# Design and optimization of CIGS-based solar cell with surface dielectric nanostructures arrangement

## TL;DR

This paper presents a new design for CIGS solar cells using dielectric nanostructures to improve efficiency and reduce costs.

## Contribution

A novel cubic AlAs nanoparticle design is introduced, achieving higher absorption and efficiency in CIGS solar cells.

## Key findings

- Cubic AlAs nanoparticles achieved 93.5% average absorption, a 31.7% improvement over the baseline.
- The cubic design's power conversion efficiency reached 17.6%, up from 12.56% in conventional designs.
- The approach offers cost-effective, high-efficiency solar cells with reduced material usage.

## Abstract

This study introduces a novel design of copper indium gallium selenide (CIGS) thin-film solar cells by incorporating aluminum arsenide (AlAs) dielectric nano-particles on the front surface. Three nanoparticle geometries-cubic, cylindrical, and spherical—are explored to enable broadband light absorption and enhance overall device efficiency. The optimization of structural parameters is performed using the particle swarm optimization (PSO) algorithm in conjunction with the Lumerical finite-difference time-domain (FDTD) solver. Simulation results demonstrate that the cubic nanoparticle design delivers the highest performance, achieving an average absorption of 93.5%, corresponding to 31.7% improvement over the baseline cell. The enhanced performance of cubic AlAs nano-particles arises from their support of broadband, high-order Mie resonances, enabled by sharp edges and flat facets. Considering recombination mechanisms, the power conversion efficiencies (PCEs) of the proposed cubic-based structures are enhanced to 17.6%, compared to the conventional design of 12.56%. The reported surface-integrated dielectric nanostructure approach demonstrates strong potential for high-efficiency thin-film solar cells (TFSCs) with reduced material usage, lower fabrication complexity, and cost-effectiveness.