Selective Electroless Nickel Plating of Particle Arrays on Polyelectrolyte Multilayers

Selective electroless nickel plating was demonstrated at the micron scale on 3-D surface microstructures using a two-step method. The 3-D patterned and functional surface microstructures consisted of microparticles, polyelectrolyte multilayers, and self-assembled monolayers, which were built by microcontact printing and directed self-assemblies of polyelectrolytes and particles. Selectively nickel-plated surfaces were characterized with optical microscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Charged Pd catalyst complexes were first deposited on oppositely charged functional surfaces, and then were reduced to elemental nickel (0) selectively where the Pd complex was deposited on the surface. In this work, it was demonstrated that selective electroless nickel plating on complex 3-D microstructures with submicron resolution could be achieved using a two-step electroless plating method.