Effect of fluorine doping on the structural, optical and electrical properties of spray deposited cadmium stannate thin films

Cadmium stannate (Cd2SnO4) thin films were coated on Corning 1737 glass substrates at 540 degrees C by spray pyrolysis technique, from the aqueous solution of cadmium acetate and tin (II) chloride precursors. Fluorine doped Cd2SnO4 (F: Cd2SnO4) thin films were prepared by adding ammonium fluoride in the range of 0-5 wt% of the total weight of cadmium acetate and tin (II) chloride in the spray solution. Thickness of the prepared films is about 300 nm. X-ray diffraction analysis of the Cd2SnO4 and 3 wt% F: Cd2SnO4 films shows the signature for the growth along (222) direction. Scanning electron micrographs showed that fluorine doping effectively modifies the surface morphology of Cd2SnO4 films. Average optical transmittance in the visible region (500-850 nm) for Cd2SnO4 is similar to 79% and it is increased to similar to 83% for 1 wt% doping concentration of the NH4F in the solution. Fluorescence spectra of F: Cd2SnO4 (1 wt% and 3 wt%) exhibit peak at 601 nm. F: Cd2SnO4 film (1 wt%) shows mobility of similar to 42 cm(2)/V s, carrier concentration of similar to 9.5 x 10(19) cm(-3) and resistivity of similar to 1.5 x 10(-3) Omega cm. (C) 2013 Elsevier Ltd. All rights reserved.