A model of interdiffusion occurring during the formation of thin metal films on single-crystal silicon under conditions of limited solubility of the components
Abstract
Thin metal films are used in semiconductor and microelectronic devices to form ohmic and non-ohmic contacts to singlecrystal silicon. A common feature of the used Ме–Si systems is the low mutual solubility of elements and the polycrystalline nature of metal films. Solid-phase interactions during the deposition of metals on single-crystal silicon and the subsequent vacuum annealing results in the redistribution of the elements near the Me/Si interface. An important task facing the material science of solid-state electronics is to develop a mechanism of solid-phase interaction of metal thin films and single-crystal silicon. The aim of our study – was to develop a quantitative model of interdiffusion in the Ме–Si system under conditions of limited solubility of the components.
The article suggests a mechanism of formation of Me–Si systems based on the diffusion and segregation of silicon near the intergrain boundaries of the metal and the limited formation of complexes during the diffusion-induced penetration of metal into silicon. The article suggests a model of reactive interdiffusion in thin metal film – single-crystal silicon systems under conditions of limited solubility of the components. Mathematical modelling was used to study the interaction of magnetron-sputtered metals Ti, W, and Nb with single-crystal silicon during isothermal vacuum annealing. The numerical analysis of experimental distributions of concentrations of Me and Si obtained by Rutherford backscattering spectroscopy allowed us to determine their individual diffusion coefficients in Me-Si systems.
The model can be used for empirical studies of the redistribution of the elements of two-layer systems with limited solubility, as well as to forecast the technological conditions for the production of electronic devices.
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References
Murarka S. P. Silicides for VLSI applications. Elsevier Science; 1983. 200 p.
Thin Films: Interdiffusion and Reactions (Eds: J. M. Poate, K. N. Tu and J. W. Mayer). New York: Wiley; 1978. 578 p.
Smigelskas A. D., Kirkendall E. O. Zinc diffusion in alpha-brass. Transactions of the American Institute of Mining and Metallurgical Engineers. 1947;171:130–142.
Adamchuk V. K., Lyubinetsky I. V., Shikin A. M. Peculiarities of silicon interaction with noble- metals. Soviet Technical Physics Letters 1986;12(17): 1056–1060. Available at: https://www.elibrary.ru/item.asp?id=42823964
Prasad S., Paul A. Growth mechanism of phases by interdiffusion and diffusion of species in the niobium–silicon system. Acta Materialia. 2011;59: 1577–1585. https://doi.org/10.1016/j.actamat.2010.11.022
Darken L. S., Diffusion, mobility and their interrelation through free energy in binary metallic systems. Transactions of the American Institute of Mining and Metallurgical Engineers. 1948;175: 184–201. https://doi.org/10.1007/s11661-010-0177-7.
Gurov K. P., Kartashkin B. A., Ugaste Yu. E. Mutual diffusion in multiphase metallic systems. (Ed. K. P. Gurov. Moscow: Nauka Publ.; 1981. 352 p. (In Russ.)
Barge T., Gas P. d’Heurle F.M. Analysis of the diffusion controlled growth of cobalt silicides in bulk and thin film couples. Journal of Materials Research. 1995;10: 1134–1145. https://doi.org/10.1557/JMR.1995.1134
Milanesea C., Buscagliab V., Magliaa F., Anselmi-Tamburinia U. Reactive growth of niobium silicides in bulk diffusion couples. Acta Materialia. 2003;51(16): 4837–4846 https://doi.org/10.1016/S1359-6454(03)00323-9
Gas P., D’Heurle F. Diffusion processes in silicides: A comparison between bulk and thin film phase formation. MRS Online Proceedings Library. 1995;402: 39–50. https://doi.org/10.1557/PROC-402-39
Aleksandrov O. V., Kozlovski V. V. Simulation of interaction between nickel and silicon carbide during the formation of ohmic contacts. Semiconductors. 2009;43: 885–891 (). https://doi.org/10.1134/S1063782609070100
Afonin N. N., Logacheva V. A. Modeling of the reaction interdiffusion in the polycrystalline systems with limited component solubility. Industrial laboratory. Diagnostics of materials. 2019;85(9):35-41. (In Russ.) https://doi.org/10.26896/1028-6861-2019-85-9-35-41
Afonin N. N., Logacheva V. A. Interdiffusion and phase formation in the Fe–TiO2 thin-film system. Semiconductors. 2017;51: 1300–1305. https://doi.org/10.1134/S1063782617100025
Afonin N. N., Logacheva V. A. Cobalt modification of thin rutile films magnetron-sputtered in vacuum. Technical Physics. 2018;63: 605–611). https://doi.org/10.1134/S1063784218040023
Afonin N. N., Logachova V. A. Modeling of interdiffusion and phase formation in the thin-films two-layer system of polycrystalline oxides titanium and cobalt. Kondensirovannye Sredy i Mezhfaznye Granitsy = Condensed Matter and Interphases. 2019;21(3): 358–365. https://doi.org/10.17308/kcmf.2019.21/1157
Afonin N. N., Logachova V. A. Reactive interdiffusion of components in a non-stoichiometric two‑layer system of polycrystalline titanium and cobalt oxides. Kondensirovannye Sredy i Mezhfaznye Granitsy = Condensed Matter and Interphases. 2020;22(4): 430–437. https://doi.org/10.17308/kcmf.2020.22/3058
Samarskii A. A., Theory of difference schemes. Moscow: Nauka Publ.; 1977. 656 p. (In Russ.)
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