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三元层状碳化物Ti_3SiC_2的研究进展 被引量:22
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作者 朱教群 梅炳初 陈艳林 《材料科学与工程》 CSCD 北大核心 2001年第4期105-109,共5页
本文综合介绍Ti3SiC2 的最新研究进展。三元碳化物Ti3SiC2 属于层状六方晶体结构 ,空间群为P63 mmC ;它同时具有金属和陶瓷的优良性能 ,有良好的导电和导热能力 ,高弹性模量和低维氏显微硬度 ,在室温下可切削加工 ,在高温下能产生塑性变... 本文综合介绍Ti3SiC2 的最新研究进展。三元碳化物Ti3SiC2 属于层状六方晶体结构 ,空间群为P63 mmC ;它同时具有金属和陶瓷的优良性能 ,有良好的导电和导热能力 ,高弹性模量和低维氏显微硬度 ,在室温下可切削加工 ,在高温下能产生塑性变形 ,良好的高温热稳定性和优秀的抗氧化性能 ;应用CVD、SHS、HP HIP等方法可制备该化合物 ,用HIP方法能制备高纯、致密的Ti3SiC2 陶瓷 ;Ti3SiC2 展开更多
关键词 TI3SIC2 结构 性能 制备 抗损伤机理 三元层状化物 碳硅化 陶瓷材料
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铁素体可锻铸铁的脆性与碳硅比
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作者 王泽书 《铸造》 CAS CSCD 北大核心 1990年第9期29-31,共3页
分析了化学成分(特别是碳与硅关系)与退火工艺、铸件质量间的关系,就可锻铸铁生产中可能发生的脆性提出了解决办法。
关键词 铁素体 可锻 铸铁 脆性 碳硅化
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Ti_(3)SiC_(2)陶瓷材料制备方法研究进展 被引量:1
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作者 孙国栋 康凯 +5 位作者 解静 贾研 郑斌 吕龙飞 田清来 唐宇星 《材料导报》 EI CAS CSCD 北大核心 2024年第18期10-20,共11页
作为MAX相家族重要成员,钛硅化碳Ti_(3)SiC_(2)除了具有耐高温、抗氧化性能外,还具有与金属类似的优异导电性、导热性和可加工性,在电接触材料、热交换器构件材料、润滑材料等领域展现出较大的应用潜力,成为当前一种备受关注的新型陶瓷... 作为MAX相家族重要成员,钛硅化碳Ti_(3)SiC_(2)除了具有耐高温、抗氧化性能外,还具有与金属类似的优异导电性、导热性和可加工性,在电接触材料、热交换器构件材料、润滑材料等领域展现出较大的应用潜力,成为当前一种备受关注的新型陶瓷材料。现有的Ti_(3)SiC_(2)制备方法主要有无压烧结、热压烧结、热等静压、放电等离子烧结、前驱体转换陶瓷、反应熔体浸渗法、熔盐法、化学气相沉积、物理气相沉积等。本文首先阐述了Ti_(3)SiC_(2)材料的结构与性能,然后重点综述了国内外Ti_(3)SiC_(2)陶瓷材料的制备方法,最后展望了Ti_(3)SiC_(2)陶瓷材料的应用前景。 展开更多
关键词 硅化 MAX相 陶瓷材料 制备方法 结构与性能
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层状Ti_3SiC_2陶瓷的组织结构及力学性能 被引量:30
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作者 李世波 成来飞 +1 位作者 王东 张立同 《复合材料学报》 EI CAS CSCD 北大核心 2002年第6期20-24,共5页
 利用热压烧结TiH2,Si和C粉获得了致密度大于98%的层状Ti3SiC2陶瓷。利用压痕法,在不同的载荷下测定了材料的维氏硬度,发现其硬度值随载荷的增加而降低,在最大载荷30kg时,硬度值为4GPa。压痕对角线没有发现径向裂纹的出现。这归因于多...  利用热压烧结TiH2,Si和C粉获得了致密度大于98%的层状Ti3SiC2陶瓷。利用压痕法,在不同的载荷下测定了材料的维氏硬度,发现其硬度值随载荷的增加而降低,在最大载荷30kg时,硬度值为4GPa。压痕对角线没有发现径向裂纹的出现。这归因于多重能量吸收机制——颗粒的层裂、裂纹的扩展、颗粒的变形等。利用三点弯曲法和单边切口梁法测定了材料的强度和韧性分别为270MPa和6.8MPa·m1/2。Ti3SiC2材料的断口表现出明显的层状性质,大颗粒易于发生层裂和穿晶断裂,小颗粒易被拔出。当裂纹沿平行于Ti3SiC2基面的方向扩展造成颗粒的层裂,当裂纹沿垂直于基面的方向扩展时,裂纹穿过颗粒的同时,在颗粒内部发生偏转,使裂纹的扩展路径增加。裂纹的扩展路径类似人们根据仿生结构设计的层状复合材料。裂纹在颗粒内的多次偏转、裂纹钉扎以及颗粒的层裂和拔出等是材料韧性提高的主要原因。此外,在室温下得到的荷载-位移曲线,说明Ti3SiC2材料不象其它陶瓷材料的脆性断裂,而是具有金属一样的塑性。 展开更多
关键词 层状Ti3SiC2陶瓷 组织结构 力学性能 增韧机制 碳硅化 结构陶瓷
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Reduced graphene oxide porous films containing SiC whiskers for constructing multilayer electromagnetic shields
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作者 LI Jing Qi Yi-quan +3 位作者 ZHAO Shi-xiang QIU Han-xun YANG Jun-he YANG Guang-zhi 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第6期1191-1201,共11页
Developing lightweight and flexible thin films for electromagnetic interference(EMI)shielding is of great importance.Porous thin films of reduced graphene oxide containing SiC whiskers(SiC@RGO)for EMI shielding were p... Developing lightweight and flexible thin films for electromagnetic interference(EMI)shielding is of great importance.Porous thin films of reduced graphene oxide containing SiC whiskers(SiC@RGO)for EMI shielding were prepared by a two-step reduction of graphene oxide(GO),in which the two steps were chemical reduction by HI and the solid phase microwave irradiation.A significant increase of the film thickness from around 20 to 200μm was achieved due to the formation of a porous structure by gases released during the 3 s of solid phase microwave irradiation.The total shielding effectiveness(SET)and the reflective SE(SE_(R))of the SiC@RGO porous thin films depended on the GO/SiC mass ratio.The highest SET achieved was 35.6 dB while the SE_(R) was only 2.8 dB,when the GO/SiC mass ratio was 4∶1.The addition of SiC whiskers was critical for the multi-reflection,interfacial po-larization and dielectric attenuation of EM waves.A multilayer film with a gradient change of SE values was constructed using SiC@RGO porous films and multi-walled carbon nanotubes buckypapers.The highest SET of the multilayer films reached 75.1 dB with a SE_(R) of 2.7 dB for a film thickness of about 1.5 mm.These porous SiC@RGO thin films should find use in multilayer or sand-wich structures for EMI absorption in packaging or lining. 展开更多
关键词 GRAPHENE Thin films Silicon carbide whiskers Electromagnetic interference shielding
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放电等离子烧结工艺合成Ti_3SiC_2的研究 被引量:14
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作者 朱教群 梅炳初 陈艳林 《硅酸盐学报》 EI CAS CSCD 北大核心 2002年第5期649-652,共4页
以元素单质粉为原料 ,当原料配比为n(Ti)∶n(Si)∶n(Al)∶n(C) =3∶(1.2 -x)∶x∶2 ,其中 :x =0 .0 5~ 0 .2时 ,在 12 0 0~ 12 5 0℃温度下经放电等离子烧结成功制备了高纯、致密Ti3SiC2 固溶体材料。原料中掺加适量Al能改善Ti3SiC2 ... 以元素单质粉为原料 ,当原料配比为n(Ti)∶n(Si)∶n(Al)∶n(C) =3∶(1.2 -x)∶x∶2 ,其中 :x =0 .0 5~ 0 .2时 ,在 12 0 0~ 12 5 0℃温度下经放电等离子烧结成功制备了高纯、致密Ti3SiC2 固溶体材料。原料中掺加适量Al能改善Ti3SiC2 的合成反应并提高制备材料的纯度。当x =0 .2时 ,所合成的固溶体形貌为板状结晶 ,分子式近似为Ti3Si0 .8Al0 .2 C2 ,晶格参数a =0 .3 0 69nm ,c=1.767nm。在 12 5 0℃温度下烧结 ,得到平均厚度达 5 μm ,发育完善均匀的致密多晶体材料。材料Vickers硬度为 3 .5~ 5 .5GPa 。 展开更多
关键词 放电等离子烧结工艺 合成 TI3SIC2 研究 碳硅化
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Performance of Lateral 4H-SiC Photoconductive Semiconductor Switches by Extrinsic Backside Trigger
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作者 WANG Hao LIU Xuechao +8 位作者 ZHENG Zhong PAN Xiuhong XU Jintao ZHU Xinfeng CHEN Kun DENG Weijie TANG Meibo GUO Hui GAO Pan 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第9期1070-1076,共7页
Photoconductive semiconductor switch(PCSS)can be applied in pulsed high power systems and microwave techniques.However,reducing the damage and increasing the lifetime of silicon carbide(SiC)PCSS are still faced severe... Photoconductive semiconductor switch(PCSS)can be applied in pulsed high power systems and microwave techniques.However,reducing the damage and increasing the lifetime of silicon carbide(SiC)PCSS are still faced severe challenges.In this study,PCSSs with various structures were prepared on 4-inch diameter,500μm thick high-purity semi-insulating 4H-SiC substrates and their on-state resistance and damage mechanisms were investigated.It was found that the PCSS of an Au/TiW/Ni electrode system annealed at 950℃had a minimum on-state resistance of 6.0Ωat 1 kV bias voltage with a 532 nm and 170 mJ pulsed laser by backside illumination single trigger.The backside illumination single trigger could reduce on-state resistance and alleviate the damage of PCSS compared to the frontside trigger when the diameter of the laser spot was larger than the channel length of PCSS.For the 200 s trigger test by a 10 Hz laser,the black branch-like ablation on Au/TiW/Ni PCSS was mainly caused by thermal stress owing to hot carriers.Replacing metal Ni with boron gallium co-doped zinc oxide(BGZO)thin films annealed at 400℃,black branch-like ablation was alleviated while concentric arc damage was obvious at the anode.The major causes of concentric arc are both pulsed laser diffraction and thermal effect. 展开更多
关键词 silicon carbide photoconductive semiconductor switch on-state resistance failure analysis
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Increasing both the electromagnetic shielding and thermal conductive properties of three-dimensional graphene-CNT-SiC hybrid materials
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作者 FENG Fan HAN Zhi-dong +4 位作者 WEI Bing WANG Yang WANG Fei-zhou JIAO Yan-yan WANG Zhen-ting 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第6期1178-1190,共13页
During the operation of electronic devices,a considerable amount of heat and electromagnetic radiation is emitted.Therefore,the investigation of materials with electromagnetic shielding and thermal management abilitie... During the operation of electronic devices,a considerable amount of heat and electromagnetic radiation is emitted.Therefore,the investigation of materials with electromagnetic shielding and thermal management abilities has significant importance.Hybrid materials of three-dimensional graphene networks containing both carbon nanotubes(CNTs)and SiC whiskers(3D graphene-CNT-SiC)were synthesized.Using an aqueous-phase reduction method for the self-assembly of the graphene oxide,a three-dimen-sional porous graphene structure was fabricated.SiC whiskers,inserted between the graphene layers,formed a framework for longit-udinal thermal conduction,while CNTs attached to the SiC surface,created a dendritic structure that increased the bonding between the SiC whiskers and graphene,improving dielectric loss and thermal conductivity.It was found that the thermal conductivity of the hybrid material reached 123 W·m^(-1)·K^(-1),with a shielding effectiveness of 29.3 dB when the SiC addition was 2%.This result indic-ates that 3D graphene-CNT-SiC has excellent thermal conductivity and electromagnetic shielding performance. 展开更多
关键词 Thermal management Electromagnetic Shielding 3D graphene Silicon carbide Carbon nanotubes
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放电等离子烧结制备Ti_3SiC_2材料的研究 被引量:9
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作者 朱教群 梅炳初 陈艳林 《材料科学与工程》 CSCD 北大核心 2002年第4期564-567,共4页
本文报道分别以Ti Si C ,Ti SiC C为原料 ,采用放电等离子烧结工艺制备Ti3SiC2 材料的研究结果。以元素单质粉为原料 ,掺加适量Al作助剂能加速Ti3SiC2 的反应合成并提高材料的纯度 ,在 12 0 0~ 12 5 0℃的温度下能制备出经XRD、SME和ED... 本文报道分别以Ti Si C ,Ti SiC C为原料 ,采用放电等离子烧结工艺制备Ti3SiC2 材料的研究结果。以元素单质粉为原料 ,掺加适量Al作助剂能加速Ti3SiC2 的反应合成并提高材料的纯度 ,在 12 0 0~ 12 5 0℃的温度下能制备出经XRD、SME和EDS表征不含TiC和SiC等杂质相的纯净Ti3SiC2 材料。而以Ti SiC C为原料时 ,有无Al作助剂都难以制备出纯净的Ti3SiC2 。 展开更多
关键词 Ti3SiC2材料 碳硅化 制备 放电等离子烧结 原料
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用热压法制备Ti_3SiC_2层状陶瓷的研究 被引量:8
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作者 陈艳林 梅炳初 朱教群 《陶瓷学报》 CAS 2004年第1期55-59,共5页
以TiC/Si/Al/Ti为原料 ,采用热压工艺制备出高纯致密的块体材料 ,合成材料的X -射线 ,扫描电镜 (SEM)结合能谱仪 (EDS)分析结果表明 :当烧结温度为 14 0 0℃时 ,合成样品纯度为 98.2 %,晶格参数为a =0 .3 0 69nm ,c =1.767nm ,晶粒尺寸... 以TiC/Si/Al/Ti为原料 ,采用热压工艺制备出高纯致密的块体材料 ,合成材料的X -射线 ,扫描电镜 (SEM)结合能谱仪 (EDS)分析结果表明 :当烧结温度为 14 0 0℃时 ,合成样品纯度为 98.2 %,晶格参数为a =0 .3 0 69nm ,c =1.767nm ,晶粒尺寸为 4~ 10 μm的板状结晶。 展开更多
关键词 碳硅化 合成 热压烧结 制备 层状陶瓷
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放电等离子烧结含铝Ti_3SiC_2相的形成规律研究 被引量:3
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作者 朱教群 梅炳初 陈艳林 《武汉理工大学学报》 CAS CSCD 2003年第4期5-7,共3页
用放电等离子烧结工艺以元素粉为原料制备 Ti3Si C2 材料时 ,掺入适量铝能改善 Ti3Si C2 的反应合成。应用 X-射线衍射和扫描电子显微镜研究不同烧结温度下材料的相组成和显微结构特征。结果表明 :含铝 Ti3Si C2 相在 110 0℃开始大量形... 用放电等离子烧结工艺以元素粉为原料制备 Ti3Si C2 材料时 ,掺入适量铝能改善 Ti3Si C2 的反应合成。应用 X-射线衍射和扫描电子显微镜研究不同烧结温度下材料的相组成和显微结构特征。结果表明 :含铝 Ti3Si C2 相在 110 0℃开始大量形成 ,经 115 0~ 12 5 0℃烧结 ,能制备纯净致密含铝 Ti3Si C2 固溶体材料。铝的固溶降低了 Ti3Si C2 的化学热稳定性 ,使其分解温度降低至 130 0℃。 展开更多
关键词 碳硅化 形成规律 放电等离子烧结 过程参数
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S-Band 1mm SiC MESFET with 2W Output on Semi-Insulated SiC Substrate 被引量:5
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作者 蔡树军 潘宏菽 +2 位作者 陈昊 李亮 赵正平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期266-269,共4页
A SiC MESFET structure is successfully prepared on a semi-insulated 50mm SiC substrate using a hotwall SiC reactor. The doping concentration for the channel layer is about 1.7 × 10^17 cm^-3 , and the thickness is... A SiC MESFET structure is successfully prepared on a semi-insulated 50mm SiC substrate using a hotwall SiC reactor. The doping concentration for the channel layer is about 1.7 × 10^17 cm^-3 , and the thickness is about 0.35μm. An unintentionally n-doped buffer layer is employed between the substrate and the channel layer. A cap layer for Ohmic contact is doped to 10^19cm^-3. MESFET devices are fabricated using inductively coupled plasma etching and other conventional tools. Power devices with a 1mm gate width are measured and a 2W output at 2GHz is obtained. 展开更多
关键词 MESFET SiC buffer layer
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Fabrication of SiC fibres from yttrium-containing polycarbosilane 被引量:4
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作者 杨大祥 宋永才 +2 位作者 余煜玺 赵晓峰 肖平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期879-886,共8页
The yttrium as a sintering aid was introduced into polycarbosilane(PCS) to prepare yttrium-containing PCS(PYCS).Two types of yttrium-containing SiC fibres,the SiC(OY) fibres and the SiC(Y) fibres,were fabricat... The yttrium as a sintering aid was introduced into polycarbosilane(PCS) to prepare yttrium-containing PCS(PYCS).Two types of yttrium-containing SiC fibres,the SiC(OY) fibres and the SiC(Y) fibres,were fabricated with PYCS.The structural evolution and the associated properties on changing from SiC(OY) to SiC(Y) fibres during the sintering process were studied.The chemical composition of the SiC(OY) fibres is SiC1.53O0.22Y0.005 with an amorphous structure.The composition of SiC(Y) fibres is SiC1.23O0.05Y0.005.The fibres are composed of a large number of β-SiC crystallites with a size of 50 nm and a small amount of α-SiC crystalline.The tensile strength and fracture toughness of the SiC(OY) fibres are 2.25 GPa and 2.37 MPa·m1/2,respectively,and 1.61 GPa,1.91 MPa·m1/2,respectively for SiC(Y) fibres.The SiC(Y) fibres have a higher thermal stability than the SiC(OY) fibres. 展开更多
关键词 POLYCARBOSILANE YTTRIUM silicon carbide FIBRE
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Ti_3Si_((1-x))Al_xC_2在900℃~1300℃空气中的氧化行为 被引量:5
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作者 梅炳初 徐学文 +1 位作者 朱教群 刘俊 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2005年第6期895-898,共4页
  热压摩尔比为n(TiC):n(Ti):n(Si):n(Al)=2:1:1:0.2混合粉末制备的Ti3Si(1-x)AlxC2(0<x≤0.16)材料在900℃-1300℃空气中的恒温氧化行为遵循抛物线规律,但在1200℃和1300℃是一个两步抛物线过程。随着温度升高,氧化抛物线速率常...   热压摩尔比为n(TiC):n(Ti):n(Si):n(Al)=2:1:1:0.2混合粉末制备的Ti3Si(1-x)AlxC2(0<x≤0.16)材料在900℃-1300℃空气中的恒温氧化行为遵循抛物线规律,但在1200℃和1300℃是一个两步抛物线过程。随着温度升高,氧化抛物线速率常数kp从900℃的2.45×10-10kg2·m-4·s-1增大到1300℃的5.71×10-9kg2·m-4·s-1,计算的氧化活化能为110kJ·mol-1±10kJ·mol-1。弥散分布在基体中的Al改变了Ti3SiC2材料的氧化机制,使试样表面形成由大量α-Al2O3和少量TiO2与SiO2组成的致密氧化层,从而提高了材料的抗氧化性。 展开更多
关键词 硅化 氧化性能 动力学
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氩离子轰击对射频溅射法制备的a-SiC∶H膜退火形成6H-SiC的影响 被引量:9
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作者 王辉耀 王印月 +1 位作者 宋青 王天民 《Journal of Semiconductors》 EI CAS CSCD 北大核心 1998年第8期569-573,共5页
本文对射频溅射法淀积的a-SiC∶H膜热退火形成6H-SiC相进行了研究.我们采用红外透射谱、喇曼背散射谱和X光衍射谱来研究退火形成6H-SiC的过程.在较高的射频功率下淀积的a-SiC∶H膜经800℃60分钟等时退... 本文对射频溅射法淀积的a-SiC∶H膜热退火形成6H-SiC相进行了研究.我们采用红外透射谱、喇曼背散射谱和X光衍射谱来研究退火形成6H-SiC的过程.在较高的射频功率下淀积的a-SiC∶H膜经800℃60分钟等时退火后转变为6H-SiC相,该温度低于在低功率下制备的a-SiC∶H形成6H-SiC的温度(1000℃).高功率可导致6H-SiC形成温度的降低与膜中硅及石墨团簇的消失,同时高能量的氩离子轰击可使膜中氢含量减少及各组分均相.通过改变射频功率,本文研究了氩离子轰击对a-SiC∶H膜及形成6H-SiC的影响. 展开更多
关键词 硅化 氩离子轰击 退火 射频溅射法
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Nanogrinding of SiC wafers with high flatness and low subsurface damage 被引量:8
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作者 霍凤伟 郭东明 +1 位作者 康仁科 冯光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期3027-3033,共7页
Nanogrinding of SiC wafers with high flatness and low subsurface damage was proposed and nanogrinding experiments were carried out on an ultra precision grinding machine with fine diamond wheels. Experimental results ... Nanogrinding of SiC wafers with high flatness and low subsurface damage was proposed and nanogrinding experiments were carried out on an ultra precision grinding machine with fine diamond wheels. Experimental results show that nanogrinding can produce flatness less than 1.0μm and a surface roughness Ra of 0.42nm. It is found that nanogrinding is capable of producing much flatter SiC wafers with a lower damage than double side lapping and mechanical polishing in much less time and it can replace double side lapping and mechanical polishing and reduce the removal amount of chemical mechanical polishing. 展开更多
关键词 SiC wafer nanogrinding cup wheel FLATNESS surface roughness DAMAGE
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MOCVD-Grown AlGaN/AlN/GaN HEMT Structure with High Mobility GaN Thin Layer as Channel on SiC 被引量:3
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作者 王晓亮 胡国新 +9 位作者 马志勇 肖红领 王翠梅 罗卫军 刘新宇 陈晓娟 李建平 李晋闽 钱鹤 王占国 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第9期1521-1525,共5页
AlGaN/AlN/GaN high electron mobility transistor (HEMT) structures with a high-mobility GaN thin layer as a channel are grown on high resistive 6H-SiC substrates by metalorganic chemical vapor deposition. The HEMT st... AlGaN/AlN/GaN high electron mobility transistor (HEMT) structures with a high-mobility GaN thin layer as a channel are grown on high resistive 6H-SiC substrates by metalorganic chemical vapor deposition. The HEMT structure exhibits a typical two-dimensional electron gas (2DEG) mobility of 1944cm^2/(V·s) at room temperature and 11588cm^2/(V ·s) at 80K with almost equal 2DEG concentrations of about 1.03 × 10^13 cm^-2. High crystal quality of the HEMT structures is confirmed by triple-crystal X-ray diffraction analysis. Atomic force microscopy measurements reveal a smooth AlGaN surface with a root-mean-square roughness of 0.27nm for a scan area of 10μm × 10μm. HEMT devices with 0.8μm gate length and 1.2mm gate width are fabricated using the structures. A maximum drain current density of 957mA/mm and an extrinsic transconductance of 267mS/mm are obtained. 展开更多
关键词 A GaN/GaN HEMT MOCVD power device SiC substrates
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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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Improved Epitaxy of 3C-SiC Layers on Si(100) by New CVD/LPCVD System 被引量:1
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作者 孙国胜 王雷 +5 位作者 罗木昌 赵万顺 孙殿照 曾一平 李晋闽 林兰英 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第8期800-804,共5页
Single crystalline 3C-SiC epitaxial layers are grown on φ 50mm Si wafers by a new resistively heated CVD/LPCVD system,using SiH_4,C_2H_4 and H_2 as gas precursors.X-ray diffraction and Raman scattering measurements a... Single crystalline 3C-SiC epitaxial layers are grown on φ 50mm Si wafers by a new resistively heated CVD/LPCVD system,using SiH_4,C_2H_4 and H_2 as gas precursors.X-ray diffraction and Raman scattering measurements are used to investigate the crystallinity of the grown films.Electrical properties of the epitaxial 3C-SiC layers with thickness of 1~3μm are measured by Van der Pauw method.The improved Hall mobility reaches the highest value of 470cm 2/(V·s) at the carrier concentration of 7.7×10 17 cm -3 . 展开更多
关键词 CVD/LPCVD HETEROEPITAXY 3C-SIC
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Fabrication of SiC MESFETs for Microwave Power Applications 被引量:1
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作者 柏松 陈刚 +5 位作者 张涛 李哲洋 汪浩 蒋幼泉 韩春林 陈辰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第1期10-13,共4页
4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation.... 4H-SiC MESFETs are fabricated on semi-insulating SiC substrates. Key processes are optimized to obtain better device performance. A microwave power amplifier is demonstrated from a 1mm SiC MESFET for S band operation. When operated at a drain voltage of 64V, the amplifier shows an output power of 4.09W, a gain of 9.3dB,and a power added efficiency of 31.3%. 展开更多
关键词 4H-SIC MESFET MICROWAVE power amplifier
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