In this work, Zinc oxide (ZnO) thin films were deposited on silicon and glass substrates using spin-coating method with different concentrations of precursor (zinc acetate dihydrate) and stabilizer (monoethanolamine). The concentrations of zinc acetate dihydrate and monoethanolamine in isopropanol were varied from 6 mM to 500 mM. Subsequently, the substrate with ZnO thin film as a seed layer was used to grow ZnO nanostructures by hydrothermal process with the same concentration of precursor (zinc nitrate hexahydrate), temperature, and time for each growth. The samples were characterized by field-emission scanning electron microscopy (FESEM), X-rays diffractometer (XRD), and UV-visible spectrophotometer (UV-vis) to study morphology, crystallographic structure, and optical property, respectively. The results showed that particle size, crystallinity, and transmittance of seed layers were changed with increasing concentrations of spin-coated precursor. Furthermore, the nanostructures were found that higher precursor concentration of seed layers affected the formation of ZnO nanorods to be nanosheets.

Silver nanorods, prepared on Si substrates by sputtering deposition with the technique glancing-angle deposition (GLAD), were used as surface-enhanced Raman scattering (SERS) substrates. The prepared samples were categorized into two groups based on sealing conditions after the nanorod fabrications. The non-sealed SERS substrates were prepared by purging in the vacuum chamber with argon, oxygen, and ambient air. The sealed SERS substrates were enveloped with several types of packages, i.e., petri dishes, plastic bags, and foils, where they were all handled in a controlled glove box. The samples were characterized by field-emission scanning electron microscopy (FESEM) for the physical morphologies. The samples were further investigated by Raman spectroscopy for Raman spectra of blank substrates of each condition. The results showed that, in case of the non-sealed category, the SERS substrates purged under the argon gas was best optimized to prevent ambient contamination during prolonged period of time. In the case of the sealed category by different packages, the SERS substrates demonstrated the enhancement of the Raman-shift spectra with very small unwanted peaks, and in addition the extended lifetime.