Theoretical performance of GaAs solar cell, with band gap gradient layer on the back region

GaAs solar cell with graded band gap layer in the back region is analyzed as a function of the electric field created by band gap gradient and the base thickness. Studies are reported at AM 1.5, and unity solar concentration. The optimum thickness of the base region is determined. The performance of the cell strongly depends on the electric field. Comparison with the GaAs cell including high-low junction at the back surface show that the use of back surface field created by graded band gap improve the performance of the GaAs conventional cell.