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Atomic scale modeling of boron transient diffusion in silicon

Description: We presents results from a predictive atomic level simulation of Boron diffusion in Silicon under a wide variety of implant and annealing conditions. The parameters for this simulation have been extracted from first principle approximation models and molecular dynamics simulations. The results are compared with experiments showing good agreement in all cases. The parameters and reactions used have been implemented into a continuum-level model simulator.
Date: June 17, 1998
Creator: Caturla, M. J.; Diaz de la Rubia, T.; Foad, M.; Giles, M.; Johnson, M. D.; Law, M. et al.
Partner: UNT Libraries Government Documents Department

Atomic scale simulations of arsenic ion implantation and annealing in silicon

Description: We present results of multiple-time-scale simulations of 5, 10 and 15 keV low temperature ion implantation of arsenic on silicon (100), followed by high temperature anneals. The simulations start with a molecular dynamics (MD) calculation of the primary state of damage after 10ps. The results are then coupled to a kinetic Monte Carlo (MC) simulation of bulk defect diffusion and clustering. Dose accumulation is achieved considering that at low temperatures the damage produced in the lattice is stable. After the desired dose is accumulated, the system is annealed at 800{degrees}C for several seconds. The results provide information on the evolution for the damage microstructure over macroscopic length and time scales and affords direct comparison to experimental results. We discuss the database of inputs to the MC model and how it affects the diffusion process.
Date: January 23, 1995
Creator: Caturla, M.J.; Diaz de la Rubia, T. & Jaraiz, M.
Partner: UNT Libraries Government Documents Department

Basic Research Needs for Advanced Nuclear Systems. Report of the Basic Energy Sciences Workshop on Basic Research Needs for Advanced Nuclear Energy Systems, July 31-August 3, 2006

Description: The global utilization of nuclear energy has come a long way from its humble beginnings in the first sustained nuclear reaction at the University of Chicago in 1942. Today, there are over 440 nuclear reactors in 31 countries producing approximately 16% of the electrical energy used worldwide. In the United States, 104 nuclear reactors currently provide 19% of electrical energy used nationally. The International Atomic Energy Agency projects significant growth in the utilization of nuclear power over the next several decades due to increasing demand for energy and environmental concerns related to emissions from fossil plants. There are 28 new nuclear plants currently under construction including 10 in China, 8 in India, and 4 in Russia. In the United States, there have been notifications to the Nuclear Regulatory Commission of intentions to apply for combined construction and operating licenses for 27 new units over the next decade. The projected growth in nuclear power has focused increasing attention on issues related to the permanent disposal of nuclear waste, the proliferation of nuclear weapons technologies and materials, and the sustainability of a once-through nuclear fuel cycle. In addition, the effective utilization of nuclear power will require continued improvements in nuclear technology, particularly related to safety and efficiency. In all of these areas, the performance of materials and chemical processes under extreme conditions is a limiting factor. The related basic research challenges represent some of the most demanding tests of our fundamental understanding of materials science and chemistry, and they provide significant opportunities for advancing basic science with broad impacts for nuclear reactor materials, fuels, waste forms, and separations techniques. Of particular importance is the role that new nanoscale characterization and computational tools can play in addressing these challenges. These tools, which include DOE synchrotron X-ray sources, neutron sources, nanoscale science research centers, ...
Date: October 1, 2006
Creator: Roberto, J.; Diaz de la Rubia, T.; Gibala, R.; Zinkle, S.; Miller, J.R.; Pimblott, S. et al.
Partner: UNT Libraries Government Documents Department

Basic Research Needs for Materials Under Extreme Environments. Report of the Basic Energy Sciences Workshop on Materials Under Extreme Environments, June 11-13, 2007

Description: To evaluate the potential for developing revolutionary new materials that will meet demanding future energy requirements that expose materials to environmental extremes.
Date: February 1, 2008
Creator: Wadsworth, J.; Crabtree, G. W.; Hemley, R. J.; Falcone, R.; Robertson, I.; Stringer, J. et al.
Partner: UNT Libraries Government Documents Department

Contributions of the National Ignition Facility to the development of inertial fusion energy. Revision 1

Description: The Department of Energy is proposing to construct the National Ignition Facility (NIF) to embark on a program to achieve ignition and modest gain in the laboratory early in the next century. The NM will use a {ge}1.8-MJ, 0.35-mm laser with 192 independent beams, a fifty-fold increase over the energy of the Nova laser. System performance analyses suggest yields as great as 20 MJ may be achievable. NIF will conduct more than 600 shots per year. The benefits of a micro-fusion capability in the laboratory include: Essential contributions to defense programs, resolution of important Inertial Fusion Energy issues, and unparalleled conditions of energy density for basic science and technology research. We have begun to consider the role the National Ignition Facility will fill in the development of Inertial Fusion Energy. While the achievement of ignition and gain speaks for itself in terms of its impact on developing IFE, we believe there are areas of IFE development, such as fusion power technology, IFE target design and fabrication, and understanding chamber dynamics, that would significantly benefit from NIF experiments. In the area of IFE target physics, ion targets will be designed using the NIF laser, and feasibility of high gain targets will be confirmed. Target chamber dynamics experiments will benefit from x-ray and debris energies that mimic in-IFE-chamber conditions. Fusion power technology will benefit from using single-shot neutron yields to measure spatial distribution of neutron heating, activation, and tritium breeding in relevant materials. IFE target systems will benefit from evaluating low-cost target fabrication techniques by testing such targets on NIF.
Date: October 1, 1994
Creator: Tobin, M.; Logan, G.; Diaz De La Rubia, T.; Schrock, V.; Schultz, K.; Tokheim, R. et al.
Partner: UNT Libraries Government Documents Department

Dimensional Stability and Microstructure Evolution in Irradiated Systems with Complex Kinetics

Description: We use a combination of molecular dynamics and kinetic Monte Carlo simulations to explore the role of temperature and dose rate on damage accumulation in a model system with complex kinetics. We describe the accumulation of He-vacancy (HeV) complexes as well as vacancy and interstitial clusters as a function of irradiation temperature, dose, and dose rate. We show that nucleation of stable HeV complexes (voids and bubbles) at low temperature and flux takes place at extremely low doses. We also describe the effect of temperature on the HeV complex size distribution and show that growth beyond a critical nucleation size is not possible in this system at temperatures above 300 K for dose rates smaller than 10{sup -8} dpa/s. We further demonstrate that a temperature shift of 25 K per decade of flux scales the dose rate dependence of He-vacancy complex (voids and bubbles) accumulation when irradiation is carried out to low doses (0.03-0.06 dpa) at temperatures between 150 K and 300 K and dose rates of 10{sup -6}, 10{sup -7}, l0{sup -8}, and 10{sup -9} dpa/s. The results provide an atomistic description of microstructure evolution including void nucleation and the early stages of growth, and should be useful in designing and interpreting accelerated aging experiments.
Date: October 11, 1999
Creator: Diaz de la Rubia, T.; Caturla, M. & Fluss, M.J.
Partner: UNT Libraries Government Documents Department

Dose rate effects during damage accumulation in silicon

Description: We combine molecular dynamics and Monte Carlo simulations to study damage accumulation and dose rate effects during irradiation of Silicon. We obtain the initial stage of the damage produced by heavy and light ions using classical molecular dynamics simulations. While heavy ions like As or Pt induce amorphization by single ion impact, light ions like B only produce point defects or small clusters of defects. The amorphous pockets generated by heavy ions are stable below room temperature and recrystallize at temperatures below the threshold for recrystallization of a planar amorphous-crystalline interface. The damage accumulation during light ion irradiation is simulated using a Monte Carlo model for defect diffusion. In this approach, we study the damage in the lattice as a function of dose and dose rate. A strong reduction in the total number of defects left in the lattice is observed for lower dose rates.
Date: January 1, 1997
Creator: Caturla, M.J. & Diaz de la Rubia, T.
Partner: UNT Libraries Government Documents Department

Dynamics and structure of energetic displacement cascades

Description: This paper summarizes recent progress in the understanding of energetic displacement cascades and the primary state of damage in metals. On the theoretical side, the availability of supercomputers has greatly enhanced our ability to simulate cascades by molecular dynamics. Recent application of this simulation technique to Cu and Ni provides new insight into the dynamics of cascade processes. On the experimental side, new data on ion beam mixing and in situ electron microscopy studies of ion damage at low temperatures reveal the role of the thermodynamic properties of the material on cascade dynamics and structure. 38 refs., 9 figs.
Date: December 1, 1987
Creator: Averback, R.S.; Diaz de la Rubia, T. & Benedek, R.
Partner: UNT Libraries Government Documents Department

Effect of ramp rate and annealing temperature on boron transient diffusion in implanted silicon: kinetic Monte Carlo simulations

Description: We present results of recent kinetic Monte Carlo simulations of the effect of annealing time and ramp rate on boron transient enhanced diffusion (BTED) in low energy ion implanted silicon. The simulations use a database of defect and dopant energetics derived from first principle calculations. We discuss the complete atomistic details of defect and dopant clustering during the anneals, and the dependence of boron TED on ramp rate. The simulations provide a complete time history of the evolution of the active boron fraction during the anneal for a wide variety of conditions. We also studied the lateral spreading of the boron during the annealing for two different conditions, furnace anneal and ramp anneal.
Date: June 17, 1998
Creator: Caturla, M. J.; Diaz de la Rubia, T. & Foad, M.
Partner: UNT Libraries Government Documents Department

Interaction between point defects and edge dislocation in BCC iron

Description: We present results of atomistic simulations of the interaction between self interstitial atoms and vacancies with edge dislocations in BCC iron. The calculations are carried out using molecular dynamics with an energy minimization scheme based on the quasi-Newton approach and use the Finnis-Sinclair interatomic potential for BCC iron developed by Ackland et al. Large anisotropy in the strain field of self interstitials is observed and it causes strong interaction with edge dislocations even when the defect is located on the dislocation glide plane. For vacancies, the relaxation volume is smaller and much more isotropic, which results in a far weaker interaction with the dislocation. A temperature dependent capture radius for vacancies and self interstitials is extracted from the simulations. The difference between the capture radii of vacancies and self interstitials is used to define the sink strength of the dislocation. Large deviations are observed from the predictions of elasticity based on treating point defects as isotropic dilatational centers. Further, the capture radius of edge dislocations in BCC iron is observed to be small and is of the order of l-3 nm for self interstitials.
Date: October 12, 1998
Creator: Diaz de la Rubia, T. & Shastry, V.
Partner: UNT Libraries Government Documents Department

Interactions of energetic particles and clusters with solids

Description: Ion beams are being applied for surface modifications of materials in a variety of different ways: ion implantation, ion beam mixing, sputtering, and particle or cluster beam-assisted deposition. Fundamental to all of these processes is the deposition of a large amount of energy, generally some keV's, in a localized area. This can lead to the production of defects, atomic mixing, disordering and in some cases, amorphization. Recent results of molecular dynamics computer simulations of energetic displacement cascades in Cu and Ni with energies up to 5 keV suggest that thermal spikes play an important role in these processes. Specifically, it will be shown that many aspects of defect production, atomic mixing and cascade collapse'' can be understood as a consequence of local melting of the cascade core. Included in this discussion will be the possible role of electron-phonon coupling in thermal spike dynamics. The interaction of energetic clusters of atoms with solid surfaces has also been studied by molecular dynamics simulations. this process is of interest because a large amount of energy can be deposited in a small region and possibly without creating point defects in the substrate or implanting cluster atoms. The simulations reveal that the dynamics of the collision process are strongly dependent on cluster size and energy. Different regimes where defect production, local melting and plastic flow dominate will be discussed. 43 refs., 7 figs.
Date: December 1, 1990
Creator: Averback, R.S.; Hsieh, Horngming (Illinois Univ., Urbana, IL (USA). Dept. of Materials Science and Engineering); Diaz de la Rubia, T. (Lawrence Livermore National Lab., CA (USA)) & Benedek, R. (Argonne National Lab., IL (USA))
Partner: UNT Libraries Government Documents Department

Ion beam mixing in binary amorphous metallic alloys. [Cu-Er; Ni-Ti]

Description: Ion beam mixing (IM) was measured in homogeneous amorphous metallic alloys of Cu-Er and Ni-Ti as a function of temperature using tracer impurities, i.e., the so-called ''marker geometry''. In Cu-Er, a strong temperature dependence in IM was observed between 80 and 373K, indicating that radiation-enhanced diffusion mechanisms are operative in this metallic glass. Phase separation of the Cu-Er alloy was also observed under irradiation as Er segregated to the vacuum and SiO2 interfaces of the specimen. At low-temperatures, the amount of mixing in amorphous Ni-Ti is similar to that in pure Ni or Ti, but it is much greater in Cu-Er than in either Cu or Er.
Date: December 1, 1985
Creator: Hahn, H.; Averback, R.S.; Diaz de la Rubia, T. & Okamoto, P.R.
Partner: UNT Libraries Government Documents Department

Linking ab initio energetics to experiment: kinetic Monte Carlo simulation of transient enhanced diffusion of B in Si

Description: We have developed a kinetic Monte Carlo (kMC) simulator that links atomic migration and binding energies determined primarily from first principles calculations to macroscopic phenomena and laboratory time scales. Input for the kMC simulation is obtained from a combination of ab initio planewave pseudopotential calculations, molecular dynamics simulations, and experimental data. The simulator is validated against an extensive series of experimental studies of the diffusion of B spikes in self-implanted Si. The implant energy, dose, and dose rate, as well as the detailed thermal history of the sample, are included. Good agreement is obtained with the experimental data for temperatures between 750 and 950 C and times from 15 to 255 s. At 1050o C we predict too little diffusion after 105 s compared to experiment: apparently, some mechanism which is not adequately represented by our model becomes important at this temperature. Below 1050o C, the kMC simulation produces a complete description over macroscopic time scales of the atomic level diffusion and defect reaction phenomena that operate during the anneals. This simulator provides a practical method for predicting technologically interesting phenomena, such as transient enhanced diffusion of B, over a wide range of conditions, using energetics determined from first-principles approaches.
Date: December 16, 1998
Creator: Caturla, M. J.; Diaz de la Rubia, T.; Griffin, P. B.; Johnson, M. C.; Theiss, S. & Ural, A.
Partner: UNT Libraries Government Documents Department

LLNL's program on multiscale modeling of polycrystal plasticity

Description: At LLNL a multiscale modeling program based on information-passing has been established for modeling the strength properties of a body-centered-cubic metal (tantalum) ,. under conditions of extreme plastic deformation. The plastic deformation experienced by an explosively-formed shaped-charge jet is an example of �extreme deformation�. The shaped charge liner material undergoes high strain rate deformation at high hydrostatic pressure. The constitutive model for flow stress, which describes the deformation, is highly dependent on pressure, temperature, and strain-rate. Current material models can not be extrapolated to these extreme conditions because the underlying mechanisms of plastic deformation are poorly reflected in the models and laboratory experiments are limited to pressures orders of magnitude less than actual pressures. This disparity between actual deformation conditions and those that can be attained in laboratory experiments is the principle motivation behind the multiscale modeling program. The fundamental elements of LLNL� s multiscale modeling program are distinct models at the atomistic, microscale and mesoscale/continuum length scales. The information that needs to be passed from the lower to higher length scales has been carefully defined to bound the levels of effort required to ''bridge'' length scales. Information that needs to be generated by the different simulations has been specified by a multidisciplinary steering group comprised of physicists, materials scientists and engineers. The ultimate goal of the program is to provide critical information on strength properties to be used in continuum computer code simulations. The technical work-plan involves three principle areas which are highly coupled: 1) simulation development, 2) deformation experiments and 3) characterizations of deformed crystals. The three work areas are presented which provide examples of the progress of LLNL's program.
Date: April 27, 1998
Creator: Diaz De La Rubia, T.; Holmes, N. H.; King, W. E.; Lassila, D. H.; Moriarty, J. A. & Nikkel, D. J.
Partner: UNT Libraries Government Documents Department

Mechanisms of cascade collapse

Description: The spontaneous collapse of energetic displacement cascades in metals into vacancy dislocation loops has been investigated by molecular dynamics (MD) computer simulation and transmission electron microscopy (TEM). Simulations of 5 keV recoil events in Cu and Ni provide the following scenario of cascade collapse: atoms are ejected from the central region of the cascade by replacement collision sequences; the central region subsequently melts; vacancies are driven to the center of the cascade during resolidification where they may collapse into loops. Whether or not collapse occurs depends critically on the melting temperature of the metal and the energy density and total energy in the cascade. Results of TEM are presented in support of this mechanism. 14 refs., 4 figs., 1 tab.
Date: December 1, 1988
Creator: Diaz de la Rubia, T.; Smalinskas, K.; Averback, R.S.; Robertson, I.M.; Hseih, H. & Benedek, R.
Partner: UNT Libraries Government Documents Department

Mechanisms of defect production and atomic mixing in high energy displacement cascades: A molecular dynamics study

Description: We have performed molecular dynamics computer simulation studies of displacement cascades in Cu at low temperature. For 25 keV recoils we observe the splitting of a cascade into subcascades and show that cascades in Cu may lead to the formation of vacancy and interstitial dislocation loops. We discuss a new mechanism of defect production based on the observation of interstitial prismatic dislocation loop punching from cascades at 10 K. We also show that below the subcascade threshold, atomic mixing in the cascade is recoil-energy dependent and obtain a mixing efficiency that scales as the square root of the primary recoil energy. 44 refs., 12 figs.
Date: June 5, 1991
Creator: Diaz de la Rubia, T. & Guinan, M.W.
Partner: UNT Libraries Government Documents Department

Modeling and Computer Simulation: Molecular Dynamics and Kinetic Monte Carlo

Description: Recent years have witnessed tremendous advances in the realistic multiscale simulation of complex physical phenomena, such as irradiation and aging effects of materials, made possible by the enormous progress achieved in computational physics for calculating reliable, yet tractable interatomic potentials and the vast improvements in computational power and parallel computing. As a result, computational materials science is emerging as an important complement to theory and experiment to provide fundamental materials science insight. This article describes the atomistic modeling techniques of molecular dynamics (MD) and kinetic Monte Carlo (KMC), and an example of their application to radiation damage production and accumulation in metals. It is important to note at the outset that the primary objective of atomistic computer simulation should be obtaining physical insight into atomic-level processes. Classical molecular dynamics is a powerful method for obtaining insight about the dynamics of physical processes that occur on relatively short time scales. Current computational capability allows treatment of atomic systems containing as many as 10{sup 9} atoms for times on the order of 100 ns (10{sup -7}s). The main limitation of classical MD simulation is the relatively short times accessible. Kinetic Monte Carlo provides the ability to reach macroscopic times by modeling diffusional processes and time-scales rather than individual atomic vibrations. Coupling MD and KMC has developed into a powerful, multiscale tool for the simulation of radiation damage in metals.
Date: October 10, 2000
Creator: Wirth, B.D.; Caturla, M.J. & Diaz de la Rubia, T.
Partner: UNT Libraries Government Documents Department

Modeling defect production in high energy collision cascades

Description: A multi-model approach roach (MMA) to simulating defect production processes at the atomic scale is described that incorporates molecular dynamics (MD), binary collision approximation (BCA) calculations and stochastic annealing simulations. The central hypothesis of the MMA is that the simple, fast computer codes capable of simulating large numbers of high energy cascades (e.g., BCA codes) can be made to yield the correct defect configurations when their parameters are calibrated using the results of the more physically realistic MD simulations. The calibration procedure is investigated using results of MD simulations of 25 keV cascades in copper. The configurations of point defects are extracted from the MD cascade simulations at the end of the collisional phase, similar to the information obtained with a binary collision model. The MD collisional phase defect configurations are used as input to the ALSOME annealing simulation code, and values of the ALSOME quenching parameters are determined that yield the best fit to the post-quenching defect configurations of the MD simulations.
Date: December 1, 1993
Creator: Heinisch, H. L.; Singh, B. N. & Diaz de la Rubia, T.
Partner: UNT Libraries Government Documents Department

Modeling of ion implantation and diffusion in Si

Description: Classical molecular dynamics simulations are used to study damage produced during implantation of semiconductors with different ion masses and energies between 1-25 keV. The time scale for these simulations is only on the order of ns, and therefore problems like transient enhanced diffusion of dopants or formation of extended defects can not be studied with these models. Monte Carlo simulations, including as input the results obtained from molecular dynamics calculations, are used to extend the simulation time, and in particular, to study processes like ion implantation and defects diffusion in semiconductors. As an example, we show results for diffusion of the damage produced by implantation of Si with 5 keV Xe ions at low doses. Results of the simulations are compared with experiments in order to validate the model.
Date: September 1, 1996
Creator: Caturla, M-J; Diaz de la Rubia, T. & Bedrossian, P.J.
Partner: UNT Libraries Government Documents Department

A molecular dynamics simulation study of defect production in vanadium

Description: We performed molecular dynamics simulations to investigate the process of defect production in pure vanadium. The interaction of atoms was described by the EAM interatomic potential modified at short range to merge smoothly with the universal potential for description of the high energy recoils in cascades. The melting point of this EAM model of vanadium was found to be consistent with the experimental melting temperature. The threshold energies of displacement events in the model system are also consistent with experimental minimum threshold in vanadium, and its average was found to be 44 eV. We evaluated the efficiencies of defect production in the displacement events initiated by recoils with kinetic energy up to 5 keV, and found that the probability of cluster formation is smaller than that of simulated events in fcc metals reported in the literature.
Date: January 23, 1995
Creator: Morishita, K. & Diaz de la Rubia, T.
Partner: UNT Libraries Government Documents Department

Molecular dynamics studies of radiation effects in silicon carbide

Description: We discuss results of molecular dynamics computer simulation studies of 3 keV and 5 keV displacement cascades in {beta}-SIC, and compare them to results of 5 keV cascades in pure silicon. The SiC simulations are performed with the Tersoff potential. For silicon we use the Stillinger-Weber potential. Simulations were carried out for Si recoils in 3 dimensional cubic computational cells With periodic boundary conditions and up to 175,616 atoms. The cascade lifetime in SiC is found to be extremely short. This, combined with the high melting temperature of SiC, precludes direct lattice amorphization during the cascade. Although large disordered regions result, these retain their basic crystalline structure. These results are in contrast with observations in pure silicon where direct-impact amorphization from the cascade is seen to take place. The SiC results also show anisotropy in the number of Si and C recoils as well as in the number of replacements in each sublattice. Details of the damage configurations obtained will be discussed.
Date: January 1, 1995
Creator: Diaz de la Rubia, T.; Caturla, M.J. & Tobin, M.
Partner: UNT Libraries Government Documents Department

Molecular dynamics studies of the primary state of radiation damage

Description: This paper summarizes recent progress in the understanding of energetic displacement cascades in metals achieved with the molecular-dynamics (MD) simulation technique. Recoil events with primary-knock-on-atom (PKA) energies up to 5 keV were simulated in Cu and Ni. The initial development of displacement cascades was similar in both metals, with replacement collision sequences providing the most efficient mechanism for the separation of interstitials and vacancies. The thermal-spike behavior in these metals, however, is quite different; Cu cascades are characterized by lower defect production and greater atomic disordering than those in Ni. The thermal spike significantly influences various other properties of cascades, such as total defect production and defect clustering. 32 refs., 7 figs., 2 tabs.
Date: December 1988
Creator: Diaz de la Rubia, T.; Averback, R. S.; Robertson, I. M. & Benedek, R.
Partner: UNT Libraries Government Documents Department

Periodic boundary conditions for three dimensional dislocation dynamics

Description: The boundary conditions in three dimensional Dislocation Dynamics (DD) simulations have always been a matter of concern. Two types of boundary conditions, quasi-free-surface and reflection boundaries are currently being used by groups in Grenoble, France and Pullman, Washington. In this paper, we present a mathematical transformation that enables simulations of dislocation evolution processes in single crystals using periodic boundary conditions (PBCs). The idea is graphically demonstrated with transformation matrices given for BCC crystal systems. Extension to other crystal structures is also discussed. Comparing to the existing boundary conditions, the new approach (1) balances the dislocation flux in and out of a computational cell; and (2) does not require artificial termination of dislocations in the bulk. 3 refs., 2 figs., 1 tab.
Date: January 1, 1997
Creator: Huang, H., Diaz de la Rubia, T.
Partner: UNT Libraries Government Documents Department

The threshold energy for defect production in SiC: A molecular dynamic study

Description: We discuss the results of molecular dynamics computer simulation studies of the threshold energy for defect production in {beta}-SiC. The simulations are performed with the Tersoff potential for SiC which provides accurate values of many of its defect properties. In addition, we show that it properly describes the melting behavior of SiC. Simulations were carried out for Si and C recoils in 3 dimensional cubic computational cells with periodic boundary conditions and up to 4096 atoms. The results show anisotropy in the threshold for Si and C recoils as well as for the recoil direction. The lowest threshold is 25 eV for C recoils along [111] and the highest is 85 eV for Si recoils along [110]. Details of the defect configurations obtained will be discussed.
Date: October 1, 1993
Creator: Wong, J.; Diaz de la Rubia, T.; Guinan, M. W.; Tobin, M.; Perlado, J. M.; Perez, A. S. et al.
Partner: UNT Libraries Government Documents Department