total hip arthroplasty in that the larger femoral head and hydrodynamic lubrication of the former reduce the rate of wear. However, concerns remain regarding adverse reactions to metal debris including metallosis caused by metal wear generated at the taper-head interface and another modular junction. Our group has hypothesized that carbon ion implantation (CII) may improve metal wear properties. The purpose of this study was to investigate the wear properties and friction coefficients of CII surfaces with an aim to ultimately apply these surfaces to MoM bearings in artificial joints. CII was applied to cobalt-chromium-molybdenum (Co-Cr-Mo) alloy substrates by plasma source ion implantation. The substrates were characterized using scanning electron microscopy and a 3D measuring laser microscope. Sliding contact tests were performed with a simple geometry pin-on-plate wear tester at a load of 2.5 N, a calculated contact pressure of 38.5 MPa (max: 57.8 MPa), a reciprocating velocity of 30 mm/s, a stroke length of 60 mm, and a reciprocating cycle count of 172,800 cycles. The surfaces of the CII substrates were generally featureless with a smooth surface topography at the same level as untreated Co-Cr-Mo alloy. Compared to the untreated Co-Cr-Mo alloy, the CII-treated bearings had lower friction coefficients, higher resistance to catastrophic damage, and prevented the adhesion of wear debris. The results of this study suggest that the CII surface stabilizes the wear status due to the low friction coefficient and low infiltration of partner materials, and these properties also prevent the adhesion of wear debris and inhibit excessive wear. Carbon is considered to be biologically inert; therefore, CII is anticipated to be applicable to the bearing surfaces of MoM prostheses.

  10. 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

  11. The influence of a doping profile on the characteristics of an ion-implanted GaAs field-effect transistor with a Schottky barrier

    SciTech Connect

    Shestakov, A. K. Zhuravlev, K. S.

    2011-12-15

    A GaAs field-effect ion-implanted transistor with a Schottky barrier is simulated. The doping profile obtained when doping through an insulator mask is determined and the dependences of the static transistor characteristics on the parameters of the doping profile are calculated and analyzed. The physical processes controlling the transistor characteristics in the case of a variation in the parameters of its doping profile and the coefficient of compensation of the substrate are studied. Based on calculations, the optimal doping-profile parameters ensuring the best characteristics for transistors are predicted.

  12. 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.

  13. Thermal Behaviour of W+C Ion Implanted Ultra High Molecular Weight Polyethylene (UHMWPE)

    SciTech Connect

    Urkac, E. Sokullu; Oztarhan, A.; Tihminlioglu, F.; Ila, D.; Chhay, B.; Muntele, C.; Budak, S.; Oks, E.; Nikolaev, A.

    2009-03-10

    The aim of this work was to examine thermal behavior of the surface modified Ultra High Molecular Weight Poly Ethylene (UHMWPE ) in order to understand the effect of ion implantation on the properties of this polymer which is widely used especially for biomedical applications. UHMWPE samples were Tungsten and Carbon (W+C) hybrid ion implanted by using Metal Vapour Vacuum Arc (MEVVA) ion implantation technique with a fluence of 10 17 ions/cm2 and extraction voltage of 30 kV. Untreated and surface-treated samples were investigated by Rutherford Back Scattering (RBS) Analysis, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) Spectrometry, Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). This study has shown that ion implantation represents a powerful tool on modifying thermal properties of UHMWPE surfaces. This combination of properties can make implanted UHMWPE a preferred material for biomedical applications.

  14. 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

  15. Analysis of ion-implanted surface and interface structures by computer-simulated backscattering spectra

    NASA Astrophysics Data System (ADS)

    Kido, Y.; Kakeno, M.; Yamada, K.; Kawamoto, J.; Ohsawa, H.

    1985-10-01

    Computer codes for synthesizing random and channeling backscattering spectra have been elaborated to characterize the surface and interface structures formed or modified by ion implantation. Both effects of isotopes and energy fluctuation are taken into account in the spectrum simulation. This backscattering measurement combined with the simulation method is applied to characterization of the N(+)-implanted Al films and to quantitative analysis of chemical reaction and interdiffusion induced by ion-beam mixing. An ion-beam-induced damage profile and its epitaxial recovery of crystallinity are analyzed by the simulation of channeling spectra from ion-implanted Al2O3 substrates.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Ion Profiling of Implanted Dopants in Si (001) with Excess Vacancy Concentration

    SciTech Connect

    Dalponte, M.; Boudinov, H.; Goncharova, L. V.; Feng, T.; Garfunkel, E.; Gustafsson, T.

    2007-09-26

    Medium energy ion scattering (MEIS) was used to study the distribution of ion-implanted As and Sb dopants in Si with excess vacancies and SIMOX substrates as well as the effects of thermal treatments. Extra vacancies in Si were generated by N or O pre-implantation at high temperatures. Under these conditions, effects related to the different chemical nature of the pre-implanted species are expected. The annealing behavior and depth distribution of the Sb atoms differed for O compared to N pre-implanted Si. After long annealing times, the oxygen containing samples (SIMOX and O pre-implanted Si) presented higher substitutionality. The nitrogen pre-implanted Si presented the lowest amount of segregated Sb and a more uniform dopant distribution. For both N and O pre-implanted samples a large dopant loss to the atmosphere during annealing was observed.

  7. Effect of Ar+ ion post-irradiation on crystal structure, magnetic behavior and optical band gap of Co-implanted ZnO wafers

    NASA Astrophysics Data System (ADS)

    Xu, N. N.; Li, G. P.; Lin, Q. L.; Liu, H.; Bao, L. M.

    2016-12-01

    Single crystals wurtzite ZnO with (001) orientation were implanted with Co+ ions at room temperature (RT). To tune their magnetic behavior as well as the band gap of the implanted wafers, Ar+ ion post-irradiation (PI) was performed using the calculated energy and ion dose. The formed Co clusters present in the high dose Co-implanted ZnO wafer were observed to be absent after the PI, which is quite different from the low dose doped one. It is found that all the implanted samples showed a giant magnetic moment and a narrowing optical band gap, and that the post-irradiated ones exhibited an even further redshifted absorption edge and ferromagnetic behavior but with saturation magnetization (MS) drastically decreased.

  8. Study on the growth and the photosynthetic characteristics of low energy C(+) ion implantation on peanut.

    PubMed

    Han, Yuguo; Xu, Lei; Yang, Peiling; Ren, Shumei

    2013-01-01

    Employing the Nonghua 5 peanut as experimental material, the effects of low energy C(+) ion implantation on caulis height, root length, dry weight, photosynthetic characteristics and leaf water use efficiency (WUE) of Peanut Ml Generation were studied. Four fluences were observed in the experiment. The results showed that ion implantation harmed the peanut seeds because caulis height, root length and dry weight all were lower in the treatments than in CK, and the harm was aggravated with the increase of ion fluence. Both Pn and Tr show a saddle-shape curve due to midday depression of photosynthesis. Low fluence of low energy C(+) ion implantation could increase the diurnal average Pn of peanut. The diurnal variation of Tr did not change as significantly as Pn. The light saturation point (LSP) was restrained by the ions. After low energy C(+) ion implantation, WUE was enhanced. When the fluence increased to a certain level, the WUE began to decrease.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Human alveolar bone cell adhesion and growth on ion-implanted titanium.

    PubMed

    Nayab, S N; Jones, F H; Olsen, I

    2004-06-15

    Surface characteristics play a vital role in determining the biocompatibility of materials used as bone implants. Calcium ion implantation of titanium was previously reported to enhance osseointegration and bone formation in vivo, although the lack of consistent and reproducible effects highlight the need to understand the basic mechanisms involved in the response of target cells to such surfaces. The aim of this study was therefore to measure the precise effects of ion implantation of titanium on bone cells in vitro. Alveolar bone cells were seeded on the surface of polished titanium disks implanted with calcium, potassium, and argon ions. Using radioisotopically tagged bone cells, the results showed that although the calcium ion implanted surface reduced cell adhesion, it nevertheless significantly enhanced cell spreading and subsequent cell growth. In contrast, few differences in bone cell behavior were observed between the potassium- and argon-implanted titanium and the control nonimplanted titanium disks. These findings suggest the possibility that the calcium-implanted surface may significantly affect the biocompatibility of titanium implants by enhancing bone cell growth. Surface modification by ion implantation could thus prove to be a valuable tool for improving the clinical efficacy of titanium for bone repair and regeneration in vivo. Copyright 2004 Wiley Periodicals, Inc.

  14. Decrease in work function of boron ion-implanted ZnO thin films.

    PubMed

    Heo, Gi-Seok; Hong, Sang-Jin; Park, Jong-Woon; Choi, Bum-Ho; Lee, Jong-Ho; Shin, Dong-Chan

    2007-11-01

    We have fabricated boron ion-implanted ZnO thin films by ion implantation into sputtered ZnO thin films on a glass substrate. An investigation of the effects of ion doses and activation time on the electrical and optical properties of the films has been made. The electrical sheet resistance and resistivity of the implanted films are observed to increase with increasing rapid thermal annealing (RTA) time, while decreasing as the ion dose increases. Without any RTA process, the variation of the carrier density is insensitive to the ion dose. With the RTA process, however, the carrier density of the implanted films increases and approaches that of the un-implanted ZnO film as the ion dose increases. On the other hand, the carrier mobility is shown to decrease with increasing ion doses when no RTA process is applied. With the RTA process, however, there is almost no change in the mobility. We have achieved the optical transmittance as high as 87% within the visible wavelength range up to 800 nm. It is also demonstrated that the work function can be engineered by changing the ion dose during the ion implantation process. We have found that the work function decreases as the ion dose increases.

  15. A simple ion implanter for material modifications in agriculture and gemmology

    NASA Astrophysics Data System (ADS)

    Singkarat, S.; Wijaikhum, A.; Suwannakachorn, D.; Tippawan, U.; Intarasiri, S.; Bootkul, D.; Phanchaisri, B.; Techarung, J.; Rhodes, M. W.; Suwankosum, R.; Rattanarin, S.; Yu, L. D.

    2015-12-01

    In our efforts in developing ion beam technology for novel applications in biology and gemmology, an economic simple compact ion implanter especially for the purpose was constructed. The designing of the machine was aimed at providing our users with a simple, economic, user friendly, convenient and easily operateable ion implanter for ion implantation of biological living materials and gemstones for biotechnological applications and modification of gemstones, which would eventually contribute to the national agriculture, biomedicine and gem-industry developments. The machine was in a vertical setup so that the samples could be placed horizontally and even without fixing; in a non-mass-analyzing ion implanter style using mixed molecular and atomic nitrogen (N) ions so that material modifications could be more effective; equipped with a focusing/defocusing lens and an X-Y beam scanner so that a broad beam could be possible; and also equipped with a relatively small target chamber so that living biological samples could survive from the vacuum period during ion implantation. To save equipment materials and costs, most of the components of the machine were taken from decommissioned ion beam facilities. The maximum accelerating voltage of the accelerator was 100 kV, ideally necessary for crop mutation induction and gem modification by ion beams from our experience. N-ion implantation of local rice seeds and cut gemstones was carried out. Various phenotype changes of grown rice from the ion-implanted seeds and improvements in gemmological quality of the ion-bombarded gemstones were observed. The success in development of such a low-cost and simple-structured ion implanter provides developing countries with a model of utilizing our limited resources to develop novel accelerator-based technologies and applications.

  16. 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.

  17. Effect of Ar Ion Beam Implantation on Morphological and Physiological Characteristics of Liquorice (Glycyrrhiza uralensis Fisch) Under Short-Term Artificial Drought Conditions

    NASA Astrophysics Data System (ADS)

    Zhang, Xiangsheng; Wu, Lijun; Yu, Lixiang; Wei, Shenglin; Liu, Jingnan; Yu, Zengliang

    2007-04-01

    Ar+ ion beam with low energy of 30 keV was implanted into liquorice (Glycyrrhiza uralensis Fisch) seeds at the doses of 0, 600, 900 and 1200 × (2.6 × 1013) ions/cm2, respectively. The seeds were sowed in pots and after one month the plants were subjected to different drought conditions for two months. Then the plants' morphological and physiological characteristics, anti-oxidation enzymes and levels of endogenous hormones were investigated. The results showed that ion implantation at a proper dose can greatly enhance the liquorice seedlings' resistance against drought stress.

  18. 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.

  19. Surface engineering of a Zr-based bulk metallic glass with low energy Ar- or Ca-ion implantation.

    PubMed

    Huang, Lu; Zhu, Chao; Muntele, Claudiu I; Zhang, Tao; Liaw, Peter K; He, Wei

    2015-02-01

    In the present study, low energy ion implantation was employed to engineer the surface of a Zr-based bulk metallic glass (BMG), aiming at improving the biocompatibility and imparting bioactivity to the surface. Ca- or Ar-ions were implanted at 10 or 50 keV at a fluence of 8 × 10(15)ions/cm(2) to (Zr0.55Al0.10Ni0.05Cu0.30)99Y1 (at.%) BMG. The effects of ion implantation on material properties and subsequent cellular responses were investigated. Both Ar- and Ca-ion implantations were suggested to induce atom displacements on the surfaces according to the Monte-Carlo simulation. The change of atomic environment of Zr in the surface regions as implied by the alteration in X-ray absorption measurements at Zr K-edge. X-ray photoelectron spectroscopy revealed that the ion implantation process has modified the surface chemical compositions and indicated the presence of Ca after Ca-ion implantation. The surface nanohardness has been enhanced by implantation of either ion species, with Ca-ion implantation showing more prominent effect. The BMG surfaces were altered to be more hydrophobic after ion implantation, which can be attributed to the reduced amount of hydroxyl groups on the implanted surfaces. Higher numbers of adherent cells were found on Ar- and Ca-ion implanted samples, while more pronounced cell adhesion was observed on Ca-ion implanted substrates. The low energy ion implantation resulted in concurrent modifications in atomic structure, nanohardness, surface chemistry, hydrophobicity, and cell behavior on the surface of the Zr-based BMG, which were proposed to be mutually correlated with each other. Published by Elsevier B.V.

  20. Wear resistance of highly cross-linked and remelted polyethylenes after ion implantation and accelerated ageing.

    PubMed

    Medel, F J; Puértolas, J A

    2008-08-01

    Ion implantation may provide medical polyethylenes with excellent mechanical and tribological properties, helping to lower the risk of long-term osteolysis. Highly crosslinked and remelted polyethylenes, materials currently used as soft components in artificial joints, were implanted with N+ and He+ ions at different ion fluences. The mechanical and tribological properties under distilled water lubrication at body temperature were assessed after ion implantation by means of microhardness and pin-on-disc tests respectively. Thus, the influences of the ionic species and implantation dose on surface hardness, friction coefficient, and wear factor were fully characterized. Furthermore, the tribological behaviour was evaluated after an accelerated ageing protocol (120 degrees C for 36h). Ion implantation increased the surface hardness, as well as friction coefficients, and decreased the wear factors especially at the highest doses. Also, even though all artificially aged materials showed a worse wear behaviour, polyethylenes implanted with either N+ or He+ at the highest doses maintained a relatively good wear factor in comparison with the aged non-implanted material. The origins of these modifications are discussed according to the effects of ion implantation on the microstructure of the polymer.

  1. Ion implantation reduces radiation sensitivity of metal oxide silicon /MOS/ devices

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Implanting nitrogen ions improves hardening of silicon oxides 30 percent to 60 percent against ionizing radiation effects. Process reduces sensitivity, but retains stability normally shown by interfaces between silicon and thermally grown oxides.

  2. Ion-implanted PLZT ceramics: a new high-sensitivity image storage medium

    SciTech Connect

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

    1980-01-01

    Results were presented of our studies of photoferroelectric (PFE) image storage in H- and He-ion implanted PLZT (lead lanthanum zirconate titanate) ceramics which demonstrate that the photosensitivity of PLZT can be significantly increased by ion implantation in the ceramic surface to be exposed to image light. More recently, implantations of Ar and Ar + Ne into the PLZT surface have produced much greater photosensitivity enhancement. For example, the photosensitivity after implantation with 1.5 x 10/sup 14/ 350 keV Ar/cm/sup 2/ + 1 x 10/sup 15/ 500 keV Ne/cm/sup 2/ is increased by about four orders of magnitude over that of unimplanted PLZT. Measurements indicate that the photosensitivity enhancement in ion-implanted PLZT is controlled by implantation-produced disorder which results in marked decreases in dielectric constant and dark conductivity and changes in photoconductivity of the implanted layer. The effects of Ar- and Ar + Ne-implantation are presented along with a phenomenological model which describes the enhancement in photosensitivity obtained by ion implantation. This model takes into account both light- and implantation-induced changes in conductivity and gives quantitative agreement with the measured changes in the coercive voltage V/sub c/ as a function of near-uv light intensity for both unimplanted and implanted PLZT. The model, used in conjunction with calculations of the profiles of implantation-produced disorder, has provided the information needed for co-implanting ions of different masses, e.g., Ar and Ne, to improve photosensitivity.

  3. 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.

  4. 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.

  5. New optical properties of MgO after MeV metal ion implantation

    NASA Astrophysics Data System (ADS)

    Zimmerman, R. L.; Ila, D.; Williams, E. K.; Sarkisov, S. S.; Poker, D. B.; Hensley, D. K.

    1999-06-01

    The implantation of metal ions into single crystals of MgO(100) followed by thermal annealing leads to an increase in absorption of ultra violet and visible light. Metal ions of Au, Sn, Ag, Cu and Ti were implanted at a depth of a few thousand Angstroms followed by thermal annealing. MgO samples implanted with He and Si ions at greater depths were used to study the optical effects and thermal annealing of radiation damage. The influence of bombardment fluence and heat treatment on the size of the metal clusters and on the fraction of atoms in clusters were measured using absorption photospectrometry.

  6. Interferometric pump-probe characterization of the nonlocal response of optically transparent ion implanted polymers

    NASA Astrophysics Data System (ADS)

    Stefanov, Ivan L.; Hadjichristov, Georgi B.

    2012-03-01

    Optical interferometric technique is applied to characterize the nonlocal response of optically transparent ion implanted polymers. The thermal nonlinearity of the ion-modified material in the near-surface region is induced by continuous wave (cw) laser irradiation at a relatively low intensity. The interferometry approach is demonstrated for a subsurface layer of a thickness of about 100 nm formed in bulk polymethylmethacrylate (PMMA) by implantation with silicon ions at an energy of 50 keV and fluence in the range 1014-1017 cm-2. The laser-induced thermooptic effect in this layer is finely probed by interferometric imaging. The interference phase distribution in the plane of the ion implanted layer is indicative for the thermal nonlinearity of the near-surface region of ion implanted optically transparent polymeric materials.

  7. Work function increase of Al-doped ZnO thin films by B+ ion implantation.

    PubMed

    Hong, Sang-Jin; Heo, Gi-Seok; Park, Jong-Woon; Lee, In-Hwan; Choi, Bum-Ho; Lee, Jong-Ho; Park, Se-Yeon; Shin, Dong-Chan

    2007-11-01

    The work function of an Al-doped ZnO (AZO) thin film can be increased via B+ ion implantation from 3.92 eV up to 4.22 eV. The ion implantation has been carried out with the ion dose of 1 x 10(16) cm(-2) and ion energy of 5 keV. The resistance of the B+ implanted AZO films has been a bit raised, while their transmittance is slightly lowered, compared to those of un-implanted AZO films. These behaviors can be explained by the doping profile and the resultant band diagram. It is concluded that the coupling between the B+ ions and oxygen vacancies would be the main reason for an increase in the work function and a change in the other properties. We also address that the work function is more effectively alterable if the defect density of the top transparent conducting oxide layer can be controlled.

  8. 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.

  9. 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.

  10. Ion-implanted PLZT ceramics - A new high-sensitivity image storage medium

    NASA Astrophysics Data System (ADS)

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

    1981-06-01

    Studies of photoferroelectric (PFE) image storage in H, He, and Ar, and more recently, Ar + Ne implanted PLZT reveal that the photosensitivity can be significantly increased by ion implantation into the image storage surface. For example, the photosensitivity after coimplantation of Ar + Ne is increased by about four orders of magnitude over that of unimplanted PLZT. The increase in photosensitivity is controlled by implantation-produced disorder which results in marked decreases in dark conductivity and dielectric constant and changes in the effective photoconductivity of the implanted layer. In this paper the effects of Ar and Ar + Ne implantation are presented along with a phenomenological model which describes the photosensitivity enhancement obtained by ion implantation.

  11. 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.

  12. 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.

  13. Achieving low parasitic resistance in Ge p-channel metal-oxide-semiconductor field-effect transistors by ion implantation after germanidation

    NASA Astrophysics Data System (ADS)

    Hsin Chang, Wen; Ota, Hiroyuki; Maeda, Tatsuro

    2015-05-01

    The parasitic resistance (Rpara) of Ge p-channel metal-oxide-semiconductor field-effect transistors (p-MOSFETs) fabricated by ion implantation after germanidation (IAG) has been investigated by varying the drive-in annealing temperature. The lowest Rpara of 835 Ω µm was achieved after 450 °C drive-in annealing for 1 min. Boron segregation between NiGe and Ge induced by drive-in annealing has advantages in forming an abrupt metallic source/drain (S/D) junction and contributes to the decrease in Rpara. The appropriate process window for fabricating Ge p-MOSFETs by IAG was also given. IAG, a pathway for introducing a Ge channel into CMOS technology beyond the 10 nm node, was proved to be effective for reducing Rpara.

  14. 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.

  15. Effects of gold coating on experimental implant fixation

    PubMed Central

    Zainali, Kasra; Danscher, Gorm; Jakobsen, Thomas; Jakobsen, Stig S.; Baas, Jørgen; Møller, Per; Bechtold, Joan E.; Soballe, Kjeld

    2013-01-01

    Insertions of orthopedic implants are traumatic procedures that trigger an inflammatory response. Macrophages have been shown to liberate gold ions from metallic gold. Gold ions are known to act in an antiinflammatory manner by inhibiting cellular NF-κB–DNA binding and suppressing I-κ B-kinase activation. The present study investigated whether gilding implant surfaces augmented early implant osseointegration and implant fixation by its modulatory effect on the local inflammatory response. Ion release was traced by autometallographic silver enhancement. Gold-coated cylindrical porous coated Ti6Al4V implants were inserted press-fit in the proximal part of tibiae in nine canines and control implants without gold inserted contralateral. Observation time was 4 weeks. Biomechanical push-out tests showed that implants with gold coating had ~50% decrease in mechanical strength and stiffness. Histomorphometrical analyses showed gold-coated implants had a decrease in overall total bone-to-implant contact of 35%. Autometallographic analysis revealed few cells loaded with gold close to the gilded implant surface. The findings demonstrate that gilding of implants negatively affects mechanical strength and osseointegration because of a significant effect of the released gold ions on the local inflammatory process around the implant. The possibility that a partial metallic gold coating could prolong the period of satisfactory mechanical strength, however, cannot be excluded. PMID:18335533

  16. Characterization of high energy ion implantation into Ti-6Al-4V

    NASA Astrophysics Data System (ADS)

    Carroll, M. P.; Stephenson, K.; Findley, K. O.

    2009-06-01

    Ion implantation is a surface modification process that can improve the wear, fatigue, and corrosion resistance for several metals and alloys. Much of the research to date has focused on ion energies less than 1 MeV. With this in mind, Ti-6Al-4V was implanted with Al 2+, Au 3+, and N + ions at energies of 1.5 and 5 MeV and various doses to determine the effects on strengthening of a high energy beam. A post heat treatment on the specimens implanted with Al 2+ samples was conducted to precipitate Ti xAl type intermetallics near the surface. Novel techniques, such as nanoindentation, are available now to determine structure-mechanical property relationships in near-surface regions of the implanted samples. Thus, nanoindentation was performed on pre-implanted, as-implanted, and post heat treated samples to detect differences in elastic modulus and hardness at the sub-micron scale. In addition, sliding wear tests were performed to qualitatively determine the changes in wear performance. The effect of this processing was significant for samples implanted with Al 2+ ions at 1.5 MeV with a dose higher than 1 × 10 16 ions/cm 2 where precipitation hardening likely occurs and with N + ions.

  17. Lateral Magnetically Modulated Multilayers by Combining Ion Implantation and Lithography.

    PubMed

    Menéndez, Enric; Modarresi, Hiwa; Petermann, Claire; Nogués, Josep; Domingo, Neus; Liu, Haoliang; Kirby, Brian J; Mohd, Amir Syed; Salhi, Zahir; Babcock, Earl; Mattauch, Stefan; Van Haesendonck, Chris; Vantomme, André; Temst, Kristiaan

    2017-03-01

    The combination of lithography and ion implantation is demonstrated to be a suitable method to prepare lateral multilayers. A laterally, compositionally, and magnetically modulated microscale pattern consisting of alternating Co (1.6 µm wide) and Co-CoO (2.4 µm wide) lines has been obtained by oxygen ion implantation into a lithographically masked Au-sandwiched Co thin film. Magnetoresistance along the lines (i.e., current and applied magnetic field are parallel to the lines) reveals an effective positive giant magnetoresistance (GMR) behavior at room temperature. Conversely, anisotropic magnetoresistance and GMR contributions are distinguished at low temperature (i.e., 10 K) since the O-implanted areas become exchange coupled. This planar GMR is principally ascribed to the spatial modulation of coercivity in a spring-magnet-type configuration, which results in 180° Néel extrinsic domain walls at the Co/Co-CoO interfaces. The versatility, in terms of pattern size, morphology, and composition adjustment, of this method offers a unique route to fabricate planar systems for, among others, spintronic research and applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Ion-implanted epitaxially grown ZnSe

    NASA Technical Reports Server (NTRS)

    Chernow, F.

    1975-01-01

    The use of ZnSe to obtain efficient, short wavelength injection luminescence was investigated. It was proposed that shorter wavelength emission and higher efficiency be achieved by employing a p-i-n diode structure rather than the normal p-n diode structure. The intervening i layer minimizes concentration quenching effects and the donor-acceptor pair states leading to long wavelength emission. The surface p layer was formed by ion implantation; implantation of the i layer rather than the n substrate permits higher, uncompensated p-type doping. An ion implanted p-n junction in ZnSe is efficiency-limited by high electron injection terminating in nonradiative recombination at the front surface, and by low hole injection resulting from the inability to obtain high conductivity p-type surface layers. While the injection ratio in p-n junctions was determined by the radio of majority carrier concentrations, the injection ratio in p-i-n structures was determined by the mobility ratios and/or space charge neutrality requirements in the i layer.

  19. Scanning-electron-microscopy observations and mechanical characteristics of ion-beam-sputtered surgical implant alloys

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Meyer, M. L.; Ling, J. S.

    1977-01-01

    An electron bombardment ion thruster was used as an ion source to sputter the surfaces of orthopedic prosthetic metals. Scanning electron microscopy photomicrographs were made of each ion beam textured surface. The effect of ion texturing an implant surface on its bond to bone cement was investigated. A Co-Cr-W alloy and surgical stainless steel were used as representative hard tissue implant materials to determine effects of ion texturing on bulk mechanical properties. Work was done to determine the effect of substrate temperature on the development of an ion textured surface microstructure. Results indicate that the ultimate strength of the bulk materials is unchanged by ion texturing and that the microstructure will develop more rapidly if the substrate is heated prior to ion texturing.

  20. 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.

  1. Use of low-energy hydrogen ion implants in high-efficiency crystalline-silicon solar cells

    NASA Technical Reports Server (NTRS)

    Fonash, S. J.; Sigh, R.; Mu, H. C.

    1986-01-01

    The use of low-energy hydrogen implants in the fabrication of high-efficiency crystalline silicon solar cells was investigated. Low-energy hydrogen implants result in hydrogen-caused effects in all three regions of a solar cell: emitter, space charge region, and base. In web, Czochralski (Cz), and floating zone (Fz) material, low-energy hydrogen implants reduced surface recombination velocity. In all three, the implants passivated the space charge region recombination centers. It was established that hydrogen implants can alter the diffusion properties of ion-implanted boron in silicon, but not ion-implated arsenic.

  2. Comparison of monomode KTiOPO4 waveguide formed by C3+ ion implantation and Rb+ ion exchange

    NASA Astrophysics Data System (ADS)

    Cui, Xiao-Jun; Wang, Liang-Ling

    2017-02-01

    In this work, we report on the formation and characterization of monomode KTiOPO4 waveguide at 1539 nm by 6.0 MeV C3+ ion implantation with the dose of 2×1015 ions/cm2 and Rb+-K+ ion exchange, respectively. The relative intensity of light as a function of effective refractive index of TM modes at 633 nm and 1539 nm for KTiOPO4 waveguide formed by two different methods were compared with the prism coupling technique. The refractive index (nz) profile for the ion implanted waveguide was reconstructed by reflectivity calculation method, and one for the ion exchanged waveguide was by inverse Wentzel-Kramers-Brillouin. The nuclear energy loss versus penetration depth of the C3+ ions implantation into KTiOPO4 was simulated using the Stopping Range of Ions in Matter software. The Rutherford Backscattering Spectrometry spectrum of KTiOPO4 waveguide was analyzed after ions exchanged. The results showed that monomode waveguide at 1539 nm can be formed by ion implantation and Rb+ -K+ ion exchange, respectively.

  3. Electron spin resonance study of ion-implanted polymers

    NASA Astrophysics Data System (ADS)

    Wasserman, B.; Dresselhaus, M. S.; Braunstein, G.; Wnek, G. E.; Roth, G.

    1985-03-01

    The effect of ion implantation on the polymers PAN (polyacrylonitrile), PPO (poly 2,6-dimethylphenylene oxide) and PPS (p-polyphenylene sulfide) is studied using electron spin resonance. ESR measurements on these polymers were performed as a function of ion species and fluence in the temperature range 10 ion species used for implantation in this study (84Kr,80Br,75As,40Ar and14N). It is therefore concluded that the carrier concentration is related to the structural damage and not to chemical doping effects. From the shape of the ESR line, the ratio of the relaxation times for one-dimensional to three-dimensional spin diffusion is determined to be larger than 1000. The temperature dependence of the unpaired carrier concentration shows a strong deviation from a Curie law behavior, which can be explained by assuming that a defect band is formed with a bandgap due to strong Coulomb interaction between electrons on the defect sites.

  4. 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.

  5. 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.

  6. A study of the factors which control the efficiency of ion-implanted silicon solar cells

    NASA Technical Reports Server (NTRS)

    Douglas, E. C.; Daiello, R. V.

    1980-01-01

    The objective of this work was to determine experimentally the ion-implantation parameters and furnace annealing conditions required to produce high-efficiency solar cells. A comprehensive experimental study was conducted in which the optimum ion-implantation parameters were found by a systematic variation of the implant parameters followed by detailed studies of solar-cell devices. Two furnace heat-treatment techniques were found which effectively anneal the implanted layers and at the same time preserve or improve the diffusion length in the bulk silicon. Detailed characteristics of both the junction and bulk properties of solar cells fabricated over the spectrum of implant parameters are discussed. Optimized implant parameters and annealing conditions were found which allow for the fabrication of 14-15-percent (AM1) efficient solar cells.

  7. 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.

  8. 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.

  9. 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.

  10. Ion Implantation in III-V Compound Semiconductors

    DTIC Science & Technology

    1984-09-01

    340 keV H + -0 Ga P  O UES-723-292 !:• (H o>ray *P-K X - rayO Ga-K X -ray iii! RBS * ..I -iO.. 0 10I to1. 01 • .0 -. I0 1 LI =i, O I 0 01 0.J 10...Identity by blo ," pume) Ion Implantation, GaAs, Hall effect, electrical resistivity, Rutherford Backscattering (RBS), channeling, Proton induced x -ray...Mebility (jH) upon Aiinealing Temperature (TA) for 1 X 101 /cm• Dose Samples of GaAs:Mg with Three Different Capping Methods 33 p 14 Dependence of Surface

  11. 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

  12. 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

  13. 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

  14. Antibacterial PVD coatings doped with silver by ion implantation

    NASA Astrophysics Data System (ADS)

    Osés, J.; Palacio, J. F.; Kulkarni, S.; Medrano, A.; García, J. A.; Rodríguez, R.

    2014-08-01

    The antibacterial effect of certain metal ions, like silver, has been exploited since antiquity. Obviously, the ways to employ the biocide activity of this element have evolved throughout time and it is currently used in a wide range of clinical applications. The work presented here reports the results of an investigation focused on combining the protective properties of PVD coatings with the biocide property of silver, applied by ion implantation. For this purpose, chromium nitride layers were doped with silver implanted at two different doses (5 × 1016 and 1 × 1017 ion/cm2) at 100 keV of energy and perpendicular incidence. Full characterization of the coatings was performed to determine its topographical and mechanical properties. The concentration profile of Ag was analyzed by GD-OES. The thickness of the layers, nano-hardness, roughness, wear resistance and coefficient of friction were measured. Finally, the anti-bacterial efficacy of the coatings was determined following the JIS Z-2801:2010 Standard. The results provide clear insights into the efficacy of silver for antibacterial purposes, as well as on its influence in the mechanical and tribological behaviour of the coatings matrix.

  15. Effects of N{sub 2}{sup +} ion implantation on phase transition in Ge{sub 2}Sb{sub 2}Te{sub 5} films

    SciTech Connect

    Kim, Young Kuk; Baeck, J. H.; Cho, M.-H.; Jeong, E. J.; Ko, D.-H.

    2006-10-15

    The phase transitions of Ge{sub 2}Sb{sub 2}Te{sub 5} (GST) films after bombardment with 40 keV N{sub 2}{sup +} ions were investigated. Comparing the nitrogen incorporated GST films with a pure GST film, the suppression of a crystalline grain growth was more effective in the N{sub 2}{sup +} implanted GST film than in a nitrogen codeposited GST film, i.e., x-ray diffraction data showed that the intensities of the crystalline diffraction peaks were decreased and the full widths at half maximum were broader than that of a pure GST film. This suppression of crystallization owing to the incorporation of nitrogen drastically reduced the roughness of surface morphology and decreased the electrical conductivity of the crystalline film. A near edge x-ray absorption fine structure experiment and x-ray photoemission spectroscopy data demonstrated that the suppression of crystalline grain growth is due to the formation of Ge{sub 3}N{sub 4} and interstitial N{sub 2} molecules. In N{sub 2}{sup +} implanted GST films, in particular, interstitial N{sub 2} molecules played a major role in the suppression of crystallization.

  16. Wafer-scale synthesis of multi-layer graphene by high-temperature carbon ion implantation

    NASA Astrophysics Data System (ADS)

    Kim, Janghyuk; Lee, Geonyeop; Kim, Jihyun

    2015-07-01

    We report on the synthesis of wafer-scale (4 in. in diameter) high-quality multi-layer graphene using high-temperature carbon ion implantation on thin Ni films on a substrate of SiO2/Si. Carbon ions were bombarded at 20 keV and a dose of 1 × 1015 cm-2 onto the surface of the Ni/SiO2/Si substrate at a temperature of 500 °C. This was followed by high-temperature activation annealing (600-900 °C) to form a sp2-bonded honeycomb structure. The effects of post-implantation activation annealing conditions were systematically investigated by micro-Raman spectroscopy and transmission electron microscopy. Carbon ion implantation at elevated temperatures allowed a lower activation annealing temperature for fabricating large-area graphene. Our results indicate that carbon-ion implantation provides a facile and direct route for integrating graphene with Si microelectronics.

  17. Improved thermostable α-amylase activity of Bacillus amyloliquefaciens by low-energy ion implantation.

    PubMed

    Li, X Y; Zhang, J L; Zhu, S W

    2011-09-23

    Thermostable α-amylase is of great importance in the starch fermentation industry; it is extensively used in the manufacture of beverages, baby foods, medicines, and pharmaceuticals. Bacillus amyloliquefaciens produces thermostable α-amylase; however, production of thermostable α-amylase is limited. Ion-beam implantation is an effective method for mutation breeding in microbes. We conducted ion-beam implantation experiments using two different ions, Ar(+) and N(+), to determine the survival rate of and dose effect on a high α-amylase activity strain of B. amyloliquefaciens that had been isolated from soil samples. N(+) implantation resulted in a higher survival rate than Ar(+) implantation. The optimum implantation dose was 2.08 × 10(15) ions/cm(2). Under this implantation condition, we obtained a thermally and genetically stable mutant α-amylase strain (RL-1) with high enzyme activity for degrading α-amylase. Compared to the parental strain (RL), the RL-1 strain had a 57.1% increase in α-amylase activity. We conclude that ion implantation in B. amyloliquefaciens can produce strains with increased production of thermostable α-amylase.

  18. 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.

  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. 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.

  1. A novel approach to microbial breeding--low-energy ion implantation.

    PubMed

    Gu, Shao-Bin; Li, Shi-Chang; Feng, Hui-Yun; Wu, Ying; Yu, Zeng-Liang

    2008-02-01

    Low-energy ions exist widely in the natural world. People had neglected the interaction between low-energy ions and material; it was even more out of the question to study the relation of low-energy ions and the complicated organism until the biological effects of low-energy ion implantation were discovered in 1989. Nowadays, the value of low-energy ion beam implantation, as a new breeding way, has drawn extensive attention of biologists and breeding experts. In this review, the understanding and utilization of microbial breeding by low-energy ion beam irradiation is summarized, including the characteristics of an ion beam bioengineering facility, present status of the technology of low-energy ions for microbial breeding, and new insights into microbial biotechnology.

  2. Enhancing antibacterial properties of UHMWPE via ion implantation

    NASA Astrophysics Data System (ADS)

    Nassisi, Vincenzo; Delle Side, Domenico; Velardi, Luciano; Alifano, Pietro; Talà, Adelfia; Maurizio Tredici, Salvatore

    2012-10-01

    In the last decades, the demand for biomaterials of antimicrobial quality sensibly increased. The essential properties of these materials must be the biocompatibility, wettability, durability and their antibacterial characteristics. One of the most important biomaterial for medical applications is the ultra high molecular weight polyethylene (UHMWPE) that it is used to make components of prosthetic knee, hip and shoulder. It is well known that the presence in UHMWPE of Ag atoms increase its antibacterial properties while Cu and its alloys are known as natural antimicrobial materials. In this work it is proposed a dedicated laser ion source (LIS) accelerator to perform ion implantation together with a systematic study of the surface properties of UHMWPE samples treated with different metals in order to modify their antibacterial characteristics. The proposed technique consists in the application of a dose of specific ions inside the first layer of the sample to be treated. This goal can be effectively achieved if the ions are preventively accelerated. This technique seems to be interesting, since it can open the way to an easier realization of antibacterial materials using various metal ions.

  3. Ferromagnetic GeMn thin film prepared by ion implantation and ion beam induced epitaxial crystallization annealing

    NASA Astrophysics Data System (ADS)

    Chen, C. H.; Niu, H.; Yan, D. C.; Hsieh, H. H.; Lee, C. P.; Chi, C. C.

    2012-06-01

    Ferromagnetic GeMn was prepared by Mn implantation followed by ion beam-induced epitaxial crystallization annealing. The damage caused by Mn implantation was repaired by subsequent helium ion irradiation. Various structural analyses were performed and Mn ions were found to incorporate uniformly into the Ge lattice without the formation of any secondary phases. The remnant magnetic moment exhibited room temperature ferromagnetism. Anomalous Hall effect and field dependent magnetization were measured at the same time at room temperature indicating spin polarized free carrier transport. Additional measurement using x-ray magnetic circular dichroism also revealed that the carriers were spin-polarized.

  4. 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.

  5. 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.

  6. Deformation characteristics of the near-surface layers of zirconia ceramics implanted with aluminum ions

    NASA Astrophysics Data System (ADS)

    Ghyngazov, S. A.; Vasiliev, I. P.; Frangulyan, T. S.; Chernyavski, A. V.

    2015-10-01

    The effect of ion treatment on the phase composition and mechanical properties of the near-surface layers of zirconium ceramic composition 97 ZrO2-3Y2O3 (mol%) was studied. Irradiation of the samples was carried out by accelerated ions of aluminum with using vacuum-arc source Mevva 5-Ru. Ion beam had the following parameters: the energy of the accelerated ions E = 78 keV, the pulse current density Ji = 4mA / cm2, current pulse duration equal τ = 250 mcs, pulse repetition frequency f = 5 Hz. Exposure doses (fluence) were 1016 и 1017 ion/cm2. The depth distribution implanted ions was studied by SIMS method. It is shown that the maximum projected range of the implanted ions is equal to 250 nm. Near-surface layers were investigated by X-ray diffraction (XRD) at fixed glancing incidence angle. It is shown that implantation of aluminum ions into the ceramics does not lead to a change in the phase composition of the near-surface layer. The influence of implanted ions on mechanical properties of ceramic near-surface layers was studied by the method of dynamic nanoindentation using small loads on the indenter P=300 mN. It is shown that in ion- implanted ceramic layer the processes of material recovery in the deformed region in the unloading mode proceeds with higher efficiency as compared with the initial material state. The deformation characteristics of samples before and after ion treatment have been determined from interpretation of the resulting P-h curves within the loading and unloading sections by the technique proposed by Oliver and Pharr. It was found that implantation of aluminum ions in the near-surface layer of zirconia ceramics increases nanohardness and reduces the Young's modulus.

  7. 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)

  8. Effects of helium ion implantation on the surface morphology of tungsten at high temperature for the first wall armor and divertor plates of fusion reactors

    NASA Astrophysics Data System (ADS)

    Zenobia, Samuel J.

    Three devices at the University of Wisconsin-Madison Inertial Electrostatic Confinement (UW IEC) laboratory were used to implant W and W alloys with helium ions at high temperatures. These devices were HOMER, HELIOS, and the Materials Irradiation Experiment (MITE-E). The research presented in this thesis will focus on the experiments carried out utilizing the MITE-E. Early UW work in HOMER and HELIOS on silicon carbide, carbon velvet, W-coated carbon velvet, fine-grain W, nano-grain W, W needles, and single- and polycrystalline W showed that these materials were not resistant to He+ implantation above ˜800 °C. Unalloyed W developed a "coral-like" surface morphology after He+ implantation, but appeared to be the most robust material investigated. The MITE-E used an ion gun technology to implant tungsten with 30 keV He+. Tungsten specimens were implanted at 900 °C to total average fluences of 6x1016 -- 6x1018 He +/cm2. Other specimens were implanted to a total average fluence of 5x1018 He+/cm2 at temperatures between 500 and 900 °C. Micrographs of the implanted W specimens revealed the development of three distinct surface morphologies. These morphologies are classified as "blistering", "pitting", and "orientated ridges". Preferential sputtering of the W by the energetic He+ appears to be responsible for pitting and orientated ridges which developed at high fluences (1019 He+/cm2) in the MITE-E. While the orientated ridges were the dominant morphology on the W surface above 700 °C, the pitting was prevalent below 700 °C. The blister morphology was observed at all of the examined temperatures at fluences ≥5x1017 He+/cm2 but disappeared above fluences of 1019 He+/cm 2. The "coral-like" surface morphology on W inherent to He + implantation experiments in HOMER and HELIOS developed from a combination of sources: multiangular ion incidence, ion energy spread (softening), and electron field emission from nano-scale surface features induced by He + implantation. The

  9. 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.

  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. Decrease of Staphylococcal adhesion on surgical stainless steel after Si ion implantation

    NASA Astrophysics Data System (ADS)

    Braceras, Iñigo; Pacha-Olivenza, Miguel A.; Calzado-Martín, Alicia; Multigner, Marta; Vera, Carolina; Broncano, Luis Labajos-; Gallardo-Moreno, Amparo M.; González-Carrasco, José Luis; Vilaboa, Nuria; González-Martín, M. Luisa

    2014-08-01

    316LVM austenitic stainless steel is often the material of choice on temporal musculoskeletal implants and surgical tools as it combines good mechanical properties and acceptable corrosion resistance to the physiologic media, being additionally relatively inexpensive. This study has aimed at improving the resistance to bacterial colonization of this surgical stainless steel, without compromising its biocompatibility and resistance. To achieve this aim, the effect of Si ion implantation on 316LVM has been studied. First, the effect of the ion implantation parameters (50 keV; fluence: 2.5-5 × 1016 ions/cm2; angle of incidence: 45-90°) has been assessed in terms of depth profiling of chemical composition by XPS and nano-topography evaluation by AFM. The in vitro biocompatibility of the alloy has been evaluated with human mesenchymal stem cells. Finally, bacterial adhesion of Staphylococcus epidermidis and Staphylococcus aureus on these surfaces has been assessed. Reduction of bacterial adhesion on Si implanted 316LVM is dependent on the implantation conditions as well as the features of the bacterial strains, offering a promising implantable biomaterial in terms of biocompatibility, mechanical properties and resistance to bacterial colonization. The effects of surface composition and nano-topography on bacterial adhesion, directly related to ion implantation conditions, are also discussed.

  13. 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.

  14. Implant marketing: cost effective implant dentistry.

    PubMed

    Wohrle, P S; Levin, R P

    1996-01-01

    The application of the KAL-Technique to the field of implant dentistry allows both patients and dental practices to benefit. It is an exciting advance that decreases frustration and stress in providing implant procedures and lowers overall costs. Professionals using the KAL-Technique report significant predictability in achieving passive framework fit. They are also lowering overall cost of implant cases, which increases the number of patients who can accept implant treatment. It has been well established that the more individuals in a practice that receive implants, the more referrals a practice will gain. This is because implant patients find tremendous advances in the quality of life, and do not hesitate to tell others who can take advantage of this opportunity. Implant dentistry is one of the fastest growing fields in dentistry today. While some other areas of dentistry begin to decline in volume and need, implant dentistry provides the opportunity to keep practices strong and to insure long-term success.

  15. Ion Implantation of In0.53Ga0.47As

    SciTech Connect

    Almonte, Marlene Isabel

    1999-05-01

    Studies of the effects of implanation in In0.53Ga0.47As due to damage by implantation of Ne+ ions and to compensation by implantation of Fe+ ions are reported in this thesis.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. Critical problems of ion implantation in processing small geometry integrated devices

    NASA Astrophysics Data System (ADS)

    Tokuyama, Takashi

    1989-02-01

    A brief review is described on the critical problems of ion implantation in processing small geometry integrated devices. The commonly recognized critical paths of the technology, i.e. formation of shallow junctions, impurity doping of vertical side walls, shadowing and the scattering effect of the incident beam are discussed based on recent data. Discussion is also given of the annealing behavior and residual defects of small and isolated implanted regions, and the considerable difference from those of the continuous implanted layers is shown. These problems are more or less related to the fundamental principles of implantation that impurities are doped by the incidence of energetic ions. Based on these facts, attempts are made to estimate the final size of the future devices to which implantation can be applied.

  1. Ion implantation for high performance III-V JFETS and HFETS

    SciTech Connect

    Zolper, J.C.; Baca, A.G.; Sherwin, M.E.; Klem, J.F.

    1996-06-01

    Ion implantation has been an enabling technology for realizing many high performance electronic devices in III-V semiconductor materials. We report on advances in ion implantation processing for GaAs JFETs (joint field effect transistors), AlGaAs/GaAs HFETs (heterostructure field effect transistors), and InGaP or InAlP-barrier HFETs. The GaAs JFET has required the development of shallow p-type implants using Zn or Cd with junction depths down to 35 nm after the activation anneal. Implant activation and ionization issues for AlGaAs are reported along with those for InGaP and InAlP. A comprehensive treatment of Si-implant doping of AlGaAs is given based on donor ionization energies and conduction band density-of-states dependence on Al-composition. Si and Si+P implants in InGaP are shown to achieve higher electron concentrations than for similar implants in AlGaAs due to absence of the deep donor level. An optimized P co- implantation scheme in InGaP is shown to increase the implanted donor saturation level by 65%.

  2. 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.

  3. Ion irradiation of 37Cl implanted nuclear graphite: Effect of the energy deposition on the chlorine behavior and consequences for the mobility of 36Cl in irradiated graphite

    NASA Astrophysics Data System (ADS)

    Toulhoat, N.; Moncoffre, N.; Bérerd, N.; Pipon, Y.; Blondel, A.; Galy, N.; Sainsot, P.; Rouzaud, J.-N.; Deldicque, D.

    2015-09-01

    Graphite is used in many types of nuclear reactors due to its ability to slow down fast neutrons without capturing them. Whatever the reactor design, the irradiated graphite waste management has to be faced sooner or later regarding the production of long lived or dose determining radioactive species such as 14C, 3H or 36Cl. The first carbon dioxide cooled, graphite moderated nuclear reactors resulted in a huge quantity of irradiated graphite waste for which the management needs a previous assessment of the radioactive inventory and the radionuclide's location and speciation. As the detection limits of usual spectroscopic methods are generally not adequate to detect the low concentration levels (<1 ppm) of the radionuclides, we used an indirect approach based on the implantation of 37Cl, to simulate the presence of 36Cl. Our previous studies show that temperature is one of the main factors to be considered regarding the structural evolution of nuclear graphite and chlorine mobility during reactor operation. However, thermal release of chlorine cannot be solely responsible for the depletion of the 36Cl inventory. We propose in this paper to study the impact of irradiation and its synergetic effects with temperature on chlorine release. Indeed, the collision of the impinging neutrons with the graphite matrix carbon atoms induces mainly ballistic collisions. However, a small part of the recoil carbon atom energy is also transferred to the lattice through electronic excitation. This paper aims at elucidating the effects of the different irradiation regimes (ballistic and electronic) using ion irradiation, on the mobility of implanted 37Cl, taking into account the initial disorder level of the nuclear graphite.

  4. Effect of Fe and Zr ion implantation and high-current electron irradiation treatment on chemical and mechanical properties of Ti-V-Al Alloy

    NASA Astrophysics Data System (ADS)

    Pogrebnjak, Alexander D.; Kobzev, Alexander P.; Gritsenko, Boris P.; Sokolov, Sergey; Bazyl, Elena; Sviridenko, Nikolai V.; Valyaev, Alexander N.; Ivanov, Yurii F.

    2000-03-01

    Using Rutherford backscattering spectroscopy, nuclear elastic resonance analysis, atomic force microscopy, transmission electron microscopy, and wear resistance and microhardness tests, the alloy Ti41-V41-Al18 was investigated after Fe ion (60 kV) and Zr (40 kV) ion implantation and subsequent high-current electron beam (HCEB) irradiation at an energy flow density of 6 J/cm2, called duplex treatment. Profiles show that the maximum concentration of Fe ions was 16.5 at. % at 85 nm from sample surface and that of Zr ions was 0.85 at. % at 56 nm. The maximum of the Fe concentration profile was found to shift to the large sample depth toward after increasing the implantation dose. The surface alloy layer is composed of a number of structures: grains of dislocation substructure (2×1010 cm-2), grains with plates, and grains with packed martensite. The disorientation of regions is observed. After HCEB treatment, the disorientation of microregions increases (Δα=7.5°) and particles of Ti2Fe are formed. After double implantation, the dry friction wear and the friction coefficient decreased. After the duplex treatment, the thickness of the hardened layer and the wear resistance increased.

  5. Suppression of ion-implantation induced porosity in germanium by a silicon dioxide capping layer

    NASA Astrophysics Data System (ADS)

    Tran, Tuan T.; Alkhaldi, Huda S.; Gandhi, Hemi H.; Pastor, David; Huston, Larissa Q.; Wong-Leung, Jennifer; Aziz, Michael J.; Williams, J. S.

    2016-08-01

    Ion implantation with high ion fluences is indispensable for successful use of germanium (Ge) in the next generation of electronic and photonic devices. However, Ge readily becomes porous after a moderate fluence implant ( ˜1 ×1015 ion cm-2 ) at room temperature, and for heavy ion species such as tin (Sn), holding the target at liquid nitrogen (LN2) temperature suppresses porosity formation only up to a fluence of 2 ×1016 ion cm-2 . We show, using stylus profilometry and electron microscopy, that a nanometer scale capping layer of silicon dioxide significantly suppresses the development of the porous structure in Ge during a S n - implant at a fluence of 4.5 ×1016 ion cm-2 at LN2 temperature. The significant loss of the implanted species through sputtering is also suppressed. The effectiveness of the capping layer in preventing porosity, as well as suppressing sputter removal of Ge, permits the attainment of an implanted Sn concentration in Ge of ˜15 at.% , which is about 2.5 times the maximum value previously attained. The crystallinity of the Ge-Sn layer following pulsed-laser-melting induced solidification is also greatly improved compared with that of uncapped material, thus opening up potential applications of the Ge-Sn alloy as a direct bandgap material fabricated by an ion beam synthesis technique.

  6. Ion implantation in ices and its relevance to the icy moons of the external planets

    NASA Astrophysics Data System (ADS)

    Strazzulla, G.; Baratta, G. A.; Fulvio, D.; Garozzo, M.; Leto, G.; Palumbo, M. E.; Spinella, F.

    2007-08-01

    Solid, atmosphere-less objects in the Solar System are continuously irradiated by energetic ions mostly in the keV-MeV energy range. Being the penetration depth of the incoming ions usually much lower than the thickness of the target, they are stopped into the ice. They deposit energy in the target induce the breaking of molecular bonds. The recombination of fragments produce different molecules. Reactive ions (e.g., H, C, N, O, S) induce all of the effects of any other ion, but in addition have a chance, by implantation in the target, to form new species containing the projectile. An ongoing research program performed at our laboratory has the aim to investigate ion implantation of reactive ions in many relevant ice mixtures. The results obtained so far indicate that some molecular species observed on icy planetary surfaces could not be native of that object but formed by implantation of reactive ions. In particular we present data obtained after: • C, N and S implantation in water ice • H implantation in carbon and sulfur dioxide

  7. 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)

  8. Modification of the passivity of iron based alloys through ion implantation

    SciTech Connect

    Wang, Y.F.

    1988-01-01

    As an unconventional surface alloying process, ion implantation has been utilized to improve the active-passive behavior and the pitting resistance of martensitic M50 engineering alloy. In a field simulation study, Cr-implantation only at 150 kev to a fluence of 2 {times} 10{sup 17} ions/cm{sup 2} prevented pitting. The best pitting resistance of the steel was obtained with multiple implantations of Cr and Mo. The intermixing effect of high fluence P-implantation into 304 stainless produced an amorphous surface alloy. The removal of the grain boundaries and the uniformity of the resulting structure had a great influence on corrosion properties. REED analysis indicated that the anodic passive films formed on P-implanted 304 stainless steel at 250 mV (SCE) in 0.5M H{sub 2}SO{sub 4} was amorphous. Phosphorus and boron were implanted into 316 stainless steel to study the passivity of 316 stainless. Electrochemical experiments were carried out to evaluate the effects of phosphorus and boron on general and localized corrosion resistance. XPS and auger analyses of the passive films formed on these implanted and unimplanted stainless steels were carried out to study the structure and chemical properties of the passive films. From these investigations, it seems likely that the bipolar mechanism of passivity may explain why the absence of the interfacial barrier oxide layer was responsible for the lack of pitting resistance of the P-implanted 316 stainless. The result of XPS spectra curve fitting carried out for films formed on a P-implanted 316 stainless steel steel indicated that a film rich in bound water only without a proper level of Cr in the film, did not resist Cl{sup {minus}} ion attack. The use of ion implantation as a tool to introduce desirable properties to the alloy was successful for studying the mechanism of passivity.

  9. 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.

  10. Assessment of CpTi Surface Properties after Nitrogen Ion Implantation with Various Doses and Energies

    NASA Astrophysics Data System (ADS)

    Fulazzaky, Mohamad Ali; Ali, Nurdin; Samekto, Haryanti; Ghazali, Mohd Imran

    2012-11-01

    Nitrogen ion implantation is one of the surface modification techniques used for increasing corrosion resistance of commercially pure titanium (CpTi). The nitrogen ion implanted CpTi in various doses markedly changes the corrosion resistance. Still the effect of nitrogen ion implantation on the CpTi at different energies needs to be verified. This study uses different methods to assess the CpTi surface properties after nitrogen ion implantation in various doses and energy. Surface hardness of the CpTi increases with an increase of the dose and decreases with an increase of the energy. The precipitation of the TiN increases with an increase of the nitrogen dose, and no formation of the Ti2N phase clearly appears. Corrosion resistance of the CpTi specimens can be upgraded to some extent after their surfaces are modified, implanting nitrogen ions at 100 keV by increasing dose. The optimum surface properties of the implanted CpTi are analyzed to contribute to materials science technology.

  11. Selective nucleation induced by defect nanostructures: A way to control cobalt disilicide precipitation during ion implantation

    SciTech Connect

    Fortuna, F.; Nguyen, M.-A.; Ruault, M.-O.; Kirk, M. A.; Borodin, V. A.; Ganchenkova, M. G.

    2012-12-15

    In this paper, we show a way to control cobalt disilicide precipitation during Co ion implantation at high temperatures (650 Degree-Sign C) by affecting radiation defects involved in precipitate nucleation and growth. We demonstrate that the relative shares of different precipitate types nucleated by implantation are strongly affected by defect microstructures deliberately created in investigated samples prior to cobalt implantation. Especially interesting is the effect of a dense ensemble of extremely small (1-3 nm) cavities, which promotes the formation of a relatively uniform layer of coherent cobalt disilicide precipitates with a narrow size distribution. In order to better understand the mechanism of the microstructural influence on the precipitate nucleation modes during Co implantation, we investigate the disilicide precipitation using different implantation setups and compare the results with those for cavity-free Si specimens implanted in similar conditions.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. Radiation Hardening of Ni-Ti Alloy Under Implantation of Inert Gases Heavy Ions

    NASA Astrophysics Data System (ADS)

    Poltavtseva, V.; Larionov, A.; Satpaev, D.; Gyngazova, M.

    2016-02-01

    The consistent patterns of changes in nano- and micro-hardness of Ni-Ti alloy with the shape memory effect after implantation of 40Ar8+ and 84Kr15+ ions depending on phase composition and implantation parameters have been experimentally studied. It has been shown that softening by 4 and 14% near the surface of the two-phase Ni-Ti alloy after implantation of 40Ar8+ and 84Kr15+ ions is connected with the differences in the nanostructure. Hardening of the near-surface layer of this alloy maximum by 118% at h = ∼3 pm and single-phase alloy in the entire region of the 40Ar8+ and 84Kr15+ ions range and in the out-range (h > Rp) area have been detected. The role of the current intensity of the ions beam in the change of nanohardness for the two-phase Ni-Ti alloy has been established.

  2. Influence of Si ion implantation on structure and morphology of g-C3N4

    NASA Astrophysics Data System (ADS)

    Varalakshmi, B.; Sreenivasulu, K. V.; Asokan, K.; Srikanth, V. V. S. S.

    2016-07-01

    Effect of Si ion implantation on structural and morphological features of graphite-like carbon nitride (g-C3N4) was investigated. g-C3N4 was prepared by using a simple atmospheric thermal decomposition process. The g-C3N4 pellets were irradiated with a Si ion beam of energy 200 keV with different fluencies. Structural, morphological and elemental, and phase analysis of the implanted samples in comparison with the pristine samples was carried out by using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) with energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) techniques, respectively. The observations revealed that Si ion implantation results in a negligible change in the crystallite size and alteration of the network-like to the sheet-like morphology of g-C3N4 and Si ions in the g-C3N4 network.

  3. Impact of Ion Implantation on Licorice (Glycyrrhiza uralensis Fisch) Growth and Antioxidant Activity Under Drought Stress

    NASA Astrophysics Data System (ADS)

    Liu, Jingnan; Tong, Liping; Shen, Tongwei; Li, Jie; Wu, Lijun; Yu, Zengliang

    2007-06-01

    Low energy ion beams are known to have stimulation effects on plant generation and to improve plants' intrinsic quality. In the present study, the growth and physiological index of licorice implanted with 0, 8, 10, 12 and 14× (2.6×1015) ions/cm2 were investigated under well-watered and drought-stress conditions. The results showed that a proper dose of ion implantation was particularly efficient in stimulating the licorice growth and improving the plant biomass significantly in both the well-watered and drought-stress conditions. The physiological results of licorice measured by leaf water potential, lipid oxidation, soluble protein and antioxidant system showed a significant correlation between ion implantation and water regime except for leaf water potential. Therefore, the study indicated that ion implantation can enhance licorice's drought tolerance by increasing the activity of superoxide dismutase (SOD), catalase (CAT) and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging ability to lower oxidative damage to lipids in plants. Ion beam implantation, therefore, provides an alternative method to enhance licorice drought tolerance.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Critical issues in the formation of quantum computer test structures by ion implantation

    SciTech Connect

    Schenkel, T.; Lo, C. C.; Weis, C. D.; Schuh, A.; Persaud, A.; Bokor, J.

    2009-04-06

    The formation of quantum computer test structures in silicon by ion implantation enables the characterization of spin readout mechanisms with ensembles of dopant atoms and the development of single atom devices. We briefly review recent results in the characterization of spin dependent transport and single ion doping and then discuss the diffusion and segregation behaviour of phosphorus, antimony and bismuth ions from low fluence, low energy implantations as characterized through depth profiling by secondary ion mass spectrometry (SIMS). Both phosphorus and bismuth are found to segregate to the SiO2/Si interface during activation anneals, while antimony diffusion is found to be minimal. An effect of the ion charge state on the range of antimony ions, 121Sb25+, in SiO2/Si is also discussed.

  9. 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

  10. 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.

  11. Silicon defects characterization for low temperature ion implantation and RTA process

    NASA Astrophysics Data System (ADS)

    Martirani Paolillo, Diego; Margutti, Giovanni; De Biase, Marco; Barozzi, Mario; Giubertoni, Damiano; Spaggiari, Claudio

    2015-12-01

    In the last years a lot of effort has been directed in order to reduce silicon defects eventually formed during the ion implantation/anneal sequence used in the fabrication of CMOS devices. In this work we explored the effect of ion implant dose rate and temperature on the formation of silicon defects for high fluence 49BF2 implantations. The considered processes (implantation and annealing) conditions are those typically used to form the source/drain regions of p-channel transistors in the submicron technology node and will be detailed in the document. Characterization of implant damage and extended silicon defects left after anneal has been performed by TEM. Dopant distribution and dopant activation has been investigated by SIMS and SRP analysis. We have verified that implant dose rate and temperature modulate the thickness of the amorphous silicon observed after implant, as well as the concentrations of silicon defects left after anneal. Effect of high dose rate low temperature implantation on product device was also evaluated, showing a reduction of leakage current on p-channel transistors. Experimental set up, results and possible explanation will be reported and discussed in the paper.

  12. Neuron cell positioning on polystyrene in culture by silver-negative ion implantation and region control of neural outgrowth

    NASA Astrophysics Data System (ADS)

    Tsuji, Hiroshi; Sato, Hiroko; Baba, Takahiro; Ikemura, Shin'ichi; Gotoh, Yasuhito; Ishikawa, Junzo

    2000-05-01

    A new method to control the position of neuron cell attachment and extension region of neural outgrowth has been developed by using a pattering ion implantation with silver-negative ions into polystyrene dishes. This technique offers a promising method to form an artificially designed neural network in cell culture in vitro. Silver-negative ions were implanted into non-treated polystyrene dishes (NTPS) at conditions of 20 keV and 3×1015 ions/cm2 through a pattering mask, which had as many as 67 slits of 60 μm in width and 4 mm in length with a spacing of 60 μm. For cell culture in vitro, nerve cells of PC-12h (rat adrenal phechromocytoma) were used because they respond to a nerve growth factor (NGF). In the first 2 days in culture without NGF, we observed a selective cell attachment only to the ion-implanted region in patterning Ag- implanted polystyrene sample (p-Ag/NTPS). In another 2 days in culture with NGF, the nerve cells expanded neurites only over the ion-implanted region. For collagen-coated p-Ag/NTPS sample of which collagen was coated after the ion implantation (Collagen/p-Ag/NTPS), most nerve cells were also attached on the ion-implanted region. However, neurites expanded in both ion-implanted and unimplanted regions. The contact angle of NTPS decreased after the ion implantation from 86° to 74°. The region selectivity of neuron attachment and neurite extension is considered to be due to contact angle lowering by the ion implantation as radiation effect on the surface.

  13. 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.

  14. 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.

  15. A Self-Aligned Gate AlGaAs/GaAs Heterostructure Field-Effect Transistor with an Ion-Implanted Buried-Channel for use in High Efficiency Power Amplifiers

    NASA Astrophysics Data System (ADS)

    Nishihori, Kazuya; Kitaura, Yoshiaki; Tanabe, Yoshikazu; Mihara, Masakatsu; Yoshimura, Misao; Nitta, Tomohiro; Kakiuchi, Yorito; Uchitomi, Naotaka

    1998-06-01

    In this paper we report on a self-aligned gate buried-channel Al0.22Ga0.78As/GaAs heterostructure field-effect transistor (BC-HFET). The BC-HFET comprises a selectively ion-implanted channel and an undoped i-AlGaAs surface layer. In order to realize the buried channel heterostructure, a combined process of ion-implantation and epitaxial growth is developed. The post-implantation annealing before the epitaxial growth successfully reduces the interdiffusion at the heterointerface between the ion-implanted GaAs channel and the AlGaAs surface layer. The BC-HFET overcomes the disadvantages of a low breakdown voltage which exists in conventional self-aligned gate MESFETs. The BC-HFET exhibits a high breakdown voltage of 8 V and a high Schottky barrier height of 0.75 eV. The 1-mm-wide power BC-HFET demonstrates an output power of 18.2 dBm and a drain efficiency of 50% at a low adjacent channel leakage power of -59 dBc for a 1.9-GHz π/4-shifted quadrature phase shift keying (QPSK) modulated input, for use as Personal Handy-phone System handsets.

  16. Metal Ion-Loaded Nanofibre Matrices for Calcification Inhibition in Polyurethane Implants

    PubMed Central

    Singh, Charanpreet; Wang, Xungai

    2017-01-01

    Pathologic calcification leads to structural deterioration of implant materials via stiffening, stress cracking, and other structural disintegration mechanisms, and the effect can be critical for implants intended for long-term or permanent implantation. This study demonstrates the potential of using specific metal ions (MI)s for inhibiting pathological calcification in polyurethane (PU) implants. The hypothesis of using MIs as anti-calcification agents was based on the natural calcium-antagonist role of Mg2+ ions in human body, and the anti-calcification effect of Fe3+ ions in bio-prosthetic heart valves has previously been confirmed. In vitro calcification results indicated that a protective covering mesh of MI-doped PU can prevent calcification by preventing hydroxyapatite crystal growth. However, microstructure and mechanical characterisation revealed oxidative degradation effects from Fe3+ ions on the mechanical properties of the PU matrix. Therefore, from both a mechanical and anti-calcification effects point of view, Mg2+ ions are more promising candidates than Fe3+ ions. The in vitro MI release experiments demonstrated that PU microphase separation and the structural design of PU-MI matrices were important determinants of release kinetics. Increased phase separation in doped PU assisted in consistent long-term release of dissolved MIs from both hard and soft segments of the PU. The use of a composite-sandwich mesh design prevented an initial burst release which improved the late (>20 days) release rate of MIs from the matrix. PMID:28644382

  17. 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.

  18. Intravascular brachytherapy with radioactive stents produced by ion implantation

    NASA Astrophysics Data System (ADS)

    Golombeck, M.-A.; Heise, S.; Schloesser, K.; Schuessler, B.; Schweickert, H.

    2003-05-01

    About 1 million patients are treated for stenosis of coronary arteries by percutaneous balloon angioplasty annually worldwide. In many cases a so called stent is inserted into the vessel to keep it mechanically open. Restenosis is observed in about 20-30% of these cases, which can be treated by irradiating the stented vessel segment. In our approach, we utilized the stent itself as radiation source by ion implanting 32P. Investigations of the surface properties were performed with special emphasis on activity retention. Clinical data of about 400 patients showed radioactive stents can suppress instent restenosis, but a so called edge effect appeared, which can be avoided by the new "drug eluting stents".

  19. Rutherford Backscattering Spectrometry studies of 100 keV nitrogen ion implanted polypropylene polymer

    NASA Astrophysics Data System (ADS)

    Chawla, Mahak; Aggarwal, Sanjeev; Sharma, Annu

    2017-09-01

    The effect of nitrogen ion implantation on the structure and composition in polypropylene (PP) polymer has been studied. Implantation was carried out using 100 keV N+ ions at different fluences of 1 × 1015, 1 × 1016 and 1 × 1017 ions cm-2 with beam current density of ∼0.65 μA cm-2. Surface morphological changes in the pre- and post-implanted PP specimens have been studied using Rutherford Backscattering Spectrometry (RBS) and UV-Visible Spectroscopy. The spatial distribution of implantation induced modification in the form of carbonization and dehydrogenation in the near surface region of PP matrix, the projected range, retained dose of implanted nitrogen, the various elements present in the implanted layers and their differential cross-sections have been analyzed using RBS spectra. RUMP simulation yielded an increase in the concentration of carbon near the surface from 33 at.% (virgin) to 42 at.% at fluence of 1 × 1017 N+ cm-2. Further, optical absorption has been found to increase with a shift in the absorption edge from UV towards visible region with increasing fluence. UV-Vis absorption spectra also indicate a drastic decrease in optical energy gap from 4.12 eV (virgin) to 0.25 eV (1 × 1017 N+ cm-2) indicating towards the formation of carbonaceous network in the implanted region. All these changes observed using UV-Visible have been further correlated with the outcomes of the RBS characterization.

  20. RTV silicone rubber surface modification for cell biocompatibility by negative-ion implantation

    NASA Astrophysics Data System (ADS)

    Zheng, Chenlong; Wang, Guangfu; Chu, Yingjie; Xu, Ya; Qiu, Menglin; Xu, Mi

    2016-03-01

    A negative cluster ion implantation system was built on the injector of a GIC4117 tandem accelerator. Next, the system was used to study the surface modification of room temperature vulcanization silicone rubber (RTV SR) for cell biocompatibility. The water contact angle was observed to decrease from 117.6° to 99.3° as the C1- implantation dose was increased to 1 × 1016 ions/cm2, and the effects of C1-, C2- and O1- implantation result in only small differences in the water contact angle at 3 × 1015 ions/cm2. These findings indicate that the hydrophilicity of RTV SR improves as the dose is increased and that the radiation effect has a greater influence than the doping effect on the hydrophilicity. There are two factors influence hydrophilicity of RTV: (1) based on the XPS and ATR-FTIR results, it can be inferred that ion implantation breaks the hydrophobic functional groups (Sisbnd CH3, Sisbnd Osbnd Si, Csbnd H) of RTV SR and generates hydrophilic functional groups (sbnd COOH, sbnd OH, Sisbnd (O)x (x = 3,4)). (2) SEM reveals that the implanted surface of RTV SR appears the micro roughness such as cracks and wrinkles. The hydrophilicity should be reduced due to the lotus effect (Zhou Rui et al., 2009). These two factors cancel each other out and make the C-implantation sample becomes more hydrophilic in general terms. Finally, cell culture demonstrates that negative ion-implantation is an effective method to improve the cell biocompatibility of RTV SR.

  1. A study of the behaviour of copper in different types of silicate glasses implanted with Cu+ and O+ ions

    NASA Astrophysics Data System (ADS)

    Švecová, B.; Vařák, P.; Vytykáčová, S.; Nekvindová, P.; Macková, A.; Malinský, P.; Böttger, R.

    2017-09-01

    Glasses containing copper are promising photonic materials for lasing devices and all-optical components. It has already been shown that the oxidation state of the implants depends on many factors. This paper is going to report on one of them, i.e. the influence of the composition of a silicate glass matrix on the behaviour of the implanted Cu ions before and after a subsequent implantation of oxygen ions. Three types of silicate glasses having a different extent of cross-linking were implanted with copper ions with an energy of 330 keV and a fluence 1 × 1016 ions cm-2. Then the glasses were implanted with oxygen ions with an energy of 110 keV into the same depth as the already implanted Cu ions. The concentration depth profiles of Cu in the glasses were studied by Rutherford Backscattering Spectrometry. After the implantation, the samples were characterised by optical absorption and photoluminescence spectroscopy. The samples were annealed in ambient atmosphere for 1 h at 600 °C, which is near the transformation temperature of those glasses. The effect of annealing on the distribution of the implants and on the absorption and emission spectra of the as-implanted glasses will be discussed as well.

  2. First order Raman scattering analysis of transition metal ions implanted GaN

    NASA Astrophysics Data System (ADS)

    Majid, Abdul; Rana, Usman Ali; Shakoor, Abdul; Ahmad, Naeem; Hassan, Najam al; Khan, Salah Ud-Din

    2016-03-01

    Transition Metal (TM) ions V, Cr, Mn and Co were implanted into GaN/sapphire films at fluences 5×1014, 5×1015 and 5×1016 cm-2. First order Raman Scattering (RS) measurements were carried out to study the effects of ion implantation on the microstructure of the materials, which revealed the appearance of disorder and new phonon modes in the lattice. The variations in characteristic modes 1GaN i.e. E2(high) and A1(LO), observed for different implanted samples is discussed in detail. The intensity of nitrogen vacancy related vibrational modes appearing at 363 and 665 cm-1 was observed for samples having different fluences. A gallium vacancy related mode observed at 277/281 cm-1 for TM ions implanted at 5×1014 cm-2 disappeared for all samples implanted with rest of fluences. The fluence dependent production of implantation induced disorder and substitution of TM ions on cationic sites is discussed, which is expected to provide necessary information for the potential use of these materials as diluted magnetic semiconductors in future spintronic devices.

  3. Investigation of Donor and Acceptor Ion Implantation in AlN

    SciTech Connect

    Osinsky, Andrei

    2015-09-16

    AlGaN alloys with high Al composition and AlN based electronic devices are attractive for high voltage, high temperature applications, including microwave power sources, power switches and communication systems. AlN is of particular interest because of its wide bandgap of ~6.1eV which is ideal for power electronic device applications in extreme environments which requires high dose ion implantation. One of the major challenges that need to be addressed to achieve full utilization of AlN for opto and microelectronic applications is the development of a doping strategy for both donors and acceptors. Ion implantation is a particularly attractive approach since it allows for selected-area doping of semiconductors due to its high spatial and dose control and its high throughput capability. Active layers in the semiconductor are created by implanting a dopant species followed by very high temperature annealing to reduce defects and thereby activate the dopants. Recovery of implant damage in AlN requires excessively high temperature. In this SBIR program we began the investigation by simulation of ion beam implantation profiles for Mg, Ge and Si in AlN over wide dose and energy ranges. Si and Ge are implanted to achieve the n-type doping, Mg is investigated as a p-type doping. The simulation of implantation profiles were performed in collaboration between NRL and Agnitron using a commercial software known as Stopping and Range of Ions in Matter (SRIM). The simulation results were then used as the basis for ion implantation of AlN samples. The implanted samples were annealed by an innovative technique under different conditions and evaluated along the way. Raman spectroscopy and XRD were used to determine the crystal quality of the implanted samples, demonstrating the effectiveness of annealing in removing implant induced damage. Additionally, SIMS was used to verify that a nearly uniform doping profile was achieved near the sample surface. The electrical characteristics

  4. Ion implantation and dynamic recovery of tin-doped indium oxide films

    SciTech Connect

    Shigesato, Yuzo; Paine, D.C.; Haynes, T.E.

    1993-09-01

    The effect of O{sup +} on implantation on the electronic (carrier density, mobility), resistivity and microstructural properties of thin film Sn-doped In{sub 2}O{sub 3} (ITO) was studied. Both polycrystalline (c-) and amorphous (a-) ITO thin films, 200 nm thick, were implanted at substrate temperatures ranging from {minus}196 to 300{degrees} C with 80 keV O{sup +} at doses ranging from 0 to 4.0{times}10{sup 15} cm{sup {minus}2}. X-ray diffraction studies show that polycrystalline ITO remains crystalline even after implantation with 80 keV O{sup +} at {minus}196{degrees}C to a dose of 4.0{times}10{sup 15} cm{sup {minus}2} which suggests that dynamic recovery processes are active in ITO at this low temperature. Although the x-ray diffraction pattern of the polycrystalline ITO remains unchanged with implant dose, the electrical properties were seen to degrade when implanted to a dose of 1.0{times}10{sup 15}cm{sup {minus}2} below 200{degrees}C. In contrast, amorphous ITO films remains amorphous upon ion implantation and shows almost no degradation in resistivity when implanted below 16{degrees}C. The recrystallization temperature of amorphous ITO is about 150{degrees}C in the absence of ion implantation.

  5. 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.

  6. 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

  7. Use of low energy hydrogen ion implants in high efficiency crystalline silicon solar cells

    NASA Technical Reports Server (NTRS)

    Fonash, S. J.; Singh, R.

    1985-01-01

    This program is a study of the use of low energy hydrogen ion implantation for high efficiency crystalline silicon solar cells. The first quarterly report focuses on two tasks of this program: (1) an examination of the effects of low energy hydrogen implants on surface recombination speed; and (2) an examination of the effects of hydrogen on silicon regrowth and diffusion in silicon. The first part of the project focussed on the measurement of surface properties of hydrogen implanted silicon. Low energy hydrogen ions when bombarded on the silicon surface will create structural damage at the surface, deactivate dopants and introduce recombination centers. At the same time the electrically active centers such as dangling bonds will be passivated by these hydrogen ions. Thus hydrogen is expected to alter properties such as the surface recombination velocity, dopant profiles on the emitter, etc. In this report the surface recombination velocity of a hydrogen emplanted emitter was measured.

  8. 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.

  9. 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.

  10. 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

  11. Optical properties of multicomponent cadmium-silver nanocluster composites formed in silica by sequential ion implantation

    SciTech Connect

    Zuhr, R.A.; Magruder, R.H. III; Anderson, T.S.

    1996-11-01

    Formation and optical properties of nanometer dimension metal colloid composites formed by sequential implantation of Cd then Ag and by single element implantations of Cd and Ag in silica were characterized by TEM and optical spectroscopy. A nominal dose of 6x10{sup 16} ions/cm{sup 2} as determined by current integration was used for both ion species. Doses used for the sequential implantations were a 1 to 1 ratio of Cd to Ag. Sequential implantations of Cd and Ag led to formation of both multi-component metal nanoclusters and elemental nanoclusters. Electron diffraction indicated that the polycrystalline particles of Ag{sub 5}Cd{sub 8} and elemental Ag were formed. The optical response was consistent with results expected from effective medium theory.

  12. 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.

  13. 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.

  14. Effects of high-dose hydrogen implantation on defect formation and dopant diffusion in silver implanted ZnO crystals

    SciTech Connect

    Yaqoob, Faisal; Huang, Mengbing

    2016-07-28

    This work reports on the effects of a deep high-dose hydrogen ion implant on damage accumulation, defect retention, and silver diffusion in silver implanted ZnO crystals. Single-crystal ZnO samples were implanted with Ag ions in a region ∼150 nm within the surface, and some of these samples were additionally implanted with hydrogen ions to a dose of 2 × 10{sup 16 }cm{sup −2}, close to the depth ∼250 nm. Rutherford backscattering/ion channeling measurements show that crystal damage caused by Ag ion implantation and the amount of defects retained in the near surface region following post-implantation annealing were found to diminish in the case with the H implantation. On the other hand, the additional H ion implantation resulted in a reduction of substitutional Ag atoms upon post-implantation annealing. Furthermore, the presence of H also modified the diffusion properties of Ag atoms in ZnO. We discuss these findings in the context of the effects of nano-cavities on formation and annihilation of point defects as well as on impurity diffusion and trapping in ZnO crystals.

  15. Effects of high-dose hydrogen implantation on defect formation and dopant diffusion in silver implanted ZnO crystals

    NASA Astrophysics Data System (ADS)

    Yaqoob, Faisal; Huang, Mengbing

    2016-07-01

    This work reports on the effects of a deep high-dose hydrogen ion implant on damage accumulation, defect retention, and silver diffusion in silver implanted ZnO crystals. Single-crystal ZnO samples were implanted with Ag ions in a region ˜150 nm within the surface, and some of these samples were additionally implanted with hydrogen ions to a dose of 2 × 1016 cm-2, close to the depth ˜250 nm. Rutherford backscattering/ion channeling measurements show that crystal damage caused by Ag ion implantation and the amount of defects retained in the near surface region following post-implantation annealing were found to diminish in the case with the H implantation. On the other hand, the additional H ion implantation resulted in a reduction of substitutional Ag atoms upon post-implantation annealing. Furthermore, the presence of H also modified the diffusion properties of Ag atoms in ZnO. We discuss these findings in the context of the effects of nano-cavities on formation and annihilation of point defects as well as on impurity diffusion and trapping in ZnO crystals.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Charge transport and storage in ion implanted metal-oxide-semiconductor structures

    NASA Astrophysics Data System (ADS)

    Augulis, L.; Pranevičius, L.; Vosylius, J.

    A physical model that predicts charge accumulation in MOS structures with implanted SiO 2 is investigated theoretically and experimentally. It is shown that, to achieve memory effects, MOS structures have to include a SiO 2 layer with different conduction mechanism along its thickness. The sign of the flat-band voltage shift depends on the localization of traps in oxide created by ion implantation. The time characteristics of charge accumulation and discharging of implanted SiO 2 by the pulses of applied voltage are similar to those observed in MNOS structures.

  5. DLTS of low-energy hydrogen ion implanted n-Si

    NASA Astrophysics Data System (ADS)

    Deenapanray, Prakash N. K.

    2003-12-01

    We have used deep level transient spectroscopy and capacitance-voltage measurements to study the influence of low-energy hydrogen ion implantation on the creation of defects in n-Si. In particular, we have studied the ion fluence dependence of the free carrier compensation at room temperature, and we have measured the generation of VO-H complex and VP-pair in ion implanted samples. The 7.5 keV H ions created defects in the top 0.3 μm of samples, which resulted in carrier compensation to depths exceeding 1 μm. This effect is not due to defects created by ion channeling but is rather due to the migration of defects as demonstrated using binary collision code MARLOWE.

  6. Effective dopant activation by susceptor-assisted microwave annealing of low energy boron implanted and phosphorus implanted silicon

    SciTech Connect

    Zhao, Zhao; Vemuri, Rajitha N. P.; Alford, T. L.; David Theodore, N.; Lu, Wei; Lau, S. S.; Lanz, A.

    2013-12-28

    Rapid processing and reduced end-of-range diffusion result from susceptor-assisted microwave (MW) annealing, making this technique an efficient processing alternative for electrically activating dopants within ion-implanted semiconductors. Sheet resistance and Hall measurements provide evidence of electrical activation. Susceptor-assisted MW annealing, of ion-implanted Si, enables more effective dopant activation and at lower temperatures than required for rapid thermal annealing (RTA). Raman spectroscopy and ion channeling analyses are used to monitor the extent of ion implantation damage and recrystallization. The presence and behavior of extended defects are monitored by cross-section transmission electron microscopy. Phosphorus implanted Si samples experience effective electrical activation upon MW annealing. On the other hand, when boron implanted Si is MW annealed, the growth of extended defects results in reduced crystalline quality that hinders the electrical activation process. Further comparison of dopant diffusion resulting from MW annealing and rapid thermal annealing is performed using secondary ion mass spectroscopy. MW annealed ion implanted samples show less end-of-range diffusion when compared to RTA samples. In particular, MW annealed P{sup +} implanted samples achieve no visible diffusion and equivalent electrical activation at a lower temperature and with a shorter time-duration of annealing compared to RTA. In this study, the peak temperature attained during annealing does not depend on the dopant species or dose, for susceptor-assisted MW annealing of ion-implanted Si.

  7. 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

  8. Comparison Between Simulated And Experimental Au-ion Profiles Implanted in nanocrystalline ceria

    SciTech Connect

    Moll, Sandra J.; Zhang, Yanwen; Zhu, Zihua; Edmondson, Philip D.; Namavar, Fereydoon; Weber, William J.

    2013-07-15

    Radiation response of nanocrystalline ceria films deposited on a silicon substrate was investigated under a 3-MeV Au-ion irradiation at 300 K. A uniform grain growth cross the ceria films is observed and effective densification of the ceria thin films occurs during irradiation. The Au ion profiling was measured by secondary ion mass spectrometry (SIMS) and compared to the Au ion distribution predicted by the Stopping and Range of Ions in Solids (SRIM) code. It is observed that the Au-ion penetration depth is underestimated in comparison with the SIMS measurements. An overestimation of the electronic stopping power for heavy incident ions in the SRIM program may account for the discrepancies between the calculations and the SIMS experimental results. This work presents an approach to compensate the overestimation of the electronic stopping powers in the SRIM program by adjusting the nanocrystalline ceria target density to better predict the ion implantation profile.

  9. Comparison between simulated and experimental Au-ion profiles implanted in nanocrystalline ceria

    SciTech Connect

    Moll, Sandra; Zhang, Yanwen; Zhu, Zihua; Edmondson, Dr. Philip; Namavar, Fereydoon; Weber, William J

    2013-01-01

    Radiation response of nanocrystalline ceria films deposited on a silicon substrate was investigated under a 3-MeV Au-ion irradiation at 300 K. A uniform grain growth cross the ceria films is observed and effective densification of the ceria thin films occurs during irradiation. The Au ion profiling was measured by secondary ion mass spectrometry (SIMS) and compared to the Au ion distribution predicted by the Stopping and Range of Ions in Solids (SRIM) code. It is observed that the Au-ion penetration depth is underestimated in comparison with the SIMS measurements. An overestimation of the electronic stopping power for heavy incident ions in the SRIM program may account for the discrepancies between the calculations and the SIMS experimental results. This work presents an approach to compensate the overestimation of the electronic stopping powers in the SRIM program by adjusting the nanocrystalline ceria target density to better predict the ion implantation profile.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Optical planar waveguide in magnesium aluminate spinel crystal using oxygen ion implantation

    NASA Astrophysics Data System (ADS)

    Song, Hong-Lian; Yu, Xiao-Fei; Zhang, Lian; Wang, Tie-Jun; Qiao, Mei; Liu, Peng; Zhao, Jin-Hua; Wang, Xue-Lin

    2015-07-01

    A planar optical waveguide in MgAl2O4 crystal sample was fabricated using 6.0 MeV oxygen ion implantation at a fluence of 1.5 × 1015 ions/cm2 at room temperature. The optical modes were measured at a wavelength of 633 nm using a model 2010 prism coupler. The near-field intensity files in the visible band were measured and simulated with end-face coupling and FD-BPM methods, respectively. The absorption spectra show that the implantation process has almost no effect on the visible and near-infrared band absorption.

  16. Study of Nickel Ion Release in Simulated Body Fluid from C+-IMPLANTED Nickel Titanium Alloy

    NASA Astrophysics Data System (ADS)

    Shafique, Muhammad Ahsan; Murtaza, G.; Saadat, Shahzad; Zaheer, Zeeshan; Shahnawaz, Muhammad; Uddin, Muhammad K. H.; Ahmad, Riaz

    2016-05-01

    Nickel ion release from NiTi shape memory alloy is an issue for biomedical applications. This study was planned to study the effect of C+ implantation on nickel ion release and affinity of calcium phosphate precipitation on NiTi alloy. Four annealed samples are chosen for the present study; three samples with oxidation layer and the fourth without oxidation layer. X-ray diffraction (XRD) spectra reveal amorphization with ion implantation. Proton-induced X-ray emission (PIXE) result shows insignificant increase in Ni release in simulated body fluid (SBF) and calcium phosphate precipitation up to 8×1013ions/cm2. Then Nickel contents show a sharp increase for greater ion doses. Corrosion potential decreases by increasing the dose but all the samples passivate after the same interval of time and at the same level of VSCE in ringer lactate solution. Hardness of samples initially increases at greater rate (up to 8×1013ions/cm2) and then increases with lesser rate. It is found that 8×1013ions/cm2 (≈1014) is a safer limit of implantation on NiTi alloy, this limit gives us lesser ion release, better hardness and reasonable hydroxyapatite incubation affinity.

  17. Hybrid gas-metal co-implantation with a modified vacuum arc ion source

    SciTech Connect

    Oks, E.M.; Yushkov, G.Y.; Evans, P.J.; Oztarhan, A.; Brown, I.G.; Dickinson, M.R.; Liu, F.; MacGill, R.A.; Monteiro, O.R.; Wang, Z.

    1996-08-01

    Energetic beams of mixed metal and gaseous ion species can be generated with a vacuum arc ion source by adding gas to the arc discharge region. This could be an important tool for ion implantation research by providing a method for forming buried layers of mixed composition such as e.g. metal oxides and nitrides. In work to date, we have formed a number of mixed metal-gas ion beams including Ti+N, Pt+N, Al+O, and Zr+O. The particle current fractions of the metal-gas ion components in the beam ranged from 100% metallic to about 80% gaseous, depending on operational parameters. We have used this new variant of the vacuum arc ion source to carry out some exploratory studies of the effect of Al+O and Zr+O co-implantation on tribology of stainless steel. Here we describe the ion source modifications, species and charge state of the hybrid beams produced, and results of preliminary studies of surface modification of stainless steel by co-implantation of mixed Al/O or Zr/O ion beams. 5 figs, 21 refs.

  18. 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.

  19. 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.

  20. Effect of implant design on initial stability of tapered implants.

    PubMed

    Chong, Linus; Khocht, Ahmed; Suzuki, Jon B; Gaughan, John

    2009-01-01

    Implant design is one of the parameters for achieving successful primary stability. This study aims to examine the effect of a self-tapping blades implant design on initial stability in tapered implants. Polyurethane blocks of different densities were used to simulate different bone densities. The two different implant designs included one with self-tapping blades and one without self-tapping blades. Implants were placed at 3 different depths: apical third, middle third, and fully inserted at 3 different densities of polyurethane blocks. A resonance frequency (RF) analyzer was then used to measure stability of the implants. Repeated-measures analysis of variance was used to examine the effect of implant design, insertion depth, and block density on RF. Analysis of covariance was used to examine the strength of association between RF and the aforementioned factors. In both medium-density (P = .017) and high-density (P = .002) blocks, fully inserted non-self-tapping implants showed higher initial stability than self-tapping implants. No differences were noted between the 2 implant designs that were not fully inserted. The highest strength of association was with insertion depth (standardized beta [std beta] = -0.60, P = .0001), followed by block density (std beta = -0.15, P = .0002). Implant design showed a weak association (std beta = -0.07, P = .09). In conclusion, fully inserted implants without self-tapping blades have higher initial stability than implants with self-tapping blades. However, the association strength between implant design and initial stability is less relevant than other factors, such as insertion depth and block density. Thus, if bone quality and quantity are optimal, they may compensate for design inadequacy.

  1. 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.

  2. Copper ion implanted aluminum nitride dilute magnetic semiconductors (DMS) prepared by molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Shah, A.; Ahmad, Jamil; Ahmad, Ishaq; Mehmood, Mazhar; Mahmood, Arshad; Rasheed, Muhammad Asim

    2014-10-01

    Diluted magnetic semiconductor (DMS) AlN:Cu films were fabricated by implanting Cu+ ions into AlN thin films at various ion fluxes. AlN films were deposited on c-plane sapphire by molecular beam epitaxy followed by Cu+ ion implantation. The structural and magnetic characterization of the samples was performed through Rutherford backscattering and channeling spectrometry (RBS/C), X-ray diffraction (XRD), Raman spectroscopy, vibrating sample magnetometer (VSM) and SQUID. Incorporation of copper into the AlN lattice was confirmed by RBS, while XRD revealed that no new phase was formed as a result of ion implantation. RBS also indicated formation of defects as a result of implantation process and the depth and degree of damage increased with an increase in ion fluence. Raman spectra showed only E2 (high) and A1 (LO) modes of wurtzite AlN crystal structure and confirmed that no secondary phases were formed. It was found that both Raman modes shift with Cu+ fluences, indicating that Cu ion may go to interstitial or substitutional sites resulting in distortion or damage of lattice. Although as implanted samples showed no magnetization, annealing of the samples resulted in appearance of room temperature ferromagnetism. The saturation magnetization increased with both the annealing temperature as well as with ion fluence. FC/ZFC measurements indicated that the ferromagnetic effect was not related with superparamagnetic phase formation. In spite, it was due to the formation of AlN based DMS material. The Curie temperature (TC) of the sample prepared at an ion fluence of 5 × 1015 cm-2 and an annealing temperature of 950 °C was found to lie above 340 K.

  3. 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.

  4. 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.

  5. 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)

  6. Fe ion-implanted TiO2 thin film for efficient visible-light photocatalysis

    NASA Astrophysics Data System (ADS)

    Impellizzeri, G.; Scuderi, V.; Romano, L.; Sberna, P. M.; Arcadipane, E.; Sanz, R.; Scuderi, M.; Nicotra, G.; Bayle, M.; Carles, R.; Simone, F.; Privitera, V.

    2014-11-01

    This work shows the application of metal ion-implantation to realize an efficient second-generation TiO2 photocatalyst. High fluence Fe+ ions were implanted into thin TiO2 films and subsequently annealed up to 550 °C. The ion-implantation process modified the TiO2 pure film, locally lowering its band-gap energy from 3.2 eV to 1.6-1.9 eV, making the material sensitive to visible light. The measured optical band-gap of 1.6-1.9 eV was associated with the presence of effective energy levels in the energy band structure of the titanium dioxide, due to implantation-induced defects. An accurate structural characterization was performed by Rutherford backscattering spectrometry, transmission electron microscopy, Raman spectroscopy, X-ray diffraction, and UV/VIS spectroscopy. The synthesized materials revealed a remarkable photocatalytic efficiency in the degradation of organic compounds in water under visible light irradiation, without the help of any thermal treatments. The photocatalytic activity has been correlated with the amount of defects induced by the ion-implantation process, clarifying the operative physical mechanism. These results can be fruitfully applied for environmental applications of TiO2.

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. Performance improvement of silicon nitride ball bearings by ion implantation. CRADA final report

    SciTech Connect

    Williams, J.M.; Miner, J.

    1998-03-01

    The present report summarizes technical results of CRADA No. ORNL 92-128 with the Pratt and Whitney Division of United Technologies Corporation. The stated purpose of the program was to assess the 3effect of ion implantation on the rolling contact performance of engineering silicon nitride bearings, to determine by post-test analyses of the bearings the reasons for improved or reduced performance and the mechanisms of failure, if applicable, and to relate the overall results to basic property changes including but not limited to swelling, hardness, modulus, micromechanical properties, and surface morphology. Forty-two control samples were tested to an intended runout period of 60 h. It was possible to supply only six balls for ion implantation, but an extended test period goal of 150 h was used. The balls were implanted with C-ions at 150 keV to a fluence of 1.1 {times} 10{sup 17}/cm{sup 2}. The collection of samples had pre-existing defects called C-cracks in the surfaces. As a result, seven of the control samples had severe spalls before reaching the goal of 60 h for an unacceptable failure rate of 0.003/sample-h. None of the ion-implanted samples experienced engineering failure in 150 h of testing. Analytical techniques have been used to characterize ion implantation results, to characterize wear tracks, and to characterize microstructure and impurity content. In possible relation to C-cracks. It is encouraging that ion implantation can mitigate the C-crack failure mode. However, the practical implications are compromised by the fact that bearings with C-cracks would, in no case, be acceptable in engineering practice, as this type of defect was not anticipated when the program was designed. The most important reason for the use of ceramic bearings is energy efficiency.

  14. 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.

  15. 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

  16. Magnetization control for bit pattern formation of spinel ferromagnetic oxides by Kr ion implantation

    SciTech Connect

    Kita, Eiji Suzuki, Kazuya Z.; Liu, Yang; Utsumi, Yuji; Morishita, Jumpei; Niizeki, Tomohiko; Yanagihara, Hideto; Oshima, Daiki; Kato, Takeshi; Mibu, Ko

    2014-05-07

    As a first step toward the development of bit-patterned magnetic media made of oxides, we investigated the effectiveness of magnetism control by Kr implantation in a typical spinel ferromagnetic oxide, Fe{sub 3}O{sub 4}. We implanted Kr ions accelerated at 30 kV on 13-nm-thick Fe{sub 3}O{sub 4} thin films at dosages of (1–40) × 10{sup 14} ions/cm{sup 2}. Magnetization decreased with increase in ion dosages and disappeared when irradiation was greater than 2 × 10{sup 15} ions/cm{sup 2} of Kr ions. These dosages are more than ten times smaller than that used in the N{sub 2} implantation for metallic and oxide ferromagnets. Both the temperature dependence of magnetization and the Mössbauer study suggest that the transition of Fe{sub 3}O{sub 4} from ferromagnetic to paramagnetic took place sharply due to Kr ion irradiation, which produces two-phase separation—ferromagnetic and nonmagnetic with insufficient dosage of Kr ions.

  17. 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

  18. 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.

  19. Influence of irradiation spectrum and implanted ions on the amorphization of ceramics

    SciTech Connect

    Zinkle, S.J.; Snead, L.L.

    1995-12-31

    Polycrystalline Al2O3, magnesium aluminate spinel (MgAl2O4), MgO, Si3N4, and SiC were irradiated with various ions at 200-450 K, and microstructures were examined following irradiation using cross-section TEM. Amorphization was not observed in any of the irradiated oxide ceramics, despsite damage energy densities up to {similar_to}7 keV/atom (70 displacements per atom). On the other hand, SiC readily amorphized after damage levels of {similar_to}0.4 dpa at room temperature (RT). Si3N4 exhibited intermediate behavior; irradiation with Fe{sup 2+} ions at RT produced amorphization in the implanted ion region after damage levels of {similar_to}1 dpa. However, irradiated regions outside the implanted ion region did not amorphize even after damage levels > 5 dpa. The amorphous layer in the Fe-implanted region of Si3N4 did not appear if the specimen was simultaneoulsy irradiated with 1-MeV He{sup +} ions at RT. By comparison with published results, it is concluded that the implantation of certain chemical species has a pronounced effect on the amorphization threshold dose of all five materials. Intense ionizing radiation inhibits amorphization in Si3N4, but does not appear to significantly influence the amorphization of SiC.

  20. 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.

  1. 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.

  2. 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

  3. Gettering of transition metals by cavities in silicon formed by helium ion implantation

    SciTech Connect

    Petersen, G.A.; Myers, S.M.; Follstaedt, D.M.

    1996-09-01

    We have recently completed studies which quantitatively characterize the ability of nanometer-size cavities formed by He ion implantation to getter detrimental metal impurities in Si. Cavity microstructures formed in Si by ion implantation of He and subsequent annealing have been found to capture metal impurities by two mechanisms: (1) chemisorption on internal walls at low concentrations and (2) silicide precipitation at concentrations exceeding the solid solubility. Experiments utilizing ion-beam analysis, cross-sectional transmission electron microscopy, and secondary ion mass spectrometry were performed to quantitatively characterize the gettering effects and to determine the free energies associated with the chemisorbed metal atoms as a function of temperature. Mathematical models utilizing these results have been developed to predict gettering behavior.

  4. Preparation of graphene on Cu foils by ion implantation with negative carbon clusters

    NASA Astrophysics Data System (ADS)

    Li, Hui; Shang, Yan-Xia; Zhang, Zao-Di; Wang, Ze-Song; Zhang, Rui; Fu, De-Jun

    2015-01-01

    We report on few-layer graphene synthesized on Cu foils by ion implantation using negative carbon cluster ions, followed by annealing at 950 °C in vacuum. Raman spectroscopy reveals IG/I2D values varying from 1.55 to 2.38 depending on energy and dose of the cluster ions, indicating formation of multilayer graphene. The measurements show that the samples with more graphene layers have fewer defects. This is interpreted by graphene growth seeded by the first layers formed via outward diffusion of C from the Cu foil, though nonlinear damage and smoothing effects also play a role. Cluster ion implantation overcomes the solubility limit of carbon in Cu, providing a technique for multilayer graphene synthesis. Project supported by the National Natural Science Foundation of China (Grant Nos. 11105100, 11205116, and 11375135) and the State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, China (Grant No. AWJ-M13-03).

  5. Switching the in-plane easy axis by ion implantation in rare earth based magnetic films.

    PubMed

    Buckingham, A R; Wang, D; Stenning, G B G; Bowden, G J; Nandhakumar, I; Ward, R C C; de Groot, P A J

    2013-02-27

    Ar(+) ions have been implanted into Laves phase epitaxial thin films of YFe(2) and DyFe(2). Magneto-optical Kerr effect and vibrating sample magnetometry experiments show that the easy and hard axes of magnetization in both materials rotate through an in-plane angle of 90°, whilst the strength of the magnetic anisotropy remains unaltered. This is supported by OOMMF computational modelling. Atomic force microscopy confirms that the film roughness is not affected by implanted ions. X-ray diffraction data show that the lattice parameter expands upon ion implantation, corresponding to a release of strain throughout the entire film following implantation with a critical fluence of 10(17) Ar(+) ions cm(-2). The anisotropy of the films is linked to the strain and from these data it is concluded that the source of anisotropy alters from one where magnetoelastic and magnetocrystalline effects compete to one which is governed solely by magnetocrystalline effects. The ability to locally tune the source of magnetic anisotropy without affecting the film surface and without inducing or eliminating anisotropy could be important in the fabrication of high density magnetic data storage media, spintronic devices and magneto-optical materials.

  6. Improving low-energy boron/nitrogen ion implantation in graphene by ion bombardment at oblique angles

    NASA Astrophysics Data System (ADS)

    Bai, Zhitong; Zhang, Lin; Liu, Ling

    2016-04-01

    Ion implantation is a widely adopted approach to structurally modify graphene and tune its electrical properties for a variety of applications. Further development of the approach requires a fundamental understanding of the mechanisms that govern the ion bombardment process as well as establishment of key relationships between the controlling parameters and the dominant physics. Here, using molecular dynamics simulations with adaptive bond order calculations, we demonstrate that boron and nitrogen ion bombardment at oblique angles (particularly at 70°) can improve both the productivity and quality of perfect substitution by over 25%. We accomplished this by systematically analyzing the effects of the incident angle and ion energy in determining the probabilities of six distinct types of physics that may occur in an ion bombardment event, including reflection, absorption, substitution, single vacancy, double vacancy, and transmission. By analyzing the atomic trajectories from 576 000 simulations, we identified three single vacancy creation mechanisms and four double vacancy creation mechanisms, and quantified their probability distributions in the angle-energy space. These findings further open the door for improved control of ion implantation towards a wide range of applications of graphene.Ion implantation is a widely adopted approach to structurally modify graphene and tune its electrical properties for a variety of applications. Further development of the approach requires a fundamental understanding of the mechanisms that govern the ion bombardment process as well as establishment of key relationships between the controlling parameters and the dominant physics. Here, using molecular dynamics simulations with adaptive bond order calculations, we demonstrate that boron and nitrogen ion bombardment at oblique angles (particularly at 70°) can improve both the productivity and quality of perfect substitution by over 25%. We accomplished this by systematically

  7. I. Heteroepitaxy on Silicon. I. Ion Implantation in Silicon and Heterostructures

    NASA Astrophysics Data System (ADS)

    Bai, Gang

    The themes of this thesis, heteroepitaxy and ion implantation, are two areas that have been very actively researched in the last two decades. Heterostructures made of III-V compound semiconductors by MBE and OMVPE have been used extensively in the fabrication of optoelectronics devices such as high-speed transistors and semiconductor lasers. Heterostructures on Si, which is the focus of part I of this thesis, have the advantage of compatibility with Si-based VLSI and promise to have impact on the microelectronics industry. Studies on the structural, elastic, thermal, and electrical properties of heteroepitaxial CoSi_2, ReSi _2, and GeSi films grown on Si constitute the backbone of this thesis. Some new characteristics of heterostructures were discovered as a result of this investigation. Among them are the observation and modeling of misorientation effects on an epitaxial film grown on a vicinal substrate; the misorientation induced by interfacial misfit dislocation arrays; the experimental measurements and phenomenological analysis of thermal strain, dislocation generation, and strain relaxation; and illustrative measurements of elastic, thermal, and structural properties of epitaxial films. Ion implantation is an important process in the fabrication of integrated circuits. The second part of this thesis deals with the production and annealing of damage produced by ion implantation in semiconductors. The defect production, stability, microstructure, and the induced strain in implanted bulk Si crystals were quantitatively investigated as a function of ion species, dose, and implantation temperature. Many new features, such as the rapid rise of damage near the amorphization threshold, the correlation between the strain and defect concentration, and the scaling behavior of the damage with ion species and implantation temperature, are revealed. The last chapter concerns the effects of ion implantation in CoSi_2, ReSi_2 , and GeSi/Si heterostructures, which is a

  8. [Studies on the breeding by ion implantation and cultivation of mycophenolic acid producing strain].

    PubMed

    Liu, Mei; Zhang, Peng; Cui, Xiao-Lan; Ren, Xiao; Zhang, Hua

    2006-10-01

    Mycophenolic acid is produced by aerobic fermentation of several Penicillium species. It has a broad spectrum of activity like antitumor activity, antiviral, anti-psoriatic, immunosuppressive and anti-inflammatory activity. It also exhibits antibacterial and antifungal activities. The immunosuppressive effect of MPA has been important in treatment of organ rejection after organ transplant surgery. There is a continuous need to find improved process for efficiently obtaining superior MPA producing mutants. In recent years, the ion implantation technique has been widely applied in many fields and has been drawn morn concern. However there is no report in the field of mutational breeding of MPA producing strain. Penicillium brevicompactum M-51 was derived from MPA producing strain F-663 by varied mutational methods including U.V. and microwave irradiation. In the process of increasing the production of MPA from P. brevicompactum M-51, a mutant strain M-163 was obtained by means of N+ ion implantation. An decline-increase-decline tendency of strain survival rates was observed when the strain was implanted by N+ ion with dose from 20 2.6 x 10(13) ions/cm2 to 180 x 2.6 x 10(13) ions/cm2 under implantation energy 15 keV. It apparently appeared "saddle shape". And under the implantation dose of 140 x 2.6 x 10(13) ions/cm2, the variation rate and the positive variation rate of the strain had reached the highest values 88.9% and 63.4%, respectively. The HPLC results showed that MPA yield of P. brevicompactum M-163 was improved by 30.1%, and its productivity was rather stable through successive transfer of cultures. The effect of seed growth time on yield of MPA was studied, and the best seed age was 24h after incubation. In the mean time, the fermentative condition of M-163 was studied through orthogonal design. The major ingredients being investigated included carbon and nitrogen sources. Finally the optimized fermentation medium was obtained. The yield of MPA reached 2819g

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. 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

  17. 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.

  18. Very low and broad threshold voltage fluctuation caused by ion implantation to silicon-on-insulator triple-gate fin-type field effect transistor using three-dimensional process and device simulations

    NASA Astrophysics Data System (ADS)

    Tsutsumi, Toshiyuki

    2017-06-01

    The threshold voltage (V th) fluctuation induced by the ion implantation to the source and drain extensions (SDE) of a silicon-on-insulator (SOI) triple-gate (tri-gate) fin-type field-effect transistor (FinFET) was analyzed for the first time with the use of realistic positional information of discretely doped ions by both three-dimensional (3D) process and device simulations. Interestingly, it was found that the V th fluctuation induced by SDE ion implantation has a very low and broad distribution on the low-V th side even in the case of a robust device structure such as SOI tri-gate FinFET. Furthermore, for the first time, it was quantitatively demonstrated using a proposed cluster percolation model that the origin of the very low and broad V th fluctuation is the conductive percolation among unintentionally doped ions in the channel region of the device. These results would contribute to the realization of robust transistors.

  19. 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.

  20. Some properties of near-surface layer of graded-gap MBE HgCdTe after boron ion implantation

    NASA Astrophysics Data System (ADS)

    Voitsekhovskii, A. V.; Nesmelov, S. N.; Dzyadukh, S. M.; Izhnin, I. I.

    2017-05-01

    The effect of ion implantation of boron ions with an energy of 100 keV and a dose of (1-6)×1015 cm-2 in the MBE HgCdTe films on the characteristics of the MIS structures based on these films was investigated. The changes of the conductivity type in the near-surface layer of HgCdTe after ion implantation of boron and etching by ions of argon were detected. The concentrations of the major charge carriers in the near-surface layer of the epitaxial films after ion implantation and after ion etching were close to 5.88×1016 cm-3 and 2.47×1017 cm-3, respectively.

  1. 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.

  2. 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.

  3. 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

  4. The use of an ion-beam source to alter the surface morphology of biological implant materials

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.

    1978-01-01

    An electron bombardment, ion thruster was used as a neutralized-ion beam sputtering source to texture the surfaces of biological implant materials. Scanning electron microscopy was used to determine surface morphology changes of all materials after ion-texturing. Electron spectroscopy for chemical analysis was used to determine the effects of ion texturing on the surface chemical composition of some polymers. Liquid contact angle data were obtained for ion textured and untextured polymer samples. Results of tensile and fatigue tests of ion-textured metal alloys are presented. Preliminary data of tissue response to ion textured surfaces of some metals, polytetrafluoroethylene, alumina, and segmented polyurethane were obtained.

  5. In vitro prominent bone regeneration by release zinc ion from Zn-modified implant

    SciTech Connect

    Yusa, Kazuyuki; Yamamoto, Osamu; Fukuda, Masayuki; Koyota, Souichi; Koizumi, Yukio; Sugiyama, Toshihiro

    2011-08-26

    Highlights: {yields} We isolated the Zn{sup 2+} ions (eluted Zn{sup 2+} ion; EZ) from zinc-incorporated titanium implant. {yields} The EZ promoted the cell viability in hBMCs. {yields} The EZ stimulated preosteoblast and osteoblast marker gene expression in hBMCs. {yields} The hBMCs supplemented with EZ showed typically cell morphology when osteoblast maturing. {yields} It is revealed that the EZ also stimulates the calcium deposition of hBMCs. -- Abstract: Zinc is one of the trace elements which induce the proliferation and the differentiation of the osteoblast. In the previous study, we found that zinc ions (Zn{sup 2+} ion)-releasing titanium implants had excellent bone fixation using a rabbit femurs model. In this study, we isolated the Zn{sup 2+} ions (eluted Zn{sup 2+} ion; EZ) released from the implant surface, and evaluated the effect of EZ on the osteogenesis of human bone marrow-derived mesenchymal cells (hBMCs). In the result, it was found that the EZ stimulated cell viability, osteoblast marker gene (type I collagen, osteocalcin (OC), alkaline phosphatase (ALP) and bone sialoprotein (BSP)) expressions and calcium deposition in hBMCs.

  6. 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

  7. The effect of Be/+/ ion implanted exponential and uniform impurity profiles on the electrical characteristics of GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Vaidyanathan, K. V.; Walker, G. H.

    1974-01-01

    The high surface recombination velocity is the major deterrent to obtaining efficient GaAs solar cells. If, however, an electric field is built in at the surface, the carriers will be swept away from the surface thus minimizing the surface recombination velocity problem. It has been previously shown theoretically that an exponential impurity distribution in the doped region of the cell results in a built-in electric field. Ion implantation was used to produce solar cells with an exponential impurity profile and cells with uniform profiles. It is shown that cells with an exponential impurity profile have higher open-circuit voltage, fill factors, and spectral response than those with a uniform impurity profile.

  8. The effect of Be/+/ ion implanted exponential and uniform impurity profiles on the electrical characteristics of GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Vaidyanathan, K. V.; Walker, G. H.

    1974-01-01

    The high surface recombination velocity is the major deterrent to obtaining efficient GaAs solar cells. If, however, an electric field is built in at the surface, the carriers will be swept away from the surface thus minimizing the surface recombination velocity problem. It has been previously shown theoretically that an exponential impurity distribution in the doped region of the cell results in a built-in electric field. Ion implantation was used to produce solar cells with an exponential impurity profile and cells with uniform profiles. It is shown that cells with an exponential impurity profile have higher open-circuit voltage, fill factors, and spectral response than those with a uniform impurity profile.

  9. Wafer-scale synthesis of multi-layer graphene by high-temperature carbon ion implantation

    SciTech Connect

    Kim, Janghyuk; Lee, Geonyeop; Kim, Jihyun

    2015-07-20

    We report on the synthesis of wafer-scale (4 in. in diameter) high-quality multi-layer graphene using high-temperature carbon ion implantation on thin Ni films on a substrate of SiO{sub 2}/Si. Carbon ions were bombarded at 20 keV and a dose of 1 × 10{sup 15 }cm{sup −2} onto the surface of the Ni/SiO{sub 2}/Si substrate at a temperature of 500 °C. This was followed by high-temperature activation annealing (600–900 °C) to form a sp{sup 2}-bonded honeycomb structure. The effects of post-implantation activation annealing conditions were systematically investigated by micro-Raman spectroscopy and transmission electron microscopy. Carbon ion implantation at elevated temperatures allowed a lower activation annealing temperature for fabricating large-area graphene. Our results indicate that carbon-ion implantation provides a facile and direct route for integrating graphene with Si microelectronics.

  10. Optical properties of K9 glass waveguides fabricated by using carbon-ion implantation

    NASA Astrophysics Data System (ADS)

    Liu, Chun-Xiao; Wei, Wei; Fu, Li-Li; Zhu, Xu-Feng; Guo, Hai-Tao; Li, Wei-Nan; Lin, She-Bao

    2016-07-01

    K9 glass is a material with promising properties that make it attractive for optical devices. Ion implantation is a powerful technique to form waveguides with controllable depth and refractive index profile. In this work, optical planar waveguide structures were fabricated in K9 glasses by using 6.0-MeV C3+-ion implantation with a fluence of 1.0 × 1015 ions/cm2. The effective refractive indices of the guided modes were measured by using a prism-coupling system. The refractive index change in the ion-irradiated region was simulated by using the intensity calculation method. The modal intensity profile of the waveguide was calculated and measured by using the finite difference beam propagation method and the end-face coupling technique, respectively. The transmission spectra before and after the implantation showed that the main absorption band was not influenced by the low fluence dopants. The optical properties of the carbon-implanted K9 glass waveguides show promise for use as integrated photonic devices.

  11. Enhanced electron field emission properties of conducting ultrananocrystalline diamond films after Cu and Au ion implantation.

    PubMed

    Sankaran, Kamatchi Jothiramalingam; Chen, Huang-Chin; Panda, Kalpataru; Sundaravel, Balakrishnan; Lee, Chi-Young; Tai, Nyan-Hwa; Lin, I-Nan

    2014-04-09

    The effects of Cu and Au ion implantation on the structural and electron field emission (EFE) properties of ultrananocrystalline diamond (UNCD) films were investigated. High electrical conductivity of 186 (Ω•cm)(-1) and enhanced EFE properties with low turn-on field of 4.5 V/μm and high EFE current density of 6.70 mA/cm(2) have been detected for Au-ion implanted UNCD (Au-UNCD) films that are superior to those of Cu-ion implanted UNCD (Cu-UNCD) ones. Transmission electron microscopic investigations revealed that Au-ion implantation induced a larger proportion of nanographitic phases at the grain boundaries for the Au-UNCD films in addition to the formation of uniformly distributed spherically shaped Au nanoparticles. In contrast, for Cu-UNCD films, plate-like Cu nanoparticles arranged in the row-like pattern were formed, and only a smaller proportion of nanographite phases along the grain boundaries was induced. From current imaging tunneling spectroscopy and local current-voltage curves of scanning tunneling spectroscopic measurements, it is observed that the electrons are dominantly emitted from the grain boundaries. Consequently, the presence of nanosized Au particles and the induction of abundant nanographitic phases in the grain boundaries of Au-UNCD films are believed to be the authentic factors, ensuing in high electrical conductivity and outstanding EFE properties of the films.

  12. Single crystalline BaTiO3 thin films synthesized using ion implantation induced layer transfer

    NASA Astrophysics Data System (ADS)

    Park, Young-Bae; Diest, Kenneth; Atwater, Harry A.

    2007-10-01

    Layer transfer of BaTiO3 thin films onto silicon-based substrates has been investigated. Hydrogen and helium ions were co-implanted to facilitate ion-implantation-induced layer transfer of films from BaTiO3 single crystals. From thermodynamic equilibrium calculations, we suggest that the dominant species during cavity nucleation and growth are H2, H+, H2O, Ba2+ and Ba-OH, and that the addition of hydrogen to the Ba-Ti-O system can effectively suppress volatile oxide formation during layer transfer and subsequent annealing. After ion implantation, BaTiO3 layers contain microstructural defects and hydrogen precipitates in the lattice, but after layer transfer, the single crystal is found to be stoichiometric. Using direct wafer bonding and layer splitting, single crystal BaTiO3 thin films were transferred onto amorphous Si3N4 and Pt substrates. Micro-Raman spectroscopy indicated that the density of defects generated by ion implantation in BaTiO3 can be significantly reduced during post-transfer annealing, returning the transferred layer to its single crystal state. Characterization using piezoresponse force microscopy shows that the layer transferred thin films are ferroelectric, with domain structures and piezoresponse characteristics similar to that of bulk crystals.

  13. A Mutant of Bacillus Subtilis with High-Producing Surfactin by Ion Beam Implantation

    NASA Astrophysics Data System (ADS)

    Liu, Qingmei; Yuan, Hang; Wang, Jun; Gong, Guohong; Zhou, Wei; Fan, Yonghong; Wang, Li; Yao, Jianming; Yu, Zengliang

    2006-07-01

    In order to generate a mutant of Bacillus subtilis with enhanced surface activity through low energy nitrogen ion beam implantation, the effects of energy and dose of ions implanted were studied. The morphological changes in the bacteria were observed by scanning electron microscope (SEM). The optimum condition of ions implantation, 20 keV of energy and 2.6×1015N+/cm2 in dose, was determined. A mutant, B.s-E-8 was obtained, whose surface activity of 50-fold and 100-fold diluted cell-free Landy medium was as 5.6-fold and 17.4-fold as the wild strain. The microbial growth and biosurfactant production of both the mutant and the wild strain were compared. After purified by ultrafiltration and SOURCE 15PHE, the biosurfactant was determined to be a complex of surfactin family through analysis of electrospray ionization mass spectrum (ESI/MS) and there was an interesting finding that after the ion beam implantation the intensities of the components were different from the wild type strain.

  14. Structure and properties of ion-implanted Al sub 2 O sub 3

    NASA Astrophysics Data System (ADS)

    McHargue, C. J.; Farlow, G. C.; White, C. W.; Appleton, B. R.; Angelini, P.; Naramoto, H.

    1984-11-01

    The effects of implantation parameters temperature (77 to 640 K), ion species (Cr, Zr, Nb, Al+C, Xe), and fluence (1 x 10(14) to 1 x 10(17) ions.cm(-2)) on the structure and surface hardness of Al2O3 were studied. Low temperatures favor the rapid accumulation of damage and formation of an amorphous layer. Except for zirconium, fluences in excess of 1 x 10(17) ions/cm (-2) are required to amorphize Al2O3 at 300 K. The amorphous phase has a hardness about 65% of that of the crystalline phase.

  15. Hydrophilic property by contact angle change of ion implanted polycarbonate

    SciTech Connect

    Lee, Chan Young; Kil, Jae Keun

    2008-02-15

    In this study, ion implantation was performed onto a polymer, polycarbonate (PC), in order to investigate surface hydrophilic property through contact angle measurement. PC was irradiated with N, Ar, and Xe ions at the irradiation energy of 20-50 keV and the dose range of 5x10{sup 15}, 1x10{sup 16}, 7x10{sup 16} ions/cm{sup 2}. The contact angle of water was estimated by means of the sessile drop method and was reduced with increasing fluence and ion mass but increased with increasing implanted energy. The changes of chemical and structural properties are discussed in view of Furier transform infrared and x-ray photoelectron spectroscopy, which shows increasing C-O bonding and C-C bonding. The surface roughness examined by atomic force microscopy measurement changed smoothly from 3.59 to 2.22 A as the fluence increased. It is concluded that the change in wettability may be caused by surface carbonization and oxidation as well as surface roughness.

  16. FeN foils by nitrogen ion-implantation

    SciTech Connect

    Jiang, Yanfeng; Wang, Jian-Ping; Al Mehedi, Md; Fu, Engang; Wang, Yongqiang

    2014-05-07

    Iron nitride samples in foil shape (free standing, 500 nm in thickness) were prepared by a nitrogen ion-implantation method. To facilitate phase transformation, the samples were bonded on the substrate followed by a post-annealing step. By using two different substrates, single crystal Si and GaAs, structural and magnetic properties of iron nitride foil samples prepared with different nitrogen ion fluences were characterized. α″-Fe{sub 16}N{sub 2} phase in iron nitride foil samples was obtained and confirmed by the proposed approach. A hard magnetic property with coercivity up to 780 Oe was achieved for the FeN foil samples bonded on Si substrate. The feasibility of using nitrogen ion implantation techniques to prepare FeN foil samples up to 500 nm thickness with a stable martensitic phase under high ion fluences has been demonstrated. A possible mechanism was proposed to explain this result. This proposed method could potentially be an alternative route to prepare rare-earth-free FeN bulk magnets by stacking and pressing multiple free-standing thick α″-Fe{sub 16}N{sub 2} foils together.

  17. Hydrophilic property by contact angle change of ion implanted polycarbonate.

    PubMed

    Lee, Chan Young; Kil, Jae Keun

    2008-02-01

    In this study, ion implantation was performed onto a polymer, polycarbonate (PC), in order to investigate surface hydrophilic property through contact angle measurement. PC was irradiated with N, Ar, and Xe ions at the irradiation energy of 20-50 keV and the dose range of 5x10(15), 1x10(16), 7x10(16) ions/cm(2). The contact angle of water was estimated by means of the sessile drop method and was reduced with increasing fluence and ion mass but increased with increasing implanted energy. The changes of chemical and structural properties are discussed in view of Furier transform infrared and x-ray photoelectron spectroscopy, which shows increasing C-O bonding and C-C bonding. The surface roughness examined by atomic force microscopy measurement changed smoothly from 3.59 to 2.22 A as the fluence increased. It is concluded that the change in wettability may be caused by surface carbonization and oxidation as well as surface roughness.

  18. Hydrophilic property by contact angle change of ion implanted polycarbonatea)

    NASA Astrophysics Data System (ADS)

    Lee, Chan Young; Kil, Jae Keun

    2008-02-01

    In this study, ion implantation was performed onto a polymer, polycarbonate (PC), in order to investigate surface hydrophilic property through contact angle measurement. PC was irradiated with N, Ar, and Xe ions at the irradiation energy of 20-50keV and the dose range of 5×1015, 1×1016, 7×1016ions/cm2. The contact angle of water was estimated by means of the sessile drop method and was reduced with increasing fluence and ion mass but increased with increasing implanted energy. The changes of chemical and structural properties are discussed in view of Furier transform infrared and x-ray photoelectron spectroscopy, which shows increasing C O bonding and C C bonding. The surface roughness examined by atomic force microscopy measurement changed smoothly from 3.59to2.22Å as the fluence increased. It is concluded that the change in wettability may be caused by surface carbonization and oxidation as well as surface roughness.

  19. Study on hemocompatibility and corrosion behavior of ion implanted TiNi shape memory alloy and Co-based alloys.

    PubMed

    Liang, Chenghao; Huang, Naibao

    2007-10-01

    Biomedical TiNi shape memory alloy and Co-based alloys were ion implanted, and corrosion resistance and hemocompatibility of these had been investigated with electrochemical method, dynamic clotting time, and hemolysis rate tests. The results indicated that the electrochemical stability and anodic polarization behavior of the materials were improved significantly after ion implantation. When TiNi, Co-based alloys were implanted Mo + C and Ti + C, respectively, the corrosion potentials were enhanced more than 200 mV, passive current densities decreased, and passive ranges were broadened. Dynamic clotting time of the ion implanted substances was prolonged and hemolysis rate decreased. All the results pointed out that corrosion resistance and hemocompatibility of the alloys were improved by ion implantation, and effects of dual implantation was better than that of C single implantation. X-ray diffraction analysis of the alloys after dual implantation revealed that TiC, Mo(2)C, Mo(9)Ti(4), and Mo appeared on the surface of TiNi alloy, and CoC(x), Co(3)Ti, TiC, and TiO on the surface of Co-based alloys. These phases dispersing on the alloy surface formed amorphous film, prevented dissolving of alloy elements and improved the corrosion resistance and hemocompatibility of the alloys.

  20. Thermal annealing behavior of nano-size metal-oxide particles synthesized by ion implantation in Fe-Cr alloy

    NASA Astrophysics Data System (ADS)

    Zheng, C.; Gentils, A.; Ribis, J.; Borodin, V. A.; Descoins, M.; Mangelinck, D.; Dalle, F.; Arnal, B.; Delauche, L.

    2017-05-01

    Oxide dispersion strengthened (ODS) steels are promising structural materials for the next generation nuclear reactors, as well as fusion facilities. The detailed understanding of the mechanisms involved in the precipitation of nano-oxides during ODS steel production would strongly contribute to the improvement of the mechanical properties and the optimization of manufacturing of ODS steels, with a potentially strong economic impact for their industrialization. A useful tool for the experimental study of nano-oxide precipitation is ion implantation, a technique that is widely used to synthesize precipitate nanostructures in well-controlled conditions. Earlier, we have demonstrated the feasibility of synthesizing aluminum-oxide particles in the high purity Fe-10Cr alloy by consecutive implantation with Al and O ions at room temperature. This paper describes the effects of high-temperature annealing after the ion implantation stage on the development of the aluminum based oxide nanoparticle system. Using transmission electron microscopy and atom probe tomography experiments, we demonstrate that post-implantation heat treatment induces the growth of the nano-sized oxides in the implanted region and nucleation of new oxide precipitates behind the implantation zone as a result of the diffusion driven broadening of implant profiles. A tentative scenario for the development of metal-oxide nano-particles at both ion implantation and heat treatment stages is suggested based on the experimental observations.

  1. Investigation of trap properties in high-k/metal gate p-type metal-oxide-semiconductor field-effect-transistors with aluminum ion implantation using random telegraph noise analysis

    SciTech Connect

    Kao, Tsung-Hsien; Chang, Shoou-Jinn Fang, Yean-Kuen; Huang, Po-Chin; Wu, Chung-Yi; Wu, San-Lein

    2014-08-11

    In this study, the impact of aluminum ion implantation (Al I/I) on random telegraph noise (RTN) in high-k/metal gate (HK/MG) p-type metal-oxide-semiconductor field-effect-transistors (pMOSFETs) was investigated. The trap parameters of HK/MG pMOSFETs with Al I/I, such as trap energy level, capture time and emission time, activation energies for capture and emission, and trap location in the gate dielectric, were determined. The configuration coordinate diagram was also established. It was observed that the implanted Al could fill defects and form a thin Al{sub 2}O{sub 3} layer and thus increase the tunneling barrier height for holes. It was also observed that the trap position in the Al I/I samples was lower due to the Al I/I-induced dipole at the HfO{sub 2}/SiO{sub 2} interface.

  2. 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.

  3. Cathodic shift of onset potential for water oxidation of WO3 photoanode by Zr+ ions implantation

    NASA Astrophysics Data System (ADS)

    Wu, Hengyi; Ren, Feng; Xing, Zhuo; Zheng, Xudong; Wu, Liang; Jiang, Changzhong

    2017-02-01

    Tungsten trioxide is one of the most widely studied semiconductors for photoelectrochemical water splitting. However, its onset potential is too positive. In a photoelectrochemical system, a low onset potential and a high photocurrent for a photoanode are important for enhancing the efficiency of water splitting. It is an effective way to adjust the onset potential by changing the conduction and valence band level. Doping is a powerful way to alter the positions of the energy levels of semiconductors to improve their photoelectrochemical performance. In this paper, we present a method of ion implantation to alter the energy levels by implanting Zr+ ions into WO3. Cathodic shifts of the photocurrent onset potential for water oxidation are achieved. The systematic studies show that ion implantation followed by thermal annealing treatment can form substitutional Zr4+ in WO3. The upward shifts of the conduction band and valence band lead to the cathodic shifts of the onset potential. Two combined factors lead to the upward shift of the conduction band. One is strain induced after doping in the lattices. Another is due to the higher energy level of the Zr 4d orbital than the W 5d orbital. Meanwhile, the oxygen vacancy introduced during the ion implantation can cause an upward shift the valence band maximum. The results indicate that the upward shifts of the conduction band minimum and valence band maximum are good for the photoelectrochemical water splitting. It also shows that an ion implantation technique combined with thermal annealing could be an effective way to enhance the performance of the photoanode for water splitting.

  4. Monolithic integration of a DFB superlattice laser using high energy ion implantation

    NASA Astrophysics Data System (ADS)

    Pronko, P. P.; Rai, A. K.; Ingram, D.; McCormick, A. W.; Ezis, A.

    1991-02-01

    The objective of this research is to develop the use of high energy (MeV) and medium energy (keV) ion beams for the purpose of selectively modifying the optical properties of superlattice systems consisting of mixed III-V compound semiconductors. In particular, the research was directed at the AlGaAs/GaAs multilayer superlattice system and its potential use in fabricating a monolithically integrated distributed feedback laser for use in optoelectronic circuits. The optical properties of such semiconductor superlattice systems have been shown to be sensitive to ion bombardment and its associated implantation and mixing process. The use of ion beams makes it possible to modify these structures through selective masking so that optical elements such as lasers, waveguides, and switches could be fabricated under the constraints imposed by monolithic integration. In particular, investigations were made into the effects of implantation controlled disordering of AlGaAs and GaAs through impurity, defect, and ion beam mixing effects. The results of this work were applied to the development and fabrication of an ion implanted distributed feedback (DFB) type laser in a multilayer superlattice system.

  5. Material synthesis for silicon integrated-circuit applications using ion implantation

    NASA Astrophysics Data System (ADS)

    Lu, Xiang

    of microscopic images. The underlying hydrogen profiles for between 250sp°C and 500sp°C annealing are characterized by SIMS and HFS experiments. An ideal gas law model calculation suggests that the internal pressure of molecular hydrogen filled microcavities is in the range of Giga-Pascal, high enough to break the silicon crystal bond. A dose threshold which prevents cleavage is observed at 1.6× 10sp{17} cmsp{-2} for 40 kV hydrogen implantation. A initial defect, in a silicon substrate, induced by a hydrogen microcavity is modeled as a circular crack which is embedded at a certain depth from the top silicon surface. A two-dimensional finite element model is made to calculate energy release rate along the crack surfaces. This numerical model predicts that the energy release rate is sufficient to overcome the silicon fracture toughness. The model further identifies the factors that can enhance the energy release rate. Ion-Cut SOI wafer fabrication technique is implemented using Pm. The hydrogen implantation rate, which is independent of the wafer size, is considerably higher than that of conventional implantation. The simple Pm reactor setup and its compatibility with cluster-tool IC manufacturing system offer other Ion-Cut process optimization opportunities. The feasibility of Pm Ion-Cut process has been demonstrated with successful fabrication of SOI structures. The hydrogen plasma can be optimized so that only one ion species is dominant in concentration, with minimal effect on the Ion-Cut process by the residual ion components. We have also demonstrated the feasibility of performing Ion-Cut using Pm in helium plasma.

  6. Hexagonal cobalt carbide formed by carbon ion implantation

    NASA Astrophysics Data System (ADS)

    Liu, B. X.; Wang, J.; Fang, Z. Z.

    1991-05-01

    Thin films of ferromagnetic metals, i.e., bcc Fe, hcp Co, and fcc Ni, were subjected to 50-keV carbon ion implantation at room temperature. At the dose of 2.5×1017 ions/cm2, the formation of hexagonal Fe3C and Ni3C phases was confirmed by transmission electron microscopy selected area electron diffraction patterns; and more interestingly a similar pattern for Co was also observed for the first time. The phase was identified as hexagonal Co3C with a=2.685 Å and c=4.335 Å based on the spacings and intensities of the diffraction rings. The carbide formation was also confirmed by Auger electron spectra. The stoichiometry of the hexagonal structure may be extended in the range of Co3-2C as estimated from the experiments performed up to the dose of 9×1017 ions/cm2.

  7. Evaluation of the ion implantation process for production of solar cells from silicon sheet materials

    NASA Technical Reports Server (NTRS)

    Spitzer, M. B.

    1983-01-01

    For the ion implantation tooling was fabricated with which to hold dendritic web samples. This tooling permits the expeditious boron implantation of the back to form the back surface field (BSF). Baseline BSF web cells were fabricated.

  8. Doping of GaN by ion implantation: Does It Work?

    SciTech Connect

    Suvkhanov, A.; Wu, W.; Price, K.; Parikh, N.; Irene, E.; Hunn, J.; Thomson, D.; Davis, R.F.; Krasnobaev, L.

    1998-04-01

    Epitaxially grown GaN by metal organic chemical vapor deposition (MOCVD) on SiC were implanted with 100 keV Si{sup +} (for n-type) and 80 keV Mg{sup +} (for p-type) with various fluences from 1 {times} 10{sup 12} to 7 {times} 10 {sup 15} ions/cm{sup 2} at liquid nitrogen temperature (LT), room temperature (RT), and 700 C (HT). High temperature (1,200 C and 1,500 C) annealing was carried out after capping the GaN with epitaxial AlN by MOCVD to study damage recovery. Samples were capped by a layer of AlN in order to protect the GaN surface during annealing. Effects of implant temperature, damage and dopant activation are critically studied to evaluate a role of ion implantation in doping of GaN. The damage was studied by Rutherford Backscattering/Channeling, spectroscopic ellipsometry and photoluminescence. Results show dependence of radiation damage level on temperature of the substrate during implantation: implantations at elevated temperatures up to 550 C decrease the lattice disorder; hot implants above 550 C can not be useful in doping of GaN due to nitrogen loss from the surface. SE measurements have indicated very high sensitivity to the implantation damage. PL measurements at LT of 80 keV Mg{sup +} (5 {times} 10{sup 14} cm{sup 2}) implanted and annealed GaN showed two peaks: one {approximately} 100 meV and another {approximately} 140 meV away from the band edge.

  9. 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.

  10. Irradiation hardening of ODS ferritic steels under helium implantation and heavy-ion irradiation

    NASA Astrophysics Data System (ADS)

    Zhang, Hengqing; Zhang, Chonghong; Yang, Yitao; Meng, Yancheng; Jang, Jinsung; Kimura, Akihiko

    2014-12-01

    Irradiation hardening of ODS ferritic steels after multi-energy He-ion implantation, or after irradiation with energetic heavy ions including Xe and Bi-ions was investigated with nano-indentation technique. Three kinds of high-Cr ODS ferritic steels including the commercial MA956 (19Cr-3.5Al), the 16Cr-0.1Ti and the 16Cr-3.5Al-0.1Zr were used. Data of nano-hardness were analyzed with an approach based on Nix-Gao model. The depth profiles of nano-hardness can be understood by the indentation size effect (ISE) in specimens of MA956 implanted with multi-energy He-ions or irradiated with 328 MeV Xe ions, which produced a plateau damage profile in the near-surface region. However, the damage gradient overlaps the ISE in the specimens irradiated with 9.45 Bi ions. The dose dependence of the nano-hardness shows a rapid increase at low doses and a slowdown at higher doses. An 1/2-power law dependence on dpa level is obtained. The discrepancy in nano-hardness between the helium implantation and Xe-ion irradiation can be understood by using the average damage level instead of the peak dpa level. Helium-implantation to a high dose (7400 appm/0.5 dpa) causes an additional hardening, which is possibly attributed to the impediment of motion dislocations by helium bubbles formed in high concentration in specimens.

  11. 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.

  12. Microchemical and microstructural changes of Co cemented WC induced by ion implantation

    NASA Astrophysics Data System (ADS)

    Lin, W. L.; Sang, J. M.; Ding, X. J.; Xu, J.; Yuan, X. M.

    2002-04-01

    Changes in the microchemistry and microstructure of cobalt cemented tungsten carbide (WC-Co) hard alloy which were implanted with energetic Ta ions, with and without an additional C ion beam, have been investigated. Ion implantation was carried out at room temperature using a metal vapor vacuum arc source ion implanter. The extraction voltage and average current density of the ion beam was 45 kV and 50 μA/cm 2, respectively. The concentration depth profiles and microstructure of implanted the WC-Co alloy were analyzed by Rutherford backscattering spectroscopy, Auger electron spectroscopy, and glancing angle X-ray diffraction, respectively. The results showed that as compared with the control, there were no significant microstructural changes in the tungsten carbide phase of implanted WC-Co alloy substrate; both Ta implantation and Ta+C dual implantation induced a transformation from a metastable cubic form to a stable hcp form of cobalt binder phase.

  13. P-type doping of GaN(000\\bar{1}) by magnesium ion implantation

    NASA Astrophysics Data System (ADS)

    Narita, Tetsuo; Kachi, Tetsu; Kataoka, Keita; Uesugi, Tsutomu

    2017-01-01

    Magnesium ion implantation has been performed on a GaN(000\\bar{1}) substrate, whose surface has a high thermal stability, thus allowing postimplantation annealing without the use of a protective layer. The current-voltage characteristics of p-n diodes fabricated on GaN(000\\bar{1}) showed distinct rectification at a turn-on voltage of about 3 V, although the leakage current varied widely among the diodes. Coimplantation with magnesium and hydrogen ions effectively suppressed the leakage currents and device-to-device variations. In addition, an electroluminescence band was observed at wavelengths shorter than 450 nm for these diodes. These results provide strong evidence that implanted magnesium ions create acceptors in GaN(000\\bar{1}).

  14. Synthesis of graphene and graphene nanostructures by ion implantation and pulsed laser annealing

    SciTech Connect

    Wang, Xiaotie; Rudawski, Nicholas G.; Appleton, Bill R.; Berke, Kara; Hebard, Arthur F.; Venkatachalam, Dinesh K.; Elliman, Robert G.; Fridmann, Joel; Ren, Fan; Gila, Brent P.

    2016-07-14

    In this paper, we report a systematic study that shows how the numerous processing parameters associated with ion implantation (II) and pulsed laser annealing (PLA) can be manipulated to control the quantity and quality of graphene (G), few-layer graphene (FLG), and other carbon nanostructures selectively synthesized in crystalline SiC (c-SiC). Controlled implantations of Si{sup −} plus C{sup −} and Au{sup +} ions in c-SiC showed that both the thickness of the amorphous layer formed by ion damage and the doping effect of the implanted Au enhance the formation of G and FLG during PLA. The relative contributions of the amorphous and doping effects were studied separately, and thermal simulation calculations were used to estimate surface temperatures and to help understand the phase changes occurring during PLA. In addition to the amorphous layer thickness and catalytic doping effects, other enhancement effects were found to depend on other ion species, the annealing environment, PLA fluence and number of pulses, and even laser frequency. Optimum II and PLA conditions are identified and possible mechanisms for selective synthesis of G, FLG, and carbon nanostructures are discussed.

  15. Synthesis of graphene and graphene nanostructures by ion implantation and pulsed laser annealing

    NASA Astrophysics Data System (ADS)

    Wang, Xiaotie; Berke, Kara; Rudawski, Nicholas G.; Venkatachalam, Dinesh K.; Elliman, Robert G.; Fridmann, Joel; Hebard, Arthur F.; Ren, Fan; Gila, Brent P.; Appleton, Bill R.

    2016-07-01

    In this paper, we report a systematic study that shows how the numerous processing parameters associated with ion implantation (II) and pulsed laser annealing (PLA) can be manipulated to control the quantity and quality of graphene (G), few-layer graphene (FLG), and other carbon nanostructures selectively synthesized in crystalline SiC (c-SiC). Controlled implantations of Si- plus C- and Au+ ions in c-SiC showed that both the thickness of the amorphous layer formed by ion damage and the doping effect of the implanted Au enhance the formation of G and FLG during PLA. The relative contributions of the amorphous and doping effects were studied separately, and thermal simulation calculations were used to estimate surface temperatures and to help understand the phase changes occurring during PLA. In addition to the amorphous layer thickness and catalytic doping effects, other enhancement effects were found to depend on other ion species, the annealing environment, PLA fluence and number of pulses, and even laser frequency. Optimum II and PLA conditions are identified and possible mechanisms for selective synthesis of G, FLG, and carbon nanostructures are discussed.

  16. Photorefractive properties of ion-implanted waveguides in strontium barium niobate crystals

    NASA Astrophysics Data System (ADS)

    Kip, D.; Kemper, B.; Nee, I.; Pankrath, R.; Moretti, P.

    1997-10-01

    Planar optical waveguides were formed in cerium-doped strontium barium niobate single crystals (Sr0.61Ba0.39Nb2O6, SBN61), either by proton or helium ion implantation. Proton-implanted samples show a large increase of dark conductivity that reduces or even prevents the recording of refractive index gratings. For waveguides formed by helium implantation this effect is absent, and they can be used for efficient holographic recording. Photorefractive properties of the waveguides are investigated by two-beam coupling. After implantation with 2.0 MeV He+ and doses of (0.5-5)񺔗 cm-2, the samples have to be polarized again, because heating or charge effects at the crystals surface during the implantation process decreases or even reverses the effective electrooptic coefficients in the waveguiding layer. For repoled samples, we find logarithmic gain coefficients of up to 45 cm-1 with time constants for the build-up of the purely ?/2-shifted refractive index grating of the order of 1 ms for the blue lines of an Ar+ laser. Photoconductivity depends nonlinearly on light intensity with an exponent xƸ.55. With increasing implanted helium dose, both electronic and nuclear damage of the waveguiding layer grows, and the photorefractive properties of the waveguides are considerably degraded.

  17. Surface characterisation of Ga+ ion implanted ta-C thin films

    NASA Astrophysics Data System (ADS)

    Berova, M.

    2017-01-01

    Samples of thin film (d∼40nm) tetrahedral amorphous carbon (ta-C), deposited by filtered cathodic vacuum arc (FCVA), have been implanted with Ga+ at ion energy E = 20 keV and ion doses D=3.1014÷3.1015 cm-2. The induced structural modification of the implanted material results in a considerable change of its optical properties, best manifested by a significant shift of the optical absorption edge to lower photon energies. This shift is accompanied by a considerable increase of the absorption coefficient (photo-darkening effect) in the measured photon energy range (0.5÷3.0 eV). These effects could be attributed both to additional defect introduction and increased graphitization, as well as due to Ga colloids formation, as confirmed by electron microscopy analysis. Further nano-scale structural and electronic properties characterisation of the Ga+ implanted films has been carried out here using conductive atomic force microscopy (C-AFM) measurements. The observed properties modification results from the high concentration of introduced Ga+ atoms, which is of the order of those for the host element. The obtained optical contrast (between implanted and unimplanted film material) could be made use of in the area of high-density optical data storage by using focused Ga+ ion beams.

  18. 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.

  19. Stoichiometric disturbances in compound semiconductors due to ion implantation

    NASA Technical Reports Server (NTRS)

    Avila, R. E.; Fung, C. D.

    1986-01-01

    A method is developed to calculate the depth distribution of the local stoichiometric disturbance (SD) resulting from ion implantation in binary-compound substrates. The calculation includes first-order recoils considering projected range straggle of projectiles and recoils and lateral straggle of recoils. The method uses tabulated final-range statistics to infer the projectile range distributions at intermediate energies. This approach greatly simplifies the calculation with little compromise on accuracy as compared to existing procedures. As an illustration, the SD profile is calculated for implantation of boron, silicon, and aluminum in silicon carbide. The results for the latter case suggest that the SD may be responsible for otherwise unexplained distortions in the annealed aluminum profile. A comparison with calculations by other investigators using the Boltzmann transport equation shows good agreement.

  20. Ion implanted integrated Bragg gratings in SOI waveguides

    NASA Astrophysics Data System (ADS)

    Bulk, M. P.; Knights, A. P.; Jessop, P. E.

    2007-06-01

    We report the realization of a Bragg grating optical filter at telecommunication wavelengths in silicon-on-insulator (SOI) through the use of ion implantation induced refractive index modulation. Silicon self-irradiation damage accumulation results in an increase of the refractive index to a saturated value, upon amorphization, of approximately 3.75. This makes it an interesting candidate for passive gratings as the silicon retains a planar surface, making it ideal for further processing. Monte Carlo simulations and coupled mode theory demonstrate the viability of the approach. Planar implanted SOI waveguides showed extinction ratios of -5 dB for TE and -2 dB for TM. An annealing study suggests complete amorphization was not achieved and future results should be improved dramatically.