All-sputtered oxide thin-film transistors fabricated at 150 degrees 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 degrees C with a higher amount of coordinated oxygen species and a higher surface energy than thermal-only (300 degrees C) treated gate insulators. Additionally, by activating the IGZO channel layer using SUT treatments, we fabricate all-sputter processed IGZO TFTs at 150 degrees 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 cm(2) V-1 s(-1), the on/off ratio is increased from (1.1 +/- 1.8) x 10(5) to (2.9 +/- 1.7) x 10(8), and the subthreshold swing is decreased from 1.0 +/- 0.07 to 0.4 +/- 0.05 V dec(-1).