title: Controlled oxidation, biofunctionalization, and patterning of alkyl monolayers on silicon and silicon nitride surfaces using plasma treatment.
abstract: A new method is presented for the fast and reproducible functionalization of silicon and silicon nitride surfaces coated with covalently attached alkyl monolayers. After formation of a methyl-terminated 1-hexadecyl monolayer on H-terminated Si(100) and Si(111) surfaces, short plasma treatments (1-3 s) are sufficient to create oxidized functionalities without damaging the underlying oxide-free silicon. The new functional groups can, e.g., be derivatized using the reaction of surface aldehyde groups with primary amines to form imine bonds. In this way, plasma-treated monolayers on silicon or silicon nitride surfaces were successfully coated with nanoparticles, or proteins such as avidin. In addition, we demonstrate the possibility of micropatterning, using a soft contact mask during the plasma treatment. Using water contact angle measurements, ellipsometry, XPS, IRRAS, AFM, and reflectometry, proof of principle is demonstrated of a yet unexplored way to form patterned alkyl monolayers on oxide-free silicon surfaces.
authors.affiliation: Laboratory of Organic Chemistry, Wageningen University, Dreijenplein 8, 6703 HB Wageningen, The Netherlands.
authors.forename: Michel
authors.initials: M
authors.lastname: Rosso
authors.forename: Marcel
authors.initials: M
authors.lastname: Giesbers
authors.forename: Karin
authors.initials: K
authors.lastname: Schroën
authors.forename: Han
authors.initials: H
authors.lastname: Zuilhof
mesh_terms: D001360:Avidin / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D008962:Models, Theoretical; D053758:Nanoparticles / Q000737:chemistry; D010084:Oxidation-Reduction; D056951:Photoelectron Spectroscopy; D010949:Plasma / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D017655:Silicon Compounds / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D020099:Coated Materials, Biocompatible; D017655:Silicon Compounds; D001360:Avidin; C032734:silicon nitride; D012825:Silicon