本文用解析的方法研究了应变P型Si_(1-x)Gex层中载流子冻析现象．研究发现，用Si归一化的Si(1-x)Gex价带有效态密度，随x的增加而减小，而且温度T越低，随Ge组份x的增加而减少的速度越快与Si相比，常温下Ge组份x几乎对电离杂质浓度没有什么影响，而在低温下，随Ge组份x的增加，电离杂质浓度随之增加，载流子冻析减弱，这对低温工作的Si(1-x)Gex器件有利． In this paper, the phenomenon of carrier freezing in strained p-type Si_ (1-x) Gex layers has been investigated by analytical method. The results show that the effective density of Si (1-x) Gex valences normalized with Si decreases with the increase of x, and the lower the temperature T, the faster decreases with the increase of Ge x Si at room temperature Ge composition x almost no effect on ionized impurity concentration, and at low temperature, with the Ge component x increases, ionized impurity concentration increases, the carrier cryogenic reduction, which low-temperature work Si (1-x) Gex devices.