Modeling of spiral inductors on lossy substrates for RFIC applications

Abstract

A modeling technique for planar microstrip spiral inductors in the presence of lossy media, such as in CMOS and bipolar technologies, is presented. The new model for spiral inductors incorporates the frequency dependent substrate effects via analysis of the the 'skineffect' mode of the microstrip structure.

Physical modeling of spiral inductors on silicon

“…In this case, the high frequency current recedes to the bottom surface of the wire, which is above the ground plane [22]- [24]. The attenuation of the current density in A/m 2 ) as a function of distance away from the bottom surface can be represented by the function (11) The current in A) is obtained by integrating over the wire cross-sectional area. Since only varies in the direction, can be calculated as (12) where is the physical thickness of the wire.…”

Optimization Ofspiral Inductor With Different Inner Diameters

“…There have been numerous publications on spiral inductor design at microwave frequencies [1][2][3][4][5]. The implementation of integrated inductors has been great challenge in designing high frequency applications.…”

New coupled EM and circuit simulation flow for integrated spiral inductor by introducing symbolic simplified expressions

“…From the results of the simulations it is crucial to extract parameters of models that can describe synthetically the device or the process under evaluation. For instance, microstrip spiral inductors, that are fundamental components in the modern integrated electronics [1], [2], require modelling techniques which handle properly the loss mechanisms involved, particularly those losses that occur in semiconductor substrate [4]. The inductance can be computed exactly by solving Maxwell's equations [5] but to facilitate the design of such components, significant work has gone into modelling spiral inductors using lumped circuit models that takes into account the parasitic resistors and capacitors.…”