Effects of amine- and pyridine-terminated molecular nanolayers on adhesion at Cu–SiO2 interfaces

Recent work has shown that molecular nanolayers (MNLs) are attractive candidates for isolating and enhancing adhesion of Cu∕SiO2 interfaces for sub 100nm integrated circuits. Here, we report the effects of solution concentration and SiO2 surface treatment on the adhesion of Cu∕SiO2 interfaces treated with organosilane MNLs with two different nitrogen-containing termini. MNLs from 5mM concentration solution form monolayers and enhance adhesion, while 50mM solutions form multilayers via unregulated self-polymerization, leading to inferior adhesion. Electron spectroscopy of fracture surfaces reveals that the Cu∕MNL interface is the weakest link.