The Insight into Cu-Cu direct bonding of 3DIC

This paper presents study on the manufacturing process of Cu-Cu direct bonding for 3DIC. Main procedures include RCA cleaning, SiO2 film growth, lithography, E-gun deposition, adhesion layer deposition, cleaning and Cu oxide layer removal, dicing, and bonding. Of the two cleaning methods—plasma treatment and acid treatment—employed on wafers, the one with plasma treatment demonstrate superior bonding strength. The study results encompass SEM, pull tests, SAT, and TEM examination results on bonding condition of wafer with both plasma and acid treatment. This research offers insights into optimizing the fabrication process for enhanced performance in Cu-Cu direct bonding for 3DIC applications.