Ferromagnetic RF integrated inductor with closed magnetic circuit structure

Closed magnetic circuit type ferromagnetic RF integrated inductors have been fabricated based on MEMS-like micro fabrication techniques. The taper etching process greatly helped to endure sufficient magnetic flux flow at the edge of the top and bottom magnetic layers. Air cores and three different sandwich type ferromagnetic inductors are also microfabricated. Measured results exhibited the quality factor Q=12, being highest among the published data of ferromagnetic RF integrated inductor at 1 GHz.