Electroless plating of Ni thin films using foam of electrolyte

Electroless plating of Ni thin films was achieved in foam of electroplating solution in place of electroplating liquid. Commercial hypophosphite-based solution for Ni electroless plating was added with a surfactant of sulfuric acid monododecyl ester sodium salt (SDS) and bubbled with nitrogen gas to produce airy foam. Ni thin films were deposited by immersing iron substrates in the foam. Although stationary foam was inconvenient for electrodeposition by itself, film growth was enhanced by generating a flow of foam using substrate rotation and by adding SDS to a concentration of 0.1 to 0.3 wt %. No defects attributed to pinholes were observed on the film surface. This method was effective in reducing the net amount of plating solution necessary for film deposition. (C) 2016 The Japan Society of Applied Physics