›› 2014, Vol. 23 ›› Issue (9): 97307-097307.doi: 10.1088/1674-1056/23/9/097307

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

Schottky forward current transport mechanisms in AlGaN/GaN HEMTs over a wide temperature range

武玫a b, 郑大勇c, 王媛b, 陈伟伟b, 张凯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 for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China;
    c The Fifth Electronics Research Institute of Ministry of Industry and Information Technology, Guangzhou 510610, China
  • 收稿日期:2014-03-18 修回日期:2014-04-08 出版日期:2014-09-15 发布日期:2014-09-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 61334002) and the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory of China (Grant No. ZHD201206).

Schottky forward current transport mechanisms in AlGaN/GaN HEMTs over a wide temperature range

Wu Mei (武玫)a b, Zheng Da-Yong (郑大勇)c, Wang Yuan (王媛)b, Chen Wei-Wei (陈伟伟)b, Zhang Kai (张凯)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 for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China;
    c The Fifth Electronics Research Institute of Ministry of Industry and Information Technology, Guangzhou 510610, China
  • Received:2014-03-18 Revised:2014-04-08 Online:2014-09-15 Published:2014-09-15
  • Contact: Hao Yue E-mail:yhao@xidian.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 61334002) and the Opening Project of Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory of China (Grant No. ZHD201206).

摘要: The behavior of Schottky contacts in AlGaN/GaN high electron mobility transistors (HEMTs) is investigated by temperature-dependent current-voltage (T-I-V) measurements from 300 K to 473 K. The ideality factor and barrier height determined based on the thermionic emission (TE) theory are found to be strong functions of temperature, while present a great deviation from the theoretical value, which can be expounded by the barrier height inhomogeneities. In order to determine the forward current transport mechanisms, the experimental data are analyzed using numerical fitting method, considering the temperature-dependent series resistance. It is observed that the current flow at room temperature can be attributed to the tunneling mechanism, while thermionic emission current gains a growing proportion with an increase in temperature. Finally, the effective barrier height is derived based on the extracted thermionic emission component, and an evaluation of the density of dislocations is made from the I-V characteristics, giving a value of 1.49×107 cm-2.

关键词: AlGaN/GaN HEMTs, Schottky contacts, forward current transport mechanism, temperature dependence

Abstract: The behavior of Schottky contacts in AlGaN/GaN high electron mobility transistors (HEMTs) is investigated by temperature-dependent current-voltage (T-I-V) measurements from 300 K to 473 K. The ideality factor and barrier height determined based on the thermionic emission (TE) theory are found to be strong functions of temperature, while present a great deviation from the theoretical value, which can be expounded by the barrier height inhomogeneities. In order to determine the forward current transport mechanisms, the experimental data are analyzed using numerical fitting method, considering the temperature-dependent series resistance. It is observed that the current flow at room temperature can be attributed to the tunneling mechanism, while thermionic emission current gains a growing proportion with an increase in temperature. Finally, the effective barrier height is derived based on the extracted thermionic emission component, and an evaluation of the density of dislocations is made from the I-V characteristics, giving a value of 1.49×107 cm-2.

Key words: AlGaN/GaN HEMTs, Schottky contacts, forward current transport mechanism, temperature dependence

中图分类号:  (III-V semiconductors)

  • 73.61.Ey
07.20.Dt (Thermometers) 85.30.Hi (Surface barrier, boundary, and point contact devices)