Realization of the complementary doping top-gated graphene filed effect transistor

The complementary doping top-gated graphene field effect transistor (GFET) was fabricated. The neutral polarity of channel doping in the GFET can be converted from n-type to p-type via altering the gate voltage sweeping range. This conversion can be attributed to the charge exchange between graphene and interface trap sites formed in O3 based atomic layer deposition $Al_{2}{O}_{3}$ dielectric layer. The external electric field across the metal/oxide/graphene stack could be tuned by the gate voltage. The charge carriers in channel are stored in trap sites and thus the intrinsic electric property of graphene is changed. This work opens the possibility of complementary p-and n-type top-gated graphene devices for multiple applications.