Investigations on the Physical Properties of CdCl2 Heat-Treated ITO/CDTE/CDS Thin Films Solar Cell

: CdTe/CdS/ITO/glass solar cell was prepared by closed space sublimation (CSS) and chemical bath deposition (CBD). Indium tin oxide (ITO) and tellurium (Te) films were analyzed by spectrophotometry and scanning electron microscopy (SEM). CdTe and CdS thin films were submitted to a chemical treatment at 25°C in a saturated CdCl solution (1.04 g/100 mL methanol), followed by heat treatment at 400°C for 30 min. It has 2 been demonstrated that solar cell performance can be improved by depositing a heat-treated CdCl layer on the 2 CdTe and CdS layers. The optical, structural and morphological changes of CdTe and CdS surfaces in CdTe/CdS/ITO/glass solar cell, due to CdCl solution treatment followed by annealing in air for 400°C were 2 studied using spectrophotometry, XRD and SEM. Optical analysis showed changes in transmittance, refractive index and decrease in thickness and energy band gap after CdCl heat-treatment. XRD and SEM results of CdCl 2 2 heat-treated CdTe and CdS thin film samples showed an overall improved crystal structure with progressive increase in crystallite and grain size.