发明名称 |
Magnetic sensors having an antiferromagnetic layer exchange-coupled to a free layer |
摘要 |
A magnetic sensor which detects an external magnetic field with the aid of a ferromagnetic free layer having a magnetic moment responsive to the external magnetic field. The magnetic sensor has an antiferromagnetic layer which is magnetically exchange-coupled to the free layer to produce an exchange bias field He which acts on the free layer to bias its magnetic moment along a certain orientation such as the transverse direction. The additional exchange bias field He is used in balancing a total transverse internal magnetic field Ht which is due to other fields generated by the sensor itself. The value of exchange bias field He is set, e.g., by selecting a certain thickness and a certain composition of the antiferromagnetic layer. The magnetic sensor of the invention can also have a non-magnetic spacer layer interposed between the free layer and the antiferromagnetic layer or be in contact with the free layer. The sensor can be a spin valve sensor, a tunnel valve sensor, or any magnetic sensor using the free layer and the magnetoresistive effect to detect the external magnetic field.
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申请公布号 |
US6542341(B1) |
申请公布日期 |
2003.04.01 |
申请号 |
US19990443039 |
申请日期 |
1999.11.18 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
CAREY MATTHEW JOSEPH;CHILDRESS JEFFREY ROBINSON;GURNEY BRUCE ALVIN |
分类号 |
G11B5/39;(IPC1-7):G11B5/127 |
主分类号 |
G11B5/39 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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