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The ongoing trend towards downsizing silicon (Si)-based metal-oxide semiconductor (MOS) devices has led to constraints on the silicon dioxide (SiO 2) gate dielectric due to increased leakage current through the thin SiO 2. In this study, ytterbium oxide (Yb 2 O 3) as a high dielectric constant (k) gate oxide material was deposited on a Si substrate and subjected to annealing at different temperatures ranging from 400 to 1000oC in a nitrogen-oxygen-nitrogen ambient atmosphere. The successful formation of Yb 2 O 3 was verified using X-ray diffraction (XRD), Fourier transform infrared (FTIR), and ultraviolet–visible (UV–VIS) spectroscopy. The FTIR analysis indicated that Yb 2 O 3 gate dielectrics post-annealing exhibited Yb-O bonding due to oxygen diffusion, as well as N-O bonding and NO 3 -bonding, demonstrating the formation of a nitrogen barrier at the interface to hinder oxygen diffusion. The optical band gap values of Yb 2 O 3 gate dielectrics post-annealing ranged from 3.092 eV to 3.267 eV. Notably, the Yb 2 O 3 gate dielectric annealed at 800 °C showed no breakdown within the 0–3 V range across all samples. The acquisition of a high k value of 19.40 and a low effective oxide charge (Q eff) of 5.32 x 1011 cm−2, along with the superior I-V characteristics, suggest that the Yb 2 O 3 gate dielectric annealed at 800oC has the potential to be employed for next generation MOS applications. [ABSTRACT FROM AUTHOR]

Herein, the Hf0.5Zr0.5O2/nAl2O3/Hf0.5Zr0.5O2 (HZO/nAO/HZO) nanolaminates, where n represents the thickness of AO insertion layer (IL), were fabricated via atomic layer deposition with varying AO IL thicknesses. The crystal structure, ferroelectric (FE), leakage, and fatigue properties of HZO/nAO/HZO nanolaminates were systematically investigated. The results reveal that grain size of the HZO/nAO/HZO nanolaminates reduced with increasing AO IL thickness. The remanent polarization (2Pr) values first increased and then decreased with thicker AO IL. Notably, the HZO/5AO/HZO nanolaminates exhibited a maximum 2Pr value of 35.0 μC/cm2 (@ ~ 2.67 MV/cm) when the AO IL thickness is 5 Å. This value not only surpasses that of single-layer HZO film (31.8 μC/cm2) but also exceeds the previously reported value for similar HZO-based MFIFM structures (23.6 μC/cm2 @ ~ 4.0 MV/cm). This enhancement in 2Pr is a key achievement that sets this work apart. Furthermore, the incorporation of AO IL effectively disrupts the continuous growth of HZO film, resulting in a significant reduction in leakage current by approximately two orders of magnitude, and the breakdown field is increased by 66.7%. This is critical for improving the reliability and durability of HZO-based FE devices. Therefore, the monolayer HZO film showed a prolonged wake-up effect until experiencing hard breakdown after only 4.4 × 107 cycles. Whereas, the HZO film embedded with 5 Å AO IL demonstrated enhanced endurance, achieving up to 2.5 × 109 cycles. The present work confirms that the identification of an optimal thickness (5 Å) for the AO IL, which effectively balances the enhancement of FE properties and the reduction of leakage current, represents a significant contribution. This discovery offers valuable guidance for designing HZO-based devices to achieve optimal performance. [ABSTRACT FROM AUTHOR]

GaN is rapidly gaining attention for implementation in power electronics but is still impacted by its high density of threading dislocations (TDs), which have been shown to facilitate current leakage through devices limiting their performance and reliability. Here, we discuss a novel implementation of photoluminescence (PL) imaging to study TDs in regions within vertically structured p-i-n GaN (PIN) diodes consisting of metalorganic chemical vapor deposition (MOCVD) epitaxial layers grown on ammonothermal GaN (am-GaN) substrates. PL imaging with a sub-bandgap excitation energy (3.1 eV) reveals TDs with excellent clarity in three dimensions within the am-GaN substrate. Galvanometric-driven PL imaging allows the microstructure of hundreds of devices to be characterized in a single session, enhancing the screening process through the addition of device specific TD location tracking and density mapping. The visibility, structural characteristics, luminescent nature and evolution of TDs through the GaN growth process are described, potentially providing the ability to define TD structures associated with leakage current. [ABSTRACT FROM AUTHOR]

The morphotropic phase boundary (MPB) is particularly crucial for high piezoelectric performance of perovskite ferroelectrics. This study focus on the shift of MPB and its impacts on the piezoelectric properties of (1- x)Bi 0.997 La 0.003 FeO 3 - x BaTiO 3 ferroelectric ceramic. Although appropriate La doping reduces leakage current, the phase boundary is moved towards tetragonal (T) phase. By adjusting BaTiO 3 component, the concentration of rhombohedral (R) and T phase is restored back to almost equality at x = 0.295, achieving optimal piezoelectric properties (d 33 = 179 pC/N, k p = 33.06 %). Furthermore, through applying quenching on 0.30 ≤ x ≤ 0.32 samples occupied mainly by T phase, a higher d 33 value of 205 pC/N and a remarkable amplification of d 33 (about 40 %) are both realized at x = 0.32, which is ascribed to the shift of R/T phase ratio close to 1:1. These results confirm the importance of phase boundary movement and provide an effective approach for performance enhancement of BiFeO 3 -BaTiO 3 system. [ABSTRACT FROM AUTHOR]

This study investigates the structural, electrical, leakage current, and magnetic characteristics of the double perovskite material Nd2NiTiO6 synthesized through the sol–gel citrate auto‐ignition method. The Rietveld refinement of the X‐ray diffraction patterns confirmed a monoclinic symmetry (space group P21/n) with an ordered arrangement of alternate NiO6 and TiO6 octahedra. Impedance spectroscopic analysis exhibited the material's non–Debye‐type relaxation mechanism and semi‐conductive nature. AC conduction analysis revealed that the conduction of charge carriers occurs via the nonoverlapping small polaron hopping mechanism, consistent with Mott's variable range hopping model. Temperature‐ and frequency‐dependent dielectric measurements were interpreted using the Maxwell–Wagner interfacial polarization model. The analysis of thermal‐ and field‐dependent leakage currents established that conduction is ohmic, which the Schottky barrier model explains. Studies on magnetization ruled out the presence of magnetic ordering connected to indirect interaction between Ni2+ ions via Ti4+ ions and the rare‐earth cation (Nd3+) moment. [ABSTRACT FROM AUTHOR]

Incorporating specific defects into complex oxides facilitates the exploration of exotic phenomena and novel functionalities based on the intricate coupling between the defects and lattice/charge. However, methods for maximizing the density of specific defects while enhancing the desired properties have been rarely explored. In this study, the effect of N+ ion bombardment‐driven specific defects on the properties of bismuth ferrite (BFO) thin films was investigated. Furthermore, atomic structure characterization and computational processing revealed the displacement and orientation of the Fe atoms, which are linearly related to the degree of polarization. The ion bombardment introduced deep‐level trap states within the lattice, leading to a significant reduction in the leakage current and improved insulation performance of the films. By precisely engineering the defect content through N+ ion bombardment, the pure BFO thin films with remarkable and stable ferroelectric properties (remnant polarization, Pr = ∼116.8 µC·cm−2; leakage current, J = ∼1.5 × 10−8 A·cm−2) were fabricated. This innovative defect engineering‐based approach enables the customization and optimization of local ferroelectric order parameters, thereby establishing a solid foundation for designing functionalities across various functional material systems. [ABSTRACT FROM AUTHOR]

High leakage current density and relatively low piezoelectric activity have become one of the main obstacles to expanding the practical application of Bi4Ti3O12 (BIT) high-temperature piezoelectric ceramics. Although ion doping can improve electrical resistivity and piezoelectric response, it often lowers the Curie temperature. In this work, by introducing CaBi2Nb2O9 (CBN) with higher Curie temperature to BIT, a composite ceramic (1−x)BIT-xCBN was designed, and the effect of CBN content on the structure and electrical properties of the ceramics was investigated. With the increase in the x value, the intensity of the highest peak (117) gradually decreased until disappearing, while the intensity of peak (115) gradually increased, and the X-ray diffraction (XRD) refinement results showed that some non-stoichiometric compounds, Bi1.74Ti2O6.624 and Ca0.5Bi2.5Ti0.5Nb1.5O9, were produced. The sheet-like grains were effectively suppressed, while the granular grains became prominent with high CBN doping content, which should contribute to improving the electrical resistivity of ceramics. The optimal electrical properties were obtained in 0.8BIT-0.2CBN composite ceramics as follows: the piezoelectric coefficient d33 = 13.8 pC/N, the Curie temperature TC = 765°C, and the electrical resistivity ρdc = 8.52 × 105 Ω·cm (@ 500°C). In addition, the d33 maintained 89.1% of the initial value after annealing at 550°C, showing good thermal stability for high-temperature sensing applications. [ABSTRACT FROM AUTHOR]

A novel AlGaN/GaN high-electron mobility transistor (HEMT) is put forward to promote its breakdown characteristics and anti-single-event transient (SET) effect. The features of the proposed device are a hybrid GaN/AlN buffer layer and a uniform-groove high-k passivation layer between the gate and drain electrodes (HGKB-HEMT). First, the uniform-groove high-k passivation layer not only reduces the peak electric field at the gate edges, but also modulates the electric field distribution between the gate and drain. Therefore, the breakdown voltage (BV) and the anti-SET effect show a great improvement. Second, the buffer leakage current was effectively reduced by the hybrid buffer layer, resulting in a further increase in the BV. The BV of the HGKB-HEMT reached 1672 V, which is 82.7% higher than the conventional GaN HEMT, and the peak drain current induced by the SET effect of the HGKB-HEMT decreased by 60.7% at VDS = 50 V. Moreover, the channel current of the HGKB-HEMT increased slightly and the on-state resistance decreased. [ABSTRACT FROM AUTHOR]

Pristine ZnO and Sm-doped ZnO nanoparticles were synthesized using a wet chemical co-precipitation technique. The morphological and structural characteristics of pristine and Sm-doped ZnO were studied by field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) techniques. Increases in lattice parameters, interplanar spacing, and volume was observed from the XRD patterns compared to its JCPDS card. Crystallite size, dislocation density, deformation stress, lattice strain, and energy density for both pristine and Sm-ZnO nanoparticles were calculated using Scherrer and Williamson–Hall (W–H) methods. An energy bandgap reduction was observed in the Sm-doped ZnO (Eg ~ 2.7 eV), which played a crucial role in explaining the increased leakage currents in Sm-ZnO. The Sm-doped ZnO nanoparticles exhibited a remnant polarization (Pr ~ 0.163 µC/cm2) and a coercive field (Ec ~ 25.33 kV/cm). Current–voltage (I–V) characteristics show maximum current generated on applying varying voltages (Vmax = 40 V, Imax = ~600 μA). Frequency- and temperature-dependent dielectric studies were conducted to examine the change in the values of the dielectric constant and dielectric loss with the variation in frequency and temperature. The Sm-doped ZnO-based nanogenerator generated an output voltage ~ 400 mV at tapping force of ~ 0.02 kgf, which makes it a prominent candidate for self-powered devices. [ABSTRACT FROM AUTHOR]

This study investigates the structural, electrical, leakage current, and magnetic characteristics of the double perovskite material Nd2NiTiO6 synthesized through the sol–gel citrate auto‐ignition method. The Rietveld refinement of the X‐ray diffraction patterns confirmed a monoclinic symmetry (space group P21/n) with an ordered arrangement of alternate NiO6 and TiO6 octahedra. Impedance spectroscopic analysis exhibited the material's non–Debye‐type relaxation mechanism and semi‐conductive nature. AC conduction analysis revealed that the conduction of charge carriers occurs via the nonoverlapping small polaron hopping mechanism, consistent with Mott's variable range hopping model. Temperature‐ and frequency‐dependent dielectric measurements were interpreted using the Maxwell–Wagner interfacial polarization model. The analysis of thermal‐ and field‐dependent leakage currents established that conduction is ohmic, which the Schottky barrier model explains. Studies on magnetization ruled out the presence of magnetic ordering connected to indirect interaction between Ni2+ ions via Ti4+ ions and the rare‐earth cation (Nd3+) moment. [ABSTRACT FROM AUTHOR]

Multiferroic materials, which exhibit coupled ferroelectric and magnetic properties, hold immense promise for multifunctional device applications. Here, a multistep synthesis method, involving chemical synthesis, mechanical milling, and Spark Plasma Sintering, was utilized to fabricate (1-x)BaTiO3-xCoFe2O4 (BTO-CFO) compacted ceramics composites with x = 0.1, 0.2, 0.3, and 0.4. Controlled high pressure and pulsed current facilitated rapid densification, yielding high-density fine microstructures. Structural analysis confirmed the coexistence of tetragonal BaTiO3 (BTO) and cubic spinel CoFe2O4 (CFO) phases, forming 0–3 type multiferroic composites. Microstructural analysis revealed CFO grain clustering within the BTO matrix. The temperature-dependent magnetization curve of CFO shows an increase in magnetization within the temperature range of BTO ferroelectric phase transition, suggesting a strain-mediated magnetoelectric coupling. Temperature and frequency dependence of dielectric permittivity highlighted significant CFO conductivity contribution. Ferroelectric hysteresis and magnetoelectric coupling were observed predominantly in low CFO content samples, with differences in magnetoelectric coefficient values attributed to preferential ferroelectric polarization alignment. Our findings suggest that achieving high interface coupling is very challenging due to high leakage current from the magnetic phase. [ABSTRACT FROM AUTHOR]

BiFeO 3 (BF) based ceramics are inspiring great interest in advanced pulsed power applications owing to their giant spontaneous polarization, meanwhile limited by the significant leakage current. In this work, Sr 0.7 Bi 0.2 TiO 3 (SBT) modified 0.7BiFeO 3 -0.3BaTiO 3 (BF-BT) ternary lead-free relaxor ferroelectric ceramics are investigated to elaborate the dielectric performances, including the impedance, relaxor behavior, ferroelectric and energy storage, and strain properties. The substitution of SBT induces a phase transition from an R 3 c to an average pseudo-cubic structure and forms a secondary phase at high dopants. Simultaneously, the resistivity, electrically homogeneous, and band gaps are increased significantly, related to the inhibition of oxygen vacancy formation. Besides, the ferroelectric long-range order is disrupted, which promotes the formation of local defect fields and polar nanoregions. The structural heterogeneity for the higher doped components leads to an increased relaxation behavior with an almost hysteresis-free polarization response to external electric fields. Excellent temperature-insensitive dielectric response and promising dielectric energy storage properties in low electric fields are achieved, respectively. These results indicate that the SBT modification is an effective route in regulating the dielectric performance of bismuth ferrite based relaxors. [ABSTRACT FROM AUTHOR]

The advancement in high-performance computing technologies, including quantum and aerospace systems, necessitates components that operate efficiently at cryogenic temperatures. In this study, we demonstrate a hafnia-based ferroelectric tunnel junction (FTJ) that achieves a record-high tunneling electroresistance (TER) ratio of over 200,000 and decade-long retention characteristics. By introducing asymmetric oxygen vacancies through the strategic use of indium oxide (InOx) layer, we enhance the TER ratio without increasing off-current, addressing the longstanding issue of low on-current in hafnia-based FTJs. Unlike prior approaches that led to leakage currents, our method optimizes tunneling behavior by leveraging the differential oxygen dissociation energy between InOx and hafnium zirconium oxide (HZO). This results in asymmetric modulation of the tunnel barrier, enhancing electron tunneling in one polarization state while maintaining stability in the opposite state. Furthermore, we explore the intrinsic characteristics of the FTJ at cryogenic temperatures, where reduced thermal energy minimizes leakage currents and allows the maximization of device performance. These findings establish a new benchmark for TER in hafnia-based FTJs and provide valuable insights for the integration of these devices into advanced cryogenic memory systems. [ABSTRACT FROM AUTHOR]

This article suggests a nine‐level (9L) seven‐switch (7S) transformer‐less (TL) common‐ground (CG) switched capacitor (SC) inverter with double boosting capability. The proposed 9L7S‐CGSC‐TL inverter comprises only seven switches (7S), two diodes, three self‐balanced capacitors, and one DC source. The suggested inverter has a CG connection which eliminates ground leakage currents. Additionally, the suggested topology necessitates fewer conducting devices, thereby reducing conduction losses. The voltage across every capacitor is automatically balanced within each fundamental cycle. The proposed topology has been evaluated based on parameters such as component count, total harmonic distortion, cost, and efficiency. The proposed configuration switching sequence is governed by employing the level‐shifted pulse width modulation technique. A power loss study was conducted to determine the efficiency of the proposed switched capacitor multilevel inverter (SCMLI) under different load conditions in PLECS. The results shows that the proposed SCMLI achieves a peak efficiency of 98.17%. Further, the lifespan of the proposed SCMLI is assessed through a reliability assessment. The simulation and experimental results at different conditions are presented and elucidated. [ABSTRACT FROM AUTHOR]

This work presents a novel tape‐casting method for producing flexible, graphene‐enhanced diatomite ceramic sheets. These sheets target dielectric substrates for applications in the critical yet under‐explored, high‐frequency range. Structural and morphological analyses confirmed the incorporation of graphene nanoplatelets into the ceramics matrix, validating the efficiency of the tape‐casting process. The results show the crucial role of the composite's crystalline structure in its dielectric response, where oxygenated functional groups within the graphene nanoplatelets act as intrinsic barriers to restrict leakage current, resulting in low dielectric loss. Doping of flexible ceramic plates with graphene nanoplatelets led to significant dielectric variations of approximately 100% over a wide frequency range. The capacitance increased by 215.35%$\%$ with the addition of 10 wt.%$\%$ graphene compared to pure diatomite. Our results demonstrate the ability to adapt the framework's structural, morphological, and dielectric properties through doping with graphene in diatomite, offering promising prospects for applying flexible ceramic sheets at high frequency. [ABSTRACT FROM AUTHOR]

Sintering temperature is decisive for optimizing the grain boundary environment to obtain the high performance ZnO based varistor ceramic. In this work, the impacts of sintering temperature on microstructure and electrical properties of ternary Zn-Sr-Co varistor were investigated. It was found that the distribution of Sr, the critical factor to form grain boundary, was heavily sensitive to sintering temperature. The considerable Sr ions precipitated at grain boundaries and formed the clusters of SrZnO 2 while the sintering temperature increases from 1150 °C to 1190 °C. Besides, the precipitation of Sr led to the large segregation of Co at grain boundaries. The enrichment behavior of Sr and Co contributed to the optimization of grain boundaries, resulting in the enhanced barrier height. As a result, the excellent nonlinear current-voltage performances, i.e., the high nonlinear coefficient of 56.47 and the low leakage current density of 0.73 μA/cm2 were obtained in the ternary ZnO-SrCO 3 -Co 2 O 3 varistor sintered at 1190 °C. However, the grain boundary environment would be destroyed by the excessive temperature of 1210 °C, resulting in the degradation of grain boundary barrier and especially a surge in the leakage current I L from 0.73 to 92.19 μA/cm2. In addition, varying sintering temperature has the important effects on impedance and dielectric properties of the ZnO-SrCO 3 -Co 2 O 3 varistors. The findings provide new perspectives for developing the high-performance ternary ZnO-SrCO 3 -Co 2 O 3 varistor ceramics by optimizing the initial grain boundary environment at different sintering temperatures. [ABSTRACT FROM AUTHOR]

With the increasing demand for modern high‐voltage electronic devices in electric vehicles and renewable‐energy systems, power semiconductor devices with high breakdown fields are becoming essential. β‐Gallium oxide (Ga2O3), which has a theoretical breakdown field of 8 MV cm−1, is being studied as a next‐generation power‐switch material. However, realizing a breakdown field close to this theoretical value remains challenging. In this study, an aerosol deposition‐manufactured Ga2O3 film boasting an extremely high breakdown field, achieved through thickness optimization, heat treatment, and a unique nozzle‐tilting method, is developed. This study explores the effect of oxygen vacancies on the dielectric constant, breakdown field, and microstructure of Ga2O3 films. Through these methods, Ga2O3 films with a denser (98.88%) and uniform surface, made less affected by oxygen vacancies through nozzle tilting and post‐annealing at 800 °C, are produced, resulting in appropriate dielectric constants (9.3 at 10 kHz), low leakage currents (5.8 × 10−11 A cm−2 at 20 kV cm−1), and a very high breakdown field of 5.5 MV cm−1. The results of this study suggest that aerosol‐deposited Ga2O3 layers have great potential to enable power switches with reliable switching. [ABSTRACT FROM AUTHOR]

Doped Hf 0.5 Zr 0.5 O 2 materials have drawn increasing attention due to the excellent ferroelectric properties, but the relevant research is just in the preliminary stage and the reported doped systems are rare. In this work, Ca doped Hf 0.5 Zr 0.5 O 2 (Ca:HZO) ferroelectric films were successfully fabricated via chemical solution deposition and investigated for the first time. It is observed that Ca doping induces a phase transformation from monoclinic to orthorhombic/tetragonal and then to monoclinic/tetragonal. The highest orthorhombic phase fraction is achieved in 2.5 mol% Ca doped HZO film, contributing to the optimum ferroelectric property with the largest remnant polarization of 14.00 μC/cm2 after 105 cycles. Additionally, the leakage current density is observed to decrease with increasing Ca content, which is mainly associated with the changes of grain size and surface roughness. As a result, the endurance is significantly improved in the Ca doped films, and an excellent endurance of 1010 cycles is achieved in the 2.5 mol% Ca doped film. These results suggest that Ca doping can enhance the ferroelectric and endurance properties of HZO films by optimizing the phase and morphological structure. [ABSTRACT FROM AUTHOR]

Silicon carbide particle reinforced aluminum matrix composites (SiCp/Al), combine the properties of aluminum matrix materials and reinforced silicon carbide (SiC) particles, finding widespread application in aerospace, optics, and electronics. The increased hardness and electrochemical inertness of SiC particles present significant challenges in their processing. This research investigates the impact of photocatalytic processes on machining accuracy in electrochemical processing (ECM). The dissolution characteristics of SiCp/Al during ECM and photocatalytic-assisted electrochemical machining (PAECM) were analyzed with varying electrolyte compositions, using polarization curves and oxidation–reduction potential (ORP). Validation of improved machining accuracy and surface quality in PAECM was achieved through no-feeding machining. According to theoretical principles and laboratory analyses of the workpiece surface, it was found that PAECM, through its photocatalytic reaction, generated more oxides, blocked stray currents and stray corrosion effectively, and attained accuracy in profile creation. Through a comparative analysis it revealed that PAECM exhibited smoother profiles and reduced Overcut Ratio (OCR) in hole and groove machining compared to ECM, particularly in groove machining. Adjusting machining gaps as well as reducing abrasive particle size in PAECM influenced groove depth and width, which achieved optimal morphology with a 0.4 mm gap and a 2–3 nm abrasive particle size, resulting in a 370 μm depth. [ABSTRACT FROM AUTHOR]

Nanofilm CdS@Cd/Si heterojunctions have been fabricated by a two-step method. The obvious rectification effect can be observed. However, the leakage current density is relatively large. According to the criterion for judging the conduction model, three conduction mechanisms can be observed, which are the thermally generated electrons model, the Ohmic model and the space-charge-limited-current model from low voltage to high voltage, respectively. The preparation process of nanofilm CdS@Cd/Si heterojunctions by this two-step method, which directly grows nanofilm CdS@Cd on the silicon substrate to construct heterojunctions, can reduce the introduction of excessive defects and facilitate the release of stress in the interface. [ABSTRACT FROM AUTHOR]

This study investigated the effects of 5 MeV proton irradiation on the static electrical characteristics of Ni/β-Ga2O3 Schottky barrier diodes without and with NiO rings (SBDs and RSBDs), with a total irradiation fluence of 1 × 1013 cm−2. The results indicated that the proton irradiation damage decreased the current level of the SBDs and RSBDs due to the reduced net carrier concentration of β-Ga2O3 by about 50% other than the impact on the Schottky contact. On the one hand, the reduced net carrier concentration increased the on-resistance, resulting in a reduction in the forward saturation current by approximately one order of magnitude. On the other hand, because the leakage current mechanism was dominated by the Poole–Frenkel emission process and Fowler–Nordheim tunneling process, the reduced net carrier concentration degraded the electric fields in the irradiated SBDs and RSBDs, reducing the effect of the NiO guard ring and, meanwhile, leading to a lower leakage current after proton irradiation. In addition to being associated with the temperature-dependent current–voltage (I–V–T) results, the proton irradiation also suppressed the Poole–Frenkel emission process and increased the tunneling barrier height of SBDs and RSBDs. In this case, the breakdown voltage of the SBDs and RSBDs increased by approximately 2–4 times. In addition, the Technology Computer Aided Design simulations showed a reduced discrepancy between the peaks of the electric field of SBDs and RSBDs after irradiation, leading to the comparable leakage current of SBDs and RSBDs, which confirmed the weakening of the NiO guard ring's effect. [ABSTRACT FROM AUTHOR]

The electrical properties and performance characteristics of niobium dioxide (NbO 2)-based threshold switching devices are examined at cryogenic temperatures. Substoichiometric Nb 2 O 5 was deposited via magnetron sputtering and patterned in microscale (2 × 2 − 15 × 15 μ m 2) crossbar Au/Ru/NbO x /Pt devices and electroformed at 3–5 V to make NbO 2 filaments. At cryogenic temperatures, the threshold voltage (V th ) increased by more than a factor of 3. The hold voltage (V h ) was significantly lower than the threshold voltage for fast voltage sweeps (200 ms per measurement). If the sample is allowed to cool between voltage measurements, the hold voltage increases, but never reaches the threshold voltage, indicating the presence of nonvolatile Nb 2 O 5 in the filament. The devices have an activation energy of E a ≈ 1.4 eV, lower than other NbO 2 devices reported. Our work shows that even nominally "bad" selector devices can be improved by reducing the leakage current and increasing the sample resistance at cryogenic temperatures. [ABSTRACT FROM AUTHOR]

This work evaluates the impact of applying hydrogen plasma (H-plasma) either after the deposition of the ZrO2 layer or as an intermediate step during the deposition on the performance of resistive random-access memory devices. Devices treated with H-plasma exhibited lower power consumption during the forming process and a higher Ron/Roff ratio over 50 cycles of SET and RESET pulses compared to untreated devices. The position of the plasma treatment significantly influenced the device's performance. We measured the leakage current, which correlates well with the forming process. Devices with higher leakage current required less power during the forming process. It was observed that a thicker capping layer following plasma insertion reduced forming power and improved the conductance quantization for multilevel cell characteristics. [ABSTRACT FROM AUTHOR]

This study presents and examines the feasibility of a dual metal gate ferroelectric germanium heterojunction-based step channel double-gate tunnel field-effect transistor (SC-DMTFET) to eliminate issues pertaining to drive current, subthreshold swing, and leakage current, concurrently decreasing ambipolar behavior resulting from structural similarities between the source and drain ends. Mitigating the consequences of ambipolar effects is the purpose of the study. The performance of the proposed structure was assessed and compared to that of a single metal gate, both with and without a step channel, by utilizing various TCAD simulation parameters. An analysis of the energy diagram, carrier concentration, electric field, drain characteristics, surface potential, and analog/radio frequency (RF) parameters was conducted to evaluate the electrostatic behavior of all the structures. The proposed structure yields minimum OFF current of 2.10 × 10−17 A/μm and maximum ON current of 2.33 × 10−3 A/μm. Also, the SC-DMTFET exhibits the highest current ratio of ≃1014 and the minimum subthreshold slope of 26.17 mV/decade in all designed structures. [ABSTRACT FROM AUTHOR]

ZnO varistor samples generally have poor preparation repeatability. In this work, ZnO varistor samples A and B with the same preparation technique showed significant differences in properties, and the reasons were explored in detail. Nonlinear coefficient (α) values of 42.59 and 72.68, and leakage current density of 0.013 mA/cm2 and 0.002 mA/cm2 were found for samples A and B, respectively, which are markedly different between the samples. However, samples A and B showed the same phases. In addition, samples A and B exhibited mean grain size (d) of 2.21 μm and 2.47 μm, double Schottky barrier height (φB) of 0.45 eV and 0.48 eV, and grain boundary resistivity (ρgb) of 5.32 × 106 Ω m and 5.40 × 106 Ω m, respectively, which were all similar between the two samples. According to the low-temperature dielectric spectral analyses, the values of k1 of samples A and B, reflecting the concentration of interstitial zinc, were 14.06 and 11.09, and the values of k2 reflecting the concentration of oxygen vacancy were 7.48 and 3.35, respectively. Therefore, the obvious difference in the electrical properties between samples A and B may be caused mainly by the obvious difference in the concentration of oxygen vacancy. Thus, this work provides evidence of the effects of oxygen vacancy on the electrical properties of ZnO varistors. [ABSTRACT FROM AUTHOR]

Tantalum electrolytic capacitors have performance advantages of long life, high temperature stability, and high energy storage capacity and are essential micro-energy storage devices in many pieces of military mechatronic equipment, including penetration weapons. The latter are high-value ammunition used to strike strategic targets, and precision in their blast point is ensured through the use of penetration fuzes as control systems. However, the extreme dynamic impact that occurs during penetration causes a surge in the leakage current of tantalum capacitors, resulting in a loss of ignition energy, which can lead to ammunition half-burst or even sometimes misfire. To address the urgent need for a reliable design of tantalum capacitor for penetration fuzes, in this study, the maximum acceptable leakage current of a tantalum capacitor during impact is calculated, and two different types of tantalum capacitors are tested using a machete hammer. It is found that the leakage current of tantalum capacitors increases sharply under extreme impact, causing functional failure. Considering the piezoresistive effect of the tantalum capacitor dielectric and the changes in the contact area between the dielectric and the negative electrode under pressure, a force–electric simulation model at the microscale is established in COMSOL software. The simulation results align favorably with the experimental results, and it is anticipated that the leakage current of a tantalum capacitor will experience exponential growth with increasing pressure, ultimately culminating in complete failure according to this model. Finally, the morphological changes in tantalum capacitor sintered cells both without pressure and under pressure are characterized by electron microscopy. Broken particles of Ta–Ta2O5 sintered molecular clusters are observed under pressure, together with cracks in the MnO2 negative base, proving that large stresses and strains are generated at the micrometer scale. ARTICLE HIGHLIGHTS: HIGHLIGHTS • The failure phenomenon of a notable surge in leakage current in two commonly used tantalum capacitors under dynamic impact is investigated. • A mechanical–electrical model for tantalum capacitor electrodes is established at the microscale, and we the complete failure of tantalum capacitors under higher impacts is anticipated. • Morphological changes in tantalum capacitor sintered cells both without pressure and under pressure are characterized by electron microscopy, and it is proved that large stresses and strains are generated at the micrometer scale. [ABSTRACT FROM AUTHOR]

At present, the influence of time-harmonic currents on the leakage flux coefficient of canned permanent magnet synchronous motors (CPMSMs) remains unclear. Therefore, this paper investigates and summarizes the effects of inverter time-harmonic currents on the leakage flux coefficient of the CPMSM. A 1.5 kW, 9000 RPM (Revolutions Per Minute) CPMSM is used as the research subject. Based on a finite element model, the leakage flux coefficients under sinusoidal and non-sinusoidal supply conditions are calculated using the magnetic flux density integration method. Additionally, the study examines changes in the leakage flux coefficient under different harmonic orders and amplitudes. The results indicate that the introduction of fifth and seventh time-harmonic currents by the inverter reduces the leakage flux coefficient, which helps to improve the utilization of the permanent magnets. This research significantly contributes to enriching the theory of inverter-fed permanent magnet motors. [ABSTRACT FROM AUTHOR]

High-k metal oxides are gradually replacing the traditional SiO2 dielectric layer in the new generation of electronic devices. In this paper, we report the production of five-element high entropy metal oxides (HEMOs) dielectric films by solution method and analyzed the role of each metal oxide in the system by characterizing the film properties. On this basis, we found optimal combination of (AlGaTiYZr)Ox with the best dielectric properties, exhibiting a low leakage current of 1.2 × 10−8 A/cm2 @1 MV/cm and a high dielectric constant, while the film's visible transmittance is more than 90%. Based on the results of factor analysis, we increased the dielectric constant up to 52.74 by increasing the proportion of TiO2 in the HEMOs and maintained a large optical bandgap (>5 eV). We prepared thin film transistors (TFTs) based on an (AlGaTiYZr)Ox dielectric layer and an InGaZnOx (IGZO) active layer, and the devices exhibit a mobility of 18.2 cm2/Vs, a threshold voltage (Vth) of −0.203 V, and an subthreshold swing (SS) of 0.288 V/dec, along with a minimal hysteresis, which suggests a good prospect of applying HEMOs to TFTs. It can be seen that the HEMOs dielectric films prepared based on the solution method can combine the advantages of various high-k dielectrics to obtain better film properties. Moreover, HEMOs dielectric films have the advantages of simple processing, low-temperature preparation, and low cost, which are expected to be widely used as dielectric layers in new flexible, transparent, and high-performance electronic devices in the future. [ABSTRACT FROM AUTHOR]

In this work, we show a high-performance GaN-on-Si quasi-vertical PiN diode based on the combination of beveled sidewall and fluorine plasma treatment (BSFP) by an inductively coupled plasma (ICP) system. The leakage current and breakdown voltage of the diode are systematically studied. Due to the beveled sidewall treated by the fluorine plasma, the diodes achieve an excellent breakdown voltage (VBR) of 790 V and a low reverse leakage current. In addition, the GaN-on-Si quasi-vertical PiN diode achieves a low specific on-resistance (Ron,sp) of 0.51 mΩ·cm2 and a high Baliga's figure of merit (BFOM) of 1.22 GW/cm2. The relationship between the total leakage current and the device diameter shows that the sidewall leakage is the main leakage path of the device. Afterwards, the TCAD simulations based on electric field and electric potential reveal that the fluorine plasma treatment is a major factor in suppressing the leakage current and increasing the VBR for a diode with BSFP. This work systematically analyzes the effects of beveled sidewall and fluorine plasma treatment based on the reverse characteristics of the GaN-on-Si quasi-vertical PiN diode and highlights the great potential of the GaN-on-Si PiN diode for various power applications. [ABSTRACT FROM AUTHOR]

Tunnel magnetoresistance (TMR) sensors, known for their high sensitivity, efficiency, and compact size, are ideal for detecting weak currents, particularly leakage currents in smart grids. However, temperature variations can negatively impact their accuracy. This work investigates the effects of temperature variations on measurement accuracy. We analyzed the operating principles and temperature characteristics of TMR sensors and proposed a high-precision, software-based temperature compensation method using cubic spline interpolation combined with polynomial regression and zero-point self-calibration. Additionally, a field-programmable gate array (FPGA)-based temperature compensation circuit was designed and implemented. An experimental platform was established to comprehensively evaluate the sensor's performance under various temperature conditions. Experimental results demonstrate that this method significantly enhances the sensor's temperature stability, reduces the sensitivity temperature drift coefficient, and improves zero-point drift stability, outperforming other compensation methods. After compensation, the sensor's measurement accuracy in complex temperature environments is substantially improved, enabling effective weak current detection in smart grids across diverse environments. [ABSTRACT FROM AUTHOR]

Transformerless grid‐connected inverters (GCIs) are universally utilized in the PV system. However, they have the shoot‐through issue and common mode leakage current (CMLC). To address the above‐mentioned issues, a transformerless common‐ground GCI without shoot‐through issue is proposed. The proposed topology has one common ground between the PV array and the grid that eliminates the CMLC. The topology is the combination of two buck‐boost converters, so it has the boost capability. Each buck‐boost converter operates in half‐line period, so the proposed inverter is a single‐stage system. Only two switches operate in high frequency in positive half‐line period and only one switch operates in high frequency in negative half‐line period. Therefore, efficiency of the system can be improved. There is no current flowing through the body diode of the MOSFET. Additionally, the presented inverter has no shoot‐through problem. The operating principle is elaborated. At last, simulation and experimental results of a 250 W proposed inverter validate the theoretical analysis. The maximum efficiency of the system is 96.2%. [ABSTRACT FROM AUTHOR]

In this letter, to improve the performance and reduce leakage currents of bulk low‐temperature multi‐layer SiGe/Si superlattice (SL) fin field‐effect transistors (FinFETs), a p‐type omega‐shaped channel (Ω‐channel) SL FinFET is realized by etching a Si/Si0.7Ge0.3 triple‐layer stacked structure in a replacement metal gate (RMG) module on a silicon‐on‐insulator (SOI) substrate. In addition, a self‐allied Ni0.9Pt0.1 silicide process and a low‐thermal‐budget (≤400°C) integration procedure were performed on the Ω‐channel SL FinFET. Test results demonstrate that the on‐state current (Ion) is increased by 5.5 times (from 78 to 429 µA/µm) and the off‐state current (Ioff) is reduced by 78.8% (from 5.2 × 10−3 to 1.1 × 10−3 µA/µm) when compared with the corresponding currents of traditional bulk SL FinFETs. [ABSTRACT FROM AUTHOR]

The polycrystalline Sr 0.8 Sn 0.2 Bi 1.75 Nd 0.25 Nb 2 O 9 (NdSBN) was synthesized using the green synthesis microwave sintering method, which significantly reduced the processing parameters of the NdSBN ceramics. Orthorhombic crystal structure with A2 1 am symmetry was revealed by Rietveld refinement study, whereas the doping-induced strain and crystallite size was studied using the Williamson Hall method. Crossectional SEM micrographs confirm the plate-like structure, with an average grain size of 273.7 nm. A diffuse type of phase transition was observed at 345 °C, which usually arises due to compositional fluctuations and mobile oxygen vacancies; further, the diffusiveness of the NdSBN was studied using Uchino and Nomura function, a modified version of Curie-Weiss law (CW). The frequency and temperature-dependent dielectric study of NdSBN ceramics display a Maxwell-Wagner relaxation with a high loss in a low frequency regime, possibly due to the presence of leakage current in the solid solution. Frequency dependent AC conductivity obeys Jonscher's power law, whereas DC conductivity supports polaron assisted hopping in NdSBN composition with dual activation energies of 0.55 eV and 0.75 eV, which correspond to electrons and ions, respectively. The non-Debye type relaxation mechanism in conjunction with negative temperature coefficient of resistance (NTCR) behavior was demonstrated by temperature dependent impedance spectroscopy, while modulus spectroscopy confirmed the multiple relaxation processes in NdSBN ceramics. [ABSTRACT FROM AUTHOR]

Controlling the formation of interfacial layers in dynamic random-access memory (DRAM) capacitors is crucial because it affects electrical performance, such as increasing the equivalent oxide thickness. This study investigates the formation of an interfacial layer during atomic layer deposition (ALD) of ZrO 2 on TiN electrodes and examines its influence on electrical properties. Utilizing O 3 and H 2 O as oxygen sources, we quantitatively identified notable differences in the formation of the interfacial TiO x layer. Using O 3 results in a thicker TiO x layer with fewer impurities, which lowers the leakage current, whereas H 2 O creates a thinner interfacial layer with higher impurity levels, leading to an increased leakage current. To optimize these effects, we developed a two-step ALD process that combines both oxygen sources, reducing the interfacial layer thickness while maintaining low leakage currents. This approach significantly improved the electrical performance of capacitors. Furthermore, similar results were observed for HfO 2 /TiN systems, suggesting that our findings are broadly applicable to high-k dielectric materials. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) benefits from high process temperatures when the substrate is not temperature-sensitive because the films deposited at higher temperatures exhibit better electrical properties. In this study, we investigated the ALD process of silicon oxide films by alternating injections of tris(dimethylamino)silane (tris-DMAS) and O 3 /O 2 at temperatures ranging from 400 to 700 °C. The saturation dose of tris-DMAS was 1.5 × 106 L at 400 °C. Self-limiting growth with a growth rate of approximately 0.9 Å/cycle was observed up to 600 °C, allowing excellent step coverage. However, at 700 °C, the growth rate increased significantly to 4.6 Å/cycle, carbon and nitrogen impurities were detected by secondary ion mass spectrometry, and step coverage was poor, supporting the thermal decomposition of tris-DMAS at this temperature. Therefore, the optimum temperature for ALD SiO 2 using tris-DMAS is 600 °C for application as an insulating film on high aspect ratio patterns. At this temperature, the leakage current density was 0.58 nA/cm2, and the oxide-trapped charge density was 4.0 × 1010 cm−2. [ABSTRACT FROM AUTHOR]

This work investigates the performance of state-of-the-art non-commercial 6.5 kV Silicon Carbide (SiC) PiN and Junction Barrier Schottky (JBS) diodes in hybrid (Si IGBT with SiC diode) and full SiC (SiC MOSFET with SiC diode) switch topologies. The static and dynamic performance has been systematically evaluated at distinct temperatures, gate resistances and currents for each configuration. The SiC PiN diode presented higher current density capability and lower leakage current density than the JBS diode. Moreover, in most cases, the SiC PiN diode-based topologies demonstrated slightly higher total switching losses compared to the SiC JBS diode-based equivalent configurations. A loadability analysis in a three-level NPC converter is presented to evaluate the potential of each configuration in a converter application. The SiC PiN technology presented a 25% power extension compared to the SiC JBS technology with similar efficiency at typical industrial drives switching frequency operation when comparing same-active-area diode technologies. Finally, a long-term reliability test (H3TRB) is presented to demonstrate the SiC PiN diode technology's potential for operation in harsh environments. Such characteristics show the advantage of the 6.5 kV SiC PiN diode when a high current density (>100 A/cm2), high efficiency and reliability are required. [ABSTRACT FROM AUTHOR]

This work investigates the gate oxide reliability of commercial 1.2 kV silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) with planar and trench gate structures. The performance of threshold voltage (V t h) and gate leakage current (I g s s) in SiC MOSFETs is evaluated under positive and negative gate voltage stress. The oxide lifetimes of SiC planar and trench MOSFETs at 150 °C are measured using constant voltage Time-Dependent Dielectric Breakdown (TDDB) testing. From the test results, it is found that electron trapping and hole trapping in S i O 2 caused by oxide electric field (E o x)  stress affect the V t h of SiC MOSFETs. The saturation and turnaround behavior of the V t h shift during positive and negative gate voltage stresses indicates that the influence of charge trapping in the gate oxide varies with stress time. The I g s s under positive and negative gate voltages depends on the tunneling barrier height for electrons and holes, respectively, which can be calculated using the Fowler–Nordheim (FN) tunneling mechanism. Moreover, the presence of near-interface traps (NITs) affects the barrier height for holes under negative gate voltages. The behavior of V t h shift and I g s s under high-temperature gate bias reflects the charge trapping occurring in different regions of the gate oxide. In addition, compared to SiC planar MOSFETs, SiC trench MOSFETs with thicker gate oxide tend to exhibit higher lifetimes in TDDB tests. [ABSTRACT FROM AUTHOR]

The ferroelectric switching behavior of a metal–ferroelectric AlScN–HfO2 interlayer–metal (MFIM) capacitor was investigated at variable temperatures and compared with an MFM capacitor. Although the MFIM capacitor demonstrated an inferior remnant polarization (2Pr value of 74 µC/cm2), it exhibited a reduced leakage current (×1/100) and higher breakdown field. The MFIM showed a stable change in 2Pr from room temperature to 200 °C and an enhanced endurance of ~104 cycles at 200 °C; moreover, the leakage current was less degraded after the cycling tests. Thus, the ferroelectric AlScN with a thin HfO2 interlayer can enhance the reliability of ferroelectric switching. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) metal-oxide semiconductor field-effect transistors (MOSFETs), as a new material, have the advantages of low drain-source resistance, high thermal conductivity, low leakage current, and high switching frequency compared with silicon (Si)-based MOSFETs. Therefore, in many industrial applications, Si MOSFETs have been replaced by SiC MOSFETs. However, as the switching speed increases exponentially, some problems are amplified, the most serious of which is the overshoot of current and voltage. The increase in voltage and current slope caused by high switching speeds inevitably leads to overshoot, oscillations, and additional losses in the circuit. This paper focusses on the actual performance of the optimised switching strategy (OSS) in circuit testing and combines the existing simulation results to verify the practicability of OSS. In this paper, the optimised switching strategy is introduced first, and then, the LTspice model of SiC MOSFET is established in detail and verifies the feasibility of the OSS through half-bridge circuit simulation. Finally, the test platform is built using a programmable gate drive module (2ASC-12A1HP). Through a 400 V/30 A double-pulse test, the practicality of the OSS is verified. The experiments show that the OSS can greatly improve the switching performance of SiC MOSFETs. [ABSTRACT FROM AUTHOR]

Ferroelectric properties of HfO 2 -based films are reported to be largely influenced by various factors including stress, grain size and oxygen vacancies. In this study, Hf 0.5 Zr 0.5 O 2 (HZO) films were deposited directly on Ti bottom electrode (Ti-BEs). The polarization switching behavior and fatigue performance exhibited notable distinctions as a result of varying oxygen vacancies in the films upon annealing under different atmosphere of N 2 , air and O 2 with different annealing time. The HZO film after being annealed in air demonstrated a comparatively larger remnant polarization (P r) value of 20.4 μC/cm2 and superior fatigue performance over 108 field cycles. Furthermore, the internal mechanisms were analyzed through density functional theory (DFT) calculations. The introduction of more oxygen vacancies was observed to reduce the formation energy of o -phase and promote the enhancement of ferroelectricity. However, it should be noted that this also resulted in an increase of leakage current. Therefore, it is crucial to carefully control the concentration of oxygen vacancies, considering the overall impact on both the reliability and ferroelectricity of thin films. The results of this work can provide an effective pathway to grow HZO ferroelectric films with high performance through the control of oxygen vacancies concentration. [ABSTRACT FROM AUTHOR]

High-entropy materials constitute solid solutions composed of five or more elements. This complex and diverse composition endows the materials with unique physical and chemical properties, presenting immeasurable value in material design. Despite such potential applications, the composition design still has deficiencies, and the influence mechanism of elements remains a research gap. In this work, a series of new high-entropy perovskites (La 0.5 X 0.5) 0.2 (Ce 0.5 X 0.5) 0.2 Ba 0.2 Sr 0.2 Ca 0.2 TiO 3 (where X = Li, Na, K) were designed and synthesized. We systematically studied their phase structures, microscopic morphologies, as well as dielectric and ferroelectric properties. Notably, novel findings are reported. Specifically, (La 0.5 Li 0.5) 0.2 (Ce 0.5 Li 0.5) 0.2 Ba 0.2 Sr 0.2 Ca 0.2 TiO 3 ceramics exhibit excellent breakdown field strength (E b = 135 kV cm−1) and minimal leakage currents in 10−7–10−6 A cm−2. Moreover, the designed ceramics display exceptional dielectric constant (ε r = 5 × 104) and saturation polarization (P s = 2.8 μC cm−2) properties. These findings introduce novel insights into designing high-entropy ceramic components, enabling the customization of new dielectric and ferroelectric properties by manipulating doped monovalent ions. [ABSTRACT FROM AUTHOR]

Herein, a core–shell structured nanocomposite with excellent electrorheological (ER) properties was successfully prepared for studying ER fluids (ERFs). First, the material was prepared by using chromium (Cr)-ion-doped Ti-based metal–organic frameworks (MOF-Ti) as a template using the solvothermal method, followed by coating with SiO 2 via hydrolysis to form Cr-MOF-Ti/SiO 2 composite. In combination with the advantages of the MOF-Ti structure, such as more active sites and a high specific surface area, doping with transition metal ions and coating with SiO 2 can effectively enhance the interfacial polarisation of the obtained Cr-MOF-Ti/SiO 2 composite and thus improve its ER performance. Analyses were conducted on the morphology, elemental composition and functional groups of the materials using scanning electron microscopy, transmission electron microscopy, X-ray diffractometer, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller and dielectric analysis. The results indicate successful Cr-ion doping and SiO 2 coating. The ER performance of the composite particles was also evaluated. The results indicate that the SiO 2 -coated sample exhibits superior ER properties, including a smaller leakage current density and higher shear stress. Moreover, the SiO 2 coating enhanced the interfacial polarisation capability of Cr-MOF-Ti, as verified by the dielectric data. [ABSTRACT FROM AUTHOR]

Perhydropolysilazane (PHPS), which contains no organic catalyst, chemically reacts with H2O in the atmosphere by heating it at 450 °C for more than 1 h to turn it into a SiO2 film. If silica conversion can be achieved at temperatures below 100 °C, which plastics can withstand, it may be applicable to a wide range of applications, such as flexible electronics. Here, we report a technique for forming SiO2 films with leakage current characteristics very close to those of thermally oxidized (THOX) films that works at a very low temperature of 52 °C with high speed. Using a 9-kV, 30-kHz power supply, a low-temperature plasma jet containing a gas mixture of Ar and water vapor irradiated an 8 nm thick PHPS thin film, inducing silica conversion at a maximum substrate temperature of 52 °C. The current density-electric field strength (J-E) characteristics of metal oxide semiconductor capacitors fabricated with this SiO2 film showed characteristics very close to those of THOX films. In addition, the mechanism of silica conversion of PHPS through low-temperature plasma jet irradiation using this gas mixture was clarified in real-time FT-IR measurements. [ABSTRACT FROM AUTHOR]

Spinal cerebrospinal fluid (CSF) leaks can be caused by tears in the dura and are challenging to treat. Traditional methods of treating spinal CSF leakage include nonsurgical management, epidural blood patches (EBP), and direct surgical repair. Minimally invasive surgery (MIS) is rapidly progressing within neurosurgery due to its advantages for patient safety and comfort. Existing MIS techniques to spine surgery utilize a rigid endoscope, which has limitations when reaching smaller areas requiring greater degrees of visualization. The simultaneous use of a flexible endoscope and wearable heads-up display (wHUD) improves access and visualization in these small areas while allowing the surgeon to maintain optimal ergonomics. In this article, we review minimally invasive approaches to spine surgery and the management of spinal CSF leaks. We also demonstrate a novel minimally invasive technique utilizing flexible endoscopy and a wHUD to treat a case of recurrent CSF leak. We describe the successful utilization of this technology and provide the groundwork for future practitioners to incorporate this approach into their practice. [ABSTRACT FROM AUTHOR]

ZnO thin films were deposited using RF sputtering by varying the argon:oxygen gas flow rates and substrate temperatures. Structural, optical and electrical characterization of ZnO thin films were systematically carried out using X-Ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible spectroscopy, X-Ray photoelectron spectroscopy (XPS) and Hall measurements. Film deposited at room temperature and annealed at 300 °C exhibited low O2 incorporation with localized defects and a high percentage of Zn interstitials. A large crystalline size and fewer grain boundaries resulted in a high Hall mobility of 46.09 cm2/V-s Deposition at higher substrate temperatures resulted in improvement in O2 incorporation through the annihilation of localized defects and decrease in oxygen vacancies and Zn interstitials. Urbach tails within the bandgap were identified using the absorption spectrum and compared with the % defects from XPS. Bottom-gate thin-film transistors were subsequently fabricated on a SiO2/p-Si substrate using the combination of RF sputtering, wet etching and photolithography. Variation in the substrate temperature showed performance enhancement in terms of the leakage current, threshold voltage, sub-threshold swing and ION/IOFF ratio. Thin-film transistor (TFT) devices deposited at 300 °C resulted in an O2-rich surface through chemisorption, which led to a reduction in the leakage current of up to 10−12 A and a 10-fold reduction in the sub-threshold swing (SS) from 30 V to 2.8 V. Further TFT optimization was carried out by reducing the ZnO thickness to 50 nm, which resulted in a field-effect mobility of 1.1 cm2/V-s and ION/IOFF ratio of 105. [ABSTRACT FROM AUTHOR]

In this study, the effects of Al2O3 and Y2O3 passivation layers on Ge substrates are investigated to enhance the thermal stability of Ge-based devices. Using X-ray photoelectron spectroscopy, we analyze the growth characteristics and chemical composition of Al2O3, Y2O3, and ZrO2 on Ge. The changes in the crystallinity of ZrO2 on different substrates of Ge, Al2O3/Ge, and Y2O3/Ge configurations are observed via X-ray diffraction. Material properties, including capacitance, flat band voltage shift (ΔVFB), oxide charge trap (Not), interface defect density (Dit), and leakage current, are analyzed using the metal–oxide–semiconductor capacitor, with a particular focus on their electrical characteristics. Additionally, we investigate whether the passivation mechanisms of each material are more suitable for enhancing thermal stability. Overall, this study provides insight into the role of passivation layers in improving the interface and thermal stability of Ge-based devices, offering valuable contributions to the advancement of semiconductor technology. [ABSTRACT FROM AUTHOR]

The long-term operation performance of HVDC transmission systems is significantly influenced by the reliability of thyristors. However, the current reliability research of thyristors is mainly based on the leakage current and there is no comprehensive degradation characteristics of thyristors. In this article, the degradation characteristics of thyristors under voltage and temperature accelerated ageing tests are obtained, including the reverse recovery characteristic, on-state characteristic, blocking characteristic and gate characteristic. The reverse recovery characteristic obviously degrades under the voltage accelerated ageing tests. The reverse recovery charge and reverse recovery time decrease by over 10% after the tests. Seven thyristors operating for a certain number of years from two HVDC stations are tested, and the results verify the thyristor degradation characteristics obtained from the ageing tests. Moreover, the mechanisms of the leakage current and reverse recovery characteristic are analyzed in detail. [ABSTRACT FROM AUTHOR]

The lead-free piezoelectric ceramics (1- x)Bi 3 TiTaO 9 – x Na 0.5 Bi 2.5 Nb 2 O 9 [(1- x)BTT– x NBN; x = 0.0; 0.2; 0.5; 0.7; 1.0] were prepared using the traditional solid-state method, and the microstructure and electrical properties of the novel solid solution (1- x)BTT– x NBN were studied. XRD data and Raman spectroscopy analysis indicated that Na ions and Nb ions had been incorporated into the designed lattice, forming a stable solid solution. The piezoelectric performance of the (1- x)BTT– x NBN ceramics was improved for two reasons: on one hand, the incorporation of NBN could suppress the leakage current caused by Ti ions, effectively reducing the contribution of oxygen vacancies to the direct current resistivity, thereby increasing the ceramic's direct current resistivity (ρ dc); on the other hand, the orthorhombic distortion was reduced, and the remanent polarization was enhanced. Among them, the 0.3Bi 3 TiTaO 9 -0.7Na 0.5 Bi 2.5 Nb 2 O 9 ceramic demonstrated excellent comprehensive performance: the values of d 33 , T c , and P r were 14.4 pC/N, 777.8 °C, and 9.82 μC/cm2, respectively. Specifically, at 500 °C, tan δ and ρ dc were 0.67 % and 1.01 × 108 Ω∙cm, respectively, and after depolarization at 750 °C, its d 33 remained at 97.92 % of the original value. [ABSTRACT FROM AUTHOR]

Pristine HfO 2 tends to have a monoclinic phase with a low dielectric constant. Reportedly, yttrium(Y) doping has been used to induce the tetragonal phase in HfO 2 , with Y contributing to the formation of the tetragonal phase and improving the crystallinity. However, Y doping in HfO 2 forms oxygen vacancies, resulting in a relatively high leakage current. Owing to the difficulty in suppressing the oxygen vacancies crucial for inducing the tetragonal phase, we focused on another significant leakage current path: the grain boundary. Introducing a heterostructure is expected to reduce the grain size and mitigate the leakage current by increasing the length of the leakage path. This study compares the dielectric constant and leakage current based on the stacking sequence of ZrO 2 and Y-doped HfO 2 (Y-HfO 2) and elucidate the underlying differences through electrical analysis. Additionally, crystallographic analysis reveals the reasons for the structural order-dependent variations in the electrical properties. Finally, the structure with a Y-HfO 2 layer at the bottom demonstrates advantages in achieving a lower leakage current. [ABSTRACT FROM AUTHOR]

Advanced filamentary devices are crucial for developing low‐power devices to implement high‐speed logic and neuromorphic devices. Among these, HfO2‐based filamentary devices have attracted attention as viable options due to their threshold‐switching characteristics and compatibility with complementary metal‐oxide‐semiconductor (CMOS) technology. However, the unpredictability of conventional filament formation/rupture driven by an electric field challenges consistency and reliability. A paradigm shift from conventional stochastic electric field‐driven ion migration to controllable ion‐based transportation is essential to devise functional low‐power devices capable of controlling the filament process. This work introduces a magnetic field‐assisted threshold switching (MA‐TS) device, which integrates a neodymium magnet and a nickel (Ni) barrier layer to enable controlled dual field‐driven ion transportation. The dual field‐driven process combining the conventional vertical electric field‐driven ion migration with lateral magnetic field‐driven ion transportation, reveals a distinctive aspect of ion movement. The MA‐TS device achieves superior performances characterized by an ultra‐low threshold voltage (≈0 V), minimized leakage current in the off‐state, a variation‐immune hysteresis‐free characteristic, enhanced yield, and revival‐ability (i.e., self‐healing) after a failed TS operation. By overcoming the limitations of conventional filamentary devices, the MA‐TS device opens up a promising avenue for efficient and stable low‐power applications. [ABSTRACT FROM AUTHOR]