An improved lumped-element equivalent circuit for on silicon integrated inductors

This paper presents an improved lumped-element equivalent circuit of silicon integrated inductors, that accurately describes the effect on the Q-factor of the electromagnetic coupling between the metal strips and the substrate. In the proposed model a magnetic coupling describes the interaction between the substrate and the spirals of metal. The equivalent circuit is extracted using a characterization procedure that, from two-port wide-band measurement of the S-parameters, automatically yields the value of the lumped-element via the method of least square minima.