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Fast pore etching on high resistivity n-type silicon via photoelectrochemistry

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Chinese Physics B 2009年第2期18卷 664-670页

作者：包晓清葛道晗张圣李金鹏周萍焦继伟王跃林 State key laboratories of Transducer Technology National Key Laboratories of Microsystem Technology Shanghai Institute of Microsystem and Information Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences

In this paper, five factors, namely the HF （hydrofluoric acid） concentration, field strength, illumination intensity as well as the oxidizing-power and conductivity of electrolytes were found to strongly affect the fast pore etching. The oxidizing power of aqueous HF electrolyte of different concentrations was especially measured and analysed. A positive correlation between optimal bias and HF concentration was generally observed and the relationship was semiquantitatively interpreted. Pore density notably increased with enhanced HF-concentration or bias even on patterned substrates where 2D （two-dimensional） nuclei were densely pre-textured. The etch rate can reach 400μm/h and the aspect ratio of pores can be readily driven up to 250.

关键词： pore density SCR width H-passivation current-burst-model breakdown mechanism

Observation of a diverse deviation from macropore-formation theory in silicon electrochemistry

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Chinese Physics B 2008年第8期17卷 3130-3137页

作者：包晓清葛道晗焦继伟 State key laboratories of Transducer Technology National Key Laboratories of Microsystem Technology Shanghai Institute of Microsystem and Information Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences

Via anodizing patterned and unpatterned samples with a high HF concentration （[HF]）, the degree of deviation from pore-formation theory was found to be markedly different. Based on the analysis of scanning electron microscope （SEM） micrographs and current-voltage （I - V） curves, the variation of physical and chemical parameters of patterned and unpatterned substrates was found to be crucial to the understanding of the observations. Our results indicate that the initial surface morphology of samples can have a considerable influence upon pore formation. The electric-field effect as well as current-burst-model was employed to interpret the underlying mechanism.

关键词： space charge region point nuclei unpatterned specimen I - V curve

Development of a Non-Contact Electromagnetic Surface Velocity Sensor for Molten Metal Flow

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Journal of Iron and Steel Research International 2012年第S1期19卷 509-513页

作者： JIAN Dan-dan KARCHER Christian XU Xiu-jie DENG An-yuan WANG En-gang THESS André Ilmenau University of Technology Institute of Thermodynamics and Fluid MechanicsIlmenau 100565Germany key laboratories on epm Ministry of ScienceNortheastern University

During continuous casting of steel,knowledge of both direction and magnitude of the velocity at the mold surface is of special ***,the surface is covered by a non-transparent layer of mold powder to prevent formation of ***,this meniscus flow cannot be registered by optical measurement ***-contact measurement methods are of *** of such non-invasive techniques is Lorentz force veloeimetry(LFV).It is based on measuring the electromagnetically induced force acting on a magnet *** this paper we present a series of experiments that aim to demonstrate the feasibility of using two identical velocimeters,termed Time-of-Flight LFV(ToF LFV).Using ToF LFV the free-surface velocity may be purely determined by cross-correlating the two force signals delivered by the two force *** have developed a special prototype of such a measuring device termed meniscus velocity sensor(MVS).It has been designed to record local surface velocities in high-temperature metal *** Ilmenau University of Technology,the method has been successfully tested using both solid body movement and Ga^(68%)In^(20%)Sn^(12%)as a low-melting model *** the present paper we apply this technique to the case of high-temperature metal *** more detail,we present test measurements under industry-relevant conditions using both Sn^(32%)pb^(52%)Bi at 210℃ and molten steel at about 1700℃.These experiments were conducted at key laboratories on epm at North Eastern *** evaluation of the data shows that our prototype of MVS works well in producing reproducible signals of which surface velocity can be determined.

关键词： free-surface liquid melt flow Lorentz force velocimetry magnetohydrodynamics

Influence of Orthorhombic-Tetragonal Phase Transition on Microwave Dielectric Dispersion of BaTiO3 Ceramic

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Chinese Physics Letters 2013年第12期30卷 144-147页

作者： HAO Wen-Tao ZHANG Jia-Liang ZHENG Peng WU Yan-Qing TAN Yong-Qiang ZHAO Xu School of Physics State Key Laboratories of Crystal MaterialsShandong UniversityJinan 250100

The temperature evolution of dielectric dispersion is examined for a coarse-grained BaTiO_(3)ceramic in the frequency range from 40 Hz to 1 GHz and over the temperature interval between-50℃and 80℃,which thus includes the orthorhombic-tetragonal phase transition and covers the large part of common usage temperature *** find an important physical phenomenon that the phase transition has a notable influence on the microwave dielectric *** dielectric permittivityε'shows a maximum,whereas the characteristic frequency fr displays a minimum in the vicinity of orthorhombic-tetragonal phase transition ***,a large difference in the fr values is observed in the tetragonal phase between the heating process and the cooling *** seems that the experimentally found phenomenon can be explained by the previously suggested mechanism of the emission of elastic shear waves from ferroelastic domain walls.

关键词： ceramic dielectric Dispersion

Effect of Boron Concentration on Dynamic Recrystallization Behavior of Low-Carbon Steel

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 931-939页

作者： Yong-Liang Gao Xiang-Xin Xue He Yang Liaoning key laboratories of Ecological Utilization Technology of Boron Resources and Boron Materials Northeastern University

The dynamic recrystallization behavior of low-carbon steel containing three different amounts of boron（0.002,0.004,and 0.006 wt%） was systematically investigated under various experimental ***-carbon steel was exposed to temperatures ranging from 900 to 1100 ℃,strain rates from 0.1 to 10 s^-1,and inspection of the initial austenite grain size at 1150℃.The resulting stress–strain curves are observed to possess two classifications of behavior,dynamic recovery and dynamic recrystallization,while the initial austenite grain size increases directly proportional to boron ***,the characteristic points of the flow curves were analyzed by regression method in which the peak and critical stresses decreased in response to an increase in boron composition,indicating that a softening effect appears with the addition of *** the contrary,peak and critical strains increased as boron content increased,indicating that boron has the ability to delay the onset of dynamic ***,the kinetics model of dynamic recrystallization for three boron-treated steels was established.

关键词： Boron-treated steel Hot deformation Flow stress Dynamic recrystallization

A K-/Ka-band planar shared-aperture beam-scanning array with a high-isolation for the emerging mm-Wave shared-aperture terminals

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Science China(Information Sciences) 2023年第5期66卷 257-270页

作者： Zi-Jun GUO Zhang-Cheng HAO Zhuo-Wei MIAO Hao-Yu YIN Chen-Yu DING Hao-Jie GANG State key Laboratory of Millimeter Waves School of Information Science and Engineering Southeast University Purple Mountain laboratories

A planar K-/Ka-band shared-aperture array with the steerable beam is proposed in this paper. The substrate-integrated coaxial line(SICL)-excited short-circuited-stub-loaded longitudinal slot and substrate-integrated double line(SIDL)-excited slot-loaded patches are employed to radiate K-/Ka-band waves, respectively. Then, to constitute the 1-D K-/Ka-band arrays, the center-fed SICL feed network and SIDL-based full diferential feed network are introduced to widen the bandwidth. Finally, the GCPW-toSICL and GCPW-to-SIW transitions are adopted to excite the proposed array, respectively. Both SICL and SIDL feed networks are located below the radiating aperture. Those arrays are interleaved and shared the same radiation aperture, as well as the shielding metallic-via-array for achieving a compact footprint. To excite the above radiating elements, the SICL center feed network and fully diferential feed network are introduced to widen the bandwidth. The channel isolation is improved by utilizing the fully diferential feed network and the filtering response of the SIW. Equivalent circuits are proposed for designing the proposed antenna. Thanks to the miniaturized geometries of K-/Ka-band arrays, the proposed antenna is able to scan up to 60? and 35? at K-/Ka-band, respectively. As an example, a shared-aperture array with a steerable beam is developed and fabricated by using a multilayer printed circuited board with the designed frequencies of 19 GHz(17.7–20.2 GHz) and 29 GHz(27.5–30 GHz). The aperture dimension of the array antenna is49.6 mm×40.75 mm. A good consistency between the simulation and measurement is acquired. The measured peak gains in K-/Ka-band are 16.6 and 17.6 d Bi. When the radiation beam points to 0?, the 3-d B gain bandwidth at K-band is 14.9%(17.4–20.2 GHz), while the 3 d B gain bandwidth at Ka-band covers from 27.6to 30.4 GHz, i.e., a bandwidth of 9.7%. When the radiation beams are deflected to 60? and 35?, the measured gains of the proposed antenna flu

关键词： shared-aperture high isolation beam-scanning substrate-integrated coaxial line substrate-integrated double line

Mode analysis and structure parameter optimization of a novel SiGe-OI rib optical waveguide

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Journal of Semiconductors 2009年第8期30卷 90-94页

作者：冯松高勇杨媛冯玉春 Department of Electronic Engineering Xi'an University of Technology key laboratories of Optoelectronic Devices and Systems Shenzhen University

The mode of a novel SiGe-OI optical waveguide is analyzed, and its single-mode conditions are derived. The Ge content and structure parameters of SiGe-OI optical waveguides are respectively optimized. Under an operation wavelength of 1300 nm, the structures of SiGe-OI rib optical waveguides are built and analyzed with Optiwave software, and the optical field and transmission losses of the SiGe-OI rib optical waveguides are analyzed. The optimization results show that when the structure parameters H, h, W are respectively 500 nm, 250 nm, 500 nm and the Ge content is 5%, the total power loss of SiGe-OI rib waveguides is 0.3683 dB/cm considering the loss of radiation outside the waveguides and materials, which is less than the traditional value of 0.5 dB/cm. The analytical technique for SiGe-OI optical waveguides and structure parameters computed by this paper are proved to be accurate and computationally efficient compared with the beam propagation method （BPM） and the experimental results.

关键词： SiGe-OI rib optical waveguides mode analysis Ge content structure parameters

Wafer level hermetic packaging based on Cu-Sn isothermal solidification technology

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Journal of Semiconductors 2009年第8期30卷 164-168页

作者：曹毓涵罗乐 State key laboratories of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences

A novel wafer level bonding method based on Cu-Sn isothermal solidification technology is established. A multi-layer sealing ring and the bonding processing are designed, and the amount of solder and the bonding parameters are optimized based on both theoretical and experimental results. Verification shows that oxidation of the solder layer, voids and the scalloped-edge appearance of the Cu6Sn5 phase are successfully avoided. An average shear strength of 19.5 MPa and an excellent leak rate of around 1.9 × 10-9 atm cc/s are possible, meeting the demands of MIL-STD-883E.

关键词： wafer level package Cu-Sn isothermal solidification technology hermeticity

Experimental Evidences of Nearly Single-Crystalline Diamond Film

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Chinese Physics Letters 1996年第12期13卷 923-926页

作者： WANG Qi-min CHEN Qing-gui SHI Ri-hua DONG Rong-kang State key laboratories of Transducer Technology Shanghai Institute of MetallurgyChinese Academy of SciencesShanghai 200050

The experimental evidences of a nearly single-crystalline diamond film,which was prepared by high temperature heteroepitaxial growth method,have been shown by scanning electron microscopy,transmission electron diffrac... 详细信息

关键词： methods Crystalline crystalline