A numerical simulation tool for Schottky-Barrier
Carbon Nanotube Field-Effect Transistors (SB-CNFETs), based
on self-consistent solution of Poisson and continuity equations
was developed. Method of moments is used for solving Poisson
equation. Continuity equations are solved using current
boundary conditions. Boundary currents are those currents
tunneling through Schottky barriers at the contacts, which are
calculated numerically using transfer matrix method. Regarding
long devices, we have exploited the fact that, except near the
contacts, the potential on most of the channel length is slowly
varying to reduce the computational burden. During the solution
of Poisson equation, mapping this part of the device into much
smaller length has no perceptible effect on the accuracy of
solution; however, it saves much of the simulation time and
memory and allows the calculation of transport characteristics
inaccessible to classical techniques. |
