Design and simulation of high-k gate all-around structure in SB-GN MOSFET(Ge) using TCAD

Germanium has been considered as an attractive substitute channel material, due to its high carrier mobility and low tunneling mass. The main features of schottky barrier MOSFET are low parasitic resistance, reduced off-state current, and elimination of bipolar action. In this paper, we modeled P-type schottky barrier germanium nanowire (SB-GN) MOSFET using TCAD in 12nm and 40nm technology, replacing both source and drain as metal. The superior property of germanium in SB-GN MOSFET shows, increased on-state current of 120 μA and off-state current of 70 pA in 40nm technology. Also by scaling the transistor sizing to 12nm, we get higher on-state current of 3.33 mA and less off-state current of 17.6 pA. The designed gate all-around structure gives better channel control and greater drive current than conventional germanium based MOSFET (planar). The study shows, the variation in oxide thickness results in increased device performance and better Ion/Ioff ratio in the order of 10⁶. Higher performance, reduced off-state current and increased on-state current in SB-GN MOSFET can be used in memory, high current driven devices, solar controllers etc.