Magnetic sensor, method of manufacturing magnetic sensor, and sensitive element assembly

A method of manufacturing a magnetic sensor comprising:

• forming an underlayer by laminating a soft magnetic material with a predetermined saturation magnetization on a surface of a substrate by magnetron sputtering;
• forming a soft magnetic material layer with uniaxial magnetic anisotropy in a predetermined direction by laminating a soft magnetic material on the underlayer, the soft magnetic material for the soft magnetic material layer having small saturation magnetization compared to the soft magnetic material constituting the underlayer by magnetron sputtering, the soft magnetic material layer contacting the underlayer;
• and
• forming a plurality of sensitive elements at a portion of the soft magnetic material layer where the uniaxial magnetic anisotropy is imparted, the plurality of sensitive elements sensing a magnetic field.

A sensitive element assembly comprising:

• a substrate;
• and
• a plurality of sensitive elements each having at least one sensitive portion formed on a surface of the substrate and having a longitudinal direction and a transverse direction, the sensitive portion sensing a magnetic field by a magnetic impedance effect, wherein
• the sensitive portion in each of the sensitive elements includes a soft magnetic material layer composed of a soft magnetic material having uniaxial magnetic anisotropy in a direction intersecting the longitudinal direction and sensing the magnetic field, and a secondary soft magnetic material layer laminated between the substrate and the soft magnetic material layer, the secondary soft magnetic material layer being composed of a soft magnetic material with large saturation magnetization compared to the soft magnetic material constituting the soft magnetic material layer, and
• the secondary soft magnetic material layer contacts the soft magnetic material layer.