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Jean-François Carlin

Cette personne a quitté l’EPFL

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Publications associées (180)

Page 4 sur 9

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

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

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

Investigation and modeling of the role of interface defects in the optical degradation of InGaN/GaN LEDs

Nicolas Grandjean, Jean-François Carlin, Camille Haller

We investigate the degradation mechanisms of In0.2Ga0.8N/GaN light emitting diodes through combined experimental analysis and simulations. The devices were submitted to constant current stress at 100 mA. Depending on the measuring current level, two degrad ...

2024

Emission characteristics of GaN-based blue lasers including a lattice matched Al0.83In0.17N optical blocking layer for improved optical beam quality

Nicolas Grandjean, Jean-François Carlin, Eric Feltin, Julien Dorsaz, Antonino Francesco Castiglia, Gatien Cosendey

We demonstrate room-temperature continuous-wave operation of 425 nm InGaN-based blue laser diodes including a thin Al0.83In0.17N optical blocking layer. Structures are grown on c-plane GaN freestanding substrates with a lattice-matched AlInN layer position ...

AIP American Institute of Physics2010

AlInN/GaN a suitable HEMT device for extremely high power high frequency applications

Nicolas Grandjean, Jean-François Carlin, Eric Feltin

AlInN/GaN unpassivated High Electron Mobility Transistor (HEMT) on Sapphire substrate has yielded a maximum drain current density close to 2 A/mm in steady state. Superior gate length downscaling than AlGaN/GaN devices has been observed owing to the possib ...

Ieee2007

GaN buffer growth temperature and efficiency of InGaN/GaN quantum wells: The critical role of nitrogen vacancies at the GaN surface

Nicolas Grandjean, Jean-François Carlin, Wei Liu, Yao Chen

An indium-containing layer positioned underneath the InGaN/GaN quantum well (QW) active region is commonly used in high efficiency blue light-emitting diodes. Recent studies proposed that the role of this underlayer is to trap surface defects (SDs), which, ...

AIP Publishing2021

Short cavity InGaN-based laser diodes with cavity length below 300 mu m

Hua Zhang, Nicolas Grandjean, Jean-François Carlin, Raphaël Butté, Denis Martin, Hezhi Zhang

We report on a practical method for developing InGaN-based edge emitting laser diodes of cavity length down to 45 mu m. Samples consisting of one uncoated cleaved facet and one etched facet coated with a high-reflectivity (HR) dielectric distributed Bragg ...

2019

Technology and performance of InAlN/AlN/GaN HEMTs with gate insulation and current collapse suppression using ZrO2 or HfO2

Nicolas Grandjean, Jean-François Carlin, Eric Feltin

We present the technology and performance of InAlN/AlN/GaN MOS HEMTs with gate insulation and surface passivation using ZrO2 or HfO2. About 10-nm-thick high-k dielectrics were deposited by MOCVD before the ohmic contact processing. Plasma pretreatment allo ...

2008

Room-temperature polariton luminescence from a bulk GaN microcavity

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

Low-Noise Microwave Performance of 0.1 mu m Gate AlInN/GaN HEMTs on SiC

Nicolas Grandjean, Jean-François Carlin, Eric Feltin

We report the first microwave noise characterization of AlInN/GaN HEMTs. Transistors with a 0.1 mu m gate implemented on a semi-insulating SiC substrate achieve a maximum current density of 1.92 A/mm at V-GS = 0 V, a measured transconductance g(M) = 480 mS ...

2010

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

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

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

Blue lasing at room temperature in an optically pumped lattice-matched AlInN/GaN VCSEL structure

Nicolas Grandjean, Jean-François Carlin, Eric Feltin, Raphaël Butté, Gabriel Christmann, Julien Dorsaz, Antonino Francesco Castiglia

Laser action with low threshold average pump power density (similar to 50 W. cm(-2)) at room temperature is reported for a crack-free planar vertical cavity surface emitting laser (VCSEL) structure based on a bottom lattice-matched AllnN/GaN distributed Br ...

2007

GaN surface as the source of non-radiative defects in InGaN/GaN quantum wells

Nicolas Grandjean, Jean-François Carlin, Raphaël Butté, Denis Martin, Wei Liu, Gwénolé Jean Jacopin, Camille Haller

Blue light-emitting diodes based on III-nitride semiconductors are nowadays widely used for solid-state lighting. They exhibit impressive figures of merit like an internal quantum efficiency close to 100%. This value is intriguing when considering the high ...

2018

Recombination coefficients of GaN-based laser diodes

Nicolas Grandjean, Jean-François Carlin, Julien Dorsaz, Luca Alex Milo Sulmoni

We measure the charge carrier recombination coefficients of InGaN quantum wells by analyzing the dynamical properties of (Al,In)GaN laser diodes emitting in the violet spectral range. Relaxation oscillations and turn-on delays are fitted to a rate equation ...

2011

Origin of giant enhancement of phase contrast in electron holography of modulation-doped n-type GaN

Nicolas Grandjean, Jean-François Carlin, Raphaël Butté

The electron optical phase contrast probed by electron holography at n-n+ GaN doping steps is found to exhibit a giant enhancement, in sharp contrast to the always smaller than expected phase contrast reported for p-n junctions. We unravel the physical ori ...

2024

Far-field coupling in nanobeam photonic crystal cavities

Nicolas Grandjean, Jean-François Carlin, Raphaël Butté, Ian Michael Rousseau

We optimized the far-field emission pattern of one-dimensional photonic crystal nanobeams by modulating the nanobeam width, forming a sidewall Bragg cross-grating far-field coupler. By setting the period of the cross-grating to twice the photonic crystal p ...

Amer Inst Physics2016

High electron mobility lattice-matched AlInN/GaN field-effect transistor heterostructures

Nicolas Grandjean, Jean-François Carlin, Eric Feltin, Marcel Py

Room temperature electron mobility of 1170 cm(2)/V s is obtained in an undoped, lattice-matched, Al0.82In0.18N/GaN field-effect transistor heterostructure, while keeping a high (2.6 +/- 0.3)x10(13) cm(-2) electron gas density intrinsic to the Al0.82In0.18N ...

2006

Suppression of leakage currents in GaN-based LEDs induced by reactive-ion etching damages

Nicolas Grandjean, Jean-François Carlin, Eric Feltin, Julien Dorsaz, Antonino Francesco Castiglia

Forward and reverse leakage currents in GaN/InGaN multi-quantum well light-emitting diodes (LEDs) are caused by reactive-ion etching (RIE) damages during device patterning. A method to recover the damaged surfaces, based on a chemical etch in KOH: ethylene ...

EDP Sciences2008

High spatial resolution picosecond cathodoluminescence of InGaN quantum wells

Nicolas Grandjean, Benoît Marie Joseph Deveaud, Jean-François Carlin, Jean-Daniel Ganière, Eric Feltin, Andrea Crottini

The authors have studied InxGa1-xN/GaN (x approximate to 15%) quantum wells (QWs) using atomic force microscopy (AFM) and picosecond time resolved cathodoluminescence (pTRCL) measurements. They observed a contrast inversion between monochromatic CL maps co ...

American Institute of Physics2006

Defect incorporation in In-containing layers and quantum wells: experimental analysis via deep level profiling and optical spectroscopy

Nicolas Grandjean, Jean-François Carlin, Camille Haller

Recent studies demonstrated that the performance of InGaN/GaN quantum well (QW) light emitting diodes (LEDs) can be significantly improved through the insertion of an InGaN underlayer (UL). The current working hypothesis is that the presence of the UL redu ...

IOP PUBLISHING LTD2021

Impact of saturation on the polariton renormalization in III-nitride based planar microcavities

Nicolas Grandjean, Jean-François Carlin, Eric Feltin, Raphaël Butté, Jacques Levrat, Georg Rossbach

It has been widely observed that an increasing carrier density in a strongly coupled semiconductor microcavity (MC) alters the dispersion of cavity polaritons, below and above the condensation threshold. The interacting nature of cavity polaritons stems fr ...

Amer Physical Soc2013