Фазовая диаграмма системы Ge-Si

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Ge-Si

Ge-Si (Germanium-Silicon) R.W. Olesinski and G.J. Abbaschian The equilibrium phases of the Ge-Si system are (1) the liquid; and (2) the cubic, diamond-type, substitutional solid solution. The assessed phase diagram is based primarily on the X-ray and thermal data of [39Sto]. Anomalous thermal arrests, at approximately 10 C below the melting point of Ge, were also reported by [39Sto] during normal cooling of various alloys from the molten state, but not during heating. Under high pressure, the Ge-Si solid solution was found to transform to a two- phase mixture at low temperatures (below 300 K). A bct structure of the (Ge,Si) solid solution, at high pressures (above 300 kbar), was found to be more stable than the diamond-type structure at lower pressures [82Som]. Amorphous Ge-Si films, a few micrometers thick, of various compositions have been prepared on fused silica substrates by RF sputtering in an argon atmosphere. The Ge-Si system has also been studied theoretically, using an electronic theory based on pseudopotentials [74Bub, 75Alt]. Phase equilibria based on strictly regular solid and liquid solutions agree well with the measured diagram, with enthalpy of mixing coefficients in the solid and liquid of 6.50 and 3.50 kJ/mol, respectively. 39Sto: H. Stohr and W. Klemm, Z. Anorg. Chem., 241, 305-323 (1939) in German. 74Bub: V.T. Bublik, S.S. Gorelik, A.A. Zaitsev and A.Y. Polyakov, Phys. Status Solidi (b), 65, K79-K84 (1974). 75Alt: A.M. Altshuler, Yu.Kh Vekilov and G.R. Umarov, Phys. Status Solidi (b), 69, 661-671 (1975). 82Som: T. Soma, H. Iwanami, and H. Matsuo, Solid State Commun., 42, 469-471 ( 1982). Published in Bull. Alloy Phase Diagrams, 5(2), Apr 1984. Complete evaluation contains 2 figures, 3 tables, and 27 references. 1