Light Reflection Loss Reduction by Nano-Structured Gratings for Highly Efficient Next-Generation GaAs Solar Cells

Abstract

This paper mainly focuses on increasing the conversion efficiency of GaAs solar cells by reducing the light reflection losses. The design of nano-structured gratings and their light trapping performance are modelled and optimised by using the finite-difference time-domain (FDTD) method. The sunlight directly impinges on the solar panel or cells, then a portion of the incident sunlight reflects back to the air from the surface of the panel, thus leading to a reduction in the light absorption capacity of the solar cells. In order to proliferate the light absorption capacity of solar cells nano-grating structures are employed, as they are highly capable of capturing the incident sunlight compared to a conventional (or flat type) solar cell, which results in generating more electrical energy. In this study, we design three different types of nano-grating structures, optimise their parameters and their performance in light capturing capacity. From the simulation results, we confirm that that it is possible to reduce light reflection losses up to 27%, by using the nano-grating structures, compared to conventional type solar cells. This reduction of reflection losses helps to improve the conversion efficiency of next-generation GaAs solar cells significantly for a sustainable green Earth.