Physical model and optimized design methodology for on-chip inductors

Abstract

In this thesis, the physical model of integrated inductors has been proposed for circuit simulation and optimized design. For accurate representing the losses in inductors, a new topology of model has been proposed and verified by simulation. Each component of the proposed model has been calculated from the process parameter and the geometric information of the inductor. Especially, for the exact calculation of the frequency dependent resistance of inductor line, the new physical method has been developed with the experimental study of the resistance and its proximity effect. By the comparison between measured and modeled data, we have shown that the proposed calculation method can estimate the variation of the resistance well when the frequency is varied. As a result, the other measured characteristics of the inductor, such as Q-factor and inductance, were well matched with the modeled. For easy usage of the proposed model, the user-interface program has been coded and we have shown that the program is useful in the optimization of the inductor structure for better performance. Finally, for the application of the proposed model into circuit simulation, the spice-compatible model, which components is all frequency independent, has been approximated successfully from the exact frequency dependent physical model.