Raya El Beainou :"Correlation between structure and electrical conductivity in nanostructured W-Cu thin films"

PhD Works of Raya El Beainaou : "Correlation between structure and electrical conductivity in nanostructured W-Cu thin films"

Keywords: Thin films, Electrical Conductivity, Growth, Sputtering, Anisotropy

Abstract : W and W-Cu thin films were deposited by the GLAD co-sputtering technique from two opposite targets: W and Cu. Each target was focused on the center of the substrate with a tilt angle of α = 80 °. Several series were prepared changing some experimental parameters: the sputtering pressure, the film’s thickness as well as the target currents. The nature of as-deposited films and their morphological properties were studied in order to understand the correlations between some structural characteristics and electrical behaviors of these structured films. The experimental parameters play a key-role on the shape of the columns, their angle of inclination, and the elemental composition of these W-Cu films. The influence of these parameters on the films morphology was demonstrated and related to the electronic transport properties in these columnar films. The copper was chemically etched in order to obtain a more porous structure, with the aim of improving the electrical anisotropy. A theoretical model was also developed in order to understand the electrical conductivity mechanism in these columnar films taking into account the anisotropic structure of the columns. This model was applied to W, as-deposited W-Cu and etched W-Cu films.

Evaluation committee:

M. JOUAN Pierre-Yves, Full Professor, University of  Nantes ( Reporter)
M. TRISTANT Pascal, Full Professor, University of Limoges (Reporter)
M. TOMASELLA Eric, Full Professor, University of Clermont Auvergne ( Reviewer)
M. KONSTANTINIDIS Stéphanos, Reserche fellow, University of Mons (Reviewer)
M. PAUMIER Fabien, Assistant Professor, University of Poitiers (Reviewer)
M. PIERSON Jean-François, Full Professor, Université de Lorraine, (Reviewer)
Mme POTIN Valérie, Assistant Professor, University of Bourgogne (PhD Codirector)
M. MARTIN Nicolas,Full Professor, ENSMM (PhD Director)

Localization : Ampithéâtre J-J Gagnepain, Bâtiment TEMIS, 15B, Avenue des Montboucons, Besançon