Preparation and characterisation of nanostructured tin oxide (SnO₂) films by sol–gel spin coating technique

Highly transparent tin oxide thin films (SnO₂) have been prepared using the sol–gel spin coating technique, optimising process parameters such as the solute concentration, spin rate and time of the turn table, film thickness (number of coatings) and heat treatment temperature. The X-ray diffraction (XRD) studies point to the polycrystalline structure of the developed films. The films deposited under optimum conditions are highly transparent in the visible region with a transmittance of 94% at 550 nm and have a resistivity of 3 × 10⁻² Ωcm. The films have been obtained at a relatively low process temperature of 400°C.