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CN-122003100-A - Magnetic sensor and method for manufacturing the same

CN122003100ACN 122003100 ACN122003100 ACN 122003100ACN-122003100-A

Abstract

The present invention relates to a magnetic sensor and a method of manufacturing the same. The magnetic sensor (1) has at least one magnetic field detection element (2) and at least one first soft magnetic layer (3). At least one magnetic field detection element (2) has a first magnetization fixed layer (63), a magnetization free layer (61) whose magnetization direction changes with respect to an external magnetic field, and a first nonmagnetic layer (62). The first magnetization fixed layer (63), the magnetization free layer (61), and the first nonmagnetic layer (62) are arranged in the order of the magnetization free layer (61), the first nonmagnetic layer (62), and the first magnetization fixed layer (63) in a first direction, and the magnetization direction of the first magnetization fixed layer (63) is fixed to the first direction. The at least one first soft magnetic layer (3) is opposite to the at least one magnetic field detection element (2) in a first direction.

Inventors

  • Ohmura Hiroaki
  • KOBAYASHI

Assignees

  • TDK株式会社

Dates

Publication Date
20260508
Application Date
20251029
Priority Date
20241101

Claims (18)

  1. 1. A magnetic sensor, wherein, Having at least one magnetic field detecting element and at least one first soft magnetic layer, The at least one magnetic field detection element has a first magnetization fixed layer, a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, and a first nonmagnetic layer, The first magnetization pinned layer, the magnetization free layer, and the first nonmagnetic layer are arranged in the order of the magnetization free layer, the first nonmagnetic layer, and the first magnetization pinned layer in a first direction, a magnetization direction of the first magnetization pinned layer is pinned to the first direction, and the at least one first soft magnetic layer is opposite to the at least one magnetic field detection element in the first direction.
  2. 2. The magnetic sensor according to claim 1, wherein, The magnetic sensor has at least one second soft magnetic layer opposite to the at least one magnetic field detection element in the first direction, the at least one magnetic field detection element being located between the at least one first soft magnetic layer and the at least one second soft magnetic layer.
  3. 3. The magnetic sensor according to claim 2, wherein, The magnetization free layer has a long axis, at least one of the first soft magnetic layer and the second soft magnetic layer has a long axis, and the long axis of the magnetization free layer is parallel to the long axis of at least one of the first soft magnetic layer and the second soft magnetic layer.
  4. 4. A magnetic sensor according to claim 1 to 3, wherein, The first nonmagnetic layer is composed of an insulating layer.
  5. 5. A magnetic sensor according to claim 1 to 3, wherein, The at least one magnetic field detection element has a second magnetization fixed layer and an intermediate layer made of a nonmagnetic metal, the first magnetization fixed layer, the magnetization free layer, the first nonmagnetic layer, the second magnetization fixed layer, and the intermediate layer are arranged in the order of the magnetization free layer, the first nonmagnetic layer, the first magnetization fixed layer, the intermediate layer, the second magnetization fixed layer in the first direction, The magnetization direction of the second magnetization fixed layer is fixed to be opposite to the magnetization direction of the first magnetization fixed layer.
  6. 6. A magnetic sensor according to claim 1 to 3, wherein, The at least one magnetic field detection element has a second magnetization fixed layer and a second nonmagnetic layer, the first magnetization fixed layer, the magnetization free layer, the first nonmagnetic layer, the second magnetization fixed layer, and the second nonmagnetic layer are arranged in the first direction in the order of the second magnetization fixed layer, the second nonmagnetic layer, the magnetization free layer, the first nonmagnetic layer, and the first magnetization fixed layer, The magnetization direction of the second magnetization fixed layer is fixed to be opposite to the magnetization direction of the first magnetization fixed layer.
  7. 7. A magnetic sensor according to claim 1 to 3, wherein, The at least one magnetic field detecting element has an antiferromagnetic layer, the first magnetization fixed layer, the magnetization free layer, the first nonmagnetic layer, and the antiferromagnetic layer are arranged in the order of the magnetization free layer, the first nonmagnetic layer, the first magnetization fixed layer, and the antiferromagnetic layer in the first direction, The magnetization direction of the first magnetization pinned layer is pinned by exchange coupling with the antiferromagnetic layer.
  8. 8. A magnetic sensor according to claim 1 to 3, wherein, The at least one magnetic field detection element has an intermediate layer composed of a nonmagnetic metal, a second magnetization fixed layer, and an antiferromagnetic layer, the first magnetization fixed layer, the magnetization free layer, the first nonmagnetic layer, the intermediate layer, the second magnetization fixed layer, and the antiferromagnetic layer being arranged in the order of the magnetization free layer, the first nonmagnetic layer, the first magnetization fixed layer, the intermediate layer, the second magnetization fixed layer, and the antiferromagnetic layer in the first direction, The magnetization direction of the second magnetization pinned layer is pinned to a direction opposite to the magnetization direction of the first magnetization pinned layer by exchange coupling with the antiferromagnetic layer.
  9. 9. A magnetic sensor according to claim 1 to 3, wherein, In a state where the external magnetic field is not present, the magnetization direction of the magnetization free layer is oriented in a direction orthogonal to the first direction.
  10. 10. A magnetic sensor according to claim 1 to 3, wherein, In a state where the external magnetic field is not present, the magnetization direction of the magnetization free layer forms a vortex shape in a plane orthogonal to the first direction.
  11. 11. The magnetic sensor of claim 10, wherein, The at least one magnetic field sensing element is a plurality of magnetic field sensing elements, In a state where the external magnetic field is not present, the magnetization direction of the magnetization free layer of each magnetic field detection element forms a vortex shape in a plane orthogonal to the first direction, The plurality of magnetic field detection elements are connected in series and opposed to one of the first soft magnetic layers in the first direction, A part and the rest of the plurality of magnetic field detection elements are located on both sides of a plane of the first soft magnetic layer including a center line parallel to the first direction, and magnetization directions at the center of the vortex shape are opposite to each other.
  12. 12. A magnetic sensor according to claim 1 to 3, wherein, The at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The magnetic sensor has first and second element units each including a part of the plurality of magnetic field detection elements, The first element unit and the second element unit form a series-connected group, one end of the group is connected with a power supply, the other end is grounded, The magnetic sensor has an output portion located between the first element unit and the second element unit, The magnetization direction of the first magnetization pinned layer of the first element unit and the magnetization direction of the first magnetization pinned layer of the second element unit are opposite to each other.
  13. 13. A magnetic sensor according to claim 1 to 3, wherein, The at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The magnetic sensor has first to fourth element units respectively including a part of the plurality of magnetic field detection elements, The first element unit and the second element unit form a first group connected in series, the third element unit and the fourth element unit form a second group connected in series, one ends of the first group and the second group are connected with a power supply, the other ends are grounded, The first element unit and the fourth element unit are arranged on the power supply side, the second element unit and the third element unit are arranged on the ground side, The magnetic sensor has a differentiator for determining a difference between an output between the first element unit and the second element unit and an output between the third element unit and the fourth element unit, The magnetization directions of the first magnetization pinned layers of the first element unit and the third element unit are the same, and the magnetization directions of the first magnetization pinned layers of the second element unit and the fourth element unit are opposite to the magnetization directions of the first magnetization pinned layers of the first element unit and the third element unit.
  14. 14. The magnetic sensor of claim 12, wherein, The at least one first soft magnetic layer is one first soft magnetic layer, the one first soft magnetic layer being opposite to the first to fourth element units.
  15. 15. A method for manufacturing a magnetic sensor, wherein, The device comprises: A step of manufacturing a first element unit and a second element unit such that the first element unit and the second element unit constitute a series-connected group, one end of the group is connected to a power source, the other end is grounded, an output section is provided between the first element unit and the second element unit, and at least one magnetic field detection element is provided in each of the first element unit and the second element unit, The at least one magnetic field detection element provided with the first element unit and the second element unit has: A step of arranging a first magnetization fixed layer, a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, a first nonmagnetic layer, and an antiferromagnetic layer in the order of the magnetization free layer, the first nonmagnetic layer, the first magnetization fixed layer, and the antiferromagnetic layer in a first direction; A step of locally heating the first element unit while applying a magnetic field in the first direction to magnetize the first magnetization fixed layer of the first element unit, and And a step of locally heating the second element unit while applying a magnetic field in a second direction opposite to the first direction to magnetize the first magnetization fixed layer of the second element unit.
  16. 16. The manufacturing method according to claim 15, wherein, The first element unit and the second element unit are locally heated by irradiation with laser light.
  17. 17. A method for manufacturing a magnetic sensor, wherein, The device comprises: A step of manufacturing first to fourth element units such that the first element unit and the second element unit form a first group connected in series, the third element unit and the fourth element unit form a second group connected in series, one ends of the first group and the second group are connected to a power source, the other ends are grounded, the first element unit and the fourth element unit are arranged on the power source side, the second element unit and the third element unit are arranged on the ground side, and at least one magnetic field detection element is provided in each of the first to fourth element units, and A step of creating a differentiator for obtaining a difference between an output between the first element unit and the second element unit and an output between the third element unit and the fourth element unit, The at least one magnetic field detection element provided with the first to fourth element units has: A step of arranging a first magnetization fixed layer, a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, a first nonmagnetic layer, and an antiferromagnetic layer in the order of the magnetization free layer, the first nonmagnetic layer, the first magnetization fixed layer, and the antiferromagnetic layer in a first direction; A step of locally heating the first element unit and the third element unit while applying a magnetic field in the first direction to magnetize the first magnetization fixed layer of the first element unit and the third element unit, and And a step of locally heating the second element unit and the fourth element unit while applying a magnetic field in a second direction opposite to the first direction to magnetize the first magnetization fixed layer of the second element unit and the fourth element unit.
  18. 18. The manufacturing method according to claim 17, wherein, The first to fourth element units are locally heated by irradiating laser light.

Description

Magnetic sensor and method for manufacturing the same Technical Field The present disclosure relates to a magnetic sensor and a method of manufacturing the same. Background A magnetic sensor using the magnetoresistance effect generally has a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, a magnetization fixed layer whose magnetization direction is fixed, and a nonmagnetic layer located between the magnetization free layer and the magnetization fixed layer. Japanese patent application laid-open No. 2018-6598 describes a magnetic sensor in which the magnetization direction of a magnetization fixed layer is fixed in the direction in which a magnetization free layer, a nonmagnetic layer, and a magnetization fixed layer are stacked. Disclosure of Invention The present disclosure provides a magnetic sensor in which the magnetization direction of a magnetization pinned layer is pinned to the lamination direction of a magnetization free layer, a nonmagnetic layer, and a magnetization pinned layer, and the magnetization direction of the magnetization pinned layer is less likely to be inclined from the lamination direction. The magnetic sensor of the present disclosure has at least one magnetic field detection element and at least one first soft magnetic layer. The at least one magnetic field detection element has a first magnetization fixed layer, a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, and a first nonmagnetic layer. The first magnetization pinned layer, the magnetization free layer, and the first nonmagnetic layer are arranged in the first direction in the order of the magnetization free layer, the first nonmagnetic layer, and the first magnetization pinned layer, and the magnetization direction of the first magnetization pinned layer is pinned to the first direction. The at least one first soft magnetic layer is opposite to the at least one magnetic field detection element in a first direction. Drawings Fig. 1a to 1b are schematic configuration diagrams of a magnetic sensor according to a first embodiment. Fig. 2 is a schematic configuration diagram of a magnetic sensor according to a second embodiment. Fig. 3 is a schematic configuration diagram of a magnetic sensor according to a third embodiment. Fig. 4 is a schematic configuration diagram of a magnetic sensor according to a fourth embodiment. Fig. 5 is a schematic configuration diagram of a magnetic sensor according to a fifth embodiment. Fig. 6a to 6c are schematic configuration diagrams of magnetic sensors according to a sixth embodiment and a comparative example. Fig. 7 is a schematic configuration diagram of a magnetic sensor according to a seventh embodiment. Fig. 8 is a schematic configuration diagram of a magnetic sensor according to an eighth embodiment. Fig. 9 is a schematic configuration diagram of a magnetic sensor according to a ninth embodiment. Description of the reference numerals: magnetic sensor Magnetic field detection element First soft magnetic layer Second soft magnetic layer Upper electrode layer Laminate Lower electrode layer First to 14. Fourth element unit 61. Magnetization free layer 62. First nonmagnetic layer 63. First magnetization fixed layer Interlayer 65. Second magnetization fixed layer Second non-magnetic layer 67. Antiferromagnetic layer Detailed Description In the magnetic sensor described in japanese patent application laid-open No. 2018-6598, although the magnetization direction of the magnetization fixed layer is fixed to the lamination direction, the magnetization direction of the magnetization fixed layer may be inclined from the lamination direction by an external magnetic field orthogonal to the lamination direction. Tilting of the magnetization direction of the magnetization fixed layer may cause a decrease in the output of the magnetic sensor. Some embodiments of the present disclosure are described below with reference to the accompanying drawings. In the following description and the accompanying drawings, a direction (first direction) in which the plurality of layers of the laminate 6 are laminated is referred to as a Z direction. The direction from the laminate 6 toward the upper electrode layer 5 is referred to as the +z direction. The direction from the laminate 6 toward the lower electrode layer 7 or the substrate is referred to as the-Z direction. The direction orthogonal to the Z direction is referred to as the X direction. For convenience, the X direction is labeled in the figures, but the X direction may be any direction orthogonal to the Z direction. Unless otherwise indicated, hollow arrows in the drawings indicate magnetization directions of the first magnetization fixed layer 63, the second magnetization fixed layer 65. The thick line with an arrow indicates the magnetization direction of the magnetization free layer 61 in a state without an external magnetic field (hereinaf