SERS performance of GaN/Ag substrates fabricated by Ag coating of GaN platforms

Magdalena A Zając; Bogusław Budner; Malwina Liszewska; Bartosz Bartosewicz; Łukasz Gutowski; Jan L Weyher; Bartłomiej J Jankiewicz

doi:10.3762/bjnano.14.46

SERS performance of GaN/Ag substrates fabricated by Ag coating of GaN platforms

Beilstein J Nanotechnol. 2023 May 3:14:552-564. doi: 10.3762/bjnano.14.46. eCollection 2023.

Authors

Magdalena A Zając^#^{1

2}, Bogusław Budner^#³, Malwina Liszewska³, Bartosz Bartosewicz³, Łukasz Gutowski³, Jan L Weyher¹, Bartłomiej J Jankiewicz³

Affiliations

¹ Institute of High-Pressure Physics, Polish Academy of Sciences, Sokołowska 29/37, 01-142 Warsaw, Poland.
² Faculty of Advanced Technologies and Chemistry, Military University of Technology, gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland.
³ Institute of Optoelectronics, Military University of Technology, gen. Sylwestra Kaliskiego 2, 00-908 Warsaw, Poland.

^# Contributed equally.

Abstract

The results of comparative studies on the fabrication and characterization of GaN/Ag substrates using pulsed laser deposition (PLD) and magnetron sputtering (MS) and their evaluation as potential substrates for surface-enhanced Raman spectroscopy (SERS) are reported. Ag layers of comparable thicknesses were deposited using PLD and MS on nanostructured GaN platforms. All fabricated SERS substrates were examined regarding their optical properties using UV-vis spectroscopy and regarding their morphology using scanning electron microscopy. SERS properties of the fabricated GaN/Ag substrates were evaluated by measuring SERS spectra of 4-mercaptobenzoic acid molecules adsorbed on them. For all PLD-made GaN/Ag substrates, the estimated enhancement factors were higher than for MS-made substrates with a comparable thickness of the Ag layer. In the best case, the PLD-made GaN/Ag substrate exhibited an approximately 4.4 times higher enhancement factor than the best MS-made substrate.

Keywords: GaN/Ag; SERS substrates; magnetron sputtering; nanofabrication; pulsed laser deposition; surface-enhanced Raman spectroscopy (SERS).

Grants and funding

This work was financially supported by MUT Internal Grant no 22-721 and by the Polish Ministry of Defense under research grant no. GBMON/13-993/2018/WAT. M.L. has obtained funding from the ETIUDA 7 PhD scholarship from the Polish National Science Centre (2019/32/T/ST7/00336).