晶体表面偏角对摇摆曲线及其半峰宽的影响

本文应用X射线衍射动力学理论,计算了晶体表面偏角对X射线双晶衍射摇摆曲线及其半峰宽的影响,得出当晶体表面向某一方向存在一定的偏角时,X射线的入射方向不同,将造成摇摆曲线位置的改变和半峰宽的变化,且其变化趋势随着入射角的变小而增大,随着入射角的减小,反射峰的半峰宽增大,并向高角方向漂移,采用掠入射的不对称衍射方式时,偏角的影响更为明显。 关键词：

THE INFLUENCE OF THE DEVIATION ANGLE ON THE ROCKING CURVE AND ITS WIDETH

The influence of the deviation angle of the sample surface from the exact crystalline surface on the X-ray double crystal rocking curves an{d its full width at half maximum (FWHM) were investigated based on the X-ray dynamical diffraction theory. The results show that when the sample surface has a deviation from the exact crystalline surface, the profile of rocking curves and their FWHMs are dependent on the incident angle and the direction of X-ray beam. Moreover, with the decreasing of the incident angle, the FWHM of rocking curve increases, and the reflection peaks shift to the high angle region. This influence becomes more significant when the asymmetrical diffraction is used.