Electrical properties of N-type CdS and P-type CdTe thin films in CdS/CdTe solar cells

Cadmium Sulfide thin films have been deposited on cleaned glass substrates in vacuum at various deposition conditions. The Cadmium Telluride powder was coated on copper foil by three methods respectively. Then, the samples were sintered at high temperature in a furnace. The effects of the deposition conditions on the thin film properties were investigated by measuring electrical resistivity and conduction type. By investigating the electrical properties of the thin films, we find that the thin film transparency strongly depends on the Cadmium dopant concentration rather than the thickness. On the other hand, the CdTe/Cu sintered film shows a strong p-type property and has an extremely small resistivity. Pinholes and cracks of the thin films were also discussed.