Impact of boron incorporation on properties of silicon solar cells employing p-type polycrystalline silicon grown by aluminum-induced crystallization

摘要

We report on our attempt to increase the carrier density in the p-type polycrystalline silicon (poly-Si) layers grown by aluminum-induced crystallization (AIC) employing a B-doped Si target. Hall measurement revealed that we could obtain a lower-resistance and heavily doped p-type continuous poly-Si thin layer formed by AIC using B-doped a-Si. According to our evaluation of tunnel oxide passivated contact (TOPCon) solar cells with AIC-grown poly-Si, the AIC-TOPCon solar cells fabricated at 570 degrees C using B-doped a-Si showed higher conversion efficiency of 13.5% than that of 12.8% when using nondoped a-Si. It is considered that the cell characteristics, particularly FF and V-oc, were improved owing to the lower series resistance and higher carrier density since both Al and B were successfully incorporated into the AIC-grown poly-Si. (C) 2018 The Japan Society of Applied Physics