The device characteristics of asymmetric Schottky Tunneling Source Transistor (STSFET) is investigated through a TCAD modeling study. This work aims to improve the drive current and also to reduce the leakage current. One advantage of this device is that the drive current can be improved by controlling the schottky barrier heights through gate voltage variations. Depending upon the applications, the designer can select proper silicides. Schottky Tunneling Source FET is a promising device alternative for future nanometer scale technology since it improves the scalability and offers large power reduction in mixed signal applications. Silicon devices give better drive current than germanium devices. The off current is limited by the tunneling from the drain region. The asymmetric Schottky Tunneling Source FET offers high immunity to short channel effects. The asymmetric nature of the device helps to reduce the leakage current and it also help to improve the linear characteristics of the device by reducing ambipolar conduction through the use of a pocket drain at the drain end.