Surface‐enhanced Raman scattering sensing on black silicon. Issue 12 (17th June 2013)

• Record Type: Journal Article
• Authors: Gervinskas, Gediminas; Seniutinas, Gediminas; Hartley, Jennifer S.; Kandasamy, Sasikaran; Stoddart, Paul R.; Fahim, Narges F.; Juodkazis, Saulius
• Is Part Of: Annalen der Physik. Volume 525:Issue 12(2013:Dec.)
• Page Start: 907
• Page End: 914
• Publication Date: 2013-06-17
• Subjects: Physics -- Periodicals; Chemistry -- Periodicals; 530.05
• DOI: 10.1002/andp.201300035
• Languages: English
• ISSNs: 0003-3804

Abstract

<abstract abstract-type="graphical" xml:lang="en" id="andp201300035-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Reactive ion etching was used to fabricate black‐Si over the entire surface area of 4‐inch Si wafers. After 20 min of the plasma treatment, surface reflection well below 2% was achieved over the 300–1000 nm spectral range. The spikes of the black‐Si substrates were coated by gold, resulting in an island film for surface‐enhanced Raman scattering (SERS) sensing. A detection limit of 1 × 10⁻⁶ M (at count rate &gt; 10² s⁻¹ . mW⁻¹) was achieved for rhodamine 6G in aqueous solution when drop cast onto a ∼ 100‐nm‐thick Au coating. The sensitivity increases for thicker coatings. A mixed mobile‐on‐immobile platform for SERS sensing is introduced by using dog‐bone Au nanoparticles on the Au/black‐Si substrate. The SERS intensity shows a non‐linear dependence on the solid angle (numerical aperture of excitation/collection optics) for a thick gold coating that exhibits a 10 times higher enhancement. This shows promise for augmented sensitivity in SERS applications. <boxed-text content-type="graphic" position="anchor" orientation="portrait"><graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pgg3z7c8b12" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /></boxed-text></p> </abstract>