All-sputtered oxide thin-film transistors fabricated at 150 °C using simultaneous ultraviolet and thermal treatment

Abstract

In this study, we report all-sputtered In–Ga–Zn–O (IGZO) thin-film transistors (TFTs) through the fabrication of a sputtered gate insulator. Furthermore, using simultaneous UV and thermal (SUT) treatment, we fabricate sputter-processed gate insulators at a low temperature of 150 °C with a higher amount of coordinated oxygen species and a higher surface energy than thermal-only (300 °C) treated gate insulators. Additionally, by activating the IGZO channel layer using SUT treatments, we fabricate all-sputter processed IGZO TFTs at 150 °C and they exhibit improved device performances compared to thermal-only treated ones; the field-effect mobility is increased from 7.32 ± 3.8 to 29.59 ± 2.5 cm² V⁻¹ s⁻¹, the on/off ratio is increased from (1.1 ± 1.8) × 10⁵ to (2.9 ± 1.7) × 10⁸, and the subthreshold swing is decreased from 1.0 ± 0.07 to 0.4 ± 0.05 V dec⁻¹.