SRAM critical yield evaluation based on comprehensive physical / statistical modeling, considering anomalous non-Gaussian intrinsic transistor fluctuations

Critical SRAM yield evaluation/analysis for more robust design optimizations against variation is presented based on comprehensive physical modeling and statistical analysis of transistor intrinsic fluctuations for 65 nm-node and beyond MOSFETs. Predictive atomistic-3D-TCAD simulations reveal the origins of the non-Gaussian Vth-distribution that causes large sigmaVth deviation from the Pelgrom-relationship for specific small gate length devices. By using realistic statistical compact-modeling and fast Monte Carlo circuit simulations, it was demonstrated that the appropriate cell-design recognizing the anomalous sigmaVth enables to rescue significant possible yield loss caused by the particular behaviors of the intrinsic transistor fluctuations.