Two Dimensional Quantum Mechanical Simulation of Low Dimensional Tunneling Devices

We present a 2-D quantum mechanical simulation framework based on self-consistent solutions of Schroedinger-Poisson system, using the Finite Element Method. The quantum mechanical model includes direct as well as phonon-assisted transitions and it is applied to Germanium electron-hole bilayer tunnel FETs (EHBTFET). It is found that 2D direct tunneling through the underlap regions may degrade the subthreshold characteristic of germanium EHBTFETs and requires careful device optimization to make the tunneling in the overlap region dominate over the parasitic paths.