Low-Temperature synthesis of multilayer graphene directly on SiO₂ by current-enhanced solid-phase deposition using Ni catalyst

Low-Temperature deposition of multilayer graphene (MLG) directly on devices without transfer process is a critical issue for the realization of device applications of MLG such as interconnects and electrodes. Low-Temperature synthesis of MLG at around 400 °C is obtained by current-enhanced solid-phase deposition (CE-SPD) using Ni as a catalyst, where current is applied to the C/Ni layer during annealing. MLG crystallinity, which is indicated by G/D ratio in Raman spectra, was improved about four times by applying current, compared to that without current at the same temperature. As the current increases, the G/D ratio is improved. It is considered that current has an effect in enhancing the grain-growth of MLG besides Joule's heat and it leads to lower synthesis temperature.