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对ＭＢＥ生长的ＧｅｘＳｉ１－ｘ合金膜用Ｒａｍａｎ光谱分析了其中的组分和应力，发现较厚的ＧｅＳｉ膜应变较小，说明随着膜厚的增加，合金膜内原子排列发生了弛豫。２０ｎｍ厚的Ｇｅ０．４Ｓｉ０．６样品经过ＲＨＴ处理（１０００℃、１０ｓ），应变减小为原始膜的１／４～１／５。说明退火后膜几乎被完全弛豫，同时引入大量的穿通位错缺陷。用退火前后２０ｎｍ样品制作了ＧｅＳｉ／Ｓｉ异质结内光发射红外探测器件。在７７Ｋ下测量，退火前样品的异质结反向电阻达５００ｋΩ以上，而退火后样品只有１ｋΩ左右，根本无法在７７Ｋ下工作。我们提出的方法可以同时确定膜的Ｇｅ组分及膜内应力，方法是非破坏性的。
The composition and stress of the GexSi1-x alloy grown on MBE were analyzed by Raman spectroscopy. It was found that the thicker GeSi film had smaller strain, indicating that the atomic arrangement of the alloy film relaxed with the increase of film thickness. The 20nm-thick Ge0.4Si0.6 samples were RHT treated (1000 ℃, 10s) and the strain was reduced to 1/4 ~ 1/5 of the original film. Indicating that the film is almost completely relaxed after annealing, while introducing a large number of threading dislocation defects. GeSi / Si heterojunction internal light-emitting infrared detector was fabricated by using 20nm samples before and after annealing. Measured at 77K, the sample before annealing heterojunction reverse resistance of more than 500kΩ, while the sample after annealing only 1kΩ, simply can not work at 77K. The method we proposed can simultaneously determine the Ge composition of the film and the stress in the film, and the method is non-destructive.