Effect of annealing temperature on the electrical properties of IZO TFTs

Abstract

The current international demand for thin-film transistors is growing, and reducing the time and economic cost of production while preparing thin-film transistors with excellent electrical properties will have a profound impact on the future development of thin-film transistors. In this paper, we choose the sol–gel method to prepare IZO TFTs, which can reduce the production cost and cycle time by 60% compared with the preparation method that requires vacuum conditions. Since the annealing temperature has a great influence on the electrical properties of IZO TFTs, in this study, we focus on the effect of different annealing temperatures on the electrical properties of IZO TFT devices, and analyze and study the results of the test results of the film structural properties, optical properties, surface morphology, etc. Ultimately, it was found that IZO TFT devices with excellent electrical properties were obtained when the annealing temperature was 350 °C. The turn-off current (I_off = 2.52 × 10⁻¹³ A), threshold voltage (V_th = 0.8 V), and subthreshold swing (SS = 0.25 V dec⁻¹) were minimized. The highest switching current ratio (I_on/I_off = 1.58 × 10⁷) and high mobility of 28.71 cm² V⁻¹ S⁻¹ were achieved. The average transmittance of the films is as high as 98.96%.