Investigation of competitive adsorption between accelerator and suppressor in TSV copper electroplating

In TSV copper electroplating, the goal is to achieve superfilling deposition. In order to reach the bottom-up in TSV copper electroplating, some additives (accelerator suppressor and leveler) are added into the electroplating bath. To know the relationship between additives in the plating solution is very important. In the present work, by means of linear sweep voltammetry (LSV) and cyclic voltammogram (CV), it is found that there is a competition between the accelerator and the suppressor. At the less negative potential, the accelerator shows a strong adsorption property, and the suppressor plays its role in the relatively more negative potential area, which shows a competitive adsorption relationship between the accelerator and the suppressor during the process of bottom-up filling.