双势垒超晶格结构的同步辐射及X射线双晶衍射研究

STUDY OF DOUBLE BARRIER SUPERLATTICE BY SYNCHROTRON RADIATION AND DOUBLE CRYSTAL X RAY DIFFRACTION

利用高精度的Ｘ射线双晶衍射和同步辐射散射对可用于半导体红外探测器的双势垒超晶格材料进行了研究，并运用Ｘ射线衍射动力学理论进行模拟计算，得到了与实验结果符合得很好的理论曲线．同时发现包络函数节点处的卫星峰对结构参数的变化极为灵敏．以此进行模拟计算，可准确地确定出样品的结构参数，厚度误差范围为±０１ｎｍ．

A AlAs/GaAs/AlAs/AlGaAs double barrier superlattice grown on GaAs substrate by MBE has been studied by combining double crystal X ray diffraction and synchrotron radiation. This combination provides a comprehensive structural analysis.During simulated by X ray dynamical diffraction theory, we find the intensity of satellite peaks which situated nearby the modulated wave point of one layer are very sensitive to the variation of the layer's structural parameters. Accoding to these, the accurate layer thickness can be get with an error less than 0 1nm. The modulated phenomenon is investigated by X ray kinematical diffraction theory.