Effects of Ar plasma and Ar fast atom bombardment (FAB) treatments on Cu/polymer hybrid surface for wafer bonding

Cu/polymer hybrid surface was treated by Ar plasma and Ar fast atom bombardment to confirm the feasibility of Cu/polymer hybrid bonding by using surface activated bonding method. Uncross-linked novolac resin mixed with imidazole as the curing agent was used as the polymer adhesive. We used X-ray photoelectron spectroscopy to study the effects of Ar plasma and Ar FAB treatments on the Cu/polymer surface. It was shown that Ar FAB could remove Cu native oxides on Cu surface efficiently rather than Ar plasma. Cu contamination on polymer surface was present after surface treatment, which is due to Cu ion adsorption on polymer surface during the Cu/polymer hybrid surface treating process.