2D Modeling and optimization of excimer laser annealed thin film polysilicon solar cells

In this work, we propose a low-cost, reliable polysilicon solar cell structure suitable for excimer laser annealing (ELA) process and present an optimization method to maximize the cell efficiency by addressing the tradeoffs between the doping profile, the device width, and the trap density (Nt) within the grain boundaries (GBs) of the proposed structure. We also investigate the variation in cell performance with respect to the number and position of the GBs within the device to obtain a better understanding of performance variations. The optimized cell also demonstrates the possibility of having thin film transistors (TFTs) and solar cells on the same substrate, leading to new applications such as self-powered, low-cost, wireless sensor nodes.

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