Facile Room Temperature Routes to Improve Performance of IGZO Thin-Film Transistors by an Ultrathin Al2O3 Passivation Layer.

Although oxide thin-film transistors (TFTs) have drawn great interests in flexible displays, a key obstacle is the requirement of high-temperature annealing to realized mobility >10 cm²/V · s. In this paper, a fully room-temperature strategy, involving the deposition of ~10 nm In-Ga-Zn-O (IGZO) channel layer and ~4 nmAl2O3 passivation layer, is introduced. The as-prepared flexible TFT on polymide substrate exhibits a saturation mobility of 15.3 cm²/V · s, Vth of 3.08 V, and on/off current ratio of 2.3 x 107. Thickness-dependent analysis indicates that the interface between Al2O3 and IGZO is composed of negative O-rich layer, which impel the energy band bending inside the IGZO layers and release of electrons from traps. This paper opens up a route to achieve fully room-temperature fabrication of high-performance flexible TFT. [ABSTRACT FROM AUTHOR]