|
Abstract
|
At this paper afield effect transistor based on graphene nanoribbon (GNR) is modeled. Like in most GNRFETs the GNR is chosen to be semiconductor with a gap, through which the current passes at on state of
the device. The regions at the two ends of GNR are highly n-type doped and play the role of metallic
reservoirs so called source and drain contacts. Two dielectric layers are placed on top and bottom of the
GNR and a metallic gate is located on its top above the channel region. At this paper it is assumed that
the gate length is less than the channel length so that the two ends of the channel region are un-gated.
As a result of this geometry, the two un-gated regions of channel act as quantum barriers between
channel and the contacts. By applying gate voltage, discrete energy levels are generated in channel and
resonant tunneling transport occurs via these levels. By solving the NEGF and 3D Poisson equations self
consistently, we have obtained electron density, potential profile and current. The current variations with
the gate voltage give rise to negative transconductance
|