A low-temperature method for improving the performance of sputter-deposited ZnO thin-film transistors with supercritical fluid

Abstract

A low-temperature method, supercritical CO 2 ͑SCCO 2 ͒ fluid technology, is employed to improve the device properties of ZnO TFT at 150°C. In this work, the undoped ZnO films were deposited by sputter at room temperature and treated by SCCO 2 fluid which is mixed with 5 ml pure H 2 O. After SCCO 2 treatment, the on/off current ratios and threshold voltage of the device were improved significantly. From x-ray photoelectron spectroscopy analyses, the enhancements were attributed to the stronger Zn-O bonds, the hydrogen-related donors, and the reduction in dangling bonds at the grain boundary by OH passivation.

Reduction of defect formation in amorphous indium-gallium-zinc-oxide thin film transistors by N2O plasma treatment

“…Moreover, amorphous oxide semiconductor-based materials are expected to be adopted as nonvolatile memory devices. 2,[15][16][17] In order to achieve practical application of a-IGZO TFTs in active-matrix backplanes of future generations of large active-matrix liquid-crystal displays (AMLCDs) and organic light-emitting diode panels (OLEDs), some problems still remain to be improved, such as the forming of sub-threshold leakage current at high temperature, instability under light illumination, [18][19][20][21][22] and uncertainty over environmental change. [23][24][25][26][27] In this study, we investigate the temperature dependence of a-IGZO TFTs using energy band diagrams.…”

Competing weak localization and weak antilocalization in amorphous indium–gallium–zinc-oxide thin-film transistors

“…An intriguing controllable competition between weak localization and weak antilocalization is observed by tuning the gate voltage or varying the temperature. Our findings reflect controllable quantum interference competition in the electron systems in amorphous indiumgallium-zinc-oxide thin-film transistors.Amorphous metal-oxide semiconductors have recently been studied for applications in thin-film transistors (TFTs) for large-area flexible electronics because of their electrical uniformity and fabrication advantage of roomtemperature deposition and patterning [1][2][3][4]. In particular, zinc oxide (ZnO) has recently attracted intense experimental and theoretical attention owing to its potential use in the emerging nanoelectronics and optoelectronics [5][6][7].…”

Reduction of the interfacial trap density of indium-oxide thin film transistors by incorporation of hafnium and annealing process

“…Thin film transistors based on amorphous oxide films (OxTFTs) have attracted tremendous interest as TFT backplanes in active-matrix organic light emitting diodes (OLEDs) and liquid crystal displays owing to their high mobilities. [1][2][3][4][5][6][7] Intensive developments on oxide compounds including InO x -based, [8][9][10][11][12][13] ZnO x -based, 14 SnO x -based 15 and mixed channel materials such as InZnO x -based OxTFTs [16][17][18][19][20][21][22][23][24][25] have been widely studied in OxTFTs in recent decades because of their excellent electrical stabilities and high mobilities. Among them, InGaZnO (IGZO) 1,2,26 and InSnZnO (ITZO) 18,19 are currently being developed for use as commercial TFT backplanes because of their superior properties and high electron mobilities.…”