International Business Machines Corporation

Hitachi Global Storage Technologies Netherlands B.v.

Yiping Hsiao

Leping Li

Steven G Barbee

Eugene Henry Ratzlaff

Tony F Heinz

Richard Hsiao

Justin W Wong

Ciaran Avram Fox

Cherngye Hwang

Wen-Chien David Hsiao

Jila Tabib

Justin Wai-chow Wong

Richard Thomas Campbell

Son Van Nguyen

Joseph John Fatula, Jr

Andrew Chiu

Atul S Kumar

Eric Wayne Flint

Thao Pham

Michael Ming Hsiang Yang

Michael J Balconi-Lamica

David M Arken

Robert William Hitzfield

A disk drive thin-film write head has a first ferromagnetic pole tip that includes a pedestal pole layer and a capping layer on the pedestal pole layer. A substantial portion of the pedestal pole layer is formed of a lower-moment alloy and the capping layer is formed of a higher-moment alloy and is made thick enough to compensate for the lower-moment alloy in the pedestal pole layer. The pedestal pole layer may be a bilayer of two different NiFe alloys with the upper layer in the bilayer having a higher moment, and the capping layer may be a CoFe alloy. The width of the pedestal pole layer is substantially reduced to reduce the pole tip area exposed. The reduced pole tip area and the increased use of lower-moment alloys enable a thinner protective film to be used to protect the pole tips from corrosion.

Disk drive thin-film inductive write head with pole tip structure having reduced susceptibility to corrosion

A process is described for fabricating magnetic transducers with metallic thin films with a corrosion resistant surface produced by exposing the thin films to a nitrogen in a plasma chamber. The exposure to the nitrogen is believed to increase the corrosion resistance of the metallic thin films by causing nitrides to form in a thin surface region. In the preferred embodiment the thin film metals of a magnetic transducer are treated with the nitrogen after being cut from the wafer and lapped. Typical metals used in magnetic transducers are NiMn, FeMn, NiFe, cobalt, CoFe, copper, IrMn and PtMn. The films may be further protected by the addition of prior art protective layers such as carbon.

Method for fabricating a magnetic transducer with a corrosion resistant layer on metallic thin films by nitrogen exposure

A magnetic head including a dual layer induction coil. Following the deposition of a first magnetic pole (P) a first induction coil is fabricated. Following a chemical mechanical polishing (CMP) step a layer of etchable insulation material is deposited followed by the fabrication of a second induction coil etching mask. A reactive ion etch process is then conducted to etch the second induction coil trenches into the second etchable insulation material layer. The etching depth is controlled by the width of the trenches in an aspect ratio dependent etching process step. The second induction coil is next fabricated into the second induction coil trenches, preferably utilizing electrodeposition techniques. Thereafter, an insulation layer is deposited upon the second induction coil, followed by the fabrication of a second magnetic pole (P) upon the insulation layer.

Magnetic head induction coil fabrication method utilizing aspect ratio dependent etching

A method is provided of smoothing the perturbations on a surface, in particular the surface of a magnetic head slider, the method comprising several steps. At least one air-bearing surface to be smoothed is exposed to an ion species generated from a defined source to form a beam of incident radiation. The beam has a linear axis emanating from the source and thus forms an angle of incident radiation with respect to the surface to be smoothed. The at least one surface is smoothed by exposing the surface(s) to be smoothed to the beam of incident radiation, where the angle of incident radiation is less than 90&deg; relative to a vertical axis drawn perpendicular to the surface to be smoothed. To make a corrosion resistant magnetic head slider, the method further comprises coating the smoothed surface with a layer of amorphous carbon.

Method of improving the reliability of magnetic head sensors by ion milling smoothing

Provided is a reactive ion etching (RIE) method for use in altering the flatness of a slider, whereby a slider or row of sliders is placed within a RIE apparatus. The apparatus comprises essentially an electrode within a chamber having an inlet and an outlet. The electrode is controlled by a bias power source. A source power is provided to the chamber to generate the plasma, wherein a gas or gas mixture is first introduced to the chamber and the source power is adjusted to maximize the plasma composition of ions and reactive neutral species. The ions and reactive neutral species are generated from reactive chemical species such as CHF and other F-containing species. An inert gas such as Argon may also be present. Typically, TiC within the Al O matrix of the slider substrate surface is etched at a faster rate than other substrate species.

Method of adjusting the flatness of a slider using selective plasma etching

A magnetic head including a dual layer induction coil. Following the deposition of a first magnetic pole (P ) a first induction coil is fabricated. Following a chemical mechanical polishing (CMP) step a layer of etchable insulation material is deposited followed by the fabrication of a second induction coil etching mask. A reactive ion etch process is then conducted to etch the second induction coil trenches into the second etchable insulation material layer. The etching depth is controlled by the width of the trenches in an aspect ratio dependent etching process step. The second induction coil is next fabricated into the second induction coil trenches, preferably utilizing electrodeposition techniques. Thereafter, an insulation layer is deposited upon the second induction coil, followed by the fabrication of a second magnetic pole (P ) upon the insulation layer.

A method of corrosion susceptibility testing of a magnetic recording head is disclosed. The method includes applying simulated disk corrosion products containing cobalt salts to the recording head. The recording head is then placed in an environmental chamber with elevated temperature and humidity. The resistance of the sensor on the recording head is measured after removal from the chamber and compared with the resistance before placement in the chamber. A significant change in resistance indicates a corrosion failure. This component level testing gives a more accurate indication of the corrosion performance of the recording head when placed in a disk drive.

Method for corrosion susceptibility testing of magnetic heads using simulated disk corrosion products

The invention relates to a method for producing magnetic sliders having a permanent protective coating of carbon over the air bearing surface. The method comprises the steps of: (a) depositing a temporary protective coating on a surface of the slider, the temporary protective coating comprising a layer carbon; (b) depositing a photoresist layer onto the temporary protective coating; (c) imagewise exposing the photoresist layer to radiation; (d) developing the image in the photoresist layer to expose the temporary protective coating; (e) transferring the image through the temporary protective coating and into the slider to form the air bearing pattern in the slider; (f) removing the temporary protective coating using nonreactive plasma; and (g) depositing a permanent protective coating comprising a layer of carbon.

Method for forming the air bearing surface of a slider using nonreactive plasma

The invention relates to a method for producing magnetic sliders having a permanent protective coating of carbon over the air bearing surface. The method comprises the steps of: (a) depositing a protective coating on a surface of the slider, the protective coating comprising an underlayer of carbon and a top layer selected from silicon and titanium; (b) depositing a photoresist layer onto the protective coating; (c) imagewise exposing the photoresist layer to radiation; (d) developing the image in the photoresist layer to expose the protective coating; (e) transferring the image through the protective layer and into the slider to form the air bearing pattern in the slider; and (f) removing the top layer of the protective coating.

Method for forming the air bearing surface of a slider

A rotary plater and method of plating are provided which improve the uniformity of plating across a plating surface of a workpiece. A plating solution distribution device is located in a plating cup between an anode and a cathode in a spaced relationship therebetween and is centered about a vertical axis of the plating cup. A motor is provided for relatively rotating the cathode and the plating solution distribution device with respect to one another. The plating solution distribution device distributes the plating solution over the plating surface at a distribution rate which increases radially outwardly from the vertical axis. With this arrangement the volume of plating solution at the outer periphery of the plating surface is enriched with ions to promote plating uniformity.

Rotary plater with radially distributed plating solution

A contactless method and apparatus for real-time in-situ monitoring of a chemical etching process during etching of at least one wafer in a wet chemical etchant bath are disclosed. The method comprises the steps of providing two conductive electrodes in the wet chemical bath, wherein the two electrodes are proximate to but not in contact with a wafer; monitoring an electrical characteristic between the two electrodes as a function of time in the etchant bath of the at least one wafer, wherein a prescribed change in the electrical characteristic is indicative of a prescribed condition of the etching process; and recording a plurality of values of the electrical characteristic as a function of time during etching. From the plurality of recorded values and corresponding times, instantaneous etch rates, average etch rates, and etching end points may be determined. Such a method and the apparatus therefor are particularly useful in a wet chemical etch station.

Real time measurement of etch rate during a chemical etching process

A contactless method and apparatus for real-time in-situ monitoring of a chemical etching process during etching of at least one wafer in a wet chemical etchant bath are disclosed. The method comprises the steps of providing two conductive electrodes in the wet chemical bath, wherein the two electrodes are proximate to but not in contact with a wafer; monitoring an electrical characteristic between the two electrodes as a function of time in the etchant bath of the at least one wafer, wherein a prescribed change in the electrical characteristic is indicative of a prescribed condition of the etching process; detecting a minimum and maximum value of the electrical characteristic during etching; determining the times of the minimum and maximum values; and comparing the times of the minimum and maximum values to determine a film etching uniformity value. Such a method and the apparatus therefor are particularly useful in a wet chemical etch station, and are useful for film deposition process quality control.

Chemical etch monitor for measuring film etching uniformity during a

A contactless method and apparatus for real-time in-situ monitoring of a chemical etching process for the etching of at least one wafer in a wet chemical etchant bath are disclosed. The method comprises the steps of providing at least two conductive electrodes in the wet chemical bath, wherein the at least two electrodes are proximate to but not in contact with the at least one wafer, and further wherein said two electrodes are positioned on the same side of the wafer; and monitoring an electrical characteristic between the at least two electrodes, wherein a prescribed change in the electrical characteristic is indicative of a prescribed condition of the etching process. Such a method and apparatus are particularly useful in a wet chemical etch station.

Contactless real-time in-situ monitoring of a chemical etching

A contactless method and apparatus for real-time in-situ monitoring of a chemical etching process to minimize overetch of at least one wafer in a wet chemical etchant bath are disclosed. The method comprises the steps of providing two conductive electrodes in the wet chemical bath, wherein the two electrodes are proximate to but not in contact with a wafer; monitoring an electrical characteristic between the two electrodes as a function of time in the etchant bath of the at least one wafer, wherein a prescribed change in the electrical characteristic is indicative of a prescribed condition of the etching process; detecting a minimum and maximum value of the electrical characteristic during etching; determining the times of the minimum and maximum values; and comparing the times of the minimum and maximum values to determine an overetch value. The overetch value may be compared to a desired value to control the etching process. Such a method and the apparatus therefor are particularly useful in a wet chemical etch station.

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San Jose, CA, United States of America

Yiping Hsiao