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Stopping and Range of Ions in Matter (SRIM) is a group of computer programs which calculate interaction of ions with matter; the core of SRIM is a program Transport of ions in matter (TRIM). SRIM is very popular in the ion implantation research and technology community and also used widely in other branches of radiation material science. The programs were developed by James F. Ziegler and Jochen P. Biersack around 1983 〔J. P. Biersack and L. G. Haggmark. A Monte Carlo computer program for the transport of energetic ions in amorphous targets. Nucl. Instr. Meth., 174:257, 1980〕〔J. F. Ziegler, J. P. Biersack, and U. Littmark. The Stopping and Range of Ions in Matter. Pergamon, New York, 1985.〕 and are being continuously upgraded with the major changes occurring approximately every five years.〔(【引用サイトリンク】title=Particle interactions with matter )〕 SRIM is based on a Monte Carlo simulation method, namely the binary collision approximation 〔M. T. Robinson and Ian M. Torrens. Computer simulation of atomic-displacement cascades in solids in the binary-collision approximation. Phys. Rev. B, 9(12):5008, 1974.〕〔Gary Was. Fundamentals of Radiation Materials Science. Springer, 2012.〕〔R. Smith (ed.). Atomic & ion collisions in solids and at surfaces: theory, simulation and applications. Cambridge University Press, Cambridge, UK, 1997〕 with a random selection of the impact parameter of the next colliding ion. As the input parameters, it needs the ion type and energy (in the range 10 eV – 2 GeV) and the material of one or several target layers. As the output, it lists or plots * the three-dimensional distribution of the ions in the solid and its parameters, such as penetration depth, its spread along the ion beam (called straggle) and perpendicular to it, all target atom cascades in the target are followed in detail; * concentration of vacancies, sputtering rate, ionization, and phonon production in the target material; * energy partitioning between the nuclear and electron losses, energy deposition rate; The programs are made so they can be interrupted at any time, and then resumed later. They have a very easy-to-use user interface and built-in default parameters for all ions and materials. Another part of the software allows calculating the electronic stopping power of any ion in any material (including gaseous targets) based on an averaging parametrization of a vast range of experimental data.〔 Those features made SRIM immensely popular. However, it doesn't take account of the crystal structure nor dynamic composition changes in the material that severely limits its usefulness in some cases. Other approximations of the program include * binary collision (i.e. the influence of neighboring atoms is neglected); * The material is fully amorphous, i.e. description of ion channeling effects〔M. T. Robinson and O. S. Oen. The channeling of energetic atoms in crystal lattices. Appl. Phys. Lett., 2(4):30, 1963.〕 is not possible. * recombination of knocked off atoms (interstitials) with the vacancies,〔R. S. Averback and T. Diaz de la Rubia. Displacement damage in irradiated metals and semiconductors. In H. Ehrenfest and F. Spaepen, editors, Solid State Physics, volume 51, pages 281--402. Academic Press, New York, 1998.〕 an effect known to be very important in heat spikes in metals,〔K. Nordlund, M. Ghaly, R. S. Averback, M. Caturla, T. Diaz de la Rubia, and J. Tarus. Defect production in collision cascades in elemental semiconductors and fcc metals. Phys. Rev. B, 57(13):7556--7570, 1998〕 is neglected; * There is no description of defect clustering and irradiation-induced amorphization, even though the former occurs in most materials 〔P. Partyka, Y. Zhong, K. Nordlund, R. S. Averback, I. K. Robinson, and P. Ehrhart. Grazing incidence diffuse x-ray scattering investigation of the properties of irradiation-induced point defects in silicon. Phys. Rev. B, 64:235207, 2002.〕〔M. A. Kirk, I. M. Robertson, M. L. Jenkins, C. A. English, T. J. Black, and J. S. Vetrano. The collapse of defect cascades to dislocation loops. J. Nucl. Mater., 149:21, 1987.〕 and the latter is very important in semiconductors.〔M. O. Ruault, J. Chaumont, J. M. Penisson, and A. Bourret. High resolution and in situ investigation of defects in Bi-irradiated Si Phil. Mag. A, 50(5):667, 1984.〕 * The electronic stopping power is an averaging fit to a large number of experiments.〔 * the interatomic potential as a universal form which is an averaging fit to quantum mechanical calculations.〔 * the target atom which reaches the surface can leave the surface (be sputtered) if it has momentum and energy to pass the surface barrier, which is a simplifying assumption that does not work well e.g. at energies below the surface penetration energy 〔K. O. E. Henriksson, K. Vörtler, S. Dreissigacker, K. Nordlund, and J. Keinonen. Sticking of atomic hydrogen on the tungsten (001) surface. Surf. Sci., 600:3167--3174, 2006〕 or if chemical effects are present.〔C. Hopf, A. von Keudell, and W. Jacob. Chemical sputtering of hydrocarbon films.J. Appl. Phys., 94(4):2373, 2003〕 * The system is layered, i.e. simulation of materials with composition differences in 2D or 3D is not possible. * The threshold displacement energy is a step function for each element, even though in reality it is crystal-direction dependent 〔P. Vajda. Anisotropy of electron radiation damage in metal crystals. Rev. Mod. Phys., 49:481, 1977.〕 SRIM originated in 1980 as a DOS based program then called TRIM.〔 The DOS version was upgraded until 1998 and is still available for download. It will run on a Unix PC having a DOS emulator. SRIM-2000 requires a computer with any Windows operating system. The program may work with Unix or Macintosh based systems through Wine.〔(SRIM plus Linux over Wine (SRIM+(LINUX/WINE)) )〕〔(SRIM Wine Page @WineHQ )〕 ==Further reading== * * * * * 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Stopping and Range of Ions in Matter」の詳細全文を読む スポンサード リンク
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