Tunnel Field Effect Transistor With Raised Germanium Source

The performance of a tunnel field effect transistor (TFET) with a raised germanium (Ge) source region is investigated via 2-D device simulation with a tunneling model calibrated to experimental data. The comparison of various Ge-source TFET designs shows that a fully elevated Ge-source design provides for the steepest subthreshold swing and, therefore, the largest on-state drive current for low-voltage operation. Mixed-mode (dc and ac) simulations are used to assess the energy-delay performance. In comparison with a MOSFET, an optimized Ge-source TFET is projected to provide for a lower energy per operation for throughput in the frequency range of up to~1 GHz for sub-0.5-V operation.