Publications by Nicolas Grandjean

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Owing to their wide direct bandgap tenability, III-nitride (III-N) compound semiconductors have been proven instrumental in the development of blue light-emitting diodes that led to the so-called solid-state lighting revolution and blue laser diodes that a ...

We report on time-resolved photoluminescence measurements carried out along the thickness gradient of two types of GaN/AlGaN quantum wells with low Al content in the barriers (5% and 9%, respectively). A reduction of the biexciton binding energy with incre ...

GaN films epitaxially-grown on M-sapphire may have different orientations, either nonpolar and semipolar. In this paper, the different epitaxial relationships are investigated in details thanks to transmission electron microscopy. It is shown that these re ...

We report on the low-temperature growth of heavily Si-doped (>10(20) cm(-3)) n(+)-type GaN by N-rich ammonia molecular beam epitaxy (MBE) with very low bulk resistivity (

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 ...

The insertion of an InGaN underlayer (UL) is known to strongly improve the performance of InGaN/GaN quantum well (QW) based blue light emitting diodes (LEDs). However, the actual physical mechanism responsible for it is still unclear. We thus conduct a sys ...

The origin of efficiency droop in state-of-the-art quality In GaN/GaN and GaN/AlGaN quantum wells (QWs) grown on various crystal planes is studied by means of time-resolved photoluminescence spectroscopy associated with a precise determination of the QW ca ...

Nonintentionally doped 200-nm-thick In0.16Al0.84N/n(+)-GaN samples were grown by metal-organic vapor phase epitaxy and used for the electrical characterization of InAlN. In the temperature range 180-400 K, the forward current of Schottky diodes is dominate ...

Making use of bound states in the continuum, we present experimental results on efficient second harmonic generation in photonic crystal cavities supporting doubly-resonant modes. The second harmonic emission is a vortex beam with radial polarization and e ...

The pressure-induced changes in the electronic band structures of In-containing nitride alloys, InxGa1-xN and InxAl1-xN are examined experimentally as well as by ab initio calculations. It is found that the band gap pressure coefficients, dE(g)/dp, exhibit ...

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 ...

We report a study of self-assembled GaN/AlN quantum dots (QDs) grown by metalorganic vapor phase epitaxy. We have investigated the impact of the AlN template quality on the nucleation of QDs obtained by the so-called Stranski-Krastanov growth mode transiti ...

Al2O3 thin films were deposited by a metal organic chemical vapour deposition on InAIN/GaN heterostructures using Ar or NH3 as a carrier gas. Effects of NH3 and Ar carrier gases on the electrical and structural properties of Al2O3/InAIN/GaN HEMT devices we ...

We propose to use lattice-matched AlInN/GaN to replace the Al(Ga)N/GaN material system for III-nitride Bragg reflectors, despite the poor material quality of AlInN reported until very recently. We report an improvement of AlInN material that allowed for su ...

We demonstrate a standard-free method to retrieve compositional information in AlxIn1-xN thin films by measuring the bulk plasmon energy (E-p), employing electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope (STEM). Two se ...

The current-voltage characteristics of the Ni/InAlN/GaN Schottky diodes were measured at various temperatures in the range of 300-700 K. The experimental data were analyzed considering different current-transport mechanisms. From the analysis it follows th ...

We present a comprehensive study of the anisotropic optical properties of nonpolar GaN/AlGaN multiple quantum wells intentionally designed to act as an active region of a planar microcavity operating in the strong-coupling regime. The strain induced by the ...

The microstructure of GaN(Si)/AlInN multiple quantum wells grown on GaN/Al2O3 (0001) templates by metalorganic vapor-phase epitaxy has been investigated using transmission electron microscopy and associated techniques. Dodecagon-shape V-defects with hexago ...

GaN/AlGaN and InGaN/GaN quantum wells (QWs) are investigated as the active region for room-temperature strong exciton-photon coupling in high-quality AlInN/(Al)GaN microcavities (MCs). Angular resolved photoluminescence (PL) measurements performed on an Al ...

Atomic layer deposition (ALD) is supplied to grow ZrO2 high-k gate dielectrics and fabricate InAlN/GaN metal oxide semiconductor (MOS) high electron mobility transistors (HEMTs). Ex situ chemical surface cleaning and optimised in situ InAlN surface pre-tre ...

Nicolas Grandjean

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III-nitride photonic cavities

Impact of quantum confinement and quantum confined Stark effect on biexciton binding energy in GaN/AlGaN quantum wells

Study of the epitaxial relationships between III-nitrides and M-plane sapphire

n(+)-GaN grown by ammonia molecular beam epitaxy: Application to regrown contacts

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

Burying non-radiative defects in InGaN underlayer to increase InGaN/GaN quantum well efficiency

Enhancement of Auger recombination induced by carrier localization in InGaN/GaN quantum wells

Shallow donor and deep DX-like center in InAlN layers nearly lattice-matched to GaN

Efficient second harmonic generation in a doubly resonant photonic crystal cavity based on a bound state in the continuum

Anomalous composition dependence of the band gap pressure coefficients in In-containing nitride semiconductors

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

Strain relaxation of AlN epilayers Stranski-Krastanov GaN/AlN quantum dots grown by organic vapor phase epitaxy

InAIN/GaN metal-oxide-semiconductor high electron mobility transistor with Al2O3 insulating films grown by metal organic chemical vapor deposition using Ar and NH3 carrier gases

Progresses in III-nitride distributed Bragg reflectors and microcavities using AlInN/GaN materials

Standard-free composition measurements of AlxIn1-xN by low-loss electron energy loss spectroscopy

Current transport and barrier height evaluation in Ni/InAlN/GaN Schottky diodes

Tailoring the light-matter coupling in anisotropic microcavities: Redistribution of oscillator strength in strained m-plane GaN/AlGaN quantum wells

Observation of dodecagon-shape V-defects in GaN/AlInN multiple quantum wells

Impact of inhomogeneous excitonic broadening on the strong exciton-photon coupling in quantum well nitride microcavities

Current collapse reduction in InAlN/GaN MOS HEMTs by in situ surface pre-treatment and atomic layer deposition of ZrO2 high-k gate dielectrics