Publications by Nicolas Grandjean

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We address degradation aspects of lattice-matched unpassivated InAlN/GaN high-electron-mobility transistors (HEMTs). Stress conditions include an off-state stress, a semi-on stress (with a partially opened channel), and a negative gate bias stress (with so ...

Low phase noise lasers based on the combination of III-V semiconductors and silicon photonics are well established in the near-infrared spectral regime. Recent advances in the development of low-loss silicon nitride-based photonic integrated resonators hav ...

Defects can significantly modify the electro-optical characteristics of InGaN light-emitting diodes (LEDs); however, modeling the impact of defects on the electrical characteristics of LEDs is not straightforward. In this paper, we present an extensive inv ...

Crack-free lattice-matched Al0.85In0.15N/GaN heterostructures were grown on sapphire substrates with barrier thicknesses up to 100 nm which exhibit very high polarization-induced electron sheet density (>2.5 x 10(13) cm(-2)) located at the heterointerface. ...

The growth of InGaN quantum wells ( QWs) by metal-organic vapour phase epitaxy is investigated by atomic force microscopy ( AFM). It is shown that for low growth temperatures the surface morphology of the thin InGaN well layer ( 1.5 nm) exhibits a meanderi ...

Layered halide perovskites (LHPs) are emerging semiconductor materials due to their superior environmental stability compared to that of traditional halide perovskites. While LHPs have tunable optoelectronic properties, quantum and dielectric confinement e ...

Evidence of composition fluctuations around threading dislocations at scales ranging from atomic distances to tens of nanometers is provided by z-contrast imaging, strain measurement, and energy dispersive x-ray spectroscopy in AlxIn1-x N/GaN heterostructu ...

Near-lattice-matched GaN/AlInN multiple quantum wells (MQWs) are investigated by means of the diamond anvil cell high-pressure technique. The hydrostatic pressure dependence of the photoluminescence dE(PL)/dp and the variation in the PL peak energy with th ...

We report on intersubband absorption of near infrared radiation in AlN/GaN superlattice structures grown by metal-organic vapor-phase epitaxy. A good correlation between well thickness and absorption peak energy was obtained. One sample shows a photovoltai ...

We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG) and third harmonic generation (THG) in suspended gallium nitride slab photonic crystal (PhC) cavities on silicon, under continuous-wave resonant excitat ...

Compared to the AlGaN alloy, which can only be grown under tensile strain on GaN, the AlInN alloy is predicted by Vegard's law to be lattice-matched (LM) on fully relaxed GaN templates for an indium content of similar to 17.5%, i.e., it can be grown either ...

Secondary ion mass spectroscopy (SIMS) and capacitance-voltage measurements were combined to thoroughly study Mg doping in GaN layers grown by metal organic vapor phase epitaxy. First we found that the Mg steady-state incorporation regime occurs for a surf ...

By performing pump-probe experiments, we study the relaxation dynamics of spin-polarized excitons in a wurtzite GaN/AlGaN quantum well (QW)grown by metal organic vapor phase epitaxy. The circular degree of polarization of the differential reflectivity sign ...

The Ni/Al2O3/InAlN/AlN/GaN metal-oxide-semiconductor heterostructure (MOS-H) is investigated using capacitance-voltage and capacitance-time characteristics in the temperature range of 25-300 degrees C. An anomalous positive voltage shift of the capacitance ...

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 ...

We report on the achievement of III-nitride blue superluminescent light-emitting diodes on GaN substrates. The epitaxial structure includes an active region made of In0.12Ga0.88N quantum wells in a GaN/AlGaN waveguide. Superluminescence under cw operation ...

We report the first 94-GHz (W-band) large-signal performance of AlInN/GaN high-electron-mobility transistors (HEMTs) grown on high-resistivity silicon (111) substrates. A maximum output power density of 1.35 W/mm and peak power-added-efficiency of 12% are ...

The lattice parameters and strain evolution in Al1-xInxN films with 0.07

We demonstrate state-of-the-art p-type (Al) GaN layers deposited at low temperature (740 degrees C) by ammonia molecular beam epitaxy (NH3-MBE) to be used as top cladding of laser diodes (LDs) with the aim of further reducing the thermal budget on the InGa ...

We report on the properties of III-nitride based microcavities (MCs) operating in the strong coupling regime (SCR) up to room temperature. We first discuss why this class of materials is well suited to investigate the physics of cavity polaritons, which ar ...

Nicolas Grandjean

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Analysis of degradation mechanisms in lattice-matched InAlN/GaN high-electron-mobility transistors

Near ultraviolet photonic integrated lasers based on silicon nitride

Modeling the electrical characteristics of InGaN/GaN LED structures based on experimentally-measured defect characteristics

Temperature mapping of Al0.85In0.15N/AlN/GaN high electron mobility transistors through micro-photoluminescence studies

Growth mode induced carrier localization in InGaN/GaN quantum wells

Decoupling Interlayer Spacing and Cation Dipole on Exciton Binding Energy in Layered Halide Perovskites

Stress-modulated composition in the vicinity of dislocations in nearly lattice matched AlxIn1-x N/GaN heterostructures: A possible explanation of defect insensitivity

Pressure-induced piezoelectric effects in near-lattice-matched GaN/AlInN quantum wells

Near infrared absorption and room temperature photovoltaic response in AlN/GaN superlattices grown by metal-organic vapor-phase epitaxy

Efficient continuous-wave nonlinear frequency conversion in high-Q gallium nitride photonic crystal cavities on silicon

Two-dimensional electron gas density in Al1-xInxN/AlN/GaN heterostructures (0.03

Role of stable and metastable Mg-H complexes in p-type GaN for cw blue laser diodes

Spin relaxation of free excitons in narrow GaN/AlxGa1-xN quantum wells

Thermally induced voltage shift in capacitance-voltage characteristics and its relation to oxide/semiconductor interface states in Ni/Al2O3/InAlN/GaN heterostructures

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

Broadband blue superluminescent light-emitting diodes based on GaN

94-GHz Large-Signal Operation of AlInN/GaN High-Electron-Mobility Transistors on Silicon With Regrown Ohmic Contacts

Effects of strain and composition on the lattice parameters and applicability of Vegard's rule in Al-rich Al1-xInxN films grown on sapphire

Low temperature p-type doping of (Al)GaN layers using ammonia molecular beam epitaxy for InGaN laser diodes

Tailoring the strong coupling regime in III-nitride based microcavities for room temperature polariton laser applications