中国物理B ›› 2015, Vol. 24 ›› Issue (1): 17303-017303.doi: 10.1088/1674-1056/24/1/017303

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Degradation mechanism of enhancement-mode AlGaN/GaN HEMTs using fluorine ion implantation under the on-state gate overdrive stress

孙伟伟a b, 郑雪峰a b, 范爽a b, 王冲a b, 杜鸣a b, 张凯a b, 陈伟伟b, 曹艳荣b, 毛维a b, 马晓华b, 张进成a b, 郝跃a b   

  1. a School of Microelectronics, Xidian University, Xi'an 710071, China;
    b Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, Xidian University, Xi'an 710071, China
  • 收稿日期:2014-06-04 修回日期:2014-07-29 出版日期:2015-01-05 发布日期:2015-01-05
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61334002, 61106106, and 61474091), the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory (Grant No. ZHD201206), the New Experiment Development Funds for Xidian University, China (Grant No. SY1213), and the Scientific Research Foundation for the Returned Overseas Chinese Scholars.

Degradation mechanism of enhancement-mode AlGaN/GaN HEMTs using fluorine ion implantation under the on-state gate overdrive stress

Sun Wei-Wei (孙伟伟)a b, Zheng Xue-Feng (郑雪峰)a b, Fan Shuang (范爽)a b, Wang Chong (王冲)a b, Du Ming (杜鸣)a b, Zhang Kai (张凯)a b, Chen Wei-Wei (陈伟伟)b, Cao Yan-Rong (曹艳荣)b, Mao Wei (毛维)a b, Ma Xiao-Hua (马晓华)b, Zhang Jin-Cheng (张进成)a b, Hao Yue (郝跃)a b   

  1. a School of Microelectronics, Xidian University, Xi'an 710071, China;
    b Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, Xidian University, Xi'an 710071, China
  • Received:2014-06-04 Revised:2014-07-29 Online:2015-01-05 Published:2015-01-05
  • Contact: Zheng Xue-Feng E-mail:xfzheng@mail.xidian.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61334002, 61106106, and 61474091), the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory (Grant No. ZHD201206), the New Experiment Development Funds for Xidian University, China (Grant No. SY1213), and the Scientific Research Foundation for the Returned Overseas Chinese Scholars.

摘要: The degradation mechanism of enhancement-mode AlGaN/GaN high electron mobility transistors (HEMTs) fabricated by fluorine plasma ion implantation technology is one major concern of HEMT's reliability. It is observed that the threshold voltage shows a significant negative shift during the typical long-term on-state gate overdrive stress. The degradation does not originate from the presence of as-grown traps in the AlGaN barrier layer or the generated traps during fluorine ion implantation process. By comparing the relationships between the shift of threshold voltage and the cumulative injected electrons under different stress conditions, a good agreement is observed. It provides direct experimental evidence to support the impact ionization physical model, in which the degradation of E-mode HEMTs under gate overdrive stress can be explained by the ionization of fluorine ions in the AlGaN barrier layer by electrons injected from 2DEG channel. Furthermore, our results show that there are few new traps generated in the AlGaN barrier layer during the gate overdrive stress, and the ionized fluorine ions cannot recapture the electrons.

关键词: E-mode HEMTs, gate overdrive, electron injection, impact ionization

Abstract: The degradation mechanism of enhancement-mode AlGaN/GaN high electron mobility transistors (HEMTs) fabricated by fluorine plasma ion implantation technology is one major concern of HEMT's reliability. It is observed that the threshold voltage shows a significant negative shift during the typical long-term on-state gate overdrive stress. The degradation does not originate from the presence of as-grown traps in the AlGaN barrier layer or the generated traps during fluorine ion implantation process. By comparing the relationships between the shift of threshold voltage and the cumulative injected electrons under different stress conditions, a good agreement is observed. It provides direct experimental evidence to support the impact ionization physical model, in which the degradation of E-mode HEMTs under gate overdrive stress can be explained by the ionization of fluorine ions in the AlGaN barrier layer by electrons injected from 2DEG channel. Furthermore, our results show that there are few new traps generated in the AlGaN barrier layer during the gate overdrive stress, and the ionized fluorine ions cannot recapture the electrons.

Key words: E-mode HEMTs, gate overdrive, electron injection, impact ionization

中图分类号:  (III-V semiconductors)

  • 73.61.Ey
85.40.Ry (Impurity doping, diffusion and ion implantation technology) 78.30.Fs (III-V and II-VI semiconductors)