Reducing light reflection by processing the surface of silicon solar cells

Abstract

This study discussed a surface processing technique for improving the energy conversion rate of solar cells with silicon as the substrate. The technique involves texturing the surface of a silicon substrate and coating it with an antireflective layer to enhance its antireflective property and thereby its photoelectric conversion efficiency. Double surface texturing (DST) texture was formed through photolithography and anisotropic wet etching, and radio frequency magnetron sputtering was performed to deposit the SiO2/TiO2 double-layer antireflective coating to reinforce the surface texture of a silicon solar cell. Subsequently, a scanning electron microscope was employed to analyze the DST texture before and after the surface was coated with a double-layer antireflective coating (ARC). An UV–VIS spectrophotometer attached with an integrating sphere was then applied to measure the light absorption rate of the processed surface at different wavelengths. After optimum DST and double-layer ARC treatments, the average reflectance within the visible light reduce to 9.94%, which means the absorption of incident light into the absorption layer was enhanced to improve the energy conversion efficiency of silicon solar cells.