An ultra-compact virtual source FET model for deeply-scaled devices: Parameter extraction and validation for standard cell libraries and digital circuits

Abstract

In this paper, we present the first validation of the virtual source (VS) charge-based compact model for standard cell libraries and large-scale digital circuits. With only a modest number of physically meaningful parameters, the VS model accounts for the main short-channel effects in nanometer technologies. Using a novel DC and transient parameter extraction methodology, the model is verified with simulated data from a well-characterized, industrial 40-nm bulk silicon model. The VS model is used to fully characterize a standard cell library with timing comparisons showing less than 2.7% error with respect to the industrial design kit. Furthermore, a 1001-stage inverter chain and a 32-bit ripple-carry adder are employed as test cases in a vendor CAD environment to validate the use of the VS model for large-scale digital circuit applications. Parametric Vdd sweeps show that the VS model is also ready for usage in low-power design methodologies. Finally, runtime comparisons have shown that the use of the VS model results in a speedup of about 7.6×.