A method of reducing solder mask interface attack in a process of fabricating printed circuit boards. The method comprises the steps of providing a printed circuit board with a solder mask applied thereon and treating the printed circuit board with an immersion plating solution, wherein the immersion plating solution is plated onto the printed circuit board with the use of ultrasonics in the plating bath. It has been found that the use of ultrasonics at a frequency of about 40 kHz for the entire plating duration provides beneficial results.