Heterojunction silicon solar cells performance optimization and sensitivity reduction to the interface defect states

Two new buffer layers are introduced in structure of the silicon heterojunction solar cell to optimize the performance of the cell. The buffer layers are thin (p+) crystal silicon layer and a thin (n+) crystal silicon layer deposited on both front and back sides of the substrate. By adding the layers, in addition to increasing the solar cell's performance significantly, the sensitivity of the solar cell's output parameters to the interface defect states is reduced. Role of the added layers on the performance of the solar cell is studied by numerical simulations. Both layers are optimized in terms of doping concentration and thickness, and an increase of in efficiency, an increase of 38 in open circuit voltage and a increase in fill factor obtained compared to the baseline cell. The defect presence probability in both silicon layers are also studied. It is concluded that, if the defect density is less than , the solar cell performance does not change considerably.