Modeling, Design, and Manufacturing of Microfabricated Coils With High Inductance Density

This paper addresses the design and manufacturing of small-scale square planar coils with inductance densities ranging from 2 to 19 μH·mm
^-2
. The design strategy is based on both analytic formulas and finite-element method. Two different manufacturing techniques, based on copper and aluminum, respectively, are used for the coils fabrication, and the key aspects as well as the technological limits of each process are discussed. The inductance measurements performed on the completed coils show good agreement with the theoretical predictions, with typical discrepancy below 4%. Finally, the overall performances of the components are evaluated in terms of volumic inductance density and inductance-to-resistance ratio.