ABSTRACT This study developed an excimer‐light‐assisted solution process using aqueous metal–nitrate precursors and 172 nm deep‐ultraviolet irradiation to fabricate In 2 O 3 and Ga‐doped In 2 O 3 (IGO) thin‐film transistors (TFTs). Photochemical activation enabled precise control of precursor decomposition and film crystallization. Excimer irradiation promoted dehydration–condensation reactions, forming polycrystalline In 2 O 3 at a low processing temperature of 200°C. TFTs annealed at 300°C exhibited an on/off ratio of 4.2 × 10 6 and a field‐effect mobility of 28 cm 2 /Vs. Increasing the annealing temperature to 500°C enhanced the mobility to 106 cm 2 /Vs, indicating improved carrier transport due to enhanced crystallization. With Ga incorporation, high mobility was maintained at 90.8 cm 2 /Vs for 10 mol% Ga and 70.9 cm 2 /Vs for 25 mol% Ga. Hysteresis width and subthreshold swing were significantly reduced, with an improved on/off ratio of 2.0 × 10 7 , demonstrating enhanced operational stability. These improvements are attributed to suppression of oxygen‐vacancy‐related trap states by stronger Ga–O bonds. Gate‐length‐dependent analysis indicates that mobility degradation under high electric fields arises from self‐heating rather than short‐channel effects. These results demonstrate that photochemical control combined with compositional engineering mitigates the mobility–stability trade‐off in In 2 O 3 ‐based TFTs.
Ueda et al. (Thu,) studied this question.