Universal analytic model for tunnel FET circuit simulation

A simple analytic model based on the Kane-Sze formula is used to describe the current-voltage characteristics of tunnel field-effect transistors (TFETs). This model captures the unique features of the TFET including the decrease in subthreshold swing with drain current and the superlinear onset of the output characteristic. The model also captures the ambipolar current characteristic at negative gate-source bias and the negative differential resistance for negative drain-source biases. A simple empirical capacitance model is also included to enable circuit simulation. The model has fairly general validity and is not specific to a particular TFET geometry. Good agreement is shown with published atomistic simulations of an InAs double-gate TFET with gate perpendicular to the tunnel junction and with numerical simulations of a broken-gap AlGaSb/InAs TFET with gate in parallel with the tunnel junctio

Tunnel FET device characteristics for RF energy harvesting passive rectifiers

The lack of high power conversion efficiency in RF passive rectifier circuits at sub-µW power levels with current MOSFET technologies is directly related with the difficulty of the transistors in conducting the required level of current at low voltage values. With a different carrier injection mechanism, the superior electrical characteristics of the Tunnel FET devices at low voltage values (sub-0.25 V) can outperform the process of energy conversion at ultra-low power, thus improving the operation range of RF energy harvesting circuits. In this work, a simulation study on the doping profile and material selection of Tunnel FET devices shows the impact of device properties in rectifier circuit efficiency.Postprint (published version