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Microstructure of Differently Annealed NanocrystallineFe_(72.7)Cu_1Nb_(1.8)Mo_2si_(13)B_(9.5) Alloy

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Journal of Materials Science & Technology 1998年第4期14卷 327-330页

作者： YanZhong ZHANG and Huijuan JIN (Shanghai Key Lab. of Metallic Functional Materials, Shanghai Iron and Steel Research Institute,Shanghai 200940, China) Shanghai Key Lab. of Metallic Functional Materials Shanghai Iron and Steel Research Institute Shanghai 200940 China

The microstructure of differently annealed nanocrystalline Fe72.7Cu1Nb1.8Mo2si13B9.5 alloy was investigated by using Mssbauer spectroscopy and transmission electron microscope. The specimens were isochronally annealed at temperatures between 480℃ and 600℃ for 0.5 h. The experimental results show that the microstructure mainly consists of the nanoscale bcc α-Fe(si) grains and the residual amorphous matrix phase. A trace paramagnetic phase was found for annealing about above 500℃. The volume fraction of cr-Fe(si) grain increases with increasing annealing temperature, whereas the average size of grain is almost unchanged above 480℃ up to 580℃. The calculated thickness of the intergranular layer of the residual amorphous matrix clearly decreases with increasing annealing temperature.

关键词： Mo2si Microstructure of Differently Annealed NanocrystallineFe si Alloy Cu1Nb

Difference in electron-and gamma-irradiation effects on output characteristic of color CMOS digital image sensors

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Rare Metals 2004年第2期23卷 165-170页

作者： MENGXiangti KANGAiguo ZHANGXimin LIJihong HUANGQiang LIFengmei LIUXiaoguang ZHOUHongyu InstituteofNuclearEnergyTechnology TsinghuaUniversityBeijing100084China InstituteofLowEnergyNuclearPhysics BeijingNormalUniversityBeijing100875China

Changes of the average brightness and non-uniformity of dark output images,and quality of pictures captured under natural lighting for the color CMOS digital image sensorsirradiated at different electron doses have been studied in comparison to those from theγ-irradiated sensors. For the electron-irradiated sensors, the non-uniformity increases obviouslyand a small bright region on the dark image appears at the dose of 0.4 kGy. The average brightnessincreases at 0.4 kGy, increases sharply at 0.5 kGy. The picture is very blurry only at 0.6 kGy,showing the sensor undergoes severe performance degradation. Electron radiation damage is much moresevere than γ radiation damage for the CMOS image sensors. A possible explanation is presented inthis paper.

关键词： semiconductor technology irradiation damage electron and gamma irradiation color CMOS image sensor output characteristic si

Influence of Al Preflow Time on Surface Morphology and Quality of AlN and GaN on si(111) Grown by MOCVD

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Chinese Physics Letters 2017年第5期34卷 119-123页

作者：刘波亭马平李喜林王军喜李晋闽 Semiconductor Lighting R&D Center Institute of SemiconductorsChinese Academy of SciencesBeijing 100083 College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049 State Key Laboratory of Solid State Lighting Beijing 100083 Beijing Engineering Research Center for the Third-Generation Semiconductor Materials and Application Beijing 100083

We investigate the influence of A1 preflow time on surface morphology and quality of AIN and GaN. The AIN and GaN layers are grown on a si （111） substrate by metal organic chemical vapor deposition. Scanning electron microscopy, atomic force microscopy, x-ray diffraction and optical microscopy are used for analysis. Consequently, we find significant differences in the epitaxial properties of AlN buffer and the GaN layer, which are dependent on the AI preflow time. A1 preflow layers act as nucleation sites in the case of AiN growth. Compact and uniform AIN nucleation sites are observed with optimizing A1 preflow at an early nucleation stage, which will lead to a smooth AIN surface. Trenches and AlN grain clusters appear on the AIN surface while meltoback etching occurs on the GaN surface with excessive A1 preflow. The GaN quality variation keeps a similar trend with the AIN quality, which is influenced by AI preflow. With an optimized duration orAl preflow, crystal quality and surface morphology of AIN and GaN could be improved.

关键词： GaN AlN AIN Grown by MOCVD Influence of Al Preflow Time on Surface Morphology and Quality of AlN and GaN on si si

Temperature-Dependent Photoluminescence Characteristics of InAs/GaAs Quantum Dots Directly Grown on si Substrates

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Chinese Physics Letters 2016年第4期33卷 52-55页

作者：王霆刘会赟张建军 Institute of Physics Chinese Academy of Sciences Department of Electronic & Electrical Engineering University College London

The first operation of an electrically pumped 1.3μm InAs/GaAs quantum-dot laser was previously reported epitaxially grown on si （100） substrate. Here the direct epitaxial growth condition of 1.3μm InAs/OaAs quantum on a si substrate is further investigated using atomic force microscopy, etch pit density and temperature-dependent photoluminescence （PL） measurements. The PL for si-based InAs/GaAs quantum dots appears to be very sensitive to the initial OaAs nucleation temperature and thickness with strongest room-temperature emission at 40000 （17Onto nucleation layer thickness）, due to the lower density of defects generated under this growth condition, and stronger carrier confinement within the quantum dots.

关键词： GaAs InAs Temperature-Dependent Photoluminescence Characteristics of InAs/GaAs Quantum Dots Directly Grown on si Substrates of si on

The Efficiency Droop of InGaN-Based Green LEDs with Different Superlattice Growth Temperatures on si Substrates via Temperature-Dependent Electroluminescence

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Chinese Physics Letters 2017年第7期34卷 224-227页

作者：齐维靖徐龙权莫春兰王小兰丁杰王光绪潘拴张建立吴小明刘军林江风益 National Institute of LED on si Substrate Nanchang University Nanchang 330047

InGaN-based green light-emitting diodes （LEDs） with different growth temperatures of superlattice grown on si （111） substrates are investigated by temperature-dependent electroluminescence between 100 K and 350K. It is observed that with the decrease of the growth temperature of the superlattice from 895℃ to 855℃, the forward voltage decreases, especially at low temperature. We presume that this is due to the existence of the larger average size of V-shaped pits, which is determined by secondary ion mass spectrometer measurements. Meanwhile, the sample with higher growth temperature of superlattice shows a severer efficiency droop at cryogenic temperatures （about 100 K-150 K）. Electron overflow into p-GaN is considered to be the cause of such phenomena, which is relevant to the poorer hole injection into multiple quantum wells and the more reduced effective active volume in the active region.

关键词： InGaN The Efficiency Droop of InGaN-Based Green LEDs with Different Superlattice Growth Temperatures on si Substrates via Temperature-Dependent Electroluminescence si

Ab Initio Study of the Dynamical si-O Bond Breaking Event in α-Quartz

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Chinese Physics Letters 2015年第10期32卷 130-133页

作者：苏锐张红韩伟陈军 College of Physical Science and Technology Sichuan University Chengdu 610064 Research Center of Laser Fusion Mianyang 621900 Institute of Applied Physics and Computational Mathematics Beijing 100094 Center for Applied Physics and Technology Peking University Beijing 100871

The si-O bond breaking event in the a-quartz at the first triplet （T1） excitation state is studied by using ab initio molecular dynamics （AIMD） and nudged elastic band calculations. A meta-stable non-bridging oxygen hole center and E1 center （NBOHC-E） is observed in the AIMD which consists of a broken si-O bond with a si-O distance of 2.54A. By disallowing the re-bonding of the si and 0 atoms, another defect configuration （lll- si/V-si） is obtained and validated to be stable at both ground and excitation states. The NBOHC-E is found to present on the minimal energy pathway of the initial to IlI-si/V-si transition, showing that the generating of the NBOHC-E is an important step of the excitation induced structure defect. The energy barriers to produce the NBQHC-E＇ and Ⅲ-si/V-si defects are calculated to be 1.19 and 1.28eV, respectively. The electronic structures of the two defects are calculated by the self-consistent GW calculations and the results show a clear electron transition from the bonding orbital to the non-bonding orbital.

关键词： si length Quartz Ab Initio Study of the Dynamical si-O Bond Breaking Event in

Temperature Dependent Work-hardening Behaviour in an Fe-Mn-si-Cr-Ni Shape Memory Alloy

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Journal of Materials Science & Technology 1995年第4期11卷 304-306页

作者： Lijian RONG Yiyi LI and Changxu SHI (Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110015, China) Inst of Metal Research Chinese Acad of Sciences Shenyang China

The work-hardening behaviour in an Fe-Mn-si-Cr-Ni alloy has been investigated using tensile test at different temperatures and TEM observation. It was found that besides the intersection of εmartensite, the intersections of ε martensite with stacking fault and the cross-slip of dislocation which is difficult to occur in the alloy with low stacking fault energy are also important factors to the temperature dependent work-hardening behaviour.

关键词： Work Mn Fe Temperature Dependent Work-hardening Behaviour in an Fe-Mn-si-Cr-Ni Shape Memory Alloy Cr si Ni

MICROSTRUCTURES AND MECHANICAL PROPERTIES OF RAPIDLY SOLIDIFIED Al-Fe-Cr-Zr-V-si ALLOY AND THEIR THERMAL STABILITY

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中国有色金属学会会刊：英文版 1998年第3期8卷 122-125页

作者： Xiao, Yude Li, Songrui Li, Wenxian Wang, Richu Central South Univ of Technology Changsha China

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关键词： rapid solidification powder metallurgy heat resistant aluminium alloy Al Fe Cr Zr V si

Hydrogen Permeation and Diffusion in Amorphous Alloy Ni_(68)Cr7_si_8B_(14)Fe_3 at Elevated Temperature

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Journal of Materials Science & Technology 1997年第5期13卷 443-445页

作者： Wu Q. Xu J. Sun X. Hu Z. National Key Lab. for RSA Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The behaviour of hydrogen permeation and diffusion in amorphous alloy Ni68Cr7si8B14Fe3 hasbeen investigated by an ultrahigh vacuum gas permeation technique. A comparison experimentwas carried out between the as-quenched and annealed States (400℃/2h) of the amorphousalloy. The results show that, for both states of the amorphous alloy in the temperature rangeof 200～350℃, the diffusivity and permeability of hydrogen are in agreement with Arrheniusrelationship, there does not exist H-trapping effect, and the activation energies of diffusion andpermeation almost keep the same.

关键词： Fe3 at Elevated Temperature si Cr7si8B Hydrogen Permeation and Diffusion in Amorphous Alloy Ni