Analytical Modelling Of Breakdown Effect In Graphene Nanoribbon Field Effect Transistor (springerbriefs In Applied Sciences And Technology)
by Iraj Sadegh Amiri /
2017 / English / PDF
2.7 MB Download
This book discusses analytical approaches and modeling of the
breakdown voltage (BV) effects on graphene-based transistors. It
presents semi-analytical models for lateral electric field, length
of velocity saturation region (LVSR), ionization coefficient (α),
and breakdown voltage (BV) of single and double-gate graphene
nanoribbon field effect transistors (GNRFETs). The application of
Gauss’s law at drain and source regions is employed in order to
derive surface potential and lateral electric field equations. LVSR
is then calculated as a solution of surface potential at saturation
condition. The ionization coefficient is modelled and calculated by
deriving equations for probability of collisions in ballistic and
drift modes based on the lucky drift theory of ionization. The
threshold energy of ionization is computed using simulation and an
empirical equation is derived semi-analytically. Lastly avalanche
breakdown condition is employed to calculate the lateral BV. On the
basis of this, simple analytical and semi-analytical models are
proposed for the LVSR and BV, which could be used in the design and
optimization of semiconductor devices and sensors. The proposed
equations are used to examine BV at different channel lengths,
supply voltages, oxide thickness, GNR widths, and gate voltages.
Simulation results show that the operating voltage of FETs could be
as low as 0.25 V in order to prevent breakdown. However, after
optimization, it can go as high as 1.5 V. This work is useful for
researchers working in the area of graphene nanoribbon-based
transistors.
This book discusses analytical approaches and modeling of the
breakdown voltage (BV) effects on graphene-based transistors. It
presents semi-analytical models for lateral electric field, length
of velocity saturation region (LVSR), ionization coefficient (α),
and breakdown voltage (BV) of single and double-gate graphene
nanoribbon field effect transistors (GNRFETs). The application of
Gauss’s law at drain and source regions is employed in order to
derive surface potential and lateral electric field equations. LVSR
is then calculated as a solution of surface potential at saturation
condition. The ionization coefficient is modelled and calculated by
deriving equations for probability of collisions in ballistic and
drift modes based on the lucky drift theory of ionization. The
threshold energy of ionization is computed using simulation and an
empirical equation is derived semi-analytically. Lastly avalanche
breakdown condition is employed to calculate the lateral BV. On the
basis of this, simple analytical and semi-analytical models are
proposed for the LVSR and BV, which could be used in the design and
optimization of semiconductor devices and sensors. The proposed
equations are used to examine BV at different channel lengths,
supply voltages, oxide thickness, GNR widths, and gate voltages.
Simulation results show that the operating voltage of FETs could be
as low as 0.25 V in order to prevent breakdown. However, after
optimization, it can go as high as 1.5 V. This work is useful for
researchers working in the area of graphene nanoribbon-based
transistors.