High Mobility and Excellent Stability of Solution-Processed Heterojunction-Channel IGO/AIGO TFT

Abstract

Achieving high mobility and stability in IGO-based thin film transistors is vital for practical applications in relevant display fields. In this work, we report the heterojunction-channel InGaO/AlInGaO (IGO/AIGO) TFT by a solution process that effectively enhances stability while maintaining high mobility. The large conduction band offset causes electron accumulation at the heterojunction interface, resulting in implementation of the quantum trap, which cooperates with the main electron path to form a double conductive path, as demonstrated by a combination of theoretical and experimental research studies. The IGO/AIGO TFT exhibits a high overall performance, the characteristic parameter including a high mobility of 43 cm²/(V s) that is nearly 4 times higher than the mobility of AIGO TFT (11 cm²/(V s)), and a threshold voltage shift of less than 0.2 V under illumination bias stress after 3600 s. The research results indicate that the oxide thin film transistor we studied, which combines a solution process and heterojunction structure, exhibits significant advantages in the next generation of printed electronic products.