中国科学院机构知识库网格系统: 检索

A comparison of the field emission characteristics of vertically aligned graphene sheets grown on different SiC substrates 期刊论文 OAI收割
CHINESE PHYSICS B, 2013, 卷号: 22, 期号: 10
Chen, LL; Guo, LW; Liu, Y; Li, ZL; Huang, J; Lu, W

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field emission vertically aligned graphene sheets SiC substrate

Surface modification of SiC mirror by IARE method (EI CONFERENCE) 会议论文 OAI收割
7th International Conference on Thin Film Physics and Applications, September 24, 2010 - September 27, 2010, Shanghai, China
作者: Gao J.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

A method to prepare high quality SiC coating at low temperature using large aperture E-beam evaporation PVD equipment with ion assistance was developed for the surface modification of SiC mirror for space projects. This method was called Ion Assisted Reactive Evaporation (IARE). The modified SiC coating was prepared using CH4 and Si with Kaufman ion source by IARE at 300C and it had met the requirements of applications. The SiC coating prepared by this method was amorphous. It was dense homogeneous and easy to be polished. The surface modification of a SiC mirror was carried out using SiC coating by this method and achieved a fine surface modification effect. The surface roughness (rms) of the SiC substrate was reduced to 0.862nm the scattering coefficient was reduced to 2.79% and the reflectance coated with Ag film was improved simultaneously after the surface modification. The effect of surface modification using SiC coating was close to that of using Si coating. It can be drawn that this technological method to preparation SiC coating for the surface modification of SiC mirror is reasonable and effective. 2011 SPIE.

Manufacture of 1.2m reaction bonded silicon carbide mirror blank CFID (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China
作者: Zhang G.; Zhang G.; Zhang G.

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Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion high stiffness fine optical quality and dimensional stability make SiC an ideal material for large space born telescope. Since ten years Changchun institute optics fine mechanics and physics (CIOMP) has developed reaction bonded SiC (RB-SiC) technology for space application and can fabricate RB-SiC mirror with scale less than 1.0 meter for telescope. The green body is prepared with gel-casting method which is an attractive new ceramic forming process for making high-quality complex-shaped ceramic parts. And then unmolding drying binder burning out reacting bonded the RB-SiC can be obtained. But with the development of space-born or ground telescope the scale of primary mirror has exceeded 1.0 meter. So CIOMP has developed an assembly technique which called novel reaction-formed joint technology for larger RB-SiC mirror blank. The steps include joining of green bodies with mixture comprised of SiC particles and phenolic resin etc firing machining and sintering. Joining the 1.2 meter RB-SiC mirror blank by the novel reaction-formed joint technology. And testing the welding layer's performance the results show that the thickness of 54-77m the microstructure and thermal property can be comparable to the substrate and the mechanical property are excellent in bending strength of 307MPa. 2010 Copyright SPIE - The International Society for Optical Engineering.

An internally-matched gan hemts device with 45.2 w at 8 ghz for x-band application 期刊论文 iSwitch采集
Solid-state electronics, 2009, 卷号: 53, 期号: 3, 页码: 332-335
作者: Wang, X. L.; Chen, T. S.; Xiao, H. L.; Tang, J.; Ran, J. X.

收藏 | 浏览/下载：28/0 | 提交时间：2019/05/12

Algan/aln/gan Hemt Mocvd Sic substrate Power device

An internally-matched GaN HEMTs device with 45.2 W at 8 GHz for X-band application 期刊论文 OAI收割
SOLID-STATE ELECTRONICS, 2009, 卷号: 53, 期号: 3, 页码: 332-335
作者: Wang, X. L.; Chen, T. S.; Xiao, H. L.; Tang, J.; Ran, J. X.

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收藏 | 浏览/下载：20/0 | 提交时间：2021/02/02

AlGaN/AlN/GaN HEMT MOCVD SiC substrate Power device

IAD-Si coatings on RB-SiC space mirrors for ultra-smooth surfaces (EI CONFERENCE) 会议论文 OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者: Xu L.; Wang X.; Wang X.; Wang X.; Zhang F.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

To eliminate surface limitation caused by Silicon impurity in RB-SiC space mirrors a relatively thick Si film is deposited on well finished RB-SiC substrate by a new process-ion assisted depositing (IAD) to provide a better polishable surface. Testing results of IAD-Si properties are provided showing that the amorphous film has great thermal shock resistance. Then polishing experiments on 100.5m thick IAD-Si layers are accomplished focusing on smoother surface. Surface figure and micro-roughness of the coating after polished reach 0.026 RMS (=0.6328nm) and less than 0.5nm RMS respectively. Moreover reflectivity of IAD-Si polished surface with reflective films increases higher than 4.5% than that of RB-SiC in 360-1100nm. High reflectivity and desirable thermal property make IAD-Si an attractive coating material for RB-SiC space mirrors. 2009 SPIE.

An internally-matched GaN HEMTs device with 45.2 W at 8 GHz for X-band application 期刊论文 OAI收割
solid-state electronics, 2009, 卷号: 53, 期号: 3, 页码: 332-335
作者: Zhang ML; Hou QF

收藏 | 浏览/下载：142/30 | 提交时间：2010/03/08

AlGaN/AlN/GaN HEMT MOCVD SiC substrate Power device

Deposition of thick TiAlN coatings on 2024 Al/SiC(p) substrate by Arc ion plating 期刊论文 OAI收割
Surface & Coatings Technology, 2008, 卷号: 202, 期号: 21, 页码: 5170-5174
S. S. Zhao; H. Du; J. D. Zheng; Y. Yang; W. Wang; J. Gong; C. Sun

收藏 | 浏览/下载：27/0 | 提交时间：2012/04/13

gradient TiAlN coating (ti Al/SiC(p) substrate al)n coatings arc ion plating nitrogen flow rate cathodic vacuum-arc hard coatings cutting tools films pressure performance contact bias

4H-SiC基底Al_2O_3/SiO_2双层减反射膜的设计和制备 期刊论文 OAI收割
光学学报, 2008, 卷号: 28, 期号: 12, 页码: 2431, 2435
黄火林; 张峰; 吴正云; 齐红基; 姚建可; 范正修; 邵建达

收藏 | 浏览/下载：1196/189 | 提交时间：2009/09/22

薄膜光学 Al2O3/SiO2双层减反射膜电子束蒸发 4H-SiC基底折射率 4H-SiC substrate Al2O3/SiO2 double-layer anti-reflection coatings Deposited layers Electron beam evaporation Layer coatings Layer thicknesses Physical thicknesses Reference wavelengths Reflection spectrums Scanning electron microscopes SEM images Single layers Thin film optics UV optoelectronic devices Wavelength selectivities

Fabrication technique of large-scale lightweight SiC space mirror (EI CONFERENCE) 会议论文 OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China
作者: Zhang G.; Zhang G.; Zhang G.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

Silicon carbide (SiC) is a new type candidate material for large-scale lightweight space mirror. Its low thermal distortion high stiffness high optical quality and its dimensional stability are better than other traditional optical substrate materials such as ULE Zerodure Beryllium (Be) and so on. In this paper the lightweight silicon carbide space mirror blank was fabricated by reaction sintering. As a space born mirror material silicon carbide must be an optical grade ceramic. So we prepared the silicon carbide green body with gel-casting method. Then some carbon materials were supplemented into the green body which will bring reaction-sintering with silicon in a vacuum furnace during 1500-1600C ultimately the reaction bonded silicon carbide was made. The diameter of SiC space mirror blank we have made is 680mm. If expanding the size of the vacuum furnace bigger mirror blank can be obtained. The test results show that the mechanical and thermal properties of RB-SiC are excellent with bending strength of 350MPa fracture toughness of 4.1 MPa·m1/2 and coefficient of thermal expansion(CET) of 2.6710-6/K. The surface roughness(RMS) could be better than 3nm.