抄録
A sensitizer-activator process or a colloidal Pd/Sn process has been widely employed as the catalyst for electroless Cu plating on non-conductive substrates. The authors investigated Ag nanoparticle suspensions as a Pd-free catalyst for the electroless Cu plating. Ag nanoparticle suspensions were prepared by reducing the Ag+ ions in aqueous solutions using Sn2+ ions. The adsorption properties of the Ag nanoparticles on the glass substrates were evaluated by X-ray photoelectron spectra, atomic force microscopy examinations, and UV-vis adsorption spectra, comparing some cationic polymer electrolytes used for conditioning the substrates. It was confirmed that a large quantity of Ag nanoparticles were adsorbed homogenously onto the substrate conditioned with poly (diallyldimethylammonium) chloride. The catalytic activities for the electroless Cu plating were evaluated by the oxidation rate of HCHO. The Ag-nanoparticle adsorbed substrates showed a catalytic activity as high as that of the conventional colloidal Pd/Sn catalyst. High catalytic activity is attributed to highly dispersive adsorption of the Ag nanoparticles on a large surface area.
