Extending the Variety of Applications in Micro Electroplating by Using the Dog Bone Effect

This study explores the development of advanced anode electrodes for electroplating, leveraging the ‘dog-bone effect’ to optimize the deposition process for in homogeneously coated metal surfaces. The research primarily focuses on nickel, silver, and gold substrates, using specially shaped platinum anodes. Anode designs are based on electrochemical simulations via COMSOL Multiphysics, with special emphasis on the dog-bone effect to achieve different layer thicknesses. The uniquely shaped anodes enable controlled current density distributions, resulting in a coating pattern that reflects the anode’s geometry on the substrate. Prototypes of these anodes were produced and tested in a custom electroplating setup, allowing precise deposition on substrates. Key parameters like electrode current, voltage, distance, bath temperature, and circulation were meticulously controlled and optimized. Experimental outcomes affirmed simulation predictions, indicating that the shaped anodes impart a distinct coating characteristic to the substrate. The coatings were analyzed using techniques such as optical interferometry and X-ray fluorescence spectroscopy, confirming the varied layer thicknesses of the metals deposited. This research marks significant progress in anode design for electroplating processes, particularly in controlling the electrolytic coating process via the dog-bone effect. We demonstrate the advantage of prior design and simulations to improve process predictability, performance, and efficiency. This work stimulates further micro plating research and could advance high-performance coatings and innovative applications.