Pulse electrodeposited copper indium sulfide films

Copper indium sulfide (CISu) films were deposited by the pulse galvanostatic deposition technique at different duty cycles. The films are polycrystalline with peaks corresponding to the chalcopyrite phase of CISu. The grain size and surface roughness increased from 10 to 25 nm and 0.85 to 2.50 nm respectively with increase of duty cycle. Optical band gap in the range of 1.30–1.51 eV was observed for the films deposited at different duty cycles. Room temperature resistivity of the films is in the range of 0.1–3.67 Ω cm. Photoconductivity measurements were made at room temperature. Photocurrent spectra exhibited maximum corresponding to the band gap of copper indium sulphide. CdS/CuInS2 fabricated with CISu films deposited at 50% duty cycle have exhibited a Voc of 0.62 V, Jsc of 16.30 mA cm−2, FF of 0.71 and efficiency of 7.16%.