Electrically conductive anti-reflecting nanostructure for chalcogenide thin-film solar cells

Electrically conducting aluminum (Al)-doped ZnO nanorods (NRs) film has been introduced as an anti-reflective (AR) layer for effective light trapping in chalcogenide thin-film solar cells. Results indicate that the Al-doping significantly reduced the electrical contact resistance between the Ag top electrode and the AR layer. The Al-doped ZnO NRs exhibited low average reflectance (4.5%) over the entire visible and near-infrared range, and changed the nature of electrical contact between the Ag electrode and the AR layer from Schottky to Ohmic. Finally, the CuInS₂ solar cell coated with the Al-doped ZnO NRs exhibited huge enhancement in photovoltaic efficiency from 9.57% to 11.70% due to the lowering series resistance and the increase in the short-circuit current density, when compared with that of a solar cell without the AR layer.