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3. Model of Ni-63 battery with realistic PIN structure.

Author

Munson IV, Charles E., Arif, Muhammad, Streque, Jeremy, Belahsene, Sofiane, Martinez, Anthony, Ramdane, Abderrahim, El Gmili, Youssef, Salvestrini, Jean-Paul, Voss, Paul L., and Ougazzaden, Abdallah

Subjects
ELECTRON-hole droplets, ELECTRIC batteries, ENERGY development, SCANNING electron microscopes, RADIOACTIVE substances
Abstract

GaN, with its wide bandgap of 3.4 eV, has emerged as an efficient material for designing high-efficiency betavoltaic batteries. An important part of designing efficient betavoltaic batteries involves a good understanding of the full process, from the behavior of the nuclear material and the creation of electron-hole pairs all the way through the collection of photo-generated carriers. This paper presents a detailed model based on Monte Carlo and Silvaco for a GaN-based betavoltaic battery device, modeled after Ni-63 as an energy source. The accuracy of the model is verified by comparing it with experimental values obtained for a GaN-based p-i-n structure under scanning electron microscope illumination. [ABSTRACT FROM AUTHOR]

Published
2015
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4. 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

5. Influence of barrier layer indium on efficiency and wavelength of InGaN multiple quantum well (MQW) with and without semi-bulk InGaN buffer for blue to green regime emission

Author

Alam, Saiful, Sundaram, Suresh, Li, Xin, Jamroz, Miryam, El Gmili, Youssef, Robin, Ivan, Voss, Paul, Salvestrini, Jean-Paul, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Ecole Nationale Supérieure des Arts et Metiers Metz-Georgia Institute of Technology [Atlanta]-Ecole Supérieure d'Electricité - SUPELEC (FRANCE)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), 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), 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
MOVPE, [SPI]Engineering Sciences [physics], III-nitride semiconductors, barrier layer, InGaN, multiple quantum well, light-emitting diodes, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, ComputingMilieux_MISCELLANEOUS, [SPI.TRON]Engineering Sciences [physics]/Electronics
Abstract

International audience; The effect of indium (In) in the barrier of InGaN/GaN multiple quantum well (MQW) has been studied for MQWs with and without semi-bulk InGaN buffer. From simulation, the optimum In content in the barrier with 3–5 nm width is 5–7% to get the optimal material quality and internal quantum efficiency (IQE) of ∼65% for 450–480 nm emission range. Simulation shows a reduction of the potential barrier due to band flattening, a more homogeneous distribution of electrons and holes in the active region and subsequently, a more radiative recombination rate with InGaN as barrier layer. Both cathodoluminescence (CL) and photoluminescence (PL) experimental results show a blue-shift of emission wavelength along with an enhancement in the emission intensity when GaN barrier is replaced with InGaN barrier, for a MQW structure both with and without the semi-bulk InGaN buffer. We attribute this blue shift to the reduced polarization mismatch and increased effective bandgap. This InGaN barrier-related improvement in IQE and efficiency droop could be useful for the realization of longer wavelength “green-gap” range LEDs where poor IQE and efficiency droop are more prominent due to high indium (In) in the active region.

Published
2017

9. Nanometer scale characterizations of InGaN nanostructures grown on GaN template

Author

El Gmili, Youssef, Sundaram, Suresh, Puybaret, Renaud, Li, Xin, Bonanno, Peter, Pradalier, Cedric, Voss, Paul L, Salvestrini, Jean-Paul, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Université de Franche-Comté (UFC), 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), Laboratoire d'Informatique de Grenoble (LIG), Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS), Autonomous Systems Laboratory (BIOMEDIA), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), CSIRO Information and Commuciation Technologies (CSIRO ICT Centre), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), and CentraleSupélec-Université de Lorraine (UL)

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

10. Nanoselective area growth of high quality thick InGaN/GaN on sacrificial ZnO templates

Author

Puybaret, Renaud, Sundaram, Suresh, Li, Xin, El Gmili, Youssef, Pantzas, Konstantinos, Troadec, David, Patriarche, Gilles, Rogers, David, Teherani, Ferechteh Hosseini, Sandana, Eric Vinod, Bove, Philippe, Voss, Paul L, Salvestrini, Jean-Paul, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Université de Franche-Comté (UFC), 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), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Nanovation SARL, Laboratoire des Solides Irradiés (LSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), ANR-12-PRGE-0014,NOVAGAINS,Nouvelles cellules photovoltaïques tandem à base de nitrures d'indium et de gallium sur oxyde de zinc sur silicium(2012), Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec-Georgia Institute of Technology [Lorraine, France]-Georgia Institute of Technology [Atlanta]-Ecole Supérieure d'Electricité - SUPELEC (FRANCE)-Ecole Nationale Supérieure des Arts et Metiers Metz-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Institut d’Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520 (IEMN), Ecole Centrale de Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), UMI GT CNRS, Georgia Institute of Technology [Atlanta]-Centre National de la Recherche Scientifique (CNRS), Salvestrini, Jean Paul, Production renouvelable et gestion de l’électricité - Nouvelles cellules photovoltaïques tandem à base de nitrures d'indium et de gallium sur oxyde de zinc sur silicium - - NOVAGAINS2012 - ANR-12-PRGE-0014 - PROGELEC - VALID, Ecole Nationale Supérieure des Arts et Metiers Metz-Georgia Institute of Technology [Atlanta]-Ecole Supérieure d'Electricité - SUPELEC (FRANCE)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

11. High quality thick InGaN nanostructures grown by nanoselective area growth for new generation photovoltaic devices

Author

Suresh, Sundaram, Puybaret, Renaud, Li, Xin, El Gmili, Youssef, Streque, Jérémy, Pantzas, Konstantinos, Orsal, Gaelle, Patriarche, Gilles, L. Voss, P., Salvestrini, Jean-Paul, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Université de Franche-Comté (UFC), 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), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), UMI GT CNRS, and Georgia Institute of Technology [Atlanta]-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

12. MOVPE growth of InGaN alloys with high In content on ZnO template substrates

Author

Sundaram, Suresh, Puybaret, Renaud, Rogers, Dave J., Teherani, Ferechteh Hosseini, Sandana, Eric Vinod, Bove, Philippe, El Gmili, Youssef, Troadec, David, Patriarche, Gilles, Voss, Paul L, Salvestrini, Jean-Paul, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Ecole Nationale Supérieure des Arts et Metiers Metz-Georgia Institute of Technology [Atlanta]-Ecole Supérieure d'Electricité - SUPELEC (FRANCE)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Nanovation SARL, Laboratoire des Solides Irradiés (LSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), ANR-12-PRGE-0014,NOVAGAINS,Nouvelles cellules photovoltaïques tandem à base de nitrures d'indium et de gallium sur oxyde de zinc sur silicium(2012), Université de Franche-Comté (UFC), 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), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Salvestrini, Jean Paul, and Production renouvelable et gestion de l’électricité - Nouvelles cellules photovoltaïques tandem à base de nitrures d'indium et de gallium sur oxyde de zinc sur silicium - - NOVAGAINS2012 - ANR-12-PRGE-0014 - PROGELEC - VALID

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

13. Selective area growth of III-nitrides using epitaxial graphene as a mask : towards fully integrated III-nitride / graphene / SiC electronics and optoelectronics

Author

Puybaret, Renaud, Sundaram, Suresh, El Gmili, Youssef, Jordan, Matthew, Salvestrini, Jean-Paul, Voss, Paul L, De Heer, Walter, Berger, Claire, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Université de Franche-Comté (UFC), 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), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Georgia Institute of Technology [Atlanta], and Salvestrini, Jean Paul

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2015

14. AlGaN-based multi-quantum wells emitting at 285 nm grown on a thick AlGaN relaxed buffer on AlN template

Author

Li, Xin, Sundaram, Suresh, El Gmili, Youssef, Moudakir, Tarik, Disseix, Pierre, Réveret, François, Leymarie, Joël, Bouchoule, Sophie, Genty, Frédéric, Salvestrini, Jean-Paul, Voss, Paul L, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Université de Franche-Comté (UFC), 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), Institut Pascal (IP), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-SIGMA Clermont (SIGMA Clermont)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Van Luchene, Sébastien, Ecole Nationale Supérieure des Arts et Metiers Metz-Georgia Institute of Technology [Atlanta]-Ecole Supérieure d'Electricité - SUPELEC (FRANCE)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)

Subjects
[SPI]Engineering Sciences [physics], [SPI] Engineering Sciences [physics], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

15. BAlN thin layers for deep UV applications

Author

Li, Xin, Sundaram, Suresh, El Gmili, Youssef, Genty, Frédéric, Voss, Paul L, Salvestrini, Jean-Paul, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Ecole Nationale Supérieure des Arts et Metiers Metz-Georgia Institute of Technology [Atlanta]-Ecole Supérieure d'Electricité - SUPELEC (FRANCE)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Van Luchene, Sébastien, 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
[PHYS]Physics [physics], [PHYS] Physics [physics]
Abstract

International audience; Boron containing III-nitrides are attractive system for deep-UV LEDs and LDs because of their wide bandgaps and flexible lattice. However the crystallinity and boron content have been limited due to large mismatch between BN and other nitrides. In this work, BAlN layers with boron composition from 1% to 5% were successfully grown on AlN template substrates by low-pressure organometallic vapor phase epitaxy. The samples were grown at 650˚C and then annealed at 1020˚C for recrystallization. Growth techniques such as temperature, growth time and TEB/III ratio in the gas phase were investigated. High quality BAlN layers were grown using flow-modulate epitaxy method that allows to enhance surface migration of boron atoms. 70 nm-thick layers show a good surface morphology. For the first time, clear XRD peak relating to 5% boron for this new material was observed, which suggests the formation of single-phase solid solution. Adding more boron to the AlN produced a shift in the peak positions to greater angles. Further results by TEM and optical characterizations will be presented. This new material is promising for deep-UV applications and gives more freedom for bandgap engineering of multi-structure devices.

Published
2014

16. Bandgap energy bowing parameter of strained and relaxed InGaN layers

Author

Orsal, Gaëlle, El Gmili, Youssef, Fressengeas, Nicolas, Streque, Jérémy, Djerboub, Ryad, Moudakir, Tarik, Suresh, Sundaram, Ougazzaden, Abdallah, Salvestrini, Jean-Paul, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), 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
optical properties, OCIS: 310.6860, 120.0120, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Thin films, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Instrumentation, measurement and metrology
Abstract

International audience; This paper focuses on the determination of the bandgap energy bowing parameter of strained and relaxed InxGa1−xN layers. Samples are grown by metal organic vapor phase epitaxy on GaN template substrate for indium compositions in the range of 0

Published
2014

17. Étude et caractérisations par cathodoluminescence de couches minces d'InGaN pour le photovoltaïque

Author

El Gmili, Youssef, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Université de Lorraine, Abdallah Ougazzaden, and Jean-Paul Salvestrini

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, InGaN, Cathodoluminescence, Systèmes photovoltaïques, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Photovoltaïque, Semiconducteurs à large bande interdite, Nitrure de gallium
Abstract

GaN and its ternary and quaternary alloys Ga(B, In, Al)N have become in recent years one of the most important semiconductor materials for applications in optoelectronics. More specifically, the InGaN alloy, that has a band gap energy (0.77eV for InN, 3.4eV for GaN) allowing almost full absorption of the visible spectrum can be an excellent candidate for the realization of highly efficient multi-junctions solar cells. However, the growth of InGaN epitaxial layers with high indium content and good structural and morphological quality remains a challenge. Our group was among the first to meet this challenge by proposing an original growth technique consisting in the periodical insertion of thin GaN layers in the thick InGaN layer. The present work falls in this context and focuses on the morphological, structural and optical characterization of different InGaN structures that have been developed, allowing the optimization of the growth process and the obtention of InGaN layers with an indium content of 15%, a thickness of 120nm and a high structural and optical quality. The main aspect of the present work consist in the implementation and use of the cathodoluminescence technique to study the InGaN materials grown by our group using MOVPE. The main achievements of this work, in addition to the contribution to the success of getting high quality InGaN layers, relate to the confirmation of the growth mode of InGaN layers (2D - 3D transition, type and role of surface inclusions), the determination of the critical layer thickness according to the indium content, and the modeling of the cathodoluminescence phenomenon using Monte Carlo method; GaN et ses alliages ternaires et quaternaires du système Ga(B,In,Al) sont devenus au cours des dernières années des semiconducteurs phare de l'optoélectronique. Plus spécifiquement l'alliage InGaN qui présente une énergie de bande interdite (0, 77eV, pour l'InN à 3, 4eV, pour le GaN) permettant l'absorption quasi totale du spectre visible se positionne comme un excellent candidat pour la réalisation de cellules solaire multi-jonctions à très haut rendement. La croissance de couches épitaxiales d'InGaN avec une forte teneur en indium et une bonne qualité structurale et morphologique reste néanmoins un challenge. Notre groupe a été parmi les premiers à relever ce challenge en proposant une technique de croissance originale consistant à insérer périodiquement de fines couches de GaN dans la couche épaisse d'InGaN. Ce travail s'inscrit dans ce contexte et porte sur les caractérisations morphologiques, structurales et optiques des différentes structures élaborées et qui ont permit l'optimisation du procédé de croissance et l'obtention de couches d'InGaN avec une teneur en indium de 15%, une épaisseur de 120nm et des qualités structurales et optiques de premier ordre. La partie centrale du travail a consisté en la mise en oeuvre et l'utilisation de la technique de cathodoluminescence pour l'étude des matériaux InGaN élaborés au laboratoire par MOVPE. Les principales avancées de ce travail, outre la contribution au succès de l'obtention de couches d'InGaN de grande qualité, concernent la confirmation du mode de croissance des couches d'InGaN (transition 2D-3D, type et rôle des inclusions de surface), la détermination de l'épaisseur critique des couches en fonction du taux d'indium, et la modélisation du phénomène de cathodoluminescence par méthode Monte-Carlo

Published
2013

18. Cathodoluminescence study and characterization of InGaN thin films for photovoltaic

Author

El Gmili, Youssef, Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), Université de Lorraine, Abdallah Ougazzaden, Jean-Paul Salvestrini, and UL, Thèses

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, InGaN, [PHYS.COND.CM-GEN] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], [SPI.OTHER] Engineering Sciences [physics]/Other, Cathodoluminescence, Systèmes photovoltaïques, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Photovoltaïque, Semiconducteurs à large bande interdite, Nitrure de gallium
Abstract

GaN and its ternary and quaternary alloys Ga(B, In, Al)N have become in recent years one of the most important semiconductor materials for applications in optoelectronics. More specifically, the InGaN alloy, that has a band gap energy (0.77eV for InN, 3.4eV for GaN) allowing almost full absorption of the visible spectrum can be an excellent candidate for the realization of highly efficient multi-junctions solar cells. However, the growth of InGaN epitaxial layers with high indium content and good structural and morphological quality remains a challenge. Our group was among the first to meet this challenge by proposing an original growth technique consisting in the periodical insertion of thin GaN layers in the thick InGaN layer. The present work falls in this context and focuses on the morphological, structural and optical characterization of different InGaN structures that have been developed, allowing the optimization of the growth process and the obtention of InGaN layers with an indium content of 15%, a thickness of 120nm and a high structural and optical quality. The main aspect of the present work consist in the implementation and use of the cathodoluminescence technique to study the InGaN materials grown by our group using MOVPE. The main achievements of this work, in addition to the contribution to the success of getting high quality InGaN layers, relate to the confirmation of the growth mode of InGaN layers (2D - 3D transition, type and role of surface inclusions), the determination of the critical layer thickness according to the indium content, and the modeling of the cathodoluminescence phenomenon using Monte Carlo method, GaN et ses alliages ternaires et quaternaires du système Ga(B,In,Al) sont devenus au cours des dernières années des semiconducteurs phare de l'optoélectronique. Plus spécifiquement l'alliage InGaN qui présente une énergie de bande interdite (0, 77eV, pour l'InN à 3, 4eV, pour le GaN) permettant l'absorption quasi totale du spectre visible se positionne comme un excellent candidat pour la réalisation de cellules solaire multi-jonctions à très haut rendement. La croissance de couches épitaxiales d'InGaN avec une forte teneur en indium et une bonne qualité structurale et morphologique reste néanmoins un challenge. Notre groupe a été parmi les premiers à relever ce challenge en proposant une technique de croissance originale consistant à insérer périodiquement de fines couches de GaN dans la couche épaisse d'InGaN. Ce travail s'inscrit dans ce contexte et porte sur les caractérisations morphologiques, structurales et optiques des différentes structures élaborées et qui ont permit l'optimisation du procédé de croissance et l'obtention de couches d'InGaN avec une teneur en indium de 15%, une épaisseur de 120nm et des qualités structurales et optiques de premier ordre. La partie centrale du travail a consisté en la mise en oeuvre et l'utilisation de la technique de cathodoluminescence pour l'étude des matériaux InGaN élaborés au laboratoire par MOVPE. Les principales avancées de ce travail, outre la contribution au succès de l'obtention de couches d'InGaN de grande qualité, concernent la confirmation du mode de croissance des couches d'InGaN (transition 2D-3D, type et rôle des inclusions de surface), la détermination de l'épaisseur critique des couches en fonction du taux d'indium, et la modélisation du phénomène de cathodoluminescence par méthode Monte-Carlo

Published
2013

19. Role of V-pits in the performance improvement of InGaN solar cells

Author

Arif, Muhammad, primary, Salvestrini, Jean-Paul, additional, Streque, Jérémy, additional, Jordan, Matthew B., additional, El Gmili, Youssef, additional, Sundaram, Suresh, additional, Li, Xin, additional, Patriarche, Gilles, additional, Voss, Paul L., additional, and Ougazzaden, Abdallah, additional

Published
2016
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21. Wafer-scale epitaxial lift-off of optoelectronic grade GaN from a GaN substrate using a sacrificial ZnO interlayer

Author

Rajan, Akhil, primary, Rogers, David J, additional, Ton-That, Cuong, additional, Zhu, Liangchen, additional, Phillips, Matthew R, additional, Sundaram, Suresh, additional, Gautier, Simon, additional, Moudakir, Tarik, additional, El-Gmili, Youssef, additional, Ougazzaden, Abdallah, additional, Sandana, Vinod E, additional, Teherani, Ferechteh H, additional, Bove, Philippe, additional, Prior, Kevin A, additional, Djebbour, Zakaria, additional, McClintock, Ryan, additional, and Razeghi, Manijeh, additional

Published
2016
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26. Suppression of Crack Generation in AlGaN/GaN Distributed Bragg Reflector Grown by MOVPE

Author

Moudakir, Tarik, Gautier, Simon, Sundaram, Suresh, Abid, Mohamed, Pantzas, Konstantinos, El Gmili, Youssef, Jacquet, Joël, Genty, Frédéric, Ougazzaden, Abdallah, Georgia Tech Lorraine [Metz], Université de Franche-Comté (UFC), 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), Laboratoire Matériaux Optiques, Photonique et Systèmes (LMOPS), CentraleSupélec-Université de Lorraine (UL), OPTEL - Equipe Optique et électronique pour les télécoms, and Van Luchene, Sébastien

Published
2012

27. High quality thick InGaN nanostructures grown by nanoselective area growth for new generation photovoltaic devices

Author

Sundaram, Suresh, primary, Puybaret, Renaud, additional, Li, Xin, additional, El Gmili, Youssef, additional, Streque, Jeremy, additional, Panztas, Konstantinos, additional, Orsal, Gaelle, additional, Patriarche, Gilles, additional, Voss, Paul L., additional, Salvestrini, Jean Paul, additional, and Ougazzaden, Abdallah, additional

Published
2015
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28. Experimental Study and Device Design of NO, NO2, and NH3 Gas Detection for a Wide Dynamic and Large Temperature Range Using Pt/AlGaN/GaN HEMT.

Author

Bishop, Chris, Halfaya, Yacine, Soltani, Ali, Sundaram, Suresh, Li, Xin, Streque, Jeremy, El Gmili, Youssef, Voss, Paul L., Salvestrini, Jean Paul, and Ougazzaden, Abdallah

Abstract

We report an AlGaN/GaN HEMT gas sensor designed to enable NO, NO2, and NH3 detection from 100 °C–400 °C over a large concentration range. Device modeling is performed to optimize several HEMT device parameters for sensing, and the experimental results show that the optimized sensor has improved performance compared with the previously reported HEMT sensors. The device shows significant no sensitivity for the first time in an HEMT device, with sensitivity up to 7% at 400 °C. In addition, high sensitivities of up to 17% are reported for NO2, and NH3 is detected at concentrations as low as 150 ppb. [ABSTRACT FROM PUBLISHER]

Published
2016
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30. 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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31. Emission wavelength red-shift by using “semi-bulk” InGaN buffer layer in InGaN/InGaN multiple-quantum-well.

Author

Voss, Paul L., Ougazzaden, Abdallah, Alam, Saiful, Sundaram, Suresh, Li, Xin, El Gmili, Youssef, Salvestrini, Jean-Paul, Elouneg-Jamroz, Miryam, Robin, Ivan Christophe, and Patriarche, Gilles

Subjects
*QUANTUM wells, *WAVELENGTHS, *INDIUM gallium nitride, *BUFFER layers, *QUANTUM confined Stark effect, *MOLECULAR relaxation
Abstract

We report an elongation of emission wavelength by inserting a ∼70 nm thick high quality semi-bulk (SB) In y Ga 1-y N buffer layer underneath the In x Ga 1-x N/In y Ga 1-y N (x > y) multi-quantum-well (MQW).While the MQW structure without the InGaN SB buffer is fully strained on the n-GaN template, the MQW structure with the buffer has ∼15% relaxation. This small relaxation along with slight compositional pulling induced well thickness increase of MQW is believed to be the reason for the red-shift of emission wavelength. In addition, the SB InGaN buffer acts as an electron reservoir and also helps to reduce the Quantum Confined Stark Effect (QCSE) and thus increase the emission intensity. In this way, by avoiding fully relaxed buffer induced material degradation, a longer emission wavelength can be achieved by just using InGaN SB buffer while keeping all other growth conditions the same as the reference structure. Thus, a reasonably thick fully strained or very little relaxed InGaN buffer, which is realized by “semi-bulk” approach to maintain good InGaN material quality, can be beneficial for realizing LEDs, grown on top of this buffer, emitting in the blue to cyan to green regime without using excess indium (In). [ABSTRACT FROM AUTHOR]

Published
2017
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