ZnS thin films were grown on soda lime glass substrates using spray pyrolisis method at a substrate temperature of 573K. The films were then subjected to a rapid thermal annealing at different temperatures. X-ray diffraction carried out on the films revealed a single peak which increase in intensity with increase in annealing temperature. The patterns of the ZnS thin films showed that the full width at half-maximum (FWHM), micro-strain and dislocation density of the films decreased with increase in annealing temperature, indicative of an improvement of the crystal quality of ZnS films. Similarly the calculated grain size of the films exhibited an increase with increase in annealing temperature which is a clear indication of an improvement of the crystal quality of the ZnS films. The values of lattice constant 'a' agree with the standard and reported values.
Spray pyrolysis technique has been used to deposit Fluorine doped Tin Oxide (FTO) thin films. Optical constants such as refractive index (n), extinction coefficient (K) and the absorption coefficient () of the FTO thin films were determined using spectrophotometric measurement of transmittance, absorbance and reflectance in the spectral range from 172 to 1100nm. The maximum value of transmittance was in the range of 77% to 86%. Furthermore, the effect of annealing temperature and the annealing condition on optical band gap (Eg) was studied. The optical band gap was found to be within the range of 3.50 to 4.0 eV.
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