Bottom-up Filling of TSV-Scaled Trenches by Using Step Current Electrodeposition

Abstract

Void-free filling of TSV-scaled trenches is achieved by adding a new leveler with an accelerator and polymeric suppressor. Leveler containing two quaternary ammonium salts allows for the galvanostatic bottom-up filling. In addition, the filling time is reduced by applying the step current comprising a first step to establish a growing surface and a second step to reduce the filling time. The deposition height of the growing surface during the first step critically determines the filling performance. By modulating the step condition, the filling time reduced by 47% compared to the constant current deposition. © The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives 4.0 License (CC BY-NC-ND, http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is not changed in any way and is properly cited. For permission for commercial reuse, please email: oa@electrochem.org. [DOI: 10.1149/2.0061510eel] All rights reserved.