Effect of substrate temperature on the crystal growth orientation of SnO2:F thin films spray-deposited on glass substrates

Transparent conducting thin films of SnO2:F have been deposited onto preheated glass substrates by a spray pyrolysis technique using dihydrate stannous chloride (SnCl2 center dot 2H(2)O) and ammonium fluoride (NH4F) as precursors, and mixture of water and ethanol as solvent. The preheated substrate temperature was changed from 250 degrees C to 600 degrees C. X-ray diffraction spectra show that the as-deposited films are polycrystalline SnO2 with a tetragonal crystal structure. Surface morphology, optical properties (such as transmission, color), and conductivity were investigated using Super depth of three-dimensional field microscopy system, UV-VIS-NIR spectroscopy, Four-point probe. The obtained results revealed that the structures and properties of the films were greatly affected by substrate temperature. The lowest sheet resistance of 4.0 Omega was obtained with moderate optical transmission (up to 75% at 600 nm). The relationship between the crystal growth orientation and surface morphology, optical properties (such as transmission, color), and electrical properties, was discussed in detail in this article. (C) 2010 Elsevier B.V. All rights reserved.