Low-temperature rapid preparation of high-performance indium oxide thin films and transistors based on solution technology

Indium oxide (In2O3) thin films and thin-film transistors (TFTs) based on the solution process are prepared by pulsed UV-assisted thermal annealing at a low temperature (200 degrees C) 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 are investigated, and they are compared with those of conventional thermal annealing (300 degrees C, 30 min). The experimental results show that the pulsed UV-assisted thermal annealing method can improve the quality of In2O3 thin film and the performance of TFT in a short period. The results of atomic force microscopy and field emission scanning electron microscopy show that the surface of the In2O3 film is denser and flatter than that of the conventional thermally annealed film, and X-ray photoelectron spectroscopy 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 film. In addition, the effect of pulsed UV-assisted thermal annealing on the electrical characteristics of In2O3 TFTs is investigated in a comparative way. The results show that the electrical characteristics of the device are significantly improved: the subthreshold swing decreases to 0.12 mV/dec, the threshold voltage is 7.4 V, the current switching ratio is as high as 1.29x10(7), and the field effect mobility is enhanced to 1.27 cm(2)center dot V-1 center dot s(-1). Therefore, pulsed UV-assisted thermal annealing is a simple and fast annealing method, which can rapidly improve the performances of In2O3 thin film and TFTs, even under low-temperature conditions.