中国物理B ›› 2015, Vol. 24 ›› Issue (11): 117305-117305.doi: 10.1088/1674-1056/24/11/117305

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

Trap states induced by reactive ion etching in AlGaN/GaN high-electron-mobility transistors

罗俊a, 赵胜雷a, 宓珉瀚a, 侯斌b, 杨晓蕾b, 张进成a, 马晓华a b, 郝跃a   

  1. a Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi’an 710071, China;
    b School of Advanced Materials and Nanotechnology, Xidian University, Xi’an 710071, China
  • 收稿日期:2015-06-11 修回日期:2015-07-09 出版日期:2015-11-05 发布日期:2015-11-05
  • 通讯作者: Hao Yue E-mail:yhao@xidian.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61334002 and 61106106).

Trap states induced by reactive ion etching in AlGaN/GaN high-electron-mobility transistors

Luo Jun (罗俊)a, Zhao Sheng-Lei (赵胜雷)a, Mi Min-Han (宓珉瀚)a, Hou Bin (侯斌)b, Yang Xiao-Lei (杨晓蕾)b, Zhang Jin-Cheng (张进成)a, Ma Xiao-Hua (马晓华)a b, Hao Yue (郝跃)a   

  1. a Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi’an 710071, China;
    b School of Advanced Materials and Nanotechnology, Xidian University, Xi’an 710071, China
  • Received:2015-06-11 Revised:2015-07-09 Online:2015-11-05 Published:2015-11-05
  • Contact: Hao Yue E-mail:yhao@xidian.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61334002 and 61106106).

摘要: Frequency-dependent conductance measurements were carried out to investigate the trap states induced by reactive ion etching in AlGaN/GaN high-electron-mobility transistors (HEMTs) quantitatively. For the non-recessed HEMT, the trap state density decreases from 2.48×1013 cm-2·eV-1 at an energy of 0.29 eV to 2.79×1012 cm-2·eV-1 at ET= 0.33 eV. In contrast, the trap state density of 2.38×1013-1.10×1014 cm-2·eV-1 is located at ET in a range of 0.30-0.33 eV for the recessed HEMT. Thus, lots of trap states with shallow energy levels are induced by the gate recess etching. The induced shallow trap states can be changed into deep trap states by 350 ℃ annealing process. As a result, there are two different types of trap sates, fast and slow, in the annealed HEMT. The parameters of the annealed HEMT are ET= 0.29-0.31 eV and DT = 8.16×1012-5.58×1013 cm-2·eV-1 for the fast trap states, and ET= 0.37-0.45 eV and DT = 1.84×1013-8.50×1013 cm-2·eV-1 for the slow trap states. The gate leakage currents are changed by the etching and following annealing process, and this change can be explained by the analysis of the trap states.

关键词: AlGaN/GaN high-electron mobility transistors (HEMTs), annealing, reactive ion etching, trap states

Abstract: Frequency-dependent conductance measurements were carried out to investigate the trap states induced by reactive ion etching in AlGaN/GaN high-electron-mobility transistors (HEMTs) quantitatively. For the non-recessed HEMT, the trap state density decreases from 2.48×1013 cm-2·eV-1 at an energy of 0.29 eV to 2.79×1012 cm-2·eV-1 at ET= 0.33 eV. In contrast, the trap state density of 2.38×1013-1.10×1014 cm-2·eV-1 is located at ET in a range of 0.30-0.33 eV for the recessed HEMT. Thus, lots of trap states with shallow energy levels are induced by the gate recess etching. The induced shallow trap states can be changed into deep trap states by 350 ℃ annealing process. As a result, there are two different types of trap sates, fast and slow, in the annealed HEMT. The parameters of the annealed HEMT are ET= 0.29-0.31 eV and DT = 8.16×1012-5.58×1013 cm-2·eV-1 for the fast trap states, and ET= 0.37-0.45 eV and DT = 1.84×1013-8.50×1013 cm-2·eV-1 for the slow trap states. The gate leakage currents are changed by the etching and following annealing process, and this change can be explained by the analysis of the trap states.

Key words: AlGaN/GaN high-electron mobility transistors (HEMTs), annealing, reactive ion etching, trap states

中图分类号:  (III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions)

  • 73.40.Kp
73.61.Ey (III-V semiconductors) 78.30.Fs (III-V and II-VI semiconductors)