Fabrication of indium–tin-oxide films by dip coating process using ethanol solution of chlorides and surfactants

Highly-conductive ITO transparent films were deposited by the dip coating process. An ethanol solution of indium (III) chloride, InCl3·3.5H2O, and tin (II) chloride, SnCl2·2H2O [Sn/(In+Sn), 5 at.%] was successfully dip coated on a Corning #7059 glass substrate by the addition of a surfactant [Sorbon T-80 (non-ionic type); polyoxyethylene sorbitan fatty acids esters]. The dip coating (withdrawal rate, 10 or 28 cm/min) and the heating in air at 600 °C for 1 h were repeated 10 times to fabricate the ITO film with a resistivity of approximately 2×10−3 Ω·cm. Post-deposition annealing in a N2–0.1% H2 atmosphere drastically lowered the resistivity to approximately 2.5×10−4 Ω·cm. This value is lower than most of the reported minimums (4×10−4 Ω·cm) for the thicker ITO films fabricated by the dip coating process.