Electrodeposition of CdTe films on CdS layers deposited using magnetron sputtering and chemical bath deposition

This paper compares the structural and optical properties of electrodeposited Cadmium Telluride films grown on Cadmium Sulphide films prepared by two different methods: pulsed DC Magnetron Sputtering and Chemical Bath deposition (CBD). The films were characterised using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDS) and Spectrophotometry. The SEM and TEM characterisation revealed that the microstructure of the CdTe film was influenced by the deposition method used for the underlying thin film CdS. The CdTe films deposited on the CBD CdS films showed development of bigger crystallites compared to the films grown on the sputtered CdS layer. Thickness measurements showed that the substrate had significant influence on the growth rate of the CdTe, with the material grown on sputtered CdS having 3 times higher deposition rate. Transmission measurements showed that the material deposited on the sputtered CdS had a narrower band gap, 1.41eV, compared to that deposited on CBD CdS, 1.46eV.