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用气态源分子束外延（ＧＳＭＢＥ）法研究了ＧｅｘＳｉ１－ｘ合金的低温（≤５００℃）生长动力学问题，所使用的源分别是乙硅烷和固态锗．在恒定的乙硅烷流量（４ｓｃｍ）Ｇｅ源炉温度（１２００℃）下，合金中的Ｇｅ组分ｘ随衬底温度的降低而升高；另一方面，当衬底温度（５００℃）和乙硅烷流量（４ｓｃｍ）保持恒定时，合金中的Ｇｅ组分ｘ最初随Ｇｅ源炉温度的升高而增大，当Ｇｅ源炉温度升高到一定值以上时，ｘ值不再随Ｇｅ源炉温度的升高而增大，而趋向于饱和在０．４５附近．基于乙硅烷及Ｈ原子在Ｓｉ原子和Ｇｅ原子表面上不同的吸附和脱附过程，我们定性地解释了上述生长动力学现象
The kinetics of low temperature (≤500 ℃) growth kinetics of GexSi1-x alloy was studied by gaseous source molecular beam epitaxy (GSMBE). The sources used were disilane and solid germanium. The Ge composition x in the alloy increases with the decrease of the substrate temperature at a constant source temperature of the disilane (4scm) Ge source (1200 ℃). On the other hand, when the substrate temperatures (500 ℃) and B When the silane flow rate (4scm) remains constant, the Ge composition x in the alloy initially increases with increasing temperature of the Ge source furnace. When the temperature of the Ge source furnace rises above a certain value, the value of x no longer varies with the temperature of the Ge source furnace The temperature increases and tends to saturate around 0.45. Based on the different adsorption and desorption processes of disilane and H atoms on the Si atom and Ge atom surfaces, we qualitatively explain the above phenomenon of growth kinetics