Modeling and Optimization of Substrate Electromagnetic Coupling and Isolation in Modern Lightly Doped CMOS Substrate

This paper presents a series of scalable equivalent circuits using an analytical method describing the electromagnetic coupling in the lightly doped CMOS substrate and the isolation structures such as the implanted guard ring. Implemented in Grace Semiconductor Manufacturing Corporation (GSMC) generic 0.13-mu m RF CMOS technology, the measurement and full-wave simulation are carried out to verify the proposed models in a broad frequency band ranging from 100 MHz to 40 GHz. By analyzing these layout-dependant models in detail, some layout and substrate characteristics impacting on guard ring performance are concluded and the design flow with guidelines for the guard ring structures implementation in engineering practice for RF signal isolation are presented.