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本文利用Ｗｅｎｚｌ的ＧａＡｓ缺陷模型研究了在Ｔ＝１１５０℃时，Ｇａ１－ｘＡｓｘ固溶体化学计量比偏离度（Ｓ＝１－２ｘ）对ＧａＡｓ晶体气固相平衡的影响．计算表明平衡Ａｓ压在晶体富Ａｓ情况下（即Ｓ＜０）随Ｓ的减小，迅速增加、而在富Ｇａ情况下（即Ｓ＞０）随Ｓ的增大趋于零．为了了解杂质对相平衡的影响，本文考虑了非掺ＬＥＣ晶体中两种浓度较高的杂质Ｃ和Ｂ，发现在Ｃ浓度为１．５４×１０１６ｃｍ－３时，平衡Ａｓ压的变化趋势基本不变，Ａｓ压只有少许增加．在Ｂ浓度为２．２×１０１７ｃｍ－３时，平衡Ａｓ压在富Ａｓ侧有较大降低．
In this paper, we use Wenzl’s GaAs defect model to study the influence of Ga 1-x Asx solid solution stoichiometry bias (S = 1-2x) on the gas-solid equilibrium of GaAs crystals at T = 1150 ℃. Calculations show that the equilibrium As pressure increases rapidly with the decrease of S in the case of crystal-rich As (ie S <0), whereas increases with S in the case of rich Ga (ie, S> 0) tends to zero. In order to understand the effects of impurities on phase equilibrium, we consider two kinds of impurities C and B with higher concentration in non-doped LEC crystals. It is found that the trend of equilibrium As pressure is basically not at C concentration 1.54 × 1016cm-3 Change, As pressure only a little increase. When the concentration of B is 2.2 × 10 17 cm-3, the equilibrium As pressure is greatly reduced on the As-rich side.