Modelling of Surfactant Mass Balance for Microvia Fill Monitoring

The mass balance of surface-adsorbing additives in a microvia filling bath is modeled. The model considers the additives´ mass balance between both the solution and the surface-adsorbed layer of additives, as well as on a shape-changing cathode surface, where mass balance of the additives is affected by the surface shape changes. The model is implemented as a finite element model, which applies the arbitrary Lagrange-Eulerian method for tracking the cathode surface shape changes. Further, a weak formulation of the mass balance equations is created in order to enable numerical solution of the model. The model is compared against experiment results.