Memory active region layout for improving memory performance

Abstract

SRAM designs based on GAA transistors are disclosed that provide flexibility for increasing channel widths of transistors at scaled IC technology nodes and relax limits on SRAM performance optimization imposed by FinFET-based SRAMs. GAA-based SRAM cells described have active region layouts with active regions shared by pull-down GAA transistors and pass-gate GAA transistors. A width of shared active regions that correspond with the pull-down GAA transistors are enlarged with respect to widths of the shared active regions that correspond with the pass-gate GAA transistors. A ratio of the widths is tuned to obtain ratios of pull-down transistor effective channel width to pass-gate effective channel width greater than 1, increase an on-current of pull-down GAA transistors relative to an on-current of pass-gate GAA transistors, decrease a threshold voltage of pull-down GAA transistors relative to a threshold voltage of pass-gate GAA transistors, and/or increases a β ratio of an SRAM cell.