A new X-ray diffraction-fluorescence method for the study of films: preliminary results for Cu_xS on CdS

The structure of an ion-exchanged layer of Cu_xS on CdS has been studied by an X-ray method which yields diffraction and fluorescence results simultaneously. The method utilized a solid-state Ge crystal detector and a low incidence angle for the X-ray beam. From the fluorescence yield one can estimate the expected diffraction contribution of the surface film. The diffraction results indicated the presence of both chalcocite (Cu₂S) and djurleite (Cu_1.96S). A reversible phase transition near 100°C was observed.