ELECTRODEPOSITION OF CUINS2 FROM AQUEOUS-SOLUTION .2. ELECTRODEPOSITION OF CUINS2 FILM

Copper indium disulphide, CuInS2 thin films were successfully prepared by electrodeposition without usual heat treatment in H2S atmosphere. Thin films were deposited from acidic aqueous solution containing CuSO 4, In-2(SO4)(3) and Na2S2O3 at -0.9 V vs. Ag/AgCl for 300-1200 s. Sing le phase CuInS2 films were obtained at pH about 1.5 by the correct adj ustment of the Cu2+/In3+ ratio, with the concentration of Na2S2O3 fixe d at 400 mM. Well-crystallized films were obtained by annealing in vac uum at 673 K. From EDX analysis, it was found that the compound CuInS2 did not always exist in exact stoichiometry of Cu:In:S = 1:1:2. The c onduction type of the film changed from p to n in the indium-rich regi on. This result suggests the possibility of controlling the properties of thin films by varying the concentration of each chemical in the in itial electrolytic solution.