Influences of Organic Ligands on the Microstructure and Properties of Sol-Gel Antimony-Doped Tin Oxide Thin Films

The antimony-doped tin oxide (ATO) thin films were prepared by sol-gel dip-coating process from SnCl(2)center dot 2H(2)O and SbCl(3) in alcoholic solutions. The influences of organic ligands, including acetic acids (HAc), acetic acids with monoethanolamine (in brief HAc+MEA), and acetic acids with acetylacetone (in brief HAc AcAc), on the the microstructure and electrical properties of the thin films have been investigated. The thermal behavior of the ATO gels powders and the microstructures of the thin films have been characterized by using thermogravimetric (TG), differential scanning calorimetric (DSC), Fourier transform infra-red spectral (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) analysis. The electrical resistivity of the thin films was detected by four-probe instrument measurement. The thin films with HAc+MEA as coordination ligands had a good crystal quality and showed a preferred orientation along (101) plane when heated at 450 degrees C. As a consequence, it exhibited the best electrical performance. An electrical resistivity of about 6.3 x 10(-3) Omega . cm could be achieved for the films with 500 nm thickness.