Tin-doped indium oxide thin films deposited by sol-gel dip-coating technique

Indium tin oxide (ITO) thin films were prepared by the sol-gel dip-coating (SGDC) technique. The microstructure and electrical properties of ITO thin films crystallized using rapid thermal annealing (RTA) were compared with those of films prepared by classic thermal annealing (CTA). ITO thin films were successfully prepared by CTA at 500 degreesC for 30-60 min. AT the same temperature of 500 degreesC and with a 6 min RTA treatment, the film exhibits electrical resistivity values close to the CTA ones. The crystalline structure of the ITO films was visualized by high-resolution transmission electron microscopy (HRTEM) and electron diffraction patterns compared with that of pure In2O3. The average grain size, measured from TEM micrographs, ranges from 5 to 20 nm. The process of film densification was also followed by Rutherford backscattering spectrometry (RBS).