Abstract: A write head has a second pole tip layer, a coil layer and a write coil insulation layer that are planarized at their top surfaces. A thin top insulation layer insulates the top of the coil layer from a yoke portion of the second pole piece which is connected to the second pole tip layer in the pole tip region and connected to a first pole piece layer in a back gap region. In a preferred embodiment the write gap layer extends throughout the yoke region and provides the only insulation between the first pole piece layer and the coil layer. Further, it is preferred that the write coil insulation layer be an inorganic material such as silicon dioxide (SiO2). Several embodiments of the write head are provided along with novel methods of making.

Abstract: One aspect of the present invention provides a horizontal component of a ferromagnetic coupling field on the free layer of a spin valve sensor in the same direction as a longitudinal hard biasing field for magnetically stabilizing the free layer. A second aspect of the present invention provides a sense current field in the same direction as a ferromagnetic coupling field on a free layer for promoting magnetic stabilization of the free layer. A third aspect of the present invention is a combination of the first and second aspects of the invention wherein a horizontal component of the ferromagnetic coupling field is in the same direction as a longitudinal hard biasing field and a sense current field is in the same direction as a vertical component of the ferromagnetic coupling field on the free layer.

Abstract: A process for resetting or initially establishing the magnetic orientation of one or more spin valves in a magnetoresistive read head with improved robustness. The spin valve includes subcomponents such as an antiferromagnetic layer, a ferromagnetic pinned layer, a conductive layer, a free layer, and a hard bias layer. A first external magnetic field is first applied to the spin valve sensor, this field having a first orientation relative to the spin valve sensor. During application of the first external magnetic field, a pulse of electrical current is directed through the spin valve sensor in a first direction, preferably parallel to the magnetic orientation of the external field. The current waveform brings the antiferromagnetic layer of the spin valve past its blocking temperature, freeing its magnetic orientation. The first external field exerts a robust bias upon the antiferromagnetic layer in the desired direction.

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.

Abstract: A simple pinned layer or an antiparallel (AP) pinned structure employs a cobalt niobium (CoNb) based layer or film for increasing the resistance of the pinned structure while maintaining a high magnetization (MS). The cobalt niobium (CoNb) based material has sufficient niobium (Nb) to make the material amorphous for increasing the resistance. With this arrangement, less sense current IS is conducted through the pinned structure which increases signals detected by the spin valve sensor as well decreasing the sense current field on the free layer of the spin valve sensor.

Abstract: A spin valve sensor includes an antiparallel (AP) pinned layer that has first and second ferromagnetic layers separated by a thin coupling layer. The first ferromagnetic layer is exchange coupled to an antiferromagnetic pinning layer so that its magnetic moment is oriented in a first direction and the second ferromagnetic layer is exchange coupled to the first ferromagnetic layer with its magnetic moment oriented in a second direction that is antiparallel to the first direction. In the preferred embodiment the first ferromagnetic layer is cobalt iron niobium hafnium (CoFeNbHf) and the second ferromagnetic layer is cobalt (Co). With this arrangement the first ferromagnetic layer reduces current shunting and has a high coercivity so as to stabilize the pinning of the pinned layer. The cobalt (Co) of the second ferromagnetic layer enhances the spin valve effect by being adjacent to a nonmagnetic electrically conductive spacer layer which, in turn, is adjacent to a ferromagnetic free layer.

Abstract: A spin valve sensor includes an antiparallel (AP) pinned layer that has first and second ferromagnetic layers separated by a thin coupling layer. The first ferromagnetic layer is exchange coupled to an antiferromagnetic pinning layer so that its magnetic moment is oriented in a first direction and the second ferromagnetic layer is exchange coupled to the first ferromagnetic layer with its magnetic moment oriented in a second direction that is antiparallel to the first direction. In the preferred embodiment the first ferromagnetic layer is cobalt iron niobium hafnium (CoFeNbHf) and the second ferromagnetic layer is cobalt (Co). With this arrangement the first ferromagnetic layer reduces current shunting and has a high coercivity so as to stabilize the pinning of the pinned layer. The cobalt (Co) of the second ferromagnetic layer enhances the spin valve effect by being adjacent to a nonmagnetic electrically conductive spacer layer which, in turn, is adjacent to a ferromagnetic free layer.

Abstract: The present invention provides a merged magnetic head and method of making wherein a write portion of the magnetic head is constructed before the read head portion and the first pole tip of the write head defines the track width and zero throat height of the magnetic head. During construction, each insulation layer of an insulation stack is planarized with components of a partially completed first pole piece, thereby promoting highly effective construction of one or more coil layers and the first pole tip of the write head. The insulation stack is recessed with respect to the top surface of the first pole tip so that the insulation stack has substantially no impact on photoresist patterning of the first pole tip. Insulation layers of the stack extend into the field beyond side edges of the first pole piece layer so as to provide planar support for the one or more coil layers.

Abstract: In the present invention a second pole yoke component of a second pole piece is connected (stitched) to a small top surface of a second pole tip component of the second pole piece as well as to a back edge and first and second side edges of the second pole tip component. The extra stitching at the back and side edges provides the required magnetic coupling between the components for transferring flux to and from a second pole tip at an air bearing surface. This arrangement shortens the length of the top stitched area so that one or more coil layers in an insulation stack can be located closer to the ABS for increasing the data rate of the head. Further, this arrangement reduces the amount of material of the second pole piece layer in close proximity to the first pole piece layer so as to minimize flux leakage therebetween.

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 planarization of underlying layers.

Abstract: A spin valve sensor includes an antiparallel (AP) pinned layer that has first and second ferromagnetic layers separated by a thin coupling layer. The first ferromagnetic layer is exchange coupled to an antiferromagnetic pinning layer so that its magnetic moment is oriented in a first direction and the second ferromagnetic layer is exchange coupled to the first ferromagnetic layer with its magnetic moment oriented in a second direction that is antiparallel to the first direction. In the preferred embodiment the first ferromagnetic layer is cobalt iron niobium hafnium (CoFeNbHf) and the second ferromagnetic layer is cobalt (Co). With this arrangement the first ferromagnetic layer reduces current shunting and has a high coercivity so as to stabilize the pinning of the pinned layer. The cobalt (Co) of the second ferromagnetic layer enhances the spin valve effect by being adjacent to a nonmagnetic electrically conductive spacer layer which, in turn, is adjacent to a ferromagnetic free layer.

Abstract: An apparatus and method of making is disclosed for a combination read/write head having improved topography. The disclosed read/write head combines a magnetoresistive (MR) read head with an inductive magnetic write head. The head is planarized at a second shield layer with a planarization layer such that pads and leads connecting the pads to the MR sensor and coil are on a planar surface of the planaritzation layer. This planarization layer allows first and second shield layers to be optimized for the MR sensor to be used and also separates the pads and leads from the substrate. The combination head has first and second shield layers formed on a substrate, the shield layers being separated by a read gap. A magnetoresistive (MR) sensor and MR leads are located in the read gap. The planarization layer is then formed on the substrate, surrounding the first and second shield layers creating a planar surface that is coplanar with a top surface of the second shield layer.

Abstract: A method, devices, and an article of manufacture for reducing magnetic instability in a magnetoresistive read head of a combined read-write head after writing data onto a magnetic storage medium. The last write pulse polarity that results in the least amount of magnetic instability in the read head is determined, and is referred to as the designated polarity. Then, after a set of write pulses is written, it is determined whether the last write pulse has the designated polarity. If the last write pulse does not have the designated polarity, then an additional write pulse with the designated polarity is written. Thus, the last write pulse before a read always has the designated polarity, thereby reducing the magnetic instability of the read head, and consequently improving read head performance.

Abstract: A method of making a keeper layer for a spin valve sensor sputter deposits a layer of cobalt iron niobium hafnium (CoFeNbHf) in the presence of a first magnetic field that is in a first direction, the CoFeNbHf keeper layer is then first annealed in the presence of a second field that is in a second direction and the keeper layer is then subsequently second annealed in the presence of a third field that is in a third direction. The first direction is preferably perpendicular to an air bearing surface of a read head employing the spin valve sensor and the third direction is preferably parallel to the first direction. The second direction is preferably perpendicular to the first direction. This method of making significantly reduces the intrinsic anisotropy (HK) of the keeper layer and also stabilizes the magnetic moment of the keeper layer in a direction which is perpendicular to the ABS.

Abstract: A specular reflector structure including one or more layers is located between a free layer structure and a keeper layer for reflecting conduction electrons toward the free layer so as to increase the magnetoresistive coefficient (dr/R) of the spin valve sensor. In the preferred embodiment the specular reflector structure includes a first specular reflector layer of silver (Ag) and a second specular reflector layer of copper (Cu) with the first specular reflector layer interfacing the keeper layer and the second specular reflector layer interfacing the free layer.

Abstract: A seed layer is provided for a pinning layer which increases the pinning field HPIN between a pinning layer and a pinned layer of a spin valve sensor. In an example the seed layer structure included a first seed layer of cobalt iron boron (CoFeB), a second seed layer of nickel manganese oxide (NiMnO) and a third seed layer of aluminum oxide (Al2O3) with the first seed layer interfacing the pinning layer and the second seed layer being located between the first and third seed layers. A pinning field between the pinning and pinned layers was 600 Oe and the magnetoresistive coefficient of the spin valve sensor was 8.8%. The pinned layer can be a single pinned layer or an antiparallel (AP) pinned layer structure. If the pinned layer structure is a single pinned layer the cobalt iron boron (CoFeB) first seed layer provides a second significant function of at least partially counterbalancing the demagnetizing field from the pinned layer.

Abstract: A method constructs first and second seed layers of a seed layer structure in-situ for a top spin valve sensor for increasing magnetoresistive coefficient dr/R of the sensor, reducing a ferromagnetic coupling field HFC between pinned and free layers of the sensor and reducing coercivity HC of the free layer. The first layer, which is aluminum oxide (Al2O3), is ion beam sputter deposited on a first shield layer in a sputtering chamber under a specified pressure. The second seed layer, which is nickel oxide based, is deposited on the first seed layer by ion beam sputter deposition without breaking the vacuum of the chamber. The free layer is then directly deposited on the second seed layer followed by formation of the remainder of the layers of the spin valve sensor.

Abstract: A dielectric protection layer is formed on the top and first and second side walls of a second pole tip portion of a second pole piece layer for preventing alteration of the track width of the second pole tip portion during subsequent fabrication of metallic components of the write head, such as a write coil, terminal leads to a read sensor and the write coil and studs to the terminal leads.

Abstract: A method forms an aluminum oxide (Al2O3) barrier layer for a tunnel junction sensor. A wafer substrate and an aluminum (Al) target are provided in a sputtering chamber which may have first and second ion beam guns. The first ion beam gun ionizes a noble gas which causes the aluminum target to sputter aluminum atoms onto the wafer substrate. Simultaneously with depositing the aluminum atoms on the wafer substrate the second ion beam gun is employed for providing ionized oxygen which is disseminated within the chamber and reacts with the aluminum atoms on the wafer substrate to form the aluminum oxide barrier layer. Optionally, the second gun may be omitted and oxygen (O2) gas introduced into the chamber through an inlet.

Abstract: A spin valve sensor has a pinned layer structure that has a net positive stress induced uniaxial anisotropy that promotes a pinning of the pinned layer structure in a pinned direction for stabilizing the pinning of the pinned layer structure at high temperatures near to a blocking temperature of a pinning layer which is exchange coupled to the pinned layer.