The status and perspectives of metal oxide thin-film transistors for active matrix flexible displays

Abstract

The purpose of this paper is to give an overview of the state-of-the-art of metal oxide thin-film transistors (TFTs). First, the question of how to achieve high-performance oxide TFTs is addressed, including the exploration of new channel materials, the realization of low-resistance ohmic contacts and the implementation of high-k dielectric materials as the gate insulator. The electrical instability of the oxide TFTs is also discussed, which is critical for their application in flexible backplane electronics: special attention is given to the understanding of the degradation mechanism of oxide TFTs against bias thermal stress (BTS) and light illuminated BTS. Finally, the recent application of oxide TFTs in active matrix displays, such as electronic paper, liquid crystal displays and organic light-emitting diodes, is addressed.

Large-scale complementary macroelectronics using hybrid integration of carbon nanotubes and IGZO thin-film transistors

“…However, the environmental and operational stability of organic TFTs still remains an important issue to be addressed for their usage in practical macroelectronic applications 3,5,9,10 . Oxide semiconductor TFTs such as IGZObased TFTs have been successfully employed in pixel driver circuitry for commercial display applications 4,[11][12][13][14] . Despite the advancement in oxide semiconductor TFT technology, oxide semiconductor thin films are usually n-type materials, and it still remains a challenge to produce stable p-type oxide TFTs with high effective TFT mobility for macroelectronics 4,15,16 .…”

Atomic layer deposited zinc tin oxide channel for amorphous oxide thin film transistors

“…[1][2][3] The large demand for low power consumption with better performance of such devices requires a new semiconductor material exhibiting better transistor properties, i.e. higher mobility, smaller subthreshold swing (SS), higher ratio of on-to-off drain current (I ON /I OFF ).…”

“…In order to achieve these highly desirable properties for ALD of multicomponent amorphous oxides, the ALD 3 temperature windows of the different components must overlap. For example, diethyl zinc, the most popular zinc precursor in ZnO-ALD, exhibits an ALD window from roughly 120 to 170 o C. Therefore, an ALD process for SnO 2 showing an overlapping ALD temperature window should be used to realize ideal ALD of ZTO. Recently the authors have demonstrated low-temperature (60-250 o C) ALD of tin dioxide, SnO 2 , using a cyclic amide of Sn(II) (1,3-bis(1,1-dimethylethyl)-4,5-dimethyl-(4R,5R)-1,3,2-diazastannolidin-2-ylidene) as the tin precursor.…”

“…This result suggests that fabrication of ALD-based ZTO transistors is compatible with most electronic device applications including some polymer substrates. Further improvement in the mobility of the transistors may be achieved by using a zinc precursor, such as zinc acetate (Zn(CH 3 COO) 2 ), that is thermally stable at higher growth temperatures above 170 o C . 27 The drive current density per unit width could be increased by depositing the transistors conformally over highly patterned substrates, such as arrays of parallel narrow trenches.…”

Overview of electroceramic materials for oxide semiconductor thin film transistors

“…Oxide semiconductors have, in recent years, become the focus of extreme interest for emerging electronic applications, such as flexible and transparent displays [1][2][3][4][5]. In particular, several display industries have intensively researched and demonstrated advanced flat-panel display (FPD) technology utilizing oxide semiconductors including electronic paper (e-paper), organic light-emitting diode displays (OLEDs) and liquid crystal displays (LCDs) [6,7].…”