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A novel method to fabricate the oxidized silicon-terminated (C–Si–O) diamond metal-oxide-semi- conductor field-effect transistors (MOSFETs) by replacing the retained SiO2 masks with an atomic layer deposition (ALD)-Al2O3 film as the main gate insulator was proposed for the first time. Compositional analysis across the SiO2 masks and on the air-exposed C–Si–O (111) diamond surface has been carried out by utilizing secondary ion mass spectroscopy (SIMS) and Auger electron spectroscopy (AES) techniques, respectively. Furthermore, we revealed that, under selectively epitaxial growth of diamond through a SiO2 mask, a carbon-rich film was formed on SiO2 and C–Si bonding was realized at the SiO2/(111) diamond interface. The fabricated device with a source and drain distance (${L}_{SD}$) of $3 \,\mu \text{m}$ exhibits a distinct threshold voltage (${V}_{TH}$) of −5.6 V and a maximum drain current density (${I}_{D\_{}{MAX}}$) up to −311 mA/mm, which is a record value among normally-off single-crystalline diamond MOSFETs to date. In the case of having ALD-Al2O3 as the main gate insulator, normally-off operation of the C–Si–O diamond MOSFETs has a stark contrast with the typically normally-on performance of the hydrogen-terminated (C–H) diamond MOSFETs, which is mainly due to the smaller negative electron affinity of C–Si–O diamond compared with that of C–H diamond. These results indicate that the proposed C–Si–O (111) diamond MOSFETs with excellent normally-off operation and large drain current density are promising to fulfill the requirements of fail-safe and current drive capabilities in power device applications. [ABSTRACT FROM AUTHOR]

We propose a novel method for extracting the electromagnetic parameters (complex permittivity and permeability) of magnetic thin-film materials. The method extracts electromagnetic parameters of the magnetic thin films from effective electromagnetic parameters by using the supported vector machine (SVM). We validated the method in the frequency range of 1-8 GHz. The results show that the errors for both [epsilon]' and [mu]' are less than 0.5%, and the errors of both tan [[delta].sub.[epsilon]] and tan [[delta].sub.[mu]] are less than 0.001. Index Terms--Complex permeability, complex permittivity, microwave measurement, support vector machine (SVM).

In this article, the normally- OFF oxidized Si-terminated (C–Si) diamond metal–oxide–semiconductor field-effect transistors (MOSFETs) with as-deposited 0.5-nm silicon on diamond annealed at high temperature as the subsurface p-channel were presented for the first time. A novel method utilizing both a metal mask to realize the regrown heavily boron-doped (001) diamond layer first (p+-diamond-first) and a molecular beam deposition (MBD) method to procure atomic-scale silicon deposition was achieved. Scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDS) element mapping results suggest that the C–Si diamond/Al2O3 interface is quite continuous and atomically flat. A remarkably high threshold voltage (${V}_{\text{TH}}$) of −10 V and a maximum drain current density (${I}_{D\_{}{\text{MAX}}}$) of −156 mA/mm are simultaneously achieved in the fabricated devices. The devices with different source and drain (S/D) distances ($L_{\text{SD}}$) deliver robust ${V}_{\text{TH}}$ results and feature low OFF-state S/D leakage current $\vert {I}_{\text{leakage}}\vert $ of ~ $6\times10$ −6 mA/mm at ${V}_{\text{GS}}$ = 0 V. The extracted field-effect mobility is as high as 127 cm2 $\cdot \text{V}$ −1 $\cdot \text{s}$ −1 and the interface state density is as low as $4.35\times10$ 12 eV−1 $\cdot $ cm−2. These competitive results reveal that this first attempt of employing the combination of p+-diamond-first and MBD approaches promotes the integration of the advanced silicon manufacturing process with wide bandgap diamond material for power applications. [ABSTRACT FROM AUTHOR]