Abstract: A magnetic head assembly has an open yoke type write head constructed on top of a read head so that the write head can be constructed with a very narrow track width without restraint by the requirements of the read head. The write head has first and second pole piece portions wherein the second pole piece portion has separate front and back layer portions. A coil layer is wrapped around only the first pole piece portion and the back layer portion so that the front layer portion can be constructed separately to provide a narrow track width. Further, in a preferred embodiment the front layer portion has a reduced thickness and a higher magnetic moment than the thickness and magnetic moment of the first pole piece portion and the back layer portion. Still further, in a preferred embodiment the first pole piece portion and the back layer portion are planar due to polarization of underlying layers.

Abstract: A magnetic head for a hard disk drive. The magnetic poles of the head are formed with a NiFe alloy having a graduated composition in which a higher Fe concentration is fabricated proximate the write gap layer between the magnetic poles. Each magnetic pole is fabricated in a single electroplating step in which the duty cycle of the electroplating current is altered during the electroplating operation. Where the duty cycle is greatest the Fe ion concentration is likewise greatest.

Abstract: A slider fabrication assembly and method for making the same are provided. A slider is formed on a substrate. A corrodible component of the slider is exposed to an environment in contact with the slider. A kerf region of the substrate is positioned adjacent to the slider. The kerf region is removable from the slider. A sacrificial anode is embedded in the kerf region and exposed to the environment. The sacrificial anode is electrically coupled to the corrodible component of the slider thereby forming an electrochemical cell. The sacrificial anode is less noble, i.e., more corrodible, than the corrodible slider component, and thus corrodes first. When the kerf region is removed, the corroded sacrificial anode is removed as well.

Abstract: The electroplated components of a magnetic head of the present invention are fabricated utilizing a seed layer that is susceptible to reactive ion etch removal techniques. A preferred seed layer is comprised of tungsten or titanium. Following the electroplating of the components utilizing a fluorine species reactive ion etch process the seed layer is removed, and significantly, the fluorine RIE process creates a gaseous tungsten or titanium fluoride compound removal product. The problem of seed layer redeposition along the sides of the electroplated components is overcome because the gaseous fluoride compound is not redeposited. The present invention also includes an enhanced two part seed layer, where the lower part is tungsten, titanium or tantalum and the upper part is composed of the material that constitutes the component to be electroplated.

Abstract: An low profile inductive write head is provided to improve track definition and head efficiency and to reduce overcoat and pole tip protrusion and cracking caused by thermal expansion. A first insulation layer of an insulation stack enclosing the coil layer is formed of an non-magnetic inorganic insulator material such as aluminum oxide, silicon dioxide or titanium dioxide having a thickness of in the range of 0.2-0.3 microns. The thinner first insulation layer results in a significantly reduced slope of the insulation stack which decreases reflective notching during processing of the second pole tip to improve track definition. Improved thermal conduction properties of the inorganic insulator material improves heat sinking of the write coil reducing overcoat and pole tip protrusion and cracking at the pole tip/write gap layer interface.

Abstract: A magneto-resistive read head having a “parasitic shield” provides an alternative path for currents associated with sparkovers, thus preventing such currents from damaging the read head. The parasitic shield is provided in close proximity to a conventional magnetic shield. The electrical potential of parasitic shield is held essentially equal to the electrical potential of the sensor element. If charges accumulate on the conventional shield, current will flow to the parasitic shield at a lower potential than would be required for current to flow between the conventional shield and the sensor element. Alternatively, conductive spark gap devices are electrically coupled to sensor element leads and to each magnetic shield. Each spark gap device is brought within very close proximity of the substrate to provide an alternative path for charge that builds up between the sensor element and the substrate to be discharged.

Abstract: A slider fabrication assembly and method for making the same are provided. A slider is formed on a substrate. A corrodible component of the slider is exposed to an environment in contact with the slider. A kerf region of the substrate is positioned adjacent to the slider. The kerf region is removable from the slider. A sacrificial anode is embedded in the kerf region and exposed to the environment. The sacrificial anode is electrically coupled to the corrodible component of the slider thereby forming an electrochemical cell. The sacrificial anode is less noble, i.e., more corrodible, than the corrodible slider component, and thus corrodes first. When the kerf region is removed, the corroded sacrificial anode is removed as well.

Abstract: An etch barrier to be used in a photolithograph process is disclosed. A silicon rich etch barrier is deposited on a substrate using a low energy deposition technique. A diamond like carbon layer is deposited on the silicon rich etch barrier. Photoresist is then placed on this etch barrier DLC combination. To form photolithographic features, successive steps of oxygen and flourine reactive ion etching is used.

Abstract: The electroplated components of a magnetic head of the present invention are fabricated utilizing a seed layer that is susceptible to reactive ion etch removal techniques. A preferred seed layer is comprised of tungsten or titanium. Following the electroplating of the components utilizing a fluorine species reactive ion etch process the seed layer is removed, and significantly, the fluorine RIE process creates a gaseous tungsten or titanium fluoride compound removal product. The problem of seed layer redeposition along the sides of the electroplated components is overcome because the gaseous fluoride compound is not redeposited. The present invention also includes an enhanced two part seed layer, where the lower part is tungsten, titanium or tantalum and the upper part is composed of the material that constitutes the component to be electroplated.

Abstract: In the NiFe electroplating method of the present invention, the atomic percent (at. %) composition of Ni and Fe in NiFe electroplated material is controlled by selection of the duty cycle of the electroplating current during the electroplating process. Generally, for a particular electroplating bath, where the electroplating current duty cycle is greatest the NiFe electroplated material has a higher Fe at. %, and where the electroplating current duty cycle is reduced, a lower Fe at. %. Therefore, electroplated NiFe components from a single electroplating bath can have differing NiFe concentrations where the electroplating current duty cycle is altered. Additionally, NiFe components can be electroplated with a graduated or changing Ni and Fe concentration by altering the electroplating current duty cycle during the electroplating process.

Abstract: A thin-film write head employing pole pieces formed of an electroplated body-centered cubic (BCC) nickel-iron alloy with a saturation flux density (BS) of 1.9 to 2.3 T (19 to 23 kG) and an acceptable coercivity (HC) of about 80 to about 160 A/m (1-2 Oe). The iron content of the electroplated nickel-iron alloy is from 64% to 81% by weight. The two-layer pole fabrication process holds magnetic anisotropy and coercivity to useable values while improving saturation flux density and optimizing magnetostriction. This is accomplished by first electroplating a BCC nickel-iron layer onto an underlying seed layer and then annealing the two layers to reduce coercivity to less than about 160 amps/meter and raise magnetization to acceptable levels.

Abstract: A process for electroplating and annealing thin-films of nickel-iron alloys having from 63% to 81% iron content by weight to produce pole pieces having saturation flux density (BS) in the range from 1.9 to 2.3 T (19 to 23 kG) with acceptable magnetic anisotropy and magnetostriction and a coercivity (HC) no higher than 160 A/m (2 Oe). The desired alloy layer properties, including small crystal size and minimal impurity inclusions, can be produced by including higher relative levels of Fe++ ions in the electroplating bath while holding the bath at a lower temperature while plating from a suitable seed layer. The resulting alloy layer adopts a small crystal size (BCC) without significant inclusion of impurities, which advantageously permits annealing to an acceptable HC while retaining the high BS desired.

Abstract: A read head is provided with an N-cycle switch for sequentially shorting and unshorting a sense current circuit of a read head so that the read head will be protected from electrostatic discharges (ESDs) by shorting when the read head is not being tested and unshorted during tests of the read head. The shorting and unshorting switches, which are mounted on or in a slider carrying the read head, are activated by a laser beam.

Abstract: An low profile inductive write head is provided to improve track definition and head efficiency and to reduce overcoat and pole tip protrusion and cracking caused by thermal expansion. A first insulation layer of an insulation stack enclosing the coil layer is formed of an non-magnetic inorganic insulator material such as aluminum oxide, silicon dioxide or titanium dioxide having a thickness of in the range of 0.2-0.3 microns. The thinner first insulation layer results in a significantly reduced slope of the insulation stack which decreases reflective notching during processing of the second pole tip to improve track definition. Improved thermal conduction properties of the inorganic insulator material improves heat sinking of the write coil reducing overcoat and pole tip protrusion and cracking at the pole tip/write gap layer interface.

Abstract: A thermally-assisted magnetic recording disk drive records data by heating a small region of the magnetic layer on the disk to near or above its Curie temperature while a write field is applied by a thin film inductive write head. The thin film inductive write head includes an electrically resistive heater located in the write gap between the pole tips of the write head. The resistive heater is sandwiched between first and second spacer layers that are located between the pole tips of the write head. In a current-perpendicular-to-the plane (CPP) embodiment, the spacer layers are electrically conductive and the pole tips serve as the electrical leads to provide electrical current in a direction generally perpendicular to the layer of resistive heater material. In a current-in-the plane (CIP) embodiment, the spacer layers are formed of insulating material and electrical leads are formed as portions of a film between the spacer layers and in contact with each side of the resistive heater.

Abstract: In the NiFe electroplating method of the present invention, the atomic percent (at. %) composition of Ni and Fe in NiFe electroplated material is controlled by selection of the duty cycle of the electroplating current during the electroplating process. Generally, for a particular electroplating bath, where the electroplating current duty cycle is greatest the NiFe electroplated material has a higher Fe at. %, and where the electroplating current duty cycle is reduced, a lower Fe at. %. Therefore, electroplated NiFe components from a single electroplating bath can have differing NiFe concentrations where the electroplating current duty cycle is altered. Additionally, NiFe components can be electroplated with a graduated or changing Ni and Fe concentration by altering the electroplating current duty cycle during the electroplating process.

Abstract: A magnetic head for a hard disk drive. The magnetic poles of the head are formed with a NiFe alloy having a graduated composition in which a higher Fe concentration is fabricated proximate the write gap layer between the magnetic poles. Each magnetic pole is fabricated in a single electroplating step in which the duty cycle of the electroplating current is altered during the electroplating operation. Where the duty cycle is greatest the Fe ion concentration is likewise greatest.

Abstract: An etch barrier to be used in a photolithograph process is disclosed. A silicon rich etch barrier is deposited on a substrate using a low energy deposition technique. A diamond like carbon layer is deposited on the silicon rich etch barrier. Photoresist is then placed on this etch barrier DLC combination. To form photolithographic features, successive steps of oxygen and flourine reactive ion etching is used.

Abstract: The electroplated components of a magnetic head of the present invention are fabricated utilizing a seed layer that is susceptible to reactive ion etch removal techniques. A preferred seed layer is comprised of tungsten or titanium and it is fabricated in a sputter deposition process. The seed layer is electrically conductive and the electroplated components, such as induction coil members and magnetic poles, are effectively electroplated into photolithographically created photoresist trenches that are fabricated upon the seed layer. Following the electroplating of the components, the photoresist layer is removed utilizing a standard wet chemical process to expose the seed layer. Next, utilizing a fluorine species reactive ion etch process the seed layer is removed, and significantly, the fluorine RIE process creates a gaseous tungsten or titanium fluoride compound removal product.

Abstract: A magneto-resistive read head having a “parasitic shield” in a data storage system provides an alternative path for currents associated with sparkovers, thus preventing such currents from damaging the read head. The parasitic shield is provided in close proximity to a conventional magnetic shield. The electrical potential of parasitic shield is held essentially equal to the electrical potential of the sensor element. If charges accumulate on the conventional shield, current will flow to the parasitic shield at a lower potential than would be required for current to flow between the conventional shield and the sensor element. Alternatively, conductive spark gap devices are electrically coupled to sensor element leads and to each magnetic shield. Each spark gap device is brought within very close proximity of the substrate to provide an alternative path for charge that builds up between the sensor element and the substrate to be discharged.