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利用基于Stillinger--Weber(SW)势函数的分子动力学方法分析了Si中30^o部分位错和单空位(V₁)的相互作用. 不同温度、剪应力作用下的计算结果表明, 在
温度恒定条件下, 剪应力较小时, V₁对位错有钉扎作用; 当施加的剪应力达到临界剪应力时, 位错脱离V₁的钉扎继续运动, 并且将V₁遗留在晶体中; 随温度的
升高, 临界剪应力近似线性下降. 通过不含V₁和含有V₁的模型中位错芯位置的对比后发现, V₁对滑过它的30^o部分位错有明显的加速作用.

Dislocation and monovacancy (V₁) are the fundamental defects in Si. The interaction between them is concerned with the electronic and optical properties of electronic devices. In this paper, the interactions of 30^o partial dislocation with V₁ in Si were investigated by the molecular dynamics simulation method based on the Stillinger–Weber (SW) potential. The simulations were conducted under different temperature and shear stress conditions. The results show that 30^o partial dislocation is pinned when dislocation encounters the V₁ under the conditions that shear stress is relatively low and the temperature is kept constant. When the shear stress increases to a critical value, the dislocation can overcome the pin and the V₁ is left in the crystal. As the temperature increases, the critical shear stress decreases approximately as a linear function. Moreover, the values of the critical shear stress corresponding to different dislocation kinks also show that the abilites of kinks to overcome the pin are determinded by the migration barriers of kinks. In comparison of the locations of dislocation core in two models with and without V₁, it is found that the V₁ can make the 30^o partial dislocation move faster once the dislocation glides away from the V_{1 .}