Glancing angle deposited gold nanohelix arrays on smooth glass as three-dimensional SERS substrates

Abstract

Gold nanohelix arrays (NHAs) were fabricated on a smooth glass substrate using glancing angle deposition technique. At a deposition angle of 89°, gold NHAs were fabricated by introducing liquid nitrogen to flow under the backside of BK7 glass substrate holder to reduce the temperature of substrate to be around −140 °C under deposition. The spin rate was controlled with respect to the deposition rate to grow three different sized nanohelices. The morphology and optical properties were measured and compared for the three samples. In application, the surface-enhanced Raman scattering (SERS) from each three-dimensional NHA was measured and analyzed with near field simulation.