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GANEX III-N Newsletter Newsletter No. 81 October 2019 GANEX III-N Technology Coordinated by CRHEA-CNRS research laboratory, this monthly newsletter is produced by Knowmade with collaboration from the managers of GANEX groups. The newsletter presents a selection of newest scientific publications, patent applications and press releases related to III- Nitride semiconductor materials (GaN, AlN, InN and alloys) All issues on www.ganex.fr in Veille section. Free subscription http://www.knowmade.com/ganex GANEX Cluster of Excellence (Labex, 2012-2019) GANEX is a cluster gathering French research teams involved in GaN technology. The objective of GANEX is to strengthen the position of French academic players in terms of knowledge and visibility, and reinforce the French industrials in terms of know-how and market share. www.ganex.fr KnowMade KnowMade is a Technology Intelligence and IP Strategy consulting company specialized in analysis of patents and scientific information. The company supports R&D organizations, industrial companies and investors in their business development by helping them to understand their competitive environment, follow technology trends, and find out opportunities and threats in terms of technology and patents. Knowmade operates in the following industrial sectors: Compound Semiconductors, Power Electronics, RF & Microwave Technologies, LED/OLED Lighting & Display, Photonics, Memories, MEMS & Sensors, Manufacturing & Advanced packaging, Batteries & Energy management, Biotechnology, Pharmaceuticals, Medical Devices, Medical Imaging, Agri-Food & Environment. Knowmade’s experts provide prior art search, patent landscape analysis, scientific literature analysis, patent valuation, IP due diligence and freedom-to-operate analysis. In parallel the company proposes litigation/licensing support, technology scouting and IP/technology watch service. Knowmade’s analysts combine their technical and patent expertise by using powerful analytics tools and proprietary methodologies to deliver relevant patent analyses and scientific reviews. www.knowmade.com METHODOLOGY Sources 10+ scientific journal editors Elsevier, IOP, IEEE, Wiley, Springer, APS, AIP, AVS, ECS, Nature, Science … 10+ specialist magazines Semiconductor Today, ElectoIQ, i-micronews, Compound Semiconductor, Solid State Technology … 5+ open access database: FreeFulPDF, DOAJ … Patent database: Questel-Orbit Each month 150+ new scientific publications 200+ new patent applications 30+ new press releases Selection by III-N French experts GANEX monthly newsletter GaNEX | III-N Technology Newsletter No. 81 | 2 TABLE OF CONTENTS (clickable links to chapters) SCIENTIFIC PUBLICATIONS ............................................................................................................................. 4 GROUP 1 - LEDs and Lighting ................................................................................................................................. 4 GROUP 2 - Laser and Coherent Light ................................................................................................................... 12 GROUP 3 - Power Electronics .............................................................................................................................. 14 GROUP 4 - Advanced Electronics and RF ............................................................................................................. 23 GROUP 5 – MEMS and Sensors............................................................................................................................ 29 GROUP 6 - Photovoltaics and Energy harvesting................................................................................................. 34 GROUP 7 - Materials, Technology and Fundamental .......................................................................................... 38 PRESS RELEASE ............................................................................................................................................ 51 PATENT APPLICATIONS ................................................................................................................................ 75 GaNEX | III-N Technology Newsletter No. 81 | 3 SCIENTIFIC PUBLICATIONS Selection of new scientific articles GROUP 1 - LEDs and Lighting Group leader: Benjamin Damilano (CRHEA-CNRS) Information selected by Benjamin Damilano and Mathieu Leroux (CRHEA-CNRS) Size-independent peak efficiency of III-nitride micro- demonstrate localized-surface-plasmon (LSP)- light-emitting-diodes using chemical treatment and enhanced GaN:Eu-based red LEDs utilizing Ag sidewall passivation nanoparticles (NPs) as one of the approaches to Materials Department, University of California, Santa enhance the output power. Size-controllable NPs are Barbara, CA, 93106, United States of America formed by Ag deposition on the GaN:Eu followed by Department of Electrical and Computer Engineering, thermal annealing. The photoluminescence intensity University of California, Santa Barbara, CA, 93106, United of the GaN:Eu LEDs with the NPs increases by 340% States of America compared to those without the NPs. A shorter emission lifetime of the LEDs with the NPs Applied Physics Express https://doi.org/10.7567/1882-0786/ab3949 demonstrates the coupling of Eu3+ ions to the LSPs. Furthermore, the LEDs with the NPs show an Micro-light-emitting-diodes (μLEDs) with size- enhancement of the output power of 210% under independent peak external quantum efficiency current injection due to LSP coupling. behavior was demonstrated from 10 × 10 μm2 to 100 × 100 μm2 by employing a combination of chemical Influence of substrate off-cut angle on the treatment and atomic-layer deposition (ALD) sidewall performance of 310 nm light emitting diodes passivation. The chemical treatment and sidewall Ferdinand-Braun-Institut, Leibniz-Institut für passivation improved the ideality factors of μLEDs Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany from 3.4 to 2.5. The results from the combination of UVphotonics NT GmbH, Gustav-Kirchhoff-Straße 4, 12489 chemical treatment and ALD sidewall passivation Berlin, Germany suggest the issue of size dependent efficiency can be Technische Universität Berlin, Institute of Solid State resolved with proper sidewall treatments after dry Physics, Hardenbergstraße 36, 10623 Berlin, Germany etching. Humboldt University of Berlin, Institute of Physics, Newtonstraße 15, 12489 Berlin, Germany Localized-surface-plasmon-enhanced GaN:Eu-based red light-emitting diodes utilizing silver Journal of Crystal Growth nanoparticles https://doi.org/10.1016/j.jcrysgro.2019.125241 Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, The influence of the sapphire substrate off-cut angle Suita, Osaka 565-0871, Japan from c-plane orientation on the surface morphology of AlN/AlGaN layers and the performance of 310 nm Applied Physics Express light emitting diode structures has been investigated. https://doi.org/10.7567/1882-0786/ab37b0 Increasing the off-cut angle from 0.1° to 10° towards the m-plane leads to a change of the (Al,Ga)N growth GaN:Eu-based red light-emitting diodes (LEDs), mode, threading dislocation density, and emission characterized by spectrally stable and narrow- characteristics of ultraviolet light emitting diodes wavelength operation, have recently reached output- (LEDs). The growth mode changed from step-flow powers respectable for commercialization. Further with bilayer steps to step-bunching and finally to enhancement of Eu3+ luminescence is currently rough 3D growth. The lowest threading dislocation being pursued in order to facilitate their density has been observed for structures deposited implementation into next-generation applications, on sapphire with an off-cut angle of 0.65°, whereas such as micro-LED displays. In this letter, we the emission power is the highest for structures GaNEX | III-N Technology Newsletter No. 81 | 4 grown on substrates with an off-cut of 0.48°. On-chip GaN-based dual-color micro-LED arrays and Electroluminescence measurements display single their application in visible light communication peaks for structures on substrates with off-cut angles Institute of Photonics, Department of Physics, University of of up to 0.65°. The emission peak full width at half Strathclyde, Glasgow G1 1RD, UK maximum remains nearly constant (∼ 9.5 nm) for Institute for Digital Communications, Li–Fi R&D Centre, structures with off-cut angels up to 0.21° and University of Edinburgh, Edinburgh EH9 3JL, UK increases to 11.7 nm and 21.0 nm for 0.48° and 0.65°, Optics Express respectively. The emission wavelength is almost https://doi.org/10.1364/OE.27.0A1517 unchanged by the use of off-cut angles up to 0.48° (311 nm) and increases to 319 nm for 0.65°. Larger Integrated multi-color micron-sized light emitting off-cut angles cause multiple emission peaks diode (micro-LED) arrays have been demonstrated in indicating compositional inhomogeneity of the recent years for display applications; however, their InAlGaN quantum wells. potential as visible light communication (VLC) transmitters is yet to be fully explored. In this work, Enhanced performance of vertical-structured InGaN we report on the fabrication and characterization of micro-pixelated light-emitting-diode array on-chip dual-color micro-LED arrays and their fabricated using an ion implantation process application in VLC. For this purpose, blue-green and Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese blue-violet
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