Experimental Formation and Mechanism Study for Super-High Dielectric Constant AlO/TiO Nanolaminates.

Super-high dielectric constant () AlO/TiO nanolaminates (ATO NLs) are deposited by an atomic layer deposition technique for application in next-generation electronics. Individual multilayers with uniform thicknesses are formed for the ATO NLs. With an increase in AlO content in each ATO sublayer, the shape of the Raman spectrum has a tendency to approach that of a single AlO layer.

Edge-of-chaos learning achieved by ion-electron-coupled dynamics in an ion-gating reservoir.

Physical reservoir computing has recently been attracting attention for its ability to substantially reduce the computational resources required to process time series data. However, the physical reservoirs that have been reported to date have had insufficient computational capacity, and most of them have a large volume, which makes their practical application difficult. Here, we describe the development of a Li electrolyte-based ion-gating reservoir (IGR), with ion-electron-coupled dynamics, for use in high-performance physical reservoir computing.

Stress effect on the resonance properties of single-crystal diamond cantilever resonators for microscopy applications.

Micro-cantilever beams have been widely used for surface sensing applications as well as atomic force microscope. However, surface stress appears in cantilever beams due to a variety of factors such as the absorption of molecules, temperature variations, materials imperfectness, and the fabrication process. Single-crystal diamond (SCD) has been regarded as an ideal material for cantilever sensors through the surface effect due to the outstanding mechanical rigidity and chemical inertness.

The electric double layer effect and its strong suppression at Li solid electrolyte/hydrogenated diamond interfaces.

The electric double layer (EDL) effect at solid electrolyte/electrode interfaces has been a key topic in many energy and nanoelectronics applications (e.g., all-solid-state Li batteries and memristors).

Epitaxial Combination of Two-Dimensional Hexagonal Boron Nitride with Single-Crystalline Diamond Substrate.

Hexagonal boron nitride (hBN) and diamond are promising materials for next-generation electronics and optoelectronics. However, their combination is rarely reported. In this study, we for the first time demonstrate the success to direct growth of two-dimensional (2D) hBN crystal layers on diamond substrates by metalorganic vapor phase epitaxy.

Enhancing Delta Effect at High Temperatures of Galfenol/Ti/Single-Crystal Diamond Resonators for Magnetic Sensing.

A conventional wisdom is that the sensing properties of magnetic sensors at high temperatures will be degraded due to the materials' deterioration. Here, the concept of high-temperature enhancing magnetic sensing is proposed based on the hybrid structure of SCD MEMS resonator functionalized with a high thermal-stable ferromagnetic galfenol (FeGa) film. The delta effect of the magnetostrictive FeGa thin film on Ti/SCD cantilevers is investigated by varying the operating temperature from 300 to 773 K upon external magnetic fields.

Surface morphology smoothing of a 2 inch-diameter GaN homoepitaxial layer observed by X-ray diffraction topography.

We investigated the surface morphology changes in a 2 inch-diameter, -plane, free-standing GaN wafer using X-ray diffraction topography in a grazing-incidence geometry. We observed a decrease in the peak intensity and increase in the full width at half maximum of the GaN 112Ì„4 Bragg peak after the deposition of a homoepitaxial layer on the same GaN wafer. However, the lattice plane bending angles did not change after homoepitaxial layer deposition.

High-performance visible to near-infrared photodetectors by using (Cd,Zn)Te single crystal.

The authors report on a high-performance metal-semiconductor-metal (MSM) photodetector fabricated on the CdZnTe single crystal with the photoresponse from visible to near infrared region. Benefitting from the high-quality single crystallization, an ultra-low dark current of ~10 A was obtained at a high applied voltage of 10 V, leading to a photo-to-dark-current ratio of more than 10 at 700 nm light illumination. The highest responsivity is estimated to be 1.

An Overview of High- Oxides on Hydrogenated-Diamond for Metal-Oxide-Semiconductor Capacitors and Field-Effect Transistors.

Thanks to its excellent intrinsic properties, diamond is promising for applications of high-power electronic devices, ultraviolet detectors, biosensors, high-temperature tolerant gas sensors, etc. Here, an overview of high- oxides on hydrogenated-diamond (H-diamond) for metal-oxide-semiconductor (MOS) capacitors and MOS field-effect transistors (MOSFETs) is demonstrated. Fabrication routines for the H-diamond MOS capacitors and MOSFETs, band configurations of oxide/H-diamond heterointerfaces, and electrical properties of the MOS and MOSFETs are summarized and discussed.

Magnetic Control of Magneto-Electrochemical Cell and Electric Double Layer Transistor.

A magneto-electrochemical cell and an electric double layer transistor (EDLT), each containing diluted [Bmim]FeCl solution, have been controlled by applying a magnetic field in contrast to the control of conventional field effect devices by an applied electric field. A magnetic field of several hundred mT generated by a small neodymium magnet is sufficient to operate magneto-electrochemical cells, which generate an electromotive force of 130 mV at maximum. An EDLT composed of hydrogen-terminated diamond was also operated by applying a magnetic field.

Fabrication of Hydrogenated Diamond Metal-Insulator-Semiconductor Field-Effect Transistors.

Diamond is regarded as a promising material for fabrication of high-power and high-frequency electronic devices due to its remarkable intrinsic properties, such as wide band gap energy, high carrier mobility, and high breakdown field. Meanwhile, since diamond has good biocompatibility, long-term durability, good chemical inertness, and a large electron-chemical potential window, it is a suitable candidate for the fabrication of biosensors. Here, we demonstrate the fabrication of hydrogenated diamond (H-diamond) based metal-insulator-semiconductor field-effect transistors (MISFETs).

Self-assembling diacetylene molecules on atomically flat insulators.

Single crystal sapphire and diamond surfaces are used as planar, atomically flat insulating surfaces, for the deposition of the diacetylene compound 10,12-nonacosadiynoic acid. The surface assembly is compared with results on hexagonal boron nitride (h-BN), highly oriented pyrolytic graphite (HOPG) and MoS surfaces. A perfectly flat-lying monolayer of 10,12-nonacosadiynoic acid self-assembles on h-BN like on HOPG and MoS.

Design and fabrication of high-performance diamond triple-gate field-effect transistors.

The lack of large-area single-crystal diamond wafers has led us to downscale diamond electronic devices. Here, we design and fabricate a hydrogenated diamond (H-diamond) triple-gate metal-oxide-semiconductor field-effect transistor (MOSFET) to extend device downscaling and increase device output current. The device's electrical properties are compared with those of planar-type MOSFETs, which are fabricated simultaneously on the same substrate.

P-Channel InGaN/GaN heterostructure metal-oxide-semiconductor field effect transistor based on polarization-induced two-dimensional hole gas.

The concept of p-channel InGaN/GaN heterostructure field effect transistor (FET) using a two-dimensional hole gas (2DHG) induced by polarization effect is demonstrated. The existence of 2DHG near the lower interface of InGaN/GaN heterostructure is verified by theoretical simulation and capacitance-voltage profiling. The metal-oxide-semiconductor FET (MOSFET) with Al2O3 gate dielectric shows a drain-source current density of 0.

Low on-resistance diamond field effect transistor with high-k ZrO2 as dielectric.

Although several high-k insulators have been deposited on the diamond for metal-insulator-semiconductor field effect transistors (MISFETs) fabrication, the k values and current output are still not fully satisfactory. Here, we present a high-k ZrO2 layer on the diamond for the MISFETs. The k value for ZrO2 is determined by capacitance-voltage characteristic to be 15.

Flexible ultraviolet photodetectors with broad photoresponse based on branched ZnS-ZnO heterostructure nanofilms.

The application of nanofilm networks made of branched ZnS-ZnO nanostructures as a flexible UV photodetector is demonstrated. The fabricated devices show excellent operational characteristics: tunable spectral selectivity, widerange photoresponse, fast response speed, and excellent environmental stability.

A multilevel intermediate-band solar cell by InGaN/GaN quantum dots with a strain-modulated structure.

Multiple stacked InGaN/GaN quantum dots are embedded into an InGaN p-n junction to develop multilevel intermediateband (MIB) solar cells. An IB transition is evidenced from both experiment and theoretical calculations. The MIB solar cell shows a wide photovoltaic response from the UV to the near-IR region.

Arbitrary multicolor photodetection by hetero-integrated semiconductor nanostructures.

The typical photodetectors can only detect one specific optical spectral band, such as InGaAs and graphene-PbS quantum dots for near-infrared (NIR) light detection, CdS and Si for visible light detection, and ZnO and III-nitrides for UV light detection. So far, none of the developed photodetector can achieve the multicolor detection with arbitrary spectral selectivity, high sensitivity, high speed, high signal-to-noise ratio, high stability, and simplicity (called 6S requirements). Here, we propose a universal strategy to develop multicolor photodetectors with arbitrary spectral selectivity by integrating various semiconductor nanostructures on a wide-bandgap semiconductor or an insulator substrate.

Deep-ultraviolet solar-blind photoconductivity of individual gallium oxide nanobelts.

We designed solar-blind deep-ultraviolet semiconductor photodetectors using individual Ga2O3 nanobelts. The photoconductive behavior was systematically studied. The photodetectors demonstrate high selectivity towards 250 nm light, fast response times of less than 0.

Electrical transport and high-performance photoconductivity in individual ZrS(2) nanobelts.

Individual ZrS(2)-nanobelt field-effect transistors were fabricated using a photolithography process. Temperature-dependent electrical transport revealed different electrical conductivity mechanism at different working temperature regions. ZrS(2)-nanobelt photodetectors demonstrated a high-performance visible-light photoconductivity.

Bascule nanobridges self-assembled with ZnO nanowires as double Schottky barrier UV switches.

We report the fabrication of a double Schottky barrier (DSB) device by self-assembly of nanowires (NWs). The operating principle of the device is governed by the surface depletion effects of the NWs. High DSBs were formed at the contact interface of ZnO NWs self-assembled into bascule nanobridge (NB) structures.