中国物理B ›› 2016, Vol. 25 ›› Issue (8): 88503-088503.doi: 10.1088/1674-1056/25/8/088503

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Improvement in the electrical performance and bias-stress stability of dual-active-layered silicon zinc oxide/zinc oxide thin-film transistor

Yu-Rong Liu(刘玉荣), Gao-Wei Zhao(赵高位), Pai-To Lai(黎沛涛), Ruo-He Yao(姚若河)   

  1. 1 The School of Electronic and Information Engineering, South China University of Technology, Guangzhou 510640, China;
    2 National Engineering Technology Research Center for Mobile Ultrasonic Detection, South China University of Technology, Guangzhou 510640, China;
    3 Department of Electrical and Electronic Engineering, the University of Hong Kong, Pokfulam Rd., Hong Kong, China
  • 收稿日期:2016-01-30 修回日期:2016-04-08 出版日期:2016-08-05 发布日期:2016-08-05
  • 通讯作者: Yu-Rong Liu E-mail:phlyr@scut.edu.cn
  • 基金资助:
    Projected supported by the National Natural Science Foundation of China (Grant Nos. 61076113 and 61274085), the Natural Science Foundation of Guangdong Province (Grant No. 2016A030313474), and the University Development Fund (Nanotechnology Research Institute, Grant No. 00600009) of the University of Hong Kong, China.

Improvement in the electrical performance and bias-stress stability of dual-active-layered silicon zinc oxide/zinc oxide thin-film transistor

Yu-Rong Liu(刘玉荣)1,2, Gao-Wei Zhao(赵高位)1, Pai-To Lai(黎沛涛)3, Ruo-He Yao(姚若河)1,2   

  1. 1 The School of Electronic and Information Engineering, South China University of Technology, Guangzhou 510640, China;
    2 National Engineering Technology Research Center for Mobile Ultrasonic Detection, South China University of Technology, Guangzhou 510640, China;
    3 Department of Electrical and Electronic Engineering, the University of Hong Kong, Pokfulam Rd., Hong Kong, China
  • Received:2016-01-30 Revised:2016-04-08 Online:2016-08-05 Published:2016-08-05
  • Contact: Yu-Rong Liu E-mail:phlyr@scut.edu.cn
  • Supported by:
    Projected supported by the National Natural Science Foundation of China (Grant Nos. 61076113 and 61274085), the Natural Science Foundation of Guangdong Province (Grant No. 2016A030313474), and the University Development Fund (Nanotechnology Research Institute, Grant No. 00600009) of the University of Hong Kong, China.

摘要: Si-doped zinc oxide (SZO) thin films are deposited by using a co-sputtering method, and used as the channel active layers of ZnO-based TFTs with single and dual active layer structures. The effects of silicon content on the optical transmittance of the SZO thin film and electrical properties of the SZO TFT are investigated. Moreover, the electrical performances and bias-stress stabilities of the single- and dual-active-layer TFTs are investigated and compared to reveal the effects of the Si doping and dual-active-layer structure. The average transmittances of all the SZO films are about 90% in the visible light region of 400 nm-800 nm, and the optical band gap of the SZO film gradually increases with increasing Si content. The Si-doping can effectively suppress the grain growth of ZnO, revealed by atomic force microscope analysis. Compared with that of the undoped ZnO TFT, the off-state current of the SZO TFT is reduced by more than two orders of magnitude and it is 1.5×10-12 A, and thus the on/off current ratio is increased by more than two orders of magnitude. In summary, the SZO/ZnO TFT with dual-active-layer structure exhibits a high on/off current ratio of 4.0×106 and superior stability under gate-bias and drain-bias stress.

关键词: thin film transistor (TFT), silicon-doped zinc oxide, dual-active-layer structure, bias-stress stability

Abstract: Si-doped zinc oxide (SZO) thin films are deposited by using a co-sputtering method, and used as the channel active layers of ZnO-based TFTs with single and dual active layer structures. The effects of silicon content on the optical transmittance of the SZO thin film and electrical properties of the SZO TFT are investigated. Moreover, the electrical performances and bias-stress stabilities of the single- and dual-active-layer TFTs are investigated and compared to reveal the effects of the Si doping and dual-active-layer structure. The average transmittances of all the SZO films are about 90% in the visible light region of 400 nm-800 nm, and the optical band gap of the SZO film gradually increases with increasing Si content. The Si-doping can effectively suppress the grain growth of ZnO, revealed by atomic force microscope analysis. Compared with that of the undoped ZnO TFT, the off-state current of the SZO TFT is reduced by more than two orders of magnitude and it is 1.5×10-12 A, and thus the on/off current ratio is increased by more than two orders of magnitude. In summary, the SZO/ZnO TFT with dual-active-layer structure exhibits a high on/off current ratio of 4.0×106 and superior stability under gate-bias and drain-bias stress.

Key words: thin film transistor (TFT), silicon-doped zinc oxide, dual-active-layer structure, bias-stress stability

中图分类号:  (Field effect devices)

  • 85.30.Tv
73.61.Ga (II-VI semiconductors) 72.80.Ey (III-V and II-VI semiconductors) 73.20.-r (Electron states at surfaces and interfaces)