Figure 6. SERS spectra obtained from assembled 4-ATP molecules on plasmonic nanovoid structures (coated with a 60 nm Ag layer) having different sizes and depths (A) and SERS intensity changes of the 1075 cm⁻¹ peak depending on the diameter of the nanovoids (B), and SERS spectra obtained from self-assembled 4-ATP molecules on plasmonic nanovoid structures (coated with a 5 nm Cr and a 60 nm Ag layer) having different sizes (C).

The excitation wavelength is 633 nm.