研究半导体超晶格界面粗糙的X射线双晶Pendellosung方法

INVESTIGATION OF PENDELLOSUNG FRINGE ON SUPPERLATTICE INTERFACE ROUGHNESS BY DOUBLE CRYSTAL X-RAY DIFFRACTION

运用高精度X射线双晶衍射议对GeSi/Si应变超晶格进行了分析研究,实验上观测到在卫星峰之间存在着干涉条纹(Pendellosung),建立了界面的随机概率模型.结合计算机模拟发现:Pendellosung条纹对界面的粗糙十分敏感,当界面粗糙度较小时,只影响Penderllosung条纹的规则排列,而当粗糙度较大时,不仅使Pendellosung条纹强度下降,规则排列受到破坏,并且还将导致高级卫星峰强度下降,峰形严重宽化.

We investigate the interface roughness of GeSi/Si superlattice by high resolution X-ray diffractmeter. In our experiment, interference fringes between satellite peaks were found. A mathematical model of interface roughness was proposed. By means of this model, we calculate the diffraction profile, which is in a good agreement with the experiment. Interface roughness not only affects the regular arrang-ment of the pendellosung fringes, but also makes the intensity of satellite peak descend and the width of satellite peak enlarged.