Pulse-reverse electrodeposition of Cu for the fabrication of metal interconnection: II. Enhancement of Cu superfilling and leveling

Superfilling and the leveling of Cu electrodeposition have relevance to the adsorption of organic additives and the changes in their surface coverage. In Part I of this study, it is observed that pulse-reverse electrodeposition changes the surface coverage of PEG-Cl^- and SPS, by the anodic step. This implies that the performances of superfilling, as well as leveling, can be affected by pulse-reverse electrodeposition. In this research, the influences of pulse-reverse electrodeposition on both superfilling and leveling are investigated, with various conditions of anodic step. It is confirmed that pulse-reverse electrodeposition can improve superfilling, as well as leveling performance, compared to conventional constant potential deposition. The results are explained based on the electrochemical analyses introduced in Part I of this study.