Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (4): 47102-047102.doi: 10.1088/1674-1056/22/4/047102

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

Influence of Schottky drain contacts on the strained AlGaN barrier layer of AlGaN/AlN/GaN heterostructure field-effect transistors

曹芝芳a, 林兆军a, 吕元杰a, 栾崇彪a, 王占国b   

  1. a School of Physics, Shandong University, Jinan 250100, China;
    b Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
  • 收稿日期:2012-06-26 修回日期:2012-08-01 出版日期:2013-03-01 发布日期:2013-03-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11174182) and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20110131110005).

Influence of Schottky drain contacts on the strained AlGaN barrier layer of AlGaN/AlN/GaN heterostructure field-effect transistors

Cao Zhi-Fang (曹芝芳)a, Lin Zhao-Jun (林兆军)a, Lü Yuan-Jie (吕元杰)a, Luan Chong-Biao (栾崇彪)a, Wang Zhan-Guo (王占国)b   

  1. a School of Physics, Shandong University, Jinan 250100, China;
    b Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
  • Received:2012-06-26 Revised:2012-08-01 Online:2013-03-01 Published:2013-03-01
  • Contact: Lin Zhao-Jun E-mail:linzj@sdu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11174182) and the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20110131110005).

摘要: Rectangular Schottky drain AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) with different gate contact areas and conventional AlGaN/AlN/GaN HFETs as control were both fabricated with same size. It was found there is a significant difference between Schottky drain AlGaN/AlN/GaN HFETs and the control group both in drain series resistance and in two-dimensional electron gas (2DEG) electron mobility in the gate-drain channel. We attribute this to the different influence of Ohmic drain contacts and Schottky drain contacts on the strained AlGaN barrier layer. For conventional AlGaN/AlN/GaN HFETs, annealing drain Ohmic contacts gives rise to a strain variation in the AlGaN barrier layer between the gate contacts and the drain contacts, and results in strong polarization Coulomb field scattering in this region. In Schottky drain AlGaN/AlN/GaN HFETs, the strain in the AlGaN barrier layer is distributed more regularly.

关键词: AlGaN/AlN/GaN HFET, Schottky drain contact, AlGaN barrier layer strain, polarization Coulomb field scattering

Abstract: Rectangular Schottky drain AlGaN/AlN/GaN heterostructure field-effect transistors (HFETs) with different gate contact areas and conventional AlGaN/AlN/GaN HFETs as control were both fabricated with same size. It was found there is a significant difference between Schottky drain AlGaN/AlN/GaN HFETs and the control group both in drain series resistance and in two-dimensional electron gas (2DEG) electron mobility in the gate-drain channel. We attribute this to the different influence of Ohmic drain contacts and Schottky drain contacts on the strained AlGaN barrier layer. For conventional AlGaN/AlN/GaN HFETs, annealing drain Ohmic contacts gives rise to a strain variation in the AlGaN barrier layer between the gate contacts and the drain contacts, and results in strong polarization Coulomb field scattering in this region. In Schottky drain AlGaN/AlN/GaN HFETs, the strain in the AlGaN barrier layer is distributed more regularly.

Key words: AlGaN/AlN/GaN HFET, Schottky drain contact, AlGaN barrier layer strain, polarization Coulomb field scattering

中图分类号:  (III-V semiconductors)

  • 71.55.Eq
72.10.-d (Theory of electronic transport; scattering mechanisms) 73.61.Ey (III-V semiconductors)