Characterization of stepwise flash-evaporated CuInSe<inf>2</inf> films

CuInSe2 (CIS) films were deposited by stepwise flash evaporation from polycrystalline powder source onto glass substrates held at various temperatures ranging from 100 to 560K. The phase purity and microstructure were analyzed by transmission electron microscopy. The investigations show that films grown at 300K and below were amorphous, whereas those grown at 370K and above were polycrystalline in nature. The grain size in polycrystalline films were found to improve with increase in substrate temperature and during post-deposition annealing. The films had near stoichiometric composition as revealed by Rutherford backscattering spectrometry. Analysis of the optical transmittance spectra of CIS films deposited at 520K yielded a value of ∼0.97eV for the fundamental band gap. © 2004 Elsevier Ltd. All rights reserved.