应变弛豫InGaAs/GaAs超晶格的X射线双晶衍射及形貌研究

应用X射线双晶衍射及双晶形貌术,对应变弛豫的InGaAs/GaAs超晶格作了研究,通过对双晶衍射摇摆曲线的计算机模拟,得到了超晶格的结构,应变弛豫机制,弛豫比,超晶格层与衬底的取向差等重要参数。从双晶形貌,得到了超晶格与衬底界面处和超晶格中的位错分布。 关键词：

X-RAY DOUBLE-CRYSTAL DIFFRACTION AND TOPOGRAPHY STUDY OF STRAIN RELAXED InGaAs/GaAs SUPERLATTICES

In this paper, strain relaxed InGaAs/GaAs strained-layer superlattice has been studied by X-ray double-crystal diffraction and topography. By simulating the double-crystal rocking curves using X-ray dynamical scattering theory, important imformation such as the structure, the mechanism and degree of strain relaxation, the misorientation between the superlattice layers and the substrate and misfit dislocation density, and so forth are obtained. The misfit dislocation distribution at the interface between the superlattice layers and the substrate and in the superlattice layers are observed by double-crystal topography.