High- ${k}$ HfO₂ has been widely adopted in Si based MOSFETs as gate dielectric for the superior control over gate leakage and channel electrostatics. However, in AlGaN/GaN HEMTs, the additional interface issue as well as high oxygen transparency of HfO₂ has hindered its practical applications. In this work, high- ${k}~\text{Y}_{2}\text{O}_{3}$ with ultra-low oxygen permeability and high thermodynamic robustness has been introduced as the interfacial layer between HfO₂/GaN for the interface engineering. It has been demonstrated that, the HfO₂/Y₂O₃ gate dielectric stacks have obtained the GaN MIS-HEMT an ultra-small subthreshold swing of ~70 mV/decade, an extremely low gate leakage of ~10⁻¹² A/mm, and a desirable dielectric/semiconductor interface quality with interface state density in level of ~10¹² cm⁻²eV⁻¹. Meanwhile, a maximum drain current of 600mA/mm has been achieved together with an on-state resistance ( ${R} _{\mathrm{ on}}$ ) of 10.7 ${\Omega }\cdot $ mm and a specific ${R} _{\mathrm{ on}}$ of 2.62 $\text{m}{\Omega }\cdot $ cm².

中文翻译：

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基于高 k HfO2 的 AlGaN/GaN MIS-HEMT，具有 Y2O3 界面层，可实现高栅极可控性和界面质量

高的- ${k}$ HfO ₂已广泛用于 Si 基 MOSFET 作为栅极电介质，用于对栅极泄漏和沟道静电进行卓越控制。然而，在 AlGaN/GaN HEMT 中，额外的界面问题以及 HfO _{2 的}高氧透明度阻碍了其实际应用。在这项工作中，高 ${k}~\text{Y}_{2}\text{O}_{3}$ 已引入具有超低氧渗透性和高热力学稳健性的 HfO ₂ /GaN之间的界面层，用于界面工程。已经证明，HfO ₂ /Y ₂ O ₃栅极电介质叠层获得了 GaN MIS-HEMT，超小亚阈值摆幅约为 70 mV/decade，极低的栅极泄漏约为 10 ^-12 A/mm ，以及具有~10 ¹² cm ^-2 eV ^-1水平的界面态密度的理想介电/半导体界面质量。同时，最大漏极电流达到 600mA/mm，同时具有导通电阻（ ${R} _{\mathrm{ on}}$ ) 的 10.7 ${\Omega }\cdot $ mm 和一个特定的 ${R} _{\mathrm{ on}}$ 共 2.62 $\text{m}{\Omega }\cdot $ 厘米²。