Back Reflectors of Thin-film Silicon Solar Cells Consisting of One-dimensional Diffraction Gratings and One-dimensional Photonic Crystal

Abstract

We designed a type of reflector that consisted of one-dimensional diffraction gratings and one-dimensional photonic crystal.It can be used for thin-film silicon solar cells.The structure parameters were optimized by Legendre polynomial expansion method,and the reflectivity at the range of 400~1 200 nm was calculated.Under the high reflectivity one-dimensional photonic crystal,the propagation path of the photon can be extended and absorbed in the battery.The results show that the diffraction grating and a back reflector in the photonic crystal structure are efficient at the range of 750~1 100 nm.Back-reflection layer can greatly improve the light harvesting capacity and enhance the conversion efficiency of solar cells.