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Al-free cladding-layer blue laser diodes with a low aspect ratio in far-field beam pattern

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Journal of Semiconductors 2018年第8期39卷 57-61页

作者： Meixin Feng Qian Sun Jianping liu zengcheng li Yu Zhou Hongwei Gao Shuming Zhang Hui Yang Key Laboratory of Nano-Devices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO) Chinese Academy of Sciences School of Nano Technology and Nano Bionics University of Science and Technology of China

c-plane GaN-based blue laser diodes（LDs） were fabricated with Al-free cladding layers（CLs） and deepened etching depth of mesa structure, so the aspect ratio of the far-field pattern（FFP） of the laser beam can be reduced to as low as 1.7, which is nearly the same as conventional AlGa In P-based red LDs. By using GaN CLs,the radiation angle of the laser beam θ⊥ is only 10.1° in the direction perpendicular to the junction plane. After forming a deeply etched mesa, the beam divergence angle parallel to the junction plane of FFP, θ;, increases from4.9° to 5.8°. After using the modified structure, the operation voltage of LD is effectively reduced by 2 V at an injection current of 50 mA, but the threshold current value increases. The etching damage may be one of the main reasons responsible for the increase of the threshold current.

关键词： Al-free cladding layers far-field beam patterns aspect ratio laser diodes

Characteristics of InGaN-based superluminescent diodes with one-sided oblique cavity facet

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Chinese Science Bulletin 2014年第16期59卷 1903-1906页

作者： Chang Zeng Shuming Zhang Jianping liu Deyao li Desheng Jiang Meixin Feng zengcheng li Kun Zhou Feng Wang Huaibing Wang Hui Wang Hui Yang Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of Sciences State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences

We have fabricated InGaN-based superluminescent diodes(SLDs)with one-sided oblique *** characteristics of the SLDs and laser diodes with the same cavity length(800 lm)were *** typical peak wavelength and the full width at half maximum of the spectrum in superluminescence regime are 445.3 and 7.7 nm for the SLDs with 800 lm cavity *** characteristics of the SLDs with different cavity length were also demonstrated in a comparative *** is found that the gain of the InGaN multi-quantum wells in blue spectral range is a linear function of the current density below gain saturation *** lasing threshold current turns out to be higher for the shorter SLD(S-SLD)(400 lm),but the output light intensity of the longer SLD(800 lm)is higher than that of the S-SLD under the same current *** gain saturation phenomenon was observed in S-SLD when it was biased at a current density larger than 27.5 kA/*** increase of junction temperature was identified as the main reason for gain saturation through spectra analysis.

关键词： InGaN 辐射发光半导体激光增益饱和特征腔面管片电流密度

Room-temperature continuous-wave electrically pumped InGaN/GaN quantum well blue laser diode directly grown on Si

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light(Science & Applications) 2018年第1期7卷 904-910页

作者： Yi Sun Kun Zhou Meixin Feng zengcheng li Yu Zhou Qian Sun Jianping liu liqun Zhang Deyao li Xiaojuan Sun Dabing li Shuming Zhang Masao Ikeda Hui Yang Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)Suzhou 215123China School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei 230026China Accelink Technologies Co. LtdWuhan 430205China State Key Laboratory of Luminescence and Applications Changchun Institute of Optics Fine Mechanics and Physics(CIOMP)CASChangchun 130033China

Current laser-based display and lighting applications are invariably using blue laser diodes(LDs)grown on freestanding GaN substrates,which are costly and smaller in size compared with other substrate materials.1–3 Utilizing less expensive and large-diameter Si substrates for hetero-epitaxial growth of indium gallium nitride/gallium nitride(InGaN/GaN)multiple quantum well(MQW)structure can substantially reduce the cost of blue LDs and boost their *** obtain a high crystalline quality crack-free GaN thin film on Si for the subsequent growth of a blue laser structure,a hand-shaking structure was formed by inserting Al-composition step down-graded AlN/AlxGa1−xN buffer layers between GaN and Si *** degradation in InGaN/GaN blue MQWs was successfully suppressed with indium-rich clusters eliminated by introducing hydrogen during the growth of GaN quantum barriers(QBs)and lowering the growth temperature for the p-type AlGaN/GaN superlattice optical cladding layer.A continuous-wave(CW)electrically pumped InGaN/GaN quantum well(QW)blue(450 nm)LD grown on Si was successfully demonstrated at room temperature(RT)with a threshold current density of 7.8 kA/cm^(2).

关键词： pumped quantum wave

light output improvement of GaN-based light-emitting diodes grown on Si (111) by a via-thin-film structure

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Journal of Semiconductors 2018年第4期39卷 39-43页

作者： zengcheng li Bo Feng Biao Deng Legong liu Yingnan Huang Meixin Feng Yu Zhou Hanmin Zhao Qian Sun Huaibing Wang Xiaoli Yang Hui Yang Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Suzhou 215123 China Lattice Power (Changzhou) Corporation Changzhou 213164 China Lattice Power (Jiangxi) Corporation Nanchang 330029 China Beijing Advanced Materials Development Center Beijing 100083 China

This work reports the fabrication of via-thin-film light-emitting diode （via-TF-LED） to improve the light output power （LOP） of blue/white GaN-based LEDs grown on Si （111） substrates. The as-fabricated via-TF-LEDs were featured with a roughened n-GaN surface and the p-GaN surface bonded to a wafer carrier with a silver-based reflective electrode, together with an array of embedded n-type via pillar metal contact from the p-GaN surface etched through the multiple-quantum-wells （MQWs） into the n-GaN layer. When operated at 350 mA, the via-TF- LED gave an enhanced blue LOP by 7.8% and over 3.5 times as compared to the vertical thin-film LED （TF-LED） and the conventional lateral structure LED （LS-LED）. After covering with yellow phosphor that converts some blue photons into yellow light, the via-TF-LED emitted an enhanced white luminous flux by 13.5% and over 5 times, as compared with the white TF-LED and the white LS-LED, respectively. The significant LOP improve- ment of the via-TF-LED was attributed to the elimination of light absorption by the Si （111） epitaxial substrate and the finger-like n-electrodes on the roughened emitting surface.

关键词： via thin film LED structure GaN-on-Si light-emitting diode light extraction

尿蛋白、白蛋白和胆固醇检测在肾病综合征诊断中的意义

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实用医技杂志 2004年第6A期11卷 865-866页

作者：林荔增城市中医院广东增城511300

目的 :检测 2 4 h尿蛋白、血浆白蛋白 (Alb)、胆固醇 (Cho)对肾病综合征 (NS)的临床应用价值。方法 :检测肾病综合征患者 5 2例 ,急、慢性肾小球肾炎患者 2 9例和健康体检者 30例蛋白尿、血浆白蛋白和胆固醇的活性水平。结果 :肾病综合... 详细信息

目的 :检测 2 4 h尿蛋白、血浆白蛋白 (Alb)、胆固醇 (Cho)对肾病综合征 (NS)的临床应用价值。方法 :检测肾病综合征患者 5 2例 ,急、慢性肾小球肾炎患者 2 9例和健康体检者 30例蛋白尿、血浆白蛋白和胆固醇的活性水平。结果 :肾病综合征患者尿蛋白、血浆白蛋白和胆固醇含量分别为 (5 .1± 1.5 ) g/ d,(18.7± 10 .4 ) g/ L和 (12 .2 3± 2 .6 5 ) mm ol/ L,明显高于急、慢性肾炎和健康对照 ,差异有显著性 (P<0 .0 0 1)。结论 :疑为肾病综合征时检测尿蛋白、血浆白蛋白 (Alb)和胆固醇 (Cho)

关键词：尿蛋白白蛋白胆固醇肾病综合征肾脏病

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提高思想政治理论课教学效果的探索

天津电大学报 2006年第4期10卷 21-23页

作者：周明李增城楚莉莉天津广播电视大学天津300191

从2006年秋季新生入学开始,在全国高校统一实施思想政治理论课的新课程方案。思想政治理论课教学要针对课程的新要求、新特点进行实践和探索,贴近实际,贴近学生,不断提高思想政治理论课的教学效果。

关键词：思政课贴近实际贴近学生认知规律

Reversible li plating regulation on graphite anode through a barium sulfate nanofibers-based dielectric separator for fast charging and high-safety lithium-ion battery

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Journal of Energy Chemistry 2025年第2期101卷 511-523页

作者： Yaxin Zhang Long Cheng Ying-Jie Zhu Jin Wu Han-Ping Yu Sida Xie Dandan li Zhaohui Wang Heng li State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences College of Materials Science and Engineering Hunan University Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Poor li plating reversibility and high thermal runaway risks are key challenges for fast charging lithiumion batteries with graphite ***,a dielectric and fire-resistant separator based on hybrid nanofibers of barium sulfate（BS） and bacterial cellulose（BC） is developed to synchronously enhance the battery's fast charging and thermal-safety *** regulation mechanism of the dielectric BS/BC separator in enhancing the li+ion transport and li plating reversibility is revealed.（1） The Max-Wagner polarization electric field of the dielectric BS/BC separator can accelerate the desolvation of solvated li+ions,enhancing their transport kinetics.（2） Moreover,due to the charge balancing effect,the dielectric BS/BC separator homogenizes the electric field/li+ion flux at the graphite anode-separator interface,facilitating uniform li plating and suppressing li dendrite ***,the fast-charge graphite anode with the BS/BC separator shows higher Coulombic efficiency（99.0% vs.96.9%） and longer cycling lifespan（100 cycles vs.59 cycles） than that with the polypropylene（PP） separator in the constantlithiation cycling test at 2 mA *** high-loading liFePO4(15.5 mg cm-2)//graphite(7.5 mg cm-2) full cell with the BS/BC separator exhibits excellent fast charging performance,retaining 70% of its capacity after 500 cycles at a high rate of 2C,which is significantly better than that of the cell with the PP separator（retaining only 27% of its capacity after 500 cycles）.More importantly,the thermally stable BS/BC separator effectively elevates the critical temperature and reduces the heat release rate during thermal runaway,thereby significantly enhancing the battery's safety.

关键词： Fast charging Graphite anode Ion transport lithium-ion battery Separator

Significant reduction of anisotropy in stress relaxation aging and mechanical properties improvement for 2195 Al-Cu-li alloy subjected to plastic loading

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Chinese Journal of Aeronautics 2025年第1期38卷 217-234页

作者： liwen ZHANG Heng li Tianjun BIAN Changhui WU Yanfeng YANG State Key Lab of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Xi’an Aeronautical Polytechnic Institute Xi’an 710089China Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Although the plastic loading can enhance creep deformation and yield strength,the anisotropic Stress Relaxation Aging(SRA)behavior and mechanism under plastic loading remain unclear,which presents a significant challenge in accurately shaping aluminum alloy *** this study,the SRA behavior of 2195-T4 Al-Cu-li alloys were thoroughly studied under initial loading stresses within the elastic(210/250 MPa)and plastic(380/420 MPa)ranges at 180℃by stress relaxation and tensile tests as well as microstructure *** findings reveal that compared with those under elastic loadings,in-plane anisotropy(IPA)values of the stress relaxation amount,yield strength and fracture elongation under plastic loadings are reduced by 60%–80%,70%–90% and 72%–89%,***,IPA values of precipitate size in grains and PrecipitationFree Zones(PFZ)width at grain boundaries under plastic loading decrease by 31.4%and 94.4%*** results indicate plastic loading significantly weakens the anisotropic SRA behavior,owing to numerous uniformly distributed fine T1phases and small IPA values of both T1precipitates size and PFZ width in various loading *** with those of elastic loadingaged alloys,yield strength of plastic loading-aged alloys shows high strength-ductility because of the combined effect of closely dispersed fine T1precipitates,narrowed PFZ and numerous sheared and rotated T1phases at different locations during tensile *** uniformly distributed larger Kernel Average Misorientation(KAM)and Schmidt factor values of the plastic loading-aged alloy,as well as the cross-slip generated,also help to enhance the strength and ductility of the alloy.

关键词： Aluminum-lithium alloy Stress relaxation aging Precipitation-free zones In-plane anisotropy Stress relaxation

A Review on Thermal Management of li-ion Battery:from Small-Scale Battery Module to Large-Scale Electrochemical Energy Storage Power Station

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Journal of Thermal Science 2025年第1期34卷 1-23页

作者： CHEN Zhifeng JIA li YIN liaofei DANG Chao REN Honglei ZHANG Zhiqiang Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

li-ion battery is an essential component and energy storage unit for the evolution of electric vehicles and energy storage technology in the ***,in order to cope with the temperature sensitivity of li-ion battery and maintain li-ion battery safe operation,it is of great necessary to adopt an appropriate battery thermal management system(BTMS).In this paper,the current main BTM strategies and research hotspots were discussed from two aspects:small-scale battery module and large-scale electrochemical energy storage power station(EESPS).The practical application situation,advantages and disadvantages,and the future development trend of each heat dissipation method(air,liquid,PCM,heat pipe,hybrid cooling)were described in *** them,the air cooling and liquid cooling were reviewed in-depth based on the engineering *** PCM,heat pipe and hybrid cooling were reviewed extensively based on the latest *** research provides a comprehensive understanding for the BTMS in all scales.

关键词： battery thermal management cooling methods small-scale battery module large-scale electrochemical energy storage power station