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Preparation and Analysis of Carbon Fiber-Silicon Carbide Thermally Conductive Asphalt Concrete
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作者 Zhiyong Yang Enjie Hu +3 位作者 Lei Xi Zhi Chen Feng Xiong Chuanhai Zhan 《Fluid Dynamics & Materials Processing》 EI 2024年第4期705-723,共19页
An experimental investigation into the thermal conductivity of CF-SiC two-phase composite asphalt concrete is presented.The main objective of this study was to verify the possibility of using SiC powder instead of min... An experimental investigation into the thermal conductivity of CF-SiC two-phase composite asphalt concrete is presented.The main objective of this study was to verify the possibility of using SiC powder instead of mineral powder as the thermal conductive filler to prepare a new type of asphalt concrete and improve the efficiency of electrothermal snow and ice melting systems accordingly.The thermal conductivity of asphalt concrete prepared with different thermally conductive fillers was tested by a transient plane source method,and the related performances were measured.Then the temperature rise rate and surface temperature were studied through field heating tests.Finally,the actual ice melting efficiency of the thermally conductive asphalt concrete was evaluated using an effective electrothermal system.As shown by the experimental results,the composite made of SiC powder and carbon fiber has a high thermal conductivity.When SiC replaces mineral powder,the thermal conductivity of the asphalt mixture increases first and then decreases with the increase of carbon fiber content.In the present study,in particular,the thermal conductivity attained a peak when the carbon fiber content was 0.2%of the aggregate mass. 展开更多
关键词 Carbon fiber silicon carbide thermally conductive asphalt concrete road performance electrothermal snow melting
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Influence of Carbon Content on Element Diffusion in Silicon Carbide-Based TRISO Composite Fuel
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作者 Xiaojiao Wang Libing Zhu +1 位作者 Yan You Zhaoquan Zhang 《Journal of Electronic Research and Application》 2024年第5期80-88,共9页
The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,... The coating layers of Tri-structural Isotropic Particles(TRISO)serve to protect the kernel and act as barriers to fission products.Sintering aids in the silicon carbide matrix variably react with TRISO coating layers,leading to the destruction of the coating layers.Investigating how carbon content affects element diffusion in silicon carbide-based TRISO composite fuel is of great significance for predicting reactor safety.In this study,silicon carbide-based TRISO composite fuels with different carbon contents were prepared by adding varying amounts of phenolic resin to the silicon carbide matrix.X-ray Diffraction(XRD)and Scanning Electron Microscopy(SEM)were employed to characterize the phase composition,morphology,and microstructure of the composite fuels.The elemental content in each coating layer of TRISO was quantified using Energy-Dispersive X-ray Spectroscopy(EDS).The results demonstrated that the addition of phenolic resin promoted the uniform distribution of sintering aids in the silicon carbide matrix.The atomic percentage(at.%)of aluminum(Al)in the pyrolytic carbon layer of the TRISO particles reached its lowest value of 0.55%when the phenolic resin addition was 1%.This is because the addition of phenolic resin caused the Al and silicon(Si)in the matrix to preferentially react with the carbon in the phenolic resin to form a metastable liquid phase,rather than preferentially consuming the pyrolytic carbon in the outer coating layer of the TRISO particles.The findings suggest that carbon addition through phenolic resin incorporation can effectively mitigate the deleterious reactions between the TRISO coating layers and sintering aids,thereby enhancing the durability and safety of silicon carbide-based TRISO composite fuels. 展开更多
关键词 silicon carbide TRISO Composite fuel Diffusion behavior Carbon content
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Research on Silicon Carbide Dispersion-Reinforced Hypereutectic Aluminum-Silicon Electronic Packaging Materials
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作者 Ruixi Guo Yunhao Hua Tianze Jia 《Journal of Electronic Research and Application》 2024年第2期86-94,共9页
The objective of this study is to improve the mechanical properties and machining performance of high thermal conductivity and low expansion silicon carbide dispersion-strengthened hypereutectic aluminum-silicon elect... The objective of this study is to improve the mechanical properties and machining performance of high thermal conductivity and low expansion silicon carbide dispersion-strengthened hypereutectic aluminum-silicon electronic packaging materials to meet the needs of aviation,aerospace,and electronic packaging fields.We used the powder metallurgy method and high-temperature hot pressing technology to prepare SiC/Al-Si composite materials with different SiC contents(5vol%,10vol%,15vol%,and 20vol%).The results showed that as the SiC content increased,the tensile strength of the composite material first increased and then decreased.The tensile strength was the highest when the SiC content was 15%;the sintering temperature significantly affected the composite material’s structural density and mechanical properties.Findings indicated 700℃was the optimal sintering and the optimal SiC content of SiC/Al-Si composite materials was between 10%and 15%.Besides,the sintering temperature should be strictly controlled to improve the material’s structural density and mechanical properties. 展开更多
关键词 silicon carbide Electronic packaging materials Powder metallurgy Mechanical properties Composite materials
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Advanced research on the preparation and application of carbide ceramic fibers
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作者 Zhongqian Zhao Wei Liao +3 位作者 Jing Chen Jian Jiao Cuilan Wu Yanzi Gou 《Journal of Advanced Ceramics》 SCIE EI CAS CSCD 2024年第9期1291-1336,共46页
Carbide ceramic fibers are of significant importance for application in the high-tech areas of advanced aircraft engines,aerospace vehicles,and the nuclear industry due to their excellent properties,such as high tensi... Carbide ceramic fibers are of significant importance for application in the high-tech areas of advanced aircraft engines,aerospace vehicles,and the nuclear industry due to their excellent properties,such as high tensile strength and elastic modulus,excellent high-temperature resistance,and oxidation resistance.This paper reviews the preparation and application of different carbide ceramic fibers,including SiC fibers and transition metal carbide(e.g.,ZrC,HfC,and TaC)ceramic fibers.The preparation methods of carbide ceramic fibers are discussed in terms of different fiber diameters,represented by SiC fibers with variable weaving properties and functions due to their differences in diameter.Subsequently,the application of carbide ceramic fibers as high-temperature-resistant structural materials,catalyst carriers,sensors,and supercapacitors are summarized,and strategies for the future development of carbide ceramic fibers are proposed.This review aims to help researchers enhance their understanding of the preparation and utilization of carbide ceramic micro/nanofibers,advancing the development of high-performance carbide ceramic fibers. 展开更多
关键词 carbide ceramic fibers sic fibers boron carbide(B_(4)C)fibers ultra-high temperature ceramics sic ceramic fiber-reinforced sic(sicf/sic)composites
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Application of silicon carbide temperature monitors in 49-2 swimming-pool test reactor 被引量:1
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作者 宁广胜 张利民 +6 位作者 钟巍华 王绳鸿 刘心语 汪定平 何安平 刘健 张长义 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期97-101,共5页
High purity SiC crystal was used as a passive monitor to measure neutron irradiation temperature in the 49-2 research reactor.The SiC monitors were irradiated with fast neutrons at elevated temperatures to 3.2×10... High purity SiC crystal was used as a passive monitor to measure neutron irradiation temperature in the 49-2 research reactor.The SiC monitors were irradiated with fast neutrons at elevated temperatures to 3.2×10^(20)n/cm^(2).The isochronal and isothermal annealing behaviors of the irradiated SiC were investigated by x-ray diffraction and four-point probe techniques.Invisible point defects and defect clusters are found to be the dominating defect types in the neutron-irradiated SiC.The amount of defect recovery in SiC reaches a maximum value after isothermal annealing for 30 min.Based on the annealing temperature dependences of both lattice swelling and material resistivity,the irradiation temperature of the SiC monitors is determined to be~410℃,which is much higher than the thermocouple temperature of 275℃ recorded during neutron irradiation.The possible reasons for the difference are carefully discussed. 展开更多
关键词 silicon carbide irradiation temperature monitor research reactor
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High-pressure and high-temperature sintering of pure cubic silicon carbide:A study on stress-strain and densification
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作者 刘金鑫 彭放 +5 位作者 马国龙 梁文嘉 何瑞琦 管诗雪 唐越 向晓君 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期498-505,共8页
Silicon carbide(SiC)is a high-performance structural ceramic material with excellent comprehensive properties,and is unmatched by metals and other structural materials.In this paper,raw SiC powder with an average grai... Silicon carbide(SiC)is a high-performance structural ceramic material with excellent comprehensive properties,and is unmatched by metals and other structural materials.In this paper,raw SiC powder with an average grain size of 5μm was sintered by an isothermal-compression process at 5.0 GPa and 1500?C;the maximum hardness of the sintered samples was31.3 GPa.Subsequently,scanning electron microscopy was used to observe the microscopic morphology of the recovered SiC samples treated in a temperature and extended pressure range of 0-1500?C and 0-16.0 GPa,respectively.Defects and plastic deformation in the SiC grains were further analyzed by transmission electron microscopy.Further,high-pressure in situ synchrotron radiation x-ray diffraction was used to study the intergranular stress distribution and yield strength under non-hydrostatic compression.This study provides a new viewpoint for the sintering of pure phase micron-sized SiC particles. 展开更多
关键词 high pressure and high temperature silicon carbide stress analysis DEFECT
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Unveiling phonon frequency-dependent mechanism of heat transport across stacking fault in silicon carbide
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作者 王甫 孙彦东 +2 位作者 邹宇 徐贲 付宝勤 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期373-380,共8页
Stacking faults(SFs)are often present in silicon carbide(SiC)and affect its thermal and heat-transport properties.However,it is unclear how SFs influence thermal transport.Using non-equilibrium molecular dynamics and ... Stacking faults(SFs)are often present in silicon carbide(SiC)and affect its thermal and heat-transport properties.However,it is unclear how SFs influence thermal transport.Using non-equilibrium molecular dynamics and lattice dynamics simulations,we studied phonon transport in SiC materials with an SF.Compared to perfect SiC materials,the SF can reduce thermal conductivity.This is caused by the additional interface thermal resistance(ITR)of SF,which is difficult to capture by the previous phenomenological models.By analyzing the spectral heat flux,we find that SF reduces the contribution of low-frequency(7.5 THz-12 THz)phonons to the heat flux,which can be attributed to SF reducing the phonon lifetime and group velocity,especially in the low-frequency range.The SF hinders phonon transport and results in an effective interface thermal resistance around the SF.Our results provide insight into the microscopic mechanism of the effect of defects on heat transport and have guiding significance for the regulation of the thermal conductivity of materials. 展开更多
关键词 silicon carbide stacking fault thermal conductivity interface thermal resistance phonon transport spectral heat flux
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Steam Oxidation Resistance Comparison of Several Silicon Carbide Refractories at Elevated Temperatures
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作者 WANG Jiaping WU Jiguang +2 位作者 HUANG Zhigang LYU Chunjiang WANG Wenwu 《China's Refractories》 CAS 2023年第2期18-23,共6页
The oxidation tests of different SiC refractories including Si3N4-SiC bricks,Si3N4-Si2N2O-SiC bricks from China(SNO-1),Si3N4-Si2N2O-SiC bricks from overseas(SNO-2),SiAlON-SiC bricks,oxides bonded SiC bricks,self-bonde... The oxidation tests of different SiC refractories including Si3N4-SiC bricks,Si3N4-Si2N2O-SiC bricks from China(SNO-1),Si3N4-Si2N2O-SiC bricks from overseas(SNO-2),SiAlON-SiC bricks,oxides bonded SiC bricks,self-bonded SiC bricks as well as SiC castables were carried out in the steam atmosphere(1 000 ℃,32 kg·m-3·h-1)for different durations(100,200,300,400 and 500 h).The mass,the volume,the bulk density and the apparent porosity before and after the oxidation were tested.The XRD and SEM analyses were conducted.The results indicate that:(1)under the steam atmosphere condition(1 000 ℃,32 kg·m-3·h-1),as the oxidation time increases from 0 to 500 h,the volume and the mass of the silicon carbide refractories increase,while the bulk density decreases;in terms of the apparent porosity,oxides bonded SiC bricks and SiC castables present an increasing trend,Si3N4-SiC bricks,SiAlON-SiC bricks and self-bonded SiC bricks present an increasing trend first and then a decreasing trend,and Si3N4-Si2N2O-SiC bricks present a decreasing trend or a trend of decreasing first and then increasing;(2)as for Si3N4-Si2N2O-SiC bricks,SNO-1 and SNO-2 have basically the same chemical and phase composition,SNO-2 has the lower mass change rate than SNO-1 during oxidation from 200-500 h,which indicates that SNO-2 has the better steam oxidation resistance than SNO-1. 展开更多
关键词 silicon carbide REFRACTORIES STEAM oxidation resistance
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Development and Application of Multi-phase Nitrides Bonded Silicon Carbide Lintel Blocks for Dry Quenching Furnaces
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作者 CAO Huiyan FENG Yanbin +4 位作者 ZHANG Xinhua HUANG Zhigang LI Jie WANG Xinhui WU Jiguang 《China's Refractories》 CAS 2023年第2期7-11,共5页
Multi-phase nitrides bonded silicon carbide lintel blocks were prepared using industrial SiC(SiC≥98 mass%,3-0.5,≤0.5 and≤0.044 mm),Si powder(Si≥98 mass%,≤0.044 mm),and SiO2 micropowder(SiO2≥96 mass%,d50=0.15 pm)... Multi-phase nitrides bonded silicon carbide lintel blocks were prepared using industrial SiC(SiC≥98 mass%,3-0.5,≤0.5 and≤0.044 mm),Si powder(Si≥98 mass%,≤0.044 mm),and SiO2 micropowder(SiO2≥96 mass%,d50=0.15 pm)as raw materials,and calcium lignosulfonate as the additive,batching,mixing,and molding on a vibration pressure molding machine,drying and then firing at 1420℃for 10 h in high-purity N2.The apparent porosity,the bulk density,the cold modulus of rupture,the hot modulus of rupture,and the linear expansion coefficient of the samples were tested.The phase composition and the microstructure of the samples at different nitriding depths(50,100,and 150 mm)were analyzed by XRD and SEM.The field application effects of the blocks were studied.The results show that:(1)the multi-phase nitrides bonded silicon carbide refractories can dynamically adjust their own phase composition and minimize structural and thermal stresses,improving the service life of key parts of dry quenching furnaces;(2)calcium lignosulfonate can improve the nitriding micro-environment of multi-phase nitrides bonded silicon carbide lintel blocks,successfully increasing the effective nitriding thickness of the blocks to 300 mm;(3)Sinosteel LI RR provides a unique concept in the design of materials and block types as well as the stable and scientific overall structure,promoting the industrialization process of dry quenching furnaces with long service life in China. 展开更多
关键词 inclined channel area dry quenching furnaces silicon carbide multi-phase nitrides lintel blocks
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Temperature Fluctuation Synthesis/Simultaneous Densification and Microstructure Control of Titanium Silicon Carbide (Ti_3SiC_2) Ceramics 被引量:2
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作者 Zhimei SUN and Yanchun ZHOU (Ceramic and Composite Department, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第5期461-465,共5页
A novel temperature fluctuation synthesis/simultaneous densification process was developed for the preparation of Ti3SiC2 bulk ceramics. In this process. Si is used as an in-situ liquid forming phase and it is favorab... A novel temperature fluctuation synthesis/simultaneous densification process was developed for the preparation of Ti3SiC2 bulk ceramics. In this process. Si is used as an in-situ liquid forming phase and it is favorable for both the solid-liquid synthesis and the densification of Ti3SiC2 rainies. The present work demonstrated that the temperature fluctuation synthesis/simultaneous densification process is one of the most effective and simple methods for the preparation of Ti3SiC2 bulk materials providing relatively low synthesis temperature. short reaction time; and simultaneous synthesis and densification. This work also showed the capability to control the microstructure, e.g., the preferred orientation, of the bulk Ti3SiC2 materials simply by applying the hot pressing pressure at different Stages of the temperature fluctuation process. And textured Ti3SiC2 bulk materials with {002} faces of laminated Ti3SiC2 grains normal to the hot pressing axis were prepared. 展开更多
关键词 CERAMICS Temperature Fluctuation Synthesis/Simultaneous Densification and Microstructure Control of Titanium silicon carbide TI3sic2 sic
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Effect of Addition of Polytetrafluoroethylene (PTFE) and Silicon Carbide (SiC) on Properties of Electroless Nickel Alloy Coatings 被引量:1
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作者 WUYu-cheng HUXiao-ye WANGWen.fang HUANGXin-min 《材料热处理学报》 EI CAS CSCD 北大核心 2004年第05B期1102-1105,共4页
Electroless nickel (copper)-phosphorus-silicon carbide (SiC)-polytetrafluoroethylene (PTFE) composite coatings were prepared by adding SiC and PTFE into electroless nickel (copper)-phosphorus alloy baths. The effects ... Electroless nickel (copper)-phosphorus-silicon carbide (SiC)-polytetrafluoroethylene (PTFE) composite coatings were prepared by adding SiC and PTFE into electroless nickel (copper)-phosphorus alloy baths. The effects of addition of SiC and PTFE on depositing rate, microhardness, wear resistance and anti-friction of the resulted composite coatings were studied. The results indicated that electroless nickel (copper)-phosphorus alloy coatings were greatly improved in depositing rate, microhardness, wear resistance and antifriction by co-deposited proper amount of SiC and PTFE. 展开更多
关键词 非电解淀积 聚四氟乙烯 碳化硅 镍合金
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Electroless copper-phosphorus coatings with the addition of silicon carbide (SiC) particles
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作者 Soheila Faraji Afidah Abdul Rahim +1 位作者 Norita Mohamed Coswald Stephen Sipaut 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2011年第5期615-622,共8页
Cu-P-silicon carbide (SiC) composite coatings were deposited by means of electroless plating.The effects of pH values,temperature,and different concentrations of sodium hypophosphite (NaH2PO2·H2O),nickel sulf... Cu-P-silicon carbide (SiC) composite coatings were deposited by means of electroless plating.The effects of pH values,temperature,and different concentrations of sodium hypophosphite (NaH2PO2·H2O),nickel sulfate (NiSO4·6H2O),sodium citrate (C6H5Na3O7·2H2O) and SiC on the deposition rate and coating compositions were evaluated,and the bath formulation for Cu-P-SiC composite coatings was optimised.The coating compositions were determined using energy-dispersive X-ray analysis (EDX).The corresponding optimal operating parameters for depositing Cu-P-SiC are as follows:pH 9;temperature,90oC;NaH2PO2·H2O concentration,125 g/L;NiSO4·6H2O concentration,3.125 g/L;SiC concentration,5 g/L;and C6H5Na3O7·2H2O concentration,50 g/L.The surface morphology of the coatings analysed by scanning electron microscopy (SEM) shows that Cu particles are uniformly distributed.The hardness and wear resistance of Cu-P composite coatings are improved with the addition of SiC particles and increase with the increase of SiC content. 展开更多
关键词 electroless deposited coating electroless copper plating silicon carbide particles sodium hypophosphite HARDNESS wear resis-tance
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2H-SiC Dendritic Nanocrystals In Situ Formation from Amorphous Silicon Carbide under Electron Beam Irradiation
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作者 Li Xianxiang Hu Xiaobo +3 位作者 Jiang Shouzheng Dong Jie Xu Xiangang Jiang Minhua 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z1期54-55,共2页
Under electron beam irradiation,the in-situ formation of 2H-SiC dentritic nanocrystals from amorphous silicon carbide at room temperature was observed.The homogenous transition mainly occurs at the thin edge and on th... Under electron beam irradiation,the in-situ formation of 2H-SiC dentritic nanocrystals from amorphous silicon carbide at room temperature was observed.The homogenous transition mainly occurs at the thin edge and on the surface of specimen where the energy obtained from electron beam irradiation is high enough to cause the amorphous crystallizing into 2H-SiC. 展开更多
关键词 electron beam irradiation 2H-sic dendritic nanocrystal amorphous silicon carbide
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Static and Dynamic Characterization of High-Speed Silicon Carbide (SiC) Power Transistors
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作者 Johnson A. Asumadu James D. Scofield 《Engineering(科研)》 2010年第9期673-682,共10页
This paper describes the operating characteristics of NPN 4H-SiC (a polytype of silicon carbide) bipolar junction transistor (BJT) and 4H-SiC Darlington Pairs. A large amount of experimental data was collected. The wa... This paper describes the operating characteristics of NPN 4H-SiC (a polytype of silicon carbide) bipolar junction transistor (BJT) and 4H-SiC Darlington Pairs. A large amount of experimental data was collected. The wafer BJTs were able to block over the rated 600 V in the common-emitter configuration and the TO-220 BJTs were able to block over the 1200 V rated voltage. In the thermal analysis, it is found out that at higher temperatures the forward and reverse (blocking) characteristics were stable at 100°C and 200°C. The transistors show positive temperature coefficients of forward voltage (Vf). In general the current gain (β) characteristics obtained (with VCE = 6 V) were approximately as expected for the BJTs. The β‘s were very low (2 to 5 for wafer BJTs, 5 to 20 for the wafer Darlington Pairs, and 5 to 30 for TO-220 BJTs). The large amount of experimental data collected confirms some of the superior properties of the Silicon carbide material when used to fabricate power semiconductor devices, namely high thermal conductivity and high temperature operability. The data presented here will establish the trends and the performance of silicon carbide devices. The silicon carbide BJT has fast switching and recovery characteristics. From the analysis, silicon carbide power devices will be smaller (about 20 times) than a similar silicon power device and with reduced power losses. Silicon carbide will also be very useful for device integration in high densities, as found in integrated chips for current handling capabilities, for applications in instrumentation and measurements. Presently, most of the research is on improving the basic silicon carbide material quality, power device optimization, and applications engineering using devices that have been developed to date. 展开更多
关键词 silicon carbide STATIC CHARACTERISTICS Dynamic CHARACTERISTICS
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Influence of pyrolysis temperature on structure and dielectric properties of polycarbosilane derived silicon carbide ceramic 被引量:2
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作者 丁冬海 周万城 +2 位作者 周璇 罗发 朱冬梅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2726-2729,共4页
β-SiC ceramic powders were obtained by pyrolyzing polycarbosilane in vacuum at 800-1200 °C. The β-SiC ceramic powders were characterized by TGA/DSC, XRD and Raman spectroscopy. The dielectric properties of β-S... β-SiC ceramic powders were obtained by pyrolyzing polycarbosilane in vacuum at 800-1200 °C. The β-SiC ceramic powders were characterized by TGA/DSC, XRD and Raman spectroscopy. The dielectric properties of β-SiC ceramic powders were investigated by measuring their complex permittivity by rectangle wave guide method in the frequency range of 8.2-18 GHz. The results show that both real part ε′ and imaginary part ε″ of complex permittivity increase with increasing pyrolysis temperature. The mechanism was proposed that order carbon formed at high temperature resulted in electron relaxation polarization and conductance loss, which contributes to the increase in complex permittivity. 展开更多
关键词 silicon carbide ceramic polycarbosilane derived sic dielectric properties pyrolysis temperature free carbon complexpermittivity
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Preparation and properties of porous silicon carbide ceramics through coat-mix and composite additives process 被引量:2
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作者 赵宏生 刘中国 +3 位作者 杨阳 刘小雪 张凯红 李自强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1329-1334,共6页
The core-shell structure silicon-resin precursor powders were synthesized through coat-mix process and addition of Al2O3-SiO2-Y2O3 composite additives.A series of porous silicon carbide ceramics were produced after mo... The core-shell structure silicon-resin precursor powders were synthesized through coat-mix process and addition of Al2O3-SiO2-Y2O3 composite additives.A series of porous silicon carbide ceramics were produced after molding,carbonization and sintering.The phase,morphology,porosity,thermal conductivity,thermal expansion coefficient,and thermal shock resistance were analyzed.The results show that porous silicon carbide ceramics can be produced at low temperature.The grain size of porous silicon carbide ceramic is small,and the thermal conductivity is enhanced significantly.Composite additives also improve the thermal shock resistance of porous ceramics.The bending strength loss rate after 30 times of thermal shock test of the porous ceramics which were added Al2O3-SiO2-Y2O3 and sintered at 1 650 ℃ is only 6.5%.Moreover,the pore inside of the sample is smooth,and the pore size distribution is uniform.Composite additives make little effect on the thermal expansion coefficient of the porous silicon carbide ceramics. 展开更多
关键词 silicon carbide porous ceramic coat-mix composite additives
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Effect of High Temperature Annealing on Characteristics of 4H Silicon Carbide MESFET 被引量:1
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作者 杨林安 张义门 +3 位作者 于春利 张玉明 陈刚 黄念宁 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期486-491,共6页
For very high temperature annealing (1620℃) after ion implantation for 4H silicon carbide (4H SiC),the residual components of Al and O in the alundum furnace impact seriously on the surface of material,which yields ... For very high temperature annealing (1620℃) after ion implantation for 4H silicon carbide (4H SiC),the residual components of Al and O in the alundum furnace impact seriously on the surface of material,which yields the derivation of SiOC.This causes a significant degradation of the 4H SiC surface characteristics according to the results of surface composition analysis.As validity,Ni/SiC ohmic contact measurement illustrates a higher specific contact resistance than the normal value by a factor of 2~3.Consequently the MESFET fabricated with this kind of 4H SiC material results in a degraded I V output performance compared with that of normal 4H SiC MESFET. 展开更多
关键词 silicon carbide ANNEALING surface composition analysis ohmic contact I-V characteristics
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Evidence of the Role of Carbon Vacancies in Nickel-Based Ohmic Contacts to n-Type Silicon Carbide 被引量:1
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作者 郭辉 张义门 张玉明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第1期5-9,共5页
N-wells are created by P+ ion implantation into Si-faced p-type 4H-SiC epilayer. Ti and Ni are deposited in sequence on the surface of the active regions. Ni2Si is identified as the dominant phase by X-ray diffracti... N-wells are created by P+ ion implantation into Si-faced p-type 4H-SiC epilayer. Ti and Ni are deposited in sequence on the surface of the active regions. Ni2Si is identified as the dominant phase by X-ray diffraction (XRD) analysis after metallization annealing. An amorphous C film at the Ni2 Si/SiC interface is confirmed by an X-ray energy-dispersive spectrometer (XEDS). The Ni2Si and amorphous C film are etched away selectively,followed by deposition of new metal films without annealing. Measurement of the current-voltage characteristics shows that the contacts are still ohmic after the Ni2 Si and amorphous C film are replaced by new metal films. The sheet resistance Rsh of the implanted layers decreases from 975 to 438f2/D, because carbon vacancies (Vc) appeared during annealing,which act as donors for electrons in SiC. 展开更多
关键词 NI ohmic contact silicon carbide carbon vacancies P^+ ion implantation
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适用于SiC MOSFET的漏源电压积分自适应快速短路保护电路研究 被引量:1
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作者 李虹 胡肖飞 +1 位作者 王玉婷 曾洋斌 《中国电机工程学报》 EI CSCD 北大核心 2024年第4期1542-1552,I0024,共12页
SiC MOSFET因其高击穿电压、高开关速度、低导通损耗等性能优势而被广泛应用于各类电力电子变换器中。然而,由于其短路耐受时间仅为2~7μs,且随母线电压升高而缩短,快速可靠的短路保护电路已成为其推广应用的关键技术之一。为应对不同... SiC MOSFET因其高击穿电压、高开关速度、低导通损耗等性能优势而被广泛应用于各类电力电子变换器中。然而,由于其短路耐受时间仅为2~7μs,且随母线电压升高而缩短,快速可靠的短路保护电路已成为其推广应用的关键技术之一。为应对不同母线电压下的Si C MOSFET短路故障,文中提出一种基于漏源电压积分的自适应快速短路保护方法(drain-sourcevoltageintegration-basedadaptivefast short-circuit protection method,DSVI-AFSCPM),研究所提出的DSVI-AFSCPM在硬开关短路(hardswitchingfault,HSF)和负载短路(fault under load,FUL)条件下的保护性能,进而研究不同母线电压对DSVI-AFSCPM的作用机理。同时,探究Si CMOSFET工作温度对其响应速度的影响。最后,搭建实验平台,对所提出的DSVI-AFSCPM在发生硬开关短路和负载短路时不同母线电压、不同工作温度下的保护性能进行实验测试。实验结果表明,所提出的DSVI-AFSCPM在不同母线电压下具有良好的保护速度自适应性,即母线电压越高,短路保护速度越快,并且其响应速度受Si CMOSFET工作温度影响较小,两种短路工况下工作温度从25℃变化到125℃,短路保护时间变化不超过90 ns。因此,该文为Si CMOSFET在不同母线电压下的可靠使用提供一定技术支撑。 展开更多
关键词 碳化硅金属氧化物半导体场效应晶体管 短路保护 漏源电压积分 母线电压 自适应
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Fabrication of n^+ Polysilicon Ohmic Contacts with a Heterojunction Structure to n-Type 4H-Silicon Carbide
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作者 郭辉 冯倩 +2 位作者 汤晓燕 张义门 张玉明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期637-640,共4页
Polysilicon ohmic contacts to n-type 4H-SiC have been fabricated. TLM (transfer length method) test patterns with polysilicon structure are formed on n-wells created by phosphorus ion (P^+) implantation into a Si... Polysilicon ohmic contacts to n-type 4H-SiC have been fabricated. TLM (transfer length method) test patterns with polysilicon structure are formed on n-wells created by phosphorus ion (P^+) implantation into a Si-faced p-type 4H-SiC epilayer. The polysilicon is deposited using low-pressure chemical vapor deposition (LPCVD) and doped by phosphorous ions implantation followed by diffusion to obtain a sheet resistance of 22Ω/□. The specific contact resistance pc of n^+ polysilicon contact to n-type 4H-SiC as low as 3.82 × 10^-5Ω· cm^2 is achieved. The result for sheet resistance Rsh of the phosphorous ion implanted layers in SiC is about 4.9kΩ/□. The mechanisms for n^+ polysilicon ohmic contact to n-type SiC are discussed. 展开更多
关键词 ohmic contact silicon carbide POLYsilicon specific contact resistance P^+ ion implantation
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