中国物理B ›› 2015, Vol. 24 ›› Issue (8): 87306-087306.doi: 10.1088/1674-1056/24/8/087306

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

Influence of the AlGaN barrier thickness on polarization Coulomb field scattering in an AlGaN/AlN/GaN heterostructure field-effect transistor

吕元杰a, 冯志红a, 顾国栋a, 尹甲运a, 房玉龙a, 王元刚a, 谭鑫a, 周幸叶a, 林兆军b, 冀子武b, 蔡树军a   

  1. a National Key Laboratory of Application Specific Integrated Circuit (ASIC), Hebei Semiconductor Research Institute, Shijiazhuang 050051, China;
    b School of Physics, Shandong University, Jinan 250100, China
  • 收稿日期:2015-01-14 修回日期:2015-02-24 出版日期:2015-08-05 发布日期:2015-08-05
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61306113 and11174182).

Influence of the AlGaN barrier thickness on polarization Coulomb field scattering in an AlGaN/AlN/GaN heterostructure field-effect transistor

Lv Yuan-Jie (吕元杰)a, Feng Zhi-Hong (冯志红)a, Gu Guo-Dong (顾国栋)a, Yin Jia-Yun (尹甲运)a, Fang Yu-Long (房玉龙)a, Wang Yuan-Gang (王元刚)a, Tan Xin (谭鑫)a, Zhou Xing-Ye (周幸叶)a, Lin Zhao-Jun (林兆军)b, Ji Zi-Wu (冀子武)b, Cai Shu-Jun (蔡树军)a   

  1. a National Key Laboratory of Application Specific Integrated Circuit (ASIC), Hebei Semiconductor Research Institute, Shijiazhuang 050051, China;
    b School of Physics, Shandong University, Jinan 250100, China
  • Received:2015-01-14 Revised:2015-02-24 Online:2015-08-05 Published:2015-08-05
  • Contact: Feng Zhi-Hong E-mail:ga917vv@163.com
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61306113 and11174182).

摘要: In this study rectangular AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) with 22-nm and 12-nm AlGaN barrier layers are fabricated, respectively. Using the measured capacitance–voltage and current–voltage characteristics of the prepared devices with different Schottky areas, it is found that after processing the device, the polarization Coulomb field (PCF) scattering is induced and has an important influence on the two-dimensional electron gas electron mobility. Moreover, the influence of PCF scattering on the electron mobility is enhanced by reducing the AlGaN barrier thickness. This leads to the quite different variation of the electron mobility with gate bias when compared with the AlGaN barrier thickness. This mainly happens because the thinner AlGaN barrier layer suffers from a much stronger electrical field when applying a gate bias, which gives rise to a stronger converse piezoelectric effect.

关键词: AlGaN/AlN/GaN, barrier layer thickness, electron mobility, polarization Coulomb field scattering

Abstract: In this study rectangular AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) with 22-nm and 12-nm AlGaN barrier layers are fabricated, respectively. Using the measured capacitance–voltage and current–voltage characteristics of the prepared devices with different Schottky areas, it is found that after processing the device, the polarization Coulomb field (PCF) scattering is induced and has an important influence on the two-dimensional electron gas electron mobility. Moreover, the influence of PCF scattering on the electron mobility is enhanced by reducing the AlGaN barrier thickness. This leads to the quite different variation of the electron mobility with gate bias when compared with the AlGaN barrier thickness. This mainly happens because the thinner AlGaN barrier layer suffers from a much stronger electrical field when applying a gate bias, which gives rise to a stronger converse piezoelectric effect.

Key words: AlGaN/AlN/GaN, barrier layer thickness, electron mobility, polarization Coulomb field scattering

中图分类号:  (III-V semiconductors)

  • 73.61.Ey
77.22.Ej (Polarization and depolarization) 72.10.-d (Theory of electronic transport; scattering mechanisms) 73.50.Dn (Low-field transport and mobility; piezoresistance)