CdTe Solar Cell by sputtering method
Lakshmi K. Ganta, Surya Rajendran, Tara Dhakal
Cadmium Telluride (CdTe) solar cells have been of research and commercial interest for many years. CdTe is the second most used material next to silicon in solar cells. It has been known to clock record efficiencies close to 16.5%. Our work is focused on improving the efficiency by adopting a few economical techniques. Closed Space Sublimation (CSS) has been the predominant way of depositing CdTe thin films. We adapted sputtering method and treated the thin film with Cadmium Chloride (CdCl2) and Methanol solution and annealed in oxygen to increase the grain size and later treated it with an acid solution to expose the Tellurium rich layer. All the post processing resulted in a perfect p-type layer which was later used to fabricate a thin film solar cell using Cadmium sulfide (CdS) as n-type layer. The Cell showed promising efficiency of 4.22% for a research cell. Further work is planned to increase the efficiency.