Thin base-layer single crystal silicon solar cells with ECR plasma CVD grown emitters

摘要

Thin (similar to 16 mum.) base-layer monocrystalline silicon solar cells have been investigated with microcrystalline or epitaxial n-type emitters grown at low temperatures (<550 C) by electron cyclotron resonance (ECR) plasma-enhanced chemical vapour deposition (PECVD). The p-type, 1-2 Omega cm, base layers were epitaxially deposited by conventional thermal CVD onto monocrystalline Si p(+) substrates. An efficiency of 13.72% was achieved in the best epitaxial emitter cell after ECR hydrogen passivation and the application of a SiNx anti-reflection coating deposited by ECR PECVD. Cells with microcrystalline Si emitters processed in a similar fashion gave a maximum efficiency of 10.73%. The cell performance was analysed using the two-diode model and the solar cell modelling programme PC-1D. The results are presented. It was necessary to invoke a three-layer PC-1D model to obtain self-consistent fits to the light and dark I-V characteristics and spectral response data. [References: 24]