Fiber laser-assisted room-temperature crystallization of solution-processed indium-rich IGO thin films for high-performance, high-reliability thin-film transistors

Abstract

Solution-processed nanocrystalline oxide semiconductors offer great potential for next-generation displays and sensors owing to their excellent large-area uniformity, compatibility with low-cost fabrication techniques, and superior electrical performance compared to the amorphous phase. However, the typical trade-off between high electron mobility and bias stability of oxide semiconductor-based thin-film transistors (TFTs) remains a key obstacle to developing high-performance devices for practical applications. Herein, 355 nm fiber laser irradiation is introduced as an effective strategy to simultaneously enhance mobility and bias stability in solution-processed indium gallium oxide (IGO) thin films. The composition of IGO was optimized at 7.5% Ga incorporation for efficient 355 nm absorption, facile crystallization, and suppression of oxygen vacancies. The fiber laser post-treatment on a 7.5% Ga incorporated IGO film induced rapid localized heating, which promoted crystallization of the semiconductor layer within a short timescale and reduced structural disorder. Consequently, the optimized device, irradiated at 50 mJ cm⁻², exhibits a high mobility of 36.74 cm² V⁻¹ s⁻¹ with a threshold voltage close to 0 V, along with excellent electrical stability with threshold voltage shifts of 0.04 V and −1.9 V at a positive and negative bias stress of 2 MV cm⁻¹ for 10 000 s, respectively. These results demonstrate that low-cost fiber laser-assisted post-treatment effectively addresses the mobility–stability trade-off, providing a viable pathway toward high-performance solution-processed oxide semiconductors for next-generation electronic applications.