A Wide-Band Equivalent Circuit Model for CMOS On-Chip Spiral Inductor

This paper presents a new wide-band spiral inductor model on silicon substrate especially in heavily doped silicon substrate process. Skin effect and proximity effect are well predicted by using a ladder `4-element' structure and a power resistor. For low resistively silicon substrate, since all metal lines couple laterally to each other through the conductive substrate, the electric coupling between lines can be modeled by a parallel combination of resistance and capacitance. The proposed model has been verified with measured data of spiral inductor fabricated in a 2P4M CMOS silicon process. The proposed model shows well agreement with measured data over a wide-band frequency range