Spectral and structural investigation of layered growth of copper and graphene deposited by sputtering and annealing

Various processes such as mechanical exfoliation, thermal decomposition of SiC, epitaxial layers, arc discharge, and chemical vapour deposition have been used to grow monolayer and multilayer graphene. However, the film qualities vary from batch to batch, thickness control is poor and quite often is non-environment friendly. Physical vapour deposition is an environmentally friendly process, but very few reports are there on graphene growth by this process. In the present manuscript, the layered growth of Cu and C of different thicknesses was deposited by magnetron sputtering and the growth mechanism of graphene for as-deposited as well for annealed films is studied. The a-C layer of thickness 20nm yielded graphene of the best quality with 2-3 layers and I-2D/I-G ratio of 1.23.