title: Repeated Solid-state Dewetting of Thin Gold Films for Nanogap-rich Plasmonic Nanoislands.
abstract: This work reports a facile wafer-level fabrication for nanogap-rich gold nanoislands for highly sensitive surface enhanced Raman scattering (SERS) by repeating solid-state thermal dewetting of thin gold film. The method provides enlarged gold nanoislands with small gap spacing, which increase the number of electromagnetic hotspots and thus enhance the extinction intensity as well as the tunability for plasmon resonance wavelength. The plasmonic nanoislands from repeated dewetting substantially increase SERS enhancement factor over one order-of-magnitude higher than those from a single-step dewetting process and they allow ultrasensitive SERS detection of a neurotransmitter with extremely low Raman activity. This simple method provides many opportunities for engineering plasmonics for ultrasensitive detection and highly efficient photon collection.
authors.affiliation: Korea Advanced Institute of Science and Technology (KAIST), Department of Bio and Brain Engineering and KAIST Institute for Optical Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Minhee
authors.initials: M
authors.lastname: Kang
authors.affiliation: Korea Advanced Institute of Science and Technology (KAIST), Department of Bio and Brain Engineering and KAIST Institute for Optical Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Sang-Gil
authors.initials: SG
authors.lastname: Park
authors.affiliation: Korea Advanced Institute of Science and Technology (KAIST), Department of Bio and Brain Engineering and KAIST Institute for Optical Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Ki-Hun
authors.initials: KH
authors.lastname: Jeong