Raman spectroscopy study of graphene thin films synthesized from solid precursor

In this work, we present Raman spectroscopy study of graphene thin films obtained by rapid thermal annealing in vacuum. As a carbon source, we used spectroscopic graphite electrodes cut into small pieces on top of which we deposited copper/nickel thin films. Samples were then annealed at different annealing temperatures (600, 700, 800 and 900 degrees C) for 30 min. Raman spectroscopy study showed that annealing at lower annealing temperatures (600 and 700 degrees C) leads to formation of single layer graphene thin films with relatively high level of defects. Annealing at higher annealing temperatures (800 and 900 degrees C), on the other hand, resulted in formation of homogenous multilayer graphene thin films. From Raman spectra, we also concluded that samples annealed at higher annealing temperatures had lower level of defects compared to the samples annealed at lower annealing temperatures