Indium Nanoparticle Enhanced Light Trapping in Thin Film Silicon Solar Cells

Abstract

Plasmonic nanoparticles can be engineered to achieve light trapping and get the full potential of thin film solar cells. This paper presents indium (In) nanoparticle based plasmon enhanced light trapping mechanism for thin film silicon solar cells. With the light trapping at the front, at the rear or at both surfaces of the solar cell along with a thin silicon nitride (Si3N4) antireflection coating, surface transmittance, reflectance and absorption enhancement of incident light were studied. In all the cases indium nanoparticle based light trapping resulted in more light absorption implying more photocurrent generation but the geometry and position of the nanoparticles determine the scattering and coupling properties. Therefore, optimization of indium nanoparticle diameter and inter-particle spacing was performed. Compared to more commonly used (but highly expensive) gold nanoparticles, indium nanoparticles based light trapping performed well in every aspect. These demonstrate the suitability of indium nanoparticles for light trapping in the thin film silicon solar cells, particularly in deep ultraviolet (UV) and near visible regions.