Silicon nanohole based enhanced light absorbers for thin film solar cell applications

Abstract

We proposed a nanohole-based silicon (Si) absorber structure to enhance the light absorption of thin-film Si solar cells. Our proposed structures exhibited excellent performances harnessing the light-matter interaction phenomenon with a few microns of thick Si (3 µm). We employed the finite-difference time-domain method to analyze the optical properties and solved Poisson’s, continuity, and heat transfer equations to analyze the electrical and thermal properties of our proposed structures, operating in the wavelength range from 300 to 1100 nm. We obtained a maximum average absorption of 72.6% for our proposed square hole Si absorber structure. The power conversion efficiency and short circuit current density were calculated to be 20.74% and 39.91 mA/cm2. We achieved polarization-insensitive performance due to the symmetrical nature of the structure. The temperature of our proposed structure was increased by ∼10 K due to light absorption for different ambient temperatures. Moreover, we found our proposed structure was thermally stable over time. Our proposed structures can enhance the absorption of Si nanostructures, which can be conducive to designing Si-thin solar cells for energy harvesting.