Seagate Technology Incorporated

Allan E Schultz

William H Nunne

L Vincent Ruscello

Kenneth P Ash

Richard P Larson

Frank Edgar Stageberg

Peter K George

Feng Y Wang

James Keith Price

Brian S Zak

Elzbieta Janina Haftek

Frank S Stageberg

Patrick Joseph Ryan

Peter I Bonyhard

William P Wood

Jumna P Ramdular

Arthur Calderon

Leroy L Longworth

Duane C Phinney

Juan J Fernandez-De Castro

A process of forming a two-piece pole for an inductive write head involves first forming a first pole piece having a width between opposite side surfaces defining a gap width of a transducing gap at an air bearing surface of the head. The process next involves forming a second pole piece having a first region remote from the air bearing surface and a second region extending from the first region toward the air bearing surface. The first region is wider than the width of the first pole piece. The second pole piece is formed so that at least a portion of the second region is contiguous a portion of the first pole piece and so that no sharp external corners exist between the first pole tip piece and the second pole piece within a pole tip region of the head.

Method for forming a narrow track inductive write head having two-piece pole

A two-piece pole for an inductive write head has a first pole piece in the tip region contiguous the gap and confronting the other pole across the gap. The first pole piece has a width defining the gap width of the write head at the air bearing surface. A second pole piece is connected to the first pole piece and extends to the back gap. At least a portion of the second pole piece is connected to the first pole piece and has a width larger than the width of the first pole piece. The second pole piece means has surfaces within the pole tip region that intersect at external corners facing the gap, at least two surfaces of each of these external corners being joined at an obtuse angle so that none of said external corner is a sharp external corner, thereby minimizing fringe fields. In one form, a pole cap between the first and second pole pieces has a trapezoidal configuration forming the obtuse angles.

Narrow track inductive write head having a two-piece pole

A magnetic structure is formed by depositing a layer of diamond-like carbon onto the exposed surface of an a first material and depositing a layer of second material onto the layer of diamond-like carbon. A photoresist is applied to the exposed surface of the second layer and is patterned in the form of the desire structure. The exposed portions of the second layer are removed with a wet etchant that does not attack the diamond-like carbon layer. Thereafter, any remaining photoresist is removed.

Diamond-like carbon and oxide bilayer insulator for magnetoresistive transducers

A thin film magnetic transducer supported on a substrate includes a coil that terminates at pads supported on the substrate. A layer of diamond-like carbon material encapsulates the head, substrate and coil, but not the pads. A thin layer of diamond-like carbon is deposited over the exposed portions of the transducer, coil and substrate. Three techniques are described for exposing the pads including employing a photoresist mask, depositing an adhesive layer of silicon over the conductive paths but not the pads, and using a photoresist mask to etch the diamond-like carbon layer over the pads and breaking down the silicon adhesive layer with a design voltage.

Diamond-like carbon encapsulation of magnetic heads

MR sensor having thick active region between two thinner inactive MR

Diamond-like carbon wet etchant stop for formation of magnetic

An inverted magnetoresistive head is disclosed. The inverted magnetoresistive head includes a reader positioned on top of a writer. The writer includes a bottom pole, a polymer insulator, a write gap, a pole tip and a top pole. The reader includes a bottom shield, a first reader gap, a magnetoresistive element, electrical contacts, a second reader gap and a shield.

Inverted magnetoresistive head

A method of producing a magnetoresistive read transducer with improved longitudinal bias due to high exchange coupling is disclosed. A layer of antiferromagnetic material is sputtered deposited onto a layer of ferromagnetic material in the absence of a magnetic field and at a power density below 0.7 W/cm.sup.2. The layers of ferromagnetic material and antiferromagnetic material are annealed at a low temperature of between 200.degree. C. and 250.degree. C. for between 6 and 26 hours.

No-field, low power FeMn deposition giving high exchange films

A diamond-like carbon mask is formed on the surface of the magnetic material for ion-milling the magnetic material into a magnetic pole of a transducer. The mask is formed by depositing a layer of diamond-like carbon over the magnetic material. Successive layers of photoresist, SiO.sub.2 and photoresist are applied over the magnetic material. The second layer of photoresist is patterned in the shape of the pole being formed. The exposed insulating layer is etched with an etchant that does not attack the diamond-like carbon, the exposed portions of the photoresist are exposed and removed, and the exposed portion of the diamond-like carbon is etched with an oxygen etchant. The remaining photoresist is washed away to remove the remaining insulating material. In one form of the invention, a layer of SiO.sub.2 may additionally be formed over the diamond-like carbon to protect the diamond-like carbon from being affected by any undercut of the photoresist by the oxygen etchant. The SiO.sub.2 layer is etched prior to etching the diamond-like carbon. The mask is used to ion mill the magnetic material to the desired pole.

Diamond-like carbon for ion milling magnetic material

Amorphous diamond-like carbon gaps in magnetoresistive heads

A method of fabricating an inverted magnetoresistive head is disclosed. The method includes fabricating a writer. The writer includes a bottom pole positioned within a recessed substrate. The bottom pole is filled with copper coils and polymer. A write gap, a pole tip, and a top pole/bottom shield are fabricated on a portion of the polymer. A top surface of both the polymer and the write gap are planarized to provide a substantially smooth surface upon which a reader can be placed. The reader is fabricated on top of the writer and includes a first reader gap, a magnetoresistive element, a second reader gap, and a shield.

Method of fabricating an inverted magnetoresistive head

A wafer level test structure and method detects multiple magnetic domains and magnetic domain instability in a test magnetic element. The apparatus comprises a first MR sensor designed to be held in a single magnetic domain by shape anisotropy and a second MR sensor having a permanent magnet to hold the element in a single magnetic domain. A circuit connects the first and second MR sensors to detect differences between the changes in resistance between the first and second sensors in the presence of a magnetic field or differences in resistance after the application and release of a magnetic field. The circuit is preferably a balance circuit in which imbalance in the presence of a magnetic field indicates the presence of multiple magnetic domains in at least one of the test sensors. Magnetic domain stability may be tested by applying an external field to disrupt the existing single domain state of the test sensors, and thereafter detecting differences in resistance of the sensors during reversal of the magnetic field.

Wafer level test structure for detecting multiple domains and magnetic

A device and method for determining alignment accuracy between magnetoresistive elements and contacts of magnetoresistive heads formed on a wafer are disclosed. A first alignment test structure is defined using a first photomask. The first alignment test structure is formed from a first material having a first characteristic sheet resistivity. A second alignment test structure is defined using a second photomask. The second alignment test structure is formed from a second material having a second characteristic sheet resistivity lower than the first characteristic sheet resistivity. The second alignment test structure is formed in contact with the first alignment test structure. A resistance value is dependent upon the first and second characteristic sheet resistivities and upon alignment between the first alignment test structure and the second alignment test structure such that changes in alignment between the first and second alignment test structures result in changes in the resistance value. Changes in the resistance value are indicative of changes in alignment between magnetoresistive elements and contacts formed on the wafer.

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Saint Paul, MN, United States of America

Allan E Schultz