Journal of Inorganic Materials ›› 2018, Vol. 33 ›› Issue (9): 976-980.doi: 10.15541/jim20170528

• Orginal Article • Previous Articles     Next Articles

Ga2O3 MOSFET Device with Al2O3 Gate Dielectric

Yuan-Jie LV(), Xu-Bo SONG, Ze-Zhao HE, Xin TAN, Xing-Ye ZHOU, Yuan-Gang WANG, Guo-Dong GU, Zhi-Hong FENG()   

  1. National Key Laboratory of ASIC, Hebei Semiconductor Research Institute, Shijiazhuang 050051, China
  • Received:2017-11-09 Revised:2018-01-04 Online:2018-09-20 Published:2018-08-14
  • About author:LV Yuan-Jie. E-mail: yuanjielv@163.com
  • Supported by:
    National Natural Science Foundation of China (61674130, 61604137)

Abstract:

n-typed β-Ga2O3 was homoepitaxially grown by metal organic chemical vapor deposition (MOCVD) on a Fe-doped semi-insulating (010) Ga2O3 substrate. The structure consisted of a 600 nm undoped (UID) Ga2O3 buffer layer and 200 nm Si-doped channel layer. High-temperature Ohmic alloy experiments were taken on two kinds of n-typed β-Ga2O3 with Si donor concentrations of 3.0×1017 and 1.0×1018 cm-3. It’s hard to realize good Ohmic contact on the β-Ga2O3 epitaxial layer with donor concentrations of 3.0×1017 cm-3. The lowest Ohmic value of 9.8 Ω•mm was obtained on the substrate with donor concentrations of 1.0×1018 cm-3. Metal-oxide-semiconductor field-effect transistor (MOSFET) was fabricated based on homoepitaxial β-Ga2O3 film with donor concentrations of 1.0×1018 cm-3, in which Al2O3 grown by atomic layer deposition (ALD) was used as gate dielectric. The drain saturation current of the fabricated device reached 108 mA/mm at Vgs of 2 V, and a high peak transconductance of 17 mS/mm was obtained. Due to poor gate leakage, the three-terminal off-state breakdown voltage was just 23 V at Vgs = -12 V. The breakdown characteristics can be improved by introducing HfO2 with high dielectric constant or Al2O3/HfO2 composite structure.

Key words: Ga2O3, MOSFET, drain saturation current, gate leakage

CLC Number: 

  • TQ174