Application of hydrogen-doped In2O3 transparent conductive oxide to thin-film microcrystalline Si solar cells

Hydrogen-doped In2O3 (IO:H) films with high electron mobility and improved near-infrared (NIR) transparency have been applied as a transparent conducting oxide (TCO) electrode in substrate-type hydrogenated microcrystalline silicon (μc-Si:H) solar cells. The incorporation of IO:H, instead of conventional Sn-doped In2O3, improved the short-circuit current density (Jsc) and the resulting conversion efficiency. Optical analysis of the solar cells and TCO films revealed that the improvement in Jsc is due to the improved spectral sensitivity in the visible and NIR wavelengths by reduction of absorption loss caused by free carriers in the TCO films.