Structural, Morphological and Optical Characterization of SnO₂:F Thin Films Prepared by Chemical Spray Pyrolysis

Fluorine doped tin oxide (FTO) films were successfully prepared on glass and quartz substrate at a substrate temperature equal to 450 °C for different fluorine doping (0, 0.05, 0.1, 0.15) by a homemade spray pyrolysis technique. The spray solution prepared from tin tetrachloride pentahydrate (SnCl_{4 · 5H2}O) dissolved in distilled water at (0.1 M) concentration and ammonium fluoride (NH₄F) was added into the solution for fluorine doping. X-ray diffraction patterns of the spray-deposited (SnO₂: F) films for different fluorine doping show that all the diffractograms contain the characteristic SnO2 orientations. The matching of the observed and standard d-values confirm that the deposited films are of tin oxide with tetragonal structure and the films are polycrystalline with (110) as a preferred growth orientation. The surface morphology of SnO₂: F thin film has been examined by atomic force microscopy (AFM). The average transmittance in the visible region (at 550 nm) has been found (40%, 47%, 52%, 59%, 61%) for the fluorine doping (0, 0.05, 0.1, 0.15, 0.2) respectively.