  Graphene has good mechanical properties including large Young's modulus,
making it ideal for many resonant sensing applications. Nonetheless, the
development of graphene based sensors has been limited due to difficulties in
fabrication, encapsulation, and packaging. Here we report a graphene
nanoresonator based resonant pressure sensor. The graphene nano resonator is
fabricated on a thin silicon diaphragm that deforms due to pressure
differential across it. The deformation-induced strain change results in a
resonance frequency shift of the graphene nano resonator. The pressure sensing
experiments demonstrate a record high responsivity of 20Hz/Pa with a resolution
of 90Pa. The resolution of the sensing scheme is 0.003% of the full-scale range
of the pressure sensor. This exceptional performance is attributed to two
factors: maintaining a high-quality vacuum environment for the nanoresonator
and introducing stimuli through a thin silicon diaphragm. The proposed pressure
sensor design provides flexibility to adjust responsivity and range as needed.
The fabrication method is simple and has the potential to be integrated with
standard CMOS fabrication. The innovative substrate packaging allows the
coupling of the resonator's strain with pressure.
