Optimization of GaAs 1-x Px/Si Tandem Dual-Junction Solar Cells

In order to attest the feasibility and the concept of great-quality III – V devices, we focus our actual work on the developming of a tandem dual-junction solar cell, including a GaAS1−xPx top cell and a Si bottom cell. A simulation study of the top cell was performed. The impact of GaAS1−xPx absorber layer thicknesses, the temperature, and P composition x on cell efficiency are evidenced. In these structures, a tunnel junction was needed to interconnecting both the bottom and top cell. We comparing the simulated performance of two tunnel junction structure and we will show that the use of the GaAs (n+)/GaAs (p+) tunnel junction improve the performance of the currentvoltage characteristics. An optimal efficiency of about 16.27% was obtained with a thickness of about 1–m, P fraction x=0.37 and a temperature of 285 K.