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Photonics Research 2019年第11期7卷 I0017-I0026页

作者： C.trager-Cowan A.Alasmari W.Avis J.Bruckbauer P.R.Edwards B.Hourahine S.Kraeusel G.Kusch R.Johnston G.Naresh-Kumar R.W.Martin M.Nouf-Allehiani E.Pascal L.Spasevski D.thomson S.Vespucci P.J.Parbrook M.D.Smith J.Enslin F.Mehnke M.Kneissl C.Kuhn t.wernicke S.Hagedorn A.Knauer V.Kueller S.Walde M.Weyers P.-M.Coulon P.A.Shields Y.Zhang L.Jiu Y.Gong R.M.Smith t.Wang A.Winkelmann Department of physics supauniversity of strathclydeglasgow G4 onguk tyndall national institute university college corkcork t12 r5cpireland Institute of solid state physics lechnische universitat berlin10623 berlingermany Ferdinand-braun-lnstitut leibniz-lnstitut fur hochstfrequenztechnik12489 berlingermany Department of electronic and electrical engineering centre of nanoscience&nanotechnologyuniversity of bathbath ba27ayuk Department of electronic and electrical engineering university of sheffieldsheffield s13jduk Laser components department laser zentrum hannover 5.v.30419 hannovergermany

In this paper we describe the scanning electron microscopy techniques of electron backscatter diffraction, electron channeling contrast imaging, wavelength dispersive X-ray spectroscopy, and cathodoluminescence hyperspectral imaging. We present our recent results on the use of these non-destructive techniques to obtain information on the topography, crystal misorientation, defect distributions, composition, doping, and light emission from a range of UV-emitting nitride semiconductor structures. We aim to illustrate the developing capability of each of these techniques for understanding the properties of UV-emitting nitride semiconductors, and the benefits were appropriate, in combining the techniques.

关键词： electron nitride doping

Electrical properties and microstructure formation of V/Al-based n-contacts on high Al mole fraction n-AlGaN layers

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Photonics Research 2020年第8期8卷 1381-1387页

作者： LUCA SULMONI FRANK MEHNKE ANNA MOGILAtENKO MARtIN GUttMANN tIM wernicke MICHAEL KNEISSL Institut für Festkorperphysik Technische Universitat Berlin10623 BerlinGermany Ferdinand-Braun-Institut Leibniz-Institut fur Höchstfrequenztechnik12489 BerlinGermany Institut für Physik Humboldt Universität zu Berlin12489 BerlinGermany

the electrical and structural properties of V/Al-based n-contacts on n‐AlxGa1−xN with an Al mole fraction x ranging from x=0.75 to x=0.95 are *** n-contacts are obtained up to x=0.75 with a contact resistivity of 5.7×10^−4Ω·cm^2 whereas for higher Al mole fraction the IV characteristics are *** electron microscopy reveals a thin crystalline AlN layer formed at the metal/semiconductor interface upon thermal *** analysis confirmed an Al enrichment at the *** interfacial nitride-based layer in n-contacts on n‐Al0.9Ga0.1N is partly amorphous and heavily contaminated by *** role and resulting limitations of Al in the metal stack for n-contacts on n-AlGaN with very high Al mole fraction are ***,ultraviolet C(UVC)LEDs grown on n‐Al0.87Ga0.13N and emitting at 232 nm are fabricated with an operating voltage of 7.3 V and an emission power of 120μW at 20 mA in cw operation.

关键词： AlGaN fraction properties

Electrical and optical characteristics of highly transparent MOVPE-grown AlGaN-based tunnel heterojunction LEDs emitting at 232 nm

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Photonics Research 2021年第6期9卷 1117-1123页

作者： FRANK MEHNKE CHRIStIAN KUHN MARtIN GUttMANN LUCA SULMONI VERENA MONtAG JOHANNES GLAAB tIM wernicke MICHAEL KNEISSL Institute of Solid State Physics Technische Universität Berlin10623 BerlinGermany Ferdinand-Braun-Institut Leibniz-Institut für Höchstfrequenztechnik12489 BerlinGermany Current address:School of Electrical and Computer Engineering Georgia Institute of TechnologyAtlantaGeorgia 30332USA

We present the growth and electro-optical characteristics of highly transparent AlGaN-based tunnel heterojunction light-emitting diodes(LEDs)emitting at 232 nm entirely grown by metalorganic vapor phase epitaxy(MOVPE).A GaN:Si interlayer was embedded into a highly Mg-and Si-doped Al_(0.87)Ga_(0.13)N tunnel junction to enable polarization field enhanced *** LEDs exhibit an on-wafer integrated emission power of 77μWat 5 mA,which correlates to an external quantum efficiency(EQE)of 0.29%with 45μWemitted through the bottom sapphire substrate and 32μW emitted through the transparent top *** depositing a highly reflective aluminum reflector,a maximum emission power of 1.73 mW was achieved at 100 mA under pulsed mode operation with a maximum EQE of 0.35%as collected through the bottom substrate.

关键词： heterojunction MOVPE AlGaN

Displacement talbot lithography for nanoengineering of III-nitride materials

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Microsystems & Nanoengineering 2019年第1期5卷 38-49页

作者： Pierre-Marie Coulon Benjamin Damilano Blandine Alloing Pierre Chausse Sebastian Walde Johannes Enslin Robert Armstrong Stephane Vezian Sylvia Hagedorn tim wernicke Jean Massies Jesus Zuniga‐Perez Markus Weyers Michael Kneissl Philip A.Shields Department of Electrical&Electronic Engineering University of BathBath BA27AYUK Universite Cote d’Azur CNRSCRHEArue B.Gregory06560 ValbonneFrance Ferdinand-Braun-Institut Leibniz-Institut fur HochstfrequenztechnikGustav-Kirchhoff-Str.412489 BerlinGermany technische Universität Berlin Institute of Solid State Physics10623 BerlinGermany

Nano-engineering III-nitride semiconductors offers a route to further control the optoelectronic properties,enabling novel functionalities and *** a variety of lithography techniques are currently employed to nanoengineer these materials,the scalability and cost of the fabrication process can be an obstacle for large-scale *** this paper,we report on the use of a fast,robust and flexible emerging patterning technique called Displacement talbot lithography(DtL),to successfully nano-engineer III-nitride ***,along with its novel and unique combination with a lateral planar displacement(D^(2)tL),allow the fabrication of a variety of periodic nanopatterns with a broad range of filling factors such as nanoholes,nanodots,nanorings and nanolines;all these features being achievable from one single *** illustrate the enormous possibilities opened by DtL/D2tL,dielectric and metal masks with a number of nanopatterns have been generated,allowing for the selective area growth of InGaN/GaN core-shell nanorods,the top-down plasma etching of III-nitride nanostructures,the top-down sublimation of GaN nanostructures,the hybrid top-down/bottom-up growth of AlN nanorods and GaN nanotubes,and the fabrication of nanopatterned sapphire substrates for AlN *** with their planar counterparts,these 3D nanostructures enable the reduction or filtering of structural defects and/or the enhancement of the light extraction,therefore improving the efficiency of the final *** results,achieved on a wafer scale via DtL and upscalable to larger surfaces,have the potential to unlock the manufacturing of nano-engineered III-nitride materials.

关键词： talbot planar nitride

下地壳在大陆岩石圈拉伸中的作用——BIRPS深地震资料的运动学分析

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海洋地质译丛 1991年第3期 5-11页

作者： t.J.Reston 朱平

前言一般认为许多沉积盆地的形成,至少部分上是由于大陆岩石圈的扩张引起的。但岩石圈的扩张方式却不大明确,Mckenzie(1978)发展了一种模拟伸展岩石圈热演化的数学模型,成功地解释了许多盆地的沉降性状,但他没有考虑到不同岩石圈层的扩... 详细信息

前言一般认为许多沉积盆地的形成,至少部分上是由于大陆岩石圈的扩张引起的。但岩石圈的扩张方式却不大明确,Mckenzie(1978)发展了一种模拟伸展岩石圈热演化的数学模型,成功地解释了许多盆地的沉降性状,但他没有考虑到不同岩石圈层的扩张机制。相反,对大型扩张析离在美国西部所起的作用留下深刻印象的wernicke(1981,1985)。

关键词：岩石圈地壳拉伸地震

伴妊娠剧吐及酮症酸中毒的wernicke脑病

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世界核心医学期刊文摘（妇产科学分册） 2006年第10期2卷 58-59页

作者： Selitsky t. Chandra P. Schiavello H.J. 柳蕴 Department of Obstetrics and Gynecology Wyckoff Heights Medical Center 374 Stockholm Street Brooklyn NY 11237 United States Dr.

BACKGROUND: Avitaminosis can result from the acute malnutrition associated with prolonged pregnancy-related hyperemesis. Serious complications may arise from thiamine deficiency under these circumstances. CASE: We review the relevant literature and describe a case with central nervous system involvement presenting with typical manifestations of wernicke’s encephalopathy, apparently precipitated by a combination of hyperemesis gravidarum, diabetic ketoacidosis, and intravenous glucose administration. CONCLUSION: While this life-threatening complication is rare, it is important for all who care for obstetric patients to be aware of it and alert to its development. Early recognition is critical given the need to treat affected women expeditiously to help avoid potentially fatal adverse consequences. Prophylactic thiamine supplementation should be considered in the care of gravidas with hyperemesis.

关键词： wernicke 妊娠剧吐酮症酸中毒脑病静脉葡萄糖中枢神经系统

1例wernicke脑病患者从上视性到下视性眼球震颤的转变

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世界核心医学期刊文摘（眼科学分册） 2005年第10期1卷 52-52页

作者： Suzuki Y. Matsuda t. Washio N. Ohtsuka K. 潘佳鸿 Department of Ophthalmol ogy Sapporo Medical University School of Medicine S1W16 Chuo-ku Sapporo 06 0-8543 Japan

Background: We report an unusual case of wernicke’s encephalopathy presenting with transient upbeat nystagmus that changed to a persistent downbeat nystagmus . Case: A 27-year-old man presented with upbeat nystagmus. three months earlie r, he had been diagnosed with wernicke’s encephalopathy after fasting for a mon th. Observations: this diagnosis was supported by his symptoms (ataxia, a confus ed state). Clinical recovery followed thiamine therapy. His upbeat nystagmus had linear slow phases with average amplitude and frequency (±SD) during fixation straight ahead of 2.8±0.7°and 4.6±2.2Hz. respectively. two months later, the primary position upbeat nystagmus had diminished and down beat nystagmus (0.9 + 0.5°and 3.2±0.7 Hz on average) for a 20°downward gaze had developed. then, 8 months later, he showed only downbeat nystagmus, which obeyed Alexander’s law. His primary position downbeat nystagmus was completely suppressed by clonazepam, a γ-aminobutyric acid (GABA) agonist. Conclusions: Owing to an underlying cen tral vestibular imbalance, even after the recovery of acute neurological symptom s, wernicke’s encephalopathy can be complicated by persistent downbeat nystagmu s, which can be treated by a GABA agonist.

关键词： wernicke 下视性眼球震颤脑病患者上视共济失调前庭功能眼位激动剂临床康复氯硝西泮