In-plane and tunneling pressure sensors based on graphene/hexagonal boron nitride heterostructures

An in-plane pressure sensor (IPPS) consisting of graphene sandwiched by hexagonal boron nitride (h-BN) and a tunneling pressure sensor (TPS) consisting of h-BN sandwiched by graphene are demonstrated. The responses as function of external pressure are modeled. The current varies by 3 orders of magnitude as pressure increases from 0 to 5 nN/nm(2). The IPPS current is negatively correlated to pressure, whereas TPS current exhibits positive correlation to pressure. The IPPS design is insensitive to the number of wrapping h-BN layers, indicating precise process control is unnecessary. The result paves a viable avenue towards realizing of atomic scale pressure sensors. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3643899]