基于能量最小近似模型，研究了应变异质结外延材料中，产生Ｆｒａｎｋ－Ｒｅａｄ源以释放失配应力所需ＧｅＳｉ合金缓冲层的厚度．对ＧｅｘＳｉ１－ｘ／Ｓｉ进行了具体计算，其结果表明：产生Ｆｒａｎｋ－Ｒｅａｄ源时缓冲层厚度要比临界厚度大得多，Ｌｍｉｎ＝１３００Ａ是钉扎点间的最小距离．计算结果与ＬｅＧｏｕｅｓ等的实验结果相符．就作者所知，计算产生Ｆｒａｎｋ－Ｒｅａｄ源时ＧｅＳｉ合金缓冲层厚度的工作，以前未见报道． Based on the least-energy approximation model, the thickness of the GeSi alloy buffer layer required to generate the Frank-Read source to release the mismatch stress in the strained heterojunction epitaxial material was studied. The specific calculations for GexSi1-x / Si show that the thickness of the buffer layer is much larger than the critical thickness when the Frank-Read source is generated, and Lmin = 1300A is the minimum distance between pinning points. The calculation results are consistent with the experimental results of LeGoues et al. To the author’s knowledge, the work of calculating the thickness of GeSi alloy buffer layer when generating Frank-Read source has not been reported before.