  Near-interfacial oxide traps and chemical impurities on the graphene surface
or at the graphene-dielectric interface can be a source of intentional or
unintentional doping of graphene sheet. The efficiency of such chemical doping
can vary in a wide range depending on parameters of graphene field effect
devices. Mechanisms of such sensitivity of doping efficiency to the device
characteristics need to be understood. The objective of this paper is to
theoretically derive the analytical relations, adapted to the explicit
calculation of graphene chemical doping.
