GaSbBi alloys and heterostructures: fabrication and properties

International audienceDilute bismuth (Bi) III-V alloys have recently attracted great attention, due to their properties of band-gap reduction and spin-orbit splitting. The incorporation of Bi into antimonide based III-V semiconductors is very attractive for the development of new optoelectronic devices working in the mid-infrared range (2-5 µm). However, due to its large size, Bi does not readily incorporate into III-V alloys and the epitaxy of III-V dilute bismides is thus very challenging. This book chapter presents the most recent developments in the epitaxy and characterization of GaSbBi alloys and heterostructures

ANNEALING OF HIGH DOSE IMPLANTED GaAs WITH HALOGEN LAMPS

Le recuit de GaAs implanté par un système de deux lampes à halogene est présenté. Le confinement de l'échantillon monté entre une plaque de silicium et une plaque de quartz permet d'obtenir une protection par contact. Cette configuration a permis l'étude par diffusion Raman de la reconstruction du réseau cristallin après irradiation ainsi que la limite de dégradation en surface du substrat par perte d'arsenic.The use of radiation from two halogene lamps to anneal implanted GaAs has been studied. Contact protection of the substrate is obtained by mounting it in a sandwich configuration between a silicon and a quartz plate. This configuration allows to measure by Raman scattering lattice recovery after irradiation and substrate surface degradation due to arsenic loss

Annealing of High Dose Implanted GaAs with Halogen Lamps

ABSTRACTHalogen lamps are used to anneal implanted GaAs. Surface protection is obtained by mouting the substrate in a sandwiched configuration between a silicon and a quartz plate. Raman scattering measurements are carried out to follow simultaneously lattice reconstruction and surface degradation due to Arsenic loss. The evolution of the Raman spectra is compared to a T.E.M. analysis carried out on the same samples.</jats:p

SOFT PHONON VALLEY NEAR THE TRANSITION TO AN INCOMMENSURATE PHASE IN BARIUM SODIUM NIOBATE

The dynamic characteristics of the tetragonal to incommensurate transition in Barium Sodium Niobate has been investigated. The precursor effects consist, in the tetragonal phase, of a soft phonon and a central peak

"Generation of TOA radiative fluxes from the GERB instrument data"part I-Methods

The first Meteosat Second Generation (MSG) satellite has been launched in August 2002. This EUMETSAT's satellite carries 2 new instruments on the geostationary orbit: the Spinning Enhanced Visible and InfraRed Imager (SEVIRI) and the Geostationary Earth Radiation Budget(GERB). The unique feature of GERB in comparison with previous measurements of the Earth's radiation budget (e.g. ERBE, ScaRaB and CERES experiments) is the high temporal sampling afforded by the geostationary orbit, albeit for a limited region of the globe. The GERB instrument provides accurate broadband measurements of the radiant energy due to the reflection of the incoming solar energy by the Earth-atmosphere system and due to the thermal emission within this system. The synergetic use of the SEVIRI data is needed to convert these directional measurements (radiances) into radiative fluxes at the top-of-atmosphere. Additionally, the SEVIRI data allows the enhancement of the spatial resolution of the GERB measurement. The first part of the RMIB contribution describes the near real-time GERB processing system that has been set up at the Royal Meteorological Institute of Belgium (RMIB). This includes the unfiltering of the instrument data, the radiance-to-flux conversions and the spatial resolution enhancement

RAMAN VIBRATIONAL STUDIES OF TRANSIENT ANNEALING OF GaAs AMORPHOUS THIN FILMS

Des couches endommagées par implantation ionique, à forte dose, dans GaAs ont été reconstruites à l'aide d'un laser Ruby pulsé (nsec), d'un laser Nd-YAG pulsé (psec) ou d'un système de lampes à halogène. La reconstruction du réseau cristallin par ces différentes techniques de recuit rapide est étudiée par diffusion Raman des phonons.A nanosecond pulsed ruby laser, a picosecond pulsed Nd-YAG laser and a set of halogen lamps are used to induce the reconstruction of the damage layer obtained by high dose ion implantation in single crystal GaAs. The lattice reconstruction by these different rapid irradiation sources has been examined by Raman scattering from the phonons