Synergistic Effects of Additives on the Filling Process of High-Aspect-Ratio TSV - Kinetic Monte Carlo Simulation

The effects of additives on the filling process of high-aspect-ratio Through Silicon Via (TSV) have been studied by the kinetic Monte Carlo (KMC) simulation. We included accelerators, suppressors, and levelers in the solution. The synergistic effect of suppressors and levelers is taken into account. We used three kinds of waveforms of the applied current: the pulse current, the pulse reverse current, and the 2-step current (the combination of the pulse current and the pulse reverse current). We confirmed that the dependence of the filling pattern on the leveler concentration corresponds to the experimental results. It is found that the initial distribution of additives plays an important role in the filling. The dependence of filling efficiency on waveforms is also studied. We succeeded in the void-free filling of 12 aspect ratio via(10 mu m X 120 mu m) by using 2-step current.