▎ 摘　　要

Deposition of high quality dielectrics onto graphene is of significant challenge because of the chemically inert surface of the two-dimensional carbon lattice which cannot provide nucleating sites for high-kappa oxide insulators. Here we utilize an ultrathin hydroxyl-free organic film, the benzocyclobutene (BCB) polymer, as a buffer layer between graphene and high-x dielectrics in top-gate graphene transistors. By electrical measurements and Raman spectra, it has been demonstrated that the BCB-buffered dielectric stack does not significantly impact the electrical characteristics and doping level of graphene channel, allowing for high carrier mobility to be maintained in top-gate operation. Moreover, the application of the hydroxyl-free buffered dielectrics could remarkably decrease the density of interface state, and then suppress the hysteresis in graphene transistors, which is desirable for high performance graphene electronics. (C) 2015 Elsevier Ltd. All rights reserved.