Numerical modeling and experimental verification of through silicon via (TSV) filling in presence of additives

Copper electro-chemical deposition (ECD) of through silicon via (TSV) is a key challenge of 3D integration. This paper presents a numerical modeling of TSV filling concerning the influence of the accelerator and the suppressor. The diffusion-adsorption model was used in the simulation and effects of the additives were incorporated in the model. The boundary conditions were derived from a set of experimental Tafel curves with different concentrations of additives, which provided a quick and accurate way for copper ECD process prediction without complicated surface kinetic parameters fitting. The level set method (LSM) was employed to track the copper and electrolyte interface. The simulation results were in good agreement with the experiments. For a given feature size, the current density for superfilling could be predicted, which provided a guideline for ECD process optimization. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.Engineering, Electrical & ElectronicNanoscience & NanotechnologyOpticsPhysics, AppliedSCI(E)EI2ARTICLEjchen@ime.pku.edu.cn8-1211