H atom surface loss kinetics in pulsed inductively coupled plasmas

International audiencePulsed plasmas are very powerful tools to investigate mechanisms. This paper is focused on H atom kinetics in low-pressure high-density inductively coupled pulsed plasmas. We explore pure H2, H2/N2, CH4/H2 and CH4/N2 mixtures. These gas mixtures offer two very different kinds of wall conditions, which are stainless-steel and hydrocarbon-coated walls. It shows that H loss probability (β) is sensitive to wall conditions. Efforts are made to understand β evolutions with the different parameters. The effect of pressure in non-depositing plasmas is also investigated. Evolution of H atom surface loss probability is linked to ion flux measurements. Ion bombardment promotes H surface loss

From copper/carbon thin films to nanoporous carbon for sensing applications

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Optimisation technologique de transistors pour le développement de microcapteurs chimiques nano-fonctionnalisés

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a-SiC x N y thin films deposited by a microwave plasma assisted CVD process using a CH 4 /N 2 /Ar/HMDSN mixture: Methane rate effect

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Growth and characterisation of carbon nanostructures obtained by MPACVD system using CH4/CO2 gas mixture

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Structural and optical properties of a-SiCN thin film synthesised in a microwave plasma at constant temperature and different flow of CH4 added to HMDSN/N-2/Ar mixture

International audienceAmorphous SiCN (a-SiCN) thin films were deposited by microwave plasma assisted chemical vapour deposition (MPACVD) using N2, Ar, CH4 and vaporised hexamethyldisilazane (HMDSN) gases. The CH4 ratio (0 to 12%) effect on composition, structural and optical properties of thin layers synthesised at a constant growth temperature of 550^oC has been studied. It was found that layers are mainly composed of silicon nitride like compound and that CH4 addition leads to denser and smoother films. An augmentation of the refractive index from 1.72 to 2.05 and Tauc gap from 4.3 to 4.7eV has also been measured with CH4 ratio increase from 0 to 12%. These results show that CH4 addition to the feed gas allows varying the composition, morphology and the optical properties of HMDSN a-SiCN based films

Isolated acoustic wave based on AlN/ZnO/diamond structure for sensor applications

International audienceWe present a theoretical calculation and experimental results for an isolated acoustic wave. The experimental device is modeled by finite element method (FEM) for the structure AlN/ZnO/diamond. The phase velocity in the AIN/ZnO/diamond structure was investigated by theoretical calculations. It was found that the AlN thickness must he at least more than 3 lambda/2 to obtain a negligible surface displacement. In the same way the ZnO thickness for a fixed value of AlN at 2 lambda must be higher than lambda/4 to confine the acoustic wave. The coupling of the wave presents an optimum around lambda 2 for the ZnO layer thichness