Nanostructured gold films for SERS by block copolymer-templated galvanic displacement reactions.
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.
Wang
Yong
Y
Max Planck Institute of Microstructure Physics, Weinberg 2, D-06120 Halle, Germany. yongwang@njut.edu.cn
Becker
Michael
M
Wang
Li
L
Liu
Jinquan
J
Scholz
Roland
R
Peng
Juan
J
Gösele
Ulrich
U
Christiansen
Silke
S
Kim
Dong Ha
DH
Steinhart
Martin
M