Lithography free method to synthesize the ultra-low reflection inverted-pyramid arrays for ultra-thin silicon solar cell

TL;DR

This paper introduces a cost-effective, lithography-free method using modified metal assisted chemical etching to create ultra-low reflection inverted pyramid arrays, enhancing ultrathin silicon solar cell efficiency.

Contribution

A novel, simple, and inexpensive fabrication technique for inverted pyramid arrays that allows precise control over structure and significantly reduces reflection.

Findings

Reflection as low as < 0.5% achieved

Predicted solar cell efficiency exceeds Lambertian limit

Method enables cost-effective production of high-performance nanostructures

Abstract

Silicon inverted pyramids arrays have been suggested as one of the most promising structure for high-efficient ultrathin solar cells due to their ability of superior light absorption and low enhancement of surface area. However, the existing techniques for such fabrication are either expensive or not able to create appropriate structure. Here, we present a lithography free method for the fabrication of inverted pyramid arrays by using a modified metal assisted chemical etching (MACE) method. The size and inter-inverted pyramids spacing can also be controlled through this method. We used an isotropic chemical etching technique for this process to control the angle of etching, which leads to ultra-low reflection, even < 0.5%, of this nanostructure. Using this specification, we have predicted the expected solar cell parameters, which exceeds the Lambertian limit. This report provides a new pathway to improve the efficiency of the ultrathin silicon solar cells at lower cost.