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结合应变异质界面能带排列的平均键能理论和形变势方法，确定了三种不同衬底上生长的Ｓｉ／Ｇｅ系统在（００１）和（１１０）两种不同晶面上的价带能量不连续值（Ｅ＿ｖ）得出了Ｓｉ／Ｇｅ系统的Ｅ＿ｖ值随其衬底Ｓｉ＿ｌ－ｘＧｅ－ｘ的组分ｘ变化的定量关系结果表明，Ｓｉ／Ｇｅ系统价带平均能量的不连续性（Ｅ＿ｖ，ａｖ）基本不随应变状态的不同而变化，而最高价带的Ｅ＿ｖ值则表现出对弹性应变的高度敏感性（变化量约达０．５ｅＶ），此效应主要来源于单轴应力对价带结构的影响．Ｓｉ／Ｇｅ系统在（００１）面和（１０）面上的Ｅ＿ｖ值略有差别，表现出弱的晶格取向的相关性本文对（００１）面的计算结果与新近的归一保持赝势方法的大型超原胞计算结果以及相关的实验值相当一致．
Based on the theory of average bond energy and deformation potential of the band-aligned strained heterogeneous interface, the valence band energy of (001) and (110) on two different crystal planes of Si / Ge system grown on three different substrates was determined (E_v) The quantitative relationship between the E_v value of Si / Ge system and the composition x of Si_l-xGe-x substrate is obtained. The results show that the average energy discontinuity (E_v , Av) basically does not vary with the strain state, while the E_v value of the highest valence band shows a high sensitivity to elastic strain (about 0.5eV variation), mainly due to uniaxial stress on the valence band structure Impact. The E_v values on the (001) and (10) planes of the Si / Ge system are slightly different and show the dependence of the weak lattice orientation on the (001) plane and the new normalized retention pseudopotential method The results of large supramolecular cells and related experimental values are quite consistent.