Simulation of copper electroplating fill process with different parameters for through silicon via

Abstract

Copper electrodeposition of through silicon via(TSV) is one of the technical challenges for 3D integration, and parameters that impact on a high aspect ratio TSV filling are various. A numerical model of TSV filling which is based on different parameters is established to simulate the copper plating process in TSV. The flux, current density and shape evolution during copper deposition process are obtained through the numerical model with a commercial software, and the impact on the filling mechanism of three plating parameters- concentration, diffusion coefficient, and electrode potential - have been investigated by comparing the void area of deposition with different parameters. We found that the effects of concentration and diffusion coefficient on TSV filling were similar, and the increasing concentration or diffusion coefficient led to a better filling; the reducing electrode potential is beneficial to fill. Thus a guideline for optimizing the filling of a high aspect ratio TSV was provided.