Numerical Simulations of CdTe Solar Cells Using SCAPS-1D

Cadmium Telluride (CdTe) is one of the promising candidates for thin film solar energy conversion with 23.1% record efficiency. We used numerical simulations to show pathways to achieve conversion efficiencies over 25% by varying the band gap and acceptor densities of the absorber. The minority carrier diffusion equation was referenced for continuity, and reinforced by the results of the bulk simulations in selenium alloyed cadmium telluride. As the band gap was changed due to selenium incorporation, increase in both the Open Circuit Voltage and Fill Factor contributed significantly to increase the overall efficiency of the device. The density of acceptors in the alloy is varied and confirmed to increase the efficiency of the solar cell configuration, thus confirming it as an effective optimization parameter for p-type graded layer.