Large area graphene synthesis on catalytic copper foil by an indigenous electron cyclotron resonance plasma enhanced chemical vapor deposition setup

A novel route for the synthesis of large area graphene by an indigenously built electron cyclotron resonance (ECR) plasma enhanced chemical vapor deposition (PECVD) setup has been reported in this work. A unique 2.45 GHz permanent magnet type ECR PECVD system has been designed and developed for the growth of various nano-structures and films. The apparatus has a unique advantage to synthesize large area graphene at much lower additional substrate heating than heat supplied by an external oven in conventional thermal CVD method. A major amount of heat is supplied here by ECR plasma. Polycrystalline copper foil is used here as a catalytic substrate which is pre annealed inside resonant hydrogen plasma prior to its exposure under precursor gaseous plasma inside the ECR PECVD reactor. Methane is used as carbon precursor along with hydrogen as carrier gas. Argon gas is used for the rapid cooling of the substrate maintaining suitable thermodynamic condition favorable for graphene synthesis. The synthesis process has been carried out by controlling growth temperature, total pressure and synthesis time at various gas ratios. The exposed copper foil has been characterized by Raman spectroscopy to investigate the quality of synthesized graphene in the home made reactor.