Magnetic reinitialization of thin film magnetoresistive reproducing heads at the suspension level of media drive manufacturing
AssigneeInternational Business Machines Corporation
InventorsSamir Elias Abboud, Nickolas Christopher Apuzzo, Jeffrey Bernard Brown, Earl Albert Cunningham, David Malcolm Hannon, Raymond Patrick Mallette, Paul Sheldon Tyler, Steven Harry Voss, Albert John Wallash
Life of this patent
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Abstract
The magnetic states of MR reproducing heads are reinitialized during media drive manufacturing by applying initializing magnetic fields to the transducers after they have been manufactured and incorporated into media drive assemblies.
Claims38
A method for setting a magnetic state of a magnetoresistive device using a magnetizing apparatus including an air gap disposed between magnetic poles composed of a soft magnetic material and means for inducing a magnetic field in the air gap, the method including the steps of:
- forming a plurality of thin-film magnetoresistive transducers on a single substrate, each magnetoresistive transducer including a hard biased magnetoresistive element having a magnetic state;
- separating the thin-film magnetoresistive transducers by cutting the single substrate into a plurality of individual pieces;
- mounting each individual piece on a flexure, producing a head slider assembly;
- for at least one head slider assembly, setting the magnetic state of a hard biased magnetoresistive element in a magnetoresistive transducer mounted on the flexure by disposing the head slider assembly with respect to the magnetizing apparatus to place the hard biased magnetoresistive element in the air gap;
- and
- inducing a magnetic field in the air gap.
A method for setting a magnetic state of a magnetoresistive device using a magnetizing apparatus including an air gap disposed between magnetic poles composed of a soft magnetic material and means for inducing a magnetic field in the air gap, the method including the steps of:
- mounting a plurality of magnetoresistive transducers on a corresponding plurality of head slider assemblies, such that each magnetoresistive transducer includes a hard biased magnetoresistive element having a magnetic state and is mounted on a respective flexure;
- for at least one head slider assembly, setting the magnetic state of a hard biased magnetoresistive element in a magnetoresistive transducer mounted on the flexure by disposing the assembly with respect to the magnetizing apparatus to place the hard biased magnetoresistive element in the air gap;
- inducing a magnetic field in the air gap;
- and
- mounting the at least one assembly in a media drive.
A method for setting a magnetic state of a magnetoresistive device using a magnetizing apparatus including an air gap disposed between magnetic poles composed of a soft magnetic material and means for inducing a magnetic field in the air gap, the method including the steps of:
- forming a plurality of thin-film magnetoresistive transducers on a single substrate, each magnetoresistive device including a magnetoresistive element having a magnetic state;
- separating the thin-film magnetoresistive transducers by cutting the single substrate into a plurality of individual pieces;
- mounting each individual piece on a flexure, producing a head slider assembly;
- for at least one slider assembly, setting the magnetic state of a hard biased magnetoresistive element in a magnetoresistive transducer mounted on the flexure by disposing the assembly with respect to the magnetizing apparatus to place the hard biased magnetoresistive element in the air gap, the magnetic field having a strength in the range of 450 to 4500 gauss;
- and
- inducing a magnetic field in the air gap.
A method for setting a magnetic state of each magnetoresistive transducer of a plurality of magnetoresistive transducers using a magnetizing apparatus that includes a plurality of cell magnets including a corresponding cell magnet for each magnetoresistive transducer, each cell magnet further including an air gap disposed between a pole members that are composed of a soft magnetic material, and the apparatus further including means for inducing a magnetic field in the air gap, the method including the steps of:
- forming a plurality of thin-film magnetoresistive transducers on a single substrate, each magnetoresistive transducer including a magnetoresistive element having a magnetic state;
- separating the thin-film magnetoresistive transducers by cutting the single substrate into a plurality of individual pieces;
- mounting each individual piece on a respective flexure, producing a head slider assembly from a plurality of assemblies;
- for each assembly in the plurality of head slider assemblies, setting the magnetic state of each hard biased magnetoresistive element in each magnetoresistive transducer mounted on each flexure substantially simultaneously by disposing each assembly in each air gap of each cell magnet;
- and
- inducing a magnetic field in each air gap of each cell magnet.
A method for setting a magnetic state of each magnetoresistive transducer of a plurality of magnetoresistive transducers using a magnetizing apparatus that includes a plurality of cell magnets including a corresponding cell magnet for each magnetoresistive transducer, each cell magnet further including an air gap disposed between pole members that are composed of a soft magnetic material, and the apparatus further including means for inducing a magnetic field in the air gap, the method including the steps of:
- mounting the plurality of magnetoresistive transducers on a corresponding plurality of flexures, producing a corresponding plurality of head slider assemblies, such that each magnetoresistive transducer includes a hard biased magnetoresistive element having a magnetic state and being mounted on a respective flexure;
- for each assembly in the plurality of head slider assemblies, setting the magnetic state of each hard biased magnetoresistive element in each magnetoresistive transducer mounted on each flexure substantially simultaneously by disposing each assembly in each air gap of each cell magnet;
- and
- inducing a magnetic field in each air gap of each cell magnet.
A method for setting a magnetic state of each magnetoresistive transducer of a plurality of magnetoresistive transducers using a magnetizing apparatus that includes a plurality of cell magnets including a corresponding cell magnet for each magnetoresistive transducer, each cell magnet further including an air gap disposed between a pole members that are composed of a soft magnetic material, and the apparatus further including means for inducing a magnetic field in the air gap, the method including the steps of:
- mounting the plurality of magnetoresistive transducers on a corresponding plurality of media drive suspension assemblies, such that each magnetoresistive transducer includes a hard biased magnetoresistive element having a magnetic state and being mounted on a respective media drive suspension assembly;
- for each suspension assembly in the plurality of suspension assemblies, setting the magnetic state of each hard biased magnetoresistive element in each magnetoresistive transducer mounted on each suspension assembly substantially simultaneously by disposing each suspension assembly in each air gap of each cell magnet;
- and
- inducing a magnetic field in each air gap of each cell magnet.
Dependencies are inferred from the claim text.