During the electroplating process and under particular condition, a thin gel layer forms on the cathode surface. This layer is called a barrier layer and it retards the more noble metal in electrolyte. The work presented in the paper traces the effective technique of improving diffusion of the noblest metal ions through this barrier layer by means of ultrasonic waves. Ultrasound was used to produce micro-edges, which transport an electrolyte at the wafer surface. A high-frequency single element was used to produce electrolyte oscillations. Schlichting streaming theory basically describes those micro-edges. The experiments were done for Ni-Fe plating bath based on J. Horkans. The results indicate that by controlling the acoustic intensity, it is possible to change the angular velocity of edges and thus to control the amount of liquid injected to the vicinity of a cathode. In this way, apart from simple ion diffusion, the controlled migration inside barrier layer can be accomplished and thus the inspecting of the mass of more noble metal in the plated alloy is possible.
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