Publications by Nicolas Grandjean

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The in-plane polarities of GaN and ZnO non-polar films deposited on r- and m-sapphire are compared. The polarity is unique on r-sapphire and mixed on m-sapphire because the direction on the substrate surface parallel to the wurztite c-direction is polar in ...

M-plane GaN epilayers have been directly grown on m-plane sapphire substrates by hydride vapor phase epitaxy using a low temperature GaN nucleation layer. The m-plane GaN surface is optically smooth and mirror-like, with rms roughness similar to 2.0 nm (5 ...

With the aim of increasing the efficiency of green and blue light-emitting diodes, we investigate the luminescence of InGaN/GaN quantum wells on structured GaN buffer layers. ...

Transmission electron microscopy and photoluminescence investigations have been carried out on a series of quantum wells grown by molecular beam epitaxy and metal organic vapour phase epitaxy. In both cases, the emission wavelength and the peak width agree ...

The authors report on the achievement of optically pumped III-V nitride blue microdisk lasers operating at room temperature. Controlled wet chemical etching of an AlInN interlayer lattice matched to GaN allows forming inverted cone pedestals. Whispering ga ...

We observe the buildup of strong (similar to 50%) spontaneous vector polarization in emission from a GaN-based polariton laser excited by short optical pulses at room temperature. The Stokes vector of emitted light changes its orientation randomly from one ...

We present GaN-based high electron mobility transistors (HEMTs) with a 2-nm-thin InAlN/AlN barrier capped with highly doped n(++) GaN. Selective etching of the cap layer results in a well-controllable ultrathin barrier enhancement-mode device with a thresh ...

GaN tunnel junctions (TJs) are grown by ammonia molecular beam epitaxy. High doping levels are achieved with a net acceptor concentration close to similar to 10(20) cm(-3), thanks to the low growth temperature. This allows for the realization of p-n juncti ...

We apply metal organic chemical vapour deposition (MOCVD) of HfO2 and of ZrO2 from beta-diketonate precursors to grow high-k gate dielectrics for InAlN/AlN/GaN metal oxide semiconductor (MOS)-high electron mobility transistors (HEMTs). High-k oxides of abo ...

We report on InAlN/GaN high electron mobility transistors (HEMTs) grown by metal organic vapor phase epitaxy on sapphire with ultrathin buffers. Two dimensional electron gas (2DEG) exhibiting high mobility (1100 cm(2) /V s) and low sheet resistivity (356 O ...

We study the influence of pump current and absorber bias voltage on the pulse width and frequency of sustained pulsation in GaN-based multisection laser diodes. The observed frequencies and pulse widths range from 1.5 to 4.5GHz and 90 to 18 ps, respectivel ...

We grew heavily Mg-doped GaN using ammonia molecular-beam epitaxy. The use of low growth temperature (740 degrees C) allows decreasing the incorporation of donor-like defects (

We report on InGaN edge emitting laser diodes with a top metal electrode located beside the laser ridge. Current spreading over the ridge is achieved via a highly doped n(+)-type GaN layer deposited on top of the structure. The low sheet resistance of the ...

The authors report room temperature polariton lasing at lambda similar to 345 nm in a hybrid AlInN/AlGaN multiple quantum well microcavity (MQW-MC) containing a GaN/AlGaN MQW active region, i.e., the achievement under nonresonant optical excitation of cohe ...

We have studied the properties of Mg-doped GaN epilayers grown by molecular beam epitaxy (MBE) with ammonia as nitrogen source. GaN p-n homojunctions has been developed to determine the optoelectronic characteristics of the junctions as a function of the p ...

The authors report a technique for selective wet chemical etching of an AlInN sacrificial layer lattice-matched to GaN for the fabrication of air-gap photonic structures. It is used to demonstrate high quality factor (Q) microdisk cavities. Whispering gall ...

The authors report on the demonstration of strong light-matter coupling at room temperature using a crack-free UV microcavity containing GaN/AlGaN quantum wells (QWs). Lattice-matched AlInN/AlGaN distributed Bragg reflectors (DBRs) with a maximum peak refl ...

Mg-doped GaN with a net acceptor concentration (NA-ND) in the high 10 19 cm(-3) range was grown using ammonia molecular-beam epitaxy. Electrical properties of NiO contact on this heavily doped p-type GaN were investigated. A potential-barrier height of 0.2 ...

The authors report on strategies to achieve lasing in electrically driven vertical cavity surface emitting lasers at room temperature, namely the improvement of the quality factor of a microcavity suited for electrical injection, the use of a ZnO contact t ...

Nicolas Grandjean

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In-Plane Polarities of Nonpolar Wurtzite Epitaxial Films Deposited on m- and r-plane Sapphire Substrates

M-Plane GaN Grown on m-Plane Sapphire by Hydride Vapor Phase Epitaxy

Modification of InGaN quantum well luminescence by microstructured buffer layers

Investigation of the In composition in InGaN/GaN quantum wells deposited by MOVPE and/or MBE with emission from violet to green

Blue lasing at room temperature in high quality factor GaN/AlInN microdisks with InGaN quantum wells

Spontaneous polarization buildup in a room-temperature polariton laser

Ultrathin InAlN/AlN Barrier HEMT With High Performance in Normally Off Operation

InGaN based micro light emitting diodes featuring a buried GaN tunnel junction

MOCVD of HfO2 and ZrO2 high-k gate dielectrics for InAlN/AlN/GaN MOS-HEMTs

Ultrathin InAlN/GaN heterostructures on sapphire for high on/off current ratio high electron mobility transistors

Self-Pulsation at Zero Absorber Bias in GaN-Based Multisection Laser Diodes

Backward diodes using heavily Mg-doped GaN growth by ammonia molecular-beam epitaxy

InGaN laser diode with metal-free laser ridge using n(+)-GaN contact layers

Room temperature polariton lasing in a GaN/AlGaN multiple quantum well microcavity

High doping level in Mg-doped GaN layers grown at low temperature

LIGHT-EMITTING DIODES Solid-state lighting on glass

High quality nitride based microdisks obtained via selective wet etching of AlInN sacrificial layers

Room temperature polariton luminescence from a GaN/AlGaN quantum well microcavity

Low p-type contact resistance by field-emission tunneling in highly Mg-doped GaN

Towards room temperature electrically pumped blue vertical cavity surface emitting lasers