Right angle radio frequency magnetron sputtering technique (RAMS) was redesigned to favor the production of high-quality hydroxyapatite (HA) thin coatings for biomedical applications. Stoichiometric HA films with controlled crystallinity, thickness varying from 254 to 540 nm, crystallite mean size of 73 nm, and RMS roughness of 1.7 ± 0.9 nm, were obtained at room temperature by tuning the thermodynamic properties of the plasma sheath energy. The plasma energies were adjusted by using a suitable high magnetic field confinement of 143 mT (1430 G) and a substrate floating potential of 2 V at the substrate-to-magnetron distance of Z = 10 mm and by varying the sputtering geometry, substrate-to-magnetron distance from Z = 5 mm to Z = 18 mm, forwarded RF power and reactive gas pressure. Measurements that were taken with a Langmuir probe showed that the adjusted RAMS geometry generated a plasma with an adequate effective temperature of Teff ≈ 11.8 eV and electron density of 2.0 × 10(15) m(-3) to nucleate nanoclusters and to further crystallize the nanodomains of stoichiometric HA. The deposition mechanism in the RAMS geometry was described by the formation of building units of amorphous calcium phosphate clusters (ACP), the conversion into HA nanodomains and the crystallization of the grain domains with a preferential orientation along the HA [002] direction.

Chemical and electrochemical synthesis techniques have been the principal methods of obtaining polymers in industry and scientific research laboratories. However, during the last two decades, photochemical synthesis, although poorly studied, has been reported to present several advantages, in that it is a fast and cheap technique, and it is not aggressive to the environment. The technique has been applied to the production of some conducting polymers. In this study, semiconducting polymeric blends composed of PT3AA-K-PVDF and PT3MA-PVDF were respectively obtained by photochemical polymerization in aqueous solutions of 3-thiophene acetic acid and 3-thiophene methyl acetate monomers using PVDF microporous matrices and potassium dichromate as catalyst. The percentage of products and by-products incorporated in the host matrix was obtained by gravimetric analysis. The chemical structures of the polymers synthesized were analyzed by FTIR, UV-vis and 1 H NMR. GPC analysis indicated the formation of oligomers composed of 5-6 mers. The morphology of the matrices and polymeric blends was observed by SEM-EDS and their electric behavior evaluated by measures of electric conductivity. The SEM images show the presence of polythiophene in the pores of the PVDF microporous membrane. The thermal properties of the polymers and their blends were evaluated by DSC and TGA. Thermal analysis by DSC demonstrated an increase in melting temperature of the blends, attributed to the confinement of PVDF crystalline phases for the polymer photosynthesized. The results of volumetric conductivity measurements of polymeric blends show an increase in conductivity in the matrices from 10 À15 to 10 À11 S cm À1 .

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