Tunneling Field-Effect Transistors (TFETs) are one of the potential candidates as device building blocks beyond conventional planer bulk-CMOS.  In this project, 2D numerical simulations will be carried out to characterize the cylindrical nanowire TFETs in terms of structural variations (wire radius, gate length, oxide thickness), material variations (gate and dielectric materials, body materials and doping), and source/drain engineering (doping profile, Schottky-barrier, and dopant segregation).  Such numerical investigations will provide guidance to TFET device design and optimization.  The results will also be useful for validating analytical models as well as comparison with experimental data.