Effect of metal work function on the DC characteristics of an asymmetric MOSFET with Schottky-based source

Abstract

Schottky Source (S) and Drain (D) based MOSFETs have been extensively studied in the past. These devices are tunneling based and show improved short channel effects and reduced contact resistance. In this paper we study the effect of S metal work function (ΦM) on the carrier injection process and its impact on the subthreshold swing and ON-OFF current ratio in an asymmetric n-type MOSFET. We show that by carefully tuning the ΦM, tunneling to thermionic injection transition is possible. Asymmetric MOSFETs also show improved OFF current due to reduced hole injection from the drain contact.