Preparation of CuInSe2 thin films by pulsed laser deposition the Cu–In alloy precursor and vacuum selenization

CuInSe2 (CIS) films were prepared by pulsed laser deposition (PLD) Cu–In alloy precursors on Mo-coated sodalime glass substrates and vacuum selenization. Cu–In alloy precursors showed the dominant Cu11In9 phase and all the selenized CIS films showed the single chalcopyrite structure with preferred (112) orientation by XRD method. The cross-sectional morphology was observed by SEM. The composition of the CIS films was also measured by XRF. The crystallized films showed Raman spectra with a dominant A1 mode at 174 cm−1, generally observed in I–III–V I2 chalcopyrite compounds and no additional peak at 258 cm−1 which was observed in other reports. An energy band gap of about 0.95 eV and an absorption coefficient near 105 cm−1 were obtained by absorption spectroscopy measurement.