A non-magnetic layer is laminated on a lower magnetic layer. A first upper
magnetic layer is formed on the non-magnetic layer so as to form a
magnetic core together with the lower magnetic layer and the non-magnetic
layer. The first upper magnetic layer has a first saturation magnetic flux
density and a first magnetostriction constant. An insulation layer is
formed on the non-magnetic layer. A thin film coil is provided in the
insulation layer. A second upper magnetic layer is formed on the
insulation layer so as to be at least above the thin film coil. The second
upper magnetic layer has a second saturation magnetic flux density and a
second magnetostriction constant. The first saturation magnetic flux
density is higher than the second saturation magnetic flux density. The
second magnetostriction constant is lower than the first magnetostriction
constant.
