Physics-based wideband predictive compact model for inductors with high amounts of dummy metal fill

A computationally efficient physics-based wideband predictive inductor compact model is presented that is capable of evaluating the impact on inductance and quality factor of dummy metal fill-cells. In a modern integrated-circuit process, high amounts of these fill-cells are required to meet metal density rules and guarantee adjacent circuit integrity. The predictions made with this model are shown to be in agreement with data measured on symmetrical octagonal inductors realized in a 90-nm CMOS process with varying amounts of dummy metal fill-cells. We further provide all inductance equations, list additional sources of eddy current losses, and discuss layout modifications, which would further improve the performance of the integrated inductors

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