We proposed a vertical enhancement-mode (E-mode) trench MOSFET based on an all-oxide n+-ZnO/p-Cu2O/n--Ga2O3 heterojunction, using p-Cu2O as the p-body layer to address the p-type doping bottleneck of β-Ga2O3. Unlike conventional inversion-channel MOSFETs that rely on minority carrier inversion to form a conductive channel, the β-Ga2O3 heterojunction MOSFETs operate via a gate-controlled barrier-modulated electron transport mechanism, in which gate bias modulates the heterojunction barrier height to control electron injection. The devices exhibit a threshold voltage (Vth) of 7 V, a Ion/Ioff of 106, a high breakdown voltage (BV) of 2000 V, and a specific on-resistance (Ron,sp) of 2.93 Ω•cm2. This work may provide a novel architecture for high-performance vertical Ga2O3 power MOSFETs.

The environmental persistence, bioaccumulation, and carcinogenicity of 4-Nitrotoluene (4-NT) demand rapid, sensitive, and selective detection strategies. We report a dual-mode sensing platform utilizing a disposable screen-printed electrode (SPCE) modified with Cu2Te/Au@rGO-AG, serving as a dual electrocatalyst for electrochemical sensing, alongside a colorimetric assay that leverages its intrinsic nanozyme activity. Structural, elemental, and morphological characterization, as confirmed by XRD, XPS, FTIR, and FESEM, demonstrated the successful integration of the composite components. The electrochemical measurements demonstrated an exceptional detection limit of 7.9 nM, with a linear range of 0.029-521.80 mu M. In parallel, colorimetric detection attained an LOD of 28.0 nM, exhibiting excellent selectivity and sensitivity. This dual strategy, integrating nanocatalyst and nanozyme functionalities, highlights Cu2Te/Au@rGO-AG as a promising real-world probe for environmental monitoring of 4-NT with high accuracy and versatility.

GaN-on-GaN high electron mobility transistors (HEMTs) have emerged as strong candidates for 5G and 6G FR3 radio-frequency (RF) front-end modules due to their high thermal stability and reliability. The RF characteristics of semi-insulating (S.I.) GaN substrates are critical for minimizing RF signal attenuation during propagation. Iron (Fe) is commonly adopted as an acceptor dopant in GaN substrates to compensate residual donors and achieve high resistivity. In this work, the DC, RF, and large-signal characteristics of AlGaN/AlN/GaN HEMTs fabricated on manganese (Mn)-doped GaN substrates are systematically demonstrated and investigated. Under comparable substrate doping concentrations, the Mn-doped GaN substrate exhibits a resistivity approximately two orders of magnitude higher than that of the Fe-doped substrate. Based on screw and edge dislocation densities extracted from high-resolution X-ray diffraction measurements, the Mn-doped substrate shows a lower screw dislocation density but a higher edge dislocation density compared with the Fe-doped substrate. Consequently, HEMTs fabricated on Mn-doped GaN substrates achieve a 0.1 dB/mm reduction in insertion loss and a 3.7 dB improvement in output third-order intercept point (OIP3), which are advantageous for reducing RF power amplifier signal loss and improving linearity.

This paper discusses a comprehensive reliability evaluation of a 1200-V 4H-SiC planar MOSFET fabricated in-house for research purposes, subjected to Unclamped Inductive Switching (UIS) stress under a wide temperature range from 25 degrees C to 175 degrees C. Avalanche current, breakdown voltage, and avalanche energy were recorded in a systematic way to measure temperature-dependent ruggedness. The examination of post-stress failure by ultrasonic scanning, decapsulation, OBIRCH/EMMI, and FIB-SEM showed that a series of degradation processes occur, starting with early charge trapping and slight shifts of leakage, then through the formation of localized hot-spots, weakening of the gate-oxide, and the erosion of metallization. Current crowding around the source region linked by a single bond wire was the cause of catastrophic failures, which caused a short between gate and source and between drain and source once thermal runaway and parasitic BJT activation had taken place. It was demonstrated that temperature is a strong accelerator of degradation, decreasing the avalanche capability and increasing structural damage. The SEM cross-section shows that the hotspot that develops at the corner of the p+ region where the highest accumulation of electric field takes place, causes p-well degradation during early failure. These results provide new insight into the thermal-electrical overstress limits of SiC MOSFETs and highlight the critical influence of packaging-dependent current distribution on avalanche reliability.

Developing a new cost-effective electrode that exhibits outstanding activity and high stability for electrochemical sensors is a challenging task. In this study, simple hydrothermal and ultrasonication techniques were employed to synthesize flower petal-like zinc molybdate embedded on graphene oxide sheets (ZnMoO4/GO) for the electrochemical detection of nitrofurantoin (NFT). The prepared ZnMoO4/GO nanocomposites were characterized using a range of spectrometric techniques. Electrochemical investigations confirmed that the sensing probe that utilized a ZnMoO4/GO modified electrode exhibited exceptional electroanalytical performance, enhanced electrical conductivity, and swift mass transport for NFT detection. Additionally, the prepared ZnMoO4/GO/GCE exhibited an extensive dynamic linear response range from 0.05 to 406.525 mu M, featuring a low detection limit of 0.024 mu M and remarkable sensitivity of 1.041 mu M-1 cm-2, along with notable interferents capability, storage stability, repeatability, and reproducibility. The GCE modified with ZnMoO4/GO successfully detected NFT in various environmental samples, as well as in biological samples during real-time monitoring analysis. These electrochemical tests provide a novel perspective on electrocatalytic activity, demonstrating satisfactory recoveries.

This study develops a Ga2O3 inserted semi-insulating microcolumns Schottky barrier diodes (Ga2O3 IMC-SBDs) with a simple process flow and low reverse leakage current. The inserted microcolumns effectively reduce the interfacial electric field in the region near the Schottky junction and decrease the effective anode area of direct metal/semiconductor contact, thereby significantly suppressing the reverse leakage current. The fabricated Ga2O3 IMC-SBDs exhibits a reverse leakage current about two orders of magnitude lower than that of a conventional SBDs at VR = 1000 V, while maintaining a breakdown voltage of 1807 V, a specific on-resistance of 4.1 mΩꞏcm2, and a rectification ratio on the order of 1010. This structure provides a feasible solution for device design and process simplification of high-voltage, low-leakage β-Ga2O3 SBDs.

Early detection of electrolyte-derived carbonate gases, particularly ethyl methyl carbonate (EMC), is crucial for preventing electrolyte leakage in lithium-ion batteries (LiBs), and oxide nanostructure-based resistive sensors offer an effective platform for their fast and sensitive detection. Following this approach, ordered porous tin oxide (SnO2) nanostructures were synthesized via a simple polystyrene sphere (PS) self-assembly templating method and decorated with 1-10 wt% bimetallic Au0.75Pt0.25 nanoparticles (NPs) to enhance EMC sensing performance. Structural and morphological analyses showed that the SnO2 framework, formed after PS-template removal, remained intact after loading with Au0.75Pt0.25 NPs, preserving a highly ordered, densely packed honeycomb-like architecture with hexagonally arranged hollow ring-like pores. Concurrently, oxygen vacancy and adsorbed oxygen concentrations increased notably (from 16.03% to 26.94% and 3.62% to 6.89%, respectively), providing abundant reactive sites to facilitate EMC adsorption to enhance overall sensing response. Among all samples, the 5 wt% Au0.75Pt0.25 sensor showed optimal EMC sensing performance, featuring a lower optimal operating temperature (190 degrees C), a higher response to 10 ppm (27.20), an ultra-low detection limit (50 ppb), rapid response/recovery times (21 s / 23 s), and improved humidity tolerance with response repeatability. The enhanced EMC sensing is credited to the synergistic catalytic and spillover effects of bimetallic Au-Pt NPs and the modulation of the SnO2 electronic structure induced by Au0.75Pt0.25-SnO2 heterojunction formation. These synergistic effects, along with the underlying EMC sensing mechanism, were explored thoroughly using energy band diagram-based analysis of the Au0.75Pt0.25-SnO2 heterojunctions. Overall, this research highlights an effective strategy for fabricating bimetallic NPs-modified sensing materials for reliable EMC detection and contributes to the advancement of sensors aimed at improving LiBs safety.

This work presents high-performance vertical NiO/GaN heterojunction diodes. A deep Helium-implanted edge termination (~800 nm) enables a record-high breakdown voltage of 1400 V, while oxygen plasma treatment and annealing achieve a low specific contact resistivity of 7.85×10−3 Ω•cm2. The devices exhibit a superior BFOM of 1.217 GW/cm2, with a low Ron,sp of 1.61 mΩ•cm2 and an on/off ratio of ~108. These results provide a promising route toward high-voltage, low-loss vertical GaN power devices.

Localized semi-insulating regions in beta-Ga2O3 are important for modulating the interfacial electric field and leakage characteristics of high-voltage devices. In this work, a high density of acceptor defects, including V-Ga and He-i, was introduced into the n-type Ga2O3 matrix by He-ion implantation, enabling the in situ formation of semi-insulating microcolumns in Ga2O3. These semi-insulating microcolumns effectively reduce the interfacial electric field near the Schottky junction and decrease the effective anode area of the direct metal/semiconductor contact, thereby significantly suppressing the reverse leakage current. The fabricated Ga2O3 SIMC-SBDs exhibit a leakage current nearly two orders of magnitude lower than that of conventional SBDs at a reverse voltage of 1000 V, while maintaining a breakdown voltage of 1807 V and a specific on-resistance of 4.1 m Omega cm(2). This structure provides a viable approach to the design of beta-Ga2O3 SBDs with high blocking capability and low leakage current while simplifying the fabrication process.

Abstract In this work, the polystyrene (PS)-templated three-dimensional (3D) ordered, hollow, and porous In2O3 structures-based chemiresistive sensors for isoprene detection in the range of 100 ppb–5 ppm are investigated. The morphology of the In2O3 structure was controlled by different PS sphere sizes of 200, 500, 700, 1000 nm, and 1500 nm, respectively. The materials were investigated through various characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET) characterization techniques. The In2O3-500 sensor exhibited a maximum response (Ra/Rg) of 4.32–5 ppm isoprene concentration at an operating temperature of 270 °C, an experimental detection limit of 100 ppb, a low theoretical detection limit of 6.50 ppb, and quick response/recovery times of 14/14 s, respectively. The sensor’s response was also examined under humidity exposure of 30% RH to 80% RH, repeatability over 3600 s, and long-term stability of 11 days under 5 ppm isoprene concentration at operating temperature of 270 °C. The notable sensing performance of In2O3 to isoprene is attributed to the controlled morphology, porous structure, low gas transport resistance, and an effective electron transfer between In2O3 material and isoprene through an active modulation of the depletion layer. This study delivers a template-based method to effectively control the morphology, structures, and response characteristics of metal oxides for gas sensing applications.

ABSTRACT Integrating 2D and 3D semiconductors via van der Waals (vdW) heteroepitaxy offers significant opportunities for multifunctional optoelectronics. However, conventional devices often face limited detection ranges and inadequate noise suppression. We report a wafer‐scale vertical p‐Mo x Nb 1‐x S 2 /n‐GaN vdW heterojunction photodetector, rationally engineered with precisely regulated p‐type doping and Type‐II band alignment. This architecture facilitates a carrier separation efficiency of 92% and a superior responsivity of 688.1 A/W, endowing the device with an ultrahigh optical gain of 65 500, a specific detectivity of 1.66 × 10 14 Jones, and a noise‐equivalent power of 3.13 × 10 −17 W Hz −12 . Spanning the ultraviolet‐to‐visible regime (365–660 nm), these performance metrics outperform state‐of‐the‐art Si and InGaAs detectors by orders of magnitude. The synergistic interplay between the vertical transport pathway and optimized material composition enables rapid temporal responses and exceptional noise suppression. Beyond conventional imaging, the detector achieves centimeter‐level environmental perception accuracy, directly fulfilling the requirements of intelligent driving and machine vision. This study establishes an innovative material–architecture paradigm for GaN‐compatible optoelectronics, laying a foundation for next‐generation autonomous sensing platforms.

In this work, a ReMoS2 2-D material was grown on a sapphire planar substrate (FS) by chemical vapor deposition (CVD), and transferred to a gallium nitride patterned substrate (PGS) by a wet-transfer process to prepare ReMoS2/FS and ReMoS2/PGS photodetectors. Compared with the performance of the ReMoS2/FS photodetector, the ${I}_{\mathbf {light}}$ / ${I}_{\mathbf {dark}}$ of the ReMoS2/PGS photodetector is ${1.35} \times {10}^{{3}}$ , the responsivity is 91 A/W, and the detectivity is ${4.1} \times {10}^{{10}}$ Jones under the irradiation of light with a wavelength of 460 nm, which are increased by 46, 56, and 151 times, respectively. At the same time, the ReMoS2/PGS photodetector also has imaging capability and communication function.

Bifunctional photocatalysts have been shown to establish a versatile platform for advancing diverse photocatalytic processes, with the potential to integrate multiple reaction pathways within a single catalytic system. A ternary S-scheme heterostructure photocatalyst consisting of g-C3N4, ZIF-8 and single-atom Ag is synthesized by in situ growing ZIF-8 on g-C3N4, followed by atomic-level Ag modification. This system leverages the S-scheme heterostructure to maintain high redox potentials and improve charge separation. Moreover, the incorporated Ag single atoms lower the Gibbs free energy barrier, synergistically boosting the overall photocatalytic efficiency. This well-designed configuration dramatically enhances photocatalytic performances, with hydrogen and ammonia evolution rates 22 and 3 times higher than those of pure ZIF-8, respectively. The present study demonstrates the pivotal role of integrating S-scheme heterostructures with single-atom engineering in highly efficient photocatalysts.

Developing advanced sensing interfaces with high conductivity, abundant redox activity, and tunable porous architectures is essential for improving electrochemical biosensor performance. Herein, we report a threedimensional (3D) ordered porous film based on a MXene and polyoxometalate (POM) hybrid, constructed via the breath figure method. This simple, green strategy enables the formation of uniform honeycomb-like architectures with tunable porosity and enlarged electroactive surface area. The integration of MXene's high conductivity, POM's rich redox and molecular recognition capabilities, and the porous structure synergy imparts the film with superior electrochemical performance. When employed as a sensing platform for dopamine (DA) detection, the porous MXene/POM film achieves a low detection limit of 58.69 nM. The sensor also demonstrates excellent selectivity against common interferents such as uric acid (UA), maintaining a detection limit of 59.98 nM in its presence. Moreover, it exhibits excellent repeatability, reproducibility, and long-term stability. Practical applicability is further confirmed through the quantification of DA in diluted human urine samples via the standard addition method, with recovery rates ranging from 98.2 % to 102.1 % and relative standard deviations below 2.9 %. This study offers a scalable and eco-friendly approach for engineering high-performance porous MXene-based sensing films and offers valuable insights into interfacial design for real-sample electrochemical biosensing.

In this work, a series of polystyrene (PS) templated p-Cr2O3/n-In2O3 composite materials such as Cr2O3/In2O3:0.46, Cr2O3/In2O3:0.91, Cr2O3/In2O3:1.37, and Cr2O3/In2O3:1.83 were successfully prepared using a solution immersion method and further utilized for isoprene detection. The materials electrical, optical, and morphological properties were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and Brunauer-Emmett-Teller (BET) characterization techniques. Among all sensors, the Cr2O3/In2O3:0.91 composite sensor exhibited the remarkable gas sensing properties with a response of 8.29, experimental detection limit of 5 ppb, response/recovery time of 51s/71s, good long-term stability in humidity range of 30–80% RH, and excellent repeatability of over 2500s to 5 ppm isoprene gas at optimal operating temperature of 190 ˚C. The high-performance exhibited by p-Cr2O3/n-In2O3 materials could be ascribed to the more oxygen vacancies (VO) and the ample heterojunctions present between Cr2O3 and In2O3 interfaces. This study presents a method using a template-based technique to effectively control the structure of metal oxide materials and improve time-response characteristics for high-performance gas sensing.

In this study, proton irradiation is employed to fabricate semi-insulating GaN free-standing wafers with a sheet resistance of 5.9 × 107 Ω/sq. The mechanism for achieving semi-insulating GaN via proton irradiation is associated with the formation of a deep-level trap (EC-0.54 eV), which is tentatively attributed to nitrogen antisite-related defects (NGa). GaN-on-GaN high electron mobility transistors fabricated on the irradiated substrates exhibit stable operation over 300–375 K, with a minimum noise figure as low as 0.25 dB, with suppressed low-frequency noise characteristics. Additionally, the proton irradiation treatment GaN substrate also exhibits high volume production potential. This device is ideal for installation in harsh operational environments, such as satellite communication systems or outdoor base stations.

The calculation of phonon scattering coefficients is used to study the influence of different structures on glass-like thermal conductivity.