Low-Temperature Rapid Preparation of High-Performance Indium Oxide Thin Films and Transistors Based on Solution Process

Indium oxide (In₂O₃) thin films and thin-film transistors (TFTs) based on the solution process were prepared by pulsed UV-assisted thermal annealing at a low temperature of 200 for 5 min. The effects of pulsed UV-assisted thermal annealing on the surface morphology, chemical structure, and electrical properties of the In₂O₃ thin films were investigated in comparison with conventional thermal annealing (300, 30 min). The experimental results show that the pulsed UV-assisted thermal annealing method can improve the quality of In₂O₃ thin films and the performance of TFTs in a short period. Atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) results show that the surface of the In₂O₃ films is denser and flatter than that of the conventional thermally annealed films, and X-ray photoelectron spectroscopy (XPS) tests show that the pulsed UV-assisted thermal annealing process generates oxygen vacancies, which increases the carrier concentration and improves the electrical conductivity of the In₂O₃ films. In addition, the effect of pulsed UV-assisted thermal annealing on the electrical characteristics of In₂O₃ TFTs was comparatively investigated. The results showed that the electrical characteristics of the devices are significantly improved, with the subthreshold swing reduced to 0.12 mV·dec^-1, the threshold voltage is 7.4 V, the current switching ratio is as high as 1.29×10⁷, and the field effect mobility is enhanced to 1.27 cm ² ·V^-1s^-1. Therefore, pulsed UV-assisted thermal annealing is a simple and fast annealing method, which can rapidly improve the performance of In₂O₃ thin films and TFTs, even under low-temperature conditions.