▎ 摘　　要

The optical phase shift by reflection on graphene is measured by interference contrast microscopy. The height profile across graphene layers on 300 nm thick SiO2 on silicon is derived from the phase profile. The complex refractive index and conductivity of graphene layers on silicon with 2 nm thin SiO2 are evaluated from a phase profile, while the height profile of the layers is measured by atomic force microscopy. It is observed that the conductivity measured on thin SiO2 is significantly greater than on thick SiO2. Back scattered electron contrast of graphene layers is correlated to the height of graphene layers. (C) 2013 AIP Publishing LLC.