Abstract
Nickel-cobalt-boron alloy films were formed by electroless plating from an Ni-Co-B plating bath containing borax as an additive and hydrazinium chloride as reducing agent. The properties of the films thus obtained were investigated by noting the effect of each deposition parameter on composition, deposition rate, throwing power and uniformity. Film deposition rate was observed to increase with an increase in cobalt ion concentration, and with a rise in the temperature and pH of the bath. The boron content of the films increased in proportion to the nickel content in the films, and showed a higher value the lower the cobalt ion concentration and pH of the bath. X-ray diffraction analysis showed that the crystal structure of the Ni-Co-B alloy films exhibited a diffraction peak on a higher orientation plane of {220} that was not found in deposits from plating baths of nickel or cobalt alone. The throwing power and uniformity of these alloy films were satisfactory.
