Depth profile analysis of poly-crystalline layers structure and crystal grain size under surface using x-ray diffraction at small glancing angles of incidence

Abstract

The peak profiles of the diffracted x-ray intensity were investigated as function of incidence angles at small glancing angle incidence of x-rays on a poly-crystalline surface. The intensity of x-ray propagation in surface layer materials characterized by a complex refractive index that changes continuously with depth was derived, and with use of the result, an analyzing method for evaluating the structure of the poly-crystalline layers and the distribution of crystal grain size in the surface layers was studied. The dependence of the diffracted x-ray intensities on the glancing angle lead to the depth profile of the poly-crystalline layers of oxidized iron with accuracy of the order of nanometers. The incidence angle dependence of the peak width of diffracted x-rays lead to the depth profile of the crystal grain size of iron in the surface layer. The evaluated result is very small. It shows the crystallites size in the crystal grain under mechanically polished iron surface. Now, the analysing method for the depth profile of poly-crystalline surface using x-ray diffraction at small glancing angles of incidence was discussed with correction on some errata of equations in the previous studies.