中国物理B ›› 2015, Vol. 24 ›› Issue (11): 117307-117307.doi: 10.1088/1674-1056/24/11/117307

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

AlGaN/GaN high electron mobility transistorwith Al2O3+BCB passivation

张昇a b, 魏珂b, 余乐a b, 刘果果b, 黄森b, 王鑫华b, 庞磊b, 郑英奎b, 李艳奎b, 马晓华a, 孙兵b, 刘新宇b   

  1. a School of Advanced Materials and Nanotechnology, Key Laboratory of Wide Bandgap Semiconductor Materials and Devices, Xidian University, Xi’an 710071, China;
    b Microwave Device and IC Department, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China
  • 收稿日期:2015-06-08 修回日期:2015-07-23 出版日期:2015-11-05 发布日期:2015-11-05
  • 通讯作者: Wei Ke, Ma Xiao-Hua E-mail:weike@ime.ac.cn;xhma@xidian.edu.cn

AlGaN/GaN high electron mobility transistorwith Al2O3+BCB passivation

Zhang Sheng (张昇)a b, Wei Ke (魏珂)b, Yu Le (余乐)a b, Liu Guo-Guo (刘果果)b, Huang Sen (黄森)b, Wang Xin-Hua (王鑫华)b, Pang Lei (庞磊)b, Zheng Ying-Kui (郑英奎)b, Li Yan-Kui (李艳奎)b, Ma Xiao-Hua (马晓华)a, Sun Bing (孙兵)b, Liu Xin-Yu (刘新宇)b   

  1. a School of Advanced Materials and Nanotechnology, Key Laboratory of Wide Bandgap Semiconductor Materials and Devices, Xidian University, Xi’an 710071, China;
    b Microwave Device and IC Department, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China
  • Received:2015-06-08 Revised:2015-07-23 Online:2015-11-05 Published:2015-11-05
  • Contact: Wei Ke, Ma Xiao-Hua E-mail:weike@ime.ac.cn;xhma@xidian.edu.cn

摘要:

In this paper, Al2O3 ultrathin film used as the surface passivation layer for AlGaN/GaN high electron mobility transistor (HEMT) is deposited by thermal atomic layer deposition (ALD), thereby avoiding plasma-induced damage and erosion to the surface. A comparison is made between the surface passivation in this paper and the conventional plasma enhanced chemical vapor deposition (PECVD) SiN passivation. A remarkable reduction of the gate leakage current and a significant increase in small signal radio frequency (RF) performance are achieved after applying Al2O3+BCB passivation. For the Al2O3+BCB passivated device with a 0.7 μ gate, the value of fmax reaches up to 100 GHz, but it decreases to 40 GHz for SiN HEMT. The fmax/ft ratio (≥ 4) is also improved after Al2O3+BCB passivation. The capacitance-voltage (C-V) measurement demonstrates that Al2O3+BCB HEMT shows quite less density of trap states (on the order of magnitude of 1010 cm-2) than that obtained at commonly studied SiN HEMT.

关键词: AlGaN/GaN HEMT, Al2O3, BCB, passivation

Abstract:

In this paper, Al2O3 ultrathin film used as the surface passivation layer for AlGaN/GaN high electron mobility transistor (HEMT) is deposited by thermal atomic layer deposition (ALD), thereby avoiding plasma-induced damage and erosion to the surface. A comparison is made between the surface passivation in this paper and the conventional plasma enhanced chemical vapor deposition (PECVD) SiN passivation. A remarkable reduction of the gate leakage current and a significant increase in small signal radio frequency (RF) performance are achieved after applying Al2O3+BCB passivation. For the Al2O3+BCB passivated device with a 0.7 μ gate, the value of fmax reaches up to 100 GHz, but it decreases to 40 GHz for SiN HEMT. The fmax/ft ratio (≥ 4) is also improved after Al2O3+BCB passivation. The capacitance-voltage (C-V) measurement demonstrates that Al2O3+BCB HEMT shows quite less density of trap states (on the order of magnitude of 1010 cm-2) than that obtained at commonly studied SiN HEMT.

Key words: AlGaN/GaN HEMT, Al2O3, BCB, passivation

中图分类号:  (Metal-nonmetal contacts)

  • 73.40.Ns
73.61.Ey (III-V semiconductors) 73.20.-r (Electron states at surfaces and interfaces)