Yuzhi Li;Guangshuo Cai;Biao Tang;Shenghan Zou;Linfeng Lan;Zheng Gong
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引用次数: 0
Abstract
In this work, we proposed and demonstrated etch-stopper-layer (ESL) structured indium-gallium-zinc oxide (IGZO) Schottky-barrier thin-film transistors (SBTFTs) with hybrid Ohmic/Schottky contacts utilizing single-layer Cu source/drain (S/D) electrodes. In this unique yet simple configuration, the AlOx layer deposited on the IGZO layer serves not only as a protection layer for the IGZO channel during S/D electrode etching but also as an interfacial layer for modulating the Schottky barrier of the Cu/IGZO contact. This, combined with quasi-Ohmic contact of Cu/IGZO, enables the formation of hybrid contacts based on a single-layer Cu electrode. The ESL-structured SBTFTs with hybrid contacts show a two-order magnitude increase in saturation current (
${I}_{\text {dsat}}$
) compared to SBTFTs solely based on Schottky contacts, with high intrinsic gains exceeding 1500 at a gate voltage of 10 V, and good stability under gate bias and illumination stress. Utilizing technology computer-aided design (TCAD) simulation, the operation of ESL-structured IGZO SBTFTs was fully elucidated. Also, this study conducted a thorough investigation and analysis of the influence of source-drain gaps and Schottky contact lengths at the source on
${I}_{\text {dsat}}$
and saturation voltage (
${V}_{\text {dsat}}$
) for the devices. This work provides a promising route to fabricate low-cost metal oxide SBTFTs with significantly increased
${I}_{\text {dsat}}$
.
期刊介绍:
IEEE Transactions on Electron Devices publishes original and significant contributions relating to the theory, modeling, design, performance and reliability of electron and ion integrated circuit devices and interconnects, involving insulators, metals, organic materials, micro-plasmas, semiconductors, quantum-effect structures, vacuum devices, and emerging materials with applications in bioelectronics, biomedical electronics, computation, communications, displays, microelectromechanics, imaging, micro-actuators, nanoelectronics, optoelectronics, photovoltaics, power ICs and micro-sensors. Tutorial and review papers on these subjects are also published and occasional special issues appear to present a collection of papers which treat particular areas in more depth and breadth.