中国物理B ›› 2020, Vol. 29 ›› Issue (8): 87304-087304.doi: 10.1088/1674-1056/ab8daa

• SPECIAL TOPIC—Ultracold atom and its application in precision measurement • 上一篇    下一篇

Comparative study on characteristics of Si-based AlGaN/GaN recessed MIS-HEMTs with HfO2 and Al2O3 gate insulators

Yao-Peng Zhao(赵垚澎), Chong Wang(王冲), Xue-Feng Zheng(郑雪峰), Xiao-Hua Ma(马晓华), Kai Liu(刘凯), Ang Li(李昂), Yun-Long He(何云龙), Yue Hao(郝跃)   

  1. Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China
  • 收稿日期:2020-03-18 修回日期:2020-04-24 出版日期:2020-08-05 发布日期:2020-08-05
  • 通讯作者: Chong Wang, Chong Wang E-mail:chongw@xidian.edu.cn;xfzheng@mail.xidian.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61974111, 11690042, and 61974115), the National Pre-research Foundation of China (Grant No. 31512050402), and the Fund of Innovation Center of Radiation Application, China (Grant No. KFZC2018040202).

Comparative study on characteristics of Si-based AlGaN/GaN recessed MIS-HEMTs with HfO2 and Al2O3 gate insulators

Yao-Peng Zhao(赵垚澎), Chong Wang(王冲), Xue-Feng Zheng(郑雪峰), Xiao-Hua Ma(马晓华), Kai Liu(刘凯), Ang Li(李昂), Yun-Long He(何云龙), Yue Hao(郝跃)   

  1. Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi'an 710071, China
  • Received:2020-03-18 Revised:2020-04-24 Online:2020-08-05 Published:2020-08-05
  • Contact: Chong Wang, Chong Wang E-mail:chongw@xidian.edu.cn;xfzheng@mail.xidian.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61974111, 11690042, and 61974115), the National Pre-research Foundation of China (Grant No. 31512050402), and the Fund of Innovation Center of Radiation Application, China (Grant No. KFZC2018040202).

摘要: Two types of enhancement-mode (E-mode) AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) with different gate insulators are fabricated on Si substrates. The HfO2 gate insulator and the Al2O3 gate insulator each with a thickness of 30 nm are grown by the plasma-enhanced atomic layer deposition (PEALD). The energy band diagrams of two types of dielectric MIS-HEMTs are compared. The breakdown voltage (VBR) of HfO2 dielectric layer and Al2O3 dielectric layer are 9.4 V and 15.9 V, respectively. With the same barrier thickness, the transconductance of MIS-HEMT with HfO2 is larger. The threshold voltage (Vth) of the HfO2 and Al2O3 MIS-HEMT are 2.0 V and 2.4 V, respectively, when the barrier layer thickness is 0 nm. The C-V characteristics are in good agreement with the Vth's transfer characteristics. As the barrier layer becomes thinner, the drain current density decreases sharply. Due to the dielectric/AlGaN interface is very close to the channel, the scattering of interface states will lead the electron mobility to decrease. The current collapse and the Ron of Al2O3 MIS-HEMT are smaller at the maximum gate voltage. As Al2O3 has excellent thermal stability and chemical stability, the interface state density of Al2O3/AlGaN is less than that of HfO2/AlGaN.

关键词: AlGaN/GaN, enhancement-mode, MIS-HEMT, HfO2, Al2O3

Abstract: Two types of enhancement-mode (E-mode) AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (MIS-HEMTs) with different gate insulators are fabricated on Si substrates. The HfO2 gate insulator and the Al2O3 gate insulator each with a thickness of 30 nm are grown by the plasma-enhanced atomic layer deposition (PEALD). The energy band diagrams of two types of dielectric MIS-HEMTs are compared. The breakdown voltage (VBR) of HfO2 dielectric layer and Al2O3 dielectric layer are 9.4 V and 15.9 V, respectively. With the same barrier thickness, the transconductance of MIS-HEMT with HfO2 is larger. The threshold voltage (Vth) of the HfO2 and Al2O3 MIS-HEMT are 2.0 V and 2.4 V, respectively, when the barrier layer thickness is 0 nm. The C-V characteristics are in good agreement with the Vth's transfer characteristics. As the barrier layer becomes thinner, the drain current density decreases sharply. Due to the dielectric/AlGaN interface is very close to the channel, the scattering of interface states will lead the electron mobility to decrease. The current collapse and the Ron of Al2O3 MIS-HEMT are smaller at the maximum gate voltage. As Al2O3 has excellent thermal stability and chemical stability, the interface state density of Al2O3/AlGaN is less than that of HfO2/AlGaN.

Key words: AlGaN/GaN, enhancement-mode, MIS-HEMT, HfO2, Al2O3

中图分类号:  (III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions)

  • 73.40.Kp
73.40.Rw (Metal-insulator-metal structures) 73.40.Qv (Metal-insulator-semiconductor structures (including semiconductor-to-insulator)) 73.61.Ey (III-V semiconductors)