Fabrication of Sub-10-nm Plasmonic Gaps for Ultra-Sensitive Raman Spectroscopy


ÇETİN A. E., Yilmaz C., Galarreta B. C., Yilmaz G., Altug H., Busnaina A.

PLASMONICS, cilt.15, sa.4, ss.1165-1171, 2020 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 15 Sayı: 4
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1007/s11468-020-01137-3
  • Dergi Adı: PLASMONICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, INSPEC
  • Sayfa Sayıları: ss.1165-1171
  • Anahtar Kelimeler: Plasmonics, Surface enhanced Raman spectroscopy, Nano-fabrication
  • Dokuz Eylül Üniversitesi Adresli: Hayır

Özet

The past two decades have witnessed the explosion of activities in the field of surface enhanced Raman spectroscopy (SERS). SERS platforms employ nano-structures that excite plasmonic modes with large local electromagnetic fields localized within small gap spaces between each constituting feature. Although the research-oriented SERS platforms yield significant signal enhancements to identify even single molecules, practical SERS-based sensors have not been fully introduced yet. The main reason behind this absence is the need for a cost-effective and reliable manufacturing method for controllable fabrication of plasmonic nano-gaps over large areas. In this article, we introduced a novel manufacturing process that enables fast and scalable fabrication of highly uniform sub-10-nm gaps that could yield large SERS signals. In this process, a conventional electroplating technique is used to produce unique nano-mushroom antenna arrays on a conducting substrate, resulting in controllable gap spaces between mushroom heads. By understanding the nature of mushroom shape antenna formation, we demonstrated the control of inter-metallic gaps down to 5 nm. We showed that the manufactured nano-structures yield Raman enhancements more than 10(8). Providing such large SERS signals that are uniform over large areas, our cost-effective fabrication technique could be very critical to realize practical SERS devices.