(Graph Presented) Amorphous indium tin oxide (ITO)-based thin-film transistors (TFTs) were fabricated on various dielectrics [SiO2 and self-assembled nanodielectrics (SANDs)] by spin-coating an ITO film precursor solution consisting of InCl3 and SnCl4 as the sources of In3+ and Sn4+, respectively, methoxyethanol (solvent), and ethanolamine (base). These films can be annealed at temperatures Ta < 250°C and afford devices with excellent electrical characteristics. The optimized [In3+]/[In3+ + Sn4+] molar ratio (0.7) and annealing temperature (Ta = 250°C) afford TFTs exhibiting electron mobilities of ∼2 and ∼10-20 cm2 V -1 s-1 with SiO2 and SAND, respectively, as the gate dielectric. Remarkably, ITO TFTs processed at 220°C still exhibit electron mobilities of >0.2 cm2 V-1 s-1, which is encouraging for processing on plastic substrates.
ASJC Scopus subject areas
- Colloid and Surface Chemistry