Self-assembled InAs quantum dots grown on InP (3 1 1)B substrates: Role of buffer layer and amount of InAs deposited

International audienceThe formation of InAs quantum dots by Stransky–Krastanow method on (3 1 1)B InP substrates has been studied. On Al0.48In0.52As alloy lattice matched on InP, large changes of the quantum dot structural characteristics have been observed as a function of the amount of InAs deposited and of the arsenic pressure during the InAs quantum dot formation. Small quantum dots (minimum diameter=20 nm) in very high density (1.3×1011 quantum dots per cm2) have been achieved in optimized growth conditions. These results are interpreted from the strong strain field interaction through the substrate at high density and from the InAs surface energy evolutions with the Arsenic pressure. The effect on quantum dot characteristics of the arsenic pressure during the growth of Al0.48In0.52As buffer layers has also been investigated. Despite the importance of this parameter on the Al0.48In0.52As clustering, weak changes have been observed

DIFFUSION DIFFUSE ET PHASONS DANS LES PHASES ICOSAEDRIQUES ET ICOSAEDRIQUES MODULEES AL-PD-MN

GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

Double capping of molecular beam epitaxy grown InAs/InP quantum dots studied by cross-sectional scanning tunneling microscopy

International audienc

Caractérisation de couches minces de ZnS et design de guides d'ondes en ZnS pour la photonique non linéaire

International audienceCet article présente les atouts sulfure de zinc (ZnS) pour la photonique non linéaire au travers de caractérisations structurelles et optiques de couches minces de ZnS déposées par pulvérisation cathodique. Le design de guide d'onde de ZnS et une première méthode de réalisation par gravure sèche sont également discutés

Effect of a lattice-matched GaAsSb capping layer on the structural properties of InAs/InGaAs/InP quantum dots

International audienceThe influence of a lattice-matched GaAsSb capping layer on the structural properties of self-assembled InAs quantum dots (QDs) grown on InP substrates is studied on the atomic scale by cross-sectional scanning tunneling microscopy. While lattice-matched In0.53Ga0.47As-capped QDs are clearly truncated pyramids, GaAs0.51Sb0.49-capped QDs grown under the same conditions look like full pyramids and exhibit a larger height, indicating that capping with GaAsSb reduces dot decomposition. Since there are no differences in strain between the two capping layers, this behavior is most likely related to the surfactant effect of Sb, which stabilizes the growth front and avoids adatom migration

Computer-aided hepatic tumour ablation

Surgical resection of hepatic tumours is not always possible. Alternative techniques consist in locally using chemical or physical agents to destroy the tumour and this may be performed percutaneously. It requires a precise localisation of the tumour placement during ablation. Computer-assisted surgery tools may be used in conjunction to these new ablation techniques to improve the therapeutic efficiency whilst benefiting from minimal invasiveness. This communication introduces the principles of a system for computer-assisted hepatic tumour ablation

Substrate bonding using electroplated copper through silicon vias for VCSEL fabrication

ISBN: 978-1-4799-5729-3International audienceWe present a novel approach to bound any substrate on a silicon host platform, in the particular case of the realization of InP based vertical cavity surface emitting lasers (VCSEL). This process is based on a mechanical bonding, using electroplated copper through silicon vias. It enables a cost effective bonding with a low induced stress, and a significant improvement of the device thermal properties. Preliminary results are presented on the realization of light emitting diodes