High-K Metal Gate Fundamental Learning And Multi-V-T Options For Stacked Nanosheet Gate-All-Around Transistor

In this paper, we report multi-threshold-voltage (multi-V-T) options for stacked Nanosheet gate-all-around (GAA) transistors. V-T can be modulated through workfunction metal (WFM) thickness as well as the inter-nanosheet spacing (T-sus), the combination of which may be leveraged to increase the number of undoped V-T offerings within a CMOS device menu relative to a FinFET CMOS device menu, which fundamentally does not have T-sus as a V-T tuning option. Hence we propose our multi-V-T scheme by taking advantage of the unique structure of stacked GAA transistor.