A novel miniature planar inductor

The conventional inductor consists of cores and wound wires, which are obstacles for the integration with other devices. The planar inductor, which has planar coils and magnetic layers in place of cores and wires, is fabricated on a substrate. Therefore it can be integrated with other devices, and it will be a fundamental element for the future magnetic IC. In this paper two kinds of planar inductors are described. One is the outer type, which has the larger inductance than any other planar inductor. The other is the inner type, which has the possibility for a variable inductor.