Growth of nano-graphene on SrTiO3 (110) substrates by chemical vapour deposition

Abstract

Transfer of graphene from metal catalyst to dielectrics is a complicated procedure which affects the quality of graphene. In the present work, direct growth of graphene was established on strontium titanate (SrTiO3) substrates with the means of chemical vapour deposition (CVD). The graphene growth on catalyst free dielectric substrates were carried out for 3, 4 and 7 h at 1000 °C. Raman spectrum showed D, G and 2D peaks of graphene for the samples. Scanning electron microscope (SEM) was used to get an initial measurement about the morphological structure. Energy Dispersive X-ray spectrometer attached with SEM was also used to get information about the composition of carbon content which showed a considerable increase for the CVD grown sample as compare to bare substrate. Atomic force microscope (AFM) images of the samples surface clearly showed multilayer graphene domains of different sizes and height for different growth time. AFM height profile showed an increase in vertical growth with the increase in growth time. X-ray photoelectron spectroscopy (XPS) was used to get further information about the presence of necessary elements like graphene (carbon), its bonding with STO substrates and the shift in position of fermi level of graphene layers. XPS mapping was also done to get information about the non-uniform growth of carbon surface grown on SrTiO3 surface.