3nm GAA Technology featuring Multi-Bridge-Channel FET for Low Power and High Performance Applications

As the most feasible solution beyond FinFET technology, a gate-all-around Multi-Bridge-Channel MOSFET (MBCFET) technology is successfully demonstrated including a fully working high density SRAM. MBCFETs are fabricated using 90% or more of FinFET processes with only a few revised masks, allowing easy migration from FinFET process. Not only on-target but also multiple Vt is achieved in challengingly limited vertical spacing between channels. Also, reliability of MBCFETs is shown to be comparable to that of FinFETs. Three representative superior characteristics of MBCFET compared to FinFET have been demonstrated — better gate control with 65 mV/dec sub-threshold swing (SS) at short gate length, higher DC performance with a larger effective channel width (Weff) at reference footprint, and design flexibility with variable nanosheet (NS) widths. The optimization of the standard cell design by using variable NS width is evaluated. The usefulness of MBCFET as a multi-purpose performance provider is proven by the modulation of effective capacitance (Ceff), effective resistance (Reff) and frequency by Weff control. Finally, mass production feasibility with MBCFET is proven through a fully working high density SRAM circuit.