Transformation of amorphous iron oxide thin films predeposited by spray pyrolysis into a single FeSe2-phase by selenisation

摘要

The present paper investigates a simple and non-toxic method to transform amorphous iron oxide pre-deposited by spray pyrolysis of FeCl3. 6H(2)O (0.03 M)-based aqueous solution onto glass substrates heated at 350 degrees C into FeSe2 thin films. The amorphous iron oxide films were heat treated under a selenium atmosphere (10(-4) Pa) at different temperatures for 6 h. X-ray diffraction (XRD) was used to investigate the structure of the obtained films. Single FeSe2-phase films having good crystallinity were obtained at a selenisation temperature of 550 degrees C. Optical analyses of the FeSe2 films obtained at 550 degrees C enabled us to deduce a large absorption coefficient (alpha > 10(5) cm(-1), lambda < 800nm). Surface scanning electron microscopy (SEM) observations show inhomogeneous films. Electrical conductivity of the as-prepared films was measured at high and low temperatures. (c) 2004 Elsevier B.V. All rights reserved.