Simulation of through via bottom-up copper plating with accelerator for the filling of TSVs

Filling high aspect ratio through silicon vias(TSVs) without voids and seams by copper plating is one of the technical challenges for 3D integration. Bottom-up copper plating is an effective solution for TSV filling. In this paper, a new numerical model was developed to simulate the electrochemical deposition(ECD) process, and the influence of an accelerator in the electrolyte was investigated. The arbitrary Lagrange-Eulerian(ALE) method for solving moving boundaries in the finite element method(FEM) was used to simulate the electrochemical process. In the model, diffusion coefficient and adsorption coefficient were considered, and then the time-resolved evolution of electroplating profiles was simulated with ion concentration distribution and the electric current density.