Patent ID: 11921172
Assignee: NVE CORPORATION
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 9:
10. A magnetoresistive sensor element with synthetic antiferromagnet biasing, the magnetoresistive sensor element comprising:
a reference structure including:
a reference ferromagnetic layer; and
a reference antiferromagnetic layer in direct contact with a reference pinned ferromagnetic layer,
wherein the reference pinned ferromagnetic layer is formed on an opposite side of a reference non-magnetic spacer from the reference ferromagnetic layer;

a GMR/TMR sensor including:
a sensing ferromagnetic layer formed on an opposite side of a spacer layer from the reference ferromagnetic layer of the reference structure;

a synthetic antiferromagnetic biasing structure including:
a biasing pinned magnetic structure formed on an opposite side of a sense non-magnetic spacer from a sense biasing ferromagnetic layer; and

an exchange-tuning spacer sandwiched between the sensing ferromagnetic layer of the GMR/TMR sensor and the sense biasing ferromagnetic layer of the synthetic antiferromagnetic biasing structure,
wherein the reference ferromagnetic layer and the sense biasing ferromagnetic layer are pinned in in-plane directions that are orthogonal to one another,
wherein the biasing of the sensing ferromagnetic layer is such that the magnetoresistance of the magnetoresistive sensor element has hysteresis resulting in less than a 5% response difference and is symmetric about the zero-bias condition of the external magnetic field directed orthogonal to a pinning direction of the biasing pinned ferromagnetic layer.