Double-side textured liquid phase crystallized silicon thin-film solar cells on imprinted glass

Abstract

Emerging liquid phase crystallization (LPC) techniques recently rendered a possible substantial progress in the fabrication of high quality crystalline silicon thin-film solar cells on glass. The implementation of an efficient light trapping texture into such LPC silicon devices is still challenging as an excellent bulk material quality and well-passivated interfaces have to be guaranteed. In this paper we present recent advances in light management for LPC silicon thin-film solar cells on imprinted glasses. A double-sided 2µm periodic texture is realized by sandwiching the silicon film during the electron-beam induced crystallization process between an imprinted glass substrate coated with silicon oxide and a silicon oxide capping layer. Amorphous-crystalline silicon (a-Si:H/c-Si) heterojunction solar cells with single sided contacting scheme are fabricated. Textured prototype devices and simultaneously processed planar solar cells exhibit a comparable electronic material quality featuring open circuit voltages above 550mV and efficiencies up to 8.1%. Optical absorption properties of 10µm thick double-side textured silicon films even predict maximum achievable short circuit current densities in solar cells up to 38mA/cm2 assuming zero parasitic absorption.