Indium tin Oxide (ITO) coatings fabricated using mixed ITO sols

Abstract

ITO films were achieved by sintering at 500∼550°C. This was possible by inducing a seeding effect on an ITO sol by producing crystalline ITO nanoparticles in situ during heat treatment. Two kinds of ITO sols (named ITO-A and ITO-B) were prepared at 2.0 wt% from indium acetate and tin(IV) chloride in different mixed solvents. The ITO-A sol showed a high degree of crystallinity of ITO without any detectable SnO2 on XRD at 350°C/1 h, but the ITO-B sol showed a small amount of SnO2 even after annealing at 600°C/1 h. The 10 wt% ITO-A//ITO-B showed the sheet resistance of 3600Ω/□ , while the ITO-B sol alone showed 5200 Ω/□ by sintering at 550oC for 30 min. Processing parameters were studied by TG/DSC, XRD, SEM, sheet resistance, and visible transmittance.