Efficiency Enhancement Using an Extra BSF Layer in Single-Layer GaAs Solar Cell

This work aims to report a simulation study to enhance the performance of single layer GaAs solar cells using an extra BSF layer via SILVACO TCAD. The efficiency of a single layer GaAs solar cell with one BSF layer is enhanced by optimizing the doping and thickness for the cell layers. Then, the efficiency is improved further by introducing a second BSF layer of nGaAs. The results show an increment in conversion efficiency for the solar cell from 21.88% to 23.6% as the doping and thickness are optimized compared to the initial cell. Moreover, as a second BSF layer of an optimum thickness of 0.08 µm is introduced, the conversion efficiency reaches 25.55%. This enhancement in the cell performance after implementing the second BSF layer is correlated to the electric field created at the junction between the base and the upper BSF layer, which reduces the recombination rate and enhances the cell photocurrent.