Estimation of electrode contact impedance and conductivity of single-layer graphene using electrical impedance tomography

Abstract

Abstract The paper describes a novel method of detecting defects in the fabrication of graphene films which have many important applications due to their unique mechanical and electronic properties. The illustrative method is based upon electrical impedance tomography and is demonstrated using a testbed to obtain the conductivity profile across the entire graphene surface. Sensed data are processed using a described reconstruction procedure that estimates electrode contact impedances and spatial conductivity. The results are presented of numerical simulations and experiments with graphene wafers of size 2.5 cm. The results show that the proposed method can jointly estimate contact impedance at each electrode and conductivity distribution.