Effects of Refraction and Reflection on Analysis of Thin Films by the Grazing-Incidence X-ray Diffraction Method

Abstract

Abstract The grazing-incidence X-ray diffraction (GIXD) method was employed to analyze two-layer thin films, which were the samples of Å lOO Å Au/500Å Cu/Si0 2 (substrate) and 250Å Cu/500Å Au/SiO 2 (substrate), which were prepared by the evaporation technique under the condition that the SiO 2 substrate was at room temperature. Diffraction profiles were obtained at various glancing angles ( α ) and the data were analyzed as a function of α. The results were as follows : 1) Diffraction peaks were shifted to larger diffraction angles, because of the refraction of the incident X-ray beam. The angular shift has been approximated by the equation, α - α 2 - α c 2 ) 1/2 , where α c is the total ref reflection critical angle of the material. 2) As a result of the correction of angular shift, the stress of the evaporated films was estimated to be null. 3) The broadening of the Cu diffraction peak and the enhancement of the Cu diffraction intensity occurred at angles near α c of Cu, due to the reflection of the X-ray beam at the Cu/Au interface.