Absorption enhancement in amorphous silicon photonic crystals for thin film photovoltaic solar cells

TL;DR

This paper demonstrates that photonic crystal structures in amorphous silicon can significantly enhance light absorption, leading to improved efficiency in thin film photovoltaic solar cells, validated through simulation and experimental results.

Contribution

It introduces a novel design of amorphous silicon photonic crystals with slow light modes that boost absorption efficiency, validated by both simulation and experiments.

Findings

Absorption increased by a factor of 1.5 in simulations.

Experimental validation shows significant absorption enhancement.

Effective over a spectral range of 0.32-0.76 microns.

Abstract

We report on very high enhancement of thin layer's absorption through band-engineering of a photonic crystal structure. We realized amorphous silicon (aSi) photonic crystals, where slow light modes improve absorption efficiency. We show through simulation that an increase of the absorption by a factor of 1.5 is expected for a film of aSi. The proposal is then validated by an experimental demonstration, showing an important increase of the absorption of a layer of aSi over a spectral range of 0.32-0.76 microns.