title: Poly(cyclohexylethylene)-block-Poly(lactide) Oligomers for Ultrasmall Nanopatterning Using Atomic Layer Deposition.
abstract: Poly(cyclohexylethylene)-block-poly(lactide) (PCHE-PLA) block polymers were synthesized through a combination of anionic polymerization, heterogeneous catalytic hydrogenation and controlled ring-opening polymerization. Ordered thin films of PCHE-PLA with ultrasmall hexagonally packed cylinders oriented perpendicularly to the substrate surface were prepared by spin-coating and subsequent solvent vapor annealing for use in two distinct templating strategies. In one approach, selective hydrolytic degradation of the PLA domains generated nanoporous PCHE templates with an average pore diameter of 5 ± 1 nm corroborated by atomic force microscopy and grazing incidence small-angle X-ray scattering. Alternatively, sequential infiltration synthesis (SIS) was employed to deposit Al2O3 selectively into the PLA domains of PCHE-PLA thin films. A combination of argon ion milling and O2 reactive ion etching (RIE) enabled the replication of the Al2O3 nanoarray from the PCHE-PLA template on diverse substrates including silicon and gold with feature diameters less than 10 nm.
authors.affiliation: Department of Chemistry and ‡Department of Chemical Engineering and Materials Science, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States.
authors.forename: Li
authors.initials: L
authors.lastname: Yao
authors.affiliation: Department of Chemistry and ‡Department of Chemical Engineering and Materials Science, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States.
authors.forename: Luis E
authors.initials: LE
authors.lastname: Oquendo
authors.affiliation: Department of Chemistry and ‡Department of Chemical Engineering and Materials Science, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States.
authors.forename: Morgan W
authors.initials: MW
authors.lastname: Schulze
authors.affiliation: Department of Chemistry and ‡Department of Chemical Engineering and Materials Science, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States.
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Lewis
authors.affiliation: Department of Chemistry and ‡Department of Chemical Engineering and Materials Science, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States.
authors.forename: Wayne L
authors.initials: WL
authors.lastname: Gladfelter
authors.affiliation: Department of Chemistry and ‡Department of Chemical Engineering and Materials Science, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Hillmyer
keywords: atomic layer deposition; block polymer; nanolithography; nanopores; selective infiltration synthesis; self-assembly; solvent vapor annealing