Modeling and Parameter Extraction of CMOS On-Chip Spiral Inductors With Ground Shields

A new simple π-equivalent model with parameter extraction method is presented in this letter, to develop accurate models for spiral inductors on low-resistance CMOS substrate with ground shield structure. C-L-R network is introduced to model the ground loop in the lower metal strips, replacing the conventional C-R-C network. This model contains only ten frequency-independent components with explicit physical meaning, which has fewer elements and is easy to be extracted. Frequency responses of the extracted results are in excellent agreement with the measurements and EM simulations of inductors with different ground shields and layout designs up to 40 GHz. This proves the validity of the proposed model and parameter extraction method. Finally, extracted results of the inductors with different ground shields are compared and investigated.