Patent ID: 8841160

Claim:
A method for producing a chalcopyrite compound thin film, the method comprising (a) mixing a first metal precursor, a first organic binder, and a first water-soluble solvent to obtain a first paste, (b) mixing a second metal precursor, a second organic binder, and a second water-soluble solvent to obtain a second paste, (c) coating the first paste on a conductive substrate to form a first paste layer, (d) coating the second paste on the first paste layer to form a second paste layer, (e) thermally treating the coated conductive substrate in air or an oxygen atmosphere to obtain a mixed oxide thin film, and (f) thermally treating the mixed oxide thin film in a sulfur gas, a selenium gas or a sulfur/selenium mixed gas atmosphere to form a sulfide or selenide thin film, wherein the first metal precursor and the second metal precursor are identical to or different from each other and are each independently a precursor of one or more Group IB metals, a precursor of one or more Group IIIA metals, or a mixture thereof, the precursor of one or more Group IB metals and the precursor of one or more Group IIIA metals are each independently included in either the first metal precursor or the second metal precursor or both of them, the first water-soluble solvent and the second water-soluble solvent are identical to or different from each other and are each independently selected from water, alcohol, acetone, and mixtures thereof, the first organic binder and the second organic binder are identical to or different from each other and are each independently selected from ethyl cellulose, polyvinyl acetate, palmitic acid, polyethylene glycol, polypropylene glycol, polypropylene carbonate, propylenediol, and mixtures thereof, and the conductive substrate is made of indium tin oxide, fluorine-doped indium tin oxide, glass, Mo-coated glass, a metal foil, a metal plate, a conductive polymer material, or a mixture thereof, or is a non-conductive substrate coated with indium tin oxide, fluorine-doped indium tin oxide, glass, Mo-coated glass, a metal foil, a metal plate, a conductive polymer material or a mixture thereof.