Thermal properties of two types of porous silicon are studied using the pulsed-photothermal method (PPT). This method is based on a pulsed-laser source in the nanosecond regime. A 1D analytical model is coupled with the PPT technique in order to determinate thermal properties of the studied samples (thermal conductivity and volumetric heat capacity). At rst, a bulk single crystal silicon sample and a titanium thin lm deposited on a single crystal silicon substrate are studied in order to validate the PPT method. Porous silicon samples are elaborated with two dierent techniques, the sintering technique for macroporous silicon and electrochemical etching method for mesoporous silicon. Metallic thin lms are deposited on these two substrates by magnetron sputtering. Finally, the thermal properties of macroporous (30% of porosity and pores diameter between 100 nm and 1000 nm) and mesoporous silicon (30% and 15% of porosity and pores diameter between 5 nm and 10 nm) are determined in this work and it is found that thermal conductivity of macroporous (73 W.m-1 .K-1) and mesoporous (between 80 and 50 W.m-1 .K-1) silicon is two times lower than the single crystal silicon (140 W.m-1 .K-1).

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In the present study, we investigate different surface pretreatments and their influence on a subsequent surface metallization. A direct liquid injection metalorganic CVD (DLI-MOCVD) process is presented for the low temperature metallization of composites, ultimately aiming at the surface functionalization of 3D parts. The process involves the organometallic precursor Cu(I) hexafluoroacetylacetonate 2-methyl-1-hexene-3-yne (hfac)Cu(MHY). We determine chemical kinetics of the global deposition reaction and show the improvement of the adhesion of the Cu films by applying surface pretreatments that etch and/or activate the surface before deposition. To this purpose, gas phase and wet chemical processes are used. Gas phase pretreatments consist either in the use of a remote microwave plasma, an in situ UV oxidation, or in the deposition of acrylic acid/ethylene plasma buffer layer by using an atmospheric pressure cold plasma jet. The liquid phase pretreatment is based on a commercial series of solutions that includes swelling, oxidation, and neutralization steps. The adhesive strength of the Cu films on poly-epoxy and on carbon fiber/poly-epoxy composite surfaces is specifically investigated by scratch and cross-cut testing, and is correlated with topographical, chemical, and energetic characteristics of the surfaces prior deposition, investigated by interferometry, X-ray photoelectron spectroscopy and wettability measurements through the sessile drop method. Pretreatments result in surface functionalization and topographical changes which significantly increase the surface energy and improve the wettability. In some cases the induced modification of the microstructure of the Cu films is found to be beneficial to the electrical resistivity.