Method of manufacturing a lead overlay bottom spin valve with improved side reading
AssigneeHeadway Technologies, Inc.
InventorsMoris M. Dovek, Tai Min
Life of this patent
Estimating the term…
Abstract
In bottom spin valves of the lead overlay type the longitudinal bias field that stabilizes the device tends to fall off well before the gap is reached. This problem has been overcome by providing a manufacturing process that includes inserting an additional antiferromagnetic layer between the hard bias plugs and the overlaid leads. This additional antiferromagnetic layer and the lead layer are etched in the same operation to define the read gap, eliminating the possibility of misalignment between them. The extra antiferromagnetic layer is also longitudinally biased so there is no falloff in bias strength before the edge of the gap is reached. A process for manufacturing the device is also described.
Claims16
A process for manufacturing a magnetic read head, comprising:
- providing a bottom spin valve, whose lowest layer is a first antiferromagnetic layer that has a first blocking temperature, having two opposing sides that slope downwards away from a central horizontal area;
- forming on said sloping sides two opposing plugs of magnetic hard bias material separated by a first gap;
- forming a capping layer on said central horizontal area;
- on said hard bias plugs and said capping layer, depositing a second antiferromagnetic layer having a second blocking temperature that is less than said first blocking temperature;
- on said second antiferromagnetic layer, depositing a conductive lead layer;
- patterning both said second antiferromagnetic layer and said conductive lead layer to form a second gap that is centrally located over said central and that is narrower than said first gap;
- heating said first antiferromagnetic layer at a temperature that is greater than said first blocking temperature for a first period of time in a first magnetic field;
- and
- then heating said second antiferromagnetic layer at a temperature that is greater than said second blocking temperature and less than said first blocking temperature for a second period of time in a second magnetic field.
A process for manufacturing a magnetic read head, comprising:
- providing a bottom spin valve, whose lowest layer is a first antiferromagnetic layer that has a first blocking temperature, having two opposing sides that slope downwards away from a central horizontal area;
- forming on said sloping sides two opposing plugs of magnetic hard bias material separated by a first gap;
- forming a capping layer on said central horizontal area;
- on said hard bias plugs, depositing a layer of ferromagnetic material;
- on said layer of ferromagnetic material and said capping layer, depositing a second antiferromagnetic layer having a second blocking temperature that is less than said first blocking temperature;
- on said second antiferromagnetic layer, depositing a conductive lead layer;
- patterning both said second antiferromagnetic layer and said conductive lead layer to form a second gap that is centrally located over said central and that is narrower than said first gap;
- heating said first antiferromagnetic layer at a temperature that is greater than said first blocking temperature for a first period of time in a first magnetic field;
- and
- then heating said second antiferromagnetic layer at a temperature that is greater than said second blocking temperature and less than said first blocking temperature for a second period of time in a second magnetic field.
Dependencies are inferred from the claim text.