Influence of substrate texture on microstructure and photovoltaic performances of thin film polycrystalline silicon solar cells

Abstract

Thin film polycrystalline silicon (poly-Si) solar cells have been fabricated by plasma enhanced chemical vapor deposition on differently textured ZnO/Ag/SnO 2/glass substrates. Using a textured substrate with the root mean square (RMS) roughness ( σ) of 38 nm, the conversion efficiency of 8.22% has been achieved due to improvement of long wavelength responses. Whereas using textured substrates with σ>38 nm , (2 2 0) preferential growth is deteriorated, yielding decreases in both short circuit current and open circuit voltage. The field-dependent carrier collection behaviors reveal that the carrier diffusion length in the poly-Si layer on textured substrates with σ>38 nm decreases due to the change in poly-Si microstructure.