Normally-OFF Two-Dimensional Hole Gas Diamond MOSFETs Through Nitrogen-Ion Implantation
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2019-05-15 |
| Journal | IEEE Electron Device Letters |
| Authors | Nobutaka Oi, Takuya Kudo, Masafumi Inaba, S. Okubo, Shinobu Onoda |
| Institutions | Waseda University, National Institutes for Quantum Science and Technology |
| Citations | 50 |
Abstract
Section titled āAbstractāDiamond is a promising material for power applications owing to its excellent physical properties. Two-dimensional hole gas (2DHG) diamond metal-oxide- semiconductor field-effect transistors (MOSFETs) with hydrogen-terminated (C-H) channel have high current densities and high breakdown fields but often show normally-ON operation. From the viewpoint of safety, normally-OFF operation is required for power applications. In this letter, we used ion implantation to form a shallow and thin nitrogen-doped layer below the C-H channel region, which realized normally-OFF operation. Nitrogen-ion implanted length is fixed at 5 or 10 Ī¼m. Nitrogen is a deep donor (1.7 eV) and the nitrogen-doped layer prevents hole accumulation near the surface. The threshold voltage was as high as -2.5 V and no obvious dependence on the threshold voltage of nitrogenion implanted length is observed. The breakdown field was 2.7 MV/cm at room temperature. Of 64 devices with a common gate length, 75% showed normally-OFF operation. We confirmed the threshold voltage shift by a thin and shallow nitrogen-doped layer formed by ion implantation.
Tech Support
Section titled āTech SupportāOriginal Source
Section titled āOriginal SourceāReferences
Section titled āReferencesā- 2012 - Refractory two-dimensional hole gas on hydrogenated diamond surface [Crossref]