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| 1 | Improved performance of UVC-LEDs by combination of high-temperature annealing and epitaxially laterally overgrown AlN/sapphire显示文摘We report on the performance of AlGaN-based deep ultraviolet light-emitting diodes(UV-LEDs)emitting at 265 nm grown on stripe-patterned high-temperature annealed(HTA)epitaxially laterally overgrown(ELO)aluminium nitride(AIN)/sapphire templates.For this purpose,the structural and electro-optical properties of ultraviolet-c light-emitting diodes(UVC-LEDs)on as-grown and on HTA planar AlN/sapphire as well as ELO AlN/sapphire with and without HTA are investigated and compared.Cathodoluminescence measurements reveal dark spot densities of 3.5×10^9 cm^-2,1.1×10^9 cm^-2,1.4×10^9 cm^-2,and 0.9×10^9 cm^-2 in multiple quantum well samples on as-grown planar AIN/sapphire,HTA planar AlN/sapphire,ELO AlN/sapphire,and HTA ELO AlN/sapphire,respectively,and are consistent with the threading dislocation densities determined by transmission electron microscopy(TEM)and high-resolution X-ray diffraction rocking curve.The UVC-LED performance improves with the reduction of the threading dislocation densities(TDDs).The output powers(measured on-wafer in cw operation at 20 mA)of the UV-LEDs emitting at 265 nm were 0.03 mW(planar AlN/sapphire),0.8 mW(planar HTA AlN/sapphire),0.9 mW(ELO AlN/sapphire),and 1.1 mW(HTA ELO AlN/sapphire),respectively.Furthermore,Monte Carlo ray-tracing simulations showed a 15%increase in light-extraction efficiency due to the voids formed in the ELO process.These results demonstrate that HTA ELO AlN/sapphire templates provide a viable approach to increase the efficiency of UV-LEDs,improving both the internal quantum efficiency and the light-extraction efficiency. | NORMAN SUSILO EVIATHAR ZIFFER SYLVIA HAGEDORN LEONARDO CANCELLARA CARSTEN NETZEL NEYSHA LOBO PLOCH SHAOJUN WU JENS RASS SEBASTIAN WALDE LUCA SULMONI MARTIN GUTTMANN TIM WERNICKE MARTIN ALBRECHT MARKUS WEYERS MICHAEL KNEISSL | 2020 | Photonics Research2020，8，4： | 4 |
| 2 | Electrical properties and microstructure formation of V/Al-based n-contacts on high Al mole fraction n-AlGaN layers显示文摘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 investigated.Ohmic 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 rectifying.Transmission electron microscopy reveals a thin crystalline AlN layer formed at the metal/semiconductor interface upon thermal annealing.Compositional analysis confirmed an Al enrichment at the interface.The interfacial nitride-based layer in n-contacts on n‐Al0.9Ga0.1N is partly amorphous and heavily contaminated by oxygen.The role and resulting limitations of Al in the metal stack for n-contacts on n-AlGaN with very high Al mole fraction are discussed.Finally,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. | LUCA SULMONI FRANK MEHNKE ANNA MOGILATENKO MARTIN GUTTMANN TIM WERNICKE MICHAEL KNEISSL | 2020 | Photonics Research2020，8，8： | 4 |
| 3 | Spatialities of ageing: The co-construction and co-evolution of old age and space显示文摘 | Tim Schwanen Irene Hardill Susan Lucas | 2012 | Geoforum2012，，6： | 2 |
| 4 | Heritability esti- mates for growth in the tropical abalone Haliotis asinina us- ing microsatellites to assign parentage 显示文摘 | Tim Lucas Michael M Sandie M D | 2006 | Aquaculture2006，259，： | 1 |
| 5 | Heritability estimates for growth in the tropical abalone Haliotis asinina using microsatellites to assign parentage显示文摘 | Tim Lucas Michael Macbeth Sandie M. Degnan Wayne Knibb Bernard M. Degnan | 2006 | Aquaculture2006，，1： | 1 |
| 6 | Tribological behavior of HVOF- and HVAF-sprayed composite coatings based on Fe-Alloy+WC–12% Co显示文摘 | Giovanni Bolelli Tim B?rner Andrea Milanti Luca Lusvarghi Jussi Laurila Heli Koivuluoto Kari Niemi Petri Vuoristo | 2014 | Surface & Coatings Technology2014，，： | 1 |
| 7 | Heritability estimates for growth in the tropical abalone Haliotis asinina using microsatellites to assign parentage显示文摘 | Tim Lucas Michael Macbeth Sandie M. Degnan Wayne Knibb Bernard M. Degnan | 2006 | Aquaculture2006，，1： | 1 |
| 8 | Subtalar versus triple arthrodesis after intra-articular calcaneal fractures显示文摘 | Tim Schepers Brenda C. T. Kieboom Gert H. J. M. Bessems Lucas M. M. Vogels Esther M. M. Lieshout Peter Patka | 2010 | Strategies in Trauma and Limb Reconstruction2010，，2： | 1 |
| 9 | Spatialities of ageing: The co-construction and co-evolution of old age and space显示文摘 | Tim Schwanen Irene Hardill Susan Lucas | 2012 | Geoforum2012，，6： | 1 |
| 10 | The management of acute distal tibio-fibular syndesmotic injuries: Results of a nationwide survey显示文摘 | Tim Schepers Wouter J. van Zuuren Michel P.J. van den Bekerom Lucas M.M. Vogels Esther M.M. van Lieshout | 2012 | Injury2012，，10： | 1 |
| 11 | Promotion of Faster Weight Gain in Infants Born Small for Gestational Age: Is There an Adverse Effect on Later Blood Pressure?显示文摘 | Atul Singhal Tim J. Cole Mary Fewtrell Kathy Kennedy Terence Stephenson Alun Elias-Jones Alan Lucas | 2007 | Circulation2007，，2： | 1 |
| 12 | Extended Lateral Approach for Intra-articular Calcaneal Fractures: An Inverse Relationship between Surgeon Experience and Wound Complications显示文摘 | Tim Schepers Dennis Den Hartog Lucas M.M. Vogels Esther M.M. Van Lieshout | 2013 | The Journal of Foot and Ankle Surgery2013，，： | 1 |
| 13 | MOVPE-grown AlGaN-based tunnel heterojunctions enabling fully transparent UVC LEDs显示文摘We report on AlGaN-based tunnel heterojunctions grown by metalorganic vapor phase epitaxy enabling fully transparent UVC LEDs by eliminating the absorbing p-AlGaN and p-GaN layers. Furthermore, the electrical characteristics can be improved by exploiting the higher conductivity of n-AlGaN layers as well as a lower resistance of n-contacts. UVC LEDs with AlGaN:Mg/AlGaN:Si tunnel junctions exhibiting single peak emission at268 nm have been realized, demonstrating effective carrier injection into the AlGaN multiple quantum well active region. The incorporation of a low band gap interlayer enables effective tunneling and strong voltage reduction.Therefore, the interlayer thickness is systematically varied. Tunnel heterojunction LEDs with an 8 nm thick GaN interlayer exhibit continuous-wave emission powers >3 m W near thermal rollover. External quantum efficiencies of 1.4% at a DC current of 5 m A and operating voltages of 20 V are measured on-wafer. Laterally homogeneous emission is demonstrated by UV-sensitive electroluminescence microscopy images. The complete UVC LED heterostructure is grown in a single epitaxy process including in situ activation of the magnesium acceptors. | Christian Kuhn Luca Sulmoni Martin Guttmann Johannes Glaab Norman Susilo Tim Wernicke Markus Weyers Michael Kneissl | 2019 | Photonics Research2019，7，5： | 1 |
| 14 | Potential importance of early treatment of SARS-CoV-2 infection in intestinal transplant patient: A case report显示文摘BACKGROUND Predispositions for severe coronavirus disease 2019(COVID-19)are age,immunosuppression,and co-morbidity.High levels of maintenance immunosuppression render intestinal transplant(ITx)patients vulnerable for severe COVID-19.COVID-19 also provokes several gastroenterological pathologies which have not been discussed in ITx,so far.CASE SUMMARY During the second European COVID-19 wave in November 2020,an ITx recipient was admitted to the hospital because of electrolyte disturbances due to dehydration.Immunosuppression consisted of tacrolimus,azathioprine,and low-dose corticosteroids.During hospitalization,she tested positive on screening COVID-19 nasopharyngeal polymerase chain reaction swab,while her initial test was negative.She was initially asymptomatic and had normal inflammatory markers.Tacrolimus levels were slightly raised,as Azathioprine was temporarily halted.Due to elevated Ddimers at that time,prophylactic low-molecular weight heparin was started.Seven days after the positive test,dyspnea,anosmia,and C-reactive protein increase(25 mg/L)were noted.Remdesivir was administered during 5 d in total.High stomal output was noted in two consecutive days and several days thereafter.To exclude infection or rejection,an ileoscopy and biopsy were performed and excluded these.Four weeks later,she was discharged from the hospital and remains in good health since then.CONCLUSION Early eradication of severe acute respiratory syndrome coronavirus 2 in ITx recipients may be warranted to prevent acute rejection provocation by it. | Mathias Clarysse Laurens J Ceulemans Lucas Wauters Nicholas Gilbo Viktor Capiau Gert De Hertogh Wim Laleman Chris Verslype Diethard Monbaliu Jacques Pirenne Tim Vanuytsel | 2022 | World Journal of Transplantation2022，12，4： | 0 |
| 15 | Electrical and optical characteristics of highly transparent MOVPE-grown AlGaN-based tunnel heterojunction LEDs emitting at 232 nm显示文摘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 tunneling.The 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 surface.After 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. | FRANK MEHNKE CHRISTIAN KUHN MARTIN GUTTMANN LUCA SULMONI VERENA MONTAG JOHANNES GLAAB TIM WERNICKE MICHAEL KNEISSL | 2021 | Photonics Research2021，9，6： | 0 |
| 16 | 创智天地 中国上海显示文摘位于城市东北部的杨浦区在上海发展成为技术与科研中心的进程中扮演着极为重要的角色。区内有17所大学和无数的初创企业,如同美国加州的硅谷,杨浦区充满了高度的合作精神和创业的能量与活力。SOM为该区的创智天地提供了总体规划。规划方案涵盖了科研、商业、办公、以及文化元素的设计,旨在打造一个生机勃勃的社区,让新的创意不断涌现并投入市场。 | Tim Griffith(摄影) Dave Burk(摄影) Lucas Blair Simpson(摄影) 无 | 2022 | 世界建筑导报2022，37，6： | 0 |
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