Search results for "Material chemistry"

Fabrication and characterization of barium silicate ultrathin films as an alternative gate oxide

2008

Down-scaling of elementary CMOS elements requires the replacement of SiO2 as a gate oxide. By the identification of the formation conditions of barium silicate in direct contact of a silicon substrate, this study revealed a potential candidate. First of all, a reaction between Ba and SiO2 leading to the formation of barium silicate as been evidenced by in-situ XPS and SR-PES analyses. Then, barium silicate films have been elaborated by oxygen and barium co-deposition at 580 °C. Thermal treatments under vacuum showed that barium silicate was thermally stable up to 900 °C. TEM and SIMS ex-situ analyses revealed a sharp interface with the substrate. Finally, an experimental setup dedicated to …

ARXPS double layers model for in-situ characterization of MOCVD nanometric films.

2006

Communication orale

Gelled Electrolyte Containing Phosphonium Ionic Liquids for Lithium-Ion Batteries

2018

In this work, new gelled electrolytes were prepared based on a mixture containing phosphonium ionic liquid (IL) composed of trihexyl(tetradecyl)phosphonium cation combined with bis(trifluoromethane)sulfonimide [TFSI] counter anions and lithium salt, confined in a host network made from an epoxy prepolymer and amine hardener. We have demonstrated that the addition of electrolyte plays a key role on the kinetics of polymerization but also on the final properties of epoxy networks, especially thermal, thermo-mechanical, transport, and electrochemical properties. Thus, polymer electrolytes with excellent thermal stability (&gt

Etude électrochimique de molécules aminées aliphatiques et hétéroaromatiques. Application aux microcapteurs de pH.

2009

The first part describes the state of the art (electrochemical synthesis, developed applications and electrochemical reaction mechanisms) of the molecules used in his work: pyrrole and ethylenediamine. A second part is dedicated to the evolution of pH measurement processes. Thus, after an explanation of the pH concept, a presentation of both conventional pH measurement technique and of recent pH measurements methods is given.Then, thin polymer films are deposited on platinum surfaces by anodic electropolymerization of pyrrole and ethylenediamine. Then, we tested different electrolyte composition to determine the influence of solvent, salt and monomer concentrations on the electro-oxidation …

Synthesis of Bulk FeAl nanostructured materials by HVOF spray forming and Spark Plasma Sintering

2006

Mid-infrared strong spectral broadening in microstructured tapered chalcogenide AsSe fiber

2012

We report on the generation of a supercontinuum in a chalcogenide microstructured tapered fiber. The suspended core diameter of the fiber is reduced from 5.5 μm to 0.8 μm in the waist of the tapered region. The zero dispersion wavelength is below 2 μm in the tapered region. To pump the fiber, we use a modelocked laser of 4 ps, with a central wavelength of 1960 nm. With only 150 W peak power in the fiber a supercontinuum is generated from 1300 to 2600 nm taking the supercontinuum wavelength edge at -30 dB from the continuum.

High third and second order non linearities of chalcogenide glasses and fibers for compact infrared non linear devices.

2008

Due to their intrinsic nature, chalcogenide glasses present attractive nonlinearities from third and second order, with values reaching between 10 and 1000 times those of silica. We present a study of their properties and their shaping with the purpose to reach efficient devices in the near-mid infrared.

Fabrication and characterization of femtosecond laser induced microstructures in chalcohalide glasses.

2011

International audience

Demonstration of Experimental Infrared Spectral Broadening in Chalcogenide As2S3 Suspended Core Microstructured Optical Fibers

2010

International audience

Infrared non-linear optical properties of low losses As2S3 photonic crystal fibers with different profiles

2010

International audience