HfAlOx/Al2O3 Bilayer Dielectrics for a Field Effect Transistor on a Hydrogen-Terminated Diamond

Minghui Zhang; Fang Lin; Wei Wang; Feng Wen; Genqiang Chen; Shi He; Yanfeng Wang; Shuwei Fan; Renan Bu; Hongxing Wang

doi:10.3390/ma15020446

HfAlO_x/Al₂O₃ Bilayer Dielectrics for a Field Effect Transistor on a Hydrogen-Terminated Diamond

Materials (Basel). 2022 Jan 7;15(2):446. doi: 10.3390/ma15020446.

Authors

Minghui Zhang^{1

2}, Fang Lin^{1

2}, Wei Wang^{1

2}, Feng Wen^{1

2}, Genqiang Chen^{1

2}, Shi He^{1

2}, Yanfeng Wang^{1

2}, Shuwei Fan^{1

2}, Renan Bu^{1

2}, Hongxing Wang^{1

2}

Affiliations

¹ Key Lab for Physical Electronics and Devices, Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China.
² Institute of Wide Band Gap Semiconductors, School of Electronics and Information Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

Abstract

In this work, a hydrogen-terminated (H-terminated) diamond field effect transistor (FET) with HfAlO_x/Al₂O₃ bilayer dielectrics is fabricated and characterized. The HfAlO_x/Al₂O₃ bilayer dielectrics are deposited by the atomic layer deposition (ALD) technique, which can protect the H-terminated diamond two-dimensional hole gas (2DHG) channel. The device demonstrates normally-on characteristics, whose threshold voltage (V_TH) is 8.3 V. The maximum drain source current density (I_DSmax), transconductance (G_m), capacitance (C_OX) and carrier density (ρ) are -6.3 mA/mm, 0.73 mS/mm, 0.22 μF/cm² and 1.53 × 10¹³ cm^-2, respectively.

Keywords: HfAlOx; field effect transistor; hydrogen-terminated diamond.

Abstract

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