Property Investigation of a-Si/c-Si Hetero-Junction Structure

Abstract

Abstract:This paper investigated the influence of a-Si/c-Si band offset, amorphous silicon emitter doping concentration and interface defects density on interface property of a-Si/c-Si structure. Band offset in a-Si(N+)/c-Si(P) hetero-junction and a-Si emitter high level doping is very useful for the transformation of recombination mechanism from dangling bond to SRH(Shockly-Read-Hall). AFORS-HET simulation indicates that a-Si(N+) emitter doping level of over 1.5×1020 cm-3 on c-Si(P) is an indispensable condition for achieving high efficiency. Comparing with density of short circuit current, open circuit voltage of a-Si/c-Si structure cell is much more susceptible to interface defect density.

Key words:amorphous silicon/crystal silicon,emitter doping,interface defect density(Dit)

CLC Number:

TM914.4

WANG Jian-Qiang-1, 2 , GAO Hua-2, ZHANG Jian-2, ZHANG Song-1, LI Chen-1, YE Qing-Hao-1, MENG Fan-Ying-1. Property Investigation of a-Si/c-Si Hetero-Junction Structure[J]. Journal of Shanghai Jiaotong University, 2011, 45(06): 798-803.

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