In2O3/CdS/CuInS2 thin-film solar cell with 9.7% efficiency

An efficient thin-film photovoltaic cell has been fabricated using the heterostructure consisting of a CuInS2 film obtained by sulfurization of a metallic precursor, a chemical-bath-deposited CdS layer, and an atom-beam-sputtered In2O3 film. A preceding KCN treatment of the Cu-rich CuInS2 film lowered the Cu/In ratio and raised the resistivity. A cell conversion efficiency of 9.7% (active area efficiency>10%) at air mass 1.5 has been achieved without antireflection coatings.