Qisheng Liu. Adaptive optimization of ring oscillators based on process-circuit Co-design

Abstract

Аs CMOS technology approaches its physical and economic limits, Design-Technology Co Optimization (DTCO) has become a critical approach to tapping circuit potential within a constrained process window. Targeting ring oscillators (ROs), this paper proposes an adaptive process-circuit co-optimization scheme. A parameter-exploration framework is established using a multi-objective composite reward function and an improved greedy genetic algorithm. Source/drain extension (EXT) doping is adopted as a low-risk tuning knob, and a staged quantitative-loss-function-driven BSIM4 model extraction strategy is employed to achieve high-fidelity mapping from TCAD to SPICE. Simulation results show that an approximately 6% increase in EXT doping yields a 10.76% rise in RO frequency and an around 11% improvement in the energy delay product (EDP). The proposed method can substantially enhance circuit performance under a controllable power budget and is applicable to other advanced process nodes.