Electrodeposition of CuInSe2 from ethylene glycol at 150 degrees C

Polycrystalline chalcopyrite thin films were potentiostatically electrodeposited from ethylene glycol Solution onto SnO2-coated glass substrates at 150 degrees C. The thickness of the layers was estimated using talysurf at 1.0 mu m after deposition for 60 min. X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyses were used to identify and characterise compounds formed at different potentials. It was found that Cu1.75Se formation was dominant at -0.80V vs Se and indium assimilation increased at more negative voltages forming a mixture of compounds including numerous Cu-Se binary phases and copper indium diselenide (CuInSe2) at the cathode. As-deposited materials showed poor crystallinity and therefore films were annealed in Ar/5%H-2 in the presence of Se to improve the material quality for all investigations. Although the films were deposited at 150 degrees C, no noticeable improvement of the CuInSe2 was observed, suggesting growth from aqueous media at room temperature to be preferable. (C) 2009 Elsevier B.V. All rights reserved