Comparison of Cadmium Selenide Thin Films deposited by chemical bath and pulsed DC sputtering for use in Cadmium Telluride devices

Cadmium selenide (CdSe) thin films deposited using chemical bath deposition and pulsed DC magnetron sputtering are compared for use in cadmium telluride/selenide (CST) photovoltaic (PV) devices. Full devices were made from the bath and sputtered films using a cadmium chloride (CdCl2) treatment temperature of 425°C, this gave an overall efficiency of 9.3% and 3.2% respectively. Photoluminescence (PL) of the sputtered sample confirmed a bandgap was present of 1.58 eV which suggested poor diffusion at 425°C. A (CdCl2) treatment temperature of 465°C gave a large PL peak at 1.37 eV which corresponds to the bandgap of CST, indicating diffusion was more effective at this temperature.