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3. Localized Epitaxial Growth of 402 V Breakdown Voltage Quasi‐Vertical GaN‐on‐Si p‐n Diode on 200 mm‐Diameter Wafers.

Author

Kaltsounis, Thomas, El Amrani, Mohammed, Plaza Arguello, David, El Rammouz, Hala, Maurya, Vishwajeet, Lafossas, Matthieu, Torrengo, Simona, Haas, Helge, Mendizabal, Laurent, Gueugnot, Alain, Mariolle, Denis, Jalabert, Thomas, Buckley, Julien, Cordier, Yvon, and Charles, Matthew

Subjects
SCHOTTKY barrier diodes, GALLIUM nitride, EPITAXY, DOPING agents (Chemistry), HIGH voltages
Abstract

Localized epitaxy of gallium nitride (GaN) on silicon (Si) wafers is an efficient way to relax elastically the tensile stress generated in the GaN layer after growth, allowing epitaxy of thick layers for the fabrication of vertical power devices operating at high voltage. In this study, a 4.7 μm‐thick GaN layer is grown by metal–organic vapor phase epitaxy on 200 mm‐diameter Si wafers for the fabrication of quasi‐vertical Schottky and p‐n diodes. The uniformity of the doping concentration in the layer is mapped spatially by scanning spreading resistance microscopy, while scanning capacitance microscopy illustrates the differently doped regions in the p‐n diode. The net doping concentration is extracted by capacitance–voltage (C–V) measurements and it is found to be about 3 × 1016 cm−3. On a 140 μm‐diameter quasi‐vertical p‐n diode, destructive breakdown occurs at 402 V, with no periphery protection on the device, demonstrating that localized epitaxy of GaN on Si has great potential for vertical high‐power devices. [ABSTRACT FROM AUTHOR]

Published
2024
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4. Contacting individual Fe(110) dots in a single electron-beam lithography step

Author

Cheynis, Fabien, Haas, Helge, Fournier, Thierry, Ranno, Laurent, Wernsdorfer, Wolfgang, Fruchart, Olivier, and Toussaint, Jean-Christophe

Subjects
Condensed Matter - Materials Science
Abstract

We report on a new approach, entirely based on electron-beam lithography technique, to contact electrically, in a four-probe scheme, single nanostructures obtained by self-assembly. In our procedure, nanostructures of interest are localised and contacted in the same fabrication step. This technique has been developed to study the field-induced reversal of an internal component of an asymmetric Bloch domain wall observed in elongated structures such as Fe(110) dots. We have focused on the control, using an external magnetic field, of the magnetisation orientation within N\'eel caps that terminate the domain wall at both interfaces. Preliminary magneto-transport measurements are discussed demonstrating that single Fe(110) dots have been contacted., Comment: 5 pages

Published
2009
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6. Electrical behavior of vertical Pt/Au Schottky diodes on GaN homoepitaxy

Author

Dagher, Maroun, primary, Sonneville, Camille, additional, Brémond, Georges, additional, Planson, Dominique, additional, Frayssinet, Eric, additional, Cordier, Yvon, additional, Haas, Helge, additional, Iretki, Mohammed Reda, additional, Buckley, Julien, additional, Maurya, Vishvajeet, additional, Charles, Matthew, additional, and Bluet, Jean-Marie, additional

Published
2023
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8. Gallium nitride power devices for power conversion applications

Author

Buckley, Julien, Escoffier, René, Mohamad, Blend, Becu, Stéphane, Biscarrat, Jérôme, Rigaud-Minet, Florian, Vauche, Laura, Maurya, Vishwajeet, Charles, Matthew, Haas, Helge, Fayolle-Lecocq, Murielle, Martin, Jérémy, Nguyen, Van-Sang, Le Royer, Cyrille, Gwoziecki, Romain, Gillot, Charlotte, Sousa, Véronique, Département Composants Silicium (DCOS), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'Innovation pour les Technologies des Energies Nouvelles et les nanomatériaux (LITEN), Institut National de L'Energie Solaire (INES), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics
Abstract

International audience; This presentation will deal with our work on gallium nitride (GaN) devices for power electronics. The breakdown field of GaN is around 3.3 MV/cm and its mobility can surpass 1000 cm²/V.s, making it an excellent candidate for power switches. The lateral HEMT (High Electron Mobility Transistor) architecture using GaN epitaxy on Silicon is increasingly successful, especially for applications at 650V or below. GaN free-standing wafers are also being used to develop components with a vertical geometry which leads to higher power density due to volume instead of surface conduction.We have developed lateral normally-off GaN-on-Si MOSc-HEMTs (Metal Oxide Semiconductor channel HEMTs). Their advantage comes from the insulated gate technology results in extremely low gate current and a reduced temperature coefficient of its On-resistance, both of which are beneficial for the design of power converters. We will present a full micro inverter using our 100V and 650V MOSc-HEMTs for inclusion on an individual solar panel (DC 45V / AC 230V). The talk will also cover alternative lateral and vertical device architectures that can allow GaN to address new power conversion applications.

Published
2022

9. Electrical behavior of vertical Schottky diodes on GaN homoepitaxy

Author

Dagher, M, Sonneville, Camille, Bremond, Georges, Planson, Dominique, Cordier, Yvon, Haas, Helge, Iretki, M, Buckley, Julien, Maurya, V, Charles, M, Bluet, Jean-Marie, Ampère, Département Energie Electrique (EE), Ampère (AMPERE), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), INL - Matériaux Fonctionnels et Nanostructures (INL - MFN), Institut des Nanotechnologies de Lyon (INL), Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur l'hétéroepitaxie et ses applications (CRHEA), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université Côte d'Azur (UCA), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
[SPI.NRJ]Engineering Sciences [physics]/Electric power
Abstract

International audience

Published
2022

10. Influence of Fluorine implantation on the electrical characteristics of GaN-on-GaN vertical Schottky and P-N diodes

Author

Maurya, Vishwajeet, Buckley, Julien, Haas, Helge, Irekti, Mohamed Reda, Charles, Matthew, Sonneville, Camille, Alquier, Daniel, Sousa, Véronique, Département Composants Silicium (DCOS), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Ampère, Département Automatique pour l'Ingénierie des Systèmes (AIS), Ampère (AMPERE), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-École Centrale de Lyon (ECL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), GREMAN (matériaux, microélectronique, acoustique et nanotechnologies) (GREMAN - UMR 7347), Université de Tours (UT)-Institut National des Sciences Appliquées - Centre Val de Loire (INSA CVL), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics
Abstract

International audience; GaN-based power devices have been gaining popularity in recent years thanks to GaN properties such as wide bandgap, high electron mobility, and high breakdown field strength, allowing low Ron, and high-frequency operation. Lateral GaN devices, which are grown on a foreign substrate like Si and sapphire [1], have already been commercialized and have been able to achieve much better performance compared to their silicon counterparts. However, these devices are unable to achieve sufficiently high breakdown voltage (BV>1kV). One alternative to boost the breakdown voltage and lower Ron is to have vertical devices grown on a native GaN substrate. These devices still suffers from premature breakdown and high reverse leakage due to electric field crowding at the junction edge. This issue can be resolved by creating an effective edge termination either by using Mg implantation [2] to create a p-doped region or by alternate species implantation by Nitrogen [3] or Argon [4] to create a resistive region at the junction edge. However, due to the difficulty in creating p-GaN by ion implantation due to compensation by Hydrogen and large activation energy of ~170 meV, alternate species of implantation is preferred. Fluorine ion implantation [5] is an attractive alternative as it can form a negative fixed charge owning to its highest electronegativity thus spread the electric field away from the contact and can also modulate the free charge carrier in GaN.In this study, P-N and Schottky structures are fabricated using multi energy Fluorine implantation as an edge termination. The influence of the implant on the electrical characteristics is studied by varying the implant overlap beneath the contact. µ-Raman scanning of the device suggests a reduction in free charge concentration in the implanted region, and an increase in the built-in potential obtained through C-V measurements compared to the device with no implantation. The influence of implantation on the electrical characteristics (B-V, I-V, and C-V) is analyzed and TCAD simulations using Synopsys® SentaurusTM are performed to help interpret the results.

Published
2022

11. Full InGaN red (625 nm) micro-LED (10 μm) demonstration on a relaxed pseudo-substrate

Author

Dussaigne, Amelie, primary, Le Maitre, Patrick, additional, Haas, Helge, additional, Pillet, Jean-Christophe, additional, Barbier, Frederic, additional, Grenier, Adeline, additional, Michit, Nicolas, additional, Jannaud, Audrey, additional, Templier, Roselyne, additional, Vaufrey, David, additional, Rol, Fabian, additional, Ledoux, Olivier, additional, and Sotta, David, additional

Published
2021
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15. Investigation of p-contact performance for indium rich InGaN based light emitting diodes and solar cells

Author

Alam, Saiful, Sundaram, Suresh, Haas, Helge, Li, Xin, El Gmili, Youssef, Jamroz, Miryam, Robin, Ivan, Voss, Paul, Salvestrini, Jean-Paul, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Ecole Supérieure d'Electricité - SUPELEC (FRANCE)-Georgia Institute of Technology [Atlanta]-CentraleSupélec-Ecole Nationale Supérieure des Arts et Metiers Metz-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI]Engineering Sciences [physics], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2017
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19. New Field Effect Deep‐UV μLEDs Development.

Author

Rottner, Jean, Haas, Helge, Largeron, Christophe, Vaufrey, David, and Robin, Ivan. C.

Subjects
*FIELD-effect devices, *ULTRAVIOLET radiation, *LIGHT emitting diodes, *ALUMINUM gallium nitride, *DOPING agents (Chemistry)
Abstract

Mg‐doped AlGaN layers are needed for deep‐ultraviolet light emitting diodes (DUV‐LEDs). However because of the high activation energy of Mg in such layers, the ionization level of the Mg‐dopants is very low. In this paper a new design is proposed with a view to improve the wall plug efficiency (WPE) of DUV‐LEDs. The method consists in using a geometry combining a UV‐μLED and a gate covering the edges of the mesa. This approach is intended to by‐pass the problem of low ionization level of the dopants in p‐AlGaN. The simulated structures include a DUV‐LED mesa structure with Al0.5Ga0.5N/Al0.7Ga0.3N multiple quantum well (MQW) active region emitting around 265 nm. It also comprises a gate deposited on the sidewalls of the mesa. Simulations performed with Silvaco atlas will be presented. In particular we will show that by applying an appropriate voltage to the gate, holes can be efficiently injected into the active region. They reach the active region via an accumulation channel below the gate around the mesa, and then diffuse along the length of wells and easily recombine with electrons. Finally simulations show that the calculated WPE can be increased by a factor of 3 for an optimized structure geometry. [ABSTRACT FROM AUTHOR]

Published
2018
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22. 16.2: Invited Paper:Challenges and solutions for High‐performance GaN MicroLED displays

Author

Templier, F., Bernard, J., Caplet, S., Bédoin, A., and Haas, Helge

Abstract

We discuss the main challenges for the fabrication of emerging microLED displays. We shown that microtube technology is very well adapted to these new kind of displays, since it provides both mechanical and electrical connection of the microLEDs on the receiving substrate. Also, we present a new fabrication approach, where an elementary unit consists of all‐in‐one‐ RBG MicroLEDs on CMOS driving circuit.

Published
2019
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24. Investigation of p‐contact performance for indium rich InGaNbased light emitting diodes and solar cells

Author

Alam, Saiful, Sundaram, Suresh, Haas, Helge, Li, Xin, El Gmili, Youssef, Jamroz, Miryam E., Robin, Ivan C., Voss, Paul L., Salvestrini, Jean‐Paul, and Ougazzaden, Abdallah

Abstract

We report on the optimization of p‐GaN layers for high indium (In) content InGaN applications by optimizing temperature, precursor CP2Mg flow rate and III/V ratio and report also on the optimization of p‐contact performance. Using MOVPE, a 150 nm thick p‐type GaN with moderate Mg doping and a 50 nm contact layer with high Mg doping concentration were grown on standard GaN templates at growth temperatures in the range of 850–1000 °C. Hall measurement yields hole concentration of 4.8 × 1017cm−3for the optimized sample. SIMS shows Mg concentration of 1.7 × 1020cm−3on average in the heavily doped and 4 × 1019cm−3on average in the moderately doped p‐GaN layer for the optimized p‐GaN. A multilayer Pd/Ag/Ni/Au metal contact has been deposited on this p‐GaN and studied using the CTLM technique. Optimization of both p‐GaN layers and p‐contact processing led to a low resistance contact with specific contact resistivity of 6 × 10−4Ω cm2. We believe, the very high Mg concentration of the surface layer in intimate contact with the contact metal reduces the Schottky barrier height and band bending. This optimization of p‐GaN is an important step towards high efficiency green LEDs and solar cells.

Published
2017
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