Effect of Thermal and Chemical Treatment on Electrodeposited CdTe Thin Films for Solar Cell Applications

摘要

Electrodeposition of nanocrystalline CdTe thin films from an acidic sulfate aqueous electrolyte wasperformed using different potential values to study the effect of the electrodeposition potential andthermal and chemical treatments on the structure, morphology and optical properties of the resultingfilms. Electrodeposition at -0.62 V(SCE) followed by heat and CdCl2 treatment was used to produceCdTe films that showed a highly crystalline cubic structure, did not exhibit any free Te, had definedgrains and free cracks and were nearly stoichiometric with a band gap of 1.44 eV. The properties ofCdTe films were studied using X-ray diffraction (XRD), Raman spectroscopy, scanning electronmicroscopy (SEM), energy dispersive X-ray, and UV-Vis spectroscopy. The J characteristic curve2 of the CdTe/CdS solar cell was investigated under illumination intensity of 100 mW/cm . Voc of 0.732 V, Jsc of 20 mA/cm , FF of 50%, and of 9% were measured for the solar cell based on CdTe film thatwas electrodeposited at -0.62 V(SCE) and then treated by heat and CdCl2.