Structural reproducibility of CdTe thin films deposited on different substrates by close space sublimation method



We report on the characterization of polycrystalline CdTe thin films grown directly on glass, SnO2-coated glass, and CdS/SnO2/glass at relatively low temperatures by employing the close space sublimation technique (CSS). The deposited films have been characterized by using optical absorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX). Based on the SEM and optical analysis, the CdTe/CdS/SnO2/glass thin films exhibit a superior crystal quality and reproducibility in comparison to other CdTe films grown on glass and SnO2/glass. XRD study reveals that films are polycrystalline with a cubic crystal structure. The EDX characterization indicates that all CdTe thin films are nearly stoichiometric. The optical absorption study shows a larger variation of band gap from 1.485 to 1.495 eV for CdTe grown on SnO2-coated glass.