Ion beam (RBS) and XRF analysis of metal contacts deposited on CdZnTe and CdTe crystals

Rutherford Backscattering Spectrometry (RBS) using 6 MeV alpha particles and X-Ray Fluorescence (XRF) using a Pd-anode X-Ray generator were performed to characterize Au and Pt contacts deposited by electroless technique and thermal evaporation on differently treated surfaces of CdZnTe and CdTe crystals. The aim of this study is to understand and improve the structure of the material-electrode interface. The thickness, the stoichiometry and the concentration profiles of platinum, gold, cadmium, zinc, tellurium and oxygen present at the surface layers were determined. The distribution of Cd deficiency at the interface layers was profiled using simulations and showed complex profiles in the samples, which can greatly affect the electrical quality of the detectors.