The observation of the nucleation and growth of electrolessly plated nickel deposited from different bath pH by TEM and QCM method

The important factors for fabricating thinner and more uniform films by electroless plating were discussed. Two kinds of Ni–P films were electrolessly plated from hypophosphite baths. The number density of the grains was low in the Ni–5.3 wt%P deposits which were plated from the pH 9 bath. As deposition proceeded, the grains grew and merged to form a continuous structure. In case of the Ni–12.6 wt%P deposits, which were plated from the pH 6 bath, the number density of the grains was more than twice that of the Ni–5.3 wt%P deposits. The grains formed a continuous structure, with nucleation governed by the initial deposition. Thus, the transition thickness, i.e., the thickness at which the deposits assumed a continuous structure, was lower in the case of pH 6. The difference was caused by the different autocatalytic activity of the deposits due to the difference in phosphorus content. It was found that the thinner and more uniform nickel films could be electrolessly plated under lower autocatalytic activity.