Predictive spiral inductor compact model for frequency and time domain

Abstract

A highly accurate predictive inductor model for integrated symmetric inductors with center tap and patterned ground shield is presented. This model is based on a modified Greenhouse algorithm where current crowding due to skin and proximity effects is included by considering the spread in parallel sub-loop inductances. This scalable symmetrical inductor equivalent circuit model covers all operating conditions, and yet only requires dimensions and back-end layer thicknesses. We have verified this scalable model for a large number of inductors from three industrial IC processes and found excellent agreement with measured inductances, Q-factors, and resonance frequencies.