Patent ID: 7643254
Filing Date: 2010-01-05
Classification: B82Y,G01R,G11B,G11C,H01F

Abstract:
1. A tunnel-effect type magnetic sensor comprising: a laminate which includes a laminate portion composed of a fixed magnetic layer in which its magnetization direction is fixed, an insulating barrier layer, and a free magnetic layer in which its magnetization direction is changed with respect to an exterior magnetic field, the layers being laminated in that order from the bottom or from the top, wherein the insulating barrier layer is formed of Mg—O, the free magnetic layer is formed of a plurality of soft magnetic layers which are laminated together, at least one non-magnetic metal layer provided in each place between the soft magnetic layers, and an enhancement layer which has a spin polarizability higher than that of the soft magnetic layers and which is located between the insulating barrier layer and a first soft magnetic layer, which is one of the soft magnetic layers provided at a position closest to the insulating barrier layer, the soft magnetic layers are magnetically coupled together and are all magnetized in the same direction, and the average thickness of the first soft magnetic layer is in the range of 5 to 60 Å.