A Novel SiGe Nanosheet Transistor With Channel Release Stopping Layer Structure for Process Variations Suppression and Circuit Performance Improvement

In this study, SiGe channel nanosheet field-effect transistor (NSFET) with a novel channel release stopping layer (CRSL), namely CRSL-SiGe NSFET, is proposed to addresses the issue of sub-fin recess during channel release in conventional SiGe (C-SiGe) NSFET. Through a three-dimensional technology computer-aided design (TCAD) simulations, we systematically compare the DC and AC electrical characteristics of C-SiGe and CRSL-SiGe NSFETs. The results show that the proposed CRSL-SiGe NSFET achieves a 16% reduction in gate capacitance ( ${\mathrm {C}}_{\mathrm {GG}}$ ) while maintaining a comparable DC performance to C-SiGe NSFET. Additionally, an obvious improvement in gain of the inverter is achieved under various power. Moreover, the oscillation frequency of ring oscillators is increased and their delay is reduced under various power. These results indicate that CRSL-SiGe NSFET is a promising candidate for suppressing process variations and improving circuit performance in the advanced technology node.