(Invited) Reliability Enhancement of High-Mobility Amorphous Indium-Tungsten Oxide Thin Film Transistor

Abstract

In this work, a high-mobility amorphous In-W-O thin transistor (a-IWO TFT) is studied for flat panel displays applications. The effects of oxygen content on the electrical performance and reliability of a-IWO TFTs are mainly investigated by modulating oxygen partial pressure during IWO channel deposition. Experimental results show the high oxygen partial pressure will degrade the electrical stability and cause a large threshold voltage shift (∆ ) in the a-IWO TFT device. To elucidate the origin of electrical instabilities, the interface trap densities, , at the interface between gate insulator and IWO layer as well as bulk trap density, , in the bulk of IWO film were extracted for comparisons. It shows that the interface states are increased as increasing oxygen partial pressures. The enhanced trapping of electron due to the increased interface states is considered to lead to large ∆ in the TFT with increasing oxygen partial pressures.

Si-incorporated amorphous indium oxide thin-film transistors

“…[61][62][63][64] Although there have been several studies on IWO electrodes for organic light-emitting diodes, 65) organic solar cells, 66) and flexible carbon-nanotube transistors, 67) reports focusing on the significant semiconducting properties of this material are limited. [68][69][70][71] Figure 1(a) shows a schematic TFT structure. The inset is a roughness profile of the IWO film observed by AFM after annealing 3 times at 100 °C for 5 min in N 2 using rapid thermal anneal equipment.…”