Capacitance–Voltage Characteristics Analysis of Indium Zinc Oxide Thin Film Transistors Based Ultraviolet Light Irradiation

: The mechanism of solution-processed indium zinc oxide (IZO) thin film transistors (TFTs) made by simultaneous spin coating and ultraviolet (UV) light irradiation was investigated by capacitance-voltage (C-V) measurement. The application of UV light on the IZO TFTs was found to improve the thin film surface structure, and pledge to receive low degree of roughness. Meanwhile, electrical characteristics indicated that the TFT prepared at the UV light irradiation with 90 s exhibits the best performance with field-effect mobility 5.6 cm²/Vs, threshold voltage ═ -0.13 V, subthreshold gate swing 0.64 V/decade and on/off ratio ═ 1.7 × 106. In the C-V contrastive analysis with different UV light irradiation time by 60 s and 90 s, the frequency was varied from 100 Hz to 10 kHz to investigate low as well as high frequency C-V.