Process-Variation-Aware Rule-Based Optical Proximity Correction for Analog Layout Migration

Optical proximity correction (OPC) is invaluable to precise layout manufacturing in the advanced nanometer technologies. However, lack of research activity on OPC for analog integrated circuits has currently led to sole dependence on digital solutions. In this paper, we propose a rule-based OPC (RB-OPC) methodology with process variation (PV) consideration, which is integrated into an analog layout migration process. Based on the unique features of analog layouts, the accuracy limitation of RB-OPC is compensated by local wire widening and wire shifting operations during layout migration. Moreover, innovative PV-band shifting is deployed to preserve analog circuit performance against PV. According to our experimental results, the proposed analog layout migration with PV-aware RB-OPC can achieve much higher efficiency with an even lower mask complexity and an acceptable edge placement error compared to some well-known commercial and academic digital solutions. The circuit performance by using our proposed methodology is also better than that from alternative methods in the mismatch scenarios due to our special PV-band handling on transistor gates.