Abstract: A process for reactive ion etching or ion milling of an air bearing slider comprises the steps of mechanical alignment of unetched slider rows with active transducer devices onto an alignment fixture; positioning a layer of thermally conductive adhesive between the rows and a substrate; heating the adhesive through the substrate such that the adhesive bonds the rows to the substrate while encapsulating the rows; removing the alignment fixture; patterning and etching the exposed planarized slider surfaces; stripping the resist and cutting the rows into individual sliders while still bonded to the substrate; stripping the adhesive with an organic solvent. This process increases tolerance to manufacturing variability, minimizes damage and contamination of the transducer devices, and decreases the cycle time and production costs.

Abstract: A sensing head for detecting flux representative of signals recorded on a magnetic medium includes dual magnetoresistive (MR) elements, an in-gap flux guide partly disposed between the elements and a flux closure piece having ends located adjacent to the ends of the MR elements. The assembly provides increased signal sensitivity and minimizes or eliminates the possibility of electrical or magnetic shorting of the elements which may occur by smearing of the MR sensing elements if the elements are disposed at the air bearing surface of a head slider in contact with a rotating disk.

Abstract: A target for use in automatic positioning systems that allows the automatic positioning system to align an edge in the pattern laid down with the target on a substrate with an edge in the pattern on a mask. The target compensates for variations in the size of the target and the target's associated pattern due to process variations in forming the target from an initial mask having the target and pattern. The target is symmetrical about a first axis and asymmetrical about a second axis where the first and second axes are orthogonal to each other. The target has two edges that will be detected by a sensing device in the automatic positioning system when the target is scanned along one axis and one edge that will be detected by the sensing device when the target is scanned along the other axis. The positioning system will detect the center of the target as being in the middle of the location of the two detected edges in one axis and the location of the detected edge in the other axis.

Abstract: A wear-resistant end cap is provided for an air bearing slider of a thin film magnetic recording head useful in a disk drive. The slider has an air bearing surface that is positioned adjacent to a rotating surface of a magnetic disk during data recording or readout. A thin film transducer is deposited on the trailing end of the slider perpendicular to the air bearing surface. A laminated end cap is deposited on the trailing end surface disposed normal to the disk recording surface to protect the transducer. The end cap includes a first lamination disposed with an edge in a plane parallel to the air bearing surface of the slider and a second contiguous lamination of a different material having an edge in the plane whereby the edge areas of the contiguous laminations have relatively more wear resistance than the wear resistance of an equivalent edge area of either material taken alone.

Abstract: A method of manufacturing a thin film magnetic transducer in which a layer of photoresist material is used to pattern the turns of a bi-level electrical coil. The thickness of the photoresist layer is increased to the maximum height of the bi-level coil. A multi-turn spiral type rectangular trench is formed to define the pattern of the coil structure. In the first coil plating step, a first coil section is plated in the trench to approximately the midpoint of its height. The layer of the resist material is then cured and a blocking mask is deposited over the portion of the first coil section that is not to be further increased in height. The area of the coil that is not blocked by the blocking mask is again plated using the initial pattern until each partial turn in the unblocked section reaches the top of the groove. The cured resist material and the blocking mask are then removed.

Abstract: A tripad air bearing slider useful in a disk drive is designed with two outer pads that extend from two or more tapered sections at the leading edge of the slider towards the trailing edge. The pads are configured and angled so that a desired lift force is obtained that acts in opposition to a force provided by a spring loaded flexure or load beam. The angles that define the shape of the three pads are formed by simple mechanical cutting, using a diamond cutting wheel, for example, or alternatively by ion milling or reactive ion etching.

Abstract: A method of assembling a head stack on a pivot bearing for use in a head positioning mechanism of a disk drive in which a plurality of different head stack components are clamped on the bearing comprises providing a plurality of head stack components, each having an opening for receiving the bearing. The head stack assembly includes two pairs of head arms, spacers and a flat coil member. A caddy positions the components with their respective openings disposed on a common axis. The head arm assemblies are positioned in the caddy with the openings biased against each other and disposed on the common axis. The flat coil member is placed between the pairs of arm assemblies with its opening on the common axis. The head stack components in the caddy are angularly aligned on the common axis. A threaded end of the bearing is inserted through the openings and receives a clamping nut which is tightened to clamp the components on the bearing for conjoint movement with the flat coil component. The caddy is then removed.

Abstract: A thin film magnetic head is fabricated with a multiplicity of magnetic yokes that interact effectively with an electrical coil. The magnetic P1 and P2 pole sections of the yoke are very narrow and form closely spaced envelopes about the coil. The multiple yokes are inductively linked to the coil so as to provide an increased number of flux interactions for a given length of coil turn. With this magnetic head design, signal output is increased, thermal noise is reduced, and the signal-to-noise ratio is effectively improved.

Abstract: A thin film magnetic head incorporates an inductive write portion including two pole/shield layers and a read portion including a giant magnetoresistive (GMR) element. The pole/shield layers are relatively thick and serve as conductive leads which can carry high current with minimal heating and low current density. The GMR element defines data track width and thus minimizes off-track reading of data.

Abstract: A system for testing a voice coil member of a rotary actuator head stack assembly (HSA) of a disk drive includes a plurality of testing circuits, each of which selectively performs at least one predefined test on the voice coil member. During testing, the head stack assembly is removably mounted on a base plate with the axis of rotation of the head stack assembly normal to the top surface of said base plate. A flat reference coil is disposed in a fixed position parallel to the top surface of the base plate to provide an inductively coupled relationship between the reference coil and the coil under test. The ends of the coil under test are connected to a pair of terminals in the base plate. A polarity test circuit for determining the polarity of the coil under test is connected to the terminals. Other test circuits are selectively connected to the terminals and the tests are conducted in a controlled sequence without the need to move the fragile head stack assembly.

Abstract: A magnetoresistive read transducer includes a magnetoresistive (MR) layer having end regions spaced by a central active regions. A pair of hard-magnetic layers provide the longitudinal magnetic bias to the magnetoresistive layer. Each of the hard-magnetic layers is disposed in contact with one of the end regions of the magnetoresistive layer. In addition, a pair of electrical leads provide the bias current to the magnetoresistive layer. Each of the electrical leads is also disposed in contact with one of the end regions of the magnetoresistive layer. This arrangement enable the transducer of the present invention with the most optimal design. In essence, electrical current directly passes through the central active region of the magnetoresistive layer via the electrical leads as a low electrical resistance path. Magnetic flux of the longitudinal bias directly passes through the central active region of the magnetoresistive layer with a reduced probability of magnetic discontinuity.

Abstract: A thin film read-write magnetic head includes first and second adjacent magnetic layers forming a magnetic circuit path with a transducing gap, a flux sensing element disposed in the plane of one of the magnetic layers, at least one magnetic shunt valve member disposed around the flux sensing element, the valve member being disposed in the same plane as the one of the magnetic layers in which the sensing element is disposed. A conductor is electrically connected to the flux sensing member and magnetically coupled to the shunt valve member to apply a magnetic field to the shunt valve member to magnetically control the shunt valve member.

Abstract: A magnetoresistive transducer includes a magnetoresistive layer having end portions spaced by a central active portion. The longitudinal bias for the magnetoresistive layer is cooperatively furnished by a pair of hard magnetic bias regions. Each of the two hard magnetic bias regions includes a plurality of magnetized layers and each bias region is disposed in contact with one of the end portions of the magnetoresistive transducer. The magnetic flux required for the magnetoresistive layer to maintain a single domain state is adequately provided by the hard magnetic bias regions. In one embodiment, a substantially uniform thickness for the entire transducer is achieved, allowing the longitudinal bias to be continuously supplied to the magnetoresistive layer. In another embodiment, thinner hard magnetic bias regions provide improved step coverage for the second read gap thereby increasing yield. Also the thinner hard magnetic bias regions provide a significant increase of planarization of the write poles.

Abstract: A tool for assembling a head stack on a pivot bearing of a magnetic head positioning mechanism in which a caddy and base combination cooperate to position a plurality of different head stack components in an aligned relationship to permit the pivot bearing to be inserted through an opening in each component adapted to receive the bearing. The head stack components to be positioned include two pairs of head arm assemblies, spacers and a flat coil member. The component caddy is readily removable from the caddy base. The caddy and base include vertical projections that define a slot for receiving each of the head arm assemblies with the ends of each pair containing the openings biased against each other and the openings disposed on the common axis.

Abstract: An air bearing magnetic head slider with leading and trailing edges and substantialy parallel sides has a pair of side rail members and a two segment center rail member. The side rail members extend on the slider from the leading edge to a position which is less than the distance between the leading edge and the trailing edge, while the center rail member extends to the trailing edge from the leading edge. This structure permits near or pseudo-contact between a transducer located on the trailing edge and a magnetic recording disk over which the slider flies.

Abstract: The air bearing surface (ABS) of a head slider is formed with configured rails and leading edge tapers. In implementations of the invention, two side rails extend only partially from leading edge tapers to the slider trailing edge. The inner edges of each side rail are formed with at least two opposing angles so that at least two rail sections vary in width along the length of the rail. Each side rail is shaped with an oblique angle to reduce the rail width and a reverse angle to form the sections of differing widths. The leading edge side tapers may be angled for control of pitch stiffness of the slider. In one embodiment of the invention, a third center rail extends from a center taper to the slider trailing edge where the transducer is located. In another embodiment, a short center pad is provided at the trailing edge. In an alternative design, only two side rails are used without a center rail or pad.

Abstract: An automated system for forming a taper on thin film magnetic heads comprises a lapping fixture positioned in apposition to a rotary lapping plate. A ceramic bar, upon which the magnetic heads are deposited and from which air bearing head sliders are fabricated, is attached to an adjustable transfer tool that is secured to a yoke holder. The holder is fixed securely on the lapping fixture so that the air bearing surface of the magnetic heads face the surface of the lapping plate. During the tapering process, data signals are obtained representative of the length of the taper being formed upon the heads spaced along the bar. The signals are calibrated and processed by a computer which provides command signals for varying the weight or pressure upon the lapping fixture across the fixture during tapering, allowing uniformity of taper to be achieved along with automatic termination of the tapering process upon obtaining the desired taper across the ceramic bar.

Abstract: A method and means for reducing readback non-repeatability in thin film heads due to non-repeatablele domain structure, comprising the steps of depositing a layer of antiferromagnetic material, such as MnFe, to create larger uniaxial anisotropy, and localizing such a layer in the upper magnetic pole to improve head performance without sacrificing efficiency. In a particular implementation, alternating layers of NiFe/MnFe/NiFe, each 500 Angstroms thick, are deposited, followed by a sputtered seed layer for subsequent plating. After lapping to correct throat height, the head is then heated above the Neel temperature of MnFe and cooled in the presence of an applied magnetic field.

Abstract: A thin film magnetic head is fabricated with shaping magnetic thin films, preferably formed of Permalloy, which have a stepped configuration. The thin films are deposited between the insulation layer surrounding the electrical coil and below the second pole layer P2 to form a double yoke. The thin films have corners at the stepped areas which pin the domain sites so that the magnetization of the P2 layer is properly aligned, thereby improving the data signal that is being recorded.