Roles of hydrogen atoms in p-type Poly-Si/SiOx passivation layer for crystalline silicon solar cell applications

摘要

Cyclic dehydrogenation-rehydrogenation experiments have been performed on p-type poly-Si/SiOx stack to study the roles of hydrogen (H) atoms for crystalline silicon (c-Si) surface passivation. The effective lifetime of minority carriers is enhanced to 1.4 ms by the hydrogenation of hydrogen plasma treatment (HPT) at 300 degrees C. The dehydrogenation by thermal annealing at 450 degrees C decreases the lifetime to similar to 0.6 ms, which is recovered by a consecutive HPT, underlining the c-Si surface passivation by H atoms diffused into the SiOx/c-Si interface. The lifetime recovery follows a stretched exponential function, indicating the dispersive nature of the p-type poly-Si/SiOx stack. (C) 2019 The Japan Society of Applied Physics