Abstract: A tunnel junction read head is provided with free and pinned layers which are recessed from the ABS with the free layer being connected to a flux guide which extends the free layer to the ABS for conducting signal fields to the free layer from a rotating magnetic disk. With this arrangement the typical narrow spacing between the free and pinned layers at the ABS is obviated so that upon lapping of the read head during its construction, conductive material will not be smeared between these layers so as to cause shorting therebetween.

Abstract: A read head is provided with a combined second read gap and pinning layer which pins a pinned layer structure of a top spin valve sensor. The second read gap layer is at least partially composed of alpha ferric oxide (&agr;Fe2O3) which pins the pinned layer by coercivity. The second read gap layer defines the track width of the read head and its alpha ferric oxide (&agr;Fe2O3) composition provides specular reflection of conduction electrons in the spin valve sensor.

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 read head has first and second leads that are shorted to first and second shields so that the first and second shields function as lead layer extensions for the first and second leads. This permits a second read gap layer to be thinner so that a free layer structure of a spin valve sensor is located closer to a second shield layer. This increases a net imaging current field HIM which can be employed for counterbalancing a strong sense current field HI due to conductive layers on one side of the free layer structure. Connection of the first and second lead layers to the first and second shield layers promotes heat dissipation from the first and second lead layers and a thinner second read gap layer promotes linear read density of the head.

Abstract: A single-sided, notched write head is provided for writing narrow erase band servo tracks as well as a double-notched write head, and for writing data tracks better than a double-notched write head. The single-sided, notched write head writes a narrow erase band on the notched side and a wide erase band on the unnotched side. In one embodiment, only one side of the first pole piece layer is notched, and in another embodiment a first side of the first pole piece layer is notched more than a second side. By writing servo tracks only a fraction of the track width of the write head, a wide erase band region is overwritten so that a narrow erase band is on each side of the servo track. Data tracks are written with a narrow erase band on one side and a wide erase band on the other side. The wide erase band on one side of the data track allows more flexibility in spacing the read head from adjacent tracks.

Abstract: A method of making rhodium (Rh) lead layers for a read sensor comprises a first step of obliquely ion beam sputtering the rhodium (Rh) lead layer followed by a second step of annealing. This method results in rhodium (Rh) lead layers which have reduced stress and less resistance, making them highly desirable for lead layers of a sensor in a read head.

Abstract: A top spin valve sensor includes an iridium manganese (IrMn) pinning layer which has been formed by ion beam sputter deposition. The magnetoresistive coefficient of the spin valve sensor is increased by employing an iridium manganese oxide (IrMnO) seed layer between a free layer of the spin valve sensor and a first read gap layer of the read head. The free layer is preferably a nickel iron free film located between first and second cobalt iron (CoFe) free films.

Abstract: A method of making a magnetic head that has a read head with a track width includes the steps of depositing a read track width defining material layer on a read sensor material layer; forming a bi-layer photoresist mask on the read track width defining material layer that masks a read track width defining layer portion of the read track width defining material layer; removing by reactive ion etching (RIE) a portion of the read track width defining material layer not masked by the photoresist mask to form the read track width defining layer portion with exposed first and second side edges that are spaced apart a distance equal to the track width; removing by ion milling a first portion of the read sensor material layer not masked by the read track width defining layer portion to form a second portion of the read sensor material layer with exposed first and second side edges that have a width equal to the track width; depositing hard bias and lead material layers on the photoresist mask in contact with the firs

Abstract: A pinning layer structure is provided for a spin valve sensor of a read head which has a reactively deposited nickel oxide first film which underlies a reactively sputter deposited second film of iron oxide (Fe2O3) or (Fe3O4). In the preferred embodiment the pinning layer is composed of cobalt (Co) or cobalt iron (CoFe) which is exchange coupled to the iron oxide (Fe2O3) or (Fe3O4) second film of the pinning layer. This structure results in an improved magnetoresistive coefficient (dr/R) which is substantially maintained after annealing so that the magnetic head has good thermal stability when subjected to high temperatures in the presence of a field that is antiparallel to the pinned orientation of the magnetic moment of the pinned layer.

Abstract: The present invention extends the high resistance lead layers of a read head straight back into the head from each of the first and second edges of the read sensor. This lessens the length of each of the high resistance lead layers so that they do not have to be made thicker to satisfy resistance requirements. Accordingly, a lateral width of each high resistance lead portion along the ABS and a thickness thereof are chosen so as to minimize the thickness while yet satisfying the resistance requirements. Further, a method of making the first and second lead layers is provided that minimizes the thickness of the high resistance lead layers. Instead of constructing the high resistance lead layers first, the present method constructs the high resistance lead layers last so that the high resistance lead layers are not altered by subsequent processing steps.

Abstract: A free layer of an AP pinned spin valve sensor can be properly biased when the pinning layer is metallic and no gap offset is provided by counterbalancing a net demagnetizing field HD and a net sense current field HI by a ferromagnetic coupling field HF and a demagnetizing field from a biasing layer HB. The biasing layer is composed of a high resistance material which is preferably cobalt iron niobium (CoFeNb) or cobalt iron niobium hafnium (CoFeNbHf). A thickness of a copper spacer layer is selected so that the ferromagnetic coupling field HF is either positive or negative, depending upon the direction of the sense current field IS conducted through the sensor and the thicknesses of first and second AP pinned layers of an AP pinned layer structure are selected so that the net demagnetizing field HD supports the net sense current field HI.

Abstract: A method employs an RF magnetron sputtering system under specific process conditions for making shield and pole piece ferromagnetic layers of a read write magnetic head wherein the magnetic anisotropy HK of the ferromagnetic layers is substantially maintained without easy axes switching when annealed along their hard axes in the presence of a magnetic field (hard axis annealing).

Abstract: A read head includes a spin valve sensor which is located between first and second read gap layers and the first and second read gap layers are located between first and second shield layers. The spin valve sensor includes a free layer, an antiparallel (AP) pinned layer structure, a pinning layer exchange coupled to the AP pinned layer structure for pinning a magnetic moment of the AP pinned layer structure, a nonmagnetic conductive spacer layer located between the free layer and the AP pinned layer structure wherein the free layer includes a cobalt based layer that interfaces the spacer layer. The AP pinned layer structure includes an AP coupling layer which is located between first and second AP pinned layers wherein the second AP pinned layer is thicker than the first AP pinned layer. A distance from a center of the free layer to one of the first and second shield layers is greater than a distance from the center of the free layer to the other of the first and second shield layers.

Abstract: A specular reflector film of iron oxide is located between ferromagnetic first and second pinned films in a pinned layer for reflecting conduction electrons back for spin dependent scattering for improving the magnetoresistive coefficient of a spin valve sensor. The specular reflector film is preferably &ggr;Fe2O3 since this material is a magnetic phase of iron oxide and will contribute to the magnetic moment of the pinned layer. In a preferred embodiment a dual spin valve sensor is employed wherein a pinned layer with a specular reflector film is located on each side of a free layer structure for reflecting conduction electrons from both sides of the free layer structure. Still further, it is preferred that each pinned layer be an antiparallel (AP) pinned layer structure with a specular reflector film embedded in one of the AP pinned layers of each AP pinned layer structure.

Abstract: A seed layer structure, which is provided for a platinum manganese (PtMn) pinning layer in a spin valve sensor, includes first, second and third seed layers wherein the first seed layer is aluminum oxide (Al2O3), the second seed layer is nickel manganese oxide (NiMnO) the third seed layer is tantalum (Ta). The seed layer structure increases the pinning and exchange coupling fields between the pinning layer and a pinned layer, improves recovery of the magnetic moment of the pinned layer to its original orientation after being subjected to an applied field in the presence of heat and improves predictability of performance of magnetic reads constructed on different wafers.

Abstract: A multilayered free layer structure is provided for a spin valve sensor or a tunnel junction sensor wherein the net uniaxial anisotropy (HK) of the free layer structure is low, even though some of the layers of the free layer structure have a high uniaxial anisotropy. In a preferred embodiment this is accomplished by orienting the easy axes of the high uniaxial anisotropy layers perpendicular with respect to one another so that their uniaxial anisotropies counterbalance one another leaving a low net uniaxial anisotropy which may be simply the uniaxial anisotropy of a low uniaxial anisotropy layer in the free layer structure.

Abstract: A method prepares the top exposed surface of a pinning layer after its sputter deposition for an improved exchange coupling with a sputter deposited pinned layer even though the top surface of the pinning layer has been degraded by exposure to the atmosphere. In a preferred method the relatively thick pinning layer is sputter deposited in a first chamber which has a high sputtering rate and is transferred to a second sputtering chamber where the pinned layer, as well as other layers of a spin valve sensor, are sputter deposited. After transfer to the second sputtering chamber the top surface of the nickel oxide (NiO) pinning layer is sputter etched and a thin layer of nickel oxide (NiO) is sputter deposited thereon followed by sputter deposition of the pinned layer. In a preferred embodiment the thickness of the nickel oxide (NiO) pinning layer portion sputter deposited in the second chamber is approximately 40 Å.

Abstract: A spin valve sensor of a read head has a platinum manganese (PtMn) pinning layer that pins a magnetic moment of an antiparallel (AP) pinned layer structure. The pinned layer structure has a first AP pinned layer exchange coupled to the pinning layer so that the magnetic moment of the first AP pinned layer is pinned in a first direction and has a second AP pinned layer that has a magnetic moment pinned in a second direction antiparallel to the first direction. A free layer structure of the spin valve sensor is located asymmetrically between first and second shield layers so that when a sense current is conducted through the sensor a net image current field is executed on the free layer structure by the shield layers.

Abstract: A method is provided for making a well-defined, highly-predictable chevron type MR sensor for a read head. A first material is selected for a first gap layer. A selected second material is deposited on the first gap layer followed by a resist frame that has elongated openings exposing elongated top portions of the first gap layer that extend at an acute angle to a head surface of the read head. A selected reactive ion etch (RIE) is employed to etch away the exposed portions of the second material layer down to the first material of the first gap layer. The material of the second material layer is chosen to be etched by the RIE while the material of the first gap layer is chosen not to be etched by the RIE. An example is Al2O3 for the first gap layer, SiO2 for the second material layer and a RIE that is fluorine based. The resist frame is removed leaving elongated strips of the second material layer extending at the aforementioned angle to the head surface.

Abstract: A free layer structure is provided with a first layer of cobalt iron boron (CoFeB) for improving soft magnetic properties of the free layer structure in a top spin valve sensor by decreased uniaxial anisotropy HK, easy axis coercivity HC and hard axis coercivity HCK of the free layer structure. The free layer structure also includes a second layer of nickel iron based material and a third layer of cobalt based material disposed adjacent a nonmagnetic conductive spacer layer of a spin valve sensor.