High efficiency gallium arsenide solar cells using Indium-Tin-Oxide nano-columns

An array of conductive Indium-Tin-Oxide (ITO) nano-columns is deposited on GaAs solar cells using the oblique-angle electron-beam deposition method. Calculations based on a rigorous coupled-wave analysis method show that such ITO nano-columns offer superior angular and spectral anti-reflective (AR) properties. The optical characteristics of the ITO nano-columns are described. The conversion efficiency of GaAs solar cells with ITO nano-columns as the AR coating is increased by 23%, mainly limited by the quantum efficiency at the wavelengths below 600nm.