Publications de Marc Ilegems | EPFL Graph Search

Nitride-based heterostructures grown by MOCVD for near- and mid-infrared intersubband transitions

Jean-François Carlin, Marc Ilegems, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Sylvain Nicolay, Mauro Mosca

Intersubband (lSB) optical absorption in different nitride-based heterostructures grown by metal-organic chemical vapour deposition (MOCVD) is reported. The role of indium in AlInN/GaN multi-quantum wells (MQWs) is investigated. At high concentration (15%) ...

Wiley2007

Visible InGaN/GaN quantum-dot materials and devices

Marc Ilegems, Nicolas Grandjean

General properties of III-V nitride-based quantum dots (QDs) are presented, with a special emphasis on InGaN/GaN QDs for visible optoelectronic devices. Stranski-Krastanov GaN/AIN dots are first discussed as a prototypical system. it is shown that the opti ...

2007

Selective etching of AlInN/GaN heterostructures for MEMS technology

Jean-François Carlin, Marc Ilegems, Nicolas Grandjean

An etching technology for the patterning of suspended GaN structures on lattice matched AlInN sacrificial layers is studied. Selective dry RIE etching of GaN to AlInN is demonstrated, which allows effective pattern transfer without affecting lower layers. ...

2007

Stress control in GaN/sapphire templates for the fabrication of crack-free thick layers

Marc Ilegems, Denis Martin, Nicolas Grandjean

The reduction of the tensile stress contained in GaN layers grown oil sapphire by metalorganic vapor phase epitaxy (MOVPE) is achieved using a low density of initial GaN crystallites. The template layers exhibit a significant reduction in dislocation densi ...

2006

Room-temperature polariton luminescence from a bulk GaN microcavity

Jean-François Carlin, Marc Ilegems, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Mauro Mosca, Gabriel Christmann

We report strong exciton-photon coupling at room temperature in a hybrid high quality bulk 3 lambda/2 GaN cavity with a bottom lattice-matched AlInN/AlGaN distributed Bragg reflector through angle-resolved polarized photoluminescence (PL). Coupling of the ...

2006

Indium surfactant effect on AlN/GaN heterostructures grown by metal-organic vapor-phase epitaxy: Applications to intersubband transitions

Jean-François Carlin, Marc Ilegems, Nicolas Grandjean, Eric Feltin, Sylvain Nicolay, Mauro Mosca

We report on a dramatic improvement of the optical and structural properties of AlN/GaN multiple quantum wells (MQWs) grown by metal-organic vapor-phase epitaxy using indium as a surfactant. This improvement is observed using photoluminescence as well as x ...

2006

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

Marc Ilegems, Denis Martin, Nicolas Grandjean, Raphaël Butté

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

Crack-free highly reflective AlInN/AlGaN bragg mirrors for UV applications

Jean-François Carlin, Marc Ilegems, Julien Dorsaz, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Gabriel Christmann

We report the growth of highly reflective distributed Bragg reflectors (DBRs) in the UV region using the Al0.85In0.15N/Al0.2Ga0.8N lattice-matched system. The DBRs were deposited on nearly strain-free Al0.2Ga0.8N templates to avoid strain-induced structura ...

2006

Stranski-Krastanov GaN/AlN quantum dots grown by metal organic vapor phase epitaxy

Jean-François Carlin, Marc Ilegems, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Dobri Simeonov

We report a thorough study of the growth of self-assembled GaN/AlN quantum dots (QDs). These QDs were grown on sapphire substrates using the Stranski-Krastanov (SK) growth mode by means of low-pressure metal organic vapor phase epitaxy. The influence of th ...

2006

Selective oxidation of AlInN layers for current confinement in III-nitride devices

Jean-François Carlin, Marc Ilegems, Julien Dorsaz, Nicolas Grandjean

Highly selective oxidation of an AlInN interlayer buried in a GaN matrix is demonstrated. This technique was successfully applied to form current apertures in III-nitride light-emitting diodes (LEDs). GaN LEDs were grown by metal-organic vapor phase epitax ...

2005

Progress in AlInN-GaN Bragg reflectors: Application to a microcavity light emitting diode

Jean-François Carlin, Marc Ilegems, Julien Dorsaz

We report on the progress in the growth of highly reflective AlInN-GaN distributed Bragg reflectors deposited by metalorganic vapor phase epitaxy. Al1-xInxN layers with an In content around x similar to 0.17 are lattice-matched to GaN, thus avoiding strain ...

2005

Lattice-matched distributed Bragg reflectors for nitride-based vertical cavity surface emitting lasers

Jean-François Carlin, Marc Ilegems, Julien Dorsaz, Nicolas Grandjean, Raphaël Butté, Eric Feltin

Very narrow spontaneous emission (Deltalambda similar to 0.5 nm), corresponding to a quality factor Q in excess of 800, has been obtained under continuous-wave excitation at room temperature with an AlInN/GaN monolithic microcavity. The structure is made o ...

2005

Characterization of deep levels in n-GaN by combined capacitance transient techniques

Jean-François Carlin, Marc Ilegems, Marcel Py

Deep centers in undoped n-GaN grown by Hydride Vapor Phase Epitaxy were characterized by Deep Level Transient Spectroscopy (DLTS), revealing four known levels with activation energies in the range 0.17-0.94 eV. Deeper levels in the bandgap were observed by ...

Wiley2005

Recent progress in the growth of highly reflective nitride-based distributed Bragg reflectors and their use in microcavities

Jean-François Carlin, Marc Ilegems, Julien Dorsaz, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Gabriel Christmann

The growth of highly-reflective nitride-based distributed Bragg reflectors (DBRs) and their use in vertical cavity structures is reviewed. We discuss the various nitride material systems employed to design Bragg mirrors and microcavities, namely the Al-x(G ...

2005

Midinfrared intersubband absorption in lattice-matched AlInN/GaN multiple quantum wells

Jean-François Carlin, Marc Ilegems, Nicolas Grandjean, Raphaël Butté, Eric Feltin, Sylvain Nicolay, Mauro Mosca

We report the observation of midinfrared intersubband (ISB) absorption in nearly lattice-matched AlInN/GaN multiple-quantum-wells. A clear absorption peak is observed around 3 mu m involving transitions from the conduction band ground state to the first ex ...

2005

Crack-free fully epitaxial nitride microcavity using highly reflective AllnN/GaN Bragg mirrors

Jean-François Carlin, Marc Ilegems, Julien Dorsaz, Nicolas Grandjean, Raphaël Butté, Eric Feltin

We report the growth over 2 in. sapphire substrates of crack-free fully epitaxial nitride-based microcavities using two highly reflective lattice-matched AlInN/GaN distributed Bragg reflectors (DBRs). The optical cavity is formed by an empty 3lambda/2 GaN ...

2005

Application of Teflon-AF thin films for bio-patterning of neural cell adhesion

Patrick Aebischer, Marc Ilegems

Teflon AF, an amorphous copolymer of polytetrafluoroethylene (PTFE) with 2,2-bis(triflouromethyl)-4,5-difluoro-1, 3-dioxole, has been receiving widespread attention in the opto-electronics industries and elsewhere for its superior optical and dielectric pr ...

1998