Abstract: A slider is described with a resistive electro-lapping guide (ELG), which is aligned with a structure in the write head such as the throat height or trailing shield thickness and extends from the lapping region through the ABS and is connected to pads on the surface of the slider. In a second embodiment the ELG is disposed entirely in the section of the slider which will be removed by lapping. Another embodiment of the invention is a system for single slider lapping which simultaneously monitors the resistance of the read sensor or a read head ELG and at least one ELG that is aligned with a structure in the write head. A controller uses the resistance information to implement an algorithm which decides when lapping should be terminated.

Abstract: The invention is a magnetic transducer with separated read and write heads for perpendicular recording. The write head has a trailing shield that extends from the return pole piece toward the main pole piece to form the write gap at the air-bearing surface. One embodiment of the trailing shield is a two part structure with a pedestal and a much smaller tip that confronts the main pole piece at the gap. In one embodiment a sink of non-magnetic, electrically conductive material is disposed in the separation gap between the read head and the flux bearing pole piece. The sink is preferably made of copper and does not extend to the ABS.

Abstract: An embodiment of the invention is a head for perpendicular recording that has a trailing shield and side shields that are connected to the return pole piece by two studs of ferromagnetic material. The studs extend parallel to the track direction and are located a sufficient distance away from the main pole piece to reduce the flux flow from the main pole piece to the studs. Optionally the studs can be recessed behind the air-bearing surface. The preferred embodiment of the invention is a magnetic transducer with separated read and write heads for perpendicular recording.

Abstract: A process for fabricating sliders with one or more sacrificial structures (extensions) that facilitate lapping to create the air-bearing surface (ABS) is described. Prior to separating individual sliders from a wafer, a mask of material that is not removable by deep reactive ion etching (DRIE) is patterned on the surface of the sliders. The mask outlines a sacrificial extension around portions of the magnetic transducer elements that are nearest the predetermined plane which will become the ABS. The sacrificial extension makes the surface of the slider which will be lapped non-planar. The sacrificial extension extends below the predetermined ABS plane. When the sliders are individually separated by DRIE, the shape of the mask including the sacrificial extension is projected down into and along the slider body.

Abstract: An exchange-coupled magnetic structure includes a ferromagnetic layer, a coercive ferrite layer, such as cobalt-ferrite, for biasing the magnetization of the ferromagnetic layer, and an oxide underlayer, such as cobalt-oxide, in proximity to the coercive ferrite layer. The oxide underlayer has a lattice structure of either rock salt or a spinel and exhibits no magnetic moment at room temperature. The underlayer affects the structure of the coercive ferrite layer and therefore its magnetic properties, providing increased coercivity and enhanced thermal stability. As a result, the coercive ferrite layer is thermally stable at much smaller thicknesses than without the underlayer. The exchange-coupled structure is used in spin valve and magnetic tunnel junction magnetoresistive sensors in read heads of magnetic disk drive systems. Because the coercive ferrite layer can be made as thin as 1 nm while remaining thermally stable, the sensor satisfies the narrow gap requirements of high recording density systems.

Abstract: A method of influencing variations in composition of thin films is described. The elemental plasma field distribution in sputtering systems is manipulated by generating a nonuniform electric field along a surface of the substrate to alter the composition by differentially re-sputtering the target elements. The nonuniform electric field is used to modulate the kinetic energy of the ions generated in the plasma which strike the thin film's surface. By applying varying electric potentials at a plurality of points on a conductive surface of a substrate, the electric field across the surface of the substrate can be modulated in a variety of patterns. In the preferred embodiment a radial voltage gradient is applied to a conductive surface of a disk on which a magnetic thin film is being formed to radially modulate the platinum content of the magnetic film.

Abstract: A current-in-the-plane (CIP) giant magnetoresistive (GMR) spin valve sensor has its free layer magnetization stabilized by longitudinal biasing through the use of free layer end-region antiferromagnetic exchange coupling. An antiparallel coupling (APC) layer, such as Ru, is formed on the free layer and a ferromagnetic bias layer is formed on the APC layer. The bias layer is a continuous layer that extends across the entire width of the free layer. The central region of the bias layer is formed of nonmagnetic oxides of one or more of the elements making up the bias layer, with the bias layer end regions remaining ferromagnetic. The oxidized central region of the bias layer defines the central active track-width region of the underlying free layer. The ferromagnetic end regions of the bias layer are antiferromagnetically coupled across the APC layer to the corresponding underlying free layer end regions to provide the longitudinal biasing.

Abstract: A method for sputtering a thin film protective layer with improved durability is disclosed. The method reduces kinetic energy of the ions of the overcoat material during the initial period of deposition to form a buffering interface which reduces the interpenetration of the atoms of the protective layer into the underlying film. In the method of the invention the sputtering of the overcoat preferably begins with zero (or very low) voltage applied to the underlying film resulting in minimal ion implantation in the underlying film. The “high energy” phase of the process begins with increases in the magnitude of the negative bias voltage applied to the underlying film. The higher energy imparted to ions in the plasma result in a denser and harder film being formed over the initial buffer layer. The protective layer preferably comprises carbon and nitrogen.

Abstract: Multiple embodiments of the invention are described which include at least two laminated ferromagnetic layers with differing magnetic anisotropy. The independent magnetic layer farther away from the recording head is selected to have a lower magnetic anisotropy to allow magnetic switching of the multiple magnetic layers to occur at approximately the same head write current even though the recording head field is reduced with increased distance from the head. The improved switching yields improved magnetic recording performance. Laminated magnetic media according to the invention can have a single peak in the normalized DC erase noise vs. head write current plot indicating that the magnetic transitions in the non-slave magnetic layers are written at the same head write current. As a result the magnetic pulse width (PW50) is reduced, overwrite (OW) is improved and media signal-to-noise ratio (SoNR) is improved.

Abstract: A method for burnishing a slider in a disk drive in which the disk is rotated in the opposite or reverse direction from that used to develop the air-bearing and to read and write data is described. Rotating the disk in the reverse direction results in no air-bearing being formed and the slider being in contact with the disk surface. The burnishing removes material over the magnetic transducers in the slider which separate the transducers from the disk resulting in greater sensitivity. Optionally the stopping point for burnishing can be determined by monitoring measurable parameters such as the change in the MR resistance (MRR), i.e., ?MRR/MRR until a selected range is achieved. The invention can be used to remove an overcoat from the air-bearing surface of the slider, remove protruding areas from the slider and to remove debris from the disk surface.

Abstract: A data storage system is described with a system for controlling the amount of lubricant being dispensed from the reservoir using a feedback loop that includes at least one sensor output for a physical parameter inside device such as temperature, humidity and fly-height. In one embodiment the lubricant reservoir housing is equipped with a movable shutter over an aperture in the lubricant reservoir housing. The area of the aperture through which the lubricant vapor can pass is controlled by moving the shutter. In another embodiment the lubricant reservoir housing is supplied with a lubricant diffusion packet such as an effusion cell or diffusion tube containing liquid lubricant. An energy source for the lubricant diffusion packet allows the temperature of the lubricant and, therefore, its vapor pressure, to be increased when the need for additional lubricant is sensed.

Abstract: The applicants disclose a thin film magnetic media structure with a pre-seed layer of CrTiAl. The CrTiAl pre-seed layer presents an amorphous or nanocrystalline structure. The CrTiAl pre-seed layer improves in-plane c-axis orientation while maintaining a good orientation ratio. The pulse transition width (PW50) is narrowed and the soft error rate is improved. The preferred seed layer is RuAl.

Abstract: A thin film structure for a magnetic thin film recording medium including a dual seed layer of RuAl/NiAlB is disclosed. The use of the RuAl/NiAlB structure provides reduced grain size, an increased Mrt orientation ratio (OR), increased SNR and lower PW50 at higher amplitude. The RuAl and NiAlB seed layers each have a B2 crystallographic structure. The RuAl/NiAlB dual seed layer can be used to obtain an underlayer with a preferred in-plane orientation of (200) and a cobalt alloy magnetic film with the preferred in-plane orientation of (11{overscore ( )}20).

Abstract: A thin film magnetic media structure with a bi-layer structure of amorphous chromium titanium (CrTi) followed by an amorphous layer of nickel phosphorus (NiP) is disclosed. After the NiP has been deposited it is exposed to oxygen to form an oxidized surface. Preferably the underlayer is deposited directly onto the oxidized NiP surface. The bi-layer structure of CrTi/NiP promotes excellent in-plane crystallographic orientation in the cobalt alloy magnetic layer(s) and allows an ultra-thin chromium underlayer to be used which provides better control over grain size and distribution. When the CrTi/NiP bi-layer structure is combined with a circumferentially textured substrate, preferably glass, a high Mrt orientation ratio (OR) results.

Abstract: A magnetic transducer including an electrically conductive shield (ECS) which is disposed between the substrate and first magnetic shield is described. The ECS is preferably embedded in an insulating undercoat layer. The ECS is preferably electrically isolated from the magnetic sensor element and is externally connected to a ground available in the disk drive through the arm electronics. Two alternative ways for connecting the ECS to a ground are described. In one embodiment which is only effective with single-ended input type arm electronics, the ECS is connected to a ground through a via to a lead pad for the read head which is connected to the ground of the arm electronics. In a second and more preferred embodiment a separate lead pad is included on the head to allow the ECS to be connected to electronic or case ground when the head is installed in the arm. The extent of the ECS should be sufficiently large to cover the read head portion of the transducer, i.e.

Abstract: A thin film magnetic media structure with a pre-seed layer of CrTi is disclosed. The CrTi pre-seed layer presents an amorphous or nanocrystalline structure. The preferred seed layer is RuAl for use with the CrTi pre-seed layer. The use of the CrTi/RuAl bilayer structure provides superior adhesion to the substrate and resistance to scratching, as well as, excellent coercivity and signal-to-noise ratio (SNR) and reduced cost over the prior art. One embodiment of the invention sputter-deposits a CrTi pre-seed layer and a RuAl seed layer followed by at least one underlayer and at least one magnetic layer on a circumferentially polished substrate structure to achieve an Mrt orientation ratio greater than one. Two methods according to the invention allow the Mrt orientation ratio of the disk to be adjusted or maximized by varying the thickness of the RuAl seed layer and/or altering the atomic percentage of titanium in the pre-seed layer.

Abstract: A magnetic thin film disk for use in a disk drive with a ruthenium-aluminum (RuAl) seed layer with B2 structure followed by a NiAl layer is described. The disk has reduced noise and increased squareness which results in improved recording performance in a disk drive utilizing the disk. The improved disk is formed by first depositing the RuAl seed layer on the substrate then the NiAl layer is deposited onto the NiAl, followed by the other layers required for a magnetic disk such as an underlayer material with a lattice parameter compatible with RuAl such as Cr-alloy, followed by a standard hcp magnetic material. The RuAl seed layer promotes a [100] preferred orientation in the underlayer which in turn promotes a [11{overscore (2)}0] preferred orientation in the magnetic layer.

Abstract: A magnetic transducer (head) according to the invention includes multilayered electrically conductive leads from the magnetic sensor which include a thin tantalum seed layer followed by a thin chromium seed layer which is followed by a thicker rhodium layer. The dual seed layer of the invention significantly improves the conductivity of the rhodium. The Ta/Cr/Rh leads can be used with hard bias structures formed on a PtMn layer without having increased resistance.

Abstract: A method for producing a magnetic transducer with a inductive write head having a multilayer coil with a high aspect ratio and a short yoke is provided. A damascene process is used for two coil layers and a conventional process for the third coil layer. The process of the invention allows a seed layer for the coil to be deposited on the side walls of the trenches for the first and second coil layers. In one embodiment the seed layer for the coil is preceded by an adhesion layer.

Abstract: A method for fabricating a transducer with landing pads without edge fences is described. Preferably an adhesion layer and then the pad layer are deposited in voids in a photoresist. The thickness of the masking layer on the surface of the pad layer should be sufficient to protect pad layer during the subsequent ashing step, but the thickness of the masking material at the sidewalls on the pad layer fences should be thin enough so that the fences are not protected during ashing. After stripping the photoresist material, the structure is ashed preferably by an oxygen-containing plasma. The ashing process, with assistance from mechanical abrasion, removes the fence structures on the pad layer, since the thinner masking layer at the sidewalls provides less protection to the fence structures than is provided to the bulk of the pad layer where the masking layer is thicker.