More accurate and reliable extraction of tunneling resistance in tunneling FET and verification in small-signal circuit operation

Abstract

In this paper, a novel method of extracting tunneling resistance from a tunneling FET (TFET) is proposed and verified by small-signal analysis based on radio-frequency (RF) data. Unlike the approaches made in the small-signal equivalent circuits of conventional MOSFETs, the on -state total channel resistance can be separately analyzed into tunneling and inversion layer resistances. In this paper, an RF method is suggested and proven to be more practical and realistic since it calls for neither a set of complicated measurements with a number of geometric splits of devices under test nor device simulations with imaginary material parameters to identify the tunneling resistance of a TFET device as usually employed in DC methods. To verify the extracted tunneling resistances, their dependences on gate length and bias conditions have been investigated in silicon nanowire TFETs. Furthermore, related small-signal parameters are analyzed with the highlight of the relation between tunneling resistance and inversion layer length. It is confirmed by Y -parameters that models with extracted tunneling resistances are valid in the RF domain and under various geometric and operation conditions up to 300 GHz.