Modeling and simulation of electrodeposition: effect of electrolyte current density and conductivity on electroplating thickness

摘要

Electroplating or electrodeposition is a process carried out in an electrochemical cell where a current is used to form a coating on a metal surface. Developing and optimizing conditions for electroplating is time consuming and modeling and simulation could be used to optimize the electrodeposition process. Electrolyte current density and conductivity are important parameters for an electrodeposition system as they dictate the overall efficiency of flow of ions in the electrolyte system and thus optimization of these parameters is necessary. In this manuscript we report the development of a mathematical model to predict the electrodeposition of copper on cobalt chrome alloy in an electrochemical cell with copper and cobalt chrome alloy as the electrodes and copper sulfate as the electrolyte. The developed model was validated using experiments. The coating thickness of the samples was characterized using scanning electron microscope (SEM) and a thickness gage. At 30 min the model predicted the copper thickness to be 11.7 μm while experimentally the coating thickness was found to be 9.445+/-1.79 (mean +/- SD) using SEM and 12.375+/-1.36 (mean +/- SD) using thickness gauge. When predicting effect of current density the model accurately predicts general trends however the model seems to vary from experimental values in regions where there is significant effect of the electrochemical double layer that the model does not account for. The model accurately predicts the trend of effect of electrolyte conductivity on coating formation. The model can thus be used as a starting point to predict effect of process parameters on electrodeposition thickness.