title: Directed self-assembly of solvent-vapor-induced non-bulk block copolymer morphologies on nanopatterned substrates.
abstract: We report a study on directed self-assembly (DSA) with solvent annealing to induce the formation of non-bulk block copolymer microdomains on chemical patterns. Ultrathin films of symmetric polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) display morphologies of PMMA dots, stripes, and PS hexagons with increasing exposure time to acetone vapor, a PMMA-selective solvent. All three nanostructures form long-range-ordered and registered arrays on striped chemical patterns with periods (LS) commensurate to the solvated PS-b-PMMA microdomain period (L0,s). Solvent annealing is shown to facilitate DSA on non-regular chemical patterns, on which the local periods are incommensurate to L0,s. DSA with feature density multiplication, via solvent annealing, is also demonstrated.
authors.affiliation: HGST, a Western Digital Company, San Jose Research Center, 3403 Yerba Buena Rd., San Jose, CA 95135, USA.
authors.forename: Lei
authors.initials: L
authors.lastname: Wan
authors.affiliation: Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Science, 5625 Renmin Street, Changchun, 130022 China.
authors.forename: Shengxiang
authors.initials: S
authors.lastname: Ji
authors.affiliation: IBM Albany NanoTech, 257 Fuller Road, Albany, NY 12203, USA.
authors.forename: Chi-Chun
authors.initials: CC
authors.lastname: Liu
authors.affiliation: Institute for Molecular Engineering, University of Chicago, 5747 South Ellis Avenue, Chicago, IL 60637, USA. nealey@uchicago.edu.
authors.forename: Gordon S W
authors.initials: GS
authors.lastname: Craig
authors.affiliation: Institute for Molecular Engineering, University of Chicago, 5747 South Ellis Avenue, Chicago, IL 60637, USA. nealey@uchicago.edu.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Nealey