Jean-François Carlin

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We are progressively approaching the physical limits of microcavity LEDs (MC-LEDs) for high brightness, high efficiency LEDs. They are promising high efficiency devices and they offer the very attractive prospect of full planar fabrication process. However, to compete with other high efficiency LED schemes, they need to approach or surpass the 50 % efficiency mark. We first explore the limits of planar MC-LEDs in both the GaAllnAsP and GaInAlN materials systems, and show that the single-step extraction limi

We have investigated an inductively coupled plasma etching recipe using SiCl4 and SF6 with a resulting selectivity >10 for GaN in respect to InAlN. The formation of an etch-resistant layer of AlF3 on InAlN required about 1 min and was noticed by a 4-times- ...

III-nitride membranes offer promising perspectives and improved device designs in photonics, electronics, and optomechanics. However, the removal of the growth substrate often leads to a rough membrane surface, which increases scattering losses in optical ...

The electrical properties and deep trap spectra were compared for near-UV GaN/InGaN quantum well (QW) structures grown on free-standing GaN substrates. The structures differed by the presence or absence of a thin (110 nm) InGaN layer inserted between the h ...

We report a numerical and experimental investigation of fabrication tolerances and outcoupling in optically pumped III-nitride nanolasers operating near lambda = 460 nm, in which feedback is provided by a one-dimensional photonic crystal nanobeam cavity an ...

We measure the modal absorption coefficient of the InGaN quantum wells (QWs) in the absorber section of (Al,In)GaN multisection laser diodes as a function of bias voltage and photon energy using optical gain-spectroscopy. In the examined laser diodes, the ...

IIIV photonics on silicon is an active and promising research area. Here, we demonstrate room-temperature (RT) lasing in short-wavelength III-nitride photonic crystal nanobeam cavities grown on silicon featuring a single InGaN quantum well (QW). In the low ...

III-N optoelectronic devices are of great interest for many applications. Visible emitters (based on InGaN) are widely used in the lighting, display and automotive fields. Ultraviolet LEDs (based on AlGaN) are expected to be widely used for disinfection, m ...

The crossover from an exciton gas to an electron-hole plasma is studied in a GaN/(Al,Ga)N single quantum well by means of combined time-resolved and continuous-wave photoluminescence measurements. The two-dimensional Mott transition is found to be of continuous type and to be accompanied by a characteristic modification of the quantum well emission spectrum. Beyond the critical density, the latter is strongly influenced by band-gap renormalization and Fermi filling of continuum states. Owing to the large bi

We investigate the density of defects and the degradation rate in InGaN light-emitting diodes having identical dislocation density and epitaxial structure, but different indium content in the quantum well (QW; 12%, 16%, 20%). Our results, based on combined ...

A 3 lambda/2 (In,Ga)N/GaN resonant cavity, designed for similar to 415nm operation, is grown by molecular beam epitaxy and is sandwiched between a 39.5-period (In,Al)N/GaN distributed Bragg reflector (DBR), grown on c-plane GaN-on-sapphire pseudo-substrate ...

We discuss the characteristics of In0.17Al0.83N/GaN high-electron mobility transistors with barrier thicknesses between 33 and 3 nm, which are grown on sapphire substrates by metal-organic chemical vapor deposition. The maximum drain current (at V-G = +2.0 ...

When a growth interruption is applied to the top interface of a nominally 3 monolayers (ML) thick InAs quantum well (QW), grown on an InP substrate, the InAs layer relaxes by formation of three-dimensional (3D) islands. The emission from the QW is split into at least 8 peaks. Each peak corresponds to an integral number of MLs of InAs. Using cathodoluminescence imaging and photoluminescence excitation spectroscopy, we demonstrate that the emission originates in 3D islands with a lateral extension of less tha

We report on the reliability of GaN-based super-luminescent light emitting diodes (SLEDs) emitting at a wavelength of 405 nm. We show that the Mg doping level in the p-type layers has an impact on both the device electro-optical characteristics and their r ...

We have studied the capabilities of chemical beam epitaxy (CBE) to produce high-gain media for long-wavelength (1.5 mu m) vertical cavity surface emitting lasers (VCSELs). Using a parameter pair of low growth temperature and small V/III ratio the integration of up to 15 highly strained (1.78%) InAsP quantum wells (QWs) into a periodic gain structure (PGS) is successfully demonstrated. In this work we present data of atomic force microscopy (AFM), X-ray diffraction, reflectivity and electro-luminescence meas

A comparison of devices with different source-drain gaps has been performed on AlInN/GaN high electron mobility transistors (HEMTs) grown on SiC. The cut-off frequency is effectively improved through shrinking source drain space and reducing gate parasitic ...

In this study, we investigate the impact of two-dimensional MoS2 coating on the optical properties of surface GaN/AlGaN quantum wells (QWs). A strong enhancement in GaN QW light emission is observed with monolayer-MoS2 coating, yielding luminescence intens ...

Deep defects have a fundamental role in determining the electro-optical characteristics and in the efficiency of InGaN light-emitting diodes (LEDs). However, modeling their effect on the electrical characteristics of the LED is not straightforward. ...

In this work the technology and characterization of nanocrystalline diamond (NCD) films directly grown on InAlN/GaN HEMTs is presented. Optimization of GaN based HEMT process steps including metallization stacks is discussed. A fully processed InAlN/GaN HE ...

We study the impact of non-radiative defects on Auger recombination in c-plane InGaN/GaN single quantum wells (SQWs) in the efficiency droop regime using high injection time-resolved photoluminescence. The defect density in the SQW is controlled by tuning ...

Jean-François Carlin

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Recent results and latest views on microcavity LEDs

Characterization of Plasma-Induced Damage of Selectively Recessed GaN/InAlN/AlN/GaN Heterostructures Using SiCl4 and SF6

Smooth GaN membranes by polarization-assisted electrochemical etching

Deep traps in InGaN/GaN single quantum well structures grown with and without InGaN underlayers

Fabrication defects and grating couplers in III-nitride photonic crystal nanobeam lasers (Conference Presentation)

Bias-dependent absorption coefficient of the absorber section in GaN-based multisection laser diodes

Continuous Wave Blue Lasing in III-Nitride Nanobeam Cavity on Silicon

III-N Optoelectronic Devices: Understanding the Physics of Electro-Optical Degradation

High-temperature Mott transition in wide-band-gap semiconductor quantum wells

Effects of quantum-well indium content on deep defects and reliability of InGaN/GaN light-emitting diodes with under layer

Q-factor of (In,Ga)N containing III-nitride microcavity grown by multiple deposition techniques

Barrier-layer scaling of InAlN/GaN HEMTs

Cathodoluminescence investigations of three-dimensional island formation in quantum wells

GaN-based superluminescent diodes with long lifetime

InAsP/InGaAsP Periodic Gain Structure for 1.5µm Vertical Cavity Surface Emitting Laser Applications

High-speed and low-noise AlInN/GaN HEMTs on SiC

GaN Surface Passivation by MoS2 Coating

Deep defects in InGaN LEDs: modeling the impact on the electrical characteristics

Diamond overgrown InAlN/GaN HEMT

Impact of defects on Auger recombination in c-plane InGaN/GaN single quantum well in the efficiency droop regime