Investigation and Optimization of Monolithic 3D Logic Circuits and SRAM Cells Considering Interlayer Coupling

Abstract

In this work, we comprehensively investigate the impact of interlayer coupling on monolithic 3D logic circuits and 6T SRAM cells using TCAD mixed-mode simulations. In addition to reduced interconnection length, monolithic 3D integration enables further performance enhancements with optimal layout. Our study indicates that minimum leakage, equivalent to the planar 2D circuits with dual reverse body biases, is achievable for circuits stacked in 3D fashion. Moreover, stacking NFET layer over the PFET tier facilitates larger design margins for SRAM cell stability and performance.