Periodic and Random Substrate Textures for Liquid-Phase Crystallized Silicon Thin-Film Solar Cells

Abstract

A major limitation in current liquid-phase crystallized (LPC) silicon thin-film record solar cells is optical losses caused by their planar glass-silicon interface. In this study, silicon is grown on nanoimprinted periodically, as well as randomly textured glass substrates, and successfully implemented into state-of-the-art LPC silicon thin-film solar cells. Compared with an optimized planar reference device, both textures enhance absorption of light. Interlayer and process optimization allowed achieving a material quality comparable with the planar reference device. On the random texture, an open-circuit voltage above 630 mV was obtained, as well as an external quantum efficiency exceeding the planar reference device by +3 mA/cm2.