Copper nanoparticles were fabricated and deposited on a glass substrate by spark discharge of copper electrode under different
atmospheric conditions for SERS application. An interesting dependence of the deposition process and the formation of different
particle structures on the deposition atmospheres were observed. Static air atmosphere ensured the deposition of the Cu
particles on the glass surface by avoiding the repulsion between charged Cu particles and the surface of the glass through the
formation of CuO, which acts as a seed mediated for nanorods formation. The average diameter of the as-deposited Cu rods
was measured by the TEM to be 39 nm. Thermal annealing of the film up to 200 °C resulted in a reduction in the diameter
of the nanorods as well as an increase in the rod density. A water solution of dye molecule (crystal violet) with a concentration
of 1 × 10–6 to 1 × 10–9 M was dropped on the prepared Cu substrate. Raman signals from dye molecule were detected
and their intensities changed according to deposition time, post-annealing temperature and dye concentration. A significant
increase in the Raman scattering signal of a dye molecule was observed in the film fabricated at 30 min of deposition time
and post-annealed temperature of 200 °C for 1 h. This substrate provides a maximum SERS intensity with a detection limit
of 1 × 10–8 M, with an enhancement factor of 3.9 × 103. The SERS performance of the substrates was correlated well with
the change in their surface morphologies.