Method and a mechanism capable of annealing a gmr sensor
AssigneeInstitute of Sensor Technology, Gansu Academy of Science
InventorsGenliang Han, Yuzhe Song
Life of this patent
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Abstract
A MR structure that comprises ferromagnetic layers separated by a spacer layer is formed on a substrate. One of the ferromagnetic layer is a pinned layer whose magnetic orientation is substantially fixed during operation. An insulating layer is deposited on the MR structure followed by deposition of a metallic layer. The metallic layer is patterned in to heat resistor. The MR structure is annealed by use of the heat resistor and an external magnetic field. After annealing, the insulating layer and the heat resistor are removed.
Claims8
A method of forming a first and second MR structures, wherein each MR structure comprises a pinned layer, the method comprising:
- forming the first and second MR structures that comprises:
- depositing a pinned layer, a non-magnetic spacing layer, and a free layer on a substrate, wherein the pinned layer and the free layer are ferromagnetic layers;
- depositing an insulating layer;
- and
- patterning the insulating layer in to a first and second heat resistors, wherein the first and second heat resistors are respectively on the insulating layers of the first and second MR structures;
- annealing the first and second MR structures, comprising:
- providing a magnetic field along a first magnetic direction;
- raising the temperature of the pinned layer of the first MR structure to or above its blocking temperature by feeding current through the first heat resistance;
- cooling down the first MR structure by removing the current from the first resistance;
- realigning the magnetic field along a second magnetic direction;
- raising the temperature of the pinned layer of the second MR structure to or above its blocking temperature by feeding current through the second heat resistance;
- and
- cooling down the second MR structure by removing the current from the second resistance;
- and
- removing the insulating layer and the first and second heat resistors.
Dependencies are inferred from the claim text.