Monomolecular-Step Polymer Wire Growth from Seed Core Molecules by the Carrier-Gas-Type Molecular Layer Deposition

Using carrier-gas-type molecular layer deposition (CG-MLD), poly-azomethine (AM) wires are grown in monomolecular steps from seed core molecules of amino-alkanethiol self-assembled monolayers by switching molecular gases of terephthalaldehyde and p-phenylenediamine. Fourier transform infrared reflection absorption spectroscopy reveals that the poly-AM wire length linearly increases with the step count of the molecular gas switching until step 12, indicating that monomolecular-step growth of poly-AM wires in upward directions from the seed core molecules is achieved until step 12 (wire length of ∼6 nm). After that, the growth rate decreases, suggesting that some imperfection is induced in the monomolecular-step growth.