A CFET Unit Cell based MUX21 design strategy

With the Moore’s law approaching ultimate limitation, device structure has been revolutionary changing, from FinFET to GAA FET, and then a new semiconductor device structure, CFET, has been regarded the continuing structure after GAA. CFET has significant area miniaturization advantages, but its folding N/PFET vertically brings new difficulties in process flow and new strategies for design enablement like in standard cell library. In this paper, we proposed the design consideration priority in CFET unit cell constructed standard cell library, and give examples like MUX21in obeying our rule. Two different schematics of MUX21 are designed at multiple levels: process flow, layout, and circuit performance. The proposed rule in CFET unit cell for standard library cell and the specific DTCO flow in this MUX21 circuit can provide the pathway for other circuit designs of standard cell library composed of CFET unit cell.