Figure 5. (a) SEM Micrographs of 2 nm Ag/17 nm GeO_x/SiO_x/Si(100) @800 °C in air etched with hydro fluoric acid for 90 minutes, (b) SERS spectrum of Crystal Violet with a concentration of 5 × 10⁻¹⁰ Molar drop casted on 2 nm Ag/17 nm GeO_x/SiO_x/Si(100) @800 °C in air etched with HF for 90 min, and (c) SERS spectrum of Crystal Violet of above sample at different points showing the consistency of the substrate with uniform enhancement.