Yue, Hangyu; Zhu, Zixuan; Chen, Xiang; Zhao, Feiyang; Wang, Hui; Tian, Li; Zhu, Hao; Li, Qiliang

IEEE TRANSACTIONS ON ELECTRON DEVICES

2025, 11,

Yue, Hangyu; Zhu, Zixuan; Chen, Xiang; Zhao, Feiyang; Wang, Hui; Tian, Li; Zhu, Hao; Li, Qiliang

This work presents the design and characterization of high-performance hydrogen-terminated diamond (H-diamond) MOSFETs utilizing Al-doped HfO2 (HAO) as the gate dielectric. A 15-nm HAO layer with a Hf-to-Al ratio of 16:1 was deposited at 250 C-degrees on a single-crystal diamond substrate, achieving a dielectric constant of 20.2 and a gate oxide capacitance (C-ox) of 1.19 mu F/cm(2). Two MOSFETs were fabricated and evaluated: one with a gate length of 2.8 mu mand a channel length of 13 mu mand another with a gate length of 2.4 mu mand a channel length of 10 mu m. The devices exhibit a high breakdown electric field of 14.33 MV/cmand a low gate leakage current density (J(G)) of 4.57 x 10(7) A/cm(2)at V-GS=-5 V, indicating ultralow gate leakage during operation. The output characteristics show a high ON/OFF switching ratio of approximately 10(8) across a 3.5-V gate voltage swing, making these devices attractive for practical applications.