Science.gov

Sample records for advanced ion implantation

  1. Dopant profile engineering of advanced Si MOSFET's using ion implantation

    NASA Astrophysics Data System (ADS)

    Stolk, P. A.; Ponomarev, Y. V.; Schmitz, J.; van Brandenburg, A. C. M. C.; Roes, R.; Montree, A. H.; Woerlee, P. H.

    1999-01-01

    Ion implantation has been used to realize non-uniform, steep retrograde (SR) dopant profiles in the active channel region of advanced Si MOSFET's. After defining the transistor configuration, SR profiles were formed by dopant implantation through the polycrystalline Si gate and the gate oxide (through-the-gate, TG, implantation). The steep nature of the as-implanted profile was retained by applying rapid thermal annealing for dopant activation and implantation damage removal. For NMOS transistors, TG implantation of B yields improved transistor performance through increased carrier mobility, reduced junction capacitances, and reduced susceptibility to short-channel effects. Electrical measurements show that the gate oxide quality is not deteriorated by the ion-induced damage, demonstrating that transistor reliability is preserved. For PMOS transistors, TG implantation of P or As leads to unacceptable source/drain junction broadening as a result of transient enhanced dopant diffusion during thermal activation.

  2. Ion Implantation

    NASA Astrophysics Data System (ADS)

    Langouche, G.; Yoshida, Y.

    In this tutorial we describe the basic principles of the ion implantation technique and we demonstrate that emission Mössbauer spectroscopy is an extremely powerful technique to investigate the atomic and electronic configuration around implanted atoms. The physics of dilute atoms in materials, the final lattice sites and their chemical state as well as diffusion phenomena can be studied. We focus on the latest developments of implantation Mössbauer spectroscopy, where three accelerator facilities, i.e., Hahn-Meitner Institute Berlin, ISOLDE-CERN and RIKEN, have intensively been used for materials research in in-beam and on-line Mössbauer experiments immediately after implantation of the nuclear probes.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Ion implantation in silicate glasses

    SciTech Connect

    Arnold, G.W.

    1993-12-01

    This review examines the effects of ion implantation on the physical properties of silicate glasses, the compositional modifications that can be brought about, and the use of metal implants to form colloidal nanosize particles for increasing the nonlinear refractive index.

  8. Ion implantation at elevated temperatures

    SciTech Connect

    Lam, N.Q.; Leaf, G.K.

    1985-11-01

    A kinetic model has been developed to investigate the synergistic effects of radiation-enhanced diffusion, radiation-induced segregation and preferential sputtering on the spatial redistribution of implanted solutes during implantation at elevated temperatures. Sample calculations were performed for Al and Si ions implanted into Ni. With the present model, the influence of various implantation parameters on the evolution of implant concentration profiles could be examined in detail.

  9. Metal Ion Sources for Ion Beam Implantation

    SciTech Connect

    Zhao, W. J.; Zhao, Z. Q.; Ren, X. T.

    2008-11-03

    In this paper a theme touched upon the progress of metal ion sources devoted to metal ion beam implantation (MIBI) will be reviewed. A special emphasis will be given to some kinds of ion sources such as ECR, MEVVA and Cluster ion sources. A novel dual hollow cathode metal ion source named DUHOCAMIS will be introduced and discussed.

  10. Ion beam processing of advanced electronic materials

    SciTech Connect

    Cheung, N.W.; Marwick, A.D.; Roberto, J.B.; International Business Machines Corp., Yorktown Heights, NY . Thomas J. Watson Research Center; Oak Ridge National Lab., TN )

    1989-01-01

    This report contains research programs discussed at the materials research society symposia on ion beam processing of advanced electronic materials. Major topics include: shallow implantation and solid-phase epitaxy; damage effects; focused ion beams; MeV implantation; high-dose implantation; implantation in III-V materials and multilayers; and implantation in electronic materials. Individual projects are processed separately for the data bases. (CBS)

  11. Tungsten contamination in ion implantation

    NASA Astrophysics Data System (ADS)

    Polignano, M. L.; Barbarossa, F.; Galbiati, A.; Magni, D.; Mica, I.

    2016-06-01

    In this paper the tungsten contamination in ion implantation processes is studied by DLTS analysis both in typical operating conditions and after contamination of the implanter by implantation of wafers with an exposed tungsten layer. Of course the contaminant concentration is orders of magnitude higher after contamination of the implanter, but in addition our data show that different mechanisms are active in a not contaminated and in a contaminated implanter. A moderate tungsten contamination is observed also in a not contaminated implanter, however in that case contamination is completely not energetic and can be effectively screened by a very thin oxide. On the contrary, the contamination due to an implantation in a previously contaminated implanter is reduced but not suppressed even by a relatively thick screen oxide. The comparison with SRIM calculations confirms that the observed deep penetration of the contaminant cannot be explained by a plain sputtering mechanism.

  12. Graphene synthesis by ion implantation

    NASA Astrophysics Data System (ADS)

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

    2010-11-01

    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.

  13. Graphene synthesis by ion implantation.

    PubMed

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

    2010-11-01

    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

  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)

    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.

  16. Ion implantation and laser annealing

    NASA Astrophysics Data System (ADS)

    Three ion implantation and laser annealing projects have been performed by ORNL through the DOE sponsored Seed Money Program. The research has contributed toward improving the characteristics of wear, hardness, and corrosion resistance of some metals and ceramics, as well as the electrical properties of semiconductors. The work has helped to spawn related research, at ORNL and elsewhere, concerning the relationships between microstructure and materials properties. ORNL research has resulted in major advances in extended life and non-corrosive artificial joints (hip and knee), high performance semiconductors, failure resistant ceramics (with potential energy applications), and solar cells. The success of the seed money projects was instrumental in the formation of ORNL's Surface Modification and Characterization Facility (SMAC). More than 60 universities and companies have participated in SMAC programs.

  17. Highly Stripped Ion Sources for MeV Ion Implantation

    SciTech Connect

    Hershcovitch, Ady

    2009-06-30

    charge state phosphorus and antimony could have resulted in a lower power consumption of 30 kW/implanter) 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. Nevertheless, BNL has benefited from advances in high-charge state ion generation, due to high charge state ions need for RHIC preinjection. 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. R&D of novel transport and gasless plasmaless deceleration, as well as decaborane molecular ion source to mitigate space charge problems in low energy shallow ion implantation was also conducted though results were not yet ready for commercialization. Future work should be focused on gasless plasmaless transport and deceleration as well as on molecular ions due to their significance to low energy, shallow implantation; which is the last frontier of ion implantation. To summarize the significant accomplishments: 1. Record steady state output currents of high charge state phosphorous, P, ions in particle milli-Ampere: P{sup 2+} (8.6 pmA), P{sup 3+} (1.9 pmA), and P{sup 4+} (0.12 pmA). 2. Record steady state output currents of high charge state antimony, Sb, ions in particle milli-Ampere: Sb{sup 3+} (16.2 pmA), Sb{sup 4+} (7.6 pmA), Sb{sup 5+} (3.3 pmA), and Sb{sup 6+} (2.2 pmA). 3. 70% output of boron ion current (compared to 25% in present state-of-the-art) from a Calutron-Bemas ion source. These accomplishments have the potential of benefiting the semiconductor

  18. 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.

  19. 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.

  20. Advances in lens implant technology

    PubMed Central

    Kampik, Anselm; Dexl, Alois K.; Zimmermann, Nicole; Glasser, Adrian; Baumeister, Martin; Kohnen, Thomas

    2013-01-01

    Cataract surgery is one of the oldest and the most frequent outpatient clinic operations in medicine performed worldwide. The clouded human crystalline lens is replaced by an artificial intraocular lens implanted into the capsular bag. During the last six decades, cataract surgery has undergone rapid development from a traumatic, manual surgical procedure with implantation of a simple lens to a minimally invasive intervention increasingly assisted by high technology and a broad variety of implants customized for each patient’s individual requirements. This review discusses the major advances in this field and focuses on the main challenge remaining – the treatment of presbyopia. The demand for correction of presbyopia is increasing, reflecting the global growth of the ageing population. Pearls and pitfalls of currently applied methods to correct presbyopia and different approaches under investigation, both in lens implant technology and in surgical technology, are discussed. PMID:23413369

  1. Advancing Binaural Cochlear Implant Technology

    PubMed Central

    McAlpine, David

    2015-01-01

    This special issue contains a collection of 13 papers highlighting the collaborative research and engineering project entitled Advancing Binaural Cochlear Implant Technology—ABCIT—as well as research spin-offs from the project. In this introductory editorial, a brief history of the project is provided, alongside an overview of the studies. PMID:26721929

  2. 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. PMID:26931931

  3. 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.

  4. Contamination Control in Ion Implantation

    SciTech Connect

    Eddy, R.; Doi, D.; Santos, I.; Wriggins, W.

    2011-01-07

    The investigation and elimination or control of metallic contamination in ion implanters has been a leading, continuous effort at implanter OEMs and in fabs/IDMs alike. Much of the efforts have been in the area of control of sputtering through material and geometry changes in apertures, beamline and target chamber components. In this paper, we will focus on an area that has not, heretofore, been fully investigated or controlled. This is the area of lubricants and internal and external support material such as selected cleaning media. Some of these materials are designated for internal use (beamline/vacuum) only while others are for internal and/or external use. Many applications for selected greases, for example, are designated for or are used for platens, implant disks/wheels and for wafer handling components. We will present data from popular lubricants (to be unnamed) used worldwide in ion implanters. This paper will review elements of concern in many lubricants that should be tracked and monitored by all fabs.Proper understanding of the characteristics, risks and the control of these potential contaminants can provide for rapid return to full process capability following major PMs or parts changes. Using VPD-ICPMS, Glow Discharge Mass Spectrometry and Ion Chromatography (IC) data, we will review the typical cleaning results and correlation to ''on wafer'' contamination by elements of concern--and by some elements that are otherwise barred from the fab.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. SEM analysis of ion implanted SiC

    NASA Astrophysics Data System (ADS)

    Malherbe, Johan B.; van der Berg, N. G.; Botha, A. J.; Friedland, E.; Hlatshwayo, T. T.; Kuhudzai, R. J.; Wendler, E.; Wesch, W.; Chakraborty, P.; da Silveira, E. F.

    2013-11-01

    SiC is a material used in two future energy production technologies, firstly as a photovoltaic layer to harness the UV spectrum in high efficient power solar cells, and secondly as a diffusion barrier material for radioactive fission products in the fuel elements of the next generation of nuclear power plants. For both applications, there is an interest in the implantation of reactive and non-reactive ions into SiC and their effects on the properties of the SiC. In this study 360 keV Ag+, I+ and Xe+ ions were separately implanted into 6H-SiC and in polycrystalline SiC at various substrate temperatures. The implanted samples were also annealed in vacuum at temperatures ranging from 900 °C to 1600 °C for various times. In recent years, there had been significant advances in scanning electron microscopy (SEM) with the introduction of an in-lens detector combined with field emission electron guns. This allows defects in solids, such as radiation damage created by the implanted ions, to be detected with SEM. Cross-sectional SEM images of 6H-SiC wafers implanted with 360 keV Ag+ ions at room temperature and at 600 °C and then vacuum annealed at different temperatures revealed the implanted layers and their thicknesses. A similar result is shown of 360 keV I+ ions implanted at 600 °C into 6H-SiC and annealed at 1600 °C. The 6H-SiC is not amorphized but remained crystalline when implanting at 600 °C. There are differences in the microstructure of 6H-SiC implanted with silver at the two temperatures as well as with reactive iodine ions. Voids (bubbles) are created in the implanted layers into which the precipitation of silver and iodine can occur after annealing of the samples. The crystallinity of the substrate via implantation temperature caused differences in the distribution and size of the voids. Implantation of xenon ions in polycrystalline SiC at 350 °C does not amorphize the substrate as is the case with room temperature heavy ion bombardment. Subsequent

  11. Ion implantation into concave polymer surface

    NASA Astrophysics Data System (ADS)

    Sakudo, N.; Shinohara, T.; Amaya, S.; Endo, H.; Okuji, S.; Ikenaga, N.

    2006-01-01

    A new technique for ion implantation into concave surface of insulating materials is proposed and experimentally studied. The principle is roughly described by referring to modifying inner surface of a PET (polyethylene terephthalate) bottle. An electrode that is supplied with positive high-voltage pulses is inserted into the bottle. Both plasma formation and ion implantation are simultaneously realized by the same high-voltage pulses. Ion sheath with a certain thickness that depends on plasma parameters is formed just on the inner surface of the bottle. Since the plasma potential is very close to that of the electrode, ions from the plasma are accelerated in the sheath and implanted perpendicularly into the bottle's inner surface. Laser Raman spectroscopy shows that the inner surface of an ion-implanted PET bottle is modified into DLC (diamond-like carbon). Gas permeation measurement shows that gas-barrier property enhances due to the modification.

  12. Versatile high current metal ion implantation facility

    SciTech Connect

    Brown, I.G.; Dickinson, M.R.; Galvin, J.E.; Godechot, X.; MacGill, R.A.

    1991-06-01

    A metal ion implantation facility has been developed with which high current beams of practically all the solid metals of the periodic table can be produced. A multi-cathode, broad beam, metal vapor vacuum arc ion source is used to produce repetitively pulsed metal ion beams at an extraction voltage of up to 100 kV, corresponding to an ion energy of up to several hundred keV because of the ion-charge state multiplicity, and with a beam current of up to several amperes peak pulsed and several tens of mA time averaged delivered onto a downstream target. Implantation is done in a broad-beam mode, with a direct line-of-sight from ion source to target. Here we summarize some of the features of the ion source and the implantation facility that has been built up around it. 28 refs., 5 figs.

  13. Ion Implantation with Scanning Probe Alignment

    SciTech Connect

    Persaud, A.; Liddle, J.A.; Schenkel, T.; Bokor, J.; Ivanov, Tzv.; Rangelow, I.W.

    2005-07-12

    We describe a scanning probe instrument which integrates ion beams with the imaging and alignment function of a piezo-resistive scanning probe in high vacuum. The beam passes through several apertures and is finally collimated by a hole in the cantilever of the scanning probe. The ion beam spot size is limited by the size of the last aperture. Highly charged ions are used to show hits of single ions in resist, and we discuss the issues for implantation of single ions.

  14. Ion-implantation doping of silicon carbide

    SciTech Connect

    Gardner, J.; Edwards, A.; Rao, M.V.; Papanicolaou, N.; Kelner, G.; Holland, O.W.

    1997-10-01

    Because of their commercial availability in bulk single crystal form, the 6H- and 4H- polytypes of SiC are gaining importance for high-power, high-temperature, and high-frequency device applications. Selective area doping is a crucial processing step in integrated circuit manufacturing. In Si technology, selective area doping is accomplished by thermal diffusion or ion-implantation. Because of the low diffusion coefficients of most impurities in SiC, ion implantation is indispensable in SiC device manufacturing. In this paper the authors present their results on donor, acceptor, and compensation implants in 6H-SiC.

  15. Computerized implant-dentistry: Advances toward automation

    PubMed Central

    Gulati, Minkle; Anand, Vishal; Salaria, Sanjeev Kumar; Jain, Nikil; Gupta, Shilpi

    2015-01-01

    Advancements in the field of implantology such as three-dimensional imaging, implant-planning software, computer-aided-design/computer-aided-manufacturing (CAD/CAM) technology, computer-guided, and navigated implant surgery have led to the computerization of implant-dentistry. This three-dimensional computer-generated implant-planning and surgery has not only enabled accurate preoperative evaluation of the anatomic limitations but has also facilitated preoperative planning of implant positions along with virtual implant placement and subsequently transferring the virtual treatment plans onto the surgical phase via static (guided) or dynamic (navigated) systems aided by CAD/CAM technology. Computerized-implant-dentistry being highly predictable and minimally invasive in nature has also allowed implant placement in patients with medical comorbidities (e.g. radiation therapy, blood dyscrasias), in patients with complex problems following a significant alteration of the bony anatomy as a result of benign or malignant pathology of the jaws or trauma and in patients with other physical and emotional problems. With significant achievements accomplished in the field of computerized implant-dentistry, attempts are now been made toward complete automation of implant-dentistry. PMID:25810585

  16. Key issues in plasma source ion implantation

    SciTech Connect

    Rej, D.J.; Faehl, R.J.; Matossian, J.N.

    1996-09-01

    Plasma source ion implantation (PSII) is a scaleable, non-line-of-sight method for the surface modification of materials. In this paper, we consider three important issues that should be addressed before wide-scale commercialization of PSII: (1) implant conformality; (2) ion sources; and (3) secondary electron emission. To insure uniform implanted dose over complex shapes, the ion sheath thickness must be kept sufficiently small. This criterion places demands on ion sources and pulsed-power supplies. Another limitation to date is the availability of additional ion species beyond B, C, N, and 0. Possible solutions are the use of metal arc vaporization sources and plasma discharges in high-vapor-pressure organometallic precursors. Finally, secondary electron emission presents a potential efficiency and x-ray hazard issue since for many metallurgic applications, the emission coefficient can be as large as 20. Techniques to suppress secondary electron emission are discussed.

  17. Advanced process control and novel test methods for PVD silicon and elastomeric silicone coatings utilized on ion implant disks, heatsinks and selected platens

    SciTech Connect

    Springer, J.; Allen, B.; Wriggins, W.; Kuzbyt, R.; Sinclair, R.

    2012-11-06

    Coatings play multiple key roles in the proper functioning of mature and current ion implanters. Batch and serial implanters require strategic control of elemental and particulate contamination which often includes scrutiny of the silicon surface coatings encountering direct beam contact. Elastomeric Silicone Coatings must accommodate wafer loading and unloading as well as direct backside contact during implant plus must maintain rigid elemental and particulate specifications. The semiconductor industry has had a significant and continuous effort to obtain ultra-pure silicon coatings with sustained process performance and long life. Low particles and reduced elemental levels for silicon coatings are a major requirement for process engineers, OEM manufacturers, and second source suppliers. Relevant data will be presented. Some emphasis and detail will be placed on the structure and characteristics of a relatively new PVD Silicon Coating process that is very dense and homogeneous. Wear rate under typical ion beam test conditions will be discussed. The PVD Silicon Coating that will be presented here is used on disk shields, wafer handling fingers/fences, exclusion zones of heat sinks, beam dumps and other beamline components. Older, legacy implanters can now provide extended process capability using this new generation PVD silicon - even on implanter systems that were shipped long before the advent of silicon coating for contamination control. Low particles and reduced elemental levels are critical performance criteria for the silicone elastomers used on disk heatsinks and serial implanter platens. Novel evaluation techniques and custom engineered tools are used to investigate the surface interaction characteristics of multiple Elastomeric Silicone Coatings currently in use by the industry - specifically, friction and perpendicular stiction. These parameters are presented as methods to investigate the critical wafer load and unload function. Unique tools and test

  18. Advanced process control and novel test methods for PVD silicon and elastomeric silicone coatings utilized on ion implant disks, heatsinks and selected platens

    NASA Astrophysics Data System (ADS)

    Springer, J.; Allen, B.; Wriggins, W.; Kuzbyt, R.; Sinclair, R.

    2012-11-01

    Coatings play multiple key roles in the proper functioning of mature and current ion implanters. Batch and serial implanters require strategic control of elemental and particulate contamination which often includes scrutiny of the silicon surface coatings encountering direct beam contact. Elastomeric Silicone Coatings must accommodate wafer loading and unloading as well as direct backside contact during implant plus must maintain rigid elemental and particulate specifications. The semiconductor industry has had a significant and continuous effort to obtain ultra-pure silicon coatings with sustained process performance and long life. Low particles and reduced elemental levels for silicon coatings are a major requirement for process engineers, OEM manufacturers, and second source suppliers. Relevant data will be presented. Some emphasis and detail will be placed on the structure and characteristics of a relatively new PVD Silicon Coating process that is very dense and homogeneous. Wear rate under typical ion beam test conditions will be discussed. The PVD Silicon Coating that will be presented here is used on disk shields, wafer handling fingers/fences, exclusion zones of heat sinks, beam dumps and other beamline components. Older, legacy implanters can now provide extended process capability using this new generation PVD silicon - even on implanter systems that were shipped long before the advent of silicon coating for contamination control. Low particles and reduced elemental levels are critical performance criteria for the silicone elastomers used on disk heatsinks and serial implanter platens. Novel evaluation techniques and custom engineered tools are used to investigate the surface interaction characteristics of multiple Elastomeric Silicone Coatings currently in use by the industry - specifically, friction and perpendicular stiction. These parameters are presented as methods to investigate the critical wafer load and unload function. Unique tools and test

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

    NASA Astrophysics Data System (ADS)

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

    2009-05-01

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

  20. 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.

  1. Investigation on plasma immersion ion implantation treated medical implants.

    PubMed

    Mändl, S; Sader, R; Thorwarth, G; Krause, D; Zeilhofer, H-F; Horch, H H; Rauschenbach, B

    2002-08-01

    In this work the biocompatibility of osteosynsthesis plates treated with plasma immersion ion implantation (PIII) was tested using a rat model. Small rods (Ø 0.9 mm, and length 10 mm) prepared from different materials-pure Ti, anodised Ti, and two NiTi alloys (SE 508, and SM 495)-were implanted with oxygen by PIII to form a rutile surface layer and subsequently inserted into rat femurs, together with a control group of untreated samples. The results of the biomechanical tests correlate with the histological results, and show that plasma immersion ion implantation leads to an increase of biocompatibility and osseointegration of titanium and NiTi, albeit no improvement of the (bad) biocompatibility of the anodised Ti. Despite the layer thickness of up to 0.5 microm a strong influence of the base material is still present. PMID:12202173

  2. Evolution of defects in silicon carbide implanted with helium ions

    NASA Astrophysics Data System (ADS)

    Zhang, Chonghong; Song, Yin; Yang, Yitao; Zhou, Chunlan; Wei, Long; Ma, Hongji

    2014-05-01

    Effects of accumulation of radiation damage in silicon carbide are important concerns for the use of silicon carbide in advanced nuclear energy systems. In the present work lattice damage in silicon carbide crystal (4H type) implanted with 100 keV 4He+ ions was investigated with Rutherford backscattering spectrometry in channeling geometry (RBS/c) and positron beam Doppler broadening spectrometry (PBDB). Helium implantation was performed at the specimen temperature of 510 K to avoid amorphization of the SiC crystal. Fluences of helium ions were selected to be in the range from 1 × 1016 to 3 × 1016 ions cm-2, around the dose threshold for the formation of observable helium bubbles under transmission electron microscopes (TEM). The RBS/c measurements show distinctly different annealing behavior of displaced Si atoms at doses below or above the threshold for helium bubble formation. The RBS/c yield in the peak damage region of the specimen implanted to 3 × 1016 He-ions cm-2 shows an increase on the subsequently thermal annealing above 873 K, which is readily ascribed to the extra displacement of Si atoms due to helium bubble growth. The RBS/c yield in the specimen implanted to a lower ion fluence of 1.5 × 1016 He-ions cm-2 decreases monotonously on annealing from ambient temperatures up to 1273 K. The PBDB measurements supply evidence of clustering of vacancies at temperatures from 510 to 1173 K, and dissociation of vacancy clusters above 1273 K. The similarity of annealing behavior in PBDB profiles for helium implantation to 1 × 1016 and 3 × 1016 ions cm-2 is ascribed to the saturation of trapping of positrons in vacancy type defects in the damaged layers in the specimens helium-implanted to the two dose levels.

  3. Annealing of ion implanted gallium nitride

    SciTech Connect

    Tan, H.H.; Williams, J.S.; Zou, J.; Cockayne, D.J.; Pearton, S.J.; Zolper, J.C.; Stall, R.A.

    1998-03-01

    In this paper, we examine Si and Te ion implant damage removal in GaN as a function of implantation dose, and implantation and annealing temperature. Transmission electron microscopy shows that amorphous layers, which can result from high-dose implantation, recrystallize between 800 and 1100{degree}C to very defective polycrystalline material. Lower-dose implants (down to 5{times}10{sup 13}cm{sup {minus}2}), which are not amorphous but defective after implantation, also anneal poorly up to 1100{degree}C, leaving a coarse network of extended defects. Despite such disorder, a high fraction of Te is found to be substitutional in GaN both following implantation and after annealing. Furthermore, although elevated-temperature implants result in less disorder after implantation, this damage is also impossible to anneal out completely by 1100{degree}C. The implications of this study are that considerably higher annealing temperatures will be needed to remove damage for optimum electrical properties. {copyright} {ital 1998 American Institute of Physics.}

  4. 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.

  5. 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. PMID:26932065

  6. 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.

  7. 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.

  8. Plasma immersion ion implantation for silicon processing

    NASA Astrophysics Data System (ADS)

    Yankov, Rossen A.; Mändl, Stephan

    2001-04-01

    Plasma Immersion Ion Implantation (PIII) is a technology which is currently widely investigated as an alternative to conventional beam line implantation for ultrashallow doping beyond the 0.15 m technology. However, there are several other application areas in modern semiconductor processing. In this paper a detailed discussion of the PIII process for semiconductors and of actual as well as future applications is given. Besides the well known advantages of PIII - fast process, implantation of the whole surface, low cost of ownership - several peculiarities - like spread of the implantation energy due to finite rise time or collisions, no mass separation, high secondary electron emission - must be mentioned. However, they can be overcome by adjusting the system and the process parameters. Considering the applications, ultrashallow junction formation by PIII is an established industrial process, whereas SIMOX and Smart-Cut by oxygen and hydrogen implantation are current topics between research and introduction into industry. Further applications of PIII, of which some already are research topics and some are only investigated by conventional ion implantation, include seeding for metal deposition, gettering of metal impurities, etch stop layers and helium implantation for localized lifetime control.

  9. Ion-implantation damage in silicate glasses

    NASA Astrophysics Data System (ADS)

    Arnold, G. W.

    Ion implantation is a rapid technique for simulating damage induced by alpha recoil nuclei in nuclear waste forms. The simulation has been found to be quite good in TEM comparisons with natural alpha decay damage in minerals, but leach rate differences have been observed in glass studies and were attributed to dose rate differences. The similarities between ion implantation and recoil nuclei as a means of producing damage suggest that insights into the long term behavior of glass waste forms can be obtained by examination of what is known about ion implantation damage in silicate glasses. This paper briefly reviews these effects and shows that leaching results in certain nuclear waste glasses can be understood as resulting from plastic flow and track overlap. Phase separation is also seen to be a possible consequence of damage induced compositional changes.

  10. 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.

  11. Recent advances in vacuum arc ion sources

    SciTech Connect

    Brown, I.G.; Anders, A.; Anders, S.; Dickinson, M.R.; MacGill, R.A.; Oks, E.M.

    1995-07-01

    Intense beams of metal ions can be formed from a vacuum arc ion source. Broadbeam extraction is convenient, and the time-averaged ion beam current delivered downstream can readily be in the tens of milliamperes range. The vacuum arc ion source has for these reasons found good application for metallurgical surface modification--it provides relatively simple and inexpensive access to high dose metal ion implantation. Several important source developments have been demonstrated recently, including very broad beam operation, macroparticle removal, charge state enhancement, and formation of gaseous beams. The authors have made a very broad beam source embodiment with beam formation electrodes 50 cm in diameter, producing a beam of width {approximately}35 cm for a nominal beam area of {approximately}1,000 cm{sup 2}, and a pulsed Ti beam current of about 7 A was formed at a mean ion energy of {approximately}100 keV. Separately, they`ve developed high efficiency macroparticle-removing magnetic filters and incorporated such a filter into a vacuum arc ion source so as to form macroparticle-free ion beams. Jointly with researchers at the High Current Electronics Institute at Tomsk, Russia, and the Gesellschaft fuer Schwerionenforschung at Darmstadt, Germany, they`ve developed a compact technique for increasing the charge states of ions produced in the vacuum arc plasma and thus providing a simple means of increasing the ion energy at fixed extractor voltage. Finally, operation with mixed metal and gaseous ion species has been demonstrated. Here, they briefly review the operation of vacuum marc ion sources and the typical beam and implantation parameters that can be obtained, and describe these source advances and their bearing on metal ion implantation applications.

  12. High energy implantation with high-charge-state ions in a vacuum arc ion implanter

    SciTech Connect

    Oks, E.M. |; Anders, A.; Brown, I.G.; Dickinson, M.R.; MacGill, R.A.

    1996-08-01

    Ion implantation energy can in principal be increased by increasing the charge states of the ions produced by the ion source rather than by increasing the implanter operating voltage, providing an important savings in cost and size of the implanter. In some recent work the authors have shown that the charge states of metal ions produced in a vacuum arc ion source can be elevated by a strong magnetic field. In general, the effect of both high arc current and high magnetic field is to push the distribution to higher charge states--the mean ion charge state is increased and new high charge states are formed. The effect is significant for implantation application--the mean ion energy can be about doubled without change in extraction voltage. Here they describe the ion source modifications, the results of time-of-flight measurements of ion charge state distributions, and discuss the use and implications of this technique as a means for doing metal iron implantation in the multi-hundreds of keV ion energy range.

  13. Ion implantation and annealing studies in III-V nitrides

    SciTech Connect

    Zolper, J.C.; Pearton, S.J.; Williams, J.S.; Tan, H.H.; Karlicek, R.J. Jr.; Stall, R.A.

    1996-12-31

    Ion implantation doping and isolation is expected to play an enabling role for the realization of advanced III-Nitride based devices. In fact, implantation has already been used to demonstrate n- and p-type doping of GaN with Si and Mg or Ca, respectively, as well as to fabricate the first GaN junction field effect transistor. Although these initial implantation studies demonstrated the feasibility of this technique for the III-Nitride materials, further work is needed to realize its full potential. After reviewing some of the initial studies in this field, the authors present new results for improved annealing sequences and defect studies in GaN. First, sputtered AlN is shown by electrical characterization of Schottky and Ohmic contacts to be an effect encapsulant of GaN during the 1,100 C implant activation anneal. The AlN suppresses N-loss from the GaN surface and the formation of a degenerate n{sup +}-surface region that would prohibit Schottky barrier formation after the implant activation anneal. Second, they examine the nature of the defect generation and annealing sequence following implantation using both Rutherford Backscattering (RBS) and Hall characterization. They show that for a Si-dose of 1 x 10{sup 16} cm{sup {minus}2} 50% electrical donor activation is achieved despite a significant amount of residual implantation-induced damage in the material.

  14. 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.

  15. 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.

  16. 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.

  17. III-Nitride ion implantation and device processing

    SciTech Connect

    Zolper, J.C.; Shul, R.J.; Baca, A.G.; Pearton, S.J.; Abernathy, C.R.; Wilson, R.G.; Stall, R.A.; Shur, M.

    1996-06-01

    Ion implantation doping and isolation has played a critical role in realizing high performance photonic and electronic devices in all mature semiconductor materials; this is also expected for binary III-Nitride materials (InN, GaN, AlN) and their alloys as epitaxy improves and more advanced device structures fabricated. This paper reports on recent progress in ion implantation doping of III-Nitride materials that has led to the first demonstration of a GaN JFET (junction field effect transistor). The JFET was fabricated with all ion implantation doping; in particular, p-type doping of GaN with Ca has been demonstrated with an estimated acceptor ionization energy of 169 meV. O-implantation has also been studied and shown to yield n-type conduction with an ionization energy of {similar_to}29 meV. Neither Ca or O display measurable redistribution during a 1125 C, 15 s activation anneal which sets an upper limit on their diffusivity at this temperature of 2.7{times}10{sup {minus}13}cm{sup 2}/s.

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

    PubMed

    Luo, J; Li, L H; Liu, H T; Yu, K M; Xu, Y; Zuo, X J; Zhu, P Z; Ma, Y F; Fu, Ricky K Y; Chu, Paul K

    2014-06-01

    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. PMID:24985818

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

    NASA Astrophysics Data System (ADS)

    Luo, J.; Li, L. H.; Liu, H. T.; Yu, K. M.; Xu, Y.; Zuo, X. J.; Zhu, P. Z.; Ma, Y. F.; Fu, Ricky K. Y.; Chu, Paul K.

    2014-06-01

    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.

  1. 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.

  2. 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.

  3. 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

  4. Surface mechanical properties - effects of ion implantation

    NASA Astrophysics Data System (ADS)

    Herman, Herbert

    1981-05-01

    Ion implantation has been used to modify the mechanical properties of a wide range of metals and alloys. The affected properties which have been studied include friction and wear, erosion and fatigue. Both BCC and FCC systems have been examined, with the major effort being directed at the former, due to the strong influence of interstitial implantants on mechanical properties of BCC and because of the industrial utility of these alloys. In seeking the microstructural origins of these sometimes dramatic effects, researchers have employed numerous surface analysis techniques, including backscattering and electron spectroscopy, TEM, SEM, X-ray and Mössbauer analysis and internal friction measurements. The interactions of surface dislocation structures with implantation-induced imperfections, surface alloying, and precipitation phenomena are discussed. A review is given of the current status of activities as represented by a number of research groups.

  5. 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. PMID:27482462

  6. 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

  7. 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.

  8. 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.

  9. Electrocatalysis on ion-implanted electrodes

    SciTech Connect

    O'Grady, W E; Wolf, G K

    1981-01-01

    The oxidation of formic acid and methanol has been stuidied on electrodes prepared by ion implanting Pt in RuO/sup 2/. Formic acid was found to oxidize readily on this catalyst without poisoning the surface. In the case of methanol no reaction was found to take place. Using XPS techniques, Pt was shown to have a lower binding energy than bulk Pt. This suggests that there is excess charge on this form of Pt which changes its reactivity.

  10. Molecular Ion Beam Transportation for Low Energy Ion Implantation

    SciTech Connect

    Kulevoy, T. V.; Kropachev, G. N.; Seleznev, D. N.; Yakushin, P. E.; Kuibeda, R. P.; Kozlov, A. V.; Koshelev, V. A.; Hershcovitch, A.; Johnson, B. M.; Gushenets, V. I.; Oks, E. M.; Polozov, S. M.; Poole, H. J.

    2011-01-07

    A joint research and development of steady state intense boron ion sources for 100's of electron-volt ion implanters has been in progress for the past five years. Current density limitation associated with extracting and transporting low energy ion beams result in lower beam currents that in turn adversely affects the process throughput. The transport channel with electrostatic lenses for decaborane (B{sub 10}H{sub 14}) and carborane (C{sub 2}B{sub 10}H{sub 12}) ion beams transportation was developed and investigated. The significant increase of ion beam intensity at the beam transport channel output is demonstrated. The transport channel simulation, construction and experimental results of ion beam transportation are presented.

  11. Development of a microwave ion source for ion implantations.

    PubMed

    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. PMID:26932118

  12. 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.

  13. Advances in implantable cardioverter defibrillator therapy.

    PubMed

    Rickard, John; Wilkoff, Bruce L

    2016-03-01

    Since the first implant in 1980, implantable cardioverter defibrillator (ICD) technology has progressed rapidly. Modern ICD's have hundreds of programmable options with the general goal of preventing inappropriate shocks and providing shocks for truly life threatening symptomatic ventricular arrhythmias. New studies on ICD programming have shown the benefits of prolonged detection intervals in reaching this goal. Anti-tachycardia pacing (ATP) therapy has become an important adjunct to defibrillator shocks. Remote monitoring technologies have surfaced which have been shown to identify arrhythmias and problems with the device in an expedient fashion. The subcutaneous ICD offers the advantage of avoiding intravascular leads and their inherent risks. Lastly, the current understanding of the effects of MRI in ICD patients has advanced creating new opportunities to provide MRI safely to such patients. PMID:26653411

  14. 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.

  15. Evolution of Ion Implantation Technology and its Contribution to Semiconductor Industry

    SciTech Connect

    Tsukamoto, Katsuhiro; Kuroi, Takashi; Kawasaki, Yoji

    2011-01-07

    Industrial aspects of the evolution of ion implantation technology will be reviewed, and their impact on the semiconductor industry will be discussed. The main topics will be the technology's application to the most advanced, ultra scaled CMOS, and to power devices, as well as productivity improvements in implantation technology. Technological insights into future developments in ion-related technologies for emerging industries will also be presented.

  16. Simulation of ion beam transport through the 400 Kv ion implanter at Michigan Ion Beam Laboratory

    SciTech Connect

    Naab, F. U.; Toader, O. F.; Was, G. S.

    2013-04-19

    The Michigan Ion Beam Laboratory houses a 400 kV ion implanter. An application that simulates the ion beam trajectories through the implanter from the ion source to the target was developed using the SIMION Registered-Sign code. The goals were to have a tool to develop an intuitive understanding of abstract physics phenomena and diagnose ion trajectories. Using this application, new implanter users of different fields in science quickly understand how the machine works and quickly learn to operate it. In this article we describe the implanter simulation application and compare the parameters of the implanter components obtained from the simulations with the measured ones. The overall agreement between the simulated and measured values of magnetic fields and electric potentials is {approx}10%.

  17. 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.

  18. 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.

  19. Mutagenesis of Arabidopsis Thaliana by N+ Ion Implantation

    NASA Astrophysics Data System (ADS)

    Zhang, Genfa; Shi, Xiaoming; Nie, Yanli; Jiang, Shan; Zhou, Hongyu; Lu, Ting; Zhang, Jun

    2006-05-01

    Ion implantation, as a new biophysically mutagenic technique, has shown a great potential for crop breeding. By analyzing polymorphisms of genomic DNA through RAPD-based DNA analysis, we compared the frequency and efficiency of somatic and germ-line mutations of Arabidopsis thaliana treated with N+ ion implantation and γ-rays radiation. Our data support the following conclusions: (1) N+ ion implantation can induce a much wider spectrum of mutations than γ-rays radiation does; (2) Unlike the linear correlation between the doses and their effect in γ-rays radiation, the dose-effect correlation in N+ ion implantation is nonlinear; (3) Like γ-rays radiation, both somatic and germ-line mutations could be induced by N+ ion implantation; and (4) RAPD deletion patterns are usually seen in N+ ion implantation induced mutation.

  20. 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.

  1. 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.

  2. Flame annealing of ion implanted silicon

    SciTech Connect

    Narayan, J.; Young, R.T.

    1983-01-01

    The authors investigated flame annealing of ion implantation damage (consisting of amorphous layers and dislocation loops) in (100) and (111) silicon substrates. The temperature of a hydrogen flame was varied from 1050 to 1200/sup 0/C and the interaction time from 5 to 10 seconds. Detailed TEM results showed that a defect-free annealing of amorphous layers by solid-phase-epitaxial growth could be achieved up to a certain concentration. However, dislocation loops in the region below the amorphous layer exhibited coarsening, i.e., the average loop size increased while the number density of loops decreased. Above a critical loop density, which was found to be a function of ion implantation variables and substrate temperature, formation of 90/sup 0/ dislocations (a cross-grid of dislocation in (100) and a triangular grid in (111) specimens) were observed. Electrical (Van der Pauw) measurements indicated nearly a complete electrical activation of dopants with mobility comparable to pulsed laser annealed specimens. The characteristics of p-n junction diodes showed a good diode perfection factor of 1.20-1.25 and low reverse bias currents.

  3. 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.

  4. Advanced ion thruster research

    NASA Technical Reports Server (NTRS)

    Wilbur, P. J.

    1985-01-01

    A series of experiments conducted on a ring cusp magnetic field ion thruster; in which the anode, cathode and discharge chamber backplate were moved relative to the magnetic cusp; are described. Optimum locations for the anode, cathode and backplate which yield the lowest energy cost per plasma ion and highest extracted ion fraction are identified. The results are discussed in terms of simple physical models. The results of preliminary experiments into the operation of hollow cathodes on nitrogen and xenon over a large pressure range (0.1 to 100 Torr) are presented. They show that the cathode discharge transfers from the cathode insert to the exterior edge of the orifice plate as the interelectrode pressure is increased. Experimental evidence showing that a new ion extractor grid concept can be used to stabilize the plasma sheath at the screen grid is presented. This concept, identified by the term constrained sheath optics, is shown to hold ion beamlet divergence and impingement characteristics to stable values as the beamlet current and the net and total accelerating voltages are changed. The current status of a study of beamlet vectoring induced by displacing the accelerator and/or decelerator grids of a three grid ion extraction system relative to the screen grid is discussed.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Ion implantation induced blistering of rutile single crystals

    NASA Astrophysics Data System (ADS)

    Xiang, Bing-Xi; Jiao, Yang; Guan, Jing; Wang, Lei

    2015-07-01

    The rutile single crystals were implanted by 200 keV He+ ions with a series fluence and annealed at different temperatures to investigate the blistering behavior. The Rutherford backscattering spectrometry, optical microscope and X-ray diffraction were employed to characterize the implantation induced lattice damage and blistering. It was found that the blistering on rutile surface region can be realized by He+ ion implantation with appropriate fluence and the following thermal annealing.

  12. Advanced ion thruster research

    NASA Technical Reports Server (NTRS)

    Wilbur, P. J.

    1984-01-01

    A simple model describing the discharge chamber performance of high strength, cusped magnetic field ion thrusters is developed. The model is formulated in terms of the energy cost of producing ions in the discharge chamber and the fraction of ions produced in the discharge chamber that are extracted to form the ion beam. The accuracy of the model is verified experimentally in a series of tests wherein the discharge voltage, propellant, grid transparency to neutral atoms, beam diameter and discharge chamber wall temperature are varied. The model is exercised to demonstrate what variations in performance might be expected by varying discharge chamber parameters. The results of a study of xenon and argon orificed hollow cathodes are reported. These results suggest that a hollow cathode model developed from research conducted on mercury cathodes can also be applied to xenon and argon. Primary electron mean free paths observed in argon and xenon cathodes that are larger than those found in mercury cathodes are identified as a cause of performance differences between mercury and inert gas cathodes. Data required as inputs to the inert gas cathode model are presented so it can be used as an aid in cathode design.

  13. 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. PMID:24632388

  14. In-situ deposition of sacrificial layers during ion implantation

    SciTech Connect

    Anders, A.; Anders, S.; Brown, I.G.; Yu, K.M.

    1995-02-01

    The retained dose of implanted ions is limited by sputtering. It is known that a sacrificial layer deposited prior to ion implantation can lead to an enhanced retained dose. However, a higher ion energy is required to obtain a similar implantation depth due to the stopping of ions in the sacrificial layer. It is desirable to have a sacrificial layer of only a few monolayers thickness which can be renewed after it has been sputtered away. We explain the concept and describe two examples: (i) metal ion implantation using simultaneously a vacuum arc ion source and filtered vacuum arc plasma sources, and (ii) Metal Plasma Immersion Ion Implantation and Deposition (MePIIID). In MePIIID, the target is immersed in a metal or carbon plasma and a negative, repetitively pulsed bias voltage is applied. Ions are implanted when the bias is applied while the sacrificial layer suffers sputtering. Low-energy thin film deposition - repair of the sacrificial layer -- occurs between bias pulses. No foreign atoms are incorporated into the target since the sacrificial film is made of the same ion species as used in the implantation phase.

  15. A commercial plasma source ion implantation facility

    SciTech Connect

    Scheuer, J.T.; Adler, R.A.; Horne, W.G.

    1996-10-01

    Empire Hard Chrome has recently installed commercial plasma source ion implantation (PSU) equipment built by North Star Research Corporation. Los Alamos National Laboratory has assisted in this commercialization effort via two Cooperative Research and Development Agreements to develop the plasma source for the equipment and to identify low-risk commercial PSII applications. The PSII system consists of a 1 m x 1 m cylindrical vacuum chamber with a rf plasma source. The pulse modulator is capable of delivering pulses kV and peak currents of 300 A at maximum repetition rate of 400 Hz. thyratron tube to switch a pulse forming network which is tailored to match the dynamic PSII load. In this paper we discuss the PSII system, process facility, and early commercial applications to production tooling.

  16. Modification of sol-gel coatings by ion implantation

    NASA Astrophysics Data System (ADS)

    Hirashima, Hiroshi; Adachi, Kenji; Imai, Hiroaki

    1994-10-01

    In order to densify and to improve the physical properties, TiO2 sol-gel films, about 100 nm in thickness, on silica glass or silicon wafer were implanted with Ar+ or B+ ions. The refractive index of the as-dried films increased and the IR absorption band of OH disappeared after Ar+ implantation. Dehydration and densification of sol-gel films were enhanced by Ar+ implantation. On the other hand, the refractive index and the thickness of the films hardly changed by B+ implantation. However, IR absorption bands attributed to B-O bond were observed after B+ implantation. This suggests that sol-gel films could be chemically modified by ion implantation with reactive ion species.

  17. 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.

  18. Ion Implantation into Presolar Grains: A Theoretical Model

    NASA Astrophysics Data System (ADS)

    Verchovsky, A. B.; Wright, I. P.; Pillinger, C. T.

    A numerical model for ion implantation into spherical grains in free space has been developed. It can be applied to single grains or collections of grains with known grain-size distributions. Ion-scattering effects were taken into account using results of computer simulations. Possible isotope and element fractionation of the implanted species was investigated using this model. The astrophysical significance of the model lies in the possible identification of energetically different components (such as noble gases) implanted into presolar grains (such as diamond and SiC) and in establishing implantation energies of the components.

  19. Microstructure evolution in carbon-ion implanted sapphire

    SciTech Connect

    Orwa, J. O.; McCallum, J. C.; Jamieson, D. N.; Prawer, S.; Peng, J. L.; Rubanov, S.

    2010-01-15

    Carbon ions of MeV energy were implanted into sapphire to fluences of 1x10{sup 17} or 2x10{sup 17} cm{sup -2} and thermally annealed in forming gas (4% H in Ar) for 1 h. Secondary ion mass spectroscopy results obtained from the lower dose implant showed retention of implanted carbon and accumulation of H near the end of range in the C implanted and annealed sample. Three distinct regions were identified by transmission electron microscopy of the implanted region in the higher dose implant. First, in the near surface region, was a low damage region (L{sub 1}) composed of crystalline sapphire and a high density of plateletlike defects. Underneath this was a thin, highly damaged and amorphized region (L{sub 2}) near the end of range in which a mixture of i-carbon and nanodiamond phases are present. Finally, there was a pristine, undamaged sapphire region (L{sub 3}) beyond the end of range. In the annealed sample some evidence of the presence of diamond nanoclusters was found deep within the implanted layer near the projected range of the C ions. These results are compared with our previous work on carbon implanted quartz in which nanodiamond phases were formed only a few tens of nanometers from the surface, a considerable distance from the projected range of the ions, suggesting that significant out diffusion of the implanted carbon had occurred.

  20. 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%.

  1. Ion implantation processing of GaN epitaxial layers

    SciTech Connect

    Tan, H.H.; Williams, J.S.; Zou, J.; Cockayne, D.J.H.; Pearton, S.J.; Yuan, C.

    1996-12-31

    Ion implantation induced-damage build up in epitaxial GaN layers grown on sapphire has been analyzed by ion channeling and electron microscopy techniques. The epitaxial layers are extremely resistant to ion beam damage in that substantial dynamic annealing of implantation disorder occurs even at liquid nitrogen temperatures. Amorphous layers can be formed in some cases if the implantation dose is high enough. However, the damage (amorphous or complex extended defects) that is formed is also extremely difficult to remove during annealing and required temperatures in excess of 1,100 C.

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

    DOEpatents

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

    1991-01-01

    A Planar-Buried-Heterostructure, Graded-Index, Separate-Confinement-Heterostructure semiconductor diode laser 10 includes a single quantum well or multi-quantum well active stripe 12 disposed between a p-type compositionally graded Group III-V cladding layer 14 and an n-type compositionally graded Group III-V cladding layer 16. The laser 10 includes an ion implanted n-type region 28 within the p-type cladding layer 14 and further includes an ion implanted p-type region 26 within the n-type cladding layer 16. The ion implanted regions are disposed for defining a lateral extent of the active stripe.

  3. 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.

  4. Modification of medical metals by ion implantation of copper

    NASA Astrophysics Data System (ADS)

    Wan, Y. Z.; Xiong, G. Y.; Liang, H.; Raman, S.; He, F.; Huang, Y.

    2007-10-01

    The effect of copper ion implantation on the antibacterial activity, wear performance and corrosion resistance of medical metals including 317 L of stainless steels, pure titanium, and Ti-Al-Nb alloy was studied in this work. The specimens were implanted with copper ions using a MEVVA source ion implanter with ion doses ranging from 0.5 × 10 17 to 4 × 10 17 ions/cm 2 at an energy of 80 keV. The antibacterial effect, wear rate, and inflexion potential were measured as a function of ion dose. The results obtained indicate that copper ion implantation improves the antibacterial effect and wear behaviour for all the three medical materials studied. However, corrosion resistance decreases after ion implantation of copper. Experimental results indicate that the antibacterial property and corrosion resistance should be balanced for medical titanium materials. The marked deteriorated corrosion resistance of 317 L suggests that copper implantation may not be an effective method of improving its antibacterial activity.

  5. Bacterial adhesion on ion-implanted stainless steel surfaces

    NASA Astrophysics Data System (ADS)

    Zhao, Q.; Liu, Y.; Wang, C.; Wang, S.; Peng, N.; Jeynes, C.

    2007-08-01

    Stainless steel disks were implanted with N +, O + and SiF 3+, respectively at the Surrey Ion Beam Centre. The surface properties of the implanted surfaces were analyzed, including surface chemical composition, surface topography, surface roughness and surface free energy. Bacterial adhesion of Pseudomonas aeruginosa, Staphylococcus epidermidis and Staphylococcus aureus, which frequently cause medical device-associated infections was evaluated under static condition and laminar flow condition. The effect of contact time, growth media and surface properties of the ion-implanted steels on bacterial adhesion was investigated. The experimental results showed that SiF 3+-implanted stainless steel performed much better than N +-implanted steel, O +-implanted steel and untreated stainless steel control on reducing bacterial attachment under identical experimental conditions.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Effects of ion beam mixing on the formation of SiGe nanocrystals by ion implantation

    SciTech Connect

    Zhu, J.G.; White, C.W.; Budai, J.D.; Withrow, S.P.; Henderson, D.O.

    1996-06-01

    Nanocrystals of SiGe alloy have been formed inside a SiO{sub 2} matrix by the ion implantation technique. It is demonstrated that the sequence of implantation of Si and Ge ions affects the nanocrystal formation significantly. This is explained by the ion beam mixing effect during sequential implantation. The size distributions of the SiGe nanocrystals can also be controlled by annealing conditions.

  12. Dopant activation in ion implanted silicon by microwave annealing

    SciTech Connect

    Alford, T. L.; Thompson, D. C.; Mayer, J. W.; Theodore, N. David

    2009-12-01

    Microwaves are used as a processing alternative for the electrical activation of ion implanted dopants and the repair of ion implant damage within silicon. Rutherford backscattering spectra demonstrate that microwave heating reduces the damage resulting from ion implantation of boron or arsenic into silicon. Cross-section transmission electron microscopy and selective area electron diffraction patterns demonstrate that the silicon lattice regains nearly all of its crystallinity after microwave processing of arsenic implanted silicon. Sheet resistance readings indicate the time required for boron or arsenic electrical activation within implanted silicon. Hall measurements demonstrate the extent of dopant activation after microwave heating of implanted silicon. Physical and electrical characterization determined that the mechanism of recrystallization in arsenic implanted silicon is solid phase epitaxial regrowth. The boron implanted silicon samples did not result in enough lattice damage to amorphize the silicon lattice and resulted in low boron activation during microwave annealing even though recrystallization of the Si lattice damage did take place. Despite low boron activation levels, the level of boron activation in this work was higher than that expected from traditional annealing techniques. The kinetics of microwave heating and its effects on implanted Si are also discussed.

  13. A decaborane ion source for high current implantation

    NASA Astrophysics Data System (ADS)

    Perel, Alex S.; Loizides, William K.; Reynolds, William E.

    2002-02-01

    Progressive semiconductor device scaling in each technology node requires the formation of shallower junctions, and thus lower energy implants. The difficulties associated with extraction and transport of low energy beams often result in a loss in wafer throughput. Implantation of boron using the molecular compound decaborane has been found to allow for the shallow implantation of boron without a significant design change in the implanter. The decaborane molecule has 10 boron atoms and 14 hydrogen atoms. The implanted dose is ten times the electrical dose and the implanted depth is equivalent to the depth of a boron beam at 1/11th of the extraction energy. This advantage can only be exploited with an ion source that does not destroy the fragile molecule. We report on the design of an ion source capable of ionizing decaborane without significant fragmentation of the molecule. After it was shown that the decaborane molecule fragments above 350 °C an ion source was designed to prevent thermal dissociation of the molecule. Competitive boron dose rates were achieved using this source in a commercial high current implanter. In addition, evidence is shown that a decaborane dimer is formed in the ion source and can be implanted.

  14. Caborane beam from ITEP Bernas ion source for semiconductor implanters

    SciTech Connect

    Seleznev, D.; Hershcovitch, A.; Kropachev, G.; Kozlov, A.; Kuibeda, R.; Koshelev, V.; Kulevoy, T.; Jonson, B.; Poole, J.; Alexeyenko, O.; Gurkova, E.; Oks, E.; Gushenets, V.; Polozov, S.; Masunov, E.

    2010-02-01

    A joint research and development of steady state intense boron ion sources for hundreds of electron-volt ion implanters has been in progress for the past 5 years. The difficulties of extraction and transportation of low energy boron beams can be solved by implanting clusters of boron atoms. In Institute for Theoretical and Experimental Physics (ITEP) the Bernas ion source successfully generated the beam of decaborane ions. The carborane (C{sub 2}B{sub 10}H{sub 12}) ion beam is more attractive material due to its better thermal stability. The results of carborane ion beam generation are presented. The result of the beam implantation into the silicon wafer is presented as well.

  15. 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.

  16. 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.

  17. Behavior of PET implanted by Ti, Ag, Si and C ion using MEVVA implantation

    NASA Astrophysics Data System (ADS)

    Wu, Yuguang; Zhang, Tonghe; Zhang, Yanwen; Zhang, Huixing; Zhang, Xiaoji; Zhou, Gu

    2001-01-01

    Polyethylene terephthalane (PET) has been modified with Ti, Ag, Si and C ions from a metal vapor arc source (MEVVA). Ti, Ag, Si and C ions were implanted with acceleration voltage 40 kV to fluences ranging from 1×10 16 to 2×10 17 cm -2. The surface of implanted PET darkened with increasing ion dose, when the metal ion dose was greater than 1×10 17 cm -2 the color changed to metallic bright. The surface resistance decreases by 5-6 orders of magnitude with increasing dose. The resistivity is stable after long-term storage. The depth of Ti- and Ag-implanted layer is approximately 150 and 80 nm measured by Rutherford backscattering (RBS), respectively. TEM photos revealed the presence of Ti and Ag nano-meter particles on the surface resulting from the high-dose implantation. Ti and Ag ion implantations improved conductivity and wear resistance significantly. The phase and structural changes were obtained by X-ray diffraction (XRD). It can be seen that nano-meter particles of Ti precipitation, TiO 2 and Ti-carbides have been formed in implanted layer. Nano-hardness of implanted PET has been measured by a nano-indenter. The results show that the surface hardness, modulus and wear resistance could be increased.

  18. Experiments and Theory of Ablation Plasma Ion Implantation

    NASA Astrophysics Data System (ADS)

    Gilgenbach, R. M.; Qi, B.; Lau, Y. Y.; Johnston, M. D.; Doll, G. L.; Lazarides, A.

    2000-10-01

    Research is underway to accelerate laser ablation plume ions for implantation into substrates. Ablation plasma ion implantation (APII) biases the deposition substrate to a large negative voltage. APII has the advantages of direct acceleration and implantation of ions from metals or any other solid targets. This process is environmentally friendly because it avoids the use of toxic gaseous precursors. Initial experiments are directed towards the implantation of iron ions into silicon substrates at negative voltages from 2-10 kV. A KrF laser ablates iron targets at pulse energies up to 600 mJ and typical repetition rates of 10 Hz. Parameters which can be varied include laser fluence, relative timing of laser and high voltage pulse, and target-to-substrate distance. Spectroscopic diagnostics yield Fe plasma plume electron temperatures up to about 10 eV. Analysis of films will compare surface morphology, hardness and adhesion between deposited Vs accelerated-implanted plumes. A simple one dimensional theory is developed [1] to calculate the implanted ion current, extracted from the ion matrix sheath, as a function of time for various substrate-plume separations. This model accurately recovers Lieberman's classic results when the plume front is initially in contact with the substrate. [1] B. Qi, Y. Y. Lau, and R. M. Gilgenbach, Appl. Phys. Lett. (to be published). * This research is supported by the National Science Foundation.

  19. 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.

  20. Optical imaging and information storage in ion implanted ferroelectric ceramics

    SciTech Connect

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

    1981-11-01

    Photographic images can be stored in ferroelectric-phase lead lanthanum zirconate titanate (PLZT) ceramics using a novel photoferroelectric effect. These images are nonvolatile but erasable and can be switched from positive to negative by application of an electric field. We have found that the photosensitivity of ferroelectric PLZT is dramatically improved by ion implantation into the surface exposed to image light. For example, the intrinsic photosensitivity to near-UV light is increased by as much as four orders of magnitude by coimplantation with Ar and Ne. The increased photosensitivity results from implantation-induced decreases in dark conductivity and dielectric constant in the implanted layer. Furthermore, the increased photoferroelectric sensitivity has recently been extended from the near-UV to the visible spectrum by implants of Al and Cr. Ion-implanted PLZT is the most sensitive, nonvolatile, selectively-erasable image storage medium currently known.

  1. Amorphization and defect recombination in ion implanted silicon carbide

    SciTech Connect

    Grimaldi, M.G.; Calcagno, L.; Musumeci, P.; Frangis, N.; Van Landuyt, J.

    1997-06-01

    The damage produced in silicon carbide single crystals by ion implantation was investigated by Rutherford backscattering channeling and transmission electron microscopy techniques. Implantations were performed at liquid nitrogen and at room temperatures with several ions to examine the effect of the ion mass and of the substrate temperature on the damaging process. The damage accumulation is approximately linear with fluence until amorphization occurs when the elastic energy density deposited by the ions overcomes a critical value. The critical energy density for amorphization depends on the substrate temperature and is greatest at 300 K indicating that defects recombination occurs already at room temperature. Formation of extended defects never occurred and point defects and uncollapsed clusters of point defects were found before amorphization even in the case of light ion implantation. The atomic displacement energy has been estimated to be {approximately}12 eV/atom from the analysis of the damage process in dilute collision cascades. {copyright} {ital 1997 American Institute of Physics.}

  2. Photosensitivity enhancement of PLZT ceramics by positive ion implantation

    SciTech Connect

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

    1983-07-05

    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 X 10/sup 12/ to 1 X 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.

  3. Photosensitivity enhancement of PLZT ceramics by positive-ion implantation

    SciTech Connect

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

    1982-01-28

    The photosensitivity of lead lanthanum zirconate titanate (PLZT) ceramic material used in high resolution, high contrast, and nonvolatile 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 x 10/sup 12/ to 1 x 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.

  4. Photosensitivity enhancement of PLZT ceramics by positive ion implantation

    DOEpatents

    Land, Cecil E.; Peercy, Paul S.

    1983-01-01

    The photosensitivity of lead lanthanum zirconate titanate (PLZT) ceramic material used in high resolution, high contrast, and non-volatile photoferroelectric image storage and display devices is enhanced significantly by positive ion implantation of the PLZT near its surface. Implanted ions include H.sup.+, He.sup.+, Ne.sup.+, Ar.sup.+, as well as chemically reactive ions from Fe, Cr, and Al. The positive ion implantation advantageously serves to shift the absorption characteristics of the PLZT material from near-UV light to visible light. As a result, photosensitivity enhancement is such that the positive ion implanted PLZT plate is sensitive even to sunlight and conventional room lighting, such as fluorescent and incandescent light sources. The method disclosed includes exposing the PLZT plate to the positive ions at sufficient density, from 1.times.10.sup.12 to 1.times.10.sup.17, and with sufficient energy, from 100 to 500 KeV, to provide photosensitivity enhancement. The PLZT material may have a lanthanum content ranging from 5 to 10%, a lead zirconate content of 62 to 70 mole %, and a lead titanate content of 38 to 30%. The ions are implanted at a depth of 0.1 to 2 microns below the surface of the PLZT plate.

  5. Plasma sheath physics and dose uniformity in enhanced glow discharge plasma immersion ion implantation and deposition

    SciTech Connect

    Li Liuhe; Li Jianhui; Kwok, Dixon T. K.; Chu, Paul K.; Wang Zhuo

    2009-07-01

    Based on the multiple-grid particle-in-cell code, an advanced simulation model is established to study the sheath physics and dose uniformity along the sample stage in order to provide the theoretical basis for further improvement of enhanced glow discharge plasma immersion ion implantation and deposition. At t=7.0 mus, the expansion of the sheath in the horizontal direction is hindered by the dielectric cage. The electron focusing effect is demonstrated by this model. Most of the ions at the inside wall of the cage are implanted into the edge of the sample stage and a relatively uniform ion fluence distribution with a large peak is observed at the end. Compared to the results obtained from the previous model, a higher implant fluence and larger area of uniformity are disclosed.

  6. Improvement of Contact Resistance with Molecular Ion Implantation

    SciTech Connect

    Lee, Kyung Won; Lee, Jin Ku; Oh, Jae Geun; Ju, Min Ae; Jeon, Seung Joon; Ku, Ja Chun; Park, Sung Ki; Huh, Tae Hoon; Kim, Steve; Ra, Geum Joo; Harris, Mark A.; Reece, Ronald N.; Yoon, Dae Ho

    2008-11-03

    Basic characteristics of ClusterBoron (B{sub 18}H{sub 22}) implantation were investigated for improving contact resistance in DRAM devices. Generally, {sup 49}BF{sub 2} has been widely used for contact implant application in DRAM manufacturing because of its higher productivity compared to monomer boron ({sup 11}B). However, because of limited activation in a low thermal budget ({approx}800 deg. C) anneal, the sheet resistance was saturated for doses over 5x10{sup 15} ions/cm{sup 2}. Although many investigations have been reported, such as {sup 30}BF implant mixed implant with monomer boron etc., no practical solution has been found for dramatic improvement of contact resistance in a productive manner. B{sub 18}H{sub 22} was developed to overcome the productivity limitations encountered in low energy, high dose boron implantation and the limited activation of {sup 49}BF{sub 2} due to co-implanted fluorine. In this study, basic characterization of the B{sub 18}H{sub 22} contact implant was performed through sheet resistance, SIMS (Secondary Ion Mass Spectrometry) and XTEM (cross-sectional transmission electron microscopy). The B{sub 18}H{sub 22} implants showed lower sheet resistance than conventional {sup 49}BF{sub 2} for 5x10{sup 15} ions/cm{sup 2} on bare wafer tests. Through XTEM study, we found the activation behavior of both B{sub 18}H{sub 22} and {sup 49}BF{sub 2} were directly related with the amorphous layer thickness and residual defects from low thermal budget anneal. PMOS contact resistance in the sub-70 nm device by B{sub 18}H{sub 22} implantation showed considerable improvement (about 30%), showing B{sub 18}H{sub 22} could replace the BF{sub 2} for contact implant in contact resistance implant.

  7. Plasma Source Ion Implantation of Aluminum and Aluminum Alloys

    NASA Astrophysics Data System (ADS)

    Walter, Kevin Carl

    Three plasma source ion implantation (PSII) schemes applied to three aluminum systems have been studied. Pure aluminum, and aluminum alloys 7075 (Al-Cu-Mg-Zn) and A390 (Al-17Si-Cu-Fe) were (1) argon ion sputter-cleaned and nitrogen-implanted, (2) nitrogen-implanted without sputter -cleaning, and (3) argon-implanted. Nitrogen implantation was performed with the goal of modifying the surface properties by transformation of the surface to aluminum-nitride. Argon implantation was performed with the goal of modifying the surface properties by inducing radiation damage. All implantation schemes were accomplished using a glow discharge mode of the PSII process. Implanted surfaces were investigated using Auger depth profiling and Transmission Electron Microscopy. The profiles indicated a stoichiometric layer, ~ 0.15 μm thick, of AlN on the nitrogen-implanted samples. Electron microscopy confirmed the complete conversion of the aluminum surface to AlN. Knoop microhardness tests showed an increase in surface hardness, especially at low loads. The improvements were independent of prior sputter-cleaning and were approximately equal for the studied aluminum systems. Pin-on-disk wear tests were conducted using a ruby stylus and isopropanol lubrication. Argon implantation decreased the wear resistance of pure aluminum and 7075. Nitrogen implantation improved the wear rates by a factor of ~10 for pure aluminum and 7075. These improvements were independent of prior sputter-cleaning. The coefficient of friction was not significantly influenced by the implantation schemes. Due to a coarse microstructure, tribological tests of ion-implanted A390 were inconclusive. Corrosion studies performed in a 3.5 wt% NaCl solution (seawater) indicated nitrogen implantation gave pure aluminum improved corrosion resistance. The improvement is due to the complete conversion of the aluminum surface to AlN. Because of pre-existing precipitates, the corrosion properties of 7075 and A390 were not

  8. 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. PMID:26961491

  9. The Behavior of Ion-Implanted Hydrogen in Gallium Nitride

    SciTech Connect

    Myers, S.M.; Headley, T.J.; Hills, C.R.; Han, J.; Petersen, G.A.; Seager, C.H.; Wampler, W.R.

    1999-01-07

    Hydrogen was ion-implanted into wurtzite-phase GaN, and its transport, bound states, and microstructural effects during annealing up to 980 C were investigated by nuclear-reaction profiling, ion-channeling analysis, transmission electron microscopy, and infrared (IR) vibrational spectroscopy. At implanted concentrations 1 at.%, faceted H{sub 2} bubbles formed, enabling identification of energetically preferred surfaces, examination of passivating N-H states on these surfaces, and determination of the diffusivity-solubility product of the H. Additionally, the formation and evolution of point and extended defects arising from implantation and bubble formation were characterized. At implanted H concentrations 0.1 at.%, bubble formation was not observed, and ion-channeling analysis indicated a defect-related H site located within the [0001] channel.

  10. Nanocrystal formation via yttrium ion implantation into sapphire

    SciTech Connect

    Hunt, E.M.; Hampikian, J.M.; Poker, D.B.

    1995-12-31

    Ion implantation has been used to form nanocrystals in the near surface of single crystal {alpha}-Al{sub 2}O{sub 3}. The ion fluence was 5 x 10{sup 16} Y{sup +}/cm{sup 2}, and the implant energies investigated were 100, 150, and 170 keV. The morphology of the implanted region was investigated using transmission electron microscopy, x-ray energy dispersive spectroscopy, Rutherford backscattering spectroscopy and ion channeling. The implantation causes the formation of an amorphous surface layer which contains spherical nanosized crystals with a diameter of {approximately}13 nm. The nanocrystals are randomly oriented and exhibit a face-centered cubic structure with a lattice parameter of {approximately}4.1 A {+-} .02 A. Preliminary chemical analysis shows that these nanocrystals are rich in aluminum and yttrium and poor in oxygen relative to the amorphous matrix.

  11. Bioactivity of Mg-ion-implanted zirconia and titanium

    NASA Astrophysics Data System (ADS)

    Liang, H.; Wan, Y. Z.; He, F.; Huang, Y.; Xu, J. D.; Li, J. M.; Wang, Y. L.; Zhao, Z. G.

    2007-01-01

    Titanium and zirconia are bioinert materials lacking bioactivity. In this work, surface modification of the two typical biomaterials is conducted by Mg-ion-implantation using a MEVVA ion source in an attempt to increase their bioactivity. Mg ions were implanted into zirconia and titanium with fluences ranging from 1 × 10 17 to 3 × 10 17 ions/cm 2 at 40 keV. The Mg-implanted samples, as well as control (unimplanted) samples, were immersed in SBF for 7 days and then removed to identify the presence of calcium and phosphate (Ca-P) coatings and to characterize their morphology and structure by SEM, XRD, and FT-IR. SEM observations confirm that globular aggregates are formed on the surfaces of the Mg-implanted zirconia and titanium while no precipitates are observed on the control samples. XRD and FT-IR analyses reveal that the deposits are carbonated hydroxyapatite (HAp). Our experimental results demonstrate that Mg-implantation improves the bioactivity of zirconia and titanium. Further, it is found that the degree of bioactivity is adjustable by the ion dose. Mechanisms are proposed to interpret the improvement of bioactivity as a result of Mg implantation and the difference in bioactivity between zirconia and titanium.

  12. 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.

  13. Influence of Oxygen Ion Implantation on the Damage and Annealing Kinetics of Iron-Implanted Sapphire

    SciTech Connect

    Hunn, J.D.; McHargue, C.J.

    1999-11-14

    The effects of implanted oxygen on the damage accumulation in sapphire which was previously implanted with iron was studied for (0001) sapphire implanted with iron and then with oxygen. The energies were chosen to give similar projected ranges. One series was implanted with a 1:l ratio (4x10{sup 16} ions/cm{sup 2} each) and another with a ratio of 2:3 (4x10{sup 16} fe{sup +}/cm{sup 2}; 6x10{sup 16} O{sup +}/cm{sup 2}). Retained damage, X, in the Al-sublattice, was compared to that produced by implantation of iron alone. The observed disorder was less for the dual implantations suggesting that implantation of oxygen enhanced dynamic recovery during implantation. Samples were annealed for one hour at 800 and 1200 C in an oxidizing and in a reducing atmosphere. No difference was found in the kinetics of recovery in the Al-sublattice between the two dual implant conditions. However, the rate of recovery was different for each from samples implanted with iron alone.

  14. Metal plasma immersion ion implantation and deposition: A review

    SciTech Connect

    Anders, A.

    1996-09-01

    Metal Plasma Immersion Ion Implantation and Deposition (MePIIID) is a hybrid process combining cathodic arc deposition and plasma immersion ion implantation. The properties of metal plasma produced by vacuum arcs are reviewed and the consequences for MePIIID are discussed. Different version of MePIIID are described and compared with traditional methods of surface modification such as ion beam assisted deposition (IBAD). MePIIID is a very versatile approach because of the wide range of ion species and energies used. In one extreme case, films are deposited with ions in the energy range 20--50 eV, and at the other extreme, ions can be implanted with high energy (100 keV or more) without film deposition. Novel features of the technique include the use of improved macroparticle filters; the implementation of several plasma sources for multi-element surface modification; tuning of ion energy during implantation and deposition to tailor the substrate-film intermixed layer and structure of the growing film; simultaneous pulsing of the plasma potential (positive) and substrate bias (negative) with a modified Marx generator; and the use of high ion charge states.

  15. 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.

  16. 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.

  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. Thin hydroxyapatite surface layers on titanium produced by ion implantation

    NASA Astrophysics Data System (ADS)

    Baumann, H.; Bethge, K.; Bilger, G.; Jones, D.; Symietz, I.

    2002-11-01

    In medicine metallic implants are widely used as hip replacement protheses or artificial teeth. The biocompatibility is in all cases the most important requirement. Hydroxyapatite (HAp) is frequently used as coating on metallic implants because of its high acceptance by the human body. In this paper a process is described by which a HAp surface layer is produced by ion implantation with a continuous transition to the bulk material. Calcium and phosphorus ions are successively implanted into titanium under different vacuum conditions by backfilling oxygen into the implantation chamber. Afterwards the implanted samples are thermally treated. The elemental composition inside the implanted region was determined by nuclear analysis methods as (α,α) backscattering and the resonant nuclear reaction 1H( 15N,αγ) 12C. The results of X-ray photoelectron spectroscopy indicate the formation of HAp. In addition a first biocompatibility test was performed to compare the growing of marrow bone cells on the implanted sample surface with that of titanium.

  19. Nitrogen and boron ion implantation into electrodeposited hard chrome

    SciTech Connect

    Walter, K.C.; Tesmer, J.R.; Scarborough, W.K.; Woodring, J.S.; Nastasi, M.; Kern, K.T.

    1996-10-01

    Electrodeposited hard chrome was ion implanted with N alone, B alone, and a combination. Separate N and B implantation was done at 75 keV and incident doses of 2, 4, and 8x10{sup 17} at/cm{sup 2}. Samples with both N/B implants used 75 keV and incident dose levels of 4x10{sup 17} N- and B-at/cm{sup 2}. Beam-line system was used. Retained dose was measured using ion beam analysis, which indicated most of the incident dose was retained. Surface hardness, wear coefficient, and friction coefficient were determined by nanohardness indentation and pin-on-disk wear. At a depth of 50 nm, surface hardness increased from 18{+-}1 GPa (unimplanted) to a max of 23{+-}4 GPa for B implant and 26{+-}1 GPa for N implant. the wear coefficient was reduced by 1.3x to 7.4x, depending on implantation. N implant results in lower wear coefficients than B implant.

  20. [Improve wear resistance of UHMWPE by O+ ion implanted].

    PubMed

    Xiong, Dangsheng

    2003-12-01

    Ultra high molecular weight polyethylene (UHMWPE) was implanted with 450 keV and 100 keV O+ ions at dosage of 1 x 10(15)/cm2, 5 x 10(15)/cm2, 3 x 10(14)/cm2, respectively. Its wear behaviors were studied under dry friction condition and lubrication by means of distilled water using a pin-on-disk tribometer with a Si3N4 ceramic ball as a counterface. The wear surfaces were examined with SEM. The experimental results showed that the wear rate of implanted UHMWPE is lower than that of un-implanted UHMWPE under both dry and distilled friction conditions, especially for 450 keV energy and 5 x 10(15)/cm2 dose implantation. The friction coefficient of O+ ions implanted UHMWPE is higher than that of un-implanted UHMWPE under both dry and distilled friction conditions. The adhesive, plow and plastic deformation are the wearing mechanism for un-implanted UHMWPE; the fatigue and abrasive wear are that for implanted UHMWPE. PMID:14716850

  1. 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. PMID:26504998

  2. 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.

  3. 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.

  4. Luminescence of a titanate compound under europium ion implantation

    NASA Astrophysics Data System (ADS)

    Plantevin, O.; Oliviero, E.; Dantelle, G.; Mayer, L.

    2014-05-01

    The ability to incorporate europium ions in a near-surface layer of a nonlinear optical material KTiOPO4 by ion implantation is reported here. Europium diffusion as well as surface modification were characterized after annealing using RBS. The photoluminescence of the as-implanted samples indicates that the creation of defects gives rise to green visible emission centered about 550 nm. Annealing up to 1000 °C does not allow the oxidation to the 3+ valence state of the europium ion. However it is shown that annealing up to such high temperature gives rise to an intense near infra-red photoluminescence in the range 800-1100 nm in implanted samples at an optimal fluence of 2 × 1013 europium ions/cm2.

  5. Ion implantation and rapid thermal processing of III-V nitrides

    SciTech Connect

    Zolper, J.C.; Crawford, M.H.; Pearton, S.J.; Abernathy, C.R.; Vartuli, C.B.; Yuan, C.; Stall, R.A.

    1996-05-01

    Ion implantation doping and isolation coupled with rapid thermal annealing has played a critical role in the realization of high performance photonic and electronic devices in all mature semiconductor material systems. This is also expected to be the case for the binary III-V nitrides (InN, GaN, and AlN) and their alloys as the epitaxial material quality improves and more advanced device structures are fabricated. In this article, we review the recent developments in implant doping and isolation along with rapid thermal annealing of GaN and the In-containing ternary alloys InGaN and InAlN. In particular, the successful n- and p-type doping of GaN by ion implantation of Si and Mg+P, respectively, and subsequent high temperature rapid thermal anneals in excess of 1000{degree}C is reviewed. In the area of implant isolation, N-implantation has been shown to compensate both n- and p-type GaN, N-, and O-implantation effectively compensates InAlN, and InGaN shows limited compensation with either N- or F-implantation. The effects of rapid thermal annealing on unimplanted material are also presented. 29 refs., 6 figs., 2 tabs.

  6. Status of ion implantation doping and isolation of III-V nitrides

    SciTech Connect

    Zolper, J.C.; Pearton, S.J.; Abernathy, C.R.

    1995-09-01

    Ion implantation doping and isolation has played a critical role in the realization of high performance photonic and electronic devices in all mature semiconductor material systems. This is also expected to be the case for the binary III-V nitrides (InN, GaN, and AlN) and their alloys as the epitaxial material quality improves and more advanced device structures are fabricated. With this in mind, we review the status of implant doping and isolation of GaN and the ternary alloys AlGaN, InGaN, and InAlN. In particular, we reported on the successful n- and p-type doping of GaN by ion implantation of Mg+P and Si, respectively, and subsequent high temperature rapid thermal anneals in excess of 1000{degrees}C. In the area of implant isolation, N-implantation has been shown to compensate both n- and p-type GaN, N and O-implantation effectively compensates InAlN, and InGaN shows limited compensation with either N or F implantation.

  7. Ion implantation and rapid thermal processing of Ill-V nitrides

    NASA Astrophysics Data System (ADS)

    Zolper, J. C.; Hagerott Crawford, M.; Pearton, S. J.; Abernathy, C. R.; Vartuli, C. B.; Yuan, C.; Stall, R. A.

    1996-05-01

    Ion implantation doping and isolation coupled with rapid thermal annealing has played a critical role in the realization of high performance photonic and electronic devices in all mature semiconductor material systems. This is also expected to be the case for the binary III-V nitrides (InN, GaN, and A1N) and their alloys as the epitaxial material quality improves and more advanced device structures are fabricated. In this article, we review the recent developments in implant doping and isolation along with rapid thermal annealing of GaN and the In-containing ternary alloys InGaN and InAlN. In particular, the successful n- and p-type doping of GaN by ion implantation of Si and Mg+P, respectively, and subsequent high temperature rapid thermal anneals in excess of 1000°C is reviewed. In the area of implant isolation, N-implantation has been shown to compensate both n- and p-type GaN, N-, and O-implantation effectively compensates InAlN, and InGaN shows limited compensation with either N- or F-implantation. The effects of rapid thermal annealing on unimplanted material are also presented.

  8. 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. PMID:19332400

  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. PMID:24789983

  10. Photosensitivity and imaging characteristics of ion-implanted PLZT ceramics

    SciTech Connect

    Land, C.E.

    1985-01-01

    We reported in previous papers that both the near-uv and the visible photosensitivities of ferroelectric-phase PLZT (lead lanthanum zirconate titanate) ceramics are increased by as much as four orders of magnitude by ion implantation or a combination of thermal diffusion of Al and ion implantation. New results are presented here on high-energy (1 MeV) implants of Al and Ni and coimplants of Al + Ne and Ni + Ne, and these results are compared with earlier 500 keV implants of Al and Cr and coimplants of Al + Ne and Cr + Ne as surface modification techniques for increasing the visible photosensitivity of PLZT. The important role of grain size in determining optimum contrast and resolution of stored optical information is described in terms of new experimental results.

  11. Al-O interactions in ion-implanted crystalline silicon

    NASA Astrophysics Data System (ADS)

    Galvagno, G.; La Ferla, A.; Spinella, C.; Priolo, F.; Raineri, V.; Torrisi, Lucio; Rimini, E.; Carnera, A.; Gasparotto, A.

    1994-08-01

    The formation and dissolution of Si-O-Al precipitates have been investigated in Czochralski silicon wafers implanted with 6 MeV Al ions and thermally processed. The data have been compared to the O precipitation in samples implanted with 6 MeV Si or P ions. The amount of precipitated O atoms is about one order of magnitude higher for Al than for Si or P implanted samples. Moreover, a strong gettering of the Al atoms by the silicon dioxide precipitates has been observed. The precipitate evolution has been studied for different annealing times and temperatures. The oxygen precipitation has been simulated by the classical theory of nucleation and growth, with the introduction of new factors that take into account the implant damage distribution, the agglomeration of point defects during the initial stages of the annealing and the oxygen outdiffusion from the sample surface.

  12. Laser-driven ion sources for metal ion implantation for the reduction of dry friction

    SciTech Connect

    Boody, F. P.; Juha, L.; Kralikova, B.; Krasa, J.; Laska, L.; Masek, K.; Pfeifer, M.; Rohlena, K.; Skala, J.; Straka, P.; Perina, V.; Woryna, E.; Giersch, D.; Hoepfl, R.; Kelly, J. C.; Hora, H.

    1997-04-15

    The anomalously high ion currents and very high ionization levels of laser-produced plasmas give laser-driven ion sources significant advantages over conventional ion sources. In particular, laser-driven ion sources should provide higher currents of metal ions at lower cost, for implantation into solids in order to improve their material properties such as friction. The energy and charge distributions for Pb and Sn ions produced by ablation of solid targets with {approx}25 J, {approx}300 ps iodine laser pulses, resulting in up to 48-times ionized MeV ions, as well as the optimization of focus position, are presented. Implantation of these ions into Ck-45 steel, without electrostatic acceleration, produced profiles with two regions. Almost all of the ions were implanted in a near surface region a few nm deep. However, a small but significant number of ions were implanted as deep as could be measured with Rutherford backscattering (RBS), here 150 nm for Sn and 250 nm for Pb. For the implanted ion densities and profiles achieved, no change in the coefficient of friction was measured for either ion.

  13. 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.

  14. 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.

  15. On carbon nitride synthesis at high-dose ion implantation

    NASA Astrophysics Data System (ADS)

    Romanovsky, E. A.; Bespalova, O. V.; Borisov, A. M.; Goryaga, N. G.; Kulikauskas, V. S.; Sukharev, V. G.; Zatekin, V. V.

    1998-04-01

    Rutherford backscattering spectrometry was used for the study of high dose 35 keV nitrogen ions implantation into graphites and glassy carbon. Quantitative data on depth profiles and its dependencies on irradiation fluence and ion beam density were obtained. The stationary dome-shaped depth profile with maximum nitrogen concentration 22-27 at.% and half-width more than twice exceeding projected range of ions is reached at fluence Φ ˜10 18 cm -2. The dependence of the maximum concentration in the profile on ion current density was studied. The largest concentration was obtained at reduced ion current density.

  16. Maximizing cochlear implant patients' performance with advanced speech training procedures.

    PubMed

    Fu, Qian-Jie; Galvin, John J

    2008-08-01

    Advances in implant technology and speech processing have provided great benefit to many cochlear implant patients. However, some patients receive little benefit from the latest technology, even after many years' experience with the device. Moreover, even the best cochlear implant performers have great difficulty understanding speech in background noise, and music perception and appreciation remain major challenges. Recent studies have shown that targeted auditory training can significantly improve cochlear implant patients' speech recognition performance. Such benefits are not only observed in poorly performing patients, but also in good performers under difficult listening conditions (e.g., speech noise, telephone speech, music, etc.). Targeted auditory training has also been shown to enhance performance gains provided by new implant devices and/or speech processing strategies. These studies suggest that cochlear implantation alone may not fully meet the needs of many patients, and that additional auditory rehabilitation may be needed to maximize the benefits of the implant device. Continuing research will aid in the development of efficient and effective training protocols and materials, thereby minimizing the costs (in terms of time, effort and resources) associated with auditory rehabilitation while maximizing the benefits of cochlear implantation for all recipients. PMID:18295992

  17. Recent advances in micro/nanoscale biomedical implants.

    PubMed

    Arsiwala, Ammar; Desai, Preshita; Patravale, Vandana

    2014-09-10

    The medical device industry is growing at a very fast pace and has recorded great research activity over the past decade. The interdisciplinary nature of this field has made it possible for researchers to incorporate principles from various allied areas like pharmaceutics, bioengineering, biotechnology, chemistry, electronics, biophysics etc. to develop superior medical solutions, offering better prospects to the patient. Moreover, micro and nanotechnology have made it possible to positively affect at the sub-micron scales, the cellular processes initiated upon implantation. Literature is rife with findings on various implants and this review comprehensively summarizes the recent advances in micro/nanoscale implantable medical devices - particularly cardiovascular implants, neural implants, orthopedic and dental implants and other miscellaneous implants. Over the years, medical implants have metamorphosed from mere support providing devices to smart interventions participating positively in the healing process. We have highlighted the current research in each area emphasizing on the value addition provided by micro/nanoscale features, its course through the past and the future perspectives focusing on the unmet needs. PMID:24960225

  18. Optical image storage in ion implanted PLZT ceramics

    SciTech Connect

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

    1980-01-01

    Optical images can be stored in transparent lead-lanthanum-zirconate-titanate (PLZT) ceramics by exposure to near-uv light with photon energies greater than the band gas energy of approx. 3.35 eV. The image storage process relies on optically induced changes in the switching properties of ferroelectric domains (photoferroelectric effect). Stored images are nonvolatile but can be erased by uniform uv illumination and simultaneous application of an electric field. Although high quality images, with contrast variations of greater than or equal to 100:1 and spatial resolution of approx. 10 ..mu..m, can be stored using the photoferroelectric effect, relatively high exposure energies (approx. 100 mJ/cm/sup 2/) are required to store these images. This large exposure energy severely limits the range of possible applications of nonvolatile image storage in PLZT ceramics. It was found in H, He, and Ar implanted PLZT that the photosensitivity can be significantly increased by ion implantation into the surface to be exposed. The photosensitivity after implantation with 5 x 10/sup 14/ 500 keV Ar/cm/sup 2/ is increased by about three orders of magnitude over that of unimplanted PLZT. The image storage process and the effect of ion implantation is presented along with a phenomenological model which describes the enhancement in photosensitivity obtained by ion implantation. This model takes into account both light- and ion implantation-induced changes in conductivity and gives quantitative agreement with the measured changes in the coercive voltage with light intensity for ion implanted PLZT.

  19. Influence of ion implantation on titanium surfaces for medical applications

    NASA Astrophysics Data System (ADS)

    Krischok, Stefan; Blank, Claudia; Engel, Michael; Gutt, Richard; Ecke, Gernot; Schawohl, Jens; Spieß, Lothar; Schrempel, Frank; Hildebrand, Gerhard; Liefeith, Klaus

    2007-09-01

    The implantation of ions into the near surface layer is a new approach to improve the osseointegration of metallic biomaterials like titanium. Meanwhile it is well known that surface topography and surface physico-chemistry as well as visco-elastic properties influence the cell response after implantation of implants into the human body. To optimize the cell response of titanium, ion implantation techniques have been used to integrate calcium and phosphorus, both elements present in the inorganic bone phase. In this context, the concentration profile of the detected elements and their chemical state have been investigated using X-ray photoelectron spectroscopy and Auger electron spectroscopy depth profiling. Ion implantation leads to strong changes of the chemical composition of the near surface region, which are expected to modify the biofunctionality as observed in previous experiments on the cell response. The co-implantation of calcium and phosphorus samples, which showed best results in the performed tests (biological and physical), leads to a strong modification of the chemical surface composition.

  20. Method For Silicon Surface Texturing Using Ion Implantation

    NASA Astrophysics Data System (ADS)

    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.

  1. 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.

  2. 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.

  3. Cathodoluminescence characterization of ion implanted GaAs

    NASA Astrophysics Data System (ADS)

    Cone, M. L.

    1980-03-01

    The unique properties of GaAs make it possible to construct integrated circuit devices that are impossible in Si. The Air Force Avionics Laboratory/AADR has been developing this technology for a number of years. The difficulty of introducing dopants by diffusion has lead ion implantation to play an increasing role in the fabrication process. The present production technique for high performance devices is to fabricate large quantities and select those few that meet the desired specifications. Having a nondestructive technique that can be used to characterize the implantation process during fabrication of the device so as to reject faulty device structures can save valuable time as well as money. Depth-resolved cathodoluminescence is a process that can be used for this purpose. This research develops and verifies a model of cathodoluminescence in ion implanted GaAs. This model can now be used as a tool for further study of ion implanted GaAs. This is the first step in developing cathodoluminescence as a tool for deducing the shape of the ion implanted depth profile in semiconductor materials.

  4. 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.

  5. Vertical silicon waveguide coupler bent by ion implantation.

    PubMed

    Yoshida, Tomoya; Tajima, Syougo; Takei, Ryohei; Mori, Masahiko; Miura, Noboru; Sakakibara, Youichi

    2015-11-16

    We propose and demonstrate that vertically curved waveguides (VCWs) enable vertical coupling between silicon wire waveguides and optical fibers with low wavelength dependence and polarization dependence for wide telecommunication wavelength band light. To bend these VCWs, we implanted silicon ions into silicon wire cantilevers from the vertical direction. The internal stress distribution that was induced by ion implantation drove the bending force, and we achieved vertical bending of the waveguides, with curvature radii ranging from 3 to 25 μm. At a radius of curvature of 6 μm, we obtained a coupling loss of 3 dB using a lens fiber. PMID:26698428

  6. Raman spectroscopy of ion-implanted silicon

    SciTech Connect

    Tuschel, D.D.; Lavine, J.P.

    1997-11-01

    Raman spectroscopy is used to characterize silicon implanted with boron at a dose of 10{sup 14}/cm{sup 2} or less and thermally annealed. The Raman scattering strengths and band shapes of the first-order optical mode at 520 cm{sup {minus}1} and of the second-order phonon modes are investigated to determine which modes are sensitive to the boron implant. The as-implanted samples show diminishing Raman scattering strength as the boron dose increases when the incident laser beam is 60{degree} with respect to the sample normal. Thermal annealing restores some of the Raman scattering strength. Three excitation wavelengths are used and the shortest, 457.9 nm, yields the greatest spectral differences from unimplanted silicon. The backscattering geometry shows a variety of changes in the Raman spectrum upon boron implantation. These involve band shifts of the first-order optical mode, bandwidth variations of the first-order optical mode, and the intensity of the second-order mode at 620 cm{sup {minus}1}.

  7. 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.

  8. Corrosion resistance of titanium ion implanted AZ91 magnesium alloy

    SciTech Connect

    Liu Chenglong; Xin Yunchang; Tian Xiubo; Zhao, J.; Chu, Paul K.

    2007-03-15

    Degradable metal alloys constitute a new class of materials for load-bearing biomedical implants. Owing to their good mechanical properties and biocompatibility, magnesium alloys are promising in degradable prosthetic implants. The objective of this study is to improve the corrosion behavior of surgical AZ91 magnesium alloy by titanium ion implantation. The surface characteristics of the ion implanted layer in the magnesium alloys are examined. The authors' results disclose that an intermixed layer is produced and the surface oxidized films are mainly composed of titanium oxide with a lesser amount of magnesium oxide. X-ray photoelectron spectroscopy reveals that the oxide has three layers. The outer layer which is 10 nm thick is mainly composed of MgO and TiO{sub 2} with some Mg(OH){sub 2}. The middle layer that is 50 nm thick comprises predominantly TiO{sub 2} and MgO with minor contributions from MgAl{sub 2}O{sub 4} and TiO. The third layer from the surface is rich in metallic Mg, Ti, Al, and Ti{sub 3}Al. The effects of Ti ion implantation on the corrosion resistance and electrochemical behavior of the magnesium alloys are investigated in simulated body fluids at 37{+-}1 deg. C using electrochemical impedance spectroscopy and open circuit potential techniques. Compared to the unimplanted AZ91 alloy, titanium ion implantation significantly shifts the open circuit potential (OCP) to a more positive potential and improves the corrosion resistance at OCP. This phenomenon can be ascribed to the more compact surface oxide film, enhanced reoxidation on the implanted surface, as well as the increased {beta}-Mg{sub 12}Al{sub 17} phase.

  9. A high-energy, high-current ion implantation system

    NASA Astrophysics Data System (ADS)

    Rose, Peter H.; Faretra, Ronald; Ryding, Geoffery

    1985-01-01

    High current (Pre-DepTM) ion implanters, operating at 80 keV, have met a need in the semiconductor industry. For certain processes, higher energies are required, either to penetrate a surface layer or to place the dopant ion at a greater depth. The Eaton/Nova Model NV10-160 Pre-DepTM Ion Implanter has been developed to meet those special needs. Beam currents as high as 10.0 mA are available at energies up to 160 keV for routine production applications. The system has also been qualified for low current, low dose operation (1011 ions cm-2) and this unique versatility provides the Process and Equipment Engineers with a powerful new tool. The Model NV10-160 also utilizes the Nova-designed, double disk interchange processing system to minimize inactive beam time so that wafer throughputs, up to 300 wafers/h, are achievable on a routine basis. DatalockTM, a computer driven implant monitoring system and AT-4, the Nova cassette-to-cassette wafer loader, are available as standard options. As a production machine, the Model NV10-160 with its high throughput capability, will reduce the implant cost per wafer significantly for doses above 10 × 1015 ions/cm2. Performance patterns are now emerging as some twenty-five systems have now been shipped. This paper summarizes the more important characteristics and reviews the major design features of the NV10-160.

  10. High definition surface micromachining of LiNbO 3 by ion implantation

    NASA Astrophysics Data System (ADS)

    Chiarini, M.; Bentini, G. G.; Bianconi, M.; De Nicola, P.

    2010-10-01

    High Energy Ion Implantation (HEII) of both medium and light mass ions has been successfully applied for the surface micromachining of single crystal LiNbO 3 (LN) substrates. It has been demonstrated that the ion implantation process generates high differential etch rates in the LN implanted areas, when suitable implantation parameters, such as ion species, fluence and energy, are chosen. In particular, when traditional LN etching solutions are applied to suitably ion implanted regions, etch rates values up to three orders of magnitude higher than the typical etching rates of the virgin material, are registered. Further, the enhancement in the etching rate has been observed on x, y and z-cut single crystalline material, and, due to the physical nature of the implantation process, it is expected that it can be equivalently applied also to substrates with different crystallographic orientations. This technique, associated with standard photolithographic technologies, allows to generate in a fast and accurate way very high aspect ratio relief micrometric structures on LN single crystal surface. In this work a description of the developed technology is reported together with some examples of produced micromachined structures: in particular very precisely defined self sustaining suspended structures, such as beams and membranes, generated on LN substrates, are presented. The developed technology opens the way to actual three dimensional micromachining of LN single crystals substrates and, due to the peculiar properties characterising this material, (pyroelectric, electro-optic, acousto-optic, etc.), it allows the design and the production of complex integrated elements, characterised by micrometric features and suitable for the generation of advanced Micro Electro Optical Systems (MEOS).

  11. 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.

  12. Biologic stability of plasma ion-implanted miniscrews

    PubMed Central

    Cho, Young-Chae; Cha, Jung-Yul; Hwang, Chung-Ju; Park, Young-Chel; Jung, Han-Sung

    2013-01-01

    Objective To gain basic information regarding the biologic stability of plasma ion-implanted miniscrews and their potential clinical applications. Methods Sixteen plasma ion-implanted and 16 sandblasted and acid-etched (SLA) miniscrews were bilaterally inserted in the mandibles of 4 beagles (2 miniscrews of each type per quadrant). Then, 250 - 300 gm of force from Ni-Ti coil springs was applied for 2 different periods: 12 weeks on one side and 3 weeks contralaterally. Thereafter, the animals were sacrificed and mandibular specimens including the miniscrews were collected. The insertion torque and mobility were compared between the groups. The bone-implant contact and bone volume ratio were calculated within 800 µm of the miniscrews and compared between the loading periods. The number of osteoblasts was also quantified. The measurements were expressed as percentages and analyzed by independent t-tests (p < 0.05). Results No significant differences in any of the analyzed parameters were noted between the groups. Conclusions The preliminary findings indicate that plasma ion-implanted miniscrews have similar biologic characteristics to SLA miniscrews in terms of insertion torque, mobility, bone-implant contact rate, and bone volume rate. PMID:23814706

  13. An RFQ accelerator system for MeV ion implantation

    NASA Astrophysics Data System (ADS)

    Hirakimoto, Akira; Nakanishi, Hiroaki; Fujita, Hiroyuki; Konishi, Ikuo; Nagamachi, Shinji; Nakahara, Hiroshi; Asari, Masatoshi

    1989-02-01

    A 4-vane-type Radio-Frequency Quadrupole (RFQ) accelerator system for MeV ion implantation has been constructed and ion beams of boron and nitrogen have been accelerated successfully up to an energy of 1.01 and 1.22 MeV, respectively. The acceleration of phosphorus is now ongoing. The design was performed with two computer codes called SUPERFISH and PARMTEQ. The energy of the accelerated ions was measured by Rutherford backscattering spectroscopy. The obtained values agreed well with the designed ones. Thus we have confirmed the validity of our design and have found the possibility that the present RFQ will break through the production-use difficulty of MeV ion implantation.

  14. Ion implantation induced swelling in 6H-SiC

    SciTech Connect

    Nipoti, R.; Albertazzi, E.; Bianconi, M.; Lotti, R.; Lulli, G.; Cervera, M.; Carnera, A.

    1997-06-01

    Ion implantation induced surface expansion (swelling) of 6H-SiC was investigated through the measurement of the step height between implanted and unimplanted areas. The samples were irradiated at room temperature with 500 keV Al{sup +} ions in the dose range 1.25{times}10{sup 14}{endash}3{times}10{sup 15}ionscm{sup {minus}2}. Swelling was related to dose and the area density of ion-induced damage measured by Rutherford backscattering channeling technique. The observed trend is consistent with the hypothesis that the volume expansion of the ion damaged crystal is proportional to the area density of displaced atoms, plus an additional relaxation occurring at the onset of the crystalline to amorphous transition. {copyright} {ital 1997 American Institute of Physics.}

  15. p type doping of zinc oxide by arsenic ion implantation

    SciTech Connect

    Braunstein, G.; Muraviev, A.; Saxena, H.; Dhere, N.; Richter, V.; Kalish, R.

    2005-11-07

    p type doping of polycrystalline ZnO thin films, by implantation of arsenic ions, is demonstrated. The approach consisted of carrying out the implantations at liquid-nitrogen temperature ({approx}-196 deg. C), followed by a rapid in situ heating of the sample, at 560 deg. C for 10 min, and ex situ annealing at 900 deg. C for 45 min in flowing oxygen. p type conductivity with a hole concentration of 2.5x10{sup 13} cm{sup -2} was obtained using this approach, following implantation of 150 keV 5x10{sup 14} As/cm{sup 2}. A conventional room-temperature implantation of 1x10{sup 15} As/cm{sup 2}, followed by the same ex situ annealing, resulted in n type conductivity with a carrier concentration of 1.7x10{sup 12} cm{sup -2}.

  16. 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.

  17. Erbium ion implantation into different crystallographic cuts of lithium niobate

    NASA Astrophysics Data System (ADS)

    Nekvindova, P.; Svecova, B.; Cajzl, J.; Mackova, A.; Malinsky, P.; Oswald, J.; Kolistsch, A.; Spirkova, J.

    2012-02-01

    Single crystals like lithium niobate are frequently doped with optically active rare-earth or transition-metal ions for a variety of applications in optical devices such as solid-state lasers, amplifiers or sensors. To exploit the potential of the Er:LiNbO 3, one must ensure high intensity of the 1.5 μm luminescence as an inevitable prerequisite. One of the important factors influencing the luminescence properties of a lasing ion is the crystal field of the surrounding, which is inevitably determined by the crystal structure of the pertinent material. From that point it is clear that it cannot be easy to affect the resulting luminescence properties - intensity or position of the luminescence band - without changing the structure of the substrate. However, there is a possibility to utilise a potential of the ion implantation of the lasing ions, optionally accompanied with a sensitising one, that can, besides the doping, also modify the structure of the treated area od the crystal. This effect can be eventually enhanced by a post-implantation annealing that may help to recover the damaged structure and hence to improve the desired luminescence. In this paper we are going to report on our experiments with ion-implantation technique followed with subsequent annealing could be a useful way to influence the crystal field of LN. Optically active Er:LiNbO 3 layers were fabricated by medium energy implantation under various experimental conditions. The Er + ions were implanted at energies of 330 and 500 keV with fluences ranging from 1.0 × 10 15 to 1.0 × 10 16 ion cm -2 into LiNbO 3 single-crystal cuts of both common and special orientations. The as-implanted samples were annealed in air and oxygen at two different temperatures (350 and 600 °C) for 5 h. The depth concentration profiles of the implanted erbium were measured by Rutherford Backscattering Spectroscopy (RBS) using 2 MeV He + ions. The photoluminescence spectra of the samples were measured to determine the

  18. 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.

  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. 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.

  1. Isotopic fractionation in low-energy ion implantation

    NASA Astrophysics Data System (ADS)

    Ponganis, K. V.; Graf, T.; Marti, K.

    1997-08-01

    The evolutions of planetary atmospheres and other solar system reservoirs have been affected by a variety of fractionating mechanisms. It has been suggested that one of these mechanisms could be low-energy ion implantation. Bernatowicz and Hagee [1987] showed that Kr and Xe implanted at low energy onto tungsten are fractionated by approximately 1% per amu, favoring the heavy isotopes; we confirm these effects. We have extended these studies to Ar and Ne, using a modified Bayard-Alpert type implanter design of cylindrical symmetry with collector potentials of -40 to -100V, and observe systematically larger mass dependent isotopic fractionation for argon and neon, >=3% per amu and >=4% per amu, respectively. These fractionations scale approximately as Δm/m for all of the noble gases measured, consistent with the findings of Bernatowicz and coworkers. Experimental data at higher energies and predictions by TRIM (Transport of Ions in Matter) code simulations indicate that sticking probabilities may depend upon the mass ratios of projectile and target. Many natural environments for low-energy ion implantation existed in the early solar nebula, such as in dusty plasmas or in the interaction of the bipolar outflow with small grains or in the wind of the early active Sun with accreting planetesimals. Low-energy ions provide viable sources for gas loading onto nebular dust grains; the result is isotopic and elemental fractionation of the projectiles.

  2. 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.

  3. 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.

  4. 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.

  5. The effects of swift heavy-ion irradiation on helium-ion-implanted silicon

    NASA Astrophysics Data System (ADS)

    Li, B. S.; Du, Y. Y.; Wang, Z. G.; Shen, T. L.; Li, Y. F.; Yao, C. F.; Sun, J. R.; Cui, M. H.; Wei, K. F.; Zhang, H. P.; Shen, Y. B.; Zhu, Y. B.; Pang, L. L.

    2014-10-01

    Cross-sectional transmission electron microscopy (XTEM) was used to study the effects of irradiation with swift heavy ions on helium-implanted silicon. <1 0 0>-oriented silicon wafers were implanted with 30 keV helium to a dose of 3 × 1016 He+/cm2 at 600 K. Subsequently, the helium-implanted Si wafers were irradiated with 792 MeV argon ions. The He bubbles and extended defects in the wafers were examined via XTEM analysis. The results reveal that the mean diameter of the He bubbles increases upon Ar-ion irradiation, while the number density of the He bubbles decreases. The microstructure of the He bubbles observed after Ar-ion irradiation is comparable to that observed after annealing at 1073 K for 30 min. Similarly, the mean size of the extended defects, i.e., Frank loops, increases after Ar-ion irradiation. Possible mechanisms are discussed.

  6. Resonance ionization of holmium for ion implantation in microcalorimeters

    NASA Astrophysics Data System (ADS)

    Schneider, F.; Chrysalidis, K.; Dorrer, H.; Düllmann, Ch. E.; Eberhardt, K.; Haas, R.; Kieck, T.; Mokry, C.; Naubereit, P.; Schmidt, S.; Wendt, K.

    2016-06-01

    The determination of the electron neutrino mass by calorimetric measurement of the 163 Ho electron capture spectrum requires ultra-pure samples. Several collaborations, like ECHo or HOLMES, intend to employ microcalorimeters into which 163 Ho is implanted as an ion beam. This makes a selective and additionally very efficient ion source for holmium mandatory. For this purpose, laser resonance ionization of stable holmium 165 Ho was studied, using a three step excitation scheme driven by pulsed Ti:sapphire lasers. Five measurements with sample sizes of 1014 and 1015 atoms were performed for the efficiency investigation. In average, an excellent ionization efficiency of 32(5) % could be shown, demonstrating the suitability for ion beam implantation.

  7. Photographic-image storage in ion-implanted PLZT ceramics

    SciTech Connect

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

    1982-01-01

    Photographic images can be stored in transparent lead lanthanum zirconate titanate (PLZT) ceramics using near-UV light with photon energies near the band gap energy of 3.42 eV. Coimplanting inert ions, e.g., Ar, Ne and He, into the surface exposed to image light can increase near-UV photosensitivity by a factor of almost 10/sup 4/, with no degradation of image quality, so that the exposure energy threshold is reduced from approx. 100 mJ/cm/sup 2/ to approx. 10 ..mu..Jcm/sup 2/. Coimplanting chemically active and inert ions, e.g., Al or Cr and Ne, can result in similar improvement of the extrinsic (visible light) photosensitivity and in an essentially flat photoresponse from about 400 to 600 nm. In addition, thermal diffusion of Al followed by Ne implantation yield photosensitivity increases in the near-UV comparable to the best results obtained to date with ion implantation.

  8. 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.

  9. 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.

  10. 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

  11. Microwave annealing of ion implanted 6H-SiC

    SciTech Connect

    Gardner, J.A.; Rao, M.V.; Tian, Y.L.; Holland, O.W.; Kelner, G.; Freitas, J.A. Jr.; Ahmad, I.

    1996-12-31

    Microwave rapid thermal annealing has been utilized to remove the lattice damage caused by nitrogen(N) ion-implantation as well as to activate the dopant in 6H-SiC. Samples were annealed at temperatures as high as 1,400 C, for 10 min. Van der Pauw Hall measurements indicate an implant activation of 36%, which is similar to the value obtained for the conventional furnace annealing at 1,600 C. Good lattice quality restoration was observed in the Rutherford backscattering and photoluminescence spectra.

  12. Microwave annealing of ion implanted 6H-SiC

    SciTech Connect

    Gardner, J.A.; Rao, M.V.; Tian, Y.L.; Holland, O.W.; Kelner, G.; Freitas, J.A. Jr.; Ahmad, I.

    1996-05-01

    Microwave rapid thermal annealing has been utilized to remove the lattice damage caused by nitrogen (N) ion-implantation as well as to activate the dopant in 6H-SiC. Samples were annealed at temperatures as high as 1,400 C, for 10 min. Van der Pauw Hall measurements indicate an implant activation of 36%, which is similar to the value obtained for the conventional furnace annealing at 1,600 C. Good lattice quality restoration was observed in the Rutherford backscattering and photoluminescence spectra.

  13. Engineering single photon emitters by ion implantation in diamond.

    PubMed

    Naydenov, B; Kolesov, R; Batalov, A; Meijer, J; Pezzagna, S; Rogalla, D; Jelezko, F; Wrachtrup, J

    2009-11-01

    Diamond provides unique technological platform for quantum technologies including quantum computing and communication. Controlled fabrication of optically active defects is a key element for such quantum toolkit. Here we report the production of single color centers emitting in the blue spectral region by high energy implantation of carbon ions. We demonstrate that single implanted defects show sub-poissonian statistics of the emitted photons and can be explored as single photon source in quantum cryptography. Strong zero phonon line at 470.5 nm allows unambiguous identification of this defect as interstitial-related TR12 color center. PMID:19956415

  14. Ion implantation and diamond-like coatings of aluminum alloys

    SciTech Connect

    Malaczynski, G.W.; Hamdi, A.H.; Elmoursi, A.A.; Qiu, X.

    1997-04-01

    In an attempt to increase the wear resistance of some key automotive components, General Motors Research and Development Center initiated a study to determine the potential of surface modification as a means of improving the tribological properties of automotive parts, and to investigate the feasibility of mass producing such parts. This paper describes the plasma immersion ion implantation system that was designed for the study of various options for surface treatment, and it discusses bench testing procedures used for evaluating the surface-treated samples. In particular, both tribological and microstructural analyses are discussed for nitrogen implants and diamond-like hydrocarbon coatings of some aluminum alloys.

  15. 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) PMID:3776837

  16. Rapid thermal process-induced recombination centers in ion implanted silicon

    NASA Astrophysics Data System (ADS)

    Eichhammer, W.; Hage-Ali, M.; Stuck, R.; Siffert, P.

    1990-04-01

    This work presents direct evidence for a correlation between rapid thermal process-induced recombination centers and co-implanted metallic impurities in ion implanted silicon. Experimental evidence includes the dose dependence of the minority carrier diffusion length measured by the SPV technique, SIMS and RBS analysis of high-dose implantations which show the presence of heavy metals, the dependence of the final diffusion lengths on the mass of the implanted ions, as well as the successful modification of an implantation equipment.

  17. Photovoltage improvements in Cz–Si by low-energy implantation of carbon ions

    NASA Astrophysics Data System (ADS)

    Nadtochiy, A.; Korotchenkov, O.; Romanyuk, B.; Melnik, V.; Popov, V.

    2016-05-01

    We demonstrate photovoltage improvements in Czochralski-grown silicon wafers by low-energy implantation of carbon ions. After annealing at temperatures above ≈550 °C the surface photovoltage (SPV) increases in both implanted and unimplanted sample sets. The increase in the SPV signal observed in implanted samples, which are subsequently annealed at 650 °C and 750 °C, is roughly two times greater than the appropriate values observed in unimplanted wafers. The effect in implanted samples is accompanied by longer time decays in the SPV transients (roughly from several to hundreds of microseconds). In marked contrast, unimplanted samples do not show such a significant difference in the decay times upon annealing. The decay times are fairly evenly distributed across the surface of the implanted but unannealed wafer, whereas the surface distribution function is essentially non-uniform in annealed samples. The results are discussed in terms of the temperature specific defect chemistry. The results of this work open new possibilities for studying defect rearrangement and clustering of atoms in implanted Si and advancing the development of silicon based photovoltaic materials with high photovoltage response. Supplementary data are available from stacks.iop.org/SST/.

  18. Effects of ion-implanted C on the microstructure and surface mechanical properties of Fe alloys implanted with Ti

    NASA Astrophysics Data System (ADS)

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

    1984-09-01

    The microstructural and tribological effects of ion implanting C into Ti-implanted, Fe-based alloys are examined and compared to the influence of C introduced by vacuum carburization during Ti implantation alone. The amorphous surface alloy formed by Ti implantation of pure Fe increases in thickness when additional C is implanted at depths containing Ti but beyond the range of carburization. Pin-on-disc tests of 15-5 PH stainless steel show that implantation of both Ti and C reduces friction significantly under conditions where no reduction is obtained by Ti implantation alone; wear depths are also less when C is implanted. All available experimental results can be accounted for by consideration of the thickness and Ti concentration of the amorphous Fe-Ti-C alloy. The thicker amorphous layer on samples implanted with additional C extends tribological benefits to more severe wear regimes.

  19. 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.

  20. Charging mechanism during ion implantation without charge compensation

    NASA Astrophysics Data System (ADS)

    Sakai, Shigeki; Fan, Hung-chi; Chen, Emily; Tanjyo, Masayasu

    2006-11-01

    The charge accumulated on an electrode electrically floated during implantation is calculated using a simple model. The model includes the ion beam current, the secondary electron emission, the neutralizing electron current and the leak current through resistance between the electrode and the bulk of wafer. Expressing the leak current with a parameter of relaxation time, it is found that amount of the accumulated charge at the completion of implantation reached at a constant irrespective of the beam current in the condition that the relaxation time is long enough. The experimental result showed that the measured potential of the floated electrode depends on a beam potential as well as the beam current. This result implies that the neutralizing electrons are more effectively transported to the isolated electrode in the high beam current condition compared with in the low beam current condition. We discuss possibility that such charging phenomena may occur in the implantation for BiCMOS or SOI device fabrication.

  1. 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.

  2. First tests of the ion irradiation and implantation beamline at the CMAM

    NASA Astrophysics Data System (ADS)

    Jiménez-Rey, D.; Benedicto, M.; Muñoz-Martín, A.; Bachiller-Perea, D.; Olivares, J.; Climent-Font, A.; Gómez-Ferrer, B.; Rodríguez, A.; Narros, J.; Maira, A.; Álvarez, J.; Nakbi, A.; Zucchiatti, A.; de Aragón, F.; García, J. M.; Vila, R.

    2014-07-01

    The implantation and irradiation beamline of the Tandem ion accelerator of the Centro de Micro Análisis de Materiales (CMAM), in Madrid, has been recently completed with a beam sweep and monitoring system, and a cryostat/furnace. These new implementations convert the beamline into a versatile tool to implant ions, between H and Au2, in different materials with precise control of the sample temperature, which may be varied between -180 °C and 600 °C. The size of the swept area on target may be as large as 10 × 10 cm2. The implantation chamber also allows carrying out in situ or/and on line analyses during the irradiations by means of advanced optical measurements, as well as ion beam analyses (IBA). These advancements can be employed in novel applications such as the fabrication of optical waveguides and irradiation tests of structural and functional materials for future fusion reactors. The results of beam tests and first experiments are shown.

  3. Upgraded vacuum arc ion source for metal ion implantation

    SciTech Connect

    Nikolaev, A. G.; Oks, E. M.; Savkin, K. P.; Yushkov, G. Yu.; Brown, I. G.

    2012-02-15

    Vacuum arc ion sources have been made and used by a large number of research groups around the world over the past twenty years. The first generation of vacuum arc ion sources (dubbed ''Mevva,'' for metal vapor vacuum arc) was developed at Lawrence Berkeley National Laboratory in the 1980s. This paper considers the design, performance parameters, and some applications of a new modified version of this kind of source which we have called Mevva-V.Ru. The source produces broad beams of metal ions at an extraction voltage of up to 60 kV and a time-averaged ion beam current in the milliampere range. Here, we describe the Mevva-V.Ru vacuum arc ion source that we have developed at Tomsk and summarize its beam characteristics along with some of the applications to which we have put it. We also describe the source performance using compound cathodes.

  4. 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.

  5. 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.

  6. Temperature behavior of damage in sapphire implanted with light ions

    NASA Astrophysics Data System (ADS)

    Alves, E.; Marques, C.; Sáfrán, G.; McHargue, Carl J.

    2009-05-01

    In this study, we compare and discuss the defect behavior of sapphire single crystals implanted with different fluences (1 × 1016-1 × 1017 cm-2) of carbon and nitrogen with 150 keV. The implantation temperatures were RT, 500 °C and 1000 °C to study the influence of temperature on the defect structures. For all the ions the Rutherford backscattering-channeling (RBS-C) results indicate a surface region with low residual disorder in the Al-sublattice. Near the end of range the channeled spectrum almost reaches the random indicating a high damage level for fluences of 1 × 1017 cm-2. The transmission electron microscopy (TEM) photographs show a layered contrast feature for the C implanted sample where a buried amorphous region is present. For the N implanted sample the Electron Energy Loss Spectroscopy (EELS) elemental mapping give evidence for the presence of a buried damage layer decorated with bubbles. Samples implanted at high temperatures (500 °C and 1000 °C) show a strong contrast fluctuation indicating a defective crystalline structure of sapphire.

  7. Oxidation of ion-implanted NiAl

    SciTech Connect

    Hanrahan, R.J. Jr.; Verink, E.D. Jr.; Withrow, S.P.

    1994-12-31

    The oxidation of NiAl is complicated by the formation of transient alumina phases which result in convoluted scales which are prone to spallation. We have investigated high-dose implantation of oxygen as a technique for forming a protective oxide layer on the surface of NiAl and thereby bypassing the conditions that lead to transient oxide formation. Single crystal specimens of high purity NiAl were implanted with 1 {times} 10{sup 18} {sup 18}O ions/cm{sup 2} at 160 keV. Implanted specimens were annealed for times ranging from 5 to 60 minutes in a reducing atmosphere. Oxidation experiments were conducted for periods ranging from 1 hour to 42 hours under both cyclic and isothermal conditions. Specimens in the as-implanted, annealed, and oxidized conditions were examined using Auger electron microscopy. Oxygen implantation followed by annealing was found to form an epitaxial oxide layer. This layer is stable for the duration of the oxidation experiments conducted in this study, and was found to result in reduced oxidation and improved resistance to scale spallation.

  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. 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.

  10. Indium Phosphide Nanocrystals Formed in Silica by Sequential Ion Implantation

    SciTech Connect

    Denmark, D.; Ueda, A.; Shao, C. L.; Wu, M. H.; Mu, R.; White, Clark W; Vlahovic, B.; Muntele, C. I.; Ila, Dr. Daryush; Liu, Y. C.

    2005-01-01

    Fused silica substrates were implanted with: (1) phosphorus only, (2) indium only, and (3) phosphorus plus indium ions. Vibrational and electronic characterizations have been performed on the P only and In only samples to obtain an understanding of the thermal annealing behavior in order to obtain a meaningful guide for the fabrication of InP quantum dots (QDs) formed by sequential ion implantation of In and P in SiO{sub 2}. Thermal annealing procedures for InP synthesis have been established and InP quantum dots are confirmed by TEM, XRD and far infrared measurements. Far IR spectra show a single resonance at 323 cm{sup -1} rather than two absorption peaks in its counterpart of bulk InP crystals. The single band absorption is attributed to the surface phonon of InP quantum dots which will appear between transverse optical (TO) and longitudinal optical (LO) phonon modes of the bulk.

  11. Thermal stability of ion-implanted ZnO

    SciTech Connect

    Coleman, V; Tan, H; Jagadish, C; Kucheyev, S; Zou, J

    2005-06-16

    Zinc oxide single crystals implanted at room temperature with high-dose (1.4 x 10{sup 17} cm{sup -2}) 300 keV As{sup +} ions are annealed at 1000-1200 C. Damage recovery is studied by a combination of Rutherford backscattering/ channeling spectrometry (RBS/C), cross-sectional transmission electron microscopy (XTEM), and atomic force microscopy (AFM). Results show that such a thermal treatment leads to the decomposition and evaporation of the heavily-damaged layer instead of apparent defect recovery and recrystallization that could be inferred from RBS/C and XTEM data alone. Such a relatively poor thermal stability of heavily-damaged ZnO has significant implications for understanding results on thermal annealing of ion-implanted ZnO.

  12. FIM/IAP/TEM studies of ion implanted nickel emitters

    SciTech Connect

    Walck, S.D.; Hren, J.J.

    1985-01-01

    Accurate depth profiling of implanted hydrogen and its isotopes in metals is extremely important. Field ion microscopy and atom-probe techniques provide the most accurate depth profiling analytical method of any available. In addition, they are extremely sensitive to hydrogen. This paper reports our early work on hydrogen trapping at defects in metals using the Field Ion Microscope/Imaging Atom Probe (FIM/IAP). Our results deal primarily with the control experiments required to overcome instrumental difficulties associated with in situ implantation and the influence of a high electric field. Transmission Electron Microscopy (TEM) has been used extensively to independently examine the influence of high electric fields on emitters. 11 references, 7 figures.

  13. Tribological properties changes of H13 steel induced by MEVVA Ta ion implantation*1

    NASA Astrophysics Data System (ADS)

    Jianhua, Yang; Tonghe, Zhang

    2004-05-01

    The tribological properties of Ta-implanted H13 steel was studied using a metal vapor vacuum arc (MEVVA) ion source. The doses of Ta and C ions implanted on H13 steel were 5×10 17 and 2×10 17 cm -2, respectively. The extraction voltages were 48 kV for Ta implantation and 30 kV for C implantation. Rutherford backscattering spectrum (RBS) was used to measure the surface composition of the samples implanted. The observation of phase induced by Ta, C implantation was carried out by grazing-angle X-ray diffraction (GXRD). The wear test of the implanted surface revealed that Ta+C dual implantation reduced the wear of the implanted steel by nearly a factor of 2. This wear mechanism of the Ta-implanted steel was compared with that of Ti implantation.

  14. Urinary catheter with polyurethane coating modified by ion implantation

    NASA Astrophysics Data System (ADS)

    Kondyurina, I.; Nechitailo, G. S.; Svistkov, A. L.; Kondyurin, A.; Bilek, M.

    2015-01-01

    A low friction urinary catheter that could be used without a lubricant is proposed in this work. A polyurethane coating was synthesised on the surface of a metal guide wire catheter. Ion implantation was applied to surface modify the polyurethane coating. FTIR ATR, wetting angle, AFM and friction tests were used for analysis. Low friction was found to be provided by the formation of a hard carbonised layer on the polyurethane surface.

  15. 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.

  16. 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

  17. Ca and O ion implantation doping of GaN

    SciTech Connect

    Zolper, J.C.; Wilson, R.G.; Pearton, S.J.; Stall, R.A.

    1996-04-01

    {ital p}- and {ital n}-type doping of GaN have been realized by ion implantation of Ca and O, respectively. Rapid thermal annealing at 1100{degree}C or higher is required to achieve {ital p}-type conduction in Ca or Ca+P implanted samples with an estimated ionization level of 169 meV and a corresponding activation efficiency of {approximately}100{percent}. This is the first experimental report of an acceptor species in GaN, other than Mg, with an ionization energy level less than 180 meV. O-implanted GaN displays an ionization level of {approximately}29 meV but with an activation efficiency of only 3.6{percent} after a 1050{degree}C anneal that may result from insufficient vacancy generation for the lighter O ion or from the existence of a second, deeper O energy level. Neither Ca or O displayed measurable redistribution, based on secondary ion mass spectrometry measurements, even after a 1125{degree}C anneal. {copyright} {ital 1996 American Institute of Physics.}

  18. Observations of Ag diffusion in ion implanted SiC

    DOE PAGESBeta

    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,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

  19. Ablation Plasma Ion Implantation Optimization and Deposition of Compound Coatings

    NASA Astrophysics Data System (ADS)

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

    2002-10-01

    Ablation Plasma Ion Implantation (APII) utilizes KrF laser ablation plasma plumes to implant ions into pulsed, negatively-biased substrates [1]. Ablation targets are Ti foils and TiN disks. Substrates are Si wafers and Al, biased from 0 to -10 kV. Optimization experiments address: 1) configurations that reduce arcing, 2) reduction of particulate, and 3) deposition/implantation of compounds (e.g. TiN). Arcing is suppressed by positioning the target perpendicular (previously parallel) to the substrate. Thus, bias voltage can be applied at the same time as the KrF laser, resulting in higher ion current. This geometry also yields lower particulate. APII with TiN has the goal of hardened coatings with excellent adhesion. SEM, AFM, XPS, TEM, and scratch tests characterize properties of the thin films. Ti APII films at - 4kV are smoother with lower friction. 1. B. Qi, R.M. Gilgenbach, Y.Y. Lau, M.D. Johnston, J. Lian, L.M. Wang, G. L. Doll and A. Lazarides, APL, 78, 3785 (2001) * Research funded by NSF

  20. 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.

  1. 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.

  2. Ion beam analysis of aluminium ion implanted titanium diboride thin films

    NASA Astrophysics Data System (ADS)

    Mollica, S.; Sood, D. K.; Evans, P. J.; Dytlewski, N.; Short, K. T.

    2002-05-01

    Titanium diboride is often selected for protective coatings due to its high hardness and wear resistance. However, its possible high temperature applications are limited because it exhibits poor oxidation resistance at elevated temperatures. Through ion beam modification, it was anticipated that a stable oxidation barrier could form via the formation of "metastable phases" not otherwise observed in stoichiometric TiB 2. Titanium diboride films were deposited onto single-crystal Si(1 0 0) substrates using DC magnetron sputtering. MEVVA ion implantation was then performed using an extraction voltage of 40 kV. Selected samples were subjected to post-implantation vacuum annealing prior to oxidation, thus comparing the behaviour of crystalline and amorphous films. Results show that aluminium ion implantation reduces the oxidation rate of DC magnetron sputtered titanium diboride thin films within the experimental temperature range.

  3. A comparative study of the structure and cytotoxicity of polytetrafluoroethylene after ion etching and ion implantation

    NASA Astrophysics Data System (ADS)

    Shtansky, D. V.; Glushankova, N. A.; Kiryukhantsev-Korneev, F. V.; Sheveiko, A. N.; Sigarev, A. A.

    2011-03-01

    The ion-plasma treatment has been widely used for modifying the surface structure of polymers in order to improve their properties, but it can lead to destruction of the surface and, as a consequence, to an increase in their toxicity. A comparative study of the structure and cytotoxicity of polytetrafluoroethylene (PTFE) after the ion etching (IE) and ion implantation (II) for 10 min with energy densities of 363 and 226 J/cm2, respectively, has been performed. It has been shown that, unlike the ion implantation, the ion etching results in the destruction of the polymer and in the appearance of the cytotoxicity. The factors responsible for this effect, which are associated with the bulk and surface treatment, as well as with the influence of the temperature, have been discussed.

  4. Experimental results of a dual-beam ion source for 200 keV ion implanter

    SciTech Connect

    Chen, L. H. Cui, B. Q.; Ma, R. G.; Ma, Y. J.; Tang, B.; Huang, Q. H.; Jiang, W. S.; Zheng, Y. N.

    2014-02-15

    A dual beam ion source for 200 keV ion implanter aimed to produce 200 keV H{sub 2}{sup +} and He{sup +} beams simultaneously has been developed. Not suitable to use the analyzing magnet, the purity of beam extracted from the source becomes important to the performance of implanter. The performance of ion source was measured. The results of experiments show that the materials of inlet tube of ion source, the time of arc ionization in ion source, and the amount of gas flow have significant influence on the purity of beam. The measures by using copper as inlet tube material, long time of arc ionization, and increasing the inlet of gas flow could effectively reduce the impurity of beam. And the method using the gas mass flow controller to adjust the proportion of H{sub 2}{sup +} and He{sup +} is feasible.

  5. 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.

  6. 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.

  7. The two faces of metal ions: From implants rejection to tissue repair/regeneration.

    PubMed

    Vasconcelos, Daniel M; Santos, Susana G; Lamghari, Meriem; Barbosa, Mário A

    2016-04-01

    The paradigm of metallic ions as exclusive toxic agents is changing. During the last 60 years, knowledge about toxicological and immunological reactions to metal particles and ions has advanced considerably. Hip prostheses, namely metal-on-metal bearings, have prompted studies about excessive and prolonged exposure to prosthetic debris. In that context, the interactions of metal particles and ions with cells and tissues are mostly harmful, inducing immune responses that lead to osteolysis and implant failure. However, in the last decade, new strategies to promote immunomodulation and healing have emerged based on the unique properties of metallic ions. The atom-size and charge enable ions to interact with key macromolecules (e.g. proteins, nucleic acids) that affect cellular function. Moreover, these agents are inexpensive, stable and can be integrated in biomaterials, which may open new avenues for a novel generation of medical devices. Herein, orthopedic devices are discussed as models for adverse responses to metal ions, and debated together with the potential to use metal ions-based therapies, thus bridging the gap between unmet clinical needs and cutting-edge research. In summary, this review addresses the two "faces" of metallic ions, from pathological responses to innovative research strategies that use metal ions for regenerative medicine. PMID:26851391

  8. Fabrication of porous TiO2 nanorod array photoelectrodes with enhanced photoelectrochemical water splitting by helium ion implantation.

    PubMed

    Liu, Yichao; Shen, Shaohua; Ren, Feng; Chen, Jianan; Fu, Yanming; Zheng, Xudong; Cai, Guangxu; Xing, Zhuo; Wu, Hengyi; Jiang, Changzhong

    2016-05-19

    Porous photoelectrodes show high efficiency in hydrogen production by water splitting. However, fabrication of porous nanorods is usually difficult. Here, we report a simple approach to fabricate a kind of novel porous rutile titanium dioxide nanorod array by an advanced ion implantation method using multiple-energy helium ion implantation and subsequent annealing. The porous nanostructure enhances the photoelectrochemical performance of the titanium dioxide nanorod array photoelectrodes under Uv-visible light illumination, where the highest photocurrent density was relatively about 10 times higher than that of the pristine titanium dioxide nanorod array. The formation of nanocavities mainly contributes to the enhancement of the photocurrent density by trapping holes inside to separate the charge carriers. The study demonstrates that ion implantation could be an effective approach to develop novel porous nanostructural photoelectrodes for the application of hydrogen production. PMID:27145900

  9. 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.

  10. 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.

  11. 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.

  12. Defect studies of zirconia implanted by high energy Xe ions

    NASA Astrophysics Data System (ADS)

    Melikhova, O.; Čížek, J.; Procházka, I.; Hruška, P.; Skuratov, V. A.; Konstantinova, T. E.; Danilenko, I. A.

    2016-01-01

    In the present work positron lifetime spectroscopy was employed for characterization of radiation-induced defects in yttria stabilized zirconia (YSZ) implanted by 167 MeV Xe ions. Positron lifetime data were interpreted with aid of ab-initio theoretical modelling of defects in YSZ lattice. Damage caused by Xe implantation was investigated in two YSZ samples with different microstructure: (i) single crystal and (ii) sintered ceramic. The virgin YSZ single crystal exhibits single component spectrum with lifetime of ≈ 180 ps. Similar lifetime component was found also in the virgin sample of sintered YSZ ceramic. Since this lifetime is significantly higher than the YSZ bulk lifetime the virgin YSZ crystal and the sintered ceramic both contain vacancy-like defects. Xe implantation leads to appearance of additional defect component with longer lifetime ≈ 370 ps which comes obviously from vacancy clusters fonned by agglomeration of irradiation induced vacancies. A broad absorption band with peak absorption at ≈ 518 nm was found in Xe-implanted crystal by optical measurements.

  13. 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.

  14. Formation of vanadium silicide by high dose ion implantation

    NASA Astrophysics Data System (ADS)

    Salvi, V. P.; Narsale, A. M.; Vidwans, S. V.; Rangwala, A. A.; Guzman, L.; Dapor, M.; Giunta, G.; Calliari, L.; Marchetti, F.

    1987-10-01

    The vanadium silicide system has been found to be of increasing interest because one of the silicide phases viz. V 3Si with the A-15 structure is often accompanied by a high temperature superconductivity. We have studied the formation of vanadium silicide layers by high dose ion implantation. 30 keV 51V + ions were implanted at room temperature onto thermally evaporated a-Si films on thermally grown SiO 2 substrates. The samples were annealed in vacuum to study the possible evolution of V-Si phases. Both Seeman-Bohlin X-ray diffraction and Auger/sputter profiling techniques were used to analyse these samples. The observed Auger depth profile of the annealed samples shows a more uniform vanadium distribution as compared to the vanadium distribution in as-implanted samples, along with the changes in the Si L 2,3VV lineshape. The X-ray diffraction results show the formation of V 3Si, V 5Si 3 and VSi 2 phases. After annealing the sample in vacuum, a more ordered growth of V 3Si phase is found to be accompanied by an increase in VSi 2 phase. This has been related to the possible changes ocurring in the a-Si layers due to annealing of the sample.

  15. High- Tc superconductor characteristics control by ion implantation

    NASA Astrophysics Data System (ADS)

    Matsui, S.; Matsutera, H.; Yoshitake, T.; Fujita, J.; Satoh, T.

    1989-03-01

    Transition temperature ( Tc) control and annealing effects of YBa 2Cu 3O x and Bi 2Sr 1.4 Ca 1.8Cu 2.2O y superconductor thin films implanted by 200 keV Ne + have been investigated. YBa 2Cu 3 O xTc end points for 0, 1 × 10 14, 1 × 10 15 and 1 × 10 16 ions/cm 2 doses are 75, 71, 62 and 16 K, respectively. On the other hand, Bi 2Sr 1.4Ca 1.8Cu 2.2O y, Tc end points for 0, 1 × 10 12 and 1 × 10 13 ions/cm 2 doses are 78, 76 and 54 K, respectively, c lattice constant increases were observed for the implanted films. It is confirmed that the superconducting characteristics for films, are recovered by anneaing in O 2 atomosphere. Moreover, microcrystal growth caused by annealing the implanted YBa 2Cu 3O x film was observed on the surface.

  16. Integration of Ion Implantation with Scanning ProbeAlignment

    SciTech Connect

    Persaud, A.; Rangelow, I.W.; Schenkel, T.

    2005-03-01

    We describe a scanning probe instrument which integrates ion beams with imaging and alignment functions of a piezo resistive scanning probe in high vacuum. Energetic ions (1 to a few hundred keV) are transported through holes in scanning probe tips [1]. Holes and imaging tips are formed by Focused Ion Beam (FIB) drilling and ion beam assisted thin film deposition. Transport of single ions can be monitored through detection of secondary electrons from highly charged dopant ions (e. g., Bi{sup 45+}) enabling single atom device formation. Fig. 1 shows SEM images of a scanning probe tip formed by ion beam assisted Pt deposition in a dual beam FIB. Ion beam collimating apertures are drilled through the silicon cantilever with a thickness of 5 {micro}m. Aspect ratio limitations preclude the direct drilling of holes with diameters well below 1 {micro}m, and smaller hole diameters are achieved through local thin film deposition [2]. The hole in Fig. 1 was reduced from 2 {micro}m to a residual opening of about 300 nm. Fig. 2 shows an in situ scanning probe image of an alignment dot pattern taken with the tip from Fig. 1. Transport of energetic ions through the aperture in the scanning probe tip allows formation of arbitrary implant patterns. In the example shown in Fig. 2 (right), a 30 nm thick PMMA resist layer on silicon was exposed to 7 keV Ar{sup 2+} ions with an equivalent dose of 10{sup 14} ions/cm{sup 2} to form the LBL logo. An exciting goal of this approach is the placement of single dopant ions into precise locations for integration of single atom devices, such as donor spin based quantum computers [3, 4]. In Fig. 3, we show a section of a micron size dot area exposed to a low dose (10{sup 11}/cm{sup 2}) of high charge state dopant ions. The Bi{sup 45+} ions (200 keV) were extracted from a low emittance highly charged ions source [5]. The potential energy of B{sup 45+}, i. e., the sum of the binding energies required to remove the electrons, amounts to 36 ke

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

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

  18. Fabrication of porous TiO2 nanorod array photoelectrodes with enhanced photoelectrochemical water splitting by helium ion implantation

    NASA Astrophysics Data System (ADS)

    Liu, Yichao; Shen, Shaohua; Ren, Feng; Chen, Jianan; Fu, Yanming; Zheng, Xudong; Cai, Guangxu; Xing, Zhuo; Wu, Hengyi; Jiang, Changzhong

    2016-05-01

    Porous photoelectrodes show high efficiency in hydrogen production by water splitting. However, fabrication of porous nanorods is usually difficult. Here, we report a simple approach to fabricate a kind of novel porous rutile titanium dioxide nanorod array by an advanced ion implantation method using multiple-energy helium ion implantation and subsequent annealing. The porous nanostructure enhances the photoelectrochemical performance of the titanium dioxide nanorod array photoelectrodes under Uv-visible light illumination, where the highest photocurrent density was relatively about 10 times higher than that of the pristine titanium dioxide nanorod array. The formation of nanocavities mainly contributes to the enhancement of the photocurrent density by trapping holes inside to separate the charge carriers. The study demonstrates that ion implantation could be an effective approach to develop novel porous nanostructural photoelectrodes for the application of hydrogen production.Porous photoelectrodes show high efficiency in hydrogen production by water splitting. However, fabrication of porous nanorods is usually difficult. Here, we report a simple approach to fabricate a kind of novel porous rutile titanium dioxide nanorod array by an advanced ion implantation method using multiple-energy helium ion implantation and subsequent annealing. The porous nanostructure enhances the photoelectrochemical performance of the titanium dioxide nanorod array photoelectrodes under Uv-visible light illumination, where the highest photocurrent density was relatively about 10 times higher than that of the pristine titanium dioxide nanorod array. The formation of nanocavities mainly contributes to the enhancement of the photocurrent density by trapping holes inside to separate the charge carriers. The study demonstrates that ion implantation could be an effective approach to develop novel porous nanostructural photoelectrodes for the application of hydrogen production. Electronic

  19. 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.

  20. 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.

  1. Ion implantation induced modification of structural and magnetic properties of perpendicular media

    NASA Astrophysics Data System (ADS)

    Gaur, Nikita; Piramanayagam, S. N.; Maurer, S. L.; Nunes, R. W.; Steen, S.; Yang, H.; Bhatia, C. S.

    2011-09-01

    This study reports the effects of implanting various doses of boron (11B+) and argon (40Ar+) ions into the recording layer and the soft underlayer of CoCrPt-SiO2-based perpendicular recording media. Implantation of a lower dose of boron ions (1011 ions cm-2) in the recording layer was found to reduce the out-of-plane coercivity, whereas no changes in the coercivity were observed when they were implanted into the soft underlayer. In the case of argon ions, lower dose implantation did not show any changes in the coercivity, irrespective of the implanted layer. However, higher dose implantations (1016 ions cm-2) of all the species were found to cause a reduction in coercivity, irrespective of the implanted layer. The reduction in coercivity was more significant when the ions were implanted in the recording layer compared with the case of implantation in the soft underlayer. X-ray diffraction (XRD) results on samples where argon was implanted in the recording layer showed a strong shift in the position of Co (0 0 .2) peaks, indicating an increase in the 'c' parameter. The shift is explained, on the basis of x-ray photoelectron spectroscopy, to be arising from intra-layer mixing at the CoCrPt-SiO2/Ru interface. Magnetic force microscopy images indicated an increase in domain size arising from the ion implantation.

  2. Advances in the surface modification techniques of bone-related implants for last 10 years

    PubMed Central

    Qiu, Zhi-Ye; Chen, Cen; Wang, Xiu-Mei; Lee, In-Seop

    2014-01-01

    At the time of implanting bone-related implants into human body, a variety of biological responses to the material surface occur with respect to surface chemistry and physical state. The commonly used biomaterials (e.g. titanium and its alloy, Co–Cr alloy, stainless steel, polyetheretherketone, ultra-high molecular weight polyethylene and various calcium phosphates) have many drawbacks such as lack of biocompatibility and improper mechanical properties. As surface modification is very promising technology to overcome such problems, a variety of surface modification techniques have been being investigated. This review paper covers recent advances in surface modification techniques of bone-related materials including physicochemical coating, radiation grafting, plasma surface engineering, ion beam processing and surface patterning techniques. The contents are organized with different types of techniques to applicable materials, and typical examples are also described. PMID:26816626

  3. Experimental investigation of plasma-immersion ion implantation treatment for biocompatible polyurethane implants production

    NASA Astrophysics Data System (ADS)

    Iziumov, R. I.; Beliaev, A. Y.; Kondyurina, I. V.; Shardakov, I. N.; Kondyurin, A. V.; Bilek, M. M.; McKenzie, D. R.

    2016-04-01

    Modification of the surface layer of polyurethane with plasma-immersion ion implantation (PIII) and studying its physical and chemical changes have been discussed in this paper. The goal of the research was to obtain carbonized layer allowing creating biocompatible polyurethane implants. The experiments of PIII treatment in various modes were performed. The investigation of the modified surface characteristics was carried out by observing the kinetics of free surface energy for two weeks after treatment. The regularities between treatment time and the level of free surface energy were detected. The explanation of high energy level was given through the appearance of free radicals in the surface layer of material. The confirmation of the chemical activation of the polyurethane surface after PIII treatment was obtained.

  4. GaAs transistors formed by Be or Mg ion implantation

    NASA Technical Reports Server (NTRS)

    Hunsperger, R. G.; Marsh, O. J.

    1974-01-01

    N-p-n transistor structures have been formed in GaAs by implanting n-type substrates with Be ions to form base regions and then implanting them with 20-keV Si ions to form emitters. P-type layers have been produced in GaAs by implantation of either Mg or Be ions, with substrate at room temperature, followed by annealing at higher temperatures.

  5. 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.

  6. TEM characterization of simultaneous triple ion implanted ODS Fe12Cr

    NASA Astrophysics Data System (ADS)

    de Castro, Vanessa; Briceno, Martha; Lozano-Perez, Sergio; Trocellier, Patrick; Roberts, Steve G.; Pareja, Ramiro

    2014-12-01

    Understanding the behavior of oxide dispersion strengthened (ODS) ferritic/martensitic steels under irradiation is vital in the design of advanced fusion reactors. In this work, a simultaneous triple ion implanted ODS Fe12Cr steel was investigated by transmission electron microscopy in order to determine the effect of irradiation on the grain and dislocation structures, oxide nanoparticles and other secondary phases present in the steel. The ODS steel was irradiated at RT with Fe8+, He+ and H+ at the JANNUS-Saclay facility to a damage of 4.4 dpa. Results show that ODS nanoparticles appear very stable under these irradiation conditions.

  7. Dose Control System in the Optima XE Single Wafer High Energy Ion Implanter

    SciTech Connect

    Satoh, Shu; Yoon, Jongyoon; David, Jonathan

    2011-01-07

    Photoresist outgassing can significantly compromise accurate dosimetry of high energy implants. High energy implant even at a modest beam current produces high beam powers which create significantly worse outgassing than low and medium energy implants and the outgassing continues throughout the implant due to the low dose in typical high energy implant recipes. In the previous generation of high energy implanters, dose correction by monitoring of process chamber pressure during photoresist outgassing has been used. However, as applications diversify and requirements change, the need arises for a more versatile photoresist correction system to match the versatility of a single wafer high energy ion implanter. We have successfully developed a new dosimetry system for the Optima XE single wafer high energy ion implanter which does not require any form of compensation due to the implant conditions. This paper describes the principles and performance of this new dose system.

  8. Dose Control System in the Optima XE Single Wafer High Energy Ion Implanter

    NASA Astrophysics Data System (ADS)

    Satoh, Shu; Yoon, Jongyoon; David, Jonathan

    2011-01-01

    Photoresist outgassing can significantly compromise accurate dosimetry of high energy implants. High energy implant even at a modest beam current produces high beam powers which create significantly worse outgassing than low and medium energy implants and the outgassing continues throughout the implant due to the low dose in typical high energy implant recipes. In the previous generation of high energy implanters, dose correction by monitoring of process chamber pressure during photoresist outgassing has been used. However, as applications diversify and requirements change, the need arises for a more versatile photoresist correction system to match the versatility of a single wafer high energy ion implanter. We have successfully developed a new dosimetry system for the Optima XE single wafer high energy ion implanter which does not require any form of compensation due to the implant conditions. This paper describes the principles and performance of this new dose system.

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

    NASA Astrophysics Data System (ADS)

    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.

  10. Model for ion-implantation-induced improvements of photoferroelectric imaging in lead lanthanum zirconate titanate ceramics

    SciTech Connect

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

    1980-11-01

    Studies of photoferroelectric image storage in H-, He-, and, more recently, Ar-implanted /(PLZT) lead lanthanum zirconate titanate reveal that the photosensitivity can be significantly increased by ion implantation into the image storage surface. For example, the photosensitivity after implantation with 5 x 10/sup 14/ 500-keV Ar/cm/sup 2/ is increased by about three orders of magnitude over that of unimplanted PLZT. The increase in photosensitivity results from a decrease in dark conductivity and changes in the photoconductivity of the implanted layer. We present a phenomenological model which describes the photosensitivity enhancement obtained by ion implantation. This model takes into account both light- and ion- implantation-induced changes in conductivity and gives quantitative agreement with the measured changes in the coercive voltage with near-UV light intensity for ion-implantated PLZT.

  11. Structure analysis of bimetallic Co-Au nanoparticles formed by sequential ion implantation

    NASA Astrophysics Data System (ADS)

    Chen, Hua-jian; Wang, Yu-hua; Zhang, Xiao-jian; Song, Shu-peng; chen, Hong; Zhang, Ke; Xiong, Zu-zhao; Ji, Ling-ling; Dai, Hou-mei; Wang, Deng-jing; Lu, Jian-duo; Wang, Ru-wu; Zheng, Li-rong

    2016-08-01

    Co-Au alloy Metallic nanoparticles (MNPs) are formed by sequential ion implantation of Co and Au into silica glass at room temperature. The ion ranges of Au ions implantation process have been displayed to show the ion distribution. We have used the atomic force microscopy (AFM) and transmission electron microscopy (TEM) to investigate the formation of bimetallic nanoparticles. The extended X-ray absorption fine structure (EXAFS) has been used to study the local structural information of bimetallic nanoparticles. With the increase of Au ion implantation, the local environments of Co ions are changed enormously. Hence, three oscillations, respectively, Co-O, Co-Co and Co-Au coordination are determined.

  12. 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.

  13. The ion implantation-induced properties of one-dimensional nanomaterials

    PubMed Central

    2013-01-01

    Nowadays, ion implantation is an extensively used technique for material modification. Using this method, we can tailor the properties of target materials, including morphological, mechanical, electronic, and optical properties. All of these modifications impel nanomaterials to be a more useful application to fabricate more high-performance nanomaterial-based devices. Ion implantation is an accurate and controlled doping method for one-dimensional nanomaterials. In this article, we review recent research on ion implantation-induced effects in one-dimensional nanostructure, such as nanowires, nanotubes, and nanobelts. In addition, the optical property of single cadmium sulfide nanobelt implanted by N+ ions has been researched. PMID:23594476

  14. The ion implantation-induced properties of one-dimensional nanomaterials

    NASA Astrophysics Data System (ADS)

    Li, Wen Qing; Xiao, Xiang Heng; Stepanov, Andrey L.; Dai, Zhi Gao; Wu, Wei; Cai, Guang Xu; Ren, Feng; Jiang, Chang Zhong

    2013-04-01

    Nowadays, ion implantation is an extensively used technique for material modification. Using this method, we can tailor the properties of target materials, including morphological, mechanical, electronic, and optical properties. All of these modifications impel nanomaterials to be a more useful application to fabricate more high-performance nanomaterial-based devices. Ion implantation is an accurate and controlled doping method for one-dimensional nanomaterials. In this article, we review recent research on ion implantation-induced effects in one-dimensional nanostructure, such as nanowires, nanotubes, and nanobelts. In addition, the optical property of single cadmium sulfide nanobelt implanted by N+ ions has been researched.

  15. Pulsed-electron-beam annealing of ion-implantation damage

    NASA Technical Reports Server (NTRS)

    Greenwald, A. C.; Kirkpatrick, A. R.; Little, R. G.; Minnucci, J. A.

    1979-01-01

    Short-duration high-intensity pulsed electron beams have been used to anneal ion-implantation damage in silicon and to electrically activate the dopant species. Lattice regrowth and dopant activation were determined using He(+)-4 backscattering, SEM, TEM, and device performance characteristics as diagnostic techniques. The annealing mechanism is believed to be liquid-phase epitaxial regrowth initiating from the substrate. The high-temperature transient pulse produced by the electron beam causes the dopant to diffuse rapidly in the region where the liquid state is achieved.

  16. Cost estimates for commercial plasma source ion implantation

    SciTech Connect

    Rej, D.J. ); Alexander, R.B. )

    1994-07-01

    A semiempirical model for the cost of a commercial plasma source ion implantation (PSII) facility is presented. Amortized capital and operating expenses are estimated as functions of the surface area throughput [ital T]. The impact of secondary electron emission and batch processing time is considered. Treatment costs are found to decrease monotonically with [ital T] until they saturate at large [ital T] when capital equipment payback and space rental dominate the expense. A reasonably sized PSII treatment facility should be able to treat a surface area of 10[sup 4] m[sup 2] per year at a cost of $0.01 per cm[sup 2].

  17. Magnetic insulation of secondary electrons in plasma source ion implantation

    SciTech Connect

    Rej, D.J.; Wood, B.P.; Faehl, R.J.; Fleischmann, H.H.

    1993-09-01

    The uncontrolled loss of accelerated secondary electrons in plasma source ion implantation (PSII) can significantly reduce system efficiency and poses a potential x-ray hazard. This loss might be reduced by a magnetic field applied near the workpiece. The concept of magnetically-insulated PSII is proposed, in which secondary electrons are trapped to form a virtual cathode layer near the workpiece surface where the local electric field is essentially eliminated. Subsequent electrons that are emitted can then be reabsorbed by the workpiece. Estimates of anomalous electron transport from microinstabilities are made. Insight into the process is gained with multi-dimensional particle-in-cell simulations.

  18. Metal ion implantation in inert polymers for strain gauge applications

    NASA Astrophysics Data System (ADS)

    Di Girolamo, Giovanni; Massaro, Marcello; Piscopiello, Emanuela; Tapfer, Leander

    2010-10-01

    Metal ion implantation in inert polymers may produce ultra-thin conducting films below the polymer surface. These subsurface films are promising structures for strain gauge applications. To this purpose, polycarbonate substrates were irradiated at room temperature with low-energy metal ions (Cu + and Ni +) and with fluences in the range between 1 × 10 16 and 1 × 10 17 ions/cm 2, in order to promote the precipitation of dispersed metal nanoparticles or the formation of a continuous thin film. The nanoparticle morphology and the microstructural properties of polymer nanocomposites were investigated by glancing-incidence X-ray diffraction and transmission electron microscopy (TEM) measurements. At lower fluences (<5 × 10 16 ions/cm 2) a spontaneous precipitation of spherical-shaped metal nanoparticles occurred below the polymer top-surface (˜50 nm), whereas at higher fluences the aggregation of metal nanoparticles produced the formation of a continuous polycrystalline nanofilm. Furthermore, a characteristic surface plasmon resonance peak was observed for nanocomposites produced at lower ion fluences, due to the presence of Cu nanoparticles. A reduced electrical resistance of the near-surface metal-polymer nanocomposite was measured. The variation of electrical conductivity as a function of the applied surface load was measured: we found a linear relationship and a very small hysteresis.

  19. Ion implantation of silicon at the nanometer scale

    SciTech Connect

    Bianconi, Marco; Bergamini, Fabio; Cristiani, Stefano; Lulli, Giorgio

    2007-10-01

    SiO{sub 2} layers ({approx}0.5 {mu}m thick) thermally grown on (100) Si were irradiated with 12.5 MeV Ti ions at 10{sup 9} cm{sup -2} fluence, and subsequently exposed to the HF vapor, in order to selectively etch the latent tracks generated by the passage of swift ions. Nearly cylindrical nanoholes having diameters as small as 25 nm, with an average value of 54{+-}5 nm, were generated by this procedure. The nanopatterned SiO{sub 2} layer served as a mask for selective amorphization of the underlying Si, achieved by implantation with 180 keV Ar{sup +} ions at a fluence of 2.0x10{sup 15} cm{sup -2}. Dip in aqueous HF solution was then performed to selectively etch ion amorphized Si, thus transferring the nanometric pattern of the SiO{sub 2} mask to the underlying substrate. As expected, the maximum depth of amorphizazion in Si, and consequently of etching depth, decreases when the hole radius decreases below values of the order of the lateral ion straggling. The effect has been characterized and investigated by the comparison of experiments and three dimensional Monte Carlo simulations.

  20. Ion-implanted GaN junction field effect transistor

    SciTech Connect

    Zolper, J.C.; Shul, R.J.; Baca, A.G.; Wilson, R.G.; Pearton, S.J.; Stall, R.A.

    1996-04-01

    Selective area ion implantation doping has been used to fabricate GaN junction field effect transistors (JFETs). {ital p}-type and {ital n}-type doping was achieved with Ca and Si implantation, respectively, followed by a 1150{degree}C rapid thermal anneal. A refractory W gate contact was employed that allows the {ital p}-gate region to be self-aligned to the gate contact. A gate turn-on voltage of 1.84 V at 1 mA/mm of gate current was achieved. For a {approximately}1.7 {mu}m{times}50 {mu}m JFET with a {minus}6 V threshold voltage, a maximum transconductance of 7 mS/mm at {ital V}{sub GS}={minus} 2V and saturation current of 33 mA/mm at {ital V}{sub GS}=0 V were measured. These results were limited by excess access resistance and can be expected to be improved with optimized {ital n}{sup +} implants in the source and drain regions. {copyright} {ital 1996 American Institute of Physics.}

  1. Ion-implanted high microwave power indium phosphide transistors

    NASA Technical Reports Server (NTRS)

    Biedenbender, Michael D.; Kapoor, Vik J.; Messick, Louis J.; Nguyen, Richard

    1989-01-01

    Encapsulated rapid thermal annealing (RTA) has been used in the fabrication of InP power MISFETs with ion-implanted source, drain, and active-channel regions. The MISFETs had a gate length of 1.4 microns. Six to ten gate fingers per device, with individual gate finger widths of 100 or 125 microns, were used to make MISFETs with total gate widths of 0.75, 0.8, or 1 mm. The source and drain contact regions and the channel region of the MISFETs were fabricated using Si implants in InP at energies from 60 to 360 keV with doses of (1-560) x 10 to the 12th/sq cm. The implants were activated using RTA at 700 C for 30 sec in N2 or H2 ambients using an Si3N4 encapsulant. The high-power high-efficiency MISFETs were characterized at 9.7 GHz, and the output microwave power density for the RTA conditions used was as high as 2.4 W/mm. For a 1-W input at 9.7 GHz gains up to 3.7 dB were observed, with an associated power-added efficiency of 29 percent and output power density 70 percent greater than that of GaAs MESFETs.

  2. Ion beam technology applications study. [ion impact, implantation, and surface finishing

    NASA Technical Reports Server (NTRS)

    Sellen, J. M., Jr.; Zafran, S.; Komatsu, G. K.

    1978-01-01

    Specific perceptions and possible ion beam technology applications were obtained as a result of a literature search and contact interviews with various institutions and individuals which took place over a 5-month period. The use of broad beam electron bombardment ion sources is assessed for materials deposition, removal, and alteration. Special techniques examined include: (1) cleaning, cutting, and texturing for surface treatment; (2) crosslinking of polymers, stress relief in deposited layers, and the creation of defect states in crystalline material by ion impact; and (3) ion implantation during epitaxial growth and the deposition of neutral materials sputtered by the ion beam. The aspects, advantages, and disadvantages of ion beam technology and the competitive role of alternative technologies are discussed.

  3. Ion implantation doping and high temperature annealing of GaN

    SciTech Connect

    Zolper, J.C.; Crawford, M.H.; Howard, A.J. |

    1995-12-31

    The III-V nitride-containing semiconductors InN, GaN, and AIN and their ternary alloys are the focus of extensive research for application to visible light emitters and as the basis for high temperature electronics. Recent advances in ion implantation doping of GaN and studies of the effect of rapid thermal annealing up to 1100{degrees}C are making new device structures possible. Both p- and n-type implantation doping of GaN has been achieved using Mg co-implanted with P for p-type and Si-implantation for n-type. Electrical activation was achieved by rapid thermal anneals in excess of 1000{degrees}C. Atomic force microscopy studies of the surface of GaN after a series of anneals from 750 to 1100{degrees}C shows that the surface morphology gets smoother following anneals in Ar or N{sub 2}. The photoluminescence of the annealed samples also shows enhanced bandedge emission for both annealing ambients. For the deep level emission near 2.2 eV, the sample annealed in N{sub 2} shows slightly reduced emission while the sample annealed in Ar shows increased emission. These annealing results suggest a combination of defect interactions occur during the high temperature processing.

  4. Optical waveguides fabricated by nitrogen ion implantation in fused silica

    NASA Astrophysics Data System (ADS)

    Liu, Chun-Xiao; Fu, Li-Li; Zheng, Rui-Lin; Guo, Hai-Tao; Zhou, Zhi-Guang; Li, Wei-Nan; Lin, She-Bao; Wei, Wei

    2016-02-01

    We report on the fabrication of waveguides in fused silica using 4.5-MeV nitrogen ion implantation with a fluence of 5.0×1014 ions/cm2. The prism-coupling method was employed to measure the effective refractive indices of guiding modes at the wavelengths of 632.8 and 1539 nm. The effective refractive indices of the first few modes were higher than that of the substrate. The refractive index profiles at 632.8 and 1539 nm were reconstructed by the reflectivity calculation method. Positive index changes were induced in the waveguide layers. The end-face coupling method was used to measure the near-field light intensity distributions at the wavelength of 632.8 nm and the finite-difference beam propagation method was applied to simulate the guided mode profile at the wavelength of 1539 nm. The waveguide structures emerge as candidates for integrated photonic devices.

  5. Optically active surfaces formed by ion implantation and thermal treatment

    SciTech Connect

    Gea, L.A.; Boatner, L.A.; Evans, H.M.; Zuhr, R.

    1996-08-01

    Embedded VO{sub 2} precipitates have been formed in single-crystal sapphire by the ion co-implantation of vanadium and oxygen and subsequent thermal annealing. The embedded VO{sub 2} particles have been shown to exhibit an optical switching behavior that is comparable to that of continuous thin films. In this work, the mechanisms of formation of these optically active particles are investigated. It is shown that precipitation of the vanadium dioxide phase is favored when the thermal treatment is performed on an ion-damaged but still crystalline (rather than amorphized) Al{sub 2}O{sub 3} substrate. The best optical switching behavior is observed in this case, and this behavior is apparently correlated with a more-favorable dispersion of VO{sub 2} small particles inside the matrix.

  6. Superconducting Properties of Ion-Implanted Gold - Thin Films.

    NASA Astrophysics Data System (ADS)

    Jisrawi, Najeh Mohamed

    The superconducting properties of thin Au _{x}rm Si_{1-x} films prepared by ion beam implantation and ion beam mixing are studied. The films are prepared by evaporation of single Au layers on Si substrates and mixing them with Si, Ar, or Xe, or by Xe beam mixing of alternate multilayers of Au and Si sputtered on rm Al_2 O_3 substrates. The superconducting transition temperature and upper critical fields are determined by measuring the temperature and magnetic field dependence of resistivity. Temperatures as low as 20mK and magnetic fields as high as 8 T were used. Superconductivity in these films is discussed in connection with metastable metallic phases that are reportedly produced in the Au -Si system by high quenching rate preparation techniques like quenching from the vapor or the melt or ion implantation. Preliminary structural studies provide evidence for the existence of these phases and near-edge X-ray absorption and X-ray photoelectron spectroscopy measurements indicate a metallic type of bonding from which compound formation is inferred. The quality of the films is strongly dependent on the conditions of implantation. The maximum superconducting transition temperature attained is about 1.2 K. The upper critical fields have a maximum of 6T. An unusual double transition in the field dependence of resistivity is observed at low temperatures. The effect is very pronounced at compositions near x = 0.5 where the maximum T_{c} occurs. A model is presented to explain this result which invokes the properties of the metastable metallic phases and assumes the formation of more than two such phases in the same sample as the implantation dose increases. The Si-Au interface plays an important role in understanding the model and in interpreting the results of this thesis in general. The origin of superconductivity in the Au -Si system is discussed by relating the experimental results to the various mechanisms suggested in the literature. The implications of the study of

  7. Ion enhanced deposition by dual titanium and acetylene plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    Zeng, Z. M.; Tian, X. B.; Chu, P. K.

    2003-01-01

    Plasma immersion ion implantation and deposition (PIII-D) offers a non-line-of-sight fabrication method for various types of thin films on steels to improve the surface properties. In this work, titanium films were first deposited on 9Cr18 (AISI440) stainless bearing steel by metal plasma immersion ion implantation and deposition (MePIII-D) using a titanium vacuum arc plasma source. Afterwards, carbon implantation and carbon film deposition were performed by acetylene (C2H2) plasma immersion ion implantation. Multiple-layered structures with superior properties were produced by conducting Ti MePIII-D + C2H2 PIII successively. The composition and structure of the films were investigated employing Auger electron spectroscopy and Raman spectroscopy. It is shown that the mixing for Ti and C atoms is much better when the target bias is higher during Ti MePIII-D. A top diamond-like carbon layer and a titanium oxycarbide layer are formed on the 9Cr18 steel surface. The wear test results indicate that this dual PIII-D method can significantly enhance the wear properties and decrease the surface friction coefficient of 9Cr18 steel.

  8. Electrical measurements on ion-implanted LPCVD polycrystalline silicon films

    NASA Astrophysics Data System (ADS)

    Huang, Ruey-Shing; Cheng, Chin-Hsiung; Liu, J. C.; Lee, M. K.; Chen, C. T.

    1983-07-01

    The electrical conduction properties of ion implanted polycrystalline silicon films have been studied. The polysilicon films were deposited by pyrolysis of silane at 647°C in LPCVD system onto oxide-coated silicon wafers to a thickness of 0.6 μm. Dopants were itroducd by implanting with boron or phosphorus ions, accelerated to 145 keV; doses ranged from 1 × 10 12 cm -2 to 1 × 10 15 cm -2. Film resistivities spanning 8 orders of magnitude were obtained using this doping range. Current-voltage characteristics of polysilicon resistors were measured at temperatures ranging from 24 to 140°C. The associated barrier heights and activation energies were derived. The grain-boundary trapping states density was estimated to be 5 × 10 12 cm -2. We found that both dopant atom segregation and carrier trapping at the grain boundaries play important roles in polysilicon electrical conduction properties. However, within the dose range studies, the dopant atom segragation is most detrimental to the film conductivity for doses < 1 × 10 13 cm -2; as the dose is increased, carrier trapping effects become more pronounced for doses up to 5 × 10 14 cm -2. For doses ⩾ 5 × 10 14 cm -2, conduction due to carriers tunneling through the potential barriers at grain boundaries has to be considered.

  9. Influence of the chemical nature of implanted ions on the structure of a silicon layer damaged by implantation

    SciTech Connect

    Shcherbachev, K. D. Voronova, M. I.; Bublik, V. T.; Mordkovich, V. N. Pazhin, D. M.; Zinenko, V. I.; Agafonov, Yu. A.

    2013-12-15

    The influence of the implantation of silicon single crystals by fluorine, nitrogen, oxygen, and neon ions on the distribution of strain and the static Debye-Waller factor in the crystal lattice over the implanted-layer depth has been investigated by high-resolution X-ray diffraction. The density depth distribution in the surface layer of native oxide has been measured by X-ray reflectometry. Room-temperature implantation conditions have ensured the equality of the suggested ranges of ions of different masses and the energies transferred by them to the target. It is convincingly shown that the change in the structural parameters of the radiation-damaged silicon layer and the native oxide layer depend on the chemical activity of the implanted ions.

  10. Peripheral nerve regeneration through a silicone chamber implanted with negative carbon ions: Possibility to clinical application

    NASA Astrophysics Data System (ADS)

    Ikeguchi, Ryosuke; Kakinoki, Ryosuke; Tsuji, Hiroshi; Yasuda, Tadashi; Matsuda, Shuichi

    2014-08-01

    We investigated whether a tube with its inner surface implanted with negative-charged carbon ions (C- ions) would enable axons to extend over a distance greater than 10 mm. The tube was found to support nerves regenerating across a 15-mm-long inter-stump gap. We also investigated whether a C- ion-implanted tube pretreated with basic fibroblast growth factor (bFGF) promotes peripheral nerve regeneration. The C- ion implanted tube accelerated nerve regeneration, and this effect was enhanced by bFGF. Silicone treated with C- ions showed increased hydrophilic properties and cellular affinity, and axon regeneration was promoted with this increased biocompatibility.

  11. Studies of iron exposed to heavy ion implantation using positron annihilation spectroscopy

    NASA Astrophysics Data System (ADS)

    Horodek, P.; Dryzek, J.; Skuratov, V. A.

    2016-05-01

    Variable energy positron beam and positron lifetime spectroscopy were used to study pure iron exposed to irradiation with 167 MeV Xe26+ heavy ions with different doses of 1012, 1013, 5×1013, 1014 ions/cm2. The positron lifetime spectroscopy revealed the presence of large cluster of about 15-27 vacancies and dislocations. The dislocations are distributed at the depth of about 18 μm i.e. almost twice deeper than the ion implantation range from the surface exposed to the heavy ions implantation. Possible explanation is the long-range effect attributed to the ion implantation into materials.

  12. Recent advancements in ion concentration polarization.

    PubMed

    Li, Min; Anand, Robbyn K

    2016-06-21

    In this minireview, we discuss advancements in ion concentration polarization (ICP)-based preconcentration, separation, desalination, and dielectrophoresis that have been made over the past three years. ICP as a means of controlling the distribution of the ions and electric field in a microfluidic device has rapidly expanded its areas of application. Recent advancements have focused on the development of ion-permselective materials with tunable dimensions and surface chemistry, adaptation to paper microfluidics, higher-throughput device geometries, and coupling ICP with other separation (isotachophoresis and dielectrophoresis) and fluidic (valve and droplet microfluidic) strategies. These studies have made great strides toward solving real-world problems such as low-cost and rapid analysis, accessible desalination technology, and single-cell research tools. PMID:26965754

  13. Near-surface recrystallization of the amorphous implanted layer of ion implanted 6H-SiC

    NASA Astrophysics Data System (ADS)

    Kuhudzai, R. J.; van der Berg, N. G.; Malherbe, J. B.; Hlatshwayo, T. T.; Theron, C. C.; Buys, A. V.; Botha, A. J.; Wendler, E.; Wesch, W.

    2014-08-01

    The recrystallization and subsequent crystal growth during annealing of amorphous surface layers on 6H-SiC produced by ion implantation is investigated. Amorphous surface layers were produced by ion implantation of 360 keV ions of iodine, silver, xenon, cesium and strontium into single crystalline 6H-silicon carbide samples. The ion fluence for all the implantations were in the order of 1016 cm-2. Vacuum annealing of the damaged silicon carbide samples was then performed. The microstructure of SiC surfaces before and after annealing was investigated using a high resolution field emission scanning electron microscope (SEM). SEM analysis was complimented by Atomic Force Microscopy (AFM). SEM images acquired by an in-lens detector using an accelerating voltage of 2 kV show nano-crystallites developed for all implanted samples after annealing. Larger and more faceted crystallites along with elongated thin crystallites were observed for iodine and xenon implanted 6H-SiC. Crystallites formed on surfaces implanted with strontium and cesium were smaller and less faceted. Strontium, silver and cesium implanted samples also exhibited more cavities on the surface. AFM was used to evaluate the effect of annealing on the surface roughness. For all the amorphous surfaces which were essentially featureless, the root mean square (rms) roughness was approximately 1 nm. The roughness increased to approximately 17 nm for the iodine implanted sample after annealing with the surface roughness below this value for all the other samples. AFM also showed that the largest crystals grew to heights of about 17, 20, 45, 50 and 65 nm for Sr, Cs, Ag, Xe and I implanted samples after annealing at 1200 °C for 5 h respectively. SEM images and AFM analysis suggest that iodine is more effective in promoting crystal growth during the annealing of bombardment-induced amorphous SiC layers than the rest of the ions we implanted. In samples of silicon carbide co-implanted with iodine and silver, few

  14. Structural modifications of alumina implanted with zirconium, copper, and titanium ions

    NASA Astrophysics Data System (ADS)

    Bigarré, J.; Fayeulle, S.; Tréheux, D.; Moncoffre, N.

    1997-10-01

    Microstructural modifications (amorphization, lattice deformation, phase transformations) in alumina induced by implantation of zirconium, copper, or titanium ions and by postimplantation thermal annealings were studied using grazing incidence x-ray diffraction. It was shown that the amount of lattice deformation and the type of damage resulting in the lattice depend on the ion implanted. When zirconium was implanted, the alumina lattice was highly deformed. Amorphization was observed when a high ion dose was implanted. Copper implantation led to the formation of gamma alumina. With titanium ions, very high strain was created and delta alumina was formed. After postimplantation annealings, lattices returned to their equilibrium state through crystallization of alpha alumina and precipitation of oxides of the implanted species (ZrO2, CuO and CuAl2O4, and TiO2).

  15. Annealing of damage and stability of implanted ions in ZnO crystals

    SciTech Connect

    Sonder, E.; Zuhr, R.A.; Valiga, R.E.

    1988-08-01

    The annealing of Bi, Cr, and Mn, implanted in ZnO, has been studied by Rutherford backscattering, ion channeling, and secondary ion mass spectroscopy. Implantation of approx.10/sup 16/ ions/cm/sup 2/ of any of these elements produces large concentrations of Zn interstitials, but no completely amorphous region. The temperature at which these interstitials anneal is a function of the implant species. Other defects produced by the implantation, which give rise to dechanneling and a consequent increased scattering probability in the tails of backscattering spectra, anneal at significantly higher temperature. This annealing is also a function of the implant species. Motion of the implant ions themselves does not occur when the interstitials anneal; it takes place above 700 /sup 0/C for Bi and Mn, and above 1000 /sup 0/C for Cr.

  16. Influence of Temperature on Nitrogen Ion Implantation of Ti6Al4V Alloy

    NASA Astrophysics Data System (ADS)

    Zhao, Qing; Zheng, Yong-zhen; Mo, Zhi-tao; Tang, De-li; Tong, Hong-hui; Geng, Man

    2001-04-01

    In order to achieve increased layer thickness, and wearing resistance, enhanced ion implantation with nitrogen has been carried out at temperatures of 100, 200, 400, and 600°C with a dose of 4×1018 ions cm-2. Using the Plasma Source Ion Implantation (PSII) device, specimens of Ti6Al4V alloy were implanted at elevated temperatures, using the ion flux as the heating source. Auger Electron Spectroscopy (AES), Scanning Electron Microscopy (SEM), x-ray Diffraction (XRD), micro-hardness measurements and pin-on-disk wearing tester were utilized to evaluate the surface property improvements. The thickness of the implanted layer increased by about an order of magnitude when the temperature was elevated from 100 to 600°C. Higher surface hardness and wearing resistance was also obtained in implantation under higher temperature. XRD image showed the presence of titanium nitrides on the implanted surface.

  17. Magnesium aluminate planar waveguides fabricated by C-ion implantation with different energies and fluences

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

    We report on MgAl2O4 planar waveguides produced using different energies and fluences of C-ion implantation at room temperature. Based on the prism coupling method and end-face coupling measurements, light could propagate in the C-ion-implanted samples. The Raman spectra results indicate that the MgAl2O4 crystal lattice was damaged during the multi-energy C implantation process, whereas the absorption spectra were hardly affected by the C-ion implantation in the visible and infrared bands.

  18. Fluorescence effect of ion-implanted sapphire doped with Ag/Cu/Fe elements

    NASA Astrophysics Data System (ADS)

    Chen, Hua-jian; Wang, Yu-hua; Zhang, Xiao-jian; Dai, Hou-mei; Ji, Ling-ling; Wang, Ru-wu; Wang, Deng-jing; Lu, Jian-duo; Zheng, Li-rong

    2015-11-01

    The fluorescence effect and microstructure of the nanocomposite samples prepared by ion implantation have been studied in the subsurface area. Based on the UV-vis and VUV data, the luminescence properties of implanted samples have been presented and discussed. The research indicates that the surface plasma resonance has an impact on the fluorescence effect notably. In addition, the fluorescence performance of the substrates implanted with ions is related to the outermost electron number of the injection element. And SRIM is used to analyze the energy loss in the process of ion implantation.

  19. Modification of anti-bacterial surface properties of textile polymers by vacuum arc ion source implantation

    NASA Astrophysics Data System (ADS)

    Nikolaev, A. G.; Yushkov, G. Yu.; Oks, E. M.; Oztarhan, A.; Akpek, A.; Hames-Kocabas, E.; Urkac, E. S.; Brown, I. G.

    2014-08-01

    Ion implantation provides an important technology for the modification of material surface properties. The vacuum arc ion source is a unique instrument for the generation of intense beams of metal ions as well as gaseous ions, including mixed metal-gas beams with controllable metal:gas ion ratio. Here we describe our exploratory work on the application of vacuum arc ion source-generated ion beams for ion implantation into polymer textile materials for modification of their biological cell compatibility surface properties. We have investigated two specific aspects of cell compatibility: (i) enhancement of the antibacterial characteristics (we chose to use Staphylococcus aureus bacteria) of ion implanted polymer textile fabric, and (ii) the "inverse" concern of enhancement of neural cell growth rate (we chose Rat B-35 neuroblastoma cells) on ion implanted polymer textile. The results of both investigations were positive, with implantation-generated antibacterial efficiency factor up to about 90%, fully comparable to alternative conventional (non-implantation) approaches and with some potentially important advantages over the conventional approach; and with enhancement of neural cell growth rate of up to a factor of 3.5 when grown on suitably implanted polymer textile material.

  20. Locally Advanced Breast Cancer: Autologous Versus Implant-based Reconstruction

    PubMed Central

    Prousskaia, Elena; Chow, Whitney; Angelaki, Anna; Cirwan, Cleona; Hamed, Hisham; Farhadi, Jian

    2016-01-01

    Background: Recent papers and guidelines agree that patients with locally advanced breast cancer (LABC) should be offered breast reconstruction. Yet, the type of reconstruction in this group of patients is still a point of controversy. Methods: One hundred fourteen patients, treated for LABC from 2007 to 2013, were divided into 3 groups based on the reconstructive option: no reconstruction (NR), implant-based/expander-based reconstruction (IBR), and autologous tissue reconstruction (ATR). We analyzed demographics and compared delay in adjuvant therapy, length of hospitalization, surgical complications, failure of reconstruction, local recurrence, and disease-free survival. Results: Twenty-six patients had NR, 38 had IBR, and 50 had ATR. No significant difference was found in the percentage of patients who had their adjuvant treatment delayed [16% (NR) vs 22% (IBR) vs 14% (ATR)]. Mean length of hospitalization for the NR, IBR, and ATR groups was 2.7, 6, and 7.5 days, respectively. Complication rates requiring readmission were 36% (NR), 42% (IBR), and 32% (ATR). In the IBR group, 37% of implants were removed because of complications. Failure of reconstruction was 37% and 0% for the IBR and ATR groups, respectively. Local recurrence rates in the NR and Reconstruction (groups IBR and ATR combined) groups were 7% and 2%, respectively. Mean survival times in patients were 18 (NR), 10.3 (IBR), and 12.2 (ATR) months. Conclusions: No significant difference was found in the hospital stay length, adjuvant treatment delay, and complication rates between IBR and ATR. High rates of failed reconstruction suggest that the use of implants should be considered very carefully in patients with LABC. PMID:27014551

  1. Ion Implanted Nanolayers in Alloys and Ceramic Coatings for Improved Resistance to High-Temperature Corrosion

    NASA Astrophysics Data System (ADS)

    Werner, Z.; Szymczyk, W.; Piekoszewski, J.

    Ion implantation effects on resistance of alloys and ceramic coatings to the high-temperature corrosion have been reviewed. The most significant results on implantation of reactive elements (Y, La, Ce and other rare earth elements) into alloys and aluminum, boron, silicon, tantalum, and titanium into ceramic coatings have been cited. Ion implantation affects not only the oxide growth rate, but also seems to modify the growth mechanism and the oxide structure.

  2. Cell attachment of polypropylene surface-modified by COOH + ion implantation

    NASA Astrophysics Data System (ADS)

    Li, D. J.; Niu, L. F.

    2002-06-01

    Carboxy ion (COOH +) implantation was performed at the energy of 50 keV with fluences ranging from 1×10 14 to 1×10 15 ions/cm 2 at room temperature for polypropylene (PP). The effects of ion implantation on cells (immune macrophages, 3T3 mouse fibroblasts and human endothelial cells) were studied in vitro. Tests of cell attachment gave interesting results that the 3T3 mouse fibroblasts and human endothelial cells cultured on the surface of the implanted PP showed much better attachment and proliferation than that on pristine PP. At the same time, the COOH + ion implantation also induced low macrophage attachment with normal cellular morphology. Results of X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared (FTIR) analysis showed that COOH + ion implantation caused the rearrangement of chemical bonds and the formation of some new O-containing groups, which was responsible for the enhancement of the biocompatibility of PP.

  3. Comparison of Wear Resistance Mechanisms of Die Steel Implanted with C and mo Ions

    NASA Astrophysics Data System (ADS)

    Cheng, M. F.; Yang, J. H.; Luo, X. D.; Zhang, T. H.

    Mo and C ions extracted from a metal vapor vacuum arc ion source were implanted into the surface of die steel (H13) to compare the wear resistance mechanisms of the implanted samples, respectively. The concentration depth profiles of implanted ions were measured using Rutherford backscattering spectroscopy and calculated by a code called TRIDYN. The structures of the implanted steel were observed by X-ray photoelectron spectroscopy and grazing-angle X-ray diffraction, respectively. It was found that the conventional heat-treated H13 steel could not be further hardened by the subsequent implanted C ions, and the thickness of the implanted layer was not an important factor for the Mo and C ion implantation to improve the wear resistance of the H13 steel. Mo ion implantation could obviously improve the wear resistance of the steel at an extraction voltage of 48 kV and a dose of 5 × 1017cm-2 due to formation of a modification layer of little oxidation with Mo2C in the implanted surface.

  4. Surface stiffening and enhanced photoluminescence of ion implanted cellulose - polyvinyl alcohol - silica composite.

    PubMed

    Shanthini, G M; Sakthivel, N; Menon, Ranjini; Nabhiraj, P Y; Gómez-Tejedor, J A; Meseguer-Dueñas, J M; Gómez Ribelles, J L; Krishna, J B M; Kalkura, S Narayana

    2016-11-20

    Novel Cellulose (Cel) reinforced polyvinyl alcohol (PVA)-Silica (Si) composite which has good stability and in vitro degradation was prepared by lyophilization technique and implanted using N(3+) ions of energy 24keV in the fluences of 1×10(15), 5×10(15) and 1×10(16)ions/cm(2). SEM analysis revealed the formation of microstructures, and improved the surface roughness on ion implantation. In addition to these structural changes, the implantation significantly modified the luminescent, thermal and mechanical properties of the samples. The elastic modulus of the implanted samples has increased by about 50 times compared to the pristine which confirms that the stiffness of the sample surface has increased remarkably on ion implantation. The photoluminescence of the native cellulose has improved greatly due to defect site, dangling bonds and hydrogen passivation. Electric conductivity of the ion implanted samples was improved by about 25%. Hence, low energy ion implantation tunes the mechanical property, surface roughness and further induces the formation of nano structures. MG63 cells seeded onto the scaffolds reveals that with the increase in implantation fluence, the cell attachment, viability and proliferation have improved greatly compared to pristine. The enhancement of cell growth of about 59% was observed in the implanted samples compared to pristine. These properties will enable the scaffolds to be ideal for bone tissue engineering and imaging applications. PMID:27561534

  5. Computer Simulation of Plasma Immersion Ion Implantation and Deposition

    NASA Astrophysics Data System (ADS)

    Miyagawa, Yoshiko; Tanaka, Masaaki; Nakadate, Hiroshi; Nakao, Setsuo; Miyagawa, Soji

    By using a newly developed simulation program "PEGASUS", plasma behavior was analyzed for the plasma immersion ion implantation and deposition (PIII&D). For plasma analysis of low pressure gas which is used in PIII&D, the software uses a particle in cell (PIC) method for the analysis of electric and magnetic fields and the motion of charged particles. A Monte Carlo collision method is used for collisions of ions, electrons and neutrals in the plasma, and the dynamic-SASAMAL code is used for the ion-solid surface interactions. Spatial distributions of potential, electron density and ion density together with the ion flux distribution on the target surface were calculated for the case where a negative pulse voltage was applied to a trench shaped target immersed in a high density Ar plasma (1010 cm-3). The time evolution of sheath length obtained by the simulations for a flat plane part of the surface agreed with the analytical result obtained by the Child-Langmuir method. In a bipolar pulse PIII&D system, a positive and a negative pulse voltages are applied alternately to a workpiece without any other external plasma source. Simulation has been conducted for a target immersed in a very low density Ar plasma (107 cm-3) to compare the plasma generated by a negative and a positive pulse voltage applied to the target. When a negative pulse voltage is applied to the target, only a weak plasma is generated. In contrast to it, when a positive pulse voltage is applied, a two-order or more high density plasma is generated under the same condition. The plasma behavior around a trench shaped target is also presented.

  6. Multiple Ion Implantation Effects on Wear and Wet Ability of Polyethylene Based Polymers

    NASA Astrophysics Data System (ADS)

    Torrisi, L.; Visco, A. M.; Campo, N.

    2004-10-01

    Polyethylene based polymers were ion implanted with multiple irradiations of different ions (N+, Ar+ and Kr+) at energies between 30 keV and 300 keV and doses ranging between 1013 and 1016 ions/cm2. The ion implantation dehydrogenises the polyethylene inducing cross-link effects in the residual polymer carbons. At high doses the irradiated surface show properties similar to graphite surfaces. The depth of the modified layers depends on the ion range in polyethylene at the incident ion energy. The chemical modification depends on the implanted doses and on the specie of the incident ions. A "pin-on-disc" machine was employed to measure the polymer wear against AISI-316 L stainless steel. A "contact-angle-test" machine was employed to measure the wet ability of the polymer surface for 1 μl pure water drop. Measurements demonstrate that the multiple ion implantation treatments decrease the surface wear and the surface wetting and produce a more resistant polymer surface. The properties of the treated surfaces improves the polymer functionality for many bio-medical applications, such as those relative to the polyethylene friction discs employed in knee and hip prosthesis joints. The possibility to use multiply ion implantations of polymers with traditional ion implanters and with laser ion sources producing plasmas is investigated.

  7. A one-dimensional collisional model for plasma-immersion ion implantation

    SciTech Connect

    Vahedi, V.; Lieberman, M.A.; Alves, M.V.; Verboncoeur, J.P.; Birdsall, C.K. )

    1991-02-15

    Plasma-immersion ion implantation (also known as plasma-source ion implantation) is a process in which a target is immersed in a plasma and a series of large negative-voltage pulses are applied to it to extract ions from the plasma and implant them into the target. A general one-dimensional model is developed to study this process in different coordinate systems for the case in which the pressure of the neutral gas is large enough that the ion motion in the sheath can be assumed to be highly collisional.

  8. Ion beam sputter modification of the surface morphology of biological implants

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Banks, B. A.

    1976-01-01

    The surface chemistry and texture of materials used for biological implants may significantly influence their performance and biocompatibility. Recent interest in the microscopic control of implant surface texture has led to the evaluation of ion beam sputtering as a potentially useful surface roughening technique. Ion sources, similar to electron bombardment ion thrusters designed for propulsive applications, are used to roughen the surfaces of various biocompatible alloys or polymer materials. These materials are typically used for dental implants, orthopedic prostheses, vascular prostheses, and artificial heart components. Masking techniques and resulting surface textures are described along with progress concerning evaluation of the biological response to the ion beam sputtered surfaces.

  9. Ion-beam-sputter modification of the surface morphology of biological implants

    NASA Technical Reports Server (NTRS)

    Weigand, A. J.; Banks, B. A.

    1977-01-01

    The surface chemistry and texture of materials used for biological implants may significantly influence their performance and biocompatibility. Recent interest in the microscopic control of implant surface texture has led to the evaluation of ion-beam sputtering as a potentially useful surface roughening technique. Ion sources, similar to electron-bombardment ion thrusters designed for propulsive applications, are used to roughen the surfaces of various biocompatible alloys or polymer materials. These materials are typically used for dental implants, orthopedic prostheses, vascular prostheses, and artificial heart components. Masking techniques and resulting surface textures are described along with progress concerning evaluation of the biological response to the ion-beam-sputtered surfaces.

  10. Ion implantation of erbium into polycrystalline cadmium telluride

    SciTech Connect

    Ushakov, V. V. Klevkov, Yu. V.; Dravin, V. A.

    2015-05-15

    The specific features of the ion implantation of polycrystalline cadmium telluride with grains 20–1000 μm in dimensions are studied. The choice of erbium is motivated by the possibility of using rare-earth elements as luminescent “probes” in studies of the defect and impurity composition of materials and modification of the composition by various technological treatments. From the microphotoluminescence data, it is found that, with decreasing crystal-grain dimensions, the degree of radiation stability of the material is increased. Microphotoluminescence topography of the samples shows the efficiency of the rare-earth probe in detecting regions with higher impurity and defect concentrations, including regions of intergrain boundaries.

  11. Structure and micro-mechanical properties of helium-implanted layer on Ti by plasma-based ion implantation

    NASA Astrophysics Data System (ADS)

    Ma, Xinxin; Li, Jinlong; Sun, Mingren

    2008-08-01

    The present paper concentrates on structure and micro-mechanical properties of the helium-implanted layer on titanium treated by plasma-based ion implantation with a pulsed voltage of -30 kV and doses of 3, 6, 9 and 12 × 10 17 ions/cm 2, respectively. X-ray photoelectron spectroscopy and transmission electron microscopy are employed to characterize the structure of the implanted layer. The hardnesses at different depths of the layer were measured by nano-indentation. We found that helium ion implantation into titanium leads to the formation of bubbles with a diameter from a few to more than 10 nm and the bubble size increases with the increase of dose. The primary existing form of Ti is amorphous in the implanted layer. Helium implantation also enhances the ingress of O, C and N and stimulates the formations of TiO 2, Ti 2O 3, TiO, TiC and TiN in the near surface layer. And the amount of the ingressed oxygen is obviously higher than those of nitrogen and carbon due to its higher activity. At the near surface layer, the hardnesses of all implanted samples increases remarkably comparing with untreated one and the maximum hardness has an increase by a factor of up to 3.7. For the samples implanted with higher doses of 6, 9 and 12 × 10 17 He/cm 2, the local displacement bursts are clearly found in the load-displacement curves. For the samples implanted with a lower dose of 3 × 10 17 He/cm 2, there is no obvious displacement burst found. Furthermore, the burst width increases with the increase of the dose.

  12. Open questions in electronic sputtering of solids by slow highly charged ions with respect to applications in single ion implantation

    SciTech Connect

    Schenkel, T.; Rangelow, I.W.; Keller, R.; Park, S.J.; Nilsson, J.; Persaud, A.; Radmilivitc, V.R.; Liddle, J.A.; Grabiec, P.; Bokor, J.; Schneider, D.H.

    2003-07-16

    In this article we discuss open questions in electronic sputtering of solids by slow, highly charged ions in the context of their application in a single ion implantation scheme. High yields of secondary electrons emitted when highly charged dopant ions impinge on silicon wafers allow for formation of non-Poissonian implant structures such as single atom arrays. Control of high spatial resolution and implant alignment require the use of nanometer scale apertures. We discuss electronic sputtering issues on mask lifetimes, and damage to silicon wafers.

  13. 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.

  14. Swelling or erosion on the surface of patterned GaN damaged by heavy ion implantation

    SciTech Connect

    Gao, Yuan; Lan, Chune; Xue, Jianming; Yan, Sha; Wang, Yugang; Xu, Fujun; Shen, Bo; Zhang, Yanwen

    2010-06-08

    Wurtzite undoped GaN epilayers (0 0 0 1) was implanted with 500 keV Au+ ions at room temperature under different doses, respectively. Ion implantation was performed through photoresist masks on GaN to produce alternating strips. The experimental results showed that the step height of swelling and decomposition in implanted GaN depended on ion dose and annealing temperature, i.e., damage level and its evolution. This damage evolution is contributed to implantation-induced defect production, and defect migration/accumulation occurred at different levels of displacement per atom. The results suggest that the swelling is due to the formation of porous structures in the amorphous region of implanted GaN. The decomposition of implanted area can be attributed to the disorder saturation and the diffusion of surface amorphous layer.

  15. Effects of ion implantation on the photoferroelectric properties of lead lanthanum zirconate titanate ceramics

    SciTech Connect

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

    1981-01-01

    Earlier studies of Ar-, Ar + Ne- and Ar + Ne + He- implanted ferroelectric-phase lead lanthanum zirconate titanate (PLZT) ceramics indicate that ion implantation can increase the intrinsic (near-uv) photoferroelectric sensitivity by more than four orders of magnitude compared to that of unimplanted PLZT. More recent studies involving implantation of chemically active ions, e.g., Al and Cr, indicate that the absorption spectrum of the implanted region can be extended from the near-uv to the visible, and that the extrinsic (visible-light) photoferroelectric sensitivity can be improved substantially with respect to that of PLZT implanted with inert ions. The results of these studies are reviewed and photographic sensitivities of Ar-, Ar + Ne-, Ar + Ne + He-, Al-, Cr-, Fe-, and Fe + Ne- implanted PLZT at both near-uv and visible-light wavelengths are compared with the sensitivities of other image storage media.

  16. High Curie temperature drive layer materials for ion-implanted magnetic bubble devices

    NASA Technical Reports Server (NTRS)

    Fratello, V. J.; Wolfe, R.; Blank, S. L.; Nelson, T. J.

    1984-01-01

    Ion implantation of bubble garnets can lower the Curie temperature by 70 C or more, thus limiting high temperature operation of devices with ion-implanted propagation patterns. Therefore, double-layer materials were made with a conventional 2-micron bubble storage layer capped by an ion-implantable drive layer of high Curie temperature, high magnetostriction material. Contiguous disk test patterns were implanted with varying doses of a typical triple implant. Quality of propagation was judged by quasistatic tests on 8-micron period major and minor loops. Variations of magnetization, uniaxial anisotropy, implant dose, and magnetostriction were investigated to ensure optimum flux matching, good charged wall coupling, and wide operating margins. The most successful drive layer compositions were in the systems (SmDyLuCa)3(FeSi)5O12 and (BiGdTmCa)3(FeSi)5O12 and had Curie temperatures 25-44 C higher than the storage layers.

  17. N and Cr ion implantation of natural ruby surfaces and their characterization

    NASA Astrophysics Data System (ADS)

    Rao, K. Sudheendra; Sahoo, Rakesh K.; Dash, Tapan; Magudapathy, P.; Panigrahi, B. K.; Nayak, B. B.; Mishra, B. K.

    2016-04-01

    Energetic ions of N and Cr were used to implant the surfaces of natural rubies (low aesthetic quality). Surface colours of the specimens were found to change after ion implantation. The samples without and with ion implantation were characterized by diffuse reflectance spectra in ultra violet and visible region (DRS-UV-Vis), field emission scanning electron microscopy (FESEM), selected area electron diffraction (SAED) and nano-indentation. While the Cr-ion implantation produced deep red surface colour (pigeon eye red) in polished raw sample (without heat treatment), the N-ion implantation produced a mixed tone of dark blue, greenish blue and violet surface colour in the heat treated sample. In the case of heat treated sample at 3 × 1017 N-ions/cm2 fluence, formation of colour centres (F+, F2, F2+ and F22+) by ion implantation process is attributed to explain the development of the modified surface colours. Certain degree of surface amorphization was observed to be associated with the above N-ion implantation.

  18. Oxygen incorporation in polyethylene and polypropylene implanted with F+, As+ and I+ ions at high dose

    NASA Astrophysics Data System (ADS)

    Hnatowicz, V.; Kvítek, J.; Švorčík, V.; Rybka, V.

    1994-04-01

    Samples of PolyPropylene (PP) and PolyEthylene (PE) implanted with 150 keV F+, As+ and I+ ions with a dose of 1×1015 cm-2 were studied using standard Rutherford Back Scattering (RBS) technique. No fluorine atoms above the present RBS detection limit were observed in the ion-implanted polymers. The measured depth profiles of As and I atoms are significantly broader than those predicted by the TRIM code for pristine polymers. The differences can be explained by stepwise polymer degradation due to ion bombardment. Massive oxidation of the ion-implanted polymers is observed. The oxidation rate and the resulting oxygen depth profile depend strongly on the polymer type and implanted ion mass. In the samples implanted with F+ ions, an uniformly oxidized layer is built up with a mean oxygen concentration of 15 at.%. In the samples implanted with As+ and I+ ions, a non-uniform oxygen depth distribution is observed with two concentration maxima on the sample surface and in a depth correlated with implanted ion range.

  19. Spectral Ellipsometry and Electron Backscatter Diffraction Analyses of Silicon Surfaces Implanted with Silver Ions

    NASA Astrophysics Data System (ADS)

    Bazarov, V. V.; Nuzhdin, V. I.; Valeev, V. F.; Vorobev, V. V.; Osin, Yu. N.; Stepanov, A. L.

    2016-03-01

    Amorphous silicon (a-Si) produced on surfaces of single-crystal substrates (c-Si) by low-energy low-dose implantation of silver ions is studied by spectral ellipsometry and electron backscatter diffraction. Implantation was done with an ion energy of 30 keV at a constant ion beam current density of 2 μA/cm2 and doses of 6.24·1012-1.25·1016 ions/cm2 on room temperature substrate targets. Irradiation was carried out with a current density of 0.1-5 μA/cm2 for implantation doses of 6.24·1013 and 1.87·1014 ions/cm2. It was found that spectral ellipsometry is an accurate andreliable method for monitoring low-dose ion implantation processes.

  20. Study on the Growth and the Photosynthetic Characteristics of Low Energy C+ Ion Implantation on Peanut

    PubMed Central

    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. PMID:23861939

  1. Depth profiles of MeV heavy ions implanted into Si and lithium triborate

    NASA Astrophysics Data System (ADS)

    Wang, Ke-Ming; Shi, Bo-Rong; Cue, Nelson; Shen, Ding-Yu; Chen, Feng; Wang, Xue-Lin; Lu, Fei

    2004-10-01

    MeV Cu + and Ni + ions were implanted into Si crystal and lithium triborate. The depth profiles of implanted Cu + and Ni + ions into Si and lithium triborate were measured by secondary ion mass spectrometry (SIMS). Mean projected range and range straggling extracted are compared with calculated values based on different versions of transport of ions in matter: TRIM'90, TRIM'98 and SRIM 2003. The results show that TRIM'90 has predicted well the experimental data of mean projected range and range straggling for MeV Cu + ions implanted into Si, the maximum differences between measured and calculated values are within 4%, but for the case of 2.0 MeV Ni + ions implanted into lithium triborate, the experimental value is significantly different from the calculated one based on TRIM'90.

  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. High current vacuum-arc ion source for ion implantation and coating deposition technologies

    SciTech Connect

    Ryabchikov, Alexander I.; Ryabchikov, Igor A.; Stepanov, Igor B.; Dektyarev, Sergey V.

    2006-03-15

    This work is devoted to the development and investigation of a high current ion source based on dc vacuum-arc plasma generation. Extraction and acceleration of ion beams are realized in a repetitively pulsed mode with the pulse repetition rate up to 200 pps, the pulse duration up to 400 {mu}s, the accelerating voltage up to 40 kV, and the pulsed ion-beam current up to 2 A. To remove microparticles from the vacuum-arc plasma a straight-line plasma filter is used. Examples of the source use for realization of high-intensity and high-concentration ion implantation regimes including those with formation of doped layers at depths that exceed ion projective range for more than an order of magnitude are presented. At the expense of change in order and intensity of ion and plasma material treatment, the advantage of application of one source for execution of material surface pretreatment and activation regimes, formation of wide transition layers between the substrate and coating, coating deposition, and high-intensity ion mixing using ions of the same type was shown.

  4. 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. PMID:21334957

  5. Swift and heavy ion implanted chalcogenide laser glass waveguides and their different refractive index distributions

    SciTech Connect

    Qiu Feng; Narusawa, Tadashi; Zheng Jie

    2011-02-10

    Planar waveguides have been fabricated in Nd- or Ho-doped gallium lanthanum sulfide laser glasses by 60 MeV Ar or 20 MeV N ion implantation. The refractive index profiles were reconstructed based on the results of prism coupling. The Ar implanted waveguides exhibit an approximate steplike distribution, while the N implanted ones show a ''well + barrier'' type. This difference can be attributed to the much lower dose of Ar ions. After annealing, the N implanted waveguides can support two modes at 1539 nm and have low propagation loss, which makes them candidates for novel waveguide lasers.

  6. Advance prototype silver ion water bactericide system

    NASA Technical Reports Server (NTRS)

    Jasionowski, W. J.; Allen, E. T.

    1974-01-01

    An advance prototype unit was designed and fabricated to treat anticipated fuel cell water. The unit is a single canister that contains a membrane-type prefilter and a silver bromide contacting bed. A seven day baseline simulated mission test was performed; the performance was satisfactory and the effluent water was within all specifications for potability. After random vibrations another seven day simulated mission test was performed, and results indicate that simulated launch vibrations have no effects on the design and performance of the advanced prototype. Bench tests and accelerated breadboard tests were conducted to define the characteristics of an upgraded model of the advance prototype unit which would have 30 days of operating capability. A preliminary design of a silver ion generator for the shuttle orbiter was also prepared.

  7. MAGNESIUM PRECIPITATION AND DIFUSSION IN Mg+ ION IMPLANTED SILICON CARBIDE

    SciTech Connect

    Jiang, Weilin; Jung, Hee Joon; Kovarik, Libor; Wang, Zhaoying; Roosendaal, Timothy J.; Zhu, Zihua; Edwards, Danny J.; Hu, Shenyang Y.; Henager, Charles H.; Kurtz, Richard J.; Wang, Yongqiang

    2015-03-02

    As a candidate material for fusion reactor applications, silicon carbide (SiC) undergoes transmutation reactions under high-energy neutron irradiation with magnesium as the major metallic transmutant; the others include aluminum, beryllium and phosphorus in addition to helium and hydrogen gaseous species. Calculations by Sawan et al. predict that at a dose of ~100 dpa (displacements per atom), there is ~0.5 at.% Mg generated in SiC. The impact of these transmutants on SiC structural stability is currently unknown. This study uses ion implantation to introduce Mg into SiC. Multiaxial ion-channeling analysis of the as-produced damage state indicates a lower dechanneling yield observed along the <100> axis. The microstructure of the annealed sample was examined using high-resolution scanning transmission electron microscopy. The results show a high concentration of likely non-faulted tetrahedral voids and possible stacking fault tetrahedra near the damage peak. In addition to lattice distortion, dislocations and intrinsic and extrinsic stacking faults are also observed. Magnesium in 3C–SiC prefers to substitute for Si and it forms precipitates of cubic Mg2Si and tetragonal MgC2. The diffusion coefficient of Mg in 3C–SiC single crystal at 1573 K has been determined to be 3.8 ± 0.4E-19 m2/s.

  8. Magnetic properties and recording performances of patterned media fabricated by nitrogen ion implantation

    NASA Astrophysics Data System (ADS)

    Hinoue, Tatsuya; Ito, Kenichi; Hirayama, Yoshiyuki; Ono, Toshinori; Inaba, Hiroshi

    2011-04-01

    Nitrogen ion implantation was performed on CoCrPt-SiO2 perpendicular media with a resist mask to fabricate patterned media. Signal amplitude and autocorrelation signal-to-noise ratio of the preamble pattern were measured to evaluate the quality of the pattern fabricated by the ion implantation. The signal-to-noise ratio and the jitter were closely related to the saturation magnetization of the ion-implanted area. The remained magnetization of the ion-implanted area probably affects edge roughness of the magnetic pattern. Larger reduction of the saturation magnetization at the ion-implanted area is important for obtaining higher signal quality. Off-track profiles and 747 curves were measured for 76-nm-pitch discrete track fabricated by ion implantation. The results show that discrete track recording had advantages over recording on continuous magnetic film, which indicates that the fabricated patterns were successfully isolated. The nitrogen ion implantation was effective in fabricating isolated magnetic tracks or isolated magnetic dots for the patterned media.

  9. Surface modification of poly(propylene carbonate) by oxygen ion implantation

    NASA Astrophysics Data System (ADS)

    Zhang, Jizhong; Kang, Jiachen; Hu, Ping; Meng, Qingli

    2007-04-01

    Poly(propylene carbonate) (PPC) was implanted by oxygen ion with energy of 40 keV. The influence of experimental parameters was investigated by varying ion fluence from 1 × 10 12 to 1 × 10 15 ions/cm 2. XPS, SEM, surface roughness, wettability, hardness, and modulus were employed to investigate structure and properties of the as-implanted PPC samples. Eight chemical groups, i.e., carbon, C sbnd H, C sbnd O sbnd C, C sbnd O, O sbnd C sbnd O, C dbnd O, ?, and ? groups were observed on surfaces of the as-implanted samples. The species and relative intensities of the chemical groups changed with increasing ion fluence. SEM images displayed that irradiation damage was related strongly with ion fluence. Both surface-recovering and shrunken behavior were observed on surface of the PPC sample implanted with fluence of 1 × 10 15 ions/cm 2. As increasing ion fluence, the surface roughness of the as-implanted PPC samples increased firstly, reached the maximum value of 159 nm, and finally decreased down the minimum value. The water droplet contact angle of the as-implanted PPC samples changed gradually with fluence, and reached the minimum value of 70° with fluence of 1 × 10 15 ions/cm 2. The hardness and modulus of the as-implanted PPC samples increased with increasing ion fluence, and reached their corresponding maximum values with fluence of 1 × 10 15 ions/cm 2. The experimental results revealed that oxygen ion fluence closely affected surface chemical group, morphology, surface roughness, wettability, and mechanical properties of the as-implanted PPC samples.

  10. Nonpolar III-nitride vertical-cavity surface-emitting lasers incorporating an ion implanted aperture

    NASA Astrophysics Data System (ADS)

    Leonard, J. T.; Cohen, D. A.; Yonkee, B. P.; Farrell, R. M.; Margalith, T.; Lee, S.; DenBaars, S. P.; Speck, J. S.; Nakamura, S.

    2015-07-01

    We report on our recent progress in improving the performance of nonpolar III-nitride vertical-cavity surface-emitting lasers (VCSELs) by using an Al ion implanted aperture and employing a multi-layer electron-beam evaporated ITO intracavity contact. The use of an ion implanted aperture improves the lateral confinement over SiNx apertures by enabling a planar ITO design, while the multi-layer ITO contact minimizes scattering losses due to its epitaxially smooth morphology. The reported VCSEL has 10 QWs, with a 3 nm quantum well width, 1 nm barriers, a 5 nm electron-blocking layer, and a 6.95- λ total cavity thickness. These advances yield a single longitudinal mode 406 nm nonpolar VCSEL with a low threshold current density (˜16 kA/cm2), a peak output power of ˜12 μW, and a 100% polarization ratio. The lasing in the current aperture is observed to be spatially non-uniform, which is likely a result of filamentation caused by non-uniform current spreading, lateral optical confinement, contact resistance, and absorption loss.

  11. Effect of dual ion implantation of calcium and phosphorus on the properties of titanium.

    PubMed

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

    2005-06-01

    This study is concerned with the effect of dual implantation of calcium and phosphorus upon the structure, corrosion resistance and biocompatibility of titanium. The ions were implanted in sequence, first Ca and then P, both at a dose of 10(17) ions/cm2 at a beam energy of 25 keV. Transmission electron microscopy was used to investigate the microstructure of the implanted layer. The chemical composition of the implanted layer was examined by XPS and SIMS. The corrosion resistance was determined by electrochemical methods in a simulated body fluid (SBF) at a temperature of 37 degrees C. The biocompatibility tests were performed in vitro in a culture of human-derived bone cells (HDBC) in contact with the tested materials. The viability of the cells was determined by an XTT assay and their activity by the measurements of the alkaline phosphatase activity in contact with implanted and non-implanted titanium samples. The in vitro examinations confirmed that, under the conditions prevailing during the experiments, the biocompatibility of Ca + P ion-implanted titanium was satisfactory. TEM results show that the surface layer formed by the Ca + P implantation is amorphous. The corrosion resistance of titanium, examined by the electrochemical methods, appeared to be increased after the Ca + P ion implantation. PMID:15603780

  12. Effects of oxygen ion implantation in spray-pyrolyzed ZnO thin films

    NASA Astrophysics Data System (ADS)

    Vijayakumar, K. P.; Ratheesh Kumar, P. M.; Sudha Kartha, C.; Wilson, K. C.; Singh, F.; Nair, K. G. M.; Kashiwaba, Y.

    2006-04-01

    ZnO thin films, prepared using the chemical spray pyrolysis technique, were implanted using 100 keV O+ ions. Both pristine and ion-implanted samples were characterized using X-ray diffraction, optical absorption, electrical resistivity measurements, thermally stimulated current measurements and photoluminescence. Samples retained their crystallinity even after irradiation at a fluence of 1015 ions/cm2. However, at a still higher fluence of 2 × 1016 ions/cm2, the films became totally amorphous. The optical absorption edge remained unaffected by implantation and optical absorption spectra indicated two levels at 460 and 510 nm. These were attributed to defect levels corresponding to zinc vacancies (VZn) and oxygen antisites (OZn), respectively. Pristine samples had a broad photoluminescence emission centred at 517 nm, which was depleted on implantation. In the case of implanted samples, two additional emissions appeared at 425 and 590 nm. These levels were identified as due to zinc vacancies (VZn) and oxygen vacancies (VO), respectively. The electrical resistivity of implanted samples was much higher than that of pristine, while photosensitivity decreased to a very low value on implantation. This can be utilized in semiconductor device technology for interdevice isolation. Hall measurements showed a marked decrease in mobility due to ion implantation, while carrier concentration slightly increased.

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

    SciTech Connect

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

    1996-12-31

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-09-01

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

  15. Characterization of silicon-gate CMOS/SOS integrated circuits processed with ion implantation

    NASA Technical Reports Server (NTRS)

    Woo, D. S.

    1977-01-01

    Progress in developing the application of ion implantation techniques to silicon gate CMOS/SOS processing is described. All of the conventional doping techniques such as in situ doping of the epi-film and diffusion by means of doped oxides are replaced by ion implantation. Various devices and process parameters are characterized to generate an optimum process by the use of an existing SOS test array. As a result, excellent circuit performance is achieved. A general description of the all ion implantation process is presented.

  16. Optical characteristics of Cu-nanocluster layers assembled by ion implantation

    SciTech Connect

    Haglund, R.F. Jr.; Yang, L. . Dept. of Physics and Astronomy); Magruder, R.H. III; Wittig, J.E. . Dept. of Materials Science and Engineering); Zuhr, R.A. )

    1991-01-01

    We have generated cluster layers in solid insulating substrates by implanting Cu ions into fused silica, creating thin layers ({approximately} 150 nm) of nonoclusters over a diameter of order 2 cm. Transmission electron microscopy shows that the size and size distribution can be controlled by the parameters of the ion implantation. We report measurements of the optical properties and nonlinear index of the refraction on these unusual solid-phase cluster materials as a function of total implanted-ion dose. 7 refs., 8 figs.

  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. Helium ion implantation in zirconium: Bubble formation and growth

    NASA Astrophysics Data System (ADS)

    Totemeier, Aaron Robert

    To evaluate the behavior of inert helium gas bubbles in zirconium three variants of the metal were implanted with 140 keV helium ions to a total fluence of 3x1017 cm--2 and characterized in cross-section TEM in their as-implanted state as well as during annealing at different temperatures. The three zirconium alloys included high-purity crystal bar material, Zircaloy-4, and a powder-metallurgically extruded material with high carbon and oxygen concentrations. At a sample depth consistent with a helium concentration of approximately 5 atomic percent, a change in the structure of the zirconium was observed a high density region of small (4nm diameter) bubbles formed at concentrations above 10 atom percent. Initial bubble formation and growth was observed to occurred at a temperature between 400-450 °C and these initial bubbles had a unique planar geometry prior to migration and coalescence into more three-dimensional bubbles. These planar bubbles appear to be aligned with major axes parallel to the TEM specimen surface and their formation and growth is possibly due to an increase in the thermal vacancy flux within the zirconium. The observations of bubble response to high temperature annealing suggest that in zirconium, as in other metals, maximum bubble size is weakly dependent on annealing time, whereas the bubble size distribution is strongly dependent on time. Specimens that underwent a prolonged room temperature aging developed a multimodal bubble size distribution within the high density region of small bubbles, concentrated near the highest helium concentration depth.

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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, Fe3O4. We implanted Kr ions accelerated at 30 kV on 13-nm-thick Fe3O4 thin films at dosages of (1-40) × 1014 ions/cm2. Magnetization decreased with increase in ion dosages and disappeared when irradiation was greater than 2 × 1015 ions/cm2 of Kr ions. These dosages are more than ten times smaller than that used in the N2 implantation for metallic and oxide ferromagnets. Both the temperature dependence of magnetization and the Mössbauer study suggest that the transition of Fe3O4 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.

  20. Frictional coefficients of ion-implanted alumina against ion-implanted beta-titanium in the low load, low velocity, single pass regime.

    PubMed

    Kusy, R P; Tobin, E J; Whitley, J Q; Sioshansi, P

    1992-05-01

    The frictional coefficients were measured for four wire alloys against the flats of polycrystalline alumina cylinders using a low load, low velocity, single pass device. Ion-implantations of titanium into polycrystalline alumina flats and nitrogen into beta-titanium wires reduced the static and kinetic coefficients from 0.50 and 0.44 before implantation to 0.20 and 0.25 after implantation, respectively. These results are similar in magnitude to frictional coefficients for unimplanted, control couples of stainless steel, cobalt-chromium, and nickel titanium wires against polycrystalline alumina flats. For orthodontic applications, we conclude that more efficient and reproducible appliances can be engineered for tooth movement if ion-implantation is used to reduce the abrasion of beta-titanium by polycrystalline alumina. PMID:1521704

  1. Blistering and cracking of LiTaO3 single crystal under helium ion implantation

    NASA Astrophysics Data System (ADS)

    Ma, Changdong; Lu, Fei; Ma, Yujie

    2015-03-01

    Blistering and cracking in LiTaO3 surface are investigated after 200-keV helium ion implantation and subsequent post-implantation annealing. Rutherford backscattering/channeling is used to examine the lattice damage caused by ion implantation. Blistering is observed through optical microscopy in a dynamic heating process. Atomic force microscopy and scanning electron microscopy measurements are used to detect the LiTaO3 surface morphology. Experimental results show that blistering and flaking are dependent on implantation fluence, beam current, and also annealing temperature. We speculate that the surface cracking of He+-implanted LiTaO3 results from the implantation-induced stress and compression.

  2. Comparison between conventional and plasma source ion-implanted femoral knee components

    NASA Astrophysics Data System (ADS)

    Chen, A.; Scheuer, J. T.; Ritter, C.; Alexander, R. B.; Conrad, J. R.

    1991-12-01

    Nitrogen ion implantation of Ti-6Al-4V knee joint femoral components was carried out by both plasma source ion implantation (PSII), a non-line of sight technique, and conventional beamline implantation. Implantation using the PSII process was performed on a flat sample as well as a 2×2 square array of components to demonstrate batch processing capability. The retained dose of the flat sample and at different locations on the implanted components was measured by a scanning auger microprobe (SAM). The variation in dose of the PSII treated component was found to be within the SAM error, while the dose at one location on the beamline implanted component was found to be significantly low. For the beamline case, the SAM results show good agreement with the PC profile computer simulation, which includes the angular dependence of sputtering.

  3. Ion implantation to reduce wear on polyethylene prosthetic devices. Rept. for Aug 89-Jan 91

    SciTech Connect

    Not Available

    1991-05-01

    Researchers studied the use of ion implantation to improve the wear performance of ultra high molecular weight polyethylene (UHMWPE). UHMWPE samples were implanted with high energy ions, tested for wear performance, and compared to unimplanted control samples. Surface friction and hardness measurements, Raman scattering, Rutherford backscattering (RBS), water contact angle, and film transfer tests were performed to characterize the surface property changes of implanted UHMWPE samples. Results indicated a 90% reduction in wear on implanted UHMWPE disks. Implantation increased surface microhardness and surface energy. The Raman spectrum revealed a diamond-like signature, indicting carbon bonds of a different nature than those found in unimplanted polyehtylene. Photographic analysis of pins used in wear testing revealed differences between implanted and unimplanted samples in the polyethylene film transferred in the initial stages of wear from the disk to the pin.

  4. Microstructure of Co-doped TiO₂ (110) Rutile by Ion Implantation

    SciTech Connect

    Wang, Chong M.; Shutthanandan, V.; Thevuthasan, Suntharampillai; Droubay, Timothy C.; Chambers, Scott A.

    2005-04-01

    Co-doped rutile TiO₂ was synthesized by injecting Co ions into single crystal rutile TiO₂ using high energy ion implantation. Microstructures of the implanted specimens were studied in detail using high-resolution transmission electron microscopy (HRTEM), energy dispersive x-ray spectroscopy (EDS), electron diffraction, and HRTEM image simulations. The spatial distribution and conglomeration behavior of the implanted Co ions, as well as the point defect distributions induced by ion implantation, show strong dependences on implantation conditions. Uniform distribution of Co ions in the rutile TiO₂ lattice was obtained by implanting at 1075 K with a Co ion fluence of 1.25x10¹⁶ Co/cm². Implanting at 875 K leads to the formation of Co metal clusters. The precipitated Co metal clusters and surrounding TiO₂ matrix exhibit the orientation relationships Co<110>//TiO₂[001] and Co{111}//TiO₂(110). A structural model representing the interface between Co metal clusters and TiO₂ is developed based on HRTEM imaging and image simulations.

  5. Microstructure of Co-doped TiO{sub 2}(110) rutile by ion implantation

    SciTech Connect

    Wang, C.M.; Shutthanandan, V.; Thevuthasan, S.; Droubay, T.; Chambers, S.A.

    2005-04-01

    Co-doped rutile TiO{sub 2} was synthesized by injecting Co ions into single crystal rutile TiO{sub 2} using high energy ion implantation. Microstructures of the implanted specimens were studied in detail using high-resolution transmission electron microscopy (HRTEM), energy dispersive x-ray spectroscopy, electron diffraction, and HRTEM image simulations. The spatial distribution and conglomeration behavior of the implanted Co ions, as well as the point defect distributions induced by ion implantation, show strong dependences on implantation conditions. Uniform distribution of Co ions in the rutile TiO{sub 2} lattice was obtained by implanting at 1075 K with a Co ion fluence of 1.25x10{sup 16} Co/cm{sup 2}. Implanting at 875 K leads to the formation of Co metal clusters. The precipitated Co metal clusters and surrounding TiO{sub 2} matrix exhibit the orientation relationships Co<110> parallel TiO{sub 2}[001] and Co{l_brace}111{r_brace} parallel TiO{sub 2}(110). A structural model representing the interface between Co metal clusters and TiO{sub 2} is developed based on HRTEM imaging and image simulations.

  6. 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.

  7. Characterization of Surface Properties and Microstructure of PVD-TiN Films Using Mevva Ion Implantation

    NASA Astrophysics Data System (ADS)

    Yang, J. H.; Cheng, M. F.; Luo, X. D.; Zhang, T. H.

    The PVD-TiN film was implanted with titanium ions and the improvement in surface wear resistance was investigated. Ti ion implantation was done using a metal vapor vacuum arc (MEVVA) ion source with an implantation dose of 2 × 1016 ions/cm2 and at an extraction voltage of 48 kV. The wear characteristics of the implanted zone was measured and compared to the performance of the unimplanted zone by a pin-on-disc apparatus and an optical interference microscope. The structure of the implanted zone and unimplanted one was observed by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). A dynamic TRIM called TRIDYN was used to calculate the concentration depth profile of implanted Ti in TiN to investigate the profile of multi-charge state ions. The results showed that the improved wear resistance of the TiN film was mainly due to the presence of nano-order TiN crystal grains after Ti ion implantation.

  8. The Void Effect of Mevva W Ion Implantation on the Tribological Properties of H13 Steel

    NASA Astrophysics Data System (ADS)

    Yang, Jianhua; Zhang, Tonghe

    H13 steel samples were implanted with tungsten using a metal vapor vacuum arc (MEVVA) ion source, with an implantation dose of 1×1017 cm-2, an extraction acceleration of 30 kV and pulsed ion beam fluxes of between 0.3 mA·cm-2 and 6 mA·cm-2. The surface mechanical properties and microstructure for the W-implanted samples was characterized by the Rutherford backscattering spectroscope (RBS) and a high voltage electron microscope (HVEM). Experimental results of wear and hardness indicated that the hardness and wear of H13 steel increased when the voids were produced by tungsten ion implantation with a high pulsed current density. Forming causes for voids and their influence on the tungsten concentration depth profile in the implanted H13 steel and the surface mechanical properties were discussed in terms of spike theory.

  9. Ion implantation processing for high-speed GaAs JFETs

    SciTech Connect

    Zolper, J.C.; Baca, A.G.; Sherwin, M.E.; Shul, R.J.

    1995-07-01

    GaAs Junction Field Effect Transistors (JFETs) offer a higher gate turn-on voltage, resulting in a better noise margin and reduced power dissipation, than the more widely employed GaAs MESFET. The primary reason the JFET has not been more widely used is the speed penalty associated with the gate/channel junction and corresponding gate length broadening. We present the ion implantation processes used for a self-aligned, all ion-implanted, GaAs JFET that minimizes the speed penalty for the JFET while maintaining the advantageous higher gate turn-on voltage. Process characterization of the p{sub +}-gate implant done with either Mg, Zn, or Cd along with the co-implantation of P is presented. In addition, a novel backside channel confinement technology employing ion-implanted carbon is discussed. Complete JFET device results are reported.

  10. Heavy-ion sources: The Star, or the Cinderella, of the ion-implantation firmament? (invited)

    NASA Astrophysics Data System (ADS)

    Freeman, Harry

    2000-02-01

    The Star, because of the invaluable contribution which the heavy-ion source has already made to the successful development of semiconductor implantation. And the Star, too, because it is evident that the key characteristics of such sources, which are now used on a quite routine industrial basis—their reliability, their ease of operation and, above all, their extraordinary versatility—have still not been fully exploited. This ensures that there is still scope, at least in the short term, for further optimization, which will go some way to meet the increasingly stringent industrial doping requirements. The Cinderella, because of my belief that these heavy-ion sources have now contributed to the successful operation of ion implanters so well, and for so long, that their present level of performance is mistakenly taken for granted. The result has been a paucity of meaningful research and development. Despite this, in this article I aim to show that, like Cinderella, who was so neglected that her true merit was long overlooked, there is the prospect too of achieving the significantly larger improvements in beam quality which the semiconductor industry will eventually be seeking.

  11. Ion Implantation Angle Variation to Device Performance and the Control in Production

    SciTech Connect

    Zhao, Z.Y.; Hendrix, D.; Wu, L.Y.; Cusson, B.K.

    2003-08-26

    As the device features get smaller and aspect ratios of photoresist openings get steeper, shadowing effect has more impact on the performance of devices. Many of the traditional 7 deg. tilt implants have progressed to 0 deg. implants. But shadowing may still occur if the tilt angle deviates from normal direction. Some implants, such as halo implants, demand even more stringent angle control to reduce device performance variation. The demand for implant angle control and monitoring thus becomes more obvious and important. However, statistical process control (SPC) cannot be done on shadowing effect without special test structures. Channeling, on the other hand, provides good sensitivity in regard to implant angle changes. It is the authors' intention to introduce channeling implant in different channels to monitor the implant angle variation. The incoming <100> silicon wafers have a cut-angle spec of +/- 1.0 deg. This poses a difficulty if one wants to control the implant angle's accuracy within +/- 0.5 deg. Other measures have to be taken to ensure the consistency of test wafers and to have prompt diagnosis feedback when needed. This paper will discuss the effect of implant tilt angle on device parameters and how to control the angle variation in production. Correlations of implant tilt angle variation to ThermaWave, sheet resistance (Rs), Secondary Ion Mass Spectrometry (SIMS) and device parameters will be covered with certain implant conditions.

  12. Ion Implantation Angle Variation to Device Performance and the Control in Production

    NASA Astrophysics Data System (ADS)

    Zhao, Z. Y.; Hendrix, D.; Wu, L. Y.; Cusson, B. K.

    2003-08-01

    As the device features get smaller and aspect ratios of photoresist openings get steeper, shadowing effect has more impact on the performance of devices. Many of the traditional 7° tilt implants have progressed to 0° implants. But shadowing may still occur if the tilt angle deviates from normal direction. Some implants, such as halo implants, demand even more stringent angle control to reduce device performance variation. The demand for implant angle control and monitoring thus becomes more obvious and important. However, statistical process control (SPC) cannot be done on shadowing effect without special test structures. Channeling, on the other hand, provides good sensitivity in regard to implant angle changes. It is the authors' intention to introduce channeling implant in different channels to monitor the implant angle variation. The incoming <100> silicon wafers have a cut-angle spec of +/- 1.0°. This poses a difficulty if one wants to control the implant angle's accuracy within +/- 0.5°. Other measures have to be taken to ensure the consistency of test wafers and to have prompt diagnosis feedback when needed. This paper will discuss the effect of implant tilt angle on device parameters and how to control the angle variation in production. Correlations of implant tilt angle variation to ThermaWave™, sheet resistance (Rs), Secondary Ion Mass Spectrometry (SIMS) and device parameters will be covered with certain implant conditions.

  13. Low-cost ion implantation and annealing technology for solar cells

    NASA Technical Reports Server (NTRS)

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

    1980-01-01

    Ion implantation and thermal annealing techniques for processing junctions and back surface layers in solar cells are discussed. Standard 10 keV (31)p(+) junction implants and 25 keV (11)B(+) back surface implants in combination with three-step furnace annealing are used for processing a range of silicon materials and device structures. Cells with efficiencies up to 16.5% AM1 are being produced, and large-area terrestrial cells with implanted junctions and back fields being fabricated in pilot production exhibit average efficiencies in excess of 15% AM1. Thermal annealing methods for removal of the radiation damage caused by implantation should be replaced by transient processing techniques in future production. Design studies have been completed for solar cell processing implanters to support 10 MW/yr and 100 MW/yr production lines, and analyses indicate that implantation costs can be reduced to approximately 1 cent/watt.

  14. Mechanisms of Focused Ion Beam Implantation Damage and Recovery in Si

    NASA Astrophysics Data System (ADS)

    Balasubramanian, G. P. S.; Hull, R.

    2016-06-01

    The ion current density in focused ion beam (FIB) systems, 0.1-10 A cm-2, is at least three orders of magnitude greater than that in commercial broad ion beam implanters. This large difference in ion current density is expected to strongly affect the damage recovery dynamics. In this work, we study the ion implantation damage and recovery of Si(100) substrates implanted with 1 × 1012-5 × 1015 Si cm-2 fluences of 60-keV Si2+ at normal incidence in a mass-selecting FIB. Additionally, damage and recovery in different broad ion beam implants of 60-keV Si+ were studied for a comparison. For recovering implantation damage, specimens were annealed for different times at 730-900°C in an ultra-high purity nitrogen ambient, and for characterizing damage and recovery, Raman spectroscopy at wavelengths 405 nm and 514 nm was carried out. Raman measurements comprised of measurements of crystalline Si (c-Si) peak height of the peak at 520 cm-1, and the peak shift relative to that of un-implanted reference Si. Our measurements of structural damage—calculated from the attenuation in the c-Si peak heights for the implants relative to that of unimplanted Si(100)—indicates that the FIB implantations lead to a greater as-implanted damage but also typically lead to a better recovery than that for the commercial broad-area implants. The underlying mechanisms for these observations are discussed.

  15. Surface analytical studies of ion-implanted uni-directionally aligned silicon nitride for tribological applications

    NASA Astrophysics Data System (ADS)

    Nakamura, Naoki; Hirao, Kiyoshi; Yamauchi, Yukihiko

    2004-03-01

    Uni-directionally aligned silicon nitride, which exhibits both high strength and high toughness, was implanted with B +, N +, Si + and Ti + ions at a fluence of 2 × 10 17 ions/cm 2 and an energy of 200 keV. The effect of ion implantation on the surface structure of the uni-directionally aligned silicon nitride has been studied, in terms of surface analyses such as atomic force microscopy (AFM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectroscopy (SIMS) and X-ray absorption near edge structure (XANES). It was clarified that the ion-implanted layer was amorphized and the implantation profile showed good agreement with that estimated from a TRIM simulation. It was found that BN and TiN were formed in B +- and Ti +-implanted Si 3N 4, respectively. There was a slight difference in ion implantation depth among different structures of Si 3N 4, considered to be due to differences in ion channeling.

  16. Investigation of Mn-implanted n-Si by low-energy ion beam deposition

    NASA Astrophysics Data System (ADS)

    Liu, Lifeng; Chen, Nuofu; Song, Shulin; Yin, Zhigang; Yang, Fei; Chai, Chunlin; Yang, Shaoyan; Liu, Zhikai

    2005-01-01

    Mn ions were implanted to n-type Si(0 0 1) single crystal by low-energy ion beam deposition technique with an energy of 1000 eV and a dose of 7.5×10 17 cm -2. The samples were held at room temperature and at 300 °C during implantation. Auger electron spectroscopy depth profiles of samples indicate that the Mn ions reach deeper in the sample implanted at 300 °C than in the sample implanted at room temperature. X-ray diffraction measurements show that the structure of the sample implanted at room temperature is amorphous while that of the sample implanted at 300 °C is crystallized. There are no new phases found except silicon both in the two samples. Atomic force microscopy images of samples indicate that the sample implanted at 300 °C has island-like humps that cover the sample surface while there is no such kind of characteristic in the sample implanted at room temperature. The magnetic properties of samples were investigated by alternating gradient magnetometer (AGM). The sample implanted at 300 °C shows ferromagnetic behavior at room temperature.

  17. Determination of migration of ion-implanted Ar and Zn in silica by backscattering spectrometry

    NASA Astrophysics Data System (ADS)

    Szilágyi, E.; Bányász, I.; Kótai, E.; Németh, A.; Major, C.; Fried, M.; Battistig, G.

    2015-03-01

    It is well known that the refractive indices of lots of materials can be modified by ion implantation, which is important for waveguide fabrication. In this work the effect of Ar and Zn ion implantation on silica layers was investigated by Rutherford Backscattering Spectrometry (RBS) and Spectroscopic Ellipsometry (SE). Silica layers produced by chemical vapour deposition technique on single crystal silicon wafers were implanted by Ar and Zn ions with a fluence of 1-2 ×1016 Ar/cm2 and 2.5 ×1016 Zn/cm2, respectively. The refractive indices of the implanted silica layers before and after annealing at 300°C and 600°C were determined by SE. The migration of the implanted element was studied by real-time RBS up to 500°C. It was found that the implanted Ar escapes from the sample at 300°C. Although the refractive indices of the Ar-implanted silica layers were increased compared to the as-grown samples, after the annealing this increase in the refractive indices vanished. In case of the Zn-implanted silica layer both the distribution of the Zn and the change in the refractive indices were found to be stable. Zn implantation seems to be an ideal choice for producing waveguides.

  18. Mechanical characterization of several ion-implanted alloys: nanoindentation testing, wear testing and finite element modeling

    NASA Astrophysics Data System (ADS)

    Bourcier, R. J.; Follstaedt, D. M.; Dugger, M. T.; Myers, S. M.

    1991-07-01

    The influence of ion implantation on the mechanical properties of metal alloys has been examined using a variety of experimental and numerical techniques. Ultralow load indentation testing and finite element modeling has been used for the aluminum/oxygen to extract fundamental mechanical properties. Aluminum implanted with 20 at.% O exhibits extraordinary strength, as high as 3300 MPa. The degree of strengthening expected for this Al(O) alloy on the basis of the observed microstructure of fine (1.5-3.5 nm) oxide precipitates was estimated using several micromechanical models, and the results agree with our experimental findings. Pin-on-disk tribological characterization of aluminum implanted with 10 at.% oxygen revealed that the ion-beam treatment reduced the average friction coefficient from greater than 1.0 (for pure Al) to approximately 0.25 (for Al(O)). Large-amplitude stick-slip oscillations, which occur within the first two cycles for pure aluminum, were postponed to 30-50 cycles for the ion-implanted material. Two stainless steels which have been amorphized by implantation, 304 implanted with C and 440C implanted with Ti + C, show measurable hardening with implantation, of the order of 40 and 15%, respectively. In addition, nanoindentation within pin-on-disk wear tracks on 440C reveals that the mechanical state of the extensively deformed implanted layer is apparently unchanged from its initial state.

  19. Ion-Implanted Silicon X-Ray Calorimeters: Present and Future

    NASA Astrophysics Data System (ADS)

    Kelley, R. L.; Allen, C. A.; Galeazzi, M.; Kilbourne, C. A.; McCammon, D.; Porter, F. S.; Szymkowiak, A. E.

    2008-04-01

    We now have about 25 years of experience with X-ray calorimeters based on doped semiconductor thermometers. Ion-implanted Si arrays have been used in astrophysics and laboratory atomic physics. The device properties and characteristics are sufficiently well understood to allow optimized designs for a wide variety of applications over the 0.1 100 keV range. With new absorber materials, approaches for absorber attachment and compact, low thermal conductance JFET arrays, it should be possible to advance this technology from the 36 pixel arrays of today to arrays that are about an order of magnitude larger, and with significantly improved energy resolution. These would enable new capabilities on instruments being considered now for missions that may fly in about five years.

  20. 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.

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

    SciTech Connect

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

    1995-10-01

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

  2. Temperature Activated Diffusion of Radicals through Ion Implanted Polymers.

    PubMed

    Wakelin, Edgar A; Davies, Michael J; Bilek, Marcela M M; McKenzie, David R

    2015-12-01

    Plasma immersion ion implantation (PIII) is a promising technique for immobilizing biomolecules on the surface of polymers. Radicals generated in a subsurface layer by PIII treatment diffuse throughout the substrate, forming covalent bonds to molecules when they reach the surface. Understanding and controlling the diffusion of radicals through this layer will enable efficient optimization of this technique. We develop a model based on site to site diffusion according to Fick's second law with temperature activation according to the Arrhenius relation. Using our model, the Arrhenius exponential prefactor (for barrierless diffusion), D0, and activation energy, EA, for a radical to diffuse from one position to another are found to be 3.11 × 10(-17) m(2) s(-1) and 0.31 eV, respectively. The model fits experimental data with a high degree of accuracy and allows for accurate prediction of radical diffusion to the surface. The model makes useful predictions for the lifetime over which the surface is sufficiently active to covalently immobilize biomolecules and it can be used to determine radical fluence during biomolecule incubation for a range of storage and incubation temperatures so facilitating selection of the most appropriate parameters. PMID:26562064

  3. Nissin Ion Doping System--H{sub 2}{sup +} Implantation for Silicon Layer Exfoliation

    SciTech Connect

    Cherekdjian, S.; Maschmeyer, R. O.; Cites, J.; Tatemichi, J.; Inouchi, Y.; Onoda, M.; Orihira, K.; Matsumoto, T.; Konishi, M.; Naito, M.

    2011-01-07

    A Nissin iG4 ion doping system (termed iG4) utilizes broad beam technology to implant GEN 4 sheets of glass for LCD production. The mechanical scanned end-station with robotic handling for GEN 4 glass substrates was redesigned, and a new end-station was built to handle rectangular silicon tiles (23x18 cm). A three sub-system modular risk reduction process was used to test production solutions, and maximize the success of transferring the R and D implant recipes developed on a standard focused beam ion implanter to the Nissin broad beam iG4 solution. The silicon tile end-station including the implant scanning system was tested for reliability and durability. The end-station handled rectangular silicon tiles reliably without detrimental edge chipping or silicon breakage. The ion optics was demonstrated to successfully provide stable hydrogen ions for the Corning registered silicon on glass layer transfer process. This layer transfer process is very susceptible and sensitive to the implant processing temperature. The temperature excursions during implant processing for the iG4 exfoliation process were found to be in line with the R and D focused ion beam system. This data confirmed the system production-readiness in providing an efficient solution for the high volume production of hydrogen implanted silicon rectangular tiles.

  4. Immobilization of extracellular matrix on polymeric materials by carbon-negative-ion implantation

    NASA Astrophysics Data System (ADS)

    Tsuji, Hiroshi; Sommani, Piyanuch; Muto, Takashi; Utagawa, Yoshiyuki; Sakai, Shun; Sato, Hiroko; Gotoh, Yasuhito; Ishikawa, Junzo

    2005-08-01

    Effects of ion implantation into polystyrene (PS), silicone rubber (SR) and poly-L-lactic acid (PLA) have been investigated for immobilization of extracellular matrix. Carbon negative ions were implanted into PS and SR sheets at various energies between 5-30 keV and various doses between 1.0 × 1014-1.0 × 1016 ions/cm2. Contact angles of pure water on C-implanted surfaces of PS and SR were decreased as increase in ion energy and in dose due to formation of functional groups such as OH and C-O. Selective attachment of nerve cells was observed on C-implanted them at 10 keV and 3 × 1015 ions/cm2 after in vitro cell culture of nerve cells of PC-12 h. Neurite outgrowth also extended over the implanted area. After dipping in a serum medium and in a fibronectin solution for 2 h, the detection of N 1s electrons by X-ray induced photoelectron spectroscopic (XPS) revealed a significant distinction of protein adhesion on the implanted area. Thus, immobilization of proteins on surface is used for considering the selective cell-attachment. For PLA, the selective attachment of cells and protein depended on the implantation conditions.

  5. 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.

  6. Direction-dependent RBS channelling studies in ion implanted LiNbO3

    NASA Astrophysics Data System (ADS)

    Wendler, E.; Becker, G.; Rensberg, J.; Schmidt, E.; Wolf, S.; Wesch, W.

    2016-07-01

    Damage formation in ion implanted LiNbO3 was studied by Rutherford backscattering spectrometry (RBS) along various directions of the LiNbO3 crystal. From the results obtained it can be unambiguously concluded that Nb atoms being displaced during ion implantation preferably occupy the free octahedron sites of the LiNbO3 lattice structure and most likely also form NbLi antisite defects.

  7. Neutron activation analysis for reference determination of the implantation dose of cobalt ions

    SciTech Connect

    Garten, R.P.H.; Bubert, H.; Palmetshofer, L.

    1992-05-15

    The authors prepared depth profilling reference materials by cobalt ion implantation at an ion energy of 300 keV into n-type silicon. The implanted Co dose was then determined by instrumental neutron activation analysis (INAA) giving an analytical dynamic range of almost 5 decades and uncertainty of 1.5%. This form of analysis allows sources of error (beam spreading, misalignment) to be corrected. 70 refs., 3 tabs.

  8. Optical absorption in ion-implanted lead lanthanum zirconate titanate ceramics

    SciTech Connect

    Seager, C.H.; Land, C.E.

    1984-08-15

    Optical absorption measurements have been performed on unmodified and on ion-implanted lead lanthanum zirconate titanate ceramics using the photothermal deflection spectroscopy technique. Bulk absorption coefficients depend on the average grain size of the material while the absorption associated with the ion-damaged layers does not. The damage-induced surface absorptance correlates well with the photosensitivity observed in implanted PLZT devices, supporting earlier models for the enhanced imaging efficiency of the materials.

  9. INSTRUMENTS AND METHODS OF INVESTIGATION: Impurity ion implantation into silicon single crystals: efficiency and radiation damage

    NASA Astrophysics Data System (ADS)

    Vavilov, V. S.; Chelyadinskii, Aleksei R.

    1995-03-01

    The ion implantation method is analysed from the point of view of its efficiency as a technique for doping silicon with donor and acceptor impurities, for synthesising silicon-based compounds and for producing gettering layers and optoelectronic structures. The introduction, agglomeration, and annealing of radiation-produced defects in ion-implanted silicon are considered. The role of interstitial defects in radiation-related defect formation is estimated. Mechanisms of athermal migration of silicon atoms in the silicon lattice are analysed.

  10. Tunnel oxide passivated contacts formed by ion implantation for applications in silicon solar cells

    NASA Astrophysics Data System (ADS)

    Reichel, Christian; Feldmann, Frank; Müller, Ralph; Reedy, Robert C.; Lee, Benjamin G.; Young, David L.; Stradins, Paul; Hermle, Martin; Glunz, Stefan W.

    2015-11-01

    Passivated contacts (poly-Si/SiOx/c-Si) doped by shallow ion implantation are an appealing technology for high efficiency silicon solar cells, especially for interdigitated back contact (IBC) solar cells where a masked ion implantation facilitates their fabrication. This paper presents a study on tunnel oxide passivated contacts formed by low-energy ion implantation into amorphous silicon (a-Si) layers and examines the influence of the ion species (P, B, or BF2), the ion implantation dose (5 × 1014 cm-2 to 1 × 1016 cm-2), and the subsequent high-temperature anneal (800 °C or 900 °C) on the passivation quality and junction characteristics using double-sided contacted silicon solar cells. Excellent passivation quality is achieved for n-type passivated contacts by P implantations into either intrinsic (undoped) or in-situ B-doped a-Si layers with implied open-circuit voltages (iVoc) of 725 and 720 mV, respectively. For p-type passivated contacts, BF2 implantations into intrinsic a-Si yield well passivated contacts and allow for iVoc of 690 mV, whereas implanted B gives poor passivation with iVoc of only 640 mV. While solar cells featuring in-situ B-doped selective hole contacts and selective electron contacts with P implanted into intrinsic a-Si layers achieved Voc of 690 mV and fill factor (FF) of 79.1%, selective hole contacts realized by BF2 implantation into intrinsic a-Si suffer from drastically reduced FF which is caused by a non-Ohmic Schottky contact. Finally, implanting P into in-situ B-doped a-Si layers for the purpose of overcompensation (counterdoping) allowed for solar cells with Voc of 680 mV and FF of 80.4%, providing a simplified and promising fabrication process for IBC solar cells featuring passivated contacts.

  11. 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.

  12. 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.

  13. Effect of implanted species on thermal evolution of ion-induced defects in ZnO

    SciTech Connect

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

    2014-02-21

    Implanted atoms can affect the evolution of ion-induced defects in radiation hard materials exhibiting a high dynamic annealing and these processes are poorly understood. Here, we study the thermal evolution of structural defects in wurtzite ZnO samples implanted at room temperature with a wide range of ion species (from {sup 11}B to {sup 209}Bi) to ion doses up to 2 × 10{sup 16} cm{sup −2}. The structural disorder was characterized by a combination of Rutherford backscattering spectrometry, nuclear reaction analysis, and transmission electron microscopy, while secondary ion mass spectrometry was used to monitor the behavior of both the implanted elements and residual impurities, such as Li. The results show that the damage formation and its thermal evolution strongly depend on the ion species. In particular, for F implanted samples, a strong out-diffusion of the implanted ions results in an efficient crystal recovery already at 600 °C, while co-implantation with B (via BF{sub 2}) ions suppresses both the F out-diffusion and the lattice recovery at such low temperatures. The damage produced by heavy ions (such as Cd, Au, and Bi) exhibits a two-stage annealing behavior where efficient removal of point defects and small defect clusters occurs at temperatures ∼500 °C, while the second stage is characterized by a gradual and partial annealing of extended defects. These defects can persist even after treatment at 900 °C. In contrast, the defects produced by light and medium mass ions (O, B, and Zn) exhibit a more gradual annealing with increasing temperature without distinct stages. In addition, effects of the implanted species may lead to a nontrivial defect evolution during the annealing, with N, Ag, and Er as prime examples. In general, the obtained results are interpreted in terms of formation of different dopant-defect complexes and their thermal stability.

  14. Effect of implanted species on thermal evolution of ion-induced defects in ZnO

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

    Implanted atoms can affect the evolution of ion-induced defects in radiation hard materials exhibiting a high dynamic annealing and these processes are poorly understood. Here, we study the thermal evolution of structural defects in wurtzite ZnO samples implanted at room temperature with a wide range of ion species (from 11B to 209Bi) to ion doses up to 2 × 1016 cm-2. The structural disorder was characterized by a combination of Rutherford backscattering spectrometry, nuclear reaction analysis, and transmission electron microscopy, while secondary ion mass spectrometry was used to monitor the behavior of both the implanted elements and residual impurities, such as Li. The results show that the damage formation and its thermal evolution strongly depend on the ion species. In particular, for F implanted samples, a strong out-diffusion of the implanted ions results in an efficient crystal recovery already at 600 °C, while co-implantation with B (via BF2) ions suppresses both the F out-diffusion and the lattice recovery at such low temperatures. The damage produced by heavy ions (such as Cd, Au, and Bi) exhibits a two-stage annealing behavior where efficient removal of point defects and small defect clusters occurs at temperatures ˜500 °C, while the second stage is characterized by a gradual and partial annealing of extended defects. These defects can persist even after treatment at 900 °C. In contrast, the defects produced by light and medium mass ions (O, B, and Zn) exhibit a more gradual annealing with increasing temperature without distinct stages. In addition, effects of the implanted species may lead to a nontrivial defect evolution during the annealing, with N, Ag, and Er as prime examples. In general, the obtained results are interpreted in terms of formation of different dopant-defect complexes and their thermal stability.

  15. A feasibility study of ion implantation techniques for mass spectrometer calibration

    NASA Technical Reports Server (NTRS)

    Koslin, M. E.; Krycuk, G. A.; Schatz, J. G., Jr.; White, F. A.; Wood, G. M.

    1978-01-01

    An experimental study was undertaken to examine the feasibility of using ion-implanted filaments doped with either an alkali metal or noble gas for in situ recalibration of onboard mass spectrometers during extended space missions. Implants of rubidium and krypton in rhenium ribbon filaments were subsequently tested in a bakeable 60 deg sector mass spectrometer operating in the static mode. Surface ionization and electron impact ion sources were both used, each yielding satisfactory results. The metallic implant with subsequent ionization provided a means of mass scale calibration and determination of system operating parameters, whereas the noble gas thermally desorbed into the system was more suited for partial pressure and sensitivity determinations.

  16. Improved corrosion resistance on biodegradable magnesium by zinc and aluminum ion implantation

    NASA Astrophysics Data System (ADS)

    Xu, Ruizhen; Yang, Xiongbo; Suen, Kai Wong; Wu, Guosong; Li, Penghui; Chu, Paul K.

    2012-12-01

    Magnesium and its alloys have promising applications as biodegradable materials, and plasma ion implantation can enhance the corrosion resistance by modifying the surface composition. In this study, suitable amounts of zinc and aluminum are plasma-implanted into pure magnesium. The surface composition, phases, and chemical states are determined, and electrochemical tests and electrochemical impedance spectroscopy (EIS) are conducted to investigate the surface corrosion behavior and elucidate the mechanism. The corrosion resistance enhancement after ion implantation is believed to stem from the more compact oxide film composed of magnesium oxide and aluminum oxide as well as the appearance of the β-Mg17Al12 phase.

  17. Photosensitivity enhancement by H- and He-ion implantation in lead lanthanum zirconate titanate ceramics

    SciTech Connect

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

    1980-07-01

    H- and He-ion implantation has been used to increase the photoferroelectric image storage sensitivity of lead lanthanum zirconium titanate ceramics by factors of approx.10 and approx.30, respectively. The increased photosensitivity can be attributed primarily to implantation-produced disorder, which increases the efficiency of carrier photoexcitation and trapping and reduces the exposure energy required to establish nonvolatile space-charge fields. Implantation-induced disorder may also contribute to a substantial increase in photoconductivity in the ion-damaged near-surface region.

  18. Transition metal swift heavy ion implantation on 4H-SiC

    NASA Astrophysics Data System (ADS)

    Ali, A. Ashraf; Kumar, J.; Ramakrishnan, V.; Asokan, K.

    2016-03-01

    This work reports on the realization of Quantum Ring (QR) and Quantum Dot (QD) like structures on 4H-SiC through SHI implantation and on their Raman studies. 4H-SiC is SHI implanted with Transition Metal (TM) Ni ion at different fluences. It is observed that a vibrational mode emerges as the result of Ni ion implantation. The E2 (TO) and the A1 (LO) are suppressed as the fluence increases. In this paper Raman and AFM studies have been performed at room temperature and the queer anomalies are addressed so new devices can be fabricated.

  19. Method of making an ion-implanted planar-buried-heterostructure diode laser

    DOEpatents

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

    1992-01-01

    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 lever 14 and an n-type compositionally graded Group III-V cladding layer 16. The laser 10 includes an iion 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.

  20. Ion implantation processing of III-V strained-layer semiconductors

    SciTech Connect

    Myers, D.R.

    1987-01-01

    Ion implantation has had a strong impact on the development of III-V strained-layer semiconductor (SLS) materials and device technologies. Implantation studies have helped delineate the present understanding of strained-layer stability and metastability limits. Resulting ion beam technologies have led to improvements in a variety of SLS discrete devices, including optoelectronic emitters, photodetectors, and field-effect transistors. Both SLS stability criteria and implanted SLS devices are reviewed with respect to future applications in optoelectronics. 36 refs., 2 figs.

  1. Determination of Na acceptor level in Na+ ion-implanted ZnO single crystal

    NASA Astrophysics Data System (ADS)

    Wang, Zheng; Liu, Huibin; He, Haiping; Huang, Jingyun; Chen, Lingxiang; Ye, Zhizhen

    2015-03-01

    Ion implantation was used to dope Na acceptor into ZnO single crystals. With three mixed implantation energies, uniform depth distribution of Na ion in the surface region (~300 nm) of ZnO bulk crystals is achieved. Via post-implantation annealing, a donor-acceptor pair recombination band is identified in the low-temperature photoluminescence spectra, from which the energy level of Na-related acceptor in single crystalline ZnO is estimated to be 300 meV. A p-n junction based on this ZnO-Na layer shows rectifying characteristics, confirming the p-type conductivity.

  2. In Situ TEM Concurrent and Successive Au Self-Ion Irradiation and He Implantation

    SciTech Connect

    Chisholm, Claire; Hattar, K; Minor, Andrew

    2014-01-01

    The development of advanced computational methods used for predicting performance lifetimes of materials exposed to harsh radiation environments are highly dependent on fundamental understanding of solid-radiation interactions that occur within metal components. In this work, we present successive and concurrent in situ TEM dual-beam self-ion irradiation of 2.8MeV Au4+ and implantation of 10 keV He1+, utilizing a new facility at Sandia National Laboratories. These experiments, using a model material system, provide direct real-time insight into initial interactions of displacement damage and fission products that simulate damage from neutron exposure. In successive irradiation, extensive dislocation loop and stacking fault tetrahedra damage was formed and could be associated with individual ion strikes, but no evidence of cavity formation was observed. In contrast, concurrent irradiation to the same dose resulted in the onset of cavity formation at the site of a heavy-ion strike. This direct real-time observation provides insight into the complex interplay between the helium and vacancy dynamics.

  3. An Auger Sputter Profiling Study of Nitrogen and Oxygen Ion Implantations in Two Titanium Alloys

    SciTech Connect

    Barton, B. D., Pope, L. E., Wittberg, T. N.

    1989-07-31

    Samples of two titanium alloys, Ti-6A1-4V and Ti-15V-3Cr-3Sn-3A1, were ion implanted with a combination of nitrogen (N+) and oxygen (O+). For each alloy, implantation parameters were chosen to give implanted nitrogen concentrations of approximately 10 or 50 atomic percent, from a depth of 100 nanometers to a depth of 400 nanometers. In all but one case, dual energy (200 keV and 90 keV) implantations of nitrogen were used to give a relatively uniform nitrogen concentration to a depth of 300 nanometers. In each case, oxygen was implanted at 35 keV, following the nitrogen implantation, to give an oxygen-enriched region near the surface. The implanted samples were then examined by Auger electron spectroscopy (AES) combined with argon ion sputtering. In order to determine the stoichiometry of the nitrogen implanted regions, it was necessary to determine the N (KVV) contribution to the overlapping N (KVV) and Ti (LMM) Auger transitions. It was also necessary to correct for the ion-bombardment-induced compositional changes which have been described in an earlier study of titanium nitride thin films. The corrected AES depth profiles were in good agreement with theoretical predictions.

  4. Microstructure and mechanical properties of Fe alloys ion implanted with Ti and N

    NASA Astrophysics Data System (ADS)

    Folistaedt, D. M.; Knapp, J. A.; Pope, L. E.; Picraux, S. T.

    1985-10-01

    The microstructure resulting when Ti and N are both ion-implanted into pure Fe at room temperature has been examined with ion beam analysis, transmission electron microscopy, and electron energy loss spectroscopy. Precipitates of TiN form within the bcc Fe matrix, in contrast to the amorphous phase which forms when Ti and C are both implanted. For comparison, the microstructure resulting when N alone is implanted into Fe was also examined, and Fe 2N precipitates were observed within the Fe matrix. The surface mechanical properties of 15-5 PH steel which was implanted with both Ti and N were examined with pin-on-disc testing, and the results were interpreted in terms of the microstructures observed in Fe. The modifications produced by Ti + N implantation are the same as observed with other treatments producing hard nitrides or carbides within the iron-based matrix: reduced wear is observed, but not reduced friction.

  5. Corrosion resistance and antithrombogenic behavior of La and Nd ion implanted stainless steels

    SciTech Connect

    Jing, F. J.; Jin, F. Y.; Liu, Y. W.; Wan, G. J.; Liu, X. M.; Zhao, X. B.; Fu, R. K. Y.; Leng, Y. X.; Huang, N.; Chu, Paul K.

    2006-09-15

    Lanthanide ions such as lanthanum (La) and neodymium (Nd) were implanted into 316 stainless steel samples using metal vapor vacuum arc to improve the surface corrosion resistance and antithrombogenic properties. X-ray photoelectron spectroscopy shows that lanthanum and neodymium exist in the +3 oxidation state in the surface layer. The corrosion properties of the implanted and untreated control samples were investigated utilizing electrochemical tests and our results show that La and Nd implantations enhance the surface corrosion resistance. In vitro activated partial thromboplastin time (APTT) tests were used to evaluate the antithrombogenic properties. The APTT time of the implanted samples was observed to be prolonged compared to that of the unimplanted stainless steel control. La and Nd ion implantations can be used to improve the surface corrosion resistance and biomedical properties of 316 stainless steels.

  6. Non-mass-analyzed ion implantation from a solid phosphorus source

    NASA Technical Reports Server (NTRS)

    Spitzer, M. B.; Bunker, S. N.

    1982-01-01

    A phosphorus ion beam, extracted from a Freeman ion source charged with elemental phosphorus, has been investigated for use in solar cell fabrication. Mass spectroscopy of the beam indicates the absence of both minority-carrier lifetime degrading impurities and hydrogen. The ion beam, without mass analysis, was used for ion implantation of solar cells, and performance for all cells was found to be equivalent to mass-analyzed controls.

  7. Synergistic effects of iodine and silver ions co-implanted in 6H-SiC

    NASA Astrophysics Data System (ADS)

    Kuhudzai, R. J.; Malherbe, J. B.; Hlatshwayo, T. T.; van der Berg, N. G.; Devaraj, A.; Zhu, Z.; Nandasiri, M.

    2015-12-01

    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 behaviour 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 °C for 30 h 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.

  8. 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.

  9. X-ray rocking curve analysis of ion implanted mercury cadmium telluride

    NASA Astrophysics Data System (ADS)

    Williams, B. L.; Robinson, H. G.; Helms, C. R.; Zhu, N.

    1997-06-01

    Junction formation by ion implantation is a critical step in producing high quality infrared focal plane arrays in mercury cadmium telluride (MCT). We have analyzed the structural properties of MCT implanted with B at doses of 1014 and 1015 cm-2 using double and triple crystal x-ray diffraction (DCD and TCD) to monitor the disorder and strain of the implanted region as a function of processing conditions. TCD (333) reflections show that a distinct tensile peak is produced by the high dose implant while the low dose implant shows only a low angle shoulder on the substrate peak. A preliminary association of the low angle shoulder with point defects has been made since no extended defects have been observed in the low dose range. For the high dose implant, extended defect formation has been reported and may be responsible for the tensile peak. After annealing, the low angle shoulder on the low dose implant has disappeared, while the high dose implant exhibits an increase in the tensile strain from 6.5 × 10-4 to 9.3 × 10-4 after 24 h of annealing and then decreases in tensile strain to 7.3 × 10-4 after 48 h of annealing. It is believed the changes in strain are associated with the Oswald ripening and dissolution of extended defects, which has been observed during annealing of ion implanted Si.

  10. 2D-ACAR Studies on Swift Heavy Ion Si-Implanted GaAs

    NASA Astrophysics Data System (ADS)

    Sivaji, K.; Selvakumar, S.

    Material properties modification by high energy heavy ion implantation is a prospective technology leading to many device fabrications. This technique induces defects and hence the physical properties of the materials are modified. The effects of swift heavy ion implantation induced defects by 120 MeV 28+Si ion implantation and doping in SI-GaAs are presented from the electron momentum distribution (EMD) of vacancy-type defects studied by two-dimensional angular correlation of annihilation radiation (2D-ACAR). The positron trapping due to the influence of high-energy Si- implantation in GaAs (n-type) is compared with the corresponding spectra of SI- GaAs and with Si-doped (n-type) GaAs. The EMD of the implanted sample shows a distinct increased isotropic distribution with a characteristic transform of its structure as evident from the low momentum region compared to the pristine sample. The characteristics of defects created by Si doping and by 120 MeV 28+Si ion implantation of undoped semi-insulating (SI) GaAS are discussed. These results indicate the nature of positron trapping in open volume defects such as vacancy clusters created by implantation.

  11. 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.

  12. Measurement of lattice damage caused by ion-implantation doping of semiconductors.

    NASA Technical Reports Server (NTRS)

    Hunsperger, R. G.; Wolf, E. D.; Shifrin, G. A.; Marsh, O. J.; Jamba, D. M.

    1971-01-01

    Discussion of two new techniques used to measure the lattice damage produced in GaAs by the implantation of 60 keV cadmium ions. In the first method, optical reflection spectra of the ion-implanted samples were measured in the wavelength range from 2000 to 4600 A. The decrease in reflectivity resulting from ion-implantation was used to determine the relative amount of lattice damage as a function of ion dose. The second technique employed the scanning electron microscope. Patterns very similar in appearance to Kikuchi electron diffraction patterns are obtained when the secondary and/or backscattered electron intensity is displayed as a function of the angle of incidence of the electron beam on a single crystal surface. The results of measurements made by both methods are compared with each other and with data obtained by the method of measuring lattice damage by Rutherford scattering of 1 MeV helium ions.

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

    PubMed Central

    Lu, Tao; Qiao, Yuqin; Liu, Xuanyong

    2012-01-01

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

  14. A Process for Topographically Selective Deposition on 3D Nanostructures by Ion Implantation.

    PubMed

    Kim, Woo-Hee; Minaye Hashemi, Fatemeh Sadat; Mackus, Adriaan J M; Singh, Joseph; Kim, Yeongin; Bobb-Semple, Dara; Fan, Yin; Kaufman-Osborn, Tobin; Godet, Ludovic; Bent, Stacey F

    2016-04-26

    Area-selective atomic layer deposition (AS-ALD) is attracting increasing interest because of its ability to enable both continued dimensional scaling and accurate pattern placement for next-generation nanoelectronics. Here we report a strategy for depositing material onto three-dimensional (3D) nanostructures with topographic selectivity using an ALD process with the aid of an ultrathin hydrophobic surface layer. Using ion implantation of fluorocarbons (CFx), a hydrophobic interfacial layer is formed, which in turn causes significant retardation of nucleation during ALD. We demonstrate the process for Pt ALD on both blanket and 2D patterned substrates. We extend the process to 3D structures, demonstrating that this method can achieve selective anisotropic deposition, selectively inhibiting Pt deposition on deactivated horizontal regions while ensuring that only vertical surfaces are decorated during ALD. The efficacy of the approach for metal oxide ALD also shows promise, though further optimization of the implantation conditions is required. The present work advances practical applications that require area-selective coating of surfaces in a variety of 3D nanostructures according to their topographical orientation. PMID:26950397

  15. Dynamics of Faceted Nanoparticles Formation in a Crystalline Matrix During Ion Implantation Processing.

    PubMed

    Li, Kun-Dar

    2016-02-01

    The faceted nanoparticle synthesized by ion implantation, such as Zn, Cu or Ag nanoparticles, is one of the promising materials for the next generation of optical devices. To understand and better control the manufacturing processes of ion implantation, a theoretical model is applied to investigate the formation and evolution of faceted nanoparticles under various experimental conditions of implantation processing. In this study, the mechanisms of the anisotropic interfacial energy and kinetics with different ion distributions are taken into consideration to demonstrate the role of the crystallographic symmetry, ion energy and temperature on the faceted nanoparticles formation in a crystalline matrix. As presented in the numerical results, the morphological shape of the nanoparticles is mainly affected by the crystallographic symmetry, while the distribution of the precipitates is principally determined by the ion energy. For the condition of high-temperature implantation, a high mobility of ions causes the characteristic length of nanostructures to increase and creates a coarsening morphology of nanoparticles. It is attributed to a longer diffusion distance during the nucleation and growth processes. This model can be widely used for the predictions of the nanostructures formation with various ion implantation processes. PMID:27433726

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

    SciTech Connect

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

    2010-06-06

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

  17. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

    In this paper, we show a way to control cobalt disilicide precipitation during Co ion implantation at high temperatures (650 °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.

  19. 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)

  20. Ring-type ESD damage caused by electrostatic chuck of ion implanter

    NASA Astrophysics Data System (ADS)

    King, Mingchu; Hsu, Chun-Keng; Fu, Chiang; Huang, Hsin-Chie; Yang, Shih-Yi; Liu, Yuan-Lung; Hsu, Kuo-chin

    1999-04-01

    Electrostatic discharge (ESD) due to electrostatic chuck (ESC) during ion implantation was observed in our fab. This defect could burn out the inter-layer dielectric and jeopardize the circuit performance. the yield impact on 0.35 micrometers product could be 40 percent. The defect distributed around the wafer edge and has a ring-type map. This defect occurred right after ESD implantation. The fringe field of the electrostatic chuck is the key reason why ring-type electrostatic discharge damage happened right after ion implantation. Our experimental result also showed that the junction characterization and surface conductivity will influence the probability of ESD damage caused by electrostatic chuck of ion implanter.

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

    SciTech Connect

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

    1997-10-01

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

  2. Voltage dependence of cluster size in carbon films using plasma immersion ion implantation

    NASA Astrophysics Data System (ADS)

    McKenzie, D. R.; Tarrant, R. N.; Bilek, M. M. M.; Pearce, G.; Marks, N. A.; McCulloch, D. G.; Lim, S. H. N.

    2003-05-01

    Carbon films were prepared using a cathodic arc with plasma immersion ion implantation (PIII). Using Raman spectroscopy to determine cluster size, a comparison is made between cluster sizes at high voltage and a low duty cycle of pulses with the cluster sizes produced at low voltage and a higher duty cycle. We find that for ion implantation in the range 2-20 kV, the cluster size depends more on implantation energy ( E) than implantation frequency ( f), unlike stress relief, which we have previously shown [M.M.M. Bilek, et al., IEEE Trans. in Plasma Sci., Proceedings 20th ISDEIV 1-5 July 2002, Tours, France, Cat. No. 02CH37331, IEEE, Piscataway, NJ, USA, p. 95] to be dependent on the product Ef. These differences are interpreted in terms of a model in which the ion impacts create thermal spikes.

  3. 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.

  4. Fabrication of highly homogeneous surface-enhanced Raman scattering substrates using Ag ion implantation

    NASA Astrophysics Data System (ADS)

    Li, Wenqing; Xiao, Xiangheng; Dai, Zhigao; Wu, Wei; Cheng, Li; Mei, Fei; Zhang, Xingang; Jiang, Changzhong

    2016-06-01

    In recent times, surface-enhanced Raman scattering (SERS) has attracted attention for its excellent potential application in chemical and biological detection. In this work, we demonstrate that a highly homogeneous SERS substrate can be realized by Ag ion implantation and the subsequent annealing process. Both the implantation and annealing parameters have been optimized for a high sensitivity SERS substrate. The SERS measurement indicates that a sample implanted by 20 kV Ag ions with a dosage of 3  ×  1016 ions cm‑2 exhibits the highest SERS activity. In addition, the SERS activity of the Ag-implanted substrates depends highly on the annealing temperature and time. Since none of the fabrication processes contain chemical reactions, our substrate is a clean system without any chemical residues.

  5. Modification of the optical spectra of glass by metal ion implantation

    NASA Astrophysics Data System (ADS)

    Yao, X. Y.; Fojas, P. B.; Brown, I. G.; Rubin, M. D.

    1993-06-01

    We have carried out some exploratory investigations of the effect of metal ion implantation on the optical transmission characteristics of glass. The implants were done using the vacuum-arc-based high current metal ion implantation facility developed at Berkeley. The implanted doses were from 3 × 10 16 to 1 × 10 17 cm -2 and the energy was mostly 60 keV. A range of different metal ion species was used, including C, Al, Si, Ti, Fe, Ni, Cu, Y, Ag, Pt and Au. We used soda lime-silica glass (window glass), boron-silica glass (microscope slides), and tin oxide coated glass. The transmission of the glass samples to optical radiation in the wavelength range 300 to 2400 nm was measured. Here we outline the procedure and describe the results of the optical transmission measurements.

  6. Application of a pulsed, RF-driven, multicusp source for low energy plasma immersion ion implantation

    SciTech Connect

    Wengrow, A.B.; Leung, K.N.; Perkins, L.T.; Pickard, D.S.; Rickard, M.; Williams, M.D.; Tucker, M.

    1996-06-01

    The multicusp ion source can produce large volumes of uniform, quiescent, high density plasmas. A plasma chamber suited for plasma immersion ion implantation (PIII) was readily made. Conventional PIII pulses the bias voltage applied to the substrate which is immersed in a CW mode plasma. Here, a method by which the plasma itself is pulsed was developed. Typically pulse lengths of 500 {mu}s are used and are much shorter than that of the substrate voltage pulse (5-15 ms). This approach, together with low gas pressures and low bias voltages, permits the constant energy implantation of an entire wafer simultaneously without glow discharge. Results show that this process can yield implant currents of up to 2.5 mA/cm{sup 2}; thus very short implant times can be achieved. Uniformity of the ion flux is also discussed. As this method can be scaled to any dimension, it can be made to handle any size wafer.

  7. Depth concentrations of deuterium ions implanted into some pure metals and alloys

    NASA Astrophysics Data System (ADS)

    Didyk, A. Yu.; Wiśniewski, R.; Kitowski, K.; Kulikauskas, V.; Wilczynska, T.; Hofman, A.; Shiryaev, A. A.; Zubavichus, Ya. V.

    2012-01-01

    Pure metals (Cu, Ti, Zr, V, Pd) and diluted Pd alloys (Pd-Ag, Pd-Pt, Pd-Ru, Pd-Rh) were implanted by 25-keV deuterium ions at fluences in the range (1.2-2.3) × 1022 m-2. The post-treatment depth distributions of deuterium ions were measured 10 days and three months after the implantation by using Elastic Recoil Detection Analysis (ERDA) and Rutherford Backscattering (RBS). Comparison of the obtained results allowed us to make conclusions about relative stability of deuterium and hydrogen gases in pure metals and diluted Pd alloys. Very high diffusion rates of implanted deuterium ions in V and Pd pure metals and Pd alloys were observed. Small-angle X-ray scattering revealed formation of nanosized defects in implanted corundum and titanium.

  8. Fabrication of highly homogeneous surface-enhanced Raman scattering substrates using Ag ion implantation.

    PubMed

    Li, Wenqing; Xiao, Xiangheng; Dai, Zhigao; Wu, Wei; Cheng, Li; Mei, Fei; Zhang, Xingang; Jiang, Changzhong

    2016-06-29

    In recent times, surface-enhanced Raman scattering (SERS) has attracted attention for its excellent potential application in chemical and biological detection. In this work, we demonstrate that a highly homogeneous SERS substrate can be realized by Ag ion implantation and the subsequent annealing process. Both the implantation and annealing parameters have been optimized for a high sensitivity SERS substrate. The SERS measurement indicates that a sample implanted by 20 kV Ag ions with a dosage of 3  ×  10(16) ions cm(-2) exhibits the highest SERS activity. In addition, the SERS activity of the Ag-implanted substrates depends highly on the annealing temperature and time. Since none of the fabrication processes contain chemical reactions, our substrate is a clean system without any chemical residues. PMID:27167880

  9. Synthesis of (SiC){sub 3}N{sub 4} thin films by ion implantation

    SciTech Connect

    Uslu, C.; Lee, D.H.; Berta, Y.; Park, B.; Thadhani, N.N.; Poker, D.B.

    1993-12-31

    We have investigated the synthesis of carbon-silicon-nitride compounds by ion implantation. In these experiments, 100 keV nitrogen ions were implanted into polycrystalline {beta}-SiC (cubic phase) at various substrate temperatures and ion doses. These thin films were characterized by x-ray diffraction with a position-sensitive detector, transmission electron microscopy with chemical analysis, and Rutherford backscattering spectroscopy. The as-implanted samples show a buried amorphous layer at a depth of 170 nm. Peak concentration of nitrogen saturates at approximately 45 at. % with doses above {approximately} 9.0 {times} 10{sup 17} N/cm{sup 2} at 860{degree}C. These results suggest formation of a new phase by nitrogen implantation into {beta}-SiC.

  10. Effect of 200 keV argon ion implantation on refractive index of polyethylene terepthlate (PET)

    NASA Astrophysics Data System (ADS)

    Kumar, Rajiv; Chawla, Mahak; Rubi, Sharma, Annu; Aggarwal, Sanjeev; Kumar, Praveen; Kanjilal, D.

    2012-06-01

    In the present work, the effect of argon ion implantation has been studied on the refractive index of PET. The specimens were implanted at 200 keV with argon ions in the fluence range of 1×1015 to 1×1017 ions cm-2. The refractive indices have been found to increase with implantation dose and wavelength (in visible region) obtained by using UV-visible spectroscopy. Also a drastic decrease in optical band gap (from 3.63 eV to 1.48eV) and increase in Urbach energy (from 0.29 eV to 3.70 eV) with increase in implantation dose has been observed. The possible correlation between the changes observed in the refractive indices and the Urbachenergyhave been discussed.

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

    NASA Astrophysics Data System (ADS)

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

    2009-03-01

    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.

  12. Fabrication and Characterization of Thin Film Ion Implanted Composite Materials for Integrated Nonlinear Optical Devices

    NASA Technical Reports Server (NTRS)

    Sarkisov, S.; Curley, M.; Williams, E. K.; Wilkosz, A.; Ila, D.; Poker, D. B.; Hensley, D. K.; Smith, C.; Banks, C.; Penn, B.; Clark, R.

    1998-01-01

    Ion implantation has been shown to produce a high density of metal colloids within the layer regions of glasses and crystalline materials. The high-precipitate volume fraction and small size of metal nanoclusters formed leads to values for the third-order susceptibility much greater than those for metal doped solids. This has stimulated interest in use of ion implantation to make nonlinear optical materials. On the other side, LiNbO3 has proved to be a good material for optical waveguides produced by MeV ion implantation. Light confinement in these waveguides is produced by refractive index step difference between the implanted region and the bulk material. Implantation of LiNbO3 with MeV metal ions can therefore result into nonlinear optical waveguide structures with great potential in a variety of device applications. We describe linear and nonlinear optical properties of a waveguide structure in LiNbO3-based composite material produced by silver ion implantation in connection with mechanisms of its formation.

  13. 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.

  14. Neuron attachment properties of carbon negative-ion implanted bioabsorbable polymer of poly-lactic acid

    NASA Astrophysics Data System (ADS)

    Tsuji, Hiroshi; Sasaki, Hitoshi; Sato, Hiroko; Gotoh, Yasuhito; Ishikawa, Junzo

    2002-05-01

    Modification of a bioabsorbable polymer of poly-lactic acid (PLA) by negative carbon ion implantation was investigated with resect to radiation effects on surface physical properties and nerve-cell attachment properties. Carbon negative ions were implanted to PLA at energy of 5-30 keV with a dose of 10 14-10 16 ions/cm 2. Most C-implanted PLA samples showed contact angles near 80° and almost same as that of unimplanted PLA, although a few samples at 5 keV and less 3×10 14 ions/cm 2 had contact angles larger than 90°. The attachment properties of nerve cells of PC-12h (rat adrenal phechromocytoma) in vitro were studied. PC-12h cells attached on the unimplanted region in C-implanted PLA samples at 5 and 10 keV. On the contrary, the nerve cells attached on only implanted region for the C-implanted PLA sample at 30 keV and 1×10 15 ions/cm 2.

  15. 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.

  16. The Development and Evolution of Ion Implanters in the Semiconductor Industry

    NASA Astrophysics Data System (ADS)

    Armour, Dave G.

    2008-11-01

    By the end of the 1960's, the development of ion beam systems for isotope separation and materials research had reached the stage at which knowledge bases in the areas of ion beam formation and transport and the physics of atomic collisions in solids made it practical to consider the use of ion implantation as a means of modifying the near surface properties of solid materials. The beam currents and energies available made the technique particularly compatible with the doping requirements of the silicon devices being produced at that time. However, incorporation of the technique into a high volume manufacturing environment required the immediate development of new target handling facilities and improvements in machine reliability. While the manner in which ion implanters have evolved over the past forty years has continued to be dictated by the changing demands of the silicon processing industry, the dramatic reduction in transistor size and the increase in integrated circuit complexity have had significant implications for the qualities of the ion beams themselves, particularly in high current, ultra-low energy applications. Since the first commercial implanters were introduced, highly developed medium current, high current and high energy machines have evolved. In the medium current and high energy sectors, well understood ion optical principles have enabled ingenious and highly effective beam formation and transport systems to be designed. As these machines evolved, extensive studies of the implanted material using ion beam based techniques such as Rutherford backscattering and channelling provided a growing understanding of the fundamental radiation damage and annealing processes that are inevitably associated with the implantation process. For high current machines, particularly those operating in the so-called eV implantation range, beam formation and transport processes become considerably more complex and established ion optical design principles must be

  17. 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

  18. 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. PMID:22755619

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

    NASA Astrophysics Data System (ADS)

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

    2006-01-01

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

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

    SciTech Connect

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

    2012-06-15

    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 {alpha}-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{sub 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.

  1. Selective electroless copper plating on silicon seeded by copper ion implantation

    NASA Astrophysics Data System (ADS)

    Bhansali, S.; Sood, D. K.; Zmood, R. B.

    1994-12-01

    We report on the successful use of copper (self) ion implantation into silicon to seed the electroless plating of copper on silicon (100) surfaces. Copper ions were implanted into silicon to doses of 5 times 10(exp 14)-6.4 times 10(exp 16) ions\\sq cm using a metal vapour vacuum arc ion implanter at extraction voltages of 10 kV and 20 kV. A copper film was then deposited onto implanted silicon using a commercial electroless plating solution. The ion energy was kept low enough to facilitate a low critical 'seed' threshold dose which was measured to be 2 times 10(exp 15) Cu ions/sq cm. Test patterns were made using polyimide to study the adaptability of this technique to forming thick structures. Plated films were studied with Rutherford backscattering spectrometry, scanning electron microscopy (SEM), profilometry, energy-dispersive X-rays and Auger electron spectroscopy. The adhesion of films was estimated by a 'Scotch tape test'. The adhesion was found to improve with increasing dose. However, thicker films exhibited rather poor adhesion and high internal stress. Detailed examinations of the top and bottom of the film establish that delamination takes place at the amorphous-crystalline interface of the implanted silicon. SEM results show that the films grow first as isolated islands which become larger and eventually coalesce into a continuous film as the plating time is increased.

  2. 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.

  3. Fe-ions implantation to modify TiO2 trilayer films for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Luo, Jun; Pang, Pan; Liao, Bin; Xianying, Wu; Zhang, Xu

    2016-06-01

    A series of Fe-doped TiO2 trilayer films were prepared successfully by using the ion-implantation technique. The aim of the ion implantation was to enhance charge transfer and to reduce charge recombination. A maximum conversion efficiency of 4.86% was achieved in cells using Fe-ion-implanted electrodes with the illumination of 6×1015 atom/cm2. It is 14.1% higher than that of the cells without ion implantations. The significant improvement in conversion efficiency by Fe-ion implantation could be contributed to the enhancement of dye uptake and charge transfer, as indicated from the incident photon-to-collected electron conversion efficiency and ultraviolet-visible measurements. Furthermore, the implanted Fe-ions introduce impurity levels in the bandgap of TiO2, and this improves the electron injection efficiency from lowest unoccupied molecular orbital of excited N719 into the conduction band of TiO2.

  4. THz wave emission of GaAs induced by He+ ion implantation

    NASA Astrophysics Data System (ADS)

    Yang, Kang; Cao, Jianqing; Huang, Can; Ji, Te; Zhang, Zengyan; Liu, Qi; Wu, Shengwei; Lin, Jun; Zhao, Hongwei; Zhu, Zhiyong

    2013-07-01

    Semi-Insulating Gallium Arsenide (SI-GaAs) was implanted with 1.5 MeV He+ ions and THz photoconductive antenna (PCA) was prepared on the implanted SI-GaAs surface. The antenna was applied as the THz wave emission source of a terahertz time domain spectroscopy (THz-TDS) and the THz wave emission ability was studied as a function of the implantation dose. It is found that the THz signal intensity increases with increase of implantation dose, and after reaching to a peak value the THz signal intensity decreases with further implantation. The best THz emission ability was achieved at a dose value between 1 × 1015 and 1 × 1016 ions/cm2. It is believed that the implantation induced defects in the 1 μm-thick surface area are responsible for the enhanced THz emission ability. The work proved that better THz photoconductive antenna than that made by low-temperature-grown GaAs (LT-GaAs) can be produced through He-ion implantation at proper dose.

  5. A study of the structural and magnetic properties of ZnO implanted by Gd ions

    NASA Astrophysics Data System (ADS)

    Macková, A.; Malinský, P.; Sofer, Z.; Šimek, P.; Sedmidubský, D.; Mikulics, M.; Wilhelm, R. A.

    2014-08-01

    The structural and magnetic properties of ZnO (0 0 0 1) single crystals implanted with 200 keV Gd ions up to a fluence of 5 × 1015 cm-2 and subsequently annealed at 800 °C in various atmospheres were studied. The chemical composition and concentration depth profiles of ion-implanted layers were characterised by Rutherford Back-Scattering spectrometry (RBS) and compared to SRIM simulations. The as-implanted Gd depth profiles were found to be broader than those simulated by SRIM, but the projected range coincided well with that simulated. After annealing at 800 °C, the depth profiles became narrower. The structural changes in the layers modified by ion implantation and subsequent annealing were characterised by RBS channelling. The annealing led to partial recrystallisation and a decrease in the number of Gd atoms situated in substitutional positions. Raman spectroscopy showed that the point defects in Zn and O vacancies had been created by implantation and that these defects are most effectively cured after annealing in oxygen atmosphere. AFM analysis was used to determine the surface-morphology changes after the implantation and annealing procedures. The as-implanted samples exhibited ferromagnetism persisting up to room temperature. The annealing procedure led to paramagnetic behaviour, probably caused by the formation of gadolinium clusters.

  6. Lateral displacement induced disorder in L10-FePt nanostructures by ion-implantation

    PubMed Central

    Gaur, N.; Kundu, S.; Piramanayagam, S. N.; Maurer, S. L.; Tan, H. K.; Wong, S. K.; Steen, S. E.; Yang, H.; Bhatia, C. S.

    2013-01-01

    Ion implantation is a promising technique for fabricating high density bit patterned media (BPM) as it may eliminate the requirement of disk planarization. However, there has not been any notable study on the impact of implantation on BPM fabrication of FePt, particularly at nano-scale, where the lateral straggle of implanted ions may become comparable to the feature size. In this work, implantation of antimony ions in patterned and unpatterned L10-FePt thin films has been investigated. Unpatterned films implanted with high fluence of antimony exhibited reduced out-of-plane coercivity and change of magnetic anisotropy from perpendicular direction to film-plane. Interestingly, for samples implanted through patterned masks, the perpendicular anisotropy in the unimplanted region was also lost. This noteworthy observation can be attributed to the displacement of Fe and Pt atoms from the implantation sites to the unimplanted areas, thereby causing a phase disorder transformation from L10 to A1 FePt. PMID:23712784

  7. Characterization of Surface Composition and Microstructure of H13 Steel Implanted by ti Ions Using Masking Implantation Procedure

    NASA Astrophysics Data System (ADS)

    Yang, J. H.; Li, S.; Cheng, M. F.; Luo, X. D.

    Ti and C ions extracted from a metal vapor vacuum arc ion source (MEVVA) were implanted into H13 steel using a masking procedure to ensure reproducible conditions for testing and subsequent analysis. An optical interference microscope and pin-on-disc apparatus investigated the wear and friction characteristics of the steel. The Ti concentration depth profile from Rutherford backscattering spectroscopy was compared with that calculated by a TRIDYN code. It was observed by grazing-angle X-ray diffraction and transmission electron microscopy that carbide of Ti appeared in the doped region. The concentration depth profile and microstructure analysis can serve to illuminate the wear resistance improvement mechanisms of the Ti-implanted steel.

  8. Investigation into Methods to Improve Ion Source Life for Germanium Implantation

    NASA Astrophysics Data System (ADS)

    Sweeney, Joseph; Sergi, Steven; Tang, Ying; Byl, Oleg; Yedave, Sharad; Kaim, Robert; Bishop, Steve

    2011-01-01

    Germanium tetrafluoride has long been the standard dopant gas of choice for germanium implantation processes. While this material maintains several positive attributes (e.g., it is a nonflammable gas that is easily delivered to an ion source), its use can result in extremely short ion source lifetimes. This is especially the case for the situation when an ion implanter runs solely or predominantly GeF4. Presented here is an examination of various potential solutions to the short source life problem, some of which enable significant improvement.

  9. Boron doping to diamond and DLC using plasma immersion ion implantation

    SciTech Connect

    Ikegami, T.; Grotjohn; Reinhard, D.; Asmussen, J.

    1997-12-31

    Controlling carriers in diamond by doping is important to realize diamond electronic devices with advanced electrical characteristics. As a doping method the Plasma Immersion Ion Implantation (PIII) has been gathering attention due to its excellence in making shallow, highly doped regions over large areas, and its high dose rate, good dose controllability and isotropic doping properties. The authors have begun to investigate boron doping of diamond, silicon and diamond-like carbon films using PIII. As a doping source they use the plasma sputtering of a solid boron carbide (B{sub 4}C) target instead of toxic gas source like diborane (B{sub 2}H{sub 6}). The B{sub 4}C target of 1-in. diameter and a substrate (Si, diamond or diamond-like carbon film) are located in the downtown region of an ECR plasma produced by the microwave plasma disc reactor (MPDR) filled with 1--5 mTorr Ar gas. In order to sputter the target a negative self bias from {minus}400V to {minus}700V is induced by applying RF (13.56 MHz) power of 50--200W to the target holder. For boron ion implantation, negative pulses of {minus}1kV to {minus}8kV, 1--5{micro}s pulse duration, 1--200Hz repetition rate are applied to the substrate holder using a voltage pulser which consists of high voltage capacitors and MOSFETs. After thermal treatment of the doped materials their electrical resistivity are measured using the four-probe method. Details of both the PIII source and substrate doping experimental results are shown at the meeting.

  10. Nanostructure and Properties of Corrosion Resistance in C+Ti Multi-Ion-Implanted Steel

    NASA Astrophysics Data System (ADS)

    Zhang, Tong-He; Wu, Yu-Guang; Liu, An-Dong; Zhang, Xu; Wang, Xiao-Yan

    2003-09-01

    The corrosion and pitting corrosion resistance of C+Ti dual and C+Ti+C ternary implanted H13 steel were studied by using a multi-sweep cyclic voltammetry and a scanning electron microscope. The effects of phase formation on corrosion and pitting corrosion resistance were explored. The x-ray diffraction analysis shows that the nanometer-sized precipitate phases consist of compounds of Fe2Ti, TiC, Fe2C and Fe3C in dual implanted layer and even in ternary implanted layer. The passivation layer consists of these nanometer phases. It has been found that the corrosion and pitting corrosion resistance of dual and ternary implanted H13 steel are improved extremely. The corrosion resistance of ternary implanted layer is better than that of dual implantations and is enhanced with the increasing ion dose. When the ion dose of Ti is 6×1017/cm2 in the ternary implantation sample, the anodic peak current density is 95 times less than that of the H13 steel. The pitting corrosion potential of dual and ternary implantation samples is in the range from 55 mV to 160 mV which is much higher than that of the H13 steel. The phases against the corrosion and pitting corrosion are nanometer silkiness phases.

  11. 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.

  12. Broadband luminescence of Cu nanoparticles fabricated in SiO2 by ion implantation.

    PubMed

    Nguyen, Truong Khang; Le, Khai Q; Canimoglu, Adil; Can, Nurdogan

    2016-09-01

    In this study, we investigate optical properties of metal nanoparticle crystals fabricated by implanting copper (Cu) ions into single silica (SiO2) crystals with 400keV at various ion doses. The Cu implanted SiO2 (SiO2:Cu) crystal produces a broadband luminescence emission, ranging from blue to yellow, and having a blue luminescence peak at 546nm. Such anomalous luminescence emission bands suggest that the ion implantation may give rise to aggregation of Cu nanoparticles in the host matrix. The boundary element method-based modelling of a given Cu nanoparticle aggregation was employed to justify the broadband luminescence emission. Formation of Cu nanoparticles in SiO2 is predicted through their optical absorption data. The experimental results are compared with results of Mie calculations and we observe that the higher ion dose produces the larger particle size. PMID:27344525

  13. 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.

  14. 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.

  15. Wettability conversion of an aluminum-hydroxide nanostructure by ion implantation

    NASA Astrophysics Data System (ADS)

    Jeon, Jihoon; Choi, Dukhyun; Kim, Hyungdae; Park, Yong Tae; Choi, Min-Jun; Chung, Kwun-Bum

    2016-04-01

    This work presents a method for controlling the wettability of an aluminum-hydroxide (Al(OH)3) nanostructure by using ion implantation. We implant Xe ions into Al(OH)3 nanostructures at dosages between 5 × 1014 to 1 × 1016 ions/cm2. The microscopic surface morphology of the nanostructure after implantation does not change under our dosing conditions. However, a drastic increase in the surface contact angle (CA) from 0° to 100° is observed at a dosage of 5 × 1015 ions/cm2. We attribute this significant change in CA to the composition and chemical bonding states of carbon contained within the Al(OH)3 nanostructure.

  16. 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.

  17. 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.

  18. The formation of silver metal nanoparticles by ion implantation in silicate glasses

    NASA Astrophysics Data System (ADS)

    Vytykacova, S.; Svecova, B.; Nekvindova, P.; Spirkova, J.; Mackova, A.; Miksova, R.; Böttger, R.

    2016-03-01

    It has been shown that glasses containing silver metal nanoparticles are promising photonics materials for the fabrication of all-optical components. The resulting optical properties of the nanocomposite glasses depend on the composition and structure of the glass, as well as on the type of metal ion implanted and the experimental procedures involved. The main aim of this article was to study the influence of the conditions of the ion implantation and the composition of the glass on the formation of metal nanoparticles in such glasses. Four various types of silicate glasses were implanted with Ag+ ions with different energy (330 keV, 1.2 MeV and 1.7 MeV), with the fluence being kept constant (1 × 1016 ions cm-2). The as-implanted samples were annealed at 600 °C for 1 h. The samples were characterised in terms of: the nucleation of metal nanoparticles (linear optical absorption), the migration of silver through the glass matrix during the implantation and post-implantation annealing (Rutherford backscattering spectroscopy), and the oxidation state of silver (photoluminescence in the visible region).

  19. Ion Implantation in ZnO: Defect Interaction and Impurity Diffusion

    NASA Astrophysics Data System (ADS)

    Yaqoob, Faisal

    In the first part of this research we studied the entropy changes in diffusion prefactor and its effects on diffusion mechanisms and activation energies. We demonstrate a method based on ion implantation and Rutherford backscattering spectroscopy combined with ion channeling (RBS/C) to experimentally determine the diffusion properties of substitutional and interstitial diffusing atoms. The activation energies for each diffusing species are found to be in good agreement with those calculated in previous theoretical studies. The exponential prefactors of the measured diffusion coefficients vary by ten orders of magnitude among substitutional and interstitial diffusing species, allowing us to assign a specific diffusion mechanism to each type of diffusant according to both its diffusion energetics and entropic changes. In addition, the diffusion activation energies and the diffusivity prefactor for the four diffusing species studied are found to follow the Meyer--Neldel relationship with a characteristic excitation energy of ~ 92 meV in ZnO. In another important problem related to the p-doping difficulty in ZnO materials, we studied the effects of ion-implanted hydrogen ions on defect formation and impurity redistribution in ZnO crystals implanted with silver ions. Following Ag ion implantation, the damage level in the ZnO lattice was higher in the sample without H ion implantation than the sample with the H. We found that the damage created to oxygen lattice by the Ag atoms during implantation was higher than the damaged caused to the zinc lattice. Moreover, the Zn lattice recovered faster than the O lattice during thermal annealing. The Ag atoms have higher substitutional fraction in samples without H and increases with annealing temperature. In H implanted samples Ag and H is passivated in defect-related cluster, resulting lower activation of Ag. The diffusion process is affected by H implantation, making it difficult to diffuse to substitutional sites. We discuss

  20. Ion implantation of silicon in gallium arsenide: Damage and annealing characterizations

    NASA Astrophysics Data System (ADS)

    Pribat, D.; Dieumegard, D.; Croset, M.; Cohen, C.; Nipoti, R.; Siejka, J.; Bentini, G. G.; Correra, L.; Servidori, M.

    1983-05-01

    The purpose of this work is twofold: (i) to study the damage induced by ion implantation, with special attention to low implanted doses; (ii) to study the efficiency of annealing techniques — particularly incoherent light annealing — in order to relate the electrical activity of implanted atoms to damage annealing. We have used three methods to study the damage induced by ion implantation: (1) RBS (or nuclear reactions) in random or in channeling geometry (2) RX double crystal diffractometry and (3) electrical measurements (free carrier profiling). Damage induced by silicon implantation at doses >10 14at/cm 2 can be monitored by all three techniques. However, the sensitivity of RBS is poor and hence this technique is not useful for low implantation doses. As device technology requires dopant levels in the range of 5 × 10 12 atoms/cm 2, we are particularly interested to the development of analytical techniques able to detect the damage at this implantation level. The sensitivity of such techniques was checked by studying homogeneously doped (5 × 10 16 e -/cm 3) and semi-insulating GaAs samples implanted with 3 × 10 12 silicon atoms/cm 2 at 150 keV. The substrate temperature during implantation was 200°C. The damage produced in these samples and its subsequent annealing are evidenced by strong changes in X-ray double crystal diffraction spectra. This method hence appears as a good monitoring technique. Annealing of the implanted layers has been performed using incoherent light sources (xenon lamps) either in flash or continuous conditions. Reference samples have also been thermally annealed (850°C, 20 min in capless conditions). The results are compared, and the electrical carrier profiles obtained after continuous incoherent light irradiation indicate that the implanted silicon atoms are almost dully activated. The advantages and disadvantages of incoherent light irradiation are discussed (surface oxidation, surface damage) in comparison with standard

  1. Comparative study of metal and non-metal ion implantation in polymers: Optical and electrical properties

    NASA Astrophysics Data System (ADS)

    Resta, V.; Quarta, G.; Farella, I.; Maruccio, L.; Cola, A.; Calcagnile, L.

    2014-07-01

    The implantation of 1 MeV metal (63Cu+, 107Ag+, 197Au+) and non-metal (4He+, 12C+) ions in a polycarbonate (PC) matrix has been studied in order to evaluate the role of ion species in the modification of optical and electrical properties of the polymer. When the ion fluence is above ∼1 × 1013 ions cm-2, the threshold for latent tracks overlapping is overcome and π-bonded carbon clusters grow and aggregate forming a network of conjugated Cdbnd C bonds. For fluences around 1 × 1017 ions cm-2, the aggregation phenomena induce the formation of amorphous carbon and/or graphite like structures. At the same time, nucleation of metal nanoparticles (NPs) from implanted species can take place when the supersaturation threshold is overcome. The optical absorption of the samples increases in the visible range and the optical band gap redshifts from 3.40 eV up to 0.70 eV mostly due to the carbonization process and the formation of C0x clusters and cluster aggregates. Specific structures in the extinction spectra are observed when metal ions are selected in contrast to the non-metal ion implanted PC, thus revealing the possible presence of noble metal based NPs interstitial to the C0x cluster network. The corresponding electrical resistance decreases much more when metal ions are implanted with at least a factor of 2 orders of magnitude difference than the non-metal ions based samples. An absolute value of ∼107 Ω/sq has been measured for implantation with metals at doses higher than 5 × 1016 ions cm-2, being 1017 Ω/sq the corresponding sheet resistance for pristine PC.

  2. AIDA: A 16-channel amplifier ASIC to read out the advanced implantation detector array for experiments in nuclear decay spectroscopy

    SciTech Connect

    Braga, D.; Coleman-Smith, P. J.; Davinson, T.; Lazarus, I. H.; Page, R. D.; Thomas, S.

    2011-07-01

    We have designed a read-out ASIC for nuclear decay spectroscopy as part of the AIDA project - the Advanced Implantation Detector Array. AIDA will be installed in experiments at the Facility for Antiproton and Ion Research in GSI, Darmstadt. The AIDA ASIC will measure the signals when unstable nuclei are implanted into the detector, followed by the much smaller signals when the nuclei subsequently decay. Implant energies can be as high as 20 GeV; decay products need to be measured down to 25 keV within just a few microseconds of the initial implants. The ASIC uses two amplifiers per detector channel, one covering the 20 GeV dynamic range, the other selectable over a 20 MeV or 1 GeV range. The amplifiers are linked together by bypass transistors which are normally switched off. The arrival of a large signal causes saturation of the low-energy amplifier and a fluctuation of the input voltage, which activates the link to the high-energy amplifier. The bypass transistors switch on and the input charge is integrated by the high-energy amplifier. The signal is shaped and stored by a peak-hold, then read out on a multiplexed output. Control logic resets the amplifiers and bypass circuit, allowing the low-energy amplifier to measure the subsequent decay signal. We present simulations and test results, demonstrating the AIDA ASIC operation over a wide range of input signals. (authors)

  3. 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.

  4. H+ ion implantation on L-arginine monohydrobromide monohydrate single crystal for tuning electro-optical properties

    NASA Astrophysics Data System (ADS)

    Sangeetha, K.; Babu, R. Ramesh; Kumar, Praveen; Bhagavannarayana, G.; Ramamurthi, K.

    2011-03-01

    A nonlinear optical single crystal, l-arginine monohydrobromide monohydrate (LAHBr), has been implanted with 100 keV H+ ions at different ion fluences ranging from 1012 to 1015 ions/cm2 to study the property changes after implantation. Crystalline perfection of the pristine and implanted LAHBr crystals was analyzed using high-resolution X-ray diffraction. The refractive index, birefringence, mechanical stability, dielectric constant and optical absorption bands induced by color centers of the implanted crystals were studied at different ion fluences and compared with pristine LAHBr single crystals.

  5. Effect of H + ion implantation on structural, morphological, optical and dielectric properties of L-arginine monohydrochloride monohydrate single crystals

    NASA Astrophysics Data System (ADS)

    Sangeetha, K.; Babu, R. Ramesh; Kumar, P.; Bhagvannarayana, G.; Ramamurthi, K.

    2011-06-01

    L-arginine monohydrochloride monohydrate (LAHCl) single crystals have been implanted with 100 keV H + ions at different ion fluence ranging from 10 12 to 10 15 ions/cm 2. Implanted LAHCl single crystals have been investigated for property changes. Crystal surface and crystalline perfection of the pristine and implanted crystals were analyzed by atomic force microscope and high-resolution X-ray diffraction studies, respectively. Optical absorption bands induced by colour centers, refractive index and birefringence, mechanical stability and dielectric constant of implanted crystals were studied at different ion fluence and compared with that of pristine LAHCl single crystal.

  6. High energy metal ion implantation using `Magis`, a novel, broad-beam, Marx-generator-based ion source

    SciTech Connect

    Anders, A.; Brown, I.G.; Dickinson, M.R.; MacGill, R.A.

    1996-08-01

    Ion energy of the beam formed by an ion source is proportional to extractor voltage and ion charge state. Increasing the voltage is difficult and costly for extraction voltage over 100 kV. Here we explore the possibility of increasing the charge states of metal ions to facilitate high-energy, broad beam ion implantation at a moderate voltage level. Strategies to enhance the ion charge state include operating in the regimes of high-current vacuum sparks and short pulses. Using a time-of-flight technique we have measured charge states as high as 7+ (73 kA vacuum spark discharge) and 4+ (14 kA short pulse arc discharge), both for copper, with the mean ion charge states about 6.0 and 2.5, respectively. Pulsed discharges can conveniently be driven by a modified Marx generator, allowing operation of ``Magis`` with a single power supply (at ground potential) for both plasma production and ion extraction.

  7. Microstructure characterization and optical properties of sapphire after helium ion implantation

    NASA Astrophysics Data System (ADS)

    Zhong, Mian; Yang, Liang; Shen, Huahai; Liu, Wei; Xiang, Xia; Zheng, Wanguo; Guo, Decheng; Huang, Jin; Sun, Kai; Yuan, Xiaodong

    2015-06-01

    The (0 0 0 1) sapphire samples are irradiated with 60 keV helium ions at the fluences of 5 × 1016, 1 × 1017and 5 × 1017 ions/cm2 at room temperature. After implantation, two broad absorption bands at 320-460 and 480-700 nm are observed and their intensities increase with the increasing ion fluence. The grazing incidence X-ray diffraction results indicate that the {0 0 0 1} diffraction peaks of sapphire decrease and broaden due to the disorientation of the generated crystallites after ion irradiation. The microstructure evolution is examined by the scanning and transmission electron microscopes. The surface becomes rough because of the aggregation of helium bubbles and migration towards the surface. There is a lattice expansion up to ∼4.5% in the implanted area and the lattice distortion measured from dispersion of (1 1 0) diffraction is ∼4.6°. Such strain of crystal lattice is rather large and leads to contrast fluctuation at scale of 1-2 nm (the bubble size). The laser induced damage threshold (LIDT) is investigated to understand the effect of helium ion beam irradiation on the laser damage resistance of sapphire components and the results show that the LIDT decreases from 5.4 to 2.5 J/cm2 due to the absorptive color centers, helium bubbles and defects induced by helium ion implantation. The laser damage morphologies of samples before and after ion implantation are also presented.

  8. Two-dimensional profiling of large tilt angle, low energy boron implanted structure using secondary-ion mass spectrometry

    SciTech Connect

    Cooke, G.A.; Pearson, P.; Gibbons, R.; Dowsett, M.G.; Hill, C.

    1996-01-01

    Experimentally determined two-dimensional dopant maps of implants into semiconductors are required for the calibration and verification of process simulation tools used in very large scale integrated (VLSI) circuit design. Direct measurement with currently available techniques is not possible owing to the physical size of the areas in question. Using a specially fabricated structure and a modified secondary-ion mass spectroscopy instrument, it has been possible to measure profiles with high spatial resolution and sensitivity. In this article we present the results of an investigation of a complex boron implant into silicon, as used in advanced VLSI {ital P}-type metal{endash}oxide{endash}semiconductor source{endash}drain regions, and compare it with results from process simulators. {copyright} {ital 1996 American Vacuum Society}

  9. The effects of junction depth and impurity concentration on ion-implanted, junction solar cells

    SciTech Connect

    Neville, R.C.

    1980-12-01

    This paper presents data resulting from tests on the experimental optimization of the ion-implanted region of horizontal junction, silicon, ion-implanted P+N and N+P solar cells. The experimental data are compared to theoretical predictions based on a simple model and to data obtained with diffused junction solar cells (1). Optimum junction depth and average ion-implanted layer concentration for ion-implanted, silicon, PN junction solar cells under non-concentrated sunlight (approximately AMI conditions) appear to be 0.5..mu..m and 5X10/sup 18/ atoms/cm/sup 3/, respectively. Variation in solar cell efficiency with junction depth is rapid between 0.1 and 0.5..mu..m. Variations of efficiency in response to changes in concentration are minimal over the range tested. Experiments under various illumination conditions indicate increasing efficiency as insolation increases from 83mw/cm/sup 2/ to 100 mw/cm/sup 2/. Comparison with diffused junction, silicon solar cells indicates a potentially greater efficiency for ion-implanted solar cells. However, variation in efficiency between individual solar cells is sufficiently great to warrant further experimentation before reaching any final conclusions.

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

    NASA Astrophysics Data System (ADS)

    Wilbur, P. J.

    1993-09-01

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

  11. Morphologies of fibroblast cells cultured on surfaces of PHB films implanted by hydroxyl ions.

    PubMed

    Hou, T; Zhang, J Z; Kong, L J; Zhang, X E; Hu, P; Zhang, D M; Li, N

    2006-01-01

    Polyhydroxybutyrate (PHB) films were implanted with 40 keV hydroxyl ions with fluences ranging from 1 x 10(12) to 1 x 10(15) ions/cm2, respectively. The as-implanted PHB films were characterized by scanning electron microscopy (SEM), electron spectroscopy for chemical analysis (ESCA) and water contact angle measurements. The surface structures and properties of the as-implanted PHB films were closely related with hydroxyl ion fluence. They were further investigated by inoculating 3T6 fibroblasts cells on their surfaces. Morphologies of the 3T6 fibroblast cells cultured on surfaces of the as-implanted PHB films were observed by SEM. Characterization of the cultural 3T6 cells was analyzed qualitatively. The preliminary experimental results reveal that the bioactivity of the PHB films modified by hydroxyl ion implantation was improved at different levels, and the fluence of 1 x 10(13) ions/cm2 is optimal for PHB film. PMID:16909942

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

    SciTech Connect

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

    2015-10-27

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

  13. Monitoring of ion implantation in microelectronics production environment using multi-channel reflectometry

    NASA Astrophysics Data System (ADS)

    Ebersbach, Peter; Urbanowicz, Adam M.; Likhachev, Dmitry; Hartig, Carsten

    2016-03-01

    Optical metrology techniques such as ellipsometry and reflectometry are very powerful for routine process monitoring and control in the modern semiconductor manufacturing industry. However, both methods rely on optical modeling therefore, the optical properties of all materials in the stack need to be characterized a priori or determined during characterization. Some processes such as ion implantation and subsequent annealing produce slight variations in material properties within wafer, wafer-to-wafer, and lot-to-lot; such variation can degrade the dimensional measurement accuracy for both unpatterned optical measurements as well as patterned (2D and 3D) scatterometry measurements. These variations can be accounted for if the optical model of the structure under investigation allows one to extract not just dimensional but also material information already residing within the optical spectra. This paper focuses on modeling of ion implanted and annealed poly Si stacks typically used in high-k technology. Monitoring of ion implantation is often a blind spot in mass production due to capability issues and other limitations of common methods. Typically, the ion implantation dose can be controlled by research-grade ellipsometers with extended infrared range. We demonstrate that multi-channel spectroscopic reflectometry can also be used for ion implant monitoring in the mass-production environment. Our findings are applicable across all technology nodes.

  14. Sputtering induced changes in defect morphology and dopant diffusion for Si implanted GaAs: Influence of ion energy and implant temperature

    SciTech Connect

    Robinson, H.G.; Deal, M.D.; Lee, C.C.; Haynes, T.E.; Allen, E.L.; Jones, K.S.

    1994-12-01

    Experimental observations of dopant diffusion and defect formation are reported vs ion energy and implant temperature in Si-implanted GaAs. In higher energy implants (>100 keV), little or no diffusion occurs, while at energies less than 100 keV, the amount of dopant redistribution is inversely proportional to energy. Extended defect density shows the opposite trend, increasing with ion energy. Similarly, Si diffusion during post implant annealing decreases by a factor of 2.5 as the implant temperature increases from -2 to 40 C. In this same temperature range, maximum depth and density of extrinsic dislocation loops increases by factors of 3 and 4, respectively. Rutherford backscattering channeling indicates that Si- implanted GaAs undergoes an amorphous-to-crystalline transition at Si implant temperatures between -51 and 40 C. A unified explanation of the effects of ion energy and implant temperature on both diffusion and dislocation formation is proposed based on known differences in sputter yields between low and high energy ions and crystalline and amorphous semiconductors. The model assumes that the sputter yield is enhanced at low implant energies and by amorphization, thus increasing the excess vacancy concentration. Estimates of excess vacancy concentration are obtained by simulations of the diffusion profiles and are quantitatively consistent with a realistic sputter yield enhancement. Removal of the vacancy-rich surface by etching prior to annealing completely suppresses the Si diffusion and increases the dislocation density, lending further experimental support to the model.

  15. The fabrication of silicon nanostructures by focused-ion-beam implantation and TMAH wet etching.

    PubMed

    Sievilä, Päivi; Chekurov, Nikolai; Tittonen, Ilkka

    2010-04-01

    Local gallium implantation of silicon by a focused ion beam (FIB) has been used to create a mask for anisotropic tetramethylammonium hydroxide (TMAH) wet etching. The dependence of the etch stop properties of gallium-doped silicon on the implanted dose has been investigated and a dose of 4 x 10(13) ions cm(- 2) has been determined to be the threshold value for achieving observable etching resistance. Only a thin, approx. 50 nm, surface layer is found to be durable enough to serve as a mask with a high selectivity of at least 2000:1 between implanted and non-implanted areas. The combined FIB-TMAH process has been used to generate various types of 3D nanostructures including nanochannels separated by thin vertical sidewalls with aspect ratios up to 1:30, ultra-narrow (approx. 25 nm) freestanding bridges and cantilevers, and gratings with a resolution of 20 lines microm(- 1). PMID:20215652

  16. Selective Growth of Graphene by Pulsed Laser Annealing Ion Implanted SiC

    NASA Astrophysics Data System (ADS)

    Berke, Kara; Wang, Xiaotie; Rudawski, Nick; Venkatachalam, Dinesh; Fridmann, Joel; Gila, Brent; Ren, Fan; Elliman, Rob; Hebard, Arthur; Appleton, Bill

    2014-03-01

    We report a method for site-selective graphene growth on SiC for direct nano-scale patterning of graphene. Crystalline SiC was implanted with Si and C ions to amorphize the sample surface, then subjected to pulsed laser annealing (PLA); graphene growth occurred only where ions were implanted. PLA parameters including the fluence, number of pulses, and annealing environment were investigated to optimize the growth process. Our previous work involving Au, Cu, and Ge implants in SiC suggested that both the implanted species and surface amorphization affect graphene growth. In this work, we show that surface amorphization alone, without the presence of foreign ionic species, can be used with PLA to create site-selective graphene growth on SiC. Samples were characterized using Raman spectroscopy and cross-sectional transmission electron microscopy. also affiliated with Raith USA, Incorporated.

  17. The fabrication of silicon nanostructures by focused-ion-beam implantation and TMAH wet etching

    NASA Astrophysics Data System (ADS)

    Sievilä, Päivi; Chekurov, Nikolai; Tittonen, Ilkka

    2010-04-01

    Local gallium implantation of silicon by a focused ion beam (FIB) has been used to create a mask for anisotropic tetramethylammonium hydroxide (TMAH) wet etching. The dependence of the etch stop properties of gallium-doped silicon on the implanted dose has been investigated and a dose of 4 × 1013 ions cm - 2 has been determined to be the threshold value for achieving observable etching resistance. Only a thin, approx. 50 nm, surface layer is found to be durable enough to serve as a mask with a high selectivity of at least 2000:1 between implanted and non-implanted areas. The combined FIB-TMAH process has been used to generate various types of 3D nanostructures including nanochannels separated by thin vertical sidewalls with aspect ratios up to 1:30, ultra-narrow (approx. 25 nm) freestanding bridges and cantilevers, and gratings with a resolution of 20 lines µm - 1.

  18. Improved hardness and wear properties of B-ion implanted polycarbonate

    SciTech Connect

    Lee, E.H.; Rao, G.R.; Mansur, L.K. )

    1992-07-01

    Polycarbonate (Lexan) was implanted with 100 and 200 keV B{sup +} ions to doses of 0.26, 0.78, and 2.6{times}10{sup 15} ions/cm{sup 2} at room temperature ({lt}100 {degree}C). Mechanical characterization of implanted materials was carried out by nanoindentation and sliding wear tests. The results showed that the hardness of implanted polycarbonate increased with increasing ion energy and dose, attaining hardness up to 3.2 GPa at a dose of 2.6{times}10{sup 15} ions/cm{sup 2} for 200 keV ions, which is more than 10 times that of the unimplanted polymer. Wear properties were characterized using a reciprocating tribometer with nylon, brass, and SAE 52100 Cr-steel balls with 0.5 and 1 N normal forces for 10 000 cycles. The wear mode varied widely as a function of ion energy, dose, wear ball type, and normal load. For given ion energy, load, and ball type conditions, there was an optimum dose that produced the greatest wear resistance and lowest friction coefficient. For polycarbonate implanted with 0.78{times}10{sup 15} ions/cm{sup 2}, the nylon ball produced no wear after 10 000 cycles. Moreover, the overall friction coefficient was reduced by over 40% by implantation. The results suggest that the potential of ion-beam technology for improving polycarbonate is significant, and that surface-sensitive mechanical properties can be tailored to meet the requirements for applications demanding hardness, wear, and abrasion resistance.

  19. Physics and modeling of ion implantation induced transient deactivation and diffusion processes in boron doped silicon

    NASA Astrophysics Data System (ADS)

    Chakravarthi, Srinivasan

    The economics of silicon processing requires predictive modeling capabilities for the continued rapid advancement of semiconductor technology. This is because it has become prohibitively expensive to develop a new process by running a large series of test lots through multi-billion dollar fabrication facilities. Effective process modeling requires an accurate physical understanding of the various interacting processes. The complexity of this problem is compounded by highly non-equilibrium phenomena associated with IC fabrication processes such as implantation annealing. Point defect supersaturations of many orders of magnitude are introduced following ion implantation, which is used to introduce the dopants into silicon. Such supersaturations dramatically alter the diffusion of dopants and reduce the electrical activation during the initial phase of the anneal. Boron is the primary p-type dopant used in silicon and thus understanding and modeling its deactivation/activation and diffusion is critical to predictive process simulation. Since boron is smaller than silicon, boron agglomerates with interstitials becoming electrically inactive. Modeling of boron clusters is complicated, as there is a huge array of potential boron-interstitial cluster compositions. A physical model for boron clustering is derived by identifying dominant clusters and rate limiting steps via atomistic calculations performed at Lawrence Livermore National Labs. The model is then used successfully to match a wide variety of chemical and electrical data. We further apply this model to understand and successfully predict ultra shallow junction formation. We find it is possible to explain some intriguing phenomenon observed during the formation of ultra shallow junctions, like saturation in junction depth despite increasing ramp-up rates. Researchers are exploring novel experimental processing steps like high energy Si pre-implants to produce highly active and shallow B junctions. To understand

  20. Method and means of directing an ion beam onto an insulating surface for ion implantation or sputtering

    DOEpatents

    Gruen, Dieter M.; Krauss, Alan R.; Siskind, Barry

    1981-01-01

    A beam of ions is directed under control onto an insulating surface by supplying simultaneously a stream of electrons directed at the same surface in a quantity sufficient to neutralize the overall electric charge of the ion beam and result in a net zero current flow to the insulating surface. The ion beam is adapted particularly both to the implantation of ions in a uniform areal disposition over the insulating surface and to the sputtering of atoms or molecules of the insulator onto a substrate.

  1. Non-mass-analyzed ion implantation equipment for high volume solar cell production

    NASA Technical Reports Server (NTRS)

    Armini, A. J.; Bunker, S. N.; Spitzer, M. B.

    1982-01-01

    Equipment designed for junction formation in silicon solar cells is described. The equipment, designed for a production level of approximately one megawatt per year, consists of an ion implanter and annealer. Low cost is achieved by foregoing the use of mass analysis during the implantation, and by the use of a belt furnace for annealing. Results of process development, machine design and cost analysis are presented.

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

    SciTech Connect

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

    2004-12-01

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

  3. A Case Study of Ion Implant In-Line Statistical Process Control

    NASA Astrophysics Data System (ADS)

    Zhao, Zhiyong; Ramczyk, Kenneth; Hall, Darcy; Wang, Linda

    2005-09-01

    Ion implantation is one of the most critical processes in the front-end-of-line for ULSI manufacturing. With more complexity in device layout, the fab cycle time can only be expected to be longer. To ensure yield and consistent device performance it is very beneficial to have a Statistical Process Control (SPC) practice that can detect tool issues to prevent excursions. Also, implanters may abort a process due to run-time issues. It requires human intervention to dispose of the lot. Since device wafers have a fixed flow plan and can only do anneal at certain points in the manufacturing process, it is not practical to use four-point probe to check such implants. Pattern recognition option on some of the metrology tools, such as ThermaWave (TWave), allows user to check an open area on device wafers for implant information. The two cited reasons prompted this work to look into the sensitivity of TWave with different implant processes and the possibility of setting up an SPC practice in a high-volume manufacturing fab. In this work, the authors compare the test wafer result with that of device wafers with variations in implant conditions such as dose, implant angle, energy, etc. The intention of this work is to correlate analytical measurement such as sheet resistance (Rs) and Secondary Ion Mass Spectrometry (SIMS) with device data such as electrical testing and sort yield. For a ± 1.5% TWave control limit with the tested implant processes in this work, this translates to about 0.5° in implant angle control or 2% to 8% dose change, respectively. It is understood that the dose sensitivity is not good since the tested processes are deep layer implants. Based on the statistics calculation, we assess the experimental error bar is within 1% of the measured values.

  4. Behavior of ion-implanted junction diodes in 3C SiC

    NASA Technical Reports Server (NTRS)

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

    1987-01-01

    p-n junction diodes have been formed by ion implantation of B or Al in 3C SiC and annealing at 1365 C. The current-voltage characteristics of the Al-implanted structures show little rectification. The B-implanted diodes show rectification, with ideality factors of 2.2 and higher, breakdown voltages between 5 and 10 V, and a series resistance of the order of 20 kohm. The current-voltage characteristics were measured between room temperature and 270 C. The extracted ideality factors increase with temperature.

  5. Formation of YBa2Cu3O7 superconducting films by ion implantation

    NASA Astrophysics Data System (ADS)

    Nastasi, M.; Tesmer, J. R.; Hollander, M. G.; Smith, J. F.; Maggiore, C. J.

    1988-05-01

    Superconducting thin films were fabricated by ion implanting Y into a base material formed by the coevaporation of BaF2 and Cu. The implantations were carried out at 77 K and resulted in the formation of an amorphous Y-Ba-Cu-F surface layer. Oxygen annealing with the addition of water vapor renders the base material insulating with a room-temperature resistance of 100,000 ohm. An identical annealing treatment on the Y-implanted material produces a superconductor with an onset temperature of 85 K.

  6. Optimum flash lamp annealing conditions for fabrication of low dose ion-implanted Si solar cells

    NASA Astrophysics Data System (ADS)

    Usami, A.; Nishioka, H.; Inoue, Y.

    1984-06-01

    A method to fabricate silicon solar cells was developed around low dose (nonamorphized) ion implantation and Xe flash lamp annealing under assist heating (350-550 C). Solar cells fabricated by low dose B-11/+/ (p+/n-type cell) and P-31/+/ (n+/p-type cell) implantation and flash lamp annealing showing a high efficiency of about 10.4 percent (AM2) without AR coating and BSF structures. The results were compared with those of high dose implanted cells reported previously (in this transaction). Effects of assist heating temperature were also examined.

  7. 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.

  8. Intrinsic Point-Defect Balance in Self-Ion-Implanted ZnO

    NASA Astrophysics Data System (ADS)

    Neuvonen, Pekka T.; Vines, Lasse; Svensson, Bengt G.; Kuznetsov, Andrej Yu.

    2013-01-01

    The role of excess intrinsic atoms for residual point defect balance has been discriminated by implanting Zn or O ions into Li-containing ZnO and monitoring Li redistribution and electrical resistivity after postimplant anneals. Strongly Li-depleted regions were detected in the Zn-implanted samples at depths beyond the projected range (Rp) upon annealing ≥600°C, correlating with a resistivity decrease. In contrast, similar anneals of the O-implanted samples resulted in Li accumulation at Rp and an increased resistivity. Control samples implanted with Ar or Ne ions, yielding similar defect production as for the Zn or O implants but with no surplus of intrinsic atoms, revealed no Li depletion. Thus, the depletion of Li shows evidence of excess Zn interstitials (ZnI) being released during annealing of the Zn-implanted samples. These ZnI’s convert substitutional Li atoms (LiZn) into highly mobile interstitial ones leading to the strongly Li-depleted regions. In the O-implanted samples, the high resistivity provides evidence of stable OI-related acceptors.

  9. Optical and electrical studies of ZnO thin films heavily implanted with silver ions

    NASA Astrophysics Data System (ADS)

    Lyadov, N. M.; Gumarov, A. I.; Valeev, V. F.; Nuzhdin, V. I.; Khaibullin, R. I.; Faizrakhmanov, I. A.

    2014-12-01

    Thin films of zinc oxide (ZnO) with the thickness of 200 nm have been deposited on quartz substrates by using ion-beam sputtering technique. Then Ag+ ions with the energy of 30 keV have been implanted into as-deposited ZnO films to the fluences in the range of (0.25-1.00)×1017 ions/cm2 to form ZnO:Ag composite layers with different concentrations of the silver impurity. The analysis of the microstructure has shown that the thickness of the ZnO film decreases, and the Ag dopant concentration tends to the saturation with increasing Ag implantation fluence. The ZnO:Ag composite layers reveal the optical selective absorption at the wavelength of the surface plasmon resonance that is typical for silver nanoparticles dispersed in the ZnO matrix. The red shift of the plasmon resonance peak from 480 to 500 nm is observed with the increase in the implantation fluence to 0.75×1017 Ag ions/cm2. Then the absorption peak position starts the backward motion, and the absorption intensity decreases with the subsequent increase in the implantation fluence. The non-monotonic dependence of the absorption peak position on the implantation fluence has been analyzed within of Maxwell Garnet theory and taking into account the strong sputtering of ZnO films during implantation. The ZnO:Ag composite layers exhibit the p-type conductivity indicating that a part of Ag+ ions is in the form of acceptor impurities implanted into the ZnO lattice.

  10. 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.

  11. Properties of polyimide, polyetheretherketone and polyethyleneterephthalate implanted by Ni ions to high fluences

    NASA Astrophysics Data System (ADS)

    Malinsky, P.; Mackova, A.; Hnatowicz, V.; Khaibullin, R. I.; Valeev, V. F.; Slepicka, P.; Svorcik, V.; Slouf, M.; Perina, V.

    2012-02-01

    Polyimide (PI), polyetheretherketone (PEEK) and polyethyleneterephthalate (PET) were implanted with 40 keV Ni + ions at RT to the fluences (0.25-1.5) × 10 17 cm -2 at ion current density of 4 μA cm -2. Then some of the samples were annealed at the temperatures close to the polymer glassy transition temperature. Depth profiles of the Ni atoms in the as implanted and annealed samples were determined by RBS method. The profiles in the as implanted samples agree reasonably with those simulated using TRYDIN code. The implanted Ni atoms tend to aggregate into nano-particles, the size and distribution of which was determined from TEM images. The nano-particle size increases with increasing ion fluence. Subsequent annealing leads to a reduction in the nanoparticle size. The surface morphology of the implanted and annealed samples was studied using AFM. The changes in the polymer sheet resistance of the implanted and annealed samples were measured by standard two-point technique. The sheet resistance decreases with increasing temperature of annealing.

  12. Relaxation of strain during solid phase epitaxial growth of Ge + ion implanted layers in silicon

    NASA Astrophysics Data System (ADS)

    Holmén, G.; Songsiriritthigul, Prayoon

    1998-09-01

    Formation of Si 1- xGe x-alloy layers by solid phase epitaxial growth (SPEG) of Ge + ion implanted silicon has been studied. The ion implantations were performed with 40, 100, 150, 200 and 300 keV 74Ge + ions and various ion doses. The SPEG of the ion implanted layers was carried out in a conventional furnace at 850°C for 20 min under a flow of nitrogen gas. The Si 1- xGe x-alloy layers were characterised by Rutherford backscattering spectrometry and transmission electron microscopy (TEM). For a given ion energy, a Si 1- xGe x-alloy layer with no observable extended defects can be manufactured if the ion dose is below a critical value and strain-induced defects are formed in the alloy layer when the ion dose is equal to or above this value. The critical Ge + ion dose increases with ion energy, while the critical maximum Ge concentration decreases. For ion energies ⩽150 keV, the defects observed in the alloy layers are mostly stacking faults parallel to the {1 1 1} planes. For higher ion energies, 200 keV and above, the majority of defects in the alloy layer are hairpin dislocations. In the whole ion energy range, the critical ion dose and the depth position of the nucleation site for the stacking faults obtained from the measurements are in good agreement with theoretical predictions. Extended defects are formed in the alloy layer during the SPEG when the regrowth of the crystalline/amorphous interface has reached the depth position in the crystal where the accumulated strain energy density is equal to the critical value of 235 mJ/m 2.

  13. Method for Providing Semiconductors Having Self-Aligned Ion Implant

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G. (Inventor)

    2014-01-01

    A method is disclosed that provides a self-aligned nitrogen-implant particularly suited for a Junction Field Effect Transistor (JFET) semiconductor device preferably comprised of a silicon carbide (SiC). This self-aligned nitrogen-implant allows for the realization of durable and stable electrical functionality of high temperature transistors such as JFETs. The method implements the self-aligned nitrogen-implant having predetermined dimensions, at a particular step in the fabrication process, so that the SiC junction field effect transistors are capable of being electrically operating continuously at 500.degree. C. for over 10,000 hours in an air ambient with less than a 10% change in operational transistor parameters.

  14. Method for Providing Semiconductors Having Self-Aligned Ion Implant

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G. (Inventor)

    2011-01-01

    A method is disclosed that provides a self-aligned nitrogen-implant particularly suited for a Junction Field Effect Transistor (JFET) semiconductor device preferably comprised of a silicon carbide (SiC). This self-aligned nitrogen-implant allows for the realization of durable and stable electrical functionality of high temperature transistors such as JFETs. The method implements the self-aligned nitrogen-implant having predetermined dimensions, at a particular step in the fabrication process, so that the SiC junction field effect transistors are capable of being electrically operating continuously at 500.degree. C. for over 10,000 hours in an air ambient with less than a 10% change in operational transistor parameters.

  15. Application of Coaxial Ion Gun for Film Generation and Ion Implantation

    NASA Astrophysics Data System (ADS)

    Takatsu, Mikio; Asai, Tomohiko; Kurumi, Satoshi; Suzuki, Kaoru; Hirose, Hideharu; Masutani, Shigeyuki

    A magnetized coaxial plasma gun (MCPG) is here utilized for deposition on high-melting-point metals. MCPGs have hitherto been studied mostly in the context of nuclear fusion research, for particle and magnetic helicity injection and spheromak formation. During spheromak formation, the electrode materials are ionized and mixed into the plasmoid. In this study, this ablation process by gun-current sputtering is enhanced for metallic thin-film generation. In the proposed system geometry, only ionized materials are electromagnetically accelerated by the self-Lorentz force, with ionized operating gas as a magnetized thermal plasmoid, contributing to the thin-film deposition. This reduces the impurity and non-uniformity of the deposited thin-film. Furthermore, as the ions are accelerated in a parallel direction to the injection axis, vertical implantation of the ions into the substrate surface is achieved. To test a potential application of the developed system, experiments were conducted involving the formation of a buffer layer on hard ceramics, for use in dental materials.

  16. 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.

  17. Non-Contact Measurement of Thermal Diffusivity in Ion-Implanted Nuclear Materials.

    PubMed

    Hofmann, F; Mason, D R; Eliason, J K; Maznev, A A; Nelson, K A; Dudarev, S L

    2015-01-01

    Knowledge of mechanical and physical property evolution due to irradiation damage is essential for the development of future fission and fusion reactors. Ion-irradiation provides an excellent proxy for studying irradiation damage, allowing high damage doses without sample activation. Limited ion-penetration-depth means that only few-micron-thick damaged layers are produced. Substantial effort has been devoted to probing the mechanical properties of these thin implanted layers. Yet, whilst key to reactor design, their thermal transport properties remain largely unexplored due to a lack of suitable measurement techniques. Here we demonstrate non-contact thermal diffusivity measurements in ion-implanted tungsten for nuclear fusion armour. Alloying with transmutation elements and the interaction of retained gas with implantation-induced defects both lead to dramatic reductions in thermal diffusivity. These changes are well captured by our modelling approaches. Our observations have important implications for the design of future fusion power plants. PMID:26527099

  18. Non-Contact Measurement of Thermal Diffusivity in Ion-Implanted Nuclear Materials

    SciTech Connect

    Hofmann, F.; Mason, D. R.; Eliason, J. K.; Maznev, A. A.; Nelson, K. A.; Dudarev, S. L.

    2015-11-03

    Knowledge of mechanical and physical property evolution due to irradiation damage is essential for the development of future fission and fusion reactors. Ion-irradiation provides an excellent proxy for studying irradiation damage, allowing high damage doses without sample activation. Limited ion-penetration-depth means that only few-micron-thick damaged layers are produced. Substantial effort has been devoted to probing the mechanical properties of these thin implanted layers. Yet, whilst key to reactor design, their thermal transport properties remain largely unexplored due to a lack of suitable measurement techniques. Here we demonstrate non-contact thermal diffusivity measurements in ion-implanted tungsten for nuclear fusion armour. Alloying with transmutation elements and the interaction of retained gas with implantation-induced defects both lead to dramatic reductions in thermal diffusivity. These changes are well captured by our modelling approaches. Our observations have important implications for the design of future fusion power plants.

  19. Non-Contact Measurement of Thermal Diffusivity in Ion-Implanted Nuclear Materials

    DOE PAGESBeta

    Hofmann, F.; Mason, D. R.; Eliason, J. K.; Maznev, A. A.; Nelson, K. A.; Dudarev, S. L.

    2015-11-03

    Knowledge of mechanical and physical property evolution due to irradiation damage is essential for the development of future fission and fusion reactors. Ion-irradiation provides an excellent proxy for studying irradiation damage, allowing high damage doses without sample activation. Limited ion-penetration-depth means that only few-micron-thick damaged layers are produced. Substantial effort has been devoted to probing the mechanical properties of these thin implanted layers. Yet, whilst key to reactor design, their thermal transport properties remain largely unexplored due to a lack of suitable measurement techniques. Here we demonstrate non-contact thermal diffusivity measurements in ion-implanted tungsten for nuclear fusion armour. Alloying withmore » transmutation elements and the interaction of retained gas with implantation-induced defects both lead to dramatic reductions in thermal diffusivity. These changes are well captured by our modelling approaches. Our observations have important implications for the design of future fusion power plants.« less

  20. Inducing the paramagnetic Meissner effect in Nb disks by surface ion implantation

    SciTech Connect

    Thompson, D.J.; Wenger, L.E.; Chen, J.T.

    1996-12-01

    After implanting Kr ions to a depth of 120 nm below both surfaces of disk-shaped Nb samples, the magnetization in a field-cooling measurement becomes positive at temperatures slightly below the superconducting transition temperature {ital T}{sub {ital c}}{approx_equal}9.2 K. In contrast, the field-cooled magnetization on similar disks prior to the ion implanting was diamagnetic. This behavior confirms earlier evidence that the paramagnetic Meissner effect (PME) is extremely sensitive to the surface microstructure. Furthermore the occurrence of the PME in these ion-implanted Nb disks results from the existence of lower {ital T}{sub {ital c}} surface defects having a sufficient depth relative to the disk thickness such that the resulting strong flux pinning from these defects gives rise to an inhomogeneous local field distribution. {copyright} {ital 1996 The American Physical Society.}

  1. Non-Contact Measurement of Thermal Diffusivity in Ion-Implanted Nuclear Materials

    PubMed Central

    Hofmann, F.; Mason, D. R.; Eliason, J. K.; Maznev, A. A.; Nelson, K. A.; Dudarev, S. L.

    2015-01-01

    Knowledge of mechanical and physical property evolution due to irradiation damage is essential for the development of future fission and fusion reactors. Ion-irradiation provides an excellent proxy for studying irradiation damage, allowing high damage doses without sample activation. Limited ion-penetration-depth means that only few-micron-thick damaged layers are produced. Substantial effort has been devoted to probing the mechanical properties of these thin implanted layers. Yet, whilst key to reactor design, their thermal transport properties remain largely unexplored due to a lack of suitable measurement techniques. Here we demonstrate non-contact thermal diffusivity measurements in ion-implanted tungsten for nuclear fusion armour. Alloying with transmutation elements and the interaction of retained gas with implantation-induced defects both lead to dramatic reductions in thermal diffusivity. These changes are well captured by our modelling approaches. Our observations have important implications for the design of future fusion power plants. PMID:26527099

  2. 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. PMID:15585228

  3. First results from the Los Alamos plasma source ion implantation experiment

    SciTech Connect

    Rej, D.J.; Faehl, R.J.; Gribble, R.J.; Henins, I.; Kodali, P.; Nastasi, M.; Reass, W.A.; Tesmer, J.; Walter, K.C.; Wood, B.P.; Conrad, J.R.; Horswill, N.; Shamim, M.; Sridharan, K.

    1993-12-01

    A new facility is operational at Los Alamos to examine plasma source ion implantation on a large scale. Large workpieces can be treated in a 1.5-m-diameter, 4.6-m-long plasma vacuum chamber. Primary emphasis is directed towards improving tribological properties of metal surfaces. First experiments have been performed at 40 kV with nitrogen plasmas. Both coupons and manufactured components, with surface areas up to 4 m{sup 2}, have been processed. Composition and surface hardness of implanted materials are evaluated. Implant conformality and dose uniformity into practical geometries are estimated with multidimensional particle-in-cell computations of plasma electron and ion dynamics, and Monte Carlo simulations of ion transport in solids.

  4. Non-Contact Measurement of Thermal Diffusivity in Ion-Implanted Nuclear Materials

    NASA Astrophysics Data System (ADS)

    Hofmann, F.; Mason, D. R.; Eliason, J. K.; Maznev, A. A.; Nelson, K. A.; Dudarev, S. L.

    2015-11-01

    Knowledge of mechanical and physical property evolution due to irradiation damage is essential for the development of future fission and fusion reactors. Ion-irradiation provides an excellent proxy for studying irradiation damage, allowing high damage doses without sample activation. Limited ion-penetration-depth means that only few-micron-thick damaged layers are produced. Substantial effort has been devoted to probing the mechanical properties of these thin implanted layers. Yet, whilst key to reactor design, their thermal transport properties remain largely unexplored due to a lack of suitable measurement techniques. Here we demonstrate non-contact thermal diffusivity measurements in ion-implanted tungsten for nuclear fusion armour. Alloying with transmutation elements and the interaction of retained gas with implantation-induced defects both lead to dramatic reductions in thermal diffusivity. These changes are well captured by our modelling approaches. Our observations have important implications for the design of future fusion power plants.

  5. Microstructural investigation of alumina implanted with 30 keV nitrogen ions

    NASA Astrophysics Data System (ADS)

    Shikha, Deep; Jha, Usha; Sinha, S. K.; Barhai, P. K.; Sarkhel, G.; Nair, K. G. M.; Dash, S.; Tyagi, A. K.; Kothari, D. C.

    2007-11-01

    Among ceramics, alumina is being widely used as biomaterials now these days. It is being used as hip joints, tooth roots etc. Ion implantation has been employed to modify its surface without changing it bulk properties. 30 keV nitrogen with varying ion dose ranging from 5 × 10 15 ions/cm 2 to 5 × 10 17 ions/cm 2 is implanted in alumina. Surface morphology has been studied with optical microscope and atomic force microscope (AFM). Improvement in brittleness has been observed with the increase in ion dose. Compound formation and changes in grain size have been studied using X-Ray diffraction (XRD). AlN compound formation is also observed by Fourier transform infrared spectroscopy (FTIR). The change in the grain size is related with the nanohardness and Hall-Petch relationship is verified.

  6. Deuterium-incorporated gate oxide of MOS devices fabricated by using deuterium ion implantation

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Sung; Lear, Kevin L.

    2012-04-01

    In the aspect of metal-oxide-semiconductor (MOS) device reliability, deuterium-incorporated gate oxide could be utilized to suppress the wear-out that is combined with oxide trap generation. An alternative deuterium process for the passivation of oxide traps or defects in the gate oxide of MOS devices has been suggested in this study. The deuterium ion is delivered to the location where the gate oxide resides by using an implantation process and subsequent N2 annealing process at the back-end of metallization process. A conventional MOS field-effect transistor (MOSFET) with a 3-nm-thick gate oxide and poly-to-ploy capacitor sandwiched with 20-nm-thick SiO2 were fabricated in order to demonstrate the deuterium effect in our process. An optimum condition of ion implantation was necessary to account for the topography of the overlaying layers in the device structure and to minimize the physical damage due to the energy of the implanted ion. Device parameter variations, the gate leakage current, and the dielectric breakdown phenomenon were investigated in the deuterium-ion-implanted devices. We found the isotope effect between hydrogen- and deuterium-implanted devices and an improved electrical reliability in the deuterated gate oxide. This implies that deuterium bonds are generated effectively at the Si/SiO2 interface and in the SiO2 bulk.

  7. High-precision figure correction of x-ray telescope optics using ion implantation

    NASA Astrophysics Data System (ADS)

    Chalifoux, Brandon; Sung, Edward; Heilmann, Ralf K.; Schattenburg, Mark L.

    2013-09-01

    Achieving both high resolution and large collection area in the next generation of x-ray telescopes requires highly accurate shaping of thin mirrors, which is not achievable with current technology. Ion implantation offers a promising method of modifying the shape of mirrors by imparting internal stresses in a substrate, which are a function of the ion species and dose. This technique has the potential for highly deterministic substrate shape correction using a rapid, low cost process. Wafers of silicon and glass (D-263 and BK-7) have been implanted with Si+ ions at 150 keV, and the changes in shape have been measured using a Shack-Hartmann metrology system. We show that a uniform dose over the surface repeatably changes the spherical curvature of the substrates, and we show correction of spherical curvature in wafers. Modeling based on experiments with spherical curvature correction shows that ion implantation could be used to eliminate higher-order shape errors, such as astigmatism and coma, by using a spatially-varying implant dose. We will report on progress in modelling and experimental tests to eliminate higher-order shape errors. In addition, the results of experiments to determine the thermal and temporal stability of implanted substrates will be reported.

  8. Peculiarities and application perspectives of metal-ion implants in glasses

    SciTech Connect

    Mazzoldi, P.; Gonella, F.; Arnold, G.W.; Battaglin, G.; Bertoncello, R.

    1993-12-31

    Ion implantation in insulators causes modifications in the refractive-index as a result of radiation damage, phase separation, or compound formation. As a consequence, light waveguides may be formed with interesting applications in the field of optoelectronics. Recently implantation of metals ions (e.g. silver, copper, gold, lead,...) showed the possibility of small radii colloidal particles formation, in a thin surface layer of the glass substrate. These particles exhibit an electron plasmon resonance which depends on the optical constants of the implanted metal and on the refractive-index of the glass host. The non-linear optical properties of such colloids, in particular the enhancement of optical Kerr susceptibility, suggest that the, ion implantation technique may play an important role for the production of all-optical switching devices. In this paper an analysis of the state-of-the-art of the research in this field will be presented in the framework of ion implantation in glass physics and chemistry.

  9. 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.

  10. 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.

  11. 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

    The objective of this program is the investigation and evaluation of the capabilities of the ion implantation process for the production of photovoltaic cells from a variety of present-day, state-of-the-art, low-cost silicon sheet materials. Task 1 of the program concerns application of ion implantation and furnace annealing to fabrication of cells made from dendritic web silicon. Task 2 comprises the application of ion implantation and pulsed electron beam annealing (PEBA) to cells made from SEMIX, SILSO, heat-exchanger-method (HEM), edge-defined film-fed growth (EFG) and Czochralski (CZ) silicon. The goals of Task 1 comprise an investigation of implantation and anneal processes applied to dendritic web. A further goal is the evaluation of surface passivation and back surface reflector formation. In this way, processes yielding the very highest efficiency can be evaluated. Task 2 seeks to evaluate the use of PEBA for various sheet materials. A comparison of PEBA to thermal annealing will be made for a variety of ion implantation processes.

  12. 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.

  13. 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.

  14. Oxygen ion implantation induced microstructural changes and electrical conductivity in Bakelite RPC detector material

    NASA Astrophysics Data System (ADS)

    Kumar, K. V. Aneesh; Ranganathaiah, C.; Kumarswamy, G. N.; Ravikumar, H. B.

    2016-05-01

    In order to explore the structural modification induced electrical conductivity, samples of Bakelite Resistive Plate Chamber (RPC) detector materials were exposed to 100 keV Oxygen ion in the fluences of 1012, 1013, 1014 and 1015 ions/cm2. Ion implantation induced microstructural changes have been studied using Positron Annihilation Lifetime Spectroscopy (PALS) and X-Ray Diffraction (XRD) techniques. Positron lifetime parameters viz., o-Ps lifetime and its intensity shows the deposition of high energy interior track and chain scission leads to the formation of radicals, secondary ions and electrons at lower ion implantation fluences (1012 to1014 ions/cm2) followed by cross-linking at 1015 ions/cm2 fluence due to the radical reactions. The reduction in electrical conductivity of Bakelite detector material is correlated to the conducting pathways and cross-links in the polymer matrix. The appropriate implantation energy and fluence of Oxygen ion on polymer based Bakelite RPC detector material may reduce the leakage current, improves the efficiency, time resolution and thereby rectify the aging crisis of the RPC detectors.

  15. 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.

  16. 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.

  17. N-Ion-implanted TiO2 photoanodes in quantum dot-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Sudhagar, P.; Asokan, K.; Ito, E.; Kang, Yong Soo

    2012-03-01

    Hierarchical nanostructured titanium dioxide (TiO2) clumps were fabricated using electrostatic spray with subsequent nitrogen-ion doping by an ion-implantation technique for improvement of energy conversion efficiency for quantum dot-sensitized solar cells (QDSCs). CdSe quantum dots were directly assembled on the produced N-ion-implanted TiO2 photoanodes by chemical bath deposition, and their photovoltaic performance was evaluated in a polysulfide electrolyte with a Pt counter electrode. We found that the photovoltaic performance of TiO2 electrodes was improved by nearly 145% upon N-ion implantation. The efficiency improvement seems to be due to (1) the enhancement of electron transport through the TiO2 layer by inter-particle necking of primary TiO2 particles and (2) an increase in the recombination resistance at TiO2/QD/electrolyte interfaces by healing the surface states or managing the oxygen vacancies upon N-ion doping. Therefore, N-ion-doped photoanodes offer a viable pathway to develop more efficient QD or dye-sensitized solar cells.Hierarchical nanostructured titanium dioxide (TiO2) clumps were fabricated using electrostatic spray with subsequent nitrogen-ion doping by an ion-implantation technique for improvement of energy conversion efficiency for quantum dot-sensitized solar cells (QDSCs). CdSe quantum dots were directly assembled on the produced N-ion-implanted TiO2 photoanodes by chemical bath deposition, and their photovoltaic performance was evaluated in a polysulfide electrolyte with a Pt counter electrode. We found that the photovoltaic performance of TiO2 electrodes was improved by nearly 145% upon N-ion implantation. The efficiency improvement seems to be due to (1) the enhancement of electron transport through the TiO2 layer by inter-particle necking of primary TiO2 particles and (2) an increase in the recombination resistance at TiO2/QD/electrolyte interfaces by healing the surface states or managing the oxygen vacancies upon N-ion doping

  18. 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.

  19. 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.

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

    SciTech Connect

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

    2008-11-03

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

  1. Single-walled carbon nanotube growth from ion implanted Fe catalyst

    SciTech Connect

    Choi, Yongho; Sippel-Oakley, Jennifer; Ural, Ant

    2006-10-09

    The authors present experimental evidence that single-walled carbon nanotubes can be grown by chemical vapor deposition from ion implanted iron catalyst. They systematically characterize the effect of ion implantation dose and energy on the catalyst nanoparticles and nanotubes formed at 900 deg. C. They also fabricate a micromachined silicon grid for direct transmission electron microscopy characterization of the as-grown nanotubes. This work opens up the possibility of controlling the origin of single-walled nanotubes at the nanometer scale and of integrating them into nonplanar three-dimensional device structures with precise dose control.

  2. Influence of annular magnet on discharge characteristics in enhanced glow discharge plasma immersion ion implantation

    SciTech Connect

    Li Liuhe; Wang Zhuo; Lu Qiuyuan; Fu, Ricky K. Y.; Chu, Paul K.; Pang Enjing; Dun Dandan; He Fushun; Li Fen

    2011-01-10

    A permanent annular magnet positioned at the grounded anode alters the discharge characteristics in enhanced glow discharge plasma immersion ion implantation (EGD-PIII). The nonuniform magnetic field increases the electron path length and confines electron motion due to the magnetic mirror effect and electron-neutral collisions thus occur more frequently. The plasma potential and ion density measured by a Langmuir probe corroborate that ionization is improved near the grounded anode. This hybrid magnetic field EGD-PIII method is suitable for implantation of gases with low ionization rates.

  3. Ion implantation doping and isolation of GaN

    SciTech Connect

    Pearton, S.J.; Vartuli, C.B.; Zolper, J.C.; Yuan, C.; Stall, R.A.

    1995-09-04

    {ital N}- and {ital p}-type regions have been produced in GaN using Si{sup +} and Mg{sup +}/P{sup +} implantation, respectively, and subsequent annealing at {similar_to}1100 {degree}C. Carrier activation percentages of 93% for Si and 62% for Mg were obtained for implant doses of 5{times}10{sup 14} cm{sup {minus}2} of each element. Conversely, highly resistive regions ({gt}5{times}10{sup 9} {Omega}/{D`Alembertian}) can be produced in initially {ital n}- or {ital p}- type GaN by N{sup +} implantation and subsequent annealing at {similar_to}750 {degree}C. The activation energy of the deep states controlling the resistivity of these implant-isolated materials is in the range 0.8--0.9 eV. These process modules are applicable to the fabrication of a variety of different GaN-based electronic and photonic devices. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  4. Tunnel oxide passivated contacts formed by ion implantation for applications in silicon solar cells

    SciTech Connect

    Reichel, Christian; Feldmann, Frank; Müller, Ralph; Hermle, Martin; Glunz, Stefan W.; Reedy, Robert C.; Lee, Benjamin G.; Young, David L.; Stradins, Paul

    2015-11-28

    Passivated contacts (poly-Si/SiO{sub x}/c-Si) doped by shallow ion implantation are an appealing technology for high efficiency silicon solar cells, especially for interdigitated back contact (IBC) solar cells where a masked ion implantation facilitates their fabrication. This paper presents a study on tunnel oxide passivated contacts formed by low-energy ion implantation into amorphous silicon (a-Si) layers and examines the influence of the ion species (P, B, or BF{sub 2}), the ion implantation dose (5 × 10{sup 14 }cm{sup −2} to 1 × 10{sup 16 }cm{sup −2}), and the subsequent high-temperature anneal (800 °C or 900 °C) on the passivation quality and junction characteristics using double-sided contacted silicon solar cells. Excellent passivation quality is achieved for n-type passivated contacts by P implantations into either intrinsic (undoped) or in-situ B-doped a-Si layers with implied open-circuit voltages (iV{sub oc}) of 725 and 720 mV, respectively. For p-type passivated contacts, BF{sub 2} implantations into intrinsic a-Si yield well passivated contacts and allow for iV{sub oc} of 690 mV, whereas implanted B gives poor passivation with iV{sub oc} of only 640 mV. While solar cells featuring in-situ B-doped selective hole contacts and selective electron contacts with P implanted into intrinsic a-Si layers achieved V{sub oc} of 690 mV and fill factor (FF) of 79.1%, selective hole contacts realized by BF{sub 2} implantation into intrinsic a-Si suffer from drastically reduced FF which is caused by a non-Ohmic Schottky contact. Finally, implanting P into in-situ B-doped a-Si layers for the purpose of overcompensation (counterdoping) allowed for solar cells with V{sub oc} of 680 mV and FF of 80.4%, providing a simplified and promising fabrication process for IBC solar cells featuring passivated contacts.

  5. Numerical Simulation Research in Plasma Technologies 4. PIC-MCC Simulation for Plasma Immersion Ion Implantation Processing

    NASA Astrophysics Data System (ADS)

    Miyagawa, Yoshiko

    Plasma Immersion Ion Implantation (PIII) has been developed as a method for high-flux implantation and conformal implantation on a complex shaped target. In PIII, a negative pulsed high voltage is applied to the target immersed in low-pressure high-density plasma. Then an ion sheath is formed around the target and energetic ions are implanted on the target surface. By increasing the plasma density, conformal implantation is possible. However, this process can not be easily realized for a complex shaped target, for instance which has a trench or holes with high aspectratios. In order to find the best condition in the process, it is very important to know the sheath shape around the target and the energy and flux distributions of implanted ions at each surface point. Plasma behavior in the PIII process has been simulated using “PEGASUS”.

  6. Implementation of KrF DBARCs for implant applications on advanced lithography nodes

    NASA Astrophysics Data System (ADS)

    Lowes, Joyce; Guerrero, Alice; Weigand, Michael; Washburn, Carlton; Stroud, Charlyn; Sharma, Shalini; Torres, David; Slezak, Mark; Dabbagh, Gary; Tang, Cherry

    2011-04-01

    Traditional implant layers are becoming increasingly complex in design and continuously pushing resolution limits lower. In response, developer-soluble bottom anti-reflective coatings (DBARCs) were introduced to meet these more challenging requirements. These DBARCs excelled over the traditional combination of single-layer resist and dyed resist/top anti-reflective coating (TARC). DBARCs offered the resolution and critical dimension (CD) control needed for the increasingly critical implant layers. Lithographic performance, focusing on CD control over topography and through-pitch behavior, demonstrated the inherent benefit of the DBARCs over the alternative solutions. Small-space residue testing showed the benefit of photosensitive (PS) DBARCs for cleanout of sub-100 nm trenches. A study of improved post-develop residue in various ion-implantation processes validated the use of new DBARC materials in implant layers.

  7. Controlled removal of ceramic surfaces with combination of ions implantation and ultrasonic energy

    DOEpatents

    Boatner, Lynn A.; Rankin, Janet; Thevenard, Paul; Romana, Laurence J.

    1995-01-01

    A method for tailoring or patterning the surface of ceramic articles is provided by implanting ions to predetermined depth into the ceramic material at a selected surface location with the ions being implanted at a fluence and energy adequate to damage the lattice structure of the ceramic material for bi-axially straining near-surface regions of the ceramic material to the predetermined depth. The resulting metastable near-surface regions of the ceramic material are then contacted with energy pulses from collapsing, ultrasonically-generated cavitation bubbles in a liquid medium for removing to a selected depth the ion-damaged near-surface regions containing the bi-axially strained lattice structure from the ceramic body. Additional patterning of the selected surface location on the ceramic body is provided by implanting a high fluence of high-energy, relatively-light ions at selected surface sites for relaxing the bi-axial strain in the near-surface regions defined by these sites and thereby preventing the removal of such ion-implanted sites by the energy pulses from the collapsing ultrasonic cavitation bubbles.

  8. 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.

  9. Towards p-type doping of ZnO by ion implantation

    SciTech Connect

    Coleman, V; Tan, H H; Jagadish, C; Kucheyev, S; Phillips, M; Zou, J

    2005-01-18

    Zinc oxide is a very attractive material for a range of optoelectronic devices including blue light-emitting diodes and laser diodes. Though n-type doping has been successfully achieved, p-type doing of ZnO is still a challenge that must be overcome before p-n junction devices can be realized. Ion implantation is widely used in the microelectronics industry for selective area doping and device isolation. Understanding damage accumulation and recrystallization processes is important for achieving selective area doping. In this study, As (potential p-type dopant) ion implantation and annealing studies were carried out. ZnO samples were implanted with high dose (1.4 x 10{sup 17} ions/cm{sup 2}) 300 keV As ions at room temperature. Furnace annealing of samples in the range of 900 C to 1200 C was employed to achieve recrystallization of amorphous layers and electrical activation of the dopant. Rutherford backscattering/channeling spectrometry, transmission electron microscopy and cathodolumiescence spectroscopy were used to monitor damage accumulation and annihilation behavior in ZnO. Results of this study have significant implications for p-type doing of ZnO by ion implantation.

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

    SciTech Connect

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

    2012-11-06

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

  11. 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.

  12. Influence of ion implantation on the magnetic properties of thin FeCo films

    SciTech Connect

    Gupta, Ratnesh; Han, K.-H.; Lieb, K.P.; Mueller, G.A.; Schaaf, P.; Zhang, K.

    2005-04-01

    Modifications of 73-nm-thick polycrystalline FeCo films by magnetic-field-assisted implantation of Ne, Xe, and Au ions have been investigated. For magnetic characterization, the longitudinal magneto-optic Kerr effect and magnetic force microscopy (MFM) in the remanent state have been used, while structural information has been gained from glancing-angle x-ray diffraction and Rutherford backscattering spectroscopy. The irradiated films show a soft-magnetic behavior with large magnetic anisotropy. The Ne ions initially induce an increasing coercivity, possibly due to radiation defects accumulated during the ion implantation, while higher Ne fluences anneal out the defects and reduce the coercivity. For the heavy ions the deposited energy density is high enough to reduce the coercivity at small fluences and then to increase it slightly for increasing fluence. Correlations between the magnetic anisotropy, coercivity and the ion species and fluence have been established. The MFM pictures feature the largest changes in the case of Au ions. The magnetic anisotropy reflects the interplay between magnetocrystalline and magnetostrictive forces. For heavier ions and large fluences, the direction of the in-plane magnetic easy axis follows the orientation of the external magnetic field present during implantation.

  13. Local structural properties of Co-ion-implanted ZnO nanorods

    NASA Astrophysics Data System (ADS)

    Park, C. I.; Jin, Zhenlan; Jeong, E. S.; Hwang, I. H.; Han, S. W.

    2013-12-01

    We examined the local structural properties around Co and Zn ions in Co-ion-implanted ZnO nanorods by using an X-ray absorption fine structure (XAFS) analysis. Vertically-aligned ZnO nanorods were synthesized on Al2O3 substrates by using a catalyst-free metal-organic chemicalvapor deposition. Co ions (Co+ and Co2+) with energies of 50 and 100 keV and fluxes of 1013 and 1015 particles/cm2 were implanted in the ZnO nanorods, and the ion-implanted ZnO nanorods were annealed at 400-650°C. X-ray absorption near edge structure (XANES) analyses demonstrated that the chemical valence state of the Co ions were mostly 2+. An extended XAFS (EXAFS) analysis revealed that the Co ions were mostly substituted at the Zn sites of ZnO nanorods at a Coion flux of 1015 particles/cm2. However, at a flux of 1013 particles/cm2, Co ions formed Co-O and Co-Co clusters. These results were in contrast to the Co distribution in Co-added ZnO predicted by using a Monte Carlo method.

  14. A Novel Percutaneous Electrode Implant for Improving Robustness in Advanced Myoelectric Control.

    PubMed

    Hahne, Janne M; Farina, Dario; Jiang, Ning; Liebetanz, David

    2016-01-01

    Despite several decades of research, electrically powered hand and arm prostheses are still controlled with very simple algorithms that process the surface electromyogram (EMG) of remnant muscles to achieve control of one prosthetic function at a time. More advanced machine learning methods have shown promising results under laboratory conditions. However, limited robustness has largely prevented the transfer of these laboratory advances to clinical applications. In this paper, we introduce a novel percutaneous EMG electrode to be implanted chronically with the aim of improving the reliability of EMG detection in myoelectric control. The proposed electrode requires a minimally invasive procedure for its implantation, similar to a cosmetic micro-dermal implant. Moreover, being percutaneous, it does not require power and data telemetry modules. Four of these electrodes were chronically implanted in the forearm of an able-bodied human volunteer for testing their characteristics. The implants showed significantly lower impedance and greater robustness against mechanical interference than traditional surface EMG electrodes used for myoelectric control. Moreover, the EMG signals detected by the proposed systems allowed more stable control performance across sessions in different days than that achieved with classic EMG electrodes. In conclusion, the proposed implants may be a promising interface for clinically available prostheses. PMID:27065783

  15. A Novel Percutaneous Electrode Implant for Improving Robustness in Advanced Myoelectric Control

    PubMed Central

    Hahne, Janne M.; Farina, Dario; Jiang, Ning; Liebetanz, David

    2016-01-01

    Despite several decades of research, electrically powered hand and arm prostheses are still controlled with very simple algorithms that process the surface electromyogram (EMG) of remnant muscles to achieve control of one prosthetic function at a time. More advanced machine learning methods have shown promising results under laboratory conditions. However, limited robustness has largely prevented the transfer of these laboratory advances to clinical applications. In this paper, we introduce a novel percutaneous EMG electrode to be implanted chronically with the aim of improving the reliability of EMG detection in myoelectric control. The proposed electrode requires a minimally invasive procedure for its implantation, similar to a cosmetic micro-dermal implant. Moreover, being percutaneous, it does not require power and data telemetry modules. Four of these electrodes were chronically implanted in the forearm of an able-bodied human volunteer for testing their characteristics. The implants showed significantly lower impedance and greater robustness against mechanical interference than traditional surface EMG electrodes used for myoelectric control. Moreover, the EMG signals detected by the proposed systems allowed more stable control performance across sessions in different days than that achieved with classic EMG electrodes. In conclusion, the proposed implants may be a promising interface for clinically available prostheses. PMID:27065783

  16. 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.

  17. Empirical modeling of the cross section of damage formation in ion implanted III-V semiconductors

    SciTech Connect

    Wendler, E.; Wendler, L.

    2012-05-07

    In this letter, the cross section of damage formation per individual ion is measured for III-V compound semiconductors ion implanted at 15 K, applying Rutherford backscattering spectrometry. An empirical model is proposed that explains the measured cross sections in terms of quantities representing the primary energies deposited in the displacement of lattice atoms and in electronic interactions. The resulting formula allows the prediction of damage formation for low temperatures and low ion fluences in these materials and can be taken as a starting point for further quantitative modeling of damage formation including secondary effects such as temperature and ion flux.

  18. Initial operation of a large-scale Plasma Source Ion Implantation experiment

    SciTech Connect

    Wood, B.P.; Henins, I.; Gribble, R.J.; Reass, W.A.; Faehl, R.J.; Nastasi, M.A.; Rej, D.J.

    1993-10-01

    In Plasma Source Ion Implantation (PSII), a workpiece to be implanted is immersed in a weakly ionized plasma and pulsed to a high negative voltage. Plasma ions are accelerated toward the workpiece and implanted in its surface. Experimental PSII results reported in the literature have been for small workpieces. A large scale PSII experiment has recently been assembled at Los Alamos, in which stainless steel and aluminum workpieces with surface areas over 4 m{sup 2} have been implanted in a 1.5 m-diameter, 4.6 m-length cylindrical vacuum chamber. Initial implants have been performed at 50 kV with 20 {mu}s pulses of 53 A peak current, repeated at 500 Hz, although the pulse modulator will eventually supply 120 kV pulses of 60 A peak current at 2 kHz. A 1,000 W, 13.56 MHz capacitively-coupled source produces nitrogen plasma densities in the 10{sup 15} m{sup {minus}3} range at neutral pressures as low as 0.02 mtorr. A variety of antenna configurations have been tried, with and without axial magnetic fields of up to 60 gauss. Measurements of sheath expansion, modulator voltage and current, and plasma density fill-in following a pulse are presented. The authors consider secondary electron emission, x-ray production, workpiece arcing, implant conformality, and workpiece and chamber heating.

  19. New advanced surface modification technique: titanium oxide ceramic surface implants: long-term clinical results

    NASA Astrophysics Data System (ADS)

    Szabo, Gyorgy; Kovacs, Lajos; Barabas, Jozsef; Nemeth, Zsolt; Maironna, Carlo

    2001-11-01

    The purpose of this paper is to discuss the background to advanced surface modification technologies and to present a new technique, involving the formation of a titanium oxide ceramic coating, with relatively long-term results of its clinical utilization. Three general techniques are used to modify surfaces: the addition or removal of material and the change of material already present. Surface properties can also be changed without the addition or removal of material, through the laser or electron beam thermal treatment. The new technique outlined in this paper relates to the production of a corrosion-resistant 2000-2500 A thick, ceramic oxide layer with a coherent crystalline structure on the surface of titanium implants. The layer is grown electrochemically from the bulk of the metal and is modified by heat treatment. Such oxide ceramic-coated implants have a number of advantageous properties relative to implants covered with various other coatings: a higher external hardness, a greater force of adherence between the titanium and the oxide ceramic coating, a virtually perfect insulation between the organism and the metal (no possibility of metal allergy), etc. The coated implants were subjected to various physical, chemical, electronmicroscopic, etc. tests for a qualitative characterization. Finally, these implants (plates, screws for maxillofacial osteosynthesis and dental root implants) were applied in surgical practice for a period of 10 years. Tests and the experience acquired demonstrated the good properties of the titanium oxide ceramic-coated implants.

  20. 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