Performance of AlGaSb/InAs TFETs With Gate Electric Field and Tunneling Direction Aligned

The current-voltage characteristics of AlGaSb/InAs staggered-gap n-channel tunnel field-effect transistors are simulated in a geometry in which the gate electric field is oriented to be in the same direction as the tunnel junction internal field. It is shown that this geometry can also support low-voltage operation and low subthreshold swing. In the absence of a simple analytic theory for this transistor to allow direct analytic comparisons, two-dimensional numerical simulations are used to explore the electrostatic and geometrical design considerations including dependence on gate length, gate underlap, gate undercut, and equivalent oxide thickness.