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Ceramic saggars of mullite‐cordierite are currently used to produce cathode powders for lithium‐ion batteries. Strong interactions occur between the LiNi0.8Mn0.1Co0.1O2 (NMC) precursor in the temperature range of calcination (750–1000°C) leading to corrosion and formation of cracks in the saggar. The frequent failure of saggar causes a lot of waste, which could be reduced by choosing corrosion‐resistant materials. To understand the corrosion mechanism in the system MgO–Al2O3–SiO2, the materials MgO, Al2O3, MgAl2O4, and SiC (instead of SiO2) were embedded in premixed NMC precursor and calcined at T = 780°C for 50, 100, 150 and 200 h. The formed phases were determined by phase and microstructure analysis. Finally, the formation of LiAlO2 and Li5AlO4 is associated with a lower growth rate of the corrosion layer compared with Li4SiO4, while MgO is inert. The reactivity with NMC can be ordered as follows: SiO2 > Al2O3 > MgO. [ABSTRACT FROM AUTHOR]

Vat photopolymerization (VPP) printing of ceramic parts offers advantages such as low cost, simple operation, and short fabrication cycles. However, drawbacks include low toughness and brittleness in the printed parts. This study explores enhancing the toughness and strength of alumina (Al2O3) ceramics by incorporating silicon carbide (SiC) particles as additives. The impact of varying SiC contents on the quality of VPP‐printed Al2O3 parts is examined, encompassing microstructure, physical properties, and mechanical properties. Results indicate that optimal SiC addition reduces Al2O3 ceramics' porosity, enhances crystalline quality, and boosts mechanical properties. Excessive SiC, however, diminishes these benefits. The most significant strengthening of Al2O3 parts occurred with a 1.5 wt.% SiC content, increasing bending strength and fracture toughness by 239.7% and 564.7%, respectively. This underscore SiC's positive role in enhancing the quality of VPP‐printed Al2O3 parts. [ABSTRACT FROM AUTHOR]

The structural integrity of continuous carbon fiber‐reinforced silicon carbide (Cf/SiC) composites is often compromised by carbon fiber damage during high‐temperature sintering, nonuniform fiber distribution, and the brittleness of the ceramic matrix, which limits their broader application. This study reported an innovative approach of vacuum bagging combined with thermal press curing, followed by precursor infiltration and pyrolysis (PIP) and reaction melt infiltration (RMI), densification to fabricate a Cf/SiC composite with remarkable properties. The pyrolytic carbon (PyC)/boron nitride (BN) double interface layers were deposited to the Cf via chemical vapor deposition (CVD). Results revealed that vacuum bagging combined with thermal press curing effectively eliminated bond‐line defects, while the PyC/BN interface layer further improved the toughening of Cf. The combination of vacuum bagging and thermal press curing showed optimal strength of 330 ± 30 MPa and 7.4 ± 0.5 MPa m1/2, representing increases of 50% and 47%, respectively. The failure mechanisms responsible for the mechanical behavior are gained through macro and microanalysis. This work provides a high‐performance, economical, and convenient process for enhancing the mechanical performance of Cf/SiC composites, providing valuable insights for the development of ceramic matrix composites. [ABSTRACT FROM AUTHOR]

Electron irradiation‐induced acceleration of self‐healing and high‐temperature oxidation has been discovered in SiC/Y2Si2O7–Y2SiO5 composites. Bulk samples were produced by pulsed electric current sintering. These samples were exposed to an electron beam from the pulsed intense relativistic electron beam accelerator with a beam energy of 2 MeV at irradiation doses of 10–40 kGy. The self‐healing and high‐temperature oxidation experiments were carried out at 1100–1300°C for 1–24 h in laboratory air. Electron irradiation significantly improved the self‐healing effectiveness. The closure of surface cracks was caused by the volume expansion of SiC via transformation to SiO2 and the outward diffusion of Y3+ ions. Electron irradiation also increased the thickness of the internally oxidized zone, formed by the inward diffusion of O2− ions. Enhanced self‐healing and oxidation behavior were associated with defect formation induced by electron beam exposure, which facilitated the diffusion of ions within the crystal lattice. [ABSTRACT FROM AUTHOR]

Porous silicon carbide ceramics are ideal candidates for filters, separation membranes, and high‐temperature structural materials, for which high porosity and precise pore size control are required. However, high porosity and large pore sizes usually lead to degradation in mechanical properties. In this work, silicon carbide powder with two different particle sizes was used as the raw material, and C powder and SiO2 powder were used as pore‐forming agents. A series of pure silicon carbide porous ceramics with micron‐sized pores were prepared by recrystallization sintering. The porosity and pore size of obtained samples were controllable and adjustable, and the mechanical properties were significantly enhanced. The microstructure, pore size distribution, porosity, and crystal phase of silicon carbide porous ceramics were characterized by scanning electron microscope, pore size analyzer, Archimedes method, and X‐ray diffraction. The effect of adding C/SiO2 on the porosity, the pore size, and the micro‐morphology of sintering samples was studied. The results show that C/SiO2 can adjust the porosity and pore size of pure silicon carbide porous ceramics in a wide range. The highest porosity of the obtained sample adding 40% C/SiO2 was up to 64.42%, and the average and maximum aperture are 5.42 and 11.98 µm, respectively. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) can form many different polytypes but their energetic ordering and frequency of occurrence are still not fully understood. In this study, polytype stability in pure and doped SiC as well as charged defects are studied by first‐principle calculations. The dopants under investigation include N and Al which are added as single dopants and also as dopant pairs. Regarding pure SiC, our findings align with previous works which have shown that energy differences between polytypes are smaller than uncertainties related to the choice of exchange‐correlation functional. In contrast, the effects of doping are predicted consistently for different xc functionals with N doping leading to a stabilization of the 3C polytype while Al doping causes only minor changes. This effect is explained based on the differences in the band‐gap of the polytypes and the dopant‐induced defect states in agreement with an explanation suggested by Heine et al (J Am Ceram Soc. 1991;74(10):263033). We further corroborate this explanation with calculations of charged dopants. As a consequence, Al in proximity to N can entirely neutralize the donor and its stabilization effect on 3C. Furthermore, a strong attraction (1.8–1.9 eVs) is observed between the two dopants which indicates that they will occur in pairs. Our results provide a more complete picture of SiC doping and we discuss its implications for the crystal growth process. [ABSTRACT FROM AUTHOR]

This study systematically explores the wetting characteristics of re‐entrant microstructures, focusing on the interplay between the unique geometries and material compositions. While silicon dioxide (SiO₂) re‐entrant microstructures are previously studied, this research pioneers the fabrication of silicon carbide (SiC) re‐entrant microstructures. Through experimental approaches and theoretical analysis, the research assesses how variations in geometry and material impact wettability. Key findings reveal that SiC re‐entrant structures achieve an average contact angle of 145°, closely matching the 148° observed for SiO₂, indicating similar hydrophobic behavior. Although flat SiC surfaces exhibit higher inherent hydrophobicity than flat SiO₂ (59° vs 26° contact angle), re‐entrant geometry predominantly influences wetting behavior, overshadowing material differences. Structures with lower solid area fractions show increased hydrophobicity, with a distinct hierarchy: microlines are the least hydrophobic, followed by shark‐skin textures, rectangles, circles, and triangles. Additionally, increasing the gap size between structures enhanced hydrophobicity up to a critical point. This study paves the way for optimizing re‐entrant microstructures for specific applications, significantly enhancing the understanding of surface science and advancing material design. [ABSTRACT FROM AUTHOR]

In this report, the advanced manufacturing advantages of using supersaturated chlorinated chemistry are demonstrated at 1550 °C in 4H‐silicon carbide (4H‐SiC) epitaxy on trenches with different geometric profiles. Sloped mesa sidewalls (8°) show improved filling behavior compared with vertical sidewalls (2°) and lower the optimum chlorine/silicon ratio (Si:Cl) required to complete filling. Both the optimum Cl:Si ratio (10) and sidewall angle are lower for wider trench openings, allowing complete fill of 3 µm wide trenches (8 µm pitch, 5 µm depth) at a filling rate of 19 µm h−1. Excessive hydrogen chloride (HCl) diminishes filling by reducing sidewall growth and can also produce an end surface with very rough topography. This work demonstrates the importance of trench geometry on both the filling behavior and process optimization in chlorinated trench filling epitaxy for the manufacture of 4H‐SiC superjunction power electronics. [ABSTRACT FROM AUTHOR]

ABSTRACT Three‐phase brushless DC (BLDC) motors are cost‐effective and are increasingly used in various speed control applications. The phase voltage, DC‐bus utilization, current ripple, and torque ripple are major performance parameters for a BLDC motor drive. Different pulse width modulation (PWM) methods will diversely influence these parameters. This paper presents the phase voltage, current ripple, and DC‐bus utilization analysis of BLDC motor drive for four PWM techniques and provides a comparative analysis. The current ripple of the BLDC drive is evaluated with low and high switching frequency operations. Phase voltage and DC‐bus utilization of a BLDC motor are evaluated using analytical methods and validated experimentally. The investigation provided in this work are significant for PWM selection and implementation for low and high switching frequency operations. Both low‐ and high‐frequency operations are performed by supplying the BLDC drive from a silicon carbide (SiC) based inverter. These PWM techniques are also compared, considering high and low‐speed applications. Experimental results of SiC inverter‐fed BLDC motor drive are provided to substantiate the proposed work. [ABSTRACT FROM AUTHOR]

In this paper, highly electrically and thermally conductive copper powders (Cu) and electrically insulative yet thermally conductive silicon carbide whiskers (SiCw) were selected as functional fillers and high‐density polyethylene (HDPE) was used as the matrix to prepare thermal conductive composites. By controlling the amount of Cu at 30 vol% which is below percolation threshold, the volume resistivity of the composites is maintained above 1014 Ω cm. The results showed that SiCws entered the area which was not occupied by Cu particles and they played a bridging effect among Cu particles, thereby promoting the formation of intact thermal conductive pathways that contributed to improving the thermal conductivity of corresponding composites. The combination of SiCw:Cu = 3:1 at a filler content of 30 vol% resulted in a thermal conductivity as high as 1.921 W/mK, which is 380% higher than pure HDPE. [ABSTRACT FROM AUTHOR]

Particle grading is a reliable method to improve mechanical properties of reaction‐bonded silicon carbide (RBSC) ceramics. This work aims to explore the effects of particle grading on thermal and mechanical characteristics of RBSC ceramics. Results showed that the powder grading enabled to increase sintering density of silicon carbide (SiC) ceramics. The use of large particle SiC powder in grading led to a 28% increase in thermal conductivity but a 22% decrease in bending strength. Meanwhile, the addition of finer SiC powder exerted minimal effect on thermal conductivity but noticeably increased bending strength by 10%. Therefore, properly adjusting particle size in grading allows for the control of residual Si content and microstructure, thereby simultaneously increasing thermal conductivity and bending strength of the material. [ABSTRACT FROM AUTHOR]

A new preparation process for silicon carbide (SiC) powder is developed. In the Si–(C) –PTFE–Ar system, the grain size and morphology of the product 3C–SiC were controlled by adding a carbon source (graphite) and changing the percentage of polytetrafluoroethylene (PTFE) (0%, 10%, and 20%). The experimental results showed that the SiC powders prepared using a molar ratio of 1:1 silicon powder to graphite, plus 20% PTFE have a uniform particle size distribution (∼130 nm), a lamellar structure made of spherical particle stacking, a small bandgap (1.80 eV), a high carrier concentration, and a large number of lattice defects. These properties are expected to increase the electrical conductivity of 3C–SiC and decrease its thermal conductivity, thus providing a promising feedstock preparation option for SiC thermoelectric materials. In addition, the mechanism of PTFE in the preparation of SiC reactions was studied in detail. [ABSTRACT FROM AUTHOR]

The current study focuses on the role of composition in the oxidation behavior of three commercial SiC fibers (Hi‐Nicalon Type S (HNS), Tyranno ZMI, and Tyranno SA) in a steam‐containing environment at 1000°C. Oxide scales that form on each of the three fiber types differ in morphology, microstructure, and composition. Differences are attributed to O and C contents, crystallinity, and minor alloying elements. Oxidation kinetics of the HNS fibers follow linear/parabolic (Deal–Grove) predictions over the entire range of exposure times (to 96 h). In the other fibers, deviations from the initial linear/parabolic trend occur when either the scale crystallizes in situ during oxidation (as on the ZMI fibers) or when structural changes internal to the fiber alter the chemical environment at the scale/fiber interface (on the SA fibers). Adaptations of the linear/parabolic oxidation model are used to rationalize the growth kinetics in the latter two cases. Collectively, the data and analyses indicate a two‐fold difference in permeabilities of crystalline and amorphous silica scales. Inferred interface reaction rates further suggest faster oxidation for fibers with greater amounts of amorphous Si–O–C. Moreover, crystalline scales are more prone to cracking, because of their higher viscosity at elevated temperatures and a deleterious phase transformation upon cooling. [ABSTRACT FROM AUTHOR]

Tristructural isotropic (TRISO) fuel particles, developed for use in high‐temperature gas‐cooled nuclear reactors, can be subjected to oxidizing environments in off‐normal accident scenarios. In this study, surrogate TRISO fuel particles were oxidized at 1000–1350°C for 4 h in 20 kPa water vapor atmosphere balanced with ultrahigh‐purity helium gas. The oxide scale morphology and thickness were studied via scanning electron microscopy, focused ion beam, and transmission electron microscopy. The oxide thickness increased as the oxidation temperature was increased. Although the oxide scale at 1000°C was completely amorphous, pockets of crystalline oxide were observed on particles oxidized at 1200 and 1300°C. Kinetic analysis was performed to deduce the oxidation mechanism by determining the apparent activation energy using linear regression analysis. The oxidation mechanism was consistent for temperatures from 1000 to 1200°C with an activation energy of 412.4 ± 8.8 kJ/mol. The activation energy then dropped to approximately 201 ± 7.1 kJ/mol for temperatures 1200–1350°C. Therefore, there is a change in oxidation mechanism at ∼1200°C. This change is attributed to the existence of a network of significant bubbles in the oxide layer at higher temperatures, which serve as rapid diffusion pathways for the transport of oxidants from the surface to the SiC/SiO2 interface, instead of relying on the bulk diffusion through the SiO2 layer at lower temperatures where only small bubbles are present along the SiC/SiO2 interface. [ABSTRACT FROM AUTHOR]

Highlights Silicon carbide (SiC)‐resin composites with porous structures exhibit excellent energy absorption characteristics. In this study, three types of triply periodic minimal surface (TPMS) structures (Schwarz primitive, Schwarz diamond, and Schwarz I‐graph‐wrapped (IWP)) were fabricated using the digital light processing (DLP) technique. Under static compression, the TPMS structures mainly fracture at the four ends of the X crossband. The SiC‐reinforced resin exhibited superior specific energy absorption in quasistatic compression performance compared with the same structure constructed of metal at the same density. Moreover, the transient impacts under dynamic strain rates did not cause significant irregular or asymmetric shear damage to the structure. The dynamic energy absorption of SiC‐reinforced resin with a primitive structure was relatively superior to that of the IWP and diamond structures. Therefore, the TPMS structure of the 5 wt.% SiC‐resin composite possesses significant energy absorption characteristics and can be extended for applications in aerospace. SiC reinforced resin exhibits superior specific absorption energy in quasi‐static compression performance. The yield strength of the static compression of the primitive structure is averaging nearly 17 MPa. The dynamic energy absorption of SiC reinforced resin with primitive structure is relatively superior between 65.68 and 71.63 J/g. The TPMS structure of 5 wt.% SiC/resin possesses significant energy absorption characteristics. [ABSTRACT FROM AUTHOR]

The main objective of this investigation is the consolidation and flexural strength of alpha silicon carbide ceramics produced without additives by spark plasma sintering. Using the design of the experiment method, we optimized temperature and dwell to achieve fully dense silicon carbide bulks. The consolidation process of silicon carbide was analyzed similarly to the creep of bulk ceramics, and it was determined that the activation energy for the densification process was 596 ± 39 kJ/mol, while the stress exponent n was below 2. Bulk additive‐free silicon carbide ceramics gradually increased flexural strength as the temperature rose to 2000°C. The flexural strength at 2000°C was influenced by the loading rate, and under 2.5 mm/min, it reached a maximum of 2.08 GPa. To explain this phenomenon, a deformation mechanisms map was created, indicating that diffusion creep is the most probable mechanism for the strain sensitivity of SiC at 2000°C. Transmission electron microscopy indicated a substantial rise in twin density within the α‐SiC grains at 2000°C, indicating the activation of a previously unreported self‐reinforcing mechanism. [ABSTRACT FROM AUTHOR]

A quasi‐vertical gallium nitride (GaN) fin field effect transistor (FinFET) is designed and analyzed to assess the performance of electrical parameters. The device is deployed on a silicon carbide (SiC) substrate and analyzed using technology computer‐aided design (TCAD). The donor concentration in the critical regions is identified as a significant limiting factor for FinFET electrical properties. Hence, the influence of channel and drift layer doping concentrations (Nd) on performance characteristics is investigated in this work. The electrical characteristics such as threshold voltage, ION/IOFF ratio, subthreshold swing (SS), specific ON‐resistance, and breakdown voltage (VBV) are evaluated for various doping profiles. The doping profile with channel and drift layer concentration of 4 × 1015 cm−3 for a 300 nm fin width and 1 μm thick drift layer exhibits normally OFF behavior with a threshold voltage (Vt) of 1.5 V. It also demonstrates a VBV of 139 V. The corresponding doping profile reveals a low SS of 61 mV dec−1, which is comparable to other similar power devices. This demonstrates the significant potential of the device for medium‐power switching applications. [ABSTRACT FROM AUTHOR]

Hierarchical porous silicon carbide (SiC) ceramics were fabricated by combining particle‐stabilized emulsions and three‐dimensional (3D) printing. Direct ink writing (DIW) was used as the 3D printing technique. The formulation for successful printing is discussed in relation to the rheology of the emulsions. The SiC emulsions were able to be printed with a lower storage modulus (G′) and apparent yield shear stress (τy) than previously reported SiC ink pastes. The printed and sintered porous SiC ceramics possess a total porosity of 73.7% with an average pore size within the filaments of 2.2 µm in diameter. A hierarchical pore structure that contains pore sizes of about 250 µm, around 1–10 µm and smaller than 0.5 µm can be observed in the microstructure and pore size distribution. The mechanical properties showed a good strength‐to‐density ratio, and the thermal conductivity was reduced to 4.9 W/m·K. This study provides a new reliable approach for fabricating hierarchical porous SiC ceramics with low thermal conductivity. [ABSTRACT FROM AUTHOR]

Over the past years, nanostructured metalenses with thin form factors have been extensively studied for their potential in consumer and industrial applications. Despite significant advancements, current metalenses struggle to achieve high numerical aperture (NA), manufacturable structures, broad working bandwidth, and extended depth of focus (DOF) simultaneously. This paper introduces a comprehensive inverse design framework that facilitates the rapid development of polarization‐insensitive 3D metalenses, effective in both frequency and spatial domains. The framework employs shape‐constrained topology optimization to define horizontal ring profiles, along with discrete particle swarm optimization to manage discretized ring heights. Two immersed silicon carbide metalenses are demonstrated to showcase this framework's capability, providing near‐unity NAs for enhanced photon collection. The first design is an extended DOF metalens, exhibiting a DOF over four times the light wavelength and achieving a maximum diffraction efficiency of 23%, close to the theoretical limit. The second design achieves broadband achromaticity, suppressing chromatic aberrations across a wide 300 nm bandwidth (850–1150 nm) while maintaining an average diffraction efficiency of 10%. This methodology serves as a valuable tool for deploying functional metalenses with implications for nanophotonics, quantum optics, and quantum nanotechnology. [ABSTRACT FROM AUTHOR]

Dielectric elastomers (DEs), have attracted interest because they can replicate the behavior of muscles. They can change shape when subjected to an electric field. A novel DE is proposed in this study that incorporates silicon carbide (SiC) nanowires into silicone rubber (SR). The nanowires were propagated using polycarbosilane via a chemical vapor reaction (CVR). A boronate polymer was employed to promote compatibility between SR and SiC nanowires which modified the nanowire surfaces, leveraging a strong adhesive quality of the catechol moiety. Electrohydrodynamic (EHD) inkjet printing was then used to form the DEs into various shapes. These DEs had substantial dielectric constants of the order of 4.46. Significantly, one of the DEs achieved the highest actuated area strain of 20.36% in an electric field of 16.5 V/μm, demonstrating excellent driving performance. Furthermore, when used the fabricated DEs showed pronounced long‐term stability, meaning they are capable of finding applications in artificial intelligence, biomimetics, aerospace, and other disciplines. Highlights: The SiC nanowires were obtained through a chemical vapor reaction.A boronate polymer with catechol moiety was used to modify the SiC nanowires.DEs were formed various shapes by inkjet printing.DEs achieved very large actuated strains of up to 20.36% at 16.5 V/μm. [ABSTRACT FROM AUTHOR]

This study aims to enhance the properties of biodegradable plastics by blending poly(lactic acid) (PLA) as well as poly(butylene succinate) (PBS) with silicon carbide (SiC). SiC content was varied from 10 to 40 phr using an internal mixer, maintaining a 90/10 wt% ratio of PLA/PBS as the matrix. The investigation covered mechanical, thermal properties, chemical structure, and composite morphology. The morphological analysis confirmed even dispersion of SiC within the PLA/PBS matrix, possibly due to improved compatibility via a silane coupling treatment. This resulted in the maximum Young's modulus and impact strength with 40 phr SiC, showing a 40% and 76% enhancement, respectively, compared to pure PLA. Concerning thermal properties, SiC addition influenced the mobility of PLA/PBS molecular chains and crystalline structure, leading to an increase in Tg with higher SiC fractions. However, ΔHm of PLA, PBS, and Xc,PLA decreased, which corresponds to reduced viscosity in the PLA/PBS blend and increased mobility with higher SiC content, as indicated by the elevated MFI value. Highlights: Young's modulus increased by 40% and impact strength by 76% than pure PLA.Even SiC dispersion in PLA/PBS, possibly aided by silane coupling.SiC alters chain mobility, boosts crystalline structure, raising Tg.ΔHm and Xc,PLA reduced, suggests reduced viscosity in PLA/PBS at more SiC.Elevated MFI value shows increased chain mobility in PLA/PBS blend at more SiC. [ABSTRACT FROM AUTHOR]

Summary: This paper introduces an equivalent model including the parasitic parameters analysis of silicon carbide (SiC) MOSFETs in order to enhance their performance for high‐power density applications. The model is used to establish a mechanism that evaluates the effect of drive parameters on switching losses and electrical stress of power devices, providing a theoretical basis for optimizing the design of drive parameters. The paper finds the Pareto solution of the multi‐objective optimization model through iterative calculation of design variables, using this mechanism. The methodology is validated through experimental results from an SiC power prototype, showing an efficiency of 98.9% and safe electrical stress levels under 1500 V/100 kW operating conditions. [ABSTRACT FROM AUTHOR]

Specimens from a Hi‐Nicalon Type S/BN/SiC (MI) ceramic matrix composite with multiple machined holes were subjected to a furnace dwell and then tensile tested. The furnace temperature range was 500–900°C, and the atmosphere was pure steam to approximate the temperature and sea level partial pressure of water vapor in the cooling air going through turbomachinery cooling holes. Exposure of control specimens was done in laboratory air at the same temperatures. Tensile results along with microscopy and spectroscopy showed significant strength degradation in some conditions due primarily to oxidation of the boron nitride fiber coating, with coating volatilization at lower temperatures and probable fiber‐to‐matrix bonding and imposed fiber stresses at higher temperatures. The greatest strength degradation occurred in the 500–600°C steam range. The fiber coating oxidation/volatilization was especially evident near the holes and was exacerbated in the lower temperature tests by porosity networks that were open to the atmosphere at fiber tow ends at the specimen edges and along the inner walls of the holes. [ABSTRACT FROM AUTHOR]

Post‐oxidation annealing in oxygen (O2) ambient can improve the quality of the SiO2/SiC stack without introducing foreign atoms. In order to reveal the annealing mechanism at different oxygen partial pressures (P(O2)), this work focuses on the dependence of the annealing effect on P(O2) in a wide range from 0.01 Pa to 101 kPa for SiO2/SiC stack. In order to minimize the C‐related defects generated during SiC oxidation, the SiO2/SiC stacks are formed by oxidizing the deposited Si on the SiC epitaxial layer. The electrical characteristics of the annealed samples show that low P(O2) is beneficial to improve the interface quality, and high P(O2) is beneficial to improve the oxide layer quality. In addition, time of flight secondary ion mass spectrometry and X‐ray photoelectron spectroscopy analysis shows that the distribution and filling of oxygen vacancies (V[O]) are consistent with the electrical results. Finally, a model describing V[O] filling amount with P(O2) is proposed to quantitatively characterize the dependence of the annealing effect on P(O2), which shows that the filling amount of V[O] is proportional to P(O2)n (n∼0.065). This model provides theoretical support for improving the quality of SiC MOS by O2 annealing. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC)'s nonlinear optical properties and applications to quantum information have recently brought attention to its potential as an integrated photonics platform. However, despite its many excellent material properties, such as large thermal conductivity, wide transparency window, and strong optical nonlinearities, it is generally a difficult material for microfabrication. Here, it is shown that directly bonded silicon‐on‐silicon carbide can be a high‐performing hybrid photonics platform that does not require the need to form SiC membranes or directly pattern in SiC. The optimized bonding method yields defect‐free, uniform films with minimal oxide at the silicon–silicon–carbide interface. Ring resonators are patterned into the silicon layer with standard, complimentary metal–oxide–semiconductor (CMOS) compatible (Si) fabrication and measure room‐temperature, near‐infrared quality factors exceeding 105. The corresponding propagation loss is 5.7 dB cm−1. The process offers a wafer‐scalable pathway to the integration of SiC photonics into CMOS devices. [ABSTRACT FROM AUTHOR]

Chalcogenide perovskites are an emerging class of semiconductors particularly interesting for optoelectronic applications due to their high absorption coefficients and direct bandgaps of 1.7–1.9 eV. However, few processing routes have been developed for the synthesis of BaZrS3 thin films. The advances in the fabrication of BaZrS3 thin films using zirconium foil as precursor and substrate is a new strategy, which is compared with the results of BaZrS3 thin films deposited on silicon carbide (SiC) substrate. In this study, a stacked layer methodology, inspired by the fabrication methods used for chalcopyrites and kesterites, is employed. The main objective is to facilitate the conversion of these layers into the desired perovskite structure through annealing. In methodology, we initiated the process by depositing elemental Zr by sputtering on SiC, followed by BaS on top of the Zr through electron beam evaporation and then sulphurized and annealed at high temperature (≈1000–1050 °C) to form BaZrS3 in an inductively heated physical vapour transport setup in the presence of elemental sulphur. In the parallel approach the methodology remains same, with the sole deviation of zirconium foil, which act as both the substrate and the source. The successful synthesis of BaZrS3 is confirmed by X‐Ray diffraction (XRD), scanning electron microscopy (SEM), and energy‐dispersive X‐Ray spectroscopy (EDS), while the optical band gap is analyzed by UV‐Vis. The microstructure of the BaZrS3 films shows the polycrystalline structure and surface roughness. [ABSTRACT FROM AUTHOR]

Multiplexing technology creates several orthogonal data channels and dimensions for high‐density information encoding and is irreplaceable in large‐capacity information storage, and communication, etc. The multiplexing dimensions are constructed by light attributes and spatial dimensions. However, limited by the degree of freedom of interaction between light and material structure parameters, the multiplexing dimension exploitation method is still confused. Herein, a 7D Spin‐multiplexing technique is proposed. Spin structures with four independent attributes (color center type, spin axis, spatial distribution, and dipole direction) are constructed as coding basic units. Based on the four independent spin physical effects, the corresponding photoluminescence wavelength, magnetic field, microwave, and polarization are created into four orthogonal multiplexing dimensions. Combined with the 3D of space, a 7D multiplexing method is established, which possesses the highest dimension number compared with 6 dimensions in the previous study. The basic spin unit is prepared by a self‐developed laser‐induced manufacturing process. The free state information of spin is read out by four physical quantities. Based on the multiple dimensions, the information is highly dynamically multiplexed to enhance information storage efficiency. Moreover, the high‐dynamic in situ image encryption/marking is demonstrated. It implies a new paradigm for ultra‐high‐capacity storage and real‐time encryption. [ABSTRACT FROM AUTHOR]

We prepared two types of trench‐test metal‐oxide semiconductor field‐effect transistor (MOSFET) structures on m‐ and a‐faces in 4H silicon carbide (4H‐SiC) and investigated the anisotropic stress distribution of small trenches with a depth of 1 μm using a scanning near‐field optical Raman microscope (SNOM) that we developed. The stress distributions of σ11 (a‐axis) under the bottom of the trench for m‐face were approximately 100 MPa larger than those for a‐face, and the stress distributions of σ33 (c‐axis) under the bottom of the trench for m‐face were almost the same as those for a‐face. The experimental result agrees well with that calculated by the finite element method (FEM). These results indicate that the anisotropic stress distributions of σ11 components around the apex of the trenches of 4H‐SiC trench‐test MOSFET occur in m‐ and a‐faces. Thus, it is possible that the differences in mobilities for m‐ and a‐faces might be caused by the anisotropic stresses. [ABSTRACT FROM AUTHOR]

Background: The extremely fast delivery of doses with ultra high dose rate (UHDR) beams necessitates the investigation of novel approaches for real‐time dosimetry and beam monitoring. This aspect is fundamental in the perspective of the clinical application of FLASH radiotherapy (FLASH‐RT), as conventional dosimeters tend to saturate at such extreme dose rates. Purpose: This study aims to experimentally characterize newly developed silicon carbide (SiC) detectors of various active volumes at UHDRs and systematically assesses their response to establish their suitability for dosimetry in FLASH‐RT. Methods: SiC PiN junction detectors, recently realized and provided by STLab company, with different active areas (ranging from 4.5 to 10 mm2) and thicknesses (10–20 µm), were irradiated using 9 MeV UHDR pulsed electron beams accelerated by the ElectronFLASH linac at the Centro Pisano for FLASH Radiotherapy (CPFR). The linearity of the SiC response as a function of the delivered dose per pulse (DPP), which in turn corresponds to a specific instantaneous dose rate, was studied under various experimental conditions by measuring the produced charge within the SiC active layer with an electrometer. Due to the extremely high peak currents, an external customized electronic RC circuit was built and used in conjunction with the electrometer to avoid saturation. Results: The study revealed a linear response for the different SiC detectors employed up to 21 Gy/pulse for SiC detectors with 4.5 mm2/10 µm active area and thickness. These values correspond to a maximum instantaneous dose rate of 5.5 MGy/s and are indicative of the maximum achievable monitored DPP and instantaneous dose rate of the linac used during the measurements. Conclusions: The results clearly demonstrate that the developed devices exhibit a dose‐rate independent response even under extreme instantaneous dose rates and dose per pulse values. A systematic study of the SiC response was also performed as a function of the applied voltage bias, demonstrating the reliability of these dosimeters with UHDR also without any applied voltage. This demonstrates the great potential of SiC detectors for accurate dosimetry in the context of FLASH‐RT. [ABSTRACT FROM AUTHOR]

Xray free‐electron lasers (XFELs) enable experiments that would have been impractical or impossible at conventional X‐ray laser facilities. Indeed, more XFEL facilities are being built and planned, with their aim to deliver larger pulse energies and higher peak brilliance. While seeking to increase the pulse power, it is quintessential to consider the maximum pulse fluence that a grazing‐incidence FEL mirror can withstand. To address this issue, several studies were conducted on grazing‐incidence damage by soft X‐ray FEL pulses at the European XFEL facility. Boron carbide (B4C) coatings on polished silicon substrate were investigated using 1 keV photon energy, similar to the X‐ray mirrors currently installed at the soft X‐ray beamlines (SASE3). The purpose of this study is to compare the damage threshold of B4C and Si to determine the advantages, tolerance and limits of using B4C coatings. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharges (DBDs) are frequently utilized in various gas conversion processes. For industrial applications a low flow resistance and scalability are crucial. In this study a tenfold scaled‐up reactor based on a surface dielectric barrier discharge (SDBD) was employed for the removal of oxygen traces from H2/N2/O2 gas mixtures. The conversion efficiency of the reactor with ten electrode configurations was investigated for different admixtures of O2, and high degrees of conversion were observed that decreased with increasing flow rate, but remained constant when raising the pressure to 2 bar(g). A new generator based on silicon carbide field‐effect transistors (SiC‐FETs) was used and compared to a generator based on classical metal oxide semiconductor field‐effect transistors (MOS‐FETs). [ABSTRACT FROM AUTHOR]

The high‐temperature microstructural evolution and mechanical properties of two SiC‐based polymer‐derived ceramics with different Hf:Ta molar ratios are investigated using electron microscopy techniques and manipulated by nanoindentation. The as‐pyrolyzed ceramic powder consists of an amorphous Si(HfxTa1−x)C(N,O) structure (where x = 0.2, 0.7) with localized nanocrystalline transition metal carbides (TMCs). Subsequent application of the field‐assisted sintering technique (FAST) for high‐temperature consolidation results in a crystalline (HfxTa1−x)C/SiC ultra‐high temperature ceramic nanocomposite. The microstructure contains powder particle‐sized grains and sinter necks between the former powder particles. The powder particles consist of a β‐SiC matrix and small TMCs. Large TMCs are observed on the internal surfaces of former powder particles. This is due to the pulsed direct current and the resulting Joule heating that facilitates diffusion as well as oxygen impurities. Sinter necks of large β‐SiC grains form during the FAST process. The microstructural regions are assessed using high‐throughput nanoindentation. The hardness for SiC/(Hf0.7Ta0.3)C is measured on the formed grains and the sinter necks giving mean hardness values of about 27 and 37 GPa, respectively. [ABSTRACT FROM AUTHOR]

Polypropylene is a useful and widely consumed thermoplastic with very good properties that can be mixed with a combination of rubber and nanoparticles in order to eliminate its shortcomings. In this paper, the simultaneous combination of both the toughening effect of styrene–butadiene rubber (SBR) and the reinforcing effect of silicon carbide (SiC) nanoparticles were investigated in polypropylene matrix. Mechanical properties (tensile and impact strength [TS and IS]) of compounds were analyzed using the central composite design approach in Design‐Expert software. With two factors for input variables of SBR and SiC weight percentages, and their five levels (5, 10, 15, 20, and 25) and (0, 1.5, 3, 4.5, and 6), respectively, the central composite design approach employs 11 experiments for creation of models and the analysis of variance investigations with two output responses of TS and IS. Statistical results revealed that SBR and SiC contents had a significant effect on TS, IS, and the microstructure of compounds, as confirmed by scanning electron microscopy and energy‐dispersive spectroscopy images. To maximize all mechanical properties simultaneously with desirability functions, TS and IS of the optimum sample were computed to be 21.98 MPa and 8.66 kJ/m2 in amounts of 13.45 and 2.80 weight percentage (wt%) of SBR and SiC, respectively. Highlights: By increasing silicon carbide (SiC) in polypropylene/styrene–butadiene rubber (SBR), tensile strength decreases after a peak due to agglomeration effect.By increasing SiC in polypropylene/SBR, impact strength decreases after a peak due to agglomeration effect.By increasing SiC, the rubber particles' dimensions decrease according to scanning electron microscopy analysis.Simultaneous maximum of tensile strength and impact strength are 21.98 MPa and 8.66 KJ/m2, respectively.Optimum value of SBR and SiC in above maximums are 13.45 and 2.8 wt%, respectively. [ABSTRACT FROM AUTHOR]

Many energy systems demand heat transfer at high temperatures to keep up with high demand for power, so high‐temperature material that can perform and last under these harsh conditions is needed for heat exchangers. The engineering requirements for these high‐temperature heat exchanger material call for high thermal conductivity, high resistance to fracture, high resistance to creep deformation, environmental stability in environments associated with the application, and high modulus of elasticity while maintaining low cost to make and maintain. Naturally, ceramics are a good solution for this endeavor. In the past, high‐temperature heat exchangers made from ceramics have been used. We provide examples of ceramics in relevant heat exchange applications and provide motivation where additive manufacturing (AM) can improve efficiency. AM for the relevant material is under development, and we provide insight on the AM of ceramic materials and examples of AM heat exchangers keeping cost in mind. The motivation of the review paper is to provide a framework for material and manufacturing selection for high‐temperature heat exchangers for AM to keep up with the demand for better efficiency, better material, better manufacturing, and cost moving forward with AM technology in high‐temperature ceramic heat exchangers. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC), as a third‐generation semiconductor material, has attracted significant research attention. Various empirical potentials and machine learning potentials have been developed, but there are few comparative studies on phonon and thermal properties. Herein, the Tersoff and Vashishta empirical potentials, as well as the Bayesian force field constructed by the FLARE framework using principled Gaussian process uncertainties (FLARE BFF), for a comparative study, are selected. The phonon dispersion relation, phonon density of states, Grüneisen constants, and the average phonon‐weighted Grüneisen constants are calculated using different potentials, and it is found that the FLARE BFF potential has the highest accuracy with respect to the first‐principles calculations. Furthermore, the thermal conductivity using molecular dynamics simulation with different potentials is calculated. The calculation results using the FLARE BFF potential closely match the experimental reports at high temperature, but the longest computing time is required. This study can facilitate the understanding of thermal properties of SiC. [ABSTRACT FROM AUTHOR]

Al4SiC4 shows excellent heat resistance, thermal shock resistance, machinability, and oxidation resistance. We focused on Al4SiC4‐based ceramics with SiC as a non‐oxide matrix for ceramic matrix composites for aircraft jet engines. In this study, monolithic Al4SiC4 and Al4SiC4/SiC ceramics were fabricated by hot‐pressing, and a corrosion test against molten calcium‐magnesium‐alumino‐silicate (CMAS) was conducted at 1350°C for 12–100 h in air, and their corrosion behavior was investigated. Scanning electron microscopy and energy‐dispersive X‐ray spectroscopy results revealed that severe damage was not observed at the interface between CMAS and the samples after the CMAS corrosion test. The recession of Al4SiC4‐100, ‐10, and SiC‐100 after corrosion for 100 h was 80–90 µm, and that of Al4SiC4‐50 was the highest of all samples and the value was 130 µm. The dissolution behavior of the oxidation layer into molten CMAS via a corrosion reaction was dependent on the composition of both the sample and the oxidation layer, the thickness, and the microstructure of the oxidation layers. The dominant mechanism of reaction between CMAS and Al4SiC4‐100, ‐90, and ‐50 samples was concluded to be the dissolution of the oxidation products, while in SiC‐100 and Al4SiC4‐10 samples, the dominant reaction was determined to be direct corrosion of the surface with CMAS. [ABSTRACT FROM AUTHOR]

Silicon carbide fiber–reinforced silicon carbide (SiCf/SiC) composites have been expected to be used as next‐generation heat resistant structural materials with high reliability. The fiber/matrix interface for SiCf/SiC composites plays an important role for toughening and strengthening, and it is important to form the optimal interphase for SiCf/SiC composites. In this study, hexagonal‐boron nitride (h‐BN), which shows better oxidation resistance than carbon, was selected as the interphase for SiCf/SiC composites, and h‐BN coating was formed on low‐conductive SiC fibers by the electrophoretic deposition (EPD) method using flaked h‐BN suspension prepared by wet‐jet milling. Unidirectional SiCf/SiC composites with the BN interphase formed by the EPD method were prepared by polymer impregnation and pyrolysis (PIP) method, and their mechanical properties were evaluated. The uniform h‐BN interphase was successfully formed on the low‐conductive SiC fibers by EPD when thin polypyrrole (Ppy) coating, that is, conductive polymer, was formed on the SiC fibers. The h‐BN coating became denser by heat‐treatment at 1000°C, and the h‐BN coating deposited tightly on the SiC fibers was confirmed. It was demonstrated that the SiCf/SiC composites with the uniform and relatively dense h‐BN interphase formed by EPD using flaked h‐BN particles exhibited pseudo‐ductile fracture behavior with large amount of fiber pullout and higher fracture energy. [ABSTRACT FROM AUTHOR]

Porous SiC ceramics with three different pore sizes (∼7, ∼45, and ∼98 μm) and two different porosities (∼54% and ∼63%) were prepared to investigate the effects of pore size on electrical and thermal properties of the porous ceramics. With an increase in pore size from ∼7 to ∼98 μm at the same porosity (∼54%), the electrical and thermal conductivities of the porous ceramics increased from ∼1.01 to ∼2.30 Ω−1·cm−1 and ∼14.3 to ∼26.2 W·m−1K−1, respectively. Similar trends have been obtained in the ceramics with ∼63% porosity. The porous SiC ceramic with larger pore size has smaller pore/strut interface area at the same porosity, which leads to less carrier scattering and phonon‐pore scattering at the pore/strut interfaces, resulting in higher electrical and thermal conductivities, respectively. These results suggest that the electrical and thermal properties of porous SiC ceramics can be successfully tuned by adjusting the pore size and porosity depending on the application. [ABSTRACT FROM AUTHOR]

To assess the strength of coatings under multi‐axial stress conditions, a method was developed to evaluate the biaxial strength of thin silicon carbide (SiC) coatings using a ring‐on‐ring test. A graphite substrate was used as an intermediary to transmit stress from the load ring to the coated specimen, and the thin coating was subjected to a uniform equi‐biaxial stress. The strain in the thin film was continuously monitored using digital image correlation, allowing the identification of the time at which and when the initial crack occurred; the stress applied to the loading area at time was determined to be the fracture strength of the thin SiC films. The obtained fracture strength ranged from 209 to 1014 MPa and was dependent on specimen volume. Notably, the thinnest specimen exhibited the highest strength, whereas the strengths of thicker specimens approached previously reported bulk strengths. [ABSTRACT FROM AUTHOR]

This study focuses on the design, additive manufacturing, and characterization of silicon carbide‐based components with complex geometries. These parts were produced using a novel hybrid technique, previously developed: powder bed fusion of polyamide was used to 3D print two different templates with complex architectures. Preceramic polymer infiltrations and pyrolysis with polycarbosilane and furan resin were performed to obtain the ceramic parts. The final densification was achieved with reactive or nonreactive silicon infiltrations according to four different strategies, producing ceramics comprised of crystalline βSiC, reaction‐bonded βSiC, and low residual silicon. The final gyroid samples (∼70 vol% macroporosity) exhibited a maximum compressive strength of 24.7 ± 2.2 MPa, with a skeleton density of 3.173 ± 0.022 g/cm3, and a relative density of 0.935 ± 0.016. These findings underscore the potential of this manufacturing approach and showcase its effectiveness in fabricating intricate ceramic structures for engineering applications as heat exchangers and catalytic supports. [ABSTRACT FROM AUTHOR]

The flexural strength variability of α$\alpha$‐SiC$\text{SiC}$ based ceramics at elevated temperatures creates the need for an Integrated Computational Materials Engineering (ICME) framework that relates the strength of a specimen directly to its manufacturing process. To create this ICME framework, a model must first be developed which establishes a relationship between the chemical vapor infiltration (CVI) process and parameters, the resulting mesoscale pores, and the overall macroscale flexural strength. Here, a nonlinear single‐pore model of CVI is developed used in conjunction with a four‐way coupled thermo‐mechanical damage model. The individual components of the model are tested and a sample system under a four‐point bending test is explored. Results indicate that specimens with an initial porosity greater than 30% require temperatures below 1273 K to maintain structural integrity, while those with initial porosities less than 30% are temperature‐independent, allowing for optimization of the CVI processing time without compromising strength. [ABSTRACT FROM AUTHOR]

There is an urgent need to increase the global data storage capacity, as current approaches lag behind the exponential growth of data generation driven by the Internet, social media, and cloud technologies. In addition to increasing storage density, new solutions should provide long‐term data archiving that goes far beyond traditional magnetic memory, optical disks, and solid‐state drives. Here, a concept of energy‐efficient, ultralong, high‐density data archiving is proposed, based on optically active atomic‐size defects in a radiation resistance material, silicon carbide (SiC). The information is written in these defects by focused ion beams and read using photoluminescence or cathodoluminescence. The temperature‐dependent deactivation of these defects suggests a retention time minimum over a few generations under ambient conditions. With near‐infrared laser excitation, grayscale encoding and multi‐layer data storage, the areal density corresponds to that of Blu‐ray discs. Furthermore, it is demonstrated that the areal density limitation of conventional optical data storage media due to the light diffraction can be overcome by focused electron‐beam excitation. [ABSTRACT FROM AUTHOR]

Single‐crystal silicon carbide (SiC) is an important semiconductor material for the fabrication of power and radio frequency (RF) devices. The major technique for growing single‐crystal SiC is the so‐called physical vapor transport (PVT) method, in which not only the thermal field but also the fluid‐flow field and the distribution of gas species can be hardly measured directly. In this study, a multi‐component flow model is proposed that includes the inside and outside of a growth chamber and a joint between the seed crystal holder and crucible which allows exchanges of the gas species. The joint is simulated as a thin porous graphite sheet. The Hertz‐Knudsen equation is used to describe the sublimation and deposition. The convection and diffusion are described by the Navier–Stokes equations and mixture‐averaged diffusion model, in which the Stefan flow is taken into account. The numerical simulations are conducted by the finite element method (FEM) with a multi‐physics coupled model, which is able to predict the fluid flow field, species distribution field, crystal growth rate, and evolution of the molar concentration of dopant gas. Using this model, the effects of several experimental conditions on the transport of gas species and the growth rate of single‐crystal SiC are analyzed. [ABSTRACT FROM AUTHOR]

Cubic silicon carbide (3C‐SiC) has superior mobility and thermal conduction over that of widely applied hexagonal 4H‐SiC. Moreover, much lower concentration of interfacial traps between insulating oxide gate and 3C‐SiC helps fabricate reliable and long‐life devices like metal‐oxide‐semiconductor field effect transistors. However, the growth of high‐quality and wafer‐scale 3C‐SiC crystals has remained a big challenge up to now despite decades‐long efforts by researchers because of its easy transformation into other polytypes during growth, limiting the development of 3C‐SiC‐based devices. Herein, we report that 3C‐SiC can be made thermodynamically favored from nucleation to growth on a 4H‐SiC substrate by top‐seeded solution growth technique, beyond what is expected by classical nucleation theory. This enables the steady growth of high‐quality and large‐size 3C‐SiC crystals (2–4‐inch in diameter and 4.0–10.0 mm in thickness) sustainable. The as‐grown 3C‐SiC crystals are free of other polytypes and have high‐crystalline quality. Our findings broaden the mechanism of hetero‐seed crystal growth and provide a feasible route to mass production of 3C‐SiC crystals, offering new opportunities to develop power electronic devices potentially with better performances than those based on 4H‐SiC. [ABSTRACT FROM AUTHOR]

The design of multifunctional materials with good thermophysical and electromagnetic shielding properties is desirable to overcome overheating and electromagnetic interference (EMI) in electronic devices. In this study, three‐dimensional (3D) continuous SiC skeleton‐reinforced highly oriented graphite flake (GF@SiC) composites were fabricated by combining molten salt synthesis, heat treatment, and spark plasma sintering. When the SiC content was higher than 9 vol.%, a 3D continuous SiC skeleton was formed, which effectively constrained the cross‐plane thermal expansion of the GF@SiC composites. Highly oriented GFs endowed the composites with good thermal conductivity (TC) along the basal plane and effective EMI shielding in the X‐band. The composites with SiC concentrations of 9 vol.% exhibited an optimal comprehensive performance with a high TC of 322 W/m/K in the basal plane direction, a low thermal expansion value of 10.5 × 10−6/K in the through‐plane direction, and EMI shielding effectiveness of 36 dB. Our strategy provides a promising and practical approach for realizing graphite‐based composites to meet the current demands for electronic devices. [ABSTRACT FROM AUTHOR]

Fabricating and introducing new materials with new features is one of the most important goals for many scientific groups. Today, additive manufacturing (AM) is known as one of the new production methods, which can create an excellent opportunity for achieving this goal. As one of the ongoing production processes, the laser AM (LAM) methods have the proper capacity for producing new advanced materials like carbide, nitride, and boride‐based materials. Hence, this work aims to review carbide‐based materials produced by LAM techniques with the composite viewpoint. These materials can act as a matrix, reinforcement, or tertiary component in advanced composites. With this viewpoint, these composite materials were introduced in eight separate sections, which are tungsten carbide, titanium carbide, silicon carbide, niobium carbide, chrome carbide, vanadium carbide, and boron carbide, as well as high entropy alloy composites. [ABSTRACT FROM AUTHOR]

Polysilazane (PSZ) polymers offer the ability to form silicon carbide (SiC) or silicon nitride (Si3N4) via thermal pyrolysis. The majority of studies surrounding this polymer have focused on the decomposition of PSZ to amorphous glass. Investigations into the structural defects and bonding environments of the final ceramic systems are not as frequently discussed. Examining structural defects/abnormalities can help better use PSZ‐derived ceramics in electronic and high‐temperature applications, where phase identity and microstructure are important. In this work, three PSZ‐derived polymers were synthesized with different C/N ratios (1.33, 1.0, and 1.2) via the ammonolysis condensation reaction with chlorinated silanes. The samples were named PSZ‐SiCF1‐3. Samples were then pyrolyzed under Ar in a tube furnace at 1600°C for 5 h. Characterization included X‐ray diffraction (XRD), Raman spectroscopy, X‐ray photoelectron spectroscopy, scanning transmission electron microscopy, and electron energy loss spectroscopy. XRD measurements uncovered arbitrary stacking fault (SF) measurements of 3C‐SiC to be 4.12, 1.08, and 2.12 (unitless) for samples PSZ‐SiCF1‐3. Results were supported through Raman spectroscopy and TEM. High carbon content, not higher residual nitrogen content, was more impactful for SF formation. This highlights the importance of SFs in the microstructural evolution of non‐oxide ceramics. [ABSTRACT FROM AUTHOR]

This study aimed to develop a power supply system without a traction transformer for weight reduction and downsizing. Transformer‐less power supply is expected to realize step‐down, rectification, isolation, and motor drive using a high‐voltage silicon carbide power device. The primary challenge of this study was developing a novel circuit that isolates the motor drive circuit from the AC line without using the traction transformer. Accordingly, we devised a flying capacitor circuit to solve the existing problems and achieve capacitive isolation. Subsequently, we devised a nesting capacitor as a short‐circuit prevention measure. In this study, the operation of the isolated circuit was verified by numerical simulation, complemented by experimental verification of the proposed circuit. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) is used in a variety of applications including photovoltaic due to its high stability. The wide bandgap of SiC limits these applications and necessitates bandgap tuning toward lower energy for efficient solar absorption. In this regard, the electronic properties of highly stable SiC polytype 6H‐SiC are studied by first‐principles calculations. By varying the Si composition of 6H‐SiC the electronic properties are tailored. The calculated results show that increasing the Si composition of 6H‐SiC from 50% to 66.66% reduces the bandgap from 2.98 to 1.54 eV. It is observed that this reduction in bandgap occurs due to the addition of extra Si s/p orbitals which close the conduction band and valance band. From the electronic conductivity calculations, it is found that with increasing Si composition of 6H‐SiC the conductivity is improved due to higher hole density which can be verified by the spectrum peaks shifted toward near‐infrared and visible region. [ABSTRACT FROM AUTHOR]

High thermally conductive polymer composites have garnered significant attention due to their exceptional performance, given the ever‐decreasing size of electronic devices and the rise in power densities. Herein, a new three‐dimensional (3D) thermal conductivity network structure has been successfully prepared using double fillers of nickel foam (NF) and modified silicon carbide particles (KSiC). The study compared the effect of different filler contents on the thermal conductivity of composites. Compared to conventional composites, those based on 3D filling networks have significantly improved thermal conductivity. The thermal conductivity of the NF/KSiC/PU composite containing 50 wt% KSiC was 1.18 Wm−1 K−1, exceeding the cumulative thermal conductivity of the NF/PU and KSiC/PU 50 wt% composites, and 637.5% greater than that of neat PU. Meanwhile, the synthesized NF/KSiC/PU composite maintained a high electrical resistivity above 1012 Ω·cm and good mechanical properties. This approach might offer novel solutions for developing high‐quality packaging materials for advanced electronic devices with exceptional thermal and mechanical properties. Highlights: Using SiC and NF Constructs a dual filler network.The dual filler thermal conductivity network can generate synergistic effects.Improving thermal conductivity compared to original polyurethane.Maintaining a high electrical resistivity and good mechanical properties. [ABSTRACT FROM AUTHOR]