A combined experimental-computational study on nitrogen doped Cu₂O as the wide-spectrum absorption material

Highly-oriented Cu₂O thin films were prepared by low temperature thermal oxidation of evaporated Cu thin films. The films were doped with different doses of nitrogen by ion implantation. An absorption peak appears below the absorption edge in the absorption spectrum of highly nitrogen doped Cu₂O. The effect of nitrogen doping on the crystal structure, electronic structure and optical properties of Cu₂O were investigated systematically by first-principles calculations. The calculation results indicate that an intermediate energy band exists in the forbidden gap of highly nitrogen doped Cu₂O. The electron transition from the valence band to the intermediate band is consistent with the absorption peak by experimental observation. Experimental and computational results indicate that nitrogen doped Cu₂O could be a suitable absorbing material candidate for wide-spectrum detectors or intermediate band solar cells. (semiconductor materials)