Work-Function Variability impact on the performance of Vertically Stacked GAA FETs for sub-7nm Technology Node

Abstract

In this paper, we have reported the impact of gate work function variability on nanosheet field effect transistors (FETs) using 3D TCAD numerical device simulation. We have also studied the WFV using multiple stack channels in NSFETs and NWFETs. The statistical simulation predicts that the MGG induced WFV in NSFETs mainly affects the device threshold voltage (VTH) and on-current (ION). It is estimated that NSFET exhibits better immunity to WFV compared to NWFET for single as well as multiple stacked channels. Therefore, vertically stacked NSFETs are promising to suppress the VTH variation for future technology nodes.