Publications de Nicolas Grandjean

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We report a systematic study of the photoluminescence (PL) properties of a series of nearly lattice-matched (LM) GaN/(Al,In)N single quantum well (SQW) samples, with well thickness ranging from 1.5 to 5 nm, grown by metalorganic vapor phase epitaxy. Temper ...

We report on III-nitride based blue vertical cavity surface emitting lasers using defect-free highly reflective AlInN/GaN distributed Bragg reflectors grown on c-plane free-standing GaN substrates. Lasing is demonstrated at room temperature under pulsed el ...

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 ...

Fluoride plasma treatment similar to that used in AlGaN/GaN HEMTs has been applied to InAlN/GaN HEMTs. Enhancement mode of operation is obtained with a pinch-off voltage shifted by 3 V. Owing to the fluoride treatment an increase of the forward gate thresh ...

The capacitance-voltage-temperature characteristics of nonintentionally doped In0.16Al0.84 N/n+- GaN Schottky diodes were measured at 1 MHz and in the 90–400 K range. They are discussed in the framework of existing theories, which properly treat the Poiss ...

The pronounced optical in-plane anisotropy of a suitably designed nonpolar GaN-based microcavity, mainly inherited from the valence-band complexity of wurtzite semiconductors, allows the coexistence of two different light-matter coupling regimes along orth ...

We report on the current properties of Al1-x InxN (x approximate to 0.18) layers lattice- matched ( LM) to GaN and their specific use to realize nearly strain- free structures for photonic and electronic applications. Following a literature survey of the g ...

We observe a room-temperature low-threshold transition to a coherent polariton state in bulk GaN microcavities in the strong-coupling regime. Nonresonant pulsed optical pumping produces rapid thermalization and yields a clear emission threshold of 1 mW, co ...

We investigate the dynamics of donor bound excitons (D degrees X-A) at T = 10K around an isolated single edge dislocation in homoepitaxial GaN, using a picosecond time-resolved cathodoluminescence (TR-CL) setup with high temporal and spatial resolutions. A ...

We study the deep levels in InAlN nearly lattice-matched to GaN by photocapacitance spectroscopy. This technique allows the study of very deep levels having too slow thermal emission rates to be detected by other deep level spectroscopy techniques. We will ...

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 ...

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 ...

Off-axis electron holography is utilized to identify point defect reactions and quantify their dynamics by probing the time and temperature dependence of the Fermi level upon annealing. The methodology is illustrated using implanted carbon (C) in GaN, wher ...

The signature of the strong-coupling regime is unambiguously evidenced in a GaN-based microcavity (MC) above the polariton lasing threshold P-thr at room temperature through the observation of the upper polariton branch. The MC system exhibits a renormaliz ...

We propose a model for leakage currents in Schottky contacts on InAlN/GaN heterostructures based on two distinct tunneling mechanisms. Our modeling relies on structural parameters, in particular, InAlN dielectric constant, interface polarization charges an ...

The mechanisms contributing to experimental quality factors of shortwavelength (lambda = 440-480 nm) III-nitride on silicon one-dimensional photonic crystal cavities were quantified. Fluctuations in fundamental and first-order cavity mode wavelength and qu ...

We report the design and optical characterization of fully suspended wire waveguides and photonic crystal (PhC) membranes fabricated on a gallium nitride layer grown on silicon substrate operating at 1.5 mu m. W1-type PhC waveguides are coupled with suspen ...

We report on the experimental achievement of narrow ultraviolet excitonic and biexcitonic emission from GaN/AlGaN quantum wells. The very large biexciton binding energy (up to 12 meV) inhibits thermalization between the two species allowing to study the re ...

Solar blind detectors have been fabricated based on AlGaN heterostructures grown on sapphire by molecular beam epitaxy or chemical vapour deposition. MSM and Schottky detectors were investigated. High performance devices have been obtained thanks to an opt ...

GaN epilayers are grown on (111) oriented single crystal diamond substrate by ammonia-source molecular beam epitaxy. Each step of the growth is monitored in situ by reflection high energy electron diffraction. It is found that a two-dimensional epitaxial w ...

Nicolas Grandjean

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Optical properties of nearly lattice-matched GaN/(Al,In)N quantum wells

Blue monolithic AlInN-based vertical cavity surface emitting laser diode on free-standing GaN substrate

Visible InGaN/GaN quantum-dot materials and devices

Effect of fluoride plasma treatment on InAlN/GaN HEMTs

Capacitance behavior of InAlN Schottky diodes in presence of large concentrations of shallow and deep states related to oxygen

Nonlinear emission properties of an optically anisotropic GaN-based microcavity

Current status of AlInN layers lattice-matched to GaN for photonics and electronics

Room-temperature polariton lasing in semiconductor microcavities

Exciton dynamics at a single dislocation in GaN probed by picosecond time-resolved cathodoluminescence

Photocapacitance spectroscopy of InAlN nearly lattice-matched to GaN

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

AlGaN/GaN HEMT on (111) single crystalline diamond

Quantifying carbon site switching dynamics in GaN by electron holography

Phase diagram of a polariton laser from cryogenic to room temperature

Leakage mechanisms in InAlN based heterostructures

Quantification of scattering loss of III-nitride photonic crystal cavities in the blue spectral range

Near-infrared characterization of gallium nitride photonic-crystal waveguides and cavities

Biexciton kinetics in GaN quantum wells: Time-resolved and time-integrated photoluminescence measurements

Solar blind detectors based on AlGaN grown on sapphire

GaN grown on (111) single crystal diamond substrate by molecular beam epitaxy