title: Cobalt nanoparticles growth on a block copolymer thin film: a time-resolved GISAXS study.
abstract: Cobalt sputter deposition on a nanostructured polystyrene-block-poly(ethylene oxide), P(S-b-EO), template is followed in real time with grazing incidence small-angle X-ray scattering (GISAXS). The polymer template consists of highly oriented parallel crystalline poly(ethylene oxide) (PEO) domains that are sandwiched between two polystyrene (PS) domains. In-situ GISAXS shows that cobalt atoms selectively decorate the PS domains of the microphase-separated polymer film and then aggregate to form surface metal nanopatterns. The polymer template is acting as a directing agent where cobalt metal nanowires are formed. At high metal load, the characteristic selectivity of the template is lost, and a uniform metal layer forms on the polymer surface. During the early stage of cobalt metal deposition, a highly asymmetric nanoparticles agglomeration is dominating structure formation. The cobalt nanoparticles mobility in combination with the high tendency of the nanoparticles to coalescence and to form immobile large-sized particles at the PS domains are discussed as mechanisms of structure formation.
authors.affiliation: Physik-Department, Lehrstuhl für Funktionelle Materialien, Technische Universität München, James-Franck-Str. 1, 85748 Garching, Germany. ezzmet@ph.tum.de
authors.forename: Ezzeldin
authors.initials: E
authors.lastname: Metwalli
authors.forename: Volker
authors.initials: V
authors.lastname: Körstgens
authors.forename: Kai
authors.initials: K
authors.lastname: Schlage
authors.forename: Robert
authors.initials: R
authors.lastname: Meier
authors.forename: Gunar
authors.initials: G
authors.lastname: Kaune
authors.forename: Adeline
authors.initials: A
authors.lastname: Buffet
authors.forename: Sebastien
authors.initials: S
authors.lastname: Couet
authors.forename: Stephan V
authors.initials: SV
authors.lastname: Roth
authors.forename: Ralf
authors.initials: R
authors.lastname: Röhlsberger
authors.forename: Peter
authors.initials: P
authors.lastname: Müller-Buschbaum
mesh_terms: D003035:Cobalt / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D053838:Scattering, Small Angle; D013997:Time Factors; D014961:X-Ray Diffraction
chemical_list: D003035:Cobalt; D011092:Polyethylene Glycols