Modeling of the Electroplating of a Through‐Hole Considering Additive Effects and Convection

In this paper a general mathematical model of electroplating of high aspect ratio through-holes of multilayer printed circuit boards is developed. This two-dimensional model includes transport by electrical migration, diffusion, and convection in the through-hole. The solution of the model is used to examine the effects of plating variables on uniformity in an acid copper plating bath with and without additives in the bath. Different regimes of plating conditions are examined with particular emphasis on ohmic control. The general model is used to determine the necessary conditions to achieve ohmic-limited plating. These criteria and the solution of the ohmic-limited model used determine the type of flow enhancement required to achieve ohmic-limited plating. General guidance for selection of a model for through-hole plating is developed.