单晶硅(001)衬底材料中非经典衍射的研究

Investigation into the Forbidden Reflection from the Single Crystal (001) Silicon Substrate

在经典衍射理论中 ,不产生Si(2 0 0 )反射 .对此 ,作者通过理论和实验进行了证实 .由于Si晶体中电子云分布的非对称性 ,会出现Si(2 0 0 )衍射峰 .论述了Si(2 0 0 )

In the conventional theory of X ray diffraction, the Si (200) reflection is forbidden. However, by means of Y4Q diffractometer using Cu K α radiation, a very weak forbidden reflection can be seen from a single crystal (001) silicon substrate. It is a fact that the calculated results are good in agreement with observed values, which suggests that the reason for the forbidden 200 reflection may be ascribed mainly to the antisymmetric charge density distribution. The results are discussed, and the emphasis is on the application of Si (200) reflection in X ray analysis.