In-situ detection of interface defects in a-Si:H/c-Si heterojunction during plasma processing

Abstract

Defects in hydrogenated amorphous silicon (a-Si:H)/crystalline silicon (c-Si) heterojunction have been detected via in situ photocurrent measurement during growth of a-Si:H and consecutive postannealing. During growth, defects are generated not only in the a-Si:H layer but also in c-Si. The defects in the a-Si:H layer are completely recovered by postannealing, whereas those in c-Si are partially recovered; the residual defects are formed in c-Si. Interestingly, the postannealing induces the formation of the interface defects at a-Si:H/c-Si, which may deteriorate the performances of a-Si:H/c-Si heterojunction solar cells.