Abstract: A read head has a flux guide layer that is immediately adjacent (abuts) the back edge of a read sensor. The flux guide layer is made of a high resistance soft magnetic material that conducts magnetic flux from the back edge of the read sensor so that the magnetic response at the back edge of the read sensor is significantly higher than zero. This increases the efficiency of the read sensor. The material for the flux guide layer is A-B-C where A is selected from the group Fe and Co, B is selected from the group Hf, Y, Ta and Zr and C is selected from the group O and N. In a preferred embodiment A-B-C is Fe—Hf—O and the Ms? of the flux guide layer is greater than 50 times the Ms? of the read sensor layer where the read sensor layer is NiFe, Ms is saturation magnetization and ? is resistivity. Because of the flux guides high resistance current shunting losses are nearly eliminated.

Abstract: A semiconductor slider including an integral spin valve transistor (SVT) having a read width of 250 nm or less disposed on a monolithic semiconductor substrate, useful in magnetic data storage applications. The monolithic slider may also include other magnetic and semiconductor transistor structures and is fabricated in a single process using standard thin-film processing steps. The SVT includes a sensor stack having a top surface and including a first ferromagnetic (FM) layer in contact with and forming a Schottky barrier at the monolithic semiconductor substrate, a FM shield layer disposed over the sensor stack and in electrical contact with the top surface thereof, a SVT emitter terminal coupled to the FM shield, a SVT collector terminal coupled to the substrate and a SVT base terminal coupled to the first FM layer. The sensor stack may include a spin valve (SV) stack or a tunnel valve (TV) stack, for example.

Abstract: A spin valve sensor in a read head has a spacer layer which is located between a self-pinned AP pinned layer structure and a free layer structure. The free layer structure is longitudinally stabilized by first and second hard bias layers which abut first and second side surfaces of the spin valve sensor. The AP pinned layer structure has an antiparallel coupling layer (APC) which is located between first and second AP pinned layers (AP1) and (AP2). The invention employs a preferential setting of the magnetic moments of the AP pinned layers by applying a field at an acute angle to the head surface in a plane parallel to the major planes of the layers of the sensor. The preferential setting sets a proper polarity of each AP pinned layer, which polarity conforms to processing circuitry employed with the spin valve sensor.

Abstract: A method of making a magnetic head assembly wherein the magnetic head assembly has a write head with a pole tip includes the steps of forming a shaping layer on an underlying layer wherein the shaping layer has a side surface and a top surface, ion beam sputter depositing a ferromagnetic material layer on the underlying layer and on the side and top surfaces of the shaping layer and removing first and second portions of the ferromagnetic material layer from the underlying layer and the top surface of the shaping layer, respectively, leaving a remaining portion of the ferromagnetic material layer on the side surface of the shaping layer which is the aforementioned pole tip.

Abstract: A spin valve sensor includes an antiparallel (AP) pinned layer structure which is self-pinned without the assistance of an antiferromagnetic (AFM) pinning layer. A free layer of the spin valve sensor has first and second wing portions which extend laterally beyond a track width of the spin valve sensor and are exchange coupled to first and second AFM pinning layers. Magnetic moments of the wing portions of the free layer are pinned parallel to the ABS and parallel to major planes of the layers of the sensor for magnetically stabilizing the central portion of the free layer which is located within the track width.

Abstract: A spin valve sensor has an antiparallel (AP) pinned layer structure which has ferromagnetic first and second AP pinned layers that are separated by an antiparallel coupling layer. The first and second AP pinned layers are self-pinned antiparallel with respect to one another without the assistance of an antiferromagnetic (AFM) pinning layer. First and second hard bias layers interface first and second side surfaces of the spin valve sensor and the sensor has a central portion that extends between the first and second hard bias layers. First and second lead layers overlay the first and second hard bias layers and overlay first and second end portions of the central portion so that a distance between the first and second lead layers defines a track width that is less than a distance between the first and second hard bias layers.

Abstract: First, second and third pole tip components of a write head are formed with the second pole tip located between the first and third components and a write gap layer located between the first and second pole tip components. The second pole tip is formed with a width that defines a track width of the write head. The third pole tip component is formed with top and bottom surfaces wherein the bottom surface interfaces a top surface of the second pole tip component and has a width equal to the track width and wherein the top surface of the third pole tip has a width greater than the track width.

Abstract: A spin valve sensor has an antiparallel (AP) pinned layer structure which has ferromagnetic first and second AP pinned layers that are separated by an antiparallel coupling layer. The first and second AP pinned layers are self-pinned antiparallel with respect to one another without the assistance of an antiferromagnetic (AFM) pinning layer. The spin valve sensor further includes an in-stack longitudinal biasing layer structure which is magnetostatically coupled to the free layer for longitudinally biasing a magnetic moment of the free layer parallel to an air bearing surface and parallel to major planes of the layers of the sensor. The only AFM pinning layer employed is in the biasing layer structure so that when the magnetic spins of the AFM pinning layer are set the orientations of the magnetic moments of the AP pinned layer structure are not disturbed.

Abstract: A magnetic tunnel junction (MTJ) sensor in which the free layer longitudinal biasing elements are coupled, without insulation, to the free layer outside of the MTJ stack to provide reliable non-shunting MTJ free layer stabilization without extremely thin dielectric layers. In one embodiment, hard magnetic (HM) layers are disposed in contact with the free layer outside of and separated from the MTJ stack active region by a thick dielectric layer. In another embodiment, antiferromagnetic (AFM) bias layers are disposed in contact with the free layer outside of and separated from the MTJ stack active region by a thick dielectric layer. In other embodiments, nonconductive HM layers are disposed either in contact with the free layer outside of the MTJ stack active region and/or in abutting contact with the MTJ stack active region.

Abstract: A magnetic head assembly includes a read head with a current perpendicular to the planes (CPP) sensor. The CPP sensor includes an AP pinned layer structure, a free layer and a spacer layer which is located between the free layer and the AP pinned layer structure. An in-stack longitudinal biasing structure for longitudinally biasing the free layer includes a pinned layer, an AFM pinning layer for pinning the pinned layer and a chromium spacer layer which is located between the pinned layer and the free layer. The free layer includes first and second free films with the first free film being iron and interfacing the spacer layer. The second free film may be nickel iron for imparting magnetic softness to the first free film. The pinned layer and a second AP pinned layer of the free layer structure may also be iron. The iron content of the layers in the sensor and the chromium spacer layer significantly increase the magnetoresistive coefficient dr/R of the CPP sensor.

Abstract: A write head has a variable throat height wherein the throat height is dependent upon the frequency of operation of the write head. At high frequency operation the throat height is small and at low frequency operation the throat height is large. The write head writes hard into a circular track of a rotating magnetic disk at all frequencies but not overly hard at low frequencies thereby avoiding excessive erase bands and adjacent track interference (ATI) on each side of the track being written.

Abstract: A method makes a spin valve sensor of a magnetic read head which includes the steps of forming a ferromagnetic pinned layer structure that has a magnetic moment, forming a pinning layer exchange coupled to the pinned layer structure for pinning the magnetic moment of the pinned layer structure, forming a free layer structure, forming a nonmagnetic electrically conductive spacer layer between the free layer and the pinned layer structure and the forming of the free layer structure including the step of sputter depositing at least a first free layer composed of cobalt iron directly on the spacer layer in a nitrogen atmosphere.

Abstract: A bilayer mask employed for lift off has a top strip which bridges between first and second bilayer portions and is completely undercut so that when one or more materials is sputter deposited the materials do not form fences abutting recessed edges of a bottom layer in undercuts below a top layer. Sacrificial protective layers are formed on a sensor and lead layers for protecting these components while overlapping portions of these materials on the top of the sensor formed during deposition can be removed by ion beam sputtering, after which the sacrificial protective layers can be removed by ion milling or reactive ion etching.

Abstract: A magnetic head assembly includes a first lead that is electrically connected to a CPP sensor for conducting a current through the sensor perpendicular to major planes of the layers of the sensor. A second lead extends from a stripe height of the sensor into the head assembly. A nonmagnetic electrically conductive bias layer, which has major planes that are parallel to the major planes of the sensor, is electrically connected to the sensor and the second lead so that when the current flows through the bias layer parallel to the major planes of the bias layer and perpendicular to a head surface of the CPP sensor a free layer of the sensor is biased by the bias layer.

Abstract: A method of making a dual spin valve sensor includes the steps of forming first and second pinned layer structures, forming antiferromagnetic first and second pinning layers exchange coupled to the first and second pinned layer structures, forming an antiparallel (AP) coupled free layer structure between the first and second pinned layer structures, forming nonmagnetic conductive first and second spacer layers between the AP coupled free layer structure and the first and second pinned layer structures respectively, and a making of the AP coupled free layer structure includes the steps of forming ferromagnetic first, second and third antiparallel (AP) coupled free layers and forming a first antiparallel coupling layer between the first and second AP coupled free layers and a second antiparallel coupling layer between the second and third AP coupled free layers.

Abstract: A specified amount of N2O or N2 is employed in a process gas of a DC magnetron for sputter depositing single or laminated films of NiFeCo—O—N or NiFeCo—N with a high uniaxial anisotropy HK after annealing these films along their hard axes. The films can be used for shield layers and/or pole piece layers in a magnetic head.

Abstract: A method of making a magnetic head, which has an air bearing surface (ABS) and a back gap (BG), comprising the steps of: forming a second pole tip of a second pole piece with a top surface and a bottom surface at an ABS site for said ABS; the top surface of the second pole tip having a write region located at the ABS site and a stitch region which is recessed in its entirety from the ABS site toward said back gap; depositing a protective sacrificial layer on the write region of the second pole tip; removing said sacrificial layer from only the stitch region of the second pole tip; and forming a second pole piece yoke of a second pole piece magnetically connected to the stitch region of the second pole tip.

Abstract: A nonlinear transition shift (NLTS) measurement procedure for read/write heads employing a giant magnetoresistive (GMR) merged heads. The method of this invention includes the pulse-shape distortion effects on recording nonlinearity, which can significantly affect the existing theoretical formulae for calculating nonlinearity correction factor from measured partial erasure values, and second-order approximation of equation of NLTS and nonlinearity correction factor. Transition broadening effects (TBE) and partial erasure (PE) are incorporated in the NLTS measurement procedure to permit accurate isolation of the NLTS from the unrelated TBE/PE and GMR nonlinear transfer characteristic (NTC). First, a fifth harmonic elimination (5HE) test is performed at bit period T to measure a first nonlinearity value X.

Abstract: The first and second side surfaces of either a bottom spin valve sensor or a top spin valve sensor are notched so as to enable a reduction in the magnetoresistive coefficient of side portions of the sensor beyond the track width region thereby minimizing side reading by the sensor. The first and second notches of the spin valve sensor are then filled with layers in various embodiments of the invention to complete the spin valve sensor.

Abstract: A spin valve sensor includes a free layer structure which is located between first and second spacer layers and the first and second spacer layers are located between first and second AP pinned layer structures. Each of the AP pinned layer structures has first and second AP pinned layers with the first AP pinned layer of the first AP pinned layer structure interfacing the first spacer layer and the first AP pinned layer of the second AP pinned layer structure interfacing the second spacer layer. The magnetic thickness of each of the first AP pinned layers is either greater or less than the magnetic thickness of either of the second AP pinned layers of the first and second AP pinned layer structures so that a magnetic field oriented perpendicular to an air bearing surface (ABS) of the sensor sets the magnetic moments of the first and second AP pinned layer structures in-phase so that changes in resistances of the sensor upon rotation of a magnetic moment of the free layer structure is additive.