Raman spectra of Co3O4 and ZnO thin layers on Si

The Raman spectra were recorded on samples consisting of a zinc oxide (ZnO) layer, a cobalt oxide (Co3O4) layer, and a silicon (Si) substrate. The thickness of the layers is as follows: 70 nm, 15 nm, and 200 µm. The sample was annealed at 400°C for 30 minutes. The Raman measurements were conducted using a T64000 Horiba Jobin-Yvon spectrometer at room temperature, operating in a single subtractive operation mode with an entrance slit width of 0.1 mm. For excitation, the 514.5 nm line of an Ar+ laser was utilized. Detection was performed using a silicon CCD camera cooled with liquid nitrogen.