中国物理B ›› 2024, Vol. 33 ›› Issue (1): 17302-17302.doi: 10.1088/1674-1056/ad01a7

• • 上一篇    下一篇

Physical mechanism of oxygen diffusion in the formation of Ga2O3 Ohmic contacts

Su-Yu Xu(徐宿雨)1, Miao Yu(于淼)1,†, Dong-Yang Yuan(袁东阳)2, Bo Peng(彭博)1, Lei Yuan(元磊)1, Yu-Ming Zhang(张玉明)1, and Ren-Xu Jia(贾仁需)1,‡   

  1. 1 Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China;
    2 The 13 th Research Institute China Electronics Technology Group Corporation, Shijiazhuang 050051, China
  • 收稿日期:2023-08-02 修回日期:2023-09-18 接受日期:2023-10-07 出版日期:2023-12-13 发布日期:2024-01-03
  • 通讯作者: Miao Yu, Ren-Xu Jia E-mail:myuxidian@163.com;rxjia@mail.xidian.edu.cn
  • 基金资助:
    Projects supported by the National Natural Science Foundation of China (Grant Nos. 61874084, 61974119, and U21A20501).

Physical mechanism of oxygen diffusion in the formation of Ga2O3 Ohmic contacts

Su-Yu Xu(徐宿雨)1, Miao Yu(于淼)1,†, Dong-Yang Yuan(袁东阳)2, Bo Peng(彭博)1, Lei Yuan(元磊)1, Yu-Ming Zhang(张玉明)1, and Ren-Xu Jia(贾仁需)1,‡   

  1. 1 Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China;
    2 The 13 th Research Institute China Electronics Technology Group Corporation, Shijiazhuang 050051, China
  • Received:2023-08-02 Revised:2023-09-18 Accepted:2023-10-07 Online:2023-12-13 Published:2024-01-03
  • Contact: Miao Yu, Ren-Xu Jia E-mail:myuxidian@163.com;rxjia@mail.xidian.edu.cn
  • Supported by:
    Projects supported by the National Natural Science Foundation of China (Grant Nos. 61874084, 61974119, and U21A20501).

摘要: The formation of low-resistance Ohmic contacts in Ga2O3 is crucial for high-performance electronic devices. Conventionally, a titanium/gold (Ti/Au) electrode is rapidly annealed to achieve Ohmic contacts, resulting in mutual diffusion of atoms at the interface. However, the specific role of diffusing elements in Ohmic contact formation remains unclear. In this work, we investigate the contribution of oxygen atom diffusion to the formation of Ohmic contacts in Ga2O3. We prepare a Ti/Au electrode on a single crystal substrate and conduct a series of electrical and structural characterizations. Using density functional theory, we construct a model of the interface and calculate the charge density, partial density of states, planar electrostatic potential energy, and IV characteristics. Our results demonstrate that the oxygen atom diffusion effectively reduces the interface barrier, leading to low-resistance Ohmic contacts in Ga2O3. These findings provide valuable insights into the underlying mechanisms of Ohmic contact formation and highlight the importance of considering the oxygen atom diffusion in the design of Ga2O3-based electronic devices.

关键词: Ga2O3, Ohmic contacts, oxygen diffusion, density functional theory

Abstract: The formation of low-resistance Ohmic contacts in Ga2O3 is crucial for high-performance electronic devices. Conventionally, a titanium/gold (Ti/Au) electrode is rapidly annealed to achieve Ohmic contacts, resulting in mutual diffusion of atoms at the interface. However, the specific role of diffusing elements in Ohmic contact formation remains unclear. In this work, we investigate the contribution of oxygen atom diffusion to the formation of Ohmic contacts in Ga2O3. We prepare a Ti/Au electrode on a single crystal substrate and conduct a series of electrical and structural characterizations. Using density functional theory, we construct a model of the interface and calculate the charge density, partial density of states, planar electrostatic potential energy, and IV characteristics. Our results demonstrate that the oxygen atom diffusion effectively reduces the interface barrier, leading to low-resistance Ohmic contacts in Ga2O3. These findings provide valuable insights into the underlying mechanisms of Ohmic contact formation and highlight the importance of considering the oxygen atom diffusion in the design of Ga2O3-based electronic devices.

Key words: Ga2O3, Ohmic contacts, oxygen diffusion, density functional theory

中图分类号:  (Other inorganic semiconductors)

  • 73.61.Le
73.40.Ns (Metal-nonmetal contacts) 66.30.J- (Diffusion of impurities ?) 71.15.Mb (Density functional theory, local density approximation, gradient and other corrections)