摘要
本文采用了以解理面为衍射基面，直接测量水平弛豫的方法测量了InxGa1-xAs（衬底为GaAs，x～0．1）外延层的应变及其弛豫状态．在以解理面为衍射基面的衍射曲线上清楚地观测到了衬底峰与外延峰的分裂．表明当InGaAs层厚度较厚（～2μm）时，InGaAs外延层与衬底GaAs已处于非共格生长状态，同时发现大失配的InGaAs晶胞并没有完全弛豫恢复到自由状态．其平行于表面法线的晶格参数略大于垂直方向上的晶格参数（△a／a～10-3）．并且晶胞在弛豫过程中产生了切向应变．在考虑了切向应变的基础上准确地确定出了InGaAs层的In组分x．
We present a direct measurement of lattice relaxation on InGaAs/GaAs by employing diffraction on the cleavage plane. Both the substrate and the epitaxial layer peaks are clearly observed on the X-ray diffraction pattern, which means the InGaAs layer grown incoherently with the GaAs substrate. Shear strain is also occured and the lattice parameter is slight larger along the vertical direction than along the lateral direction(△a～ 103). Futhermore, based on the shear strain model, the composition of in is determined with high resolution.
