摘要
利用连续介质模型，计算有非应变盖层的应变外延层结构中单位面积的能量．引入上下界面失配位错数目的比例因子η，利用能量最低原理，求得η的表达式．研究表明，失配位错在上下界面的分布与应变的弛豫程度和盖层的厚度有关．随应变弛豫程度和非应变盖层厚度的增加，失配位错在上界面的数目增多。
In this paper, the total energy in the strained layer with nonstrained capping layer is calculated using continuum model. The ratio of the densities of the misfit dislocations at the upper and lower interfaces, η , is included. We found that for a given partially relaxed strained layer, there is a minimum energy, which corresponds to a certain value of η . The expression of η is derived using the minimum energy principle. The distributions of misfit dislocations at the upper and lower interfaces are related to the strain relaxation and the capping layer thickness. The number of the misfit disloccations increases with an increse in the strain relaxation, and the single kink mechanism changes into the double kink one. With an increase in the capping layer thickness, the samilar change occurs. This perfects the theory of misfit dislocation nucleation and propagation.
出处
《吉林大学自然科学学报》
CAS
CSCD
1999年第1期67-70,共4页
Acta Scientiarum Naturalium Universitatis Jilinensis
基金
国家自然科学基金
自然科学基金
关键词
失配位错
非应变盖层
应变外延层结构
半导体
distribution of misfit dislocation, nonstrained capping layer, the ratio of the densities of the misfit dislocations at the upper and lower interfaces
