Optimization of the performance of micromorph tandem solar cell a-Si/uc-Si

We have performed a Computer modeling using AMPS 1D and AFORS-HET for optimizing tandem cells on p-i-n/p-i-n configuration. We investigated the influence of the substrate temperature for doped layer deposition technique in the top cell performances and the influence of the thickness of the bottom cell in the density of current that present a crucial parameter in the current matching between subcells. The simulation results demonstrate in one hand that a top cell a-Si with doped layers deposited by PECVD with 1000C substrate temperature provides a notable increase in the efficiency, and in the other hand a bottom cell with 900nm thick intrinsic layer exhibit more density of current. The performances of micromorph cell obtained from simulation give a good agreement with experimental results and confirm the importance of the combination as a double junction solar cell