US 12,455,328 B2
Magnetic sensor, position detector including the same, and method of manufacturing magnetic sensor
Daisuke Nakamura, Nagaokakyo (JP); and Takahiro Ibusuki, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Jan. 8, 2024, as Appl. No. 18/406,544.
Application 18/406,544 is a continuation of application No. PCT/JP2022/023980, filed on Jun. 15, 2022.
Claims priority of application No. 2021-128367 (JP), filed on Aug. 4, 2021.
Prior Publication US 2024/0219489 A1, Jul. 4, 2024
Int. Cl. G01R 33/09 (2006.01); G01R 33/00 (2006.01); H10N 50/10 (2023.01)
CPC G01R 33/093 (2013.01) [G01R 33/0052 (2013.01); G01R 33/098 (2013.01); H10N 50/10 (2023.02)] 20 Claims
OG exemplary drawing
 
1. A magnetic sensor comprising:
a first magnetoresistance effect element;
a second magnetoresistance effect element;
a third magnetoresistance effect element; and
a fourth magnetoresistance effect element; wherein
the first magnetoresistance effect element, the second magnetoresistance effect element, the third magnetoresistance effect element, and the fourth magnetoresistance effect element are electrically connected to each other to define a bridge circuit;
upon application of a signal magnetic field, the second magnetoresistance effect element and the third magnetoresistance effect element experience a resistance change opposite in direction to a resistance change of the first magnetoresistance effect element and the fourth magnetoresistance effect element;
each of the first magnetoresistance effect element, the second magnetoresistance effect element, the third magnetoresistance effect element, and the fourth magnetoresistance effect element includes a plurality of magnetoresistance effect stacks electrically connected to each other;
each of the plurality of magnetoresistance effect stacks includes a magnetized fixed layer, a non-magnetic layer, and a magnetized free layer stacked in this order, a magnetization direction of the magnetized free layer being changeable according to the signal magnetic field;
in each of the first magnetoresistance effect element and the fourth magnetoresistance effect element, the magnetized fixed layer has a magnetization state fixed to a first direction in all of the plurality of magnetoresistance effect stacks;
in each of the second magnetoresistance effect element and the third magnetoresistance effect element, the magnetized fixed layer has a magnetization state fixed to a second direction opposite to the first direction in at least one of the plurality of magnetoresistance effect stacks, and others of the plurality of magnetoresistance effect stacks include at least one of a portion in which the magnetized fixed layer has a magnetization state fixed to a direction different from the second direction and a portion in which the magnetized fixed layer has a magnetization state where a magnetization direction changes according to the signal magnetic field; and
an output value of the magnetic sensor when an intensity of the signal magnetic field is zero is displaced from zero due to a difference between the magnetization state of a plurality of the magnetized fixed layers of the plurality of magnetoresistance effect stacks in each of the first magnetoresistance effect element and the fourth magnetoresistance effect element and the magnetization state of a plurality of the magnetized fixed layers of the plurality of magnetoresistance effect stacks in each of the second magnetoresistance effect element and the third magnetoresistance effect element.