Coordination-compounds As Precursors for Laser Deposition of Nickel-based Conducting Films

Devillers, Michel [UCL] Dupuis, O. Janosi, A. Soumillion, Jean-Philippe [UCL]

Coordination compounds of nickel(II) are used as precursors for the formation of nickel and nickel oxide deposits on alumina substrates by direct laser writing using an argon ion laser. The starting resins are made of aqueous, methanolic or N,N-dimethylformamide (dmf) solutions of nickel(II) acetate, formate or acetylacetonate in the presence of a polymeric cellulose-based additive which controls the spin-coating step of the substrate. Infrared, UV-visible and NMR spectroscopic studies are carried out on the acetate solutions and resins to understand the interactions occurring between the various components. Arguments supporting the replacement of water molecules in tetrahydrated nickel(II) acetate by the organic solvent are described. The nature of the obtained deposits is determined by X-ray photoelectron spectroscopy. Whereas resins based on acetate or acetylacetonate compounds in dmf and methanol are shown to generate nickel oxide films, aqueous resins based on nickel(II) formate are found to be very promising in view of obtaining conductive deposits of nickel metal. The role of the cellulosic additive is clearly restricted to the viscosity modulation.