中国物理B ›› 2014, Vol. 23 ›› Issue (3): 37303-037303.doi: 10.1088/1674-1056/23/3/037303

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

Leakage current reduction by thermal oxidation in Ni/Au Schottky contacts on lattice-matched In0.18Al0.82N/GaN heterostructures

林芳a, 沈波a, 卢励吾a, 许福军a, 刘新宇b, 魏珂b   

  1. a State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China;
    b Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China
  • 收稿日期:2013-05-09 修回日期:2013-07-29 出版日期:2014-03-15 发布日期:2014-03-15
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60444007, 11174008, 60325413, and 10774001).

Leakage current reduction by thermal oxidation in Ni/Au Schottky contacts on lattice-matched In0.18Al0.82N/GaN heterostructures

Lin Fang (林芳)a, Shen Bo (沈波)a, Lu Li-Wu (卢励吾)a, Xu Fu-Jun (许福军)a, Liu Xin-Yu (刘新宇)b, Wei Ke (魏珂)b   

  1. a State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China;
    b Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China
  • Received:2013-05-09 Revised:2013-07-29 Online:2014-03-15 Published:2014-03-15
  • Contact: Lin Fang E-mail:linfang@pku.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 60444007, 11174008, 60325413, and 10774001).

摘要: By using temperature-dependent current–voltage, variable-frequency capacitance–voltage, and Hall measurements, the effects of the thermal oxidation on the electrical properties of Ni/Au Schottky contacts on lattice-matched In0.18Al0.82N/GaN heterostructures are investigated. Decrease of the reverse leakage current down to six orders of magnitude is observed after the thermal oxidation of the In0.18Al0.82N/GaN heterostructures at 700 ℃. It is confirmed that the reverse leakage current is dominated by the Frenkel–Poole emission, and the main origin of the leakage current is the emission of electrons from a trap state near the metal/semiconductor interface into a continuum of electronic states associated with the conductive dislocations in the InxAl1-xN barrier. It is believed that the thermal oxidation results in the formation of a thin oxide layer on the InxAl1-xN surface, which increases the electron emission barrier height.

关键词: leakage current, thermal oxidation, Frenkel–, Poole emission

Abstract: By using temperature-dependent current–voltage, variable-frequency capacitance–voltage, and Hall measurements, the effects of the thermal oxidation on the electrical properties of Ni/Au Schottky contacts on lattice-matched In0.18Al0.82N/GaN heterostructures are investigated. Decrease of the reverse leakage current down to six orders of magnitude is observed after the thermal oxidation of the In0.18Al0.82N/GaN heterostructures at 700 ℃. It is confirmed that the reverse leakage current is dominated by the Frenkel–Poole emission, and the main origin of the leakage current is the emission of electrons from a trap state near the metal/semiconductor interface into a continuum of electronic states associated with the conductive dislocations in the InxAl1-xN barrier. It is believed that the thermal oxidation results in the formation of a thin oxide layer on the InxAl1-xN surface, which increases the electron emission barrier height.

Key words: leakage current, thermal oxidation, Frenkel–Poole emission

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)