Novel graphene bridge for NEMS based devices

In this paper we presented a method novel that enables formation of free-standing graphene channels and flexures between self-aligned copper electrodes. The method uses 30 nm Cu as the graphene catalyst. The Cu was patterned and under-etched after the graphene growth to free the graphene in selected regions. The graphene growth is carried out at 900°C in C₂H₂ and hydrogen carrier gas at 5 mTorr. This process grows 0.5-5 nm thick graphene layer on copper as determined with micro-Raman peaks and AFM images. Large graphene regions up to the size of 100 μm × 50 μm were grown on Cu electrodes. In another approach, the graphene covered-Cu was patterned followed by copper under etch to produce free-standing graphene bridges supported under a thin layer of photoresist. The free-standing graphene bridges can be used in a variety of devices ranging from graphene transistors to NEMS switches.