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Improving the incorporation of indium component for InGaN-based green LED through inserting photonic crystalline in the GaN layer

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Journal of Semiconductors 2022年第7期43卷 84-88页

作者： Yunqi Li Xinwei Wang Ning Zhang xuecheng wei Junxi Wang Institute of First Medical Center Chinese PLA General HospitalBeijing 100853China State Key Laboratory of Solid-State Lighting Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

We report on the effect of inserted photonic crystalline(Ph-C) in the GaN epitaxial layer on the incorporation of the indium component for the InGaN-based green LED. The adoption of Ph-C in the GaN layer shifted the Raman peak value of E2mode of GaN to lower frequency and resulted in a tensive stress relief. The stress relief can be attributed to strained lattices restoring in the matrix of Ph-C and the GaN pseudo-epitaxy over the air-void of the Ph-C. Moreover, the HRXRD rocking curves and AFM results show that the insertion of Ph-C also improves the crystal quality. With the inserted Ph-C, the indium component in the multiple quantum wells of the green LED(Ph-C LED) was enhanced. This resulted in a 6-nm red-shift of the peak wavelength. Furthermore, the LOP of the Ph-C LED was enhanced by 10.65% under an injection current of 20 mA.

关键词： epitaxial growth nanocrystalline materials semiconductors Raman stress relief X-ray techniques

Deep ultraviolet light-emitting diodes based on a well-ordered AlGaN nanorod array

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Photonics Research 2019年第9期7卷 941-947页

作者： LIANG ZHANG YANAN GUO JIANCHANG YAN QINGQING WU YI LU ZHUOHUI WU WEN GU xuecheng wei JUNXI WANG JINMIN LI Research and Development Center for Solid State Lighting Institute of SemiconductorsChinese Academy of SciencesBeijing100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Beijing Engineering Research Center for the3rd Generation Semiconductor Materials and Application Beijing100083China State Key Laboratory of Solid-State Lighting Beijing100083China

The nanorod structure is an alternative scheme to develop high-efficiency deep ultraviolet light-emitting diodes(DUV LEDs). In this paper, we first report the electrically injected 274-nm AlGaN nanorod array DUV LEDs fabricated by the nanosphere lithography and dry-etching technique. Nanorod DUV LED devices with good electrical properties are successfully realized. Compared to planar DUV LEDs, nanorod DUV LEDs present>2.5 times improvement in light output power and external quantum efficiency. The internal quantum efficiency of nanorod LEDs increases by 1.2 times due to the transformation of carriers from the exciton to the free electron–hole, possibly driven by the interface state effect of the nanorod sidewall surface. In addition, the nanorod array significantly facilitates photons escaping from the interior of LEDs along the vertical direction, contributing to improved light extraction efficiency. A three-dimensional finite-different time-domain simulation is performed to analyze further in detail the TE-and TM-polarized photon extraction mechanisms of the nanostructure. Our results demonstrate the nanorod structure is a good candidate for high-efficiency DUV emitters.

关键词： Deep ultraviolet light-emitting diodes based on a well-ordered AlGaN nanorod array AlGaN

Balancing charge injection in quantum dot light-emitting diodes to achieve high efficienciy of over 21%

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Science China Materials 2022年第7期65卷 1882-1889页

作者： Chunyan Cheng Xuejiao Sun Zhiwei Yao Chenghao Bi xuecheng wei Junxi Wang Jianjun Tian Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China

Quantum dot light-emitting diodes(QLEDs)have attracted considerable attention in displays owing to their high color purity,wide gamut,narrow emission band,and solution-processed ***,a major problem of the unbalanced carrier(electrons and holes)injection in QLEDs deteriorates their ***,we balanced the charge injection in QLEDs by optimizing the carrier transport *** organic hole transport layers(HTLs)with a suitable thickness were employed to match the electron transport layer(ETL)of ***^(2+) was doped into the ZnO(MZO)ETL to decrease the electron mobility and match the hole mobility of the ***,the QLEDs exhibited an excellent external quantum efficiency(EQE)of 21.10%at a luminance of 4661 cd m^(-2).In the luminance range of 100–30,000 cd m^(-2),EQE roll-off was considerably low,and more than 80%of the initial EQE value could be maintained,indicating less Auger recombination because of the balanced carrier *** work reveals that compared with energy level matching,the charge transfer capability of the transport layers is more instrumental in the charge balance regulation of QLED devices.

关键词： quantum dot light-emitting diode charge balance high efficiency

Study of the morphology evolution of AlN grown on nanopatterned sapphire substrate

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Journal of Semiconductors 2019年第12期40卷 130-134页

作者： Zhuohui Wu Jianchang Yan Yanan Guo Liang Zhang Yi Lu xuecheng wei Junxi Wang Jinmin Li Research and Development Center for Solid State Lighting Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Engineering Research Center for the 3rd Generation Semiconductor Materials and Application Beijing 100083China State Key Laboratory of Solid-State Lighting Beijing 100083China

This study focused on the evolution of growth front about AlN growth on nano-patterned sapphire substrate by metal-organic chemical vapor *** substrate with concave cones was fabricated by nano-imprint lithography and wet *** samples with different epitaxy procedures were fabricated,manifesting as two-dimensional growth mode and three-dimensional growth mode,*** results showed that growth temperature deeply influenced the growth modes and thus played a critical role in the coalescence of *** a relatively high temperature,the AlN epilayer was progressively coalescence and the growth mode was *** this case,we found that the inclined semi-polar facets arising in the process of coalescence were{112^-1}*** when decreasing the temperature,the{112^-2}semi-polar facets arose,leading to inverse pyramid morphology and obtaining the three-dimensional growth *** 3 D inverse pyramid AlN structure could be used for realizing 3 D semi-polar UV-LED or facet-controlled epitaxial lateral overgrowth of AlN.

关键词： AlN epitaxial lateral overgrowth growth front evolution 2D and 3D growth modes MOCVD

NH_(3)/N_(2)复合热退火技术改善高浓度Mg掺杂GaN材料性能

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发光学报 2024年第8期45卷 1325-1333页

作者：蒋宗霖闫丹张宁魏同波王军喜魏学成中国科学院半导体研究所宽禁带半导体研发中心北京100083 中国科学院大学材料科学与光电技术学院北京100049

研究了NH_(3)/N_(2)复合热退火技术对高浓度Mg掺杂GaN材料晶体质量、发光性质及导电性能的影响。实验结果表明,相较于传统N_(2)氛围高温热退火后处理工艺而言,NH_(3)氛围高温热退火后处理工艺可以改善高浓度Mg掺杂GaN材料的晶体质量,同... 详细信息

研究了NH_(3)/N_(2)复合热退火技术对高浓度Mg掺杂GaN材料晶体质量、发光性质及导电性能的影响。实验结果表明,相较于传统N_(2)氛围高温热退火后处理工艺而言,NH_(3)氛围高温热退火后处理工艺可以改善高浓度Mg掺杂GaN材料的晶体质量,同时可以增进Mg受主原子的有效掺杂,使得其光致发光谱中蓝光峰强度增强。采用NH_(3)氛围高温热退火结合N_(2)氛围低温热退火后处理工艺复合技术制备得到的高浓度Mg掺杂GaN材料内部背景电子浓度显著降低。这是由于在NH_(3)氛围高温热退火后处理工艺中,NH_(3)的热分解产物能够有效降低材料内N空位和间隙Ga原子等浅施主型缺陷浓度,最终改善高浓度Mg掺杂GaN材料的导电性能。

关键词：氮化镓 Mg掺杂热退火工艺氨气

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3-27 Characteristics of Luminescence of N Ion Irradiated LED

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IMP & HIRFL Annual Report 2014年第1期 121-122页

作者： Gou Jie Zhang Chonghong Song Yin Yang Yitao Yi Xiaoyan wei xuecheng Xie Haizhong Liu Juan Xian Yongqiang Zhang Liqing 不详

In the present work, the LED chip was irradiated by using 59.6 MeV N ions in a terminal chamber of theSector-focused cyclotron (SFC) in the National Labortary of Heavy-ion Accelerators in Lanzhou. The 63 MeV Nions penetrated through a gold foil and scattered in a large area. The energy of ion was reduced to 59.6 MeV afterscattering of the gold foil. The LED was provided by the Semiconductor Lighting Center in Institute of Semiconductorin Beijing. The luminences of the LED before/after irradiation were tested through a integrating sphere inSemiconductor Lighting Center in Institute of Semiconductor in Beijing. The luminance was tested under a currentof 350 mA. Fig. 1 shows the relationship between the luminences and the irradiation fluences. The irradiation led

关键词： Characteristics Luminescence Irradiated

Sequence Analysis of Arthrospira maxima Based on Fosmid Library

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Sequence Analysis of Arthrospira maxima Based on Fosmid Libr...

拉萨拉鲁湿地生态学特征及恢复与重建措施研究

中国海洋湖沼学会藻类学分会第七届会员大会暨第十四次学术讨论会

作者： Na Ling Yunxiang Mao~* xuecheng Zhang wei Liu(College of Marine Life Science,Ocean University of China 266003,China)

Arthrospira(Spirulina)(Setchell&Gardner)is an important cyanobacterium not only in its nutritional potential but in its special biological *** unbiased fosmid library of Arthrospira maxima FACHB438 that contains 4300 clones was *** size distribution of insert fragments is from 15.5 to 48.9 kb and the average size is 37.6 *** recombination frequency is 100%.Therefore the library is 29.9 equivalents to the Arthrospira genome size of 5.4 Mb.A total of 719 sample clones were randomly chosen from the library and 602 available sequences, which consisted of 307,547 bases,covering 5.70% of the whole *** codon usage of *** was not strongly *** content at the first position of codons(46.9%)was higher than the second(39.8%)and the third(45.5%)positions. GC content of the genome was 43.6%.Of these sequences,287(47.7%)showed high similarities to known genes,63(10.5%)to hypothetical genes and the remaining 252 (41.8%)had no significant *** assigned genes were classified into 22 categories with respect to different biological ***,the high presence of 25 sequences(4.2%)encoding reverse transcriptase indicates the RT gene may have multiple copies in the *** genome and might play an important role in the evolutionary history and metabolic *** addition,the sequences encoding the ATP-binding cassette transport system and the two-component signal transduction system were the second and third most frequent genes,*** genomic features provide some clues as to the mechanisms by which this organism adapts to the high concentration of bicarbonate and to the high pH environment.

关键词： ABC transporter system Arthrospira maxima Codon usage Functional classification Reverse transcriptase TCSTsystem

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西藏科技 2002年第4期 58-63页

作者：卫学承西藏自治区畜牧研究所

拉萨“拉鲁湿地”草场植被由沼泽和草甸组成 ,两者合计占湿地总面积85%以上 ;其次是荒漠和灌丛 ,占 1 5%。沼泽植被以水生芦苇为健群种 ,伴生苔草、香蒲、三角草等。实测亩产鲜草达 2 1 0 8 8千克± 791 3,土壤PH6 3— 6 8;草甸植被... 详细信息

拉萨“拉鲁湿地”草场植被由沼泽和草甸组成 ,两者合计占湿地总面积85%以上 ;其次是荒漠和灌丛 ,占 1 5%。沼泽植被以水生芦苇为健群种 ,伴生苔草、香蒲、三角草等。实测亩产鲜草达 2 1 0 8 8千克± 791 3,土壤PH6 3— 6 8;草甸植被由沼泽退化而来 ,植被以小嵩草、藏嵩草等为健群种 ,亩产鲜草 70 1 7千克± 34 4,土壤PH6 9-7 1拉鲁湿地物种多样性表现 :植物十八种、兽类 7种、鸟类 1 4种 (含国家Ⅰ级保护鸟二种 )、鱼类 5种。原始自然景观良好 ,是物种多样性保存完正的原始基因库。九十年代后因多种原因 ,湿地破坏严重、面积缩小 ,植被种类和产量锐减 ,鸟类兽类灭绝、鼠害严重 ,草场退化、土壤盐渍化。为此 ,本文介绍了拉鲁湿地的生态学特征 ,并从政策措施 ,生物措施和工程措施这三个方面提出了对拉鲁湿地生态系统恢复和重建的具体措施 ,可供参考。

关键词：拉萨拉鲁湿地生态学特征生态恢复生态重建

AC Plasma-enhanced Chemical Vapor Deposition of Carbon Nitride Thin Films

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AC Plasma-enhanced Chemical Vapor Deposition of Carbon Nitri...