Molecular-nanolayer-induced suppression of in-plane Cu transport at Cu-silica interfaces

Recent reports have shown that molecular nanolayers (MNLs) can be used to inhibit Cu diffusion across Cu-dielectric interfaces in nanodevice wiring. Here, we demonstrate that MNLs can curtail in-plane interfacial Cu transport. Cu lines embedded in SiO2 in interdigitated comb configurations were passivated by organosilane MNLs with thiol, amino-phenyl, and amino-propyl termini. Leakage current and breakdown voltage measurements at 0-1.4 MV/cm electric fields reveal that amino-phenyl-terminated MNLs are the most effective in inhibiting in-plane leakage, likely due to Cu-N complex formation. Our results suggest that MNLs with appropriate termini could be used to tailor the stability and reliability of device wiring structures. (c) 2007 American Institute of Physics.