Communication—Fast Bottom-Up Filling of High Aspect Ratio Micro Vias Using a Single CTAB Additive

Abstract

In this study, by adding a single additive of Cetyltrimethyl Ammonium Bromide (CTAB) to the electrolyte, the bottom-up filling of micro via (Φ20 μm × 200 μm) was obtained with a fast filling rate. Accordingly, it was found that CTAB has a better diffusion performance and electrodeposition inhibition effect compared to a typical suppressor and leveler. Moreover, the filling results of the micro vias indicated that CTAB can be transported to the deep region of the micro via, successfully limiting the growth of Cu on the sidewall in these regions.