Design and analysis of light trapping in thin-film gallium arsenide solar cells using an efficient hybrid nanostructure

Abstract

Light trapping in thin-film solar cells is important for improving efficiency and reducing cost. We propose a hybrid nanostructure based on the anodic aluminum oxide grating and Si 3 N 4 double-layer antireflection coatings combined with Ag nanoparticles to achieve advanced light trapping property in gallium arsenide (GaAs) solar cells with 500-nm thickness. The finite-element method is used to study the relationship between geometrical parameters of hybrid nanostructure and optical characteristics of thin-film GaAs solar cells. The light trapping ability is systematically studied by COMSOL multiphysics. The simulation results show that the hybrid nanostructure can highly increase the light absorption in the wavelengths from 300 to 860 nm. The average absorption in 500-nm-thick GaAs layer is 96.7%. The short circuit current density in 500-nm-thick GaAs layer is 30.2 mA / cm 2 , representing a 58.9% enhancement compared with that ( 19.0 mA / cm 2 ) of the reference cell. Research paves the way for designing highly efficient light trapping structures in thin-film GaAs solar cells.