Atomistic simulation of gate-all-around GaSb/InAs nanowire TFETs using a fast full-band mode-space NEGF model

Atomistic device simulations are presented to assess the potential of InAs/GaSb GAA NW n- and p-TFETs with diameter d of 5.45 nm. Using a recent breakthrough in atomistic modeling, more than 100× reduction in simulation time was achieved using a tight binding mode-space approach. This enabled full-band transport simulation for a device with ~100,000 atoms, employing an accurate sp
³
s*SO (10 orbitals/atom) tight binding basis. At I
_OFF
of 10 pA/μm, an optimized n-TFET with a pocket region is predicted to have I
_ON
of 46 and 196 μA/μm at V
_DD
of 0.3, and 0.5 V, respectively. This achieves a better energy-delay product than its MOSFET counterpart. Through careful design, similar performance can be achieved for p- and n- TFETs.