Effects of surface roughness on aluminum local back surface field silicon wafer solar cells

Abstract

Screen-printed aluminum local back surface field (Al-LBSF) solar cells are a promising candidate for highefficiency industrial silicon-based solar cells. For improving the conversion efficiency, industrial LBSF cell process flows typically comprise rear side planarization to reduce the surface roughness. In this paper, we investigate the influences of rear surface topographies on wet chemical polishing LBSF cells. The best conversion efficiency of 19.09% on screen-printed LBSF cell with polished rear surface was demonstrated.Index Terms -passivation, local back surface field, surface roughness, silicon solar cell, aluminium oxide.