Enhanced performances of ZnO-TFT by improving surface properties of channel layer

被引：62

作者：

Zhang, Liang ^{[2
]}

Zhang, Hao ^{[1
]}

Bai, Yu ^{[2
]}

Ma, Jun Wei ^{[2
]}

Cao, Jin ^{[1
]}

Jiang, XueYin ^{[2
]}

Zhang, Zhi Lin ^{[1
,2
]}

机构：

[1] Shanghai Univ, Key Lab Adv Display & Syst Applicat, Minist Educ, Shanghai 200072, Peoples R China

[2] Shanghai Univ, Dept Mat Sci, Shanghai 200072, Peoples R China

来源：

SOLID STATE COMMUNICATIONS | 2008年 / 146卷 / 9-10期

基金：

中国国家自然科学基金;

关键词：

thin film transistor; ZnO; rf sputtering; surface morphology;

D O I：

10.1016/j.ssc.2008.03.036

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

Top-contact thin film transistors with ZnO as the channel layer and thermally grown SiO2 as the gate dielectric were fabricated by using rf sputtering. The performances of ZnO-TFTs with different thicknesses of the active layer were investigated and the optimized condition was obtained. With the active layer thickness from 25 to 70 nm, the leakage current of devices increased from 10(-10) to 10(-8) A, and the on/off ratio decreased from 1.2 x 10(7) to 2 x 10(4). Atomic force microscope research indicated that with the thickness increased, the surface morphology of the active layer improved noticeably at first and then deteriorated. The 25-nm-thick ZnO TFT had the best surface morphology, and showed the best performance with a field effect mobility of 5.1 cm(2)/V S, on/off ratio of 1.2 x 10(7) and threshold voltage of 20 V. This indicates that the surface properties of the channel layer have crucial affects on the performances of ZnO-TFTs. (C) 2008 Elsevier Ltd. All rights reserved.

引用

页码：387 / 390

页数：4