Recherche

Afficher tous les résultats pour

Accueil

Personne

Denis Martin

Cette personne a quitté l’EPFL

À propos
Confidentialité
Mentions légales

Graph Chatbot

Publications associées (34)

Page 2 sur 2

Low p-type contact resistance by field-emission tunneling in highly Mg-doped GaN

Nicolas Grandjean, Denis Martin

Mg-doped GaN with a net acceptor concentration (NA-ND) in the high 10 19 cm(-3) range was grown using ammonia molecular-beam epitaxy. Electrical properties of NiO contact on this heavily doped p-type GaN were investigated. A potential-barrier height of 0.2 ...

Amer Inst Physics2016

M-Plane GaN Grown on m-Plane Sapphire by Hydride Vapor Phase Epitaxy

Nicolas Grandjean, Denis Martin

M-plane GaN epilayers have been directly grown on m-plane sapphire substrates by hydride vapor phase epitaxy using a low temperature GaN nucleation layer. The m-plane GaN surface is optically smooth and mirror-like, with rms roughness similar to 2.0 nm (5 ...

2009

In-Plane Polarities of Nonpolar Wurtzite Epitaxial Films Deposited on m- and r-plane Sapphire Substrates

Nicolas Grandjean, Denis Martin

The in-plane polarities of GaN and ZnO non-polar films deposited on r- and m-sapphire are compared. The polarity is unique on r-sapphire and mixed on m-sapphire because the direction on the substrate surface parallel to the wurztite c-direction is polar in ...

2009

a-plane GaN grown on r-plane sapphire substrates by hydride vapor phase epitaxy

Nicolas Grandjean, Raphaël Butté, Denis Martin

Thin a-plane (1 1 2 0) GaN layers have been grown on r-plane (1 1 0 2) sapphire substrates by hydride vapor phase epitaxy (HVPE), using either a single-step high-temperature (HT) growth or a two-step growth method similar to that of metal organic vapor pha ...

2007

Thermal annealing of molecular beam epitaxy-grown InGaN/GaN single quantum well

Nicolas Grandjean, Denis Martin, Nils Asmus Kristian Kaufmann

The effect of thermal annealing on In0.25Ga0.75N/GaN quantum wells grown by molecular beam epitaxy at 550 degrees C is investigated. A strong increase in the 300 K photoluminescence (PL) intensity is observed for samples annealed at 880 degrees C, while de ...

Iop Publishing Ltd2012

Investigation of the In composition in InGaN/GaN quantum wells deposited by MOVPE and/or MBE with emission from violet to green

Nicolas Grandjean, Denis Martin, Nils Asmus Kristian Kaufmann

Transmission electron microscopy and photoluminescence investigations have been carried out on a series of quantum wells grown by molecular beam epitaxy and metal organic vapour phase epitaxy. In both cases, the emission wavelength and the peak width agree ...

2011

AlGaN/GaN HEMT on (111) single crystalline diamond

Nicolas Grandjean, Denis Martin

AlGaN/GaN HEMTs have been fabricated directly on (111) oriented single crystal diamond with 1.3 x 10(13) cm(-2) channel sheet charge density and 731 cm(2)/Vs mobility. 0.2 mu m gate length devices showed 0.73 A/mm maximum drain current density and f(T) and ...

2010

High quality thin GaN templates grown by hydride vapor phase epitaxy on sapphire substrates

Nicolas Grandjean, Marc Ilegems, Raphaël Butté, Denis Martin

The growth by hydride vapor phase epitaxy (HVPE) of high quality thin GaN layers (d=8 mu m) on c-plane sapphire substrates with dislocation densities lower than 2x10(8) cm(-2) is demonstrated using a two-step process similar to that of metal organic vapor ...

2006

InGaN based micro light emitting diodes featuring a buried GaN tunnel junction

Nicolas Grandjean, Denis Martin, Marco Malinverni

GaN tunnel junctions (TJs) are grown by ammonia molecular beam epitaxy. High doping levels are achieved with a net acceptor concentration close to similar to 10(20) cm(-3), thanks to the low growth temperature. This allows for the realization of p-n juncti ...

Amer Inst Physics2015

Nonpolar GaN-based microcavity using AlN/GaN distributed bragg reflector

Nicolas Grandjean, Eric Feltin, Raphaël Butté, Denis Martin, Gabriel Christmann

Nonpolar GaN based microcavity (MC) made of a bottom AlN/GaN distributed Bragg reflector (DBR) and a top dielectric SiO2/SiNx DBR has been fabricated on a-plane GaN template. The 13 pair AlN/GaN DBR, centered around 372 nm, exhibits a peak reflectivity of ...

2008

Stabilisation of the gravity structure of the Romanesque Abbey of Payerne Switzerland

Eugen Brühwiler, Denis Martin

2017

Critical impact of Ehrlich-Schwobel barrier on GaN surface morphology during homoepitaxial growth

Nicolas Grandjean, Denis Martin, Lise Lahourcade, Nils Asmus Kristian Kaufmann

We discuss the impact of kinetics, and in particular the effect of the Ehrlich-Schwobel barrier (ESB), on the growth and surface morphology of homoepitaxial GaN layers. The presence of an ESB can lead to various self-assembled surface features, which stron ...

Elsevier Science Bv2016

Sputtering of (001)AlN thin films: Control of polarity by a seed layer

Jürgen Brugger, Nicolas Grandjean, Paul Muralt, Jean-François Carlin, Denis Martin, Andreea Veronica Savu, Scott Harada, Evgeny Milyutin

The authors report on the ability to control the polarity of sputter deposited AlN001 thin ﬁlms using seed layers. Reactive sputter deposition leads to N-polarity on any substrate hitherto applied, i.e., Si111, sapphire, SiO2, and polycrystalline metals su ...

American Vacuum Society2010

Si-interdiffusion in heavily doped AlN-GaN-based quantum well intersubband photodetectors

Nicolas Grandjean, Denis Martin, Joab Di Francesco

We demonstrate the effect of rapid thermal annealing on heavily Si-doped AlN/GaN quantum wells. After 1000 degrees C annealing during 5, 10, and 20 min, the dominant effect was interdiffusion of Si rather than intermixing between the Al and Ga atoms. Both ...

AIP American Institute of Physics2011