title: Nanostructured gold films for SERS by block copolymer-templated galvanic displacement reactions.
abstract: Up to now, little effort has been made to exploit large-area high-throughput patterning by block copolymer (BCP) lithography to generate nanostructured substrates with periods well below 100 nm for surface-enhanced Raman scattering (SERS). We show that simple BCP-templated galvanic displacement reactions yield dense arrays of mushroom-shaped gold nanopillars with a period of 50 nm. The nanoporous BCP films used as templates were obtained by swelling-induced reconstruction of reverse micelle monolayers deposited on silicon wafers. Coupling of adjacent mushroom caps almost impinging on each other combined with their strong local curvature results in a high spatial density of hot spots in the narrow gaps between them. Thus, substrates characterized by high SERS efficiencies are obtained.
authors.affiliation: Max Planck Institute of Microstructure Physics, Weinberg 2, D-06120 Halle, Germany. yongwang@njut.edu.cn
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Michael
authors.initials: M
authors.lastname: Becker
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Jinquan
authors.initials: J
authors.lastname: Liu
authors.forename: Roland
authors.initials: R
authors.lastname: Scholz
authors.forename: Juan
authors.initials: J
authors.lastname: Peng
authors.forename: Ulrich
authors.initials: U
authors.lastname: Gösele
authors.forename: Silke
authors.initials: S
authors.lastname: Christiansen
authors.forename: Dong Ha
authors.initials: DH
authors.lastname: Kim
authors.forename: Martin
authors.initials: M
authors.lastname: Steinhart