An Efficient Light Trapping Method to Enhance the Efficiency of Thin Film Solar Cell

Abstract

An efficient light management technique is proposed and investigated by developing a TCAD model for microcrystalline silicon based thin film solar cell. The model includes physical insight related to some optical phenomenon like scattering and diffusive reflection of light as well as some electrical phenomena like carrier transport at the heterointerfaces. Two different structures, which comprises of sawtooth and grating-type back nanotextured in combination with random front nano-textured absorber layers are considered in this work. It has been observed that sawtooth or grating type back nano-textured absorber layer results in enhanced absorption of incident photons as compared to the planar back absorber layer. Also, the grating type back-textured absorber provides better performance compared to its sawtooth counterparts. Finally, the depth and period of grating are optimized in order to maximize the power conversion efficiency of grating-back-textured with random-front-textured absorber. The optimized structure results in an efficiency of 12.325% which corresponds to an improvement of 3.975% compared to the random front and back nano-textured thin film solar cell.