Preparation of precursor solutions for ITO thin film formation by a reaction of glucose with In (Ⅲ) alkoxide and Sn(Ⅱ) halogenides

摘要

The precursor solutions for ITO thin film formation were prepared by a reaction of glucose with an indium triisopropoxide and tin halogenides in alcohol, under the presence of HNO_3. The solution was stable and could be spin-coated on a quartz glass with excellent coatability. Transparent and crack-free ITO thin films were formed by firing the precursor films at above 550°C in air for 30 min. A resistivity of 5 x 10~(-3)Ωcm was observed for the double-layered ITO thin film of cubic structure and of ca. 140 nm thickness. Quartz glass with the film was transparent with the transmittance of above 81 % in the visible region. The mean crystallite size of the ITO films was evaluated from line broadening of (222) XRD peak of the ITO thin film using Scherrer's equation. It was clarified that the crystallite size of the oxides and firing temperature affect strongly on the electrical property of the thin films.