Abstract: The embodiments disclose a method of surface tension control to reduce trapped gas bubbles in an imprint including modifying chemistry aspects of interfacial surfaces of an imprint template and a substrate to modify surface tensions, differentiating the interfacial surface tensions to control interfacial flow rates of a pre-cured liquid resist and controlling pre-cured liquid resist interfacial flow rates to reduce trapping gas and prevent trapped gas bubble defects in cured imprinted resist.

Abstract: Methods of machining a single piece hub with integral upper and lower female cones includes providing a single piece hub with upper and lower conical voids having respective narrow ends proximal each other and respective wide ends distal each other. Surfaces of the voids are machined using a tool provided from a single side of the hub that is dimensioned to fit through an opening defined by the interface between the narrow ends of the conical void. The tool can be moved parallel to a rotational axis for accessing conical surfaces of both voids and perpendicular to the rotational axis while contacting the surfaces so as to produce a final machined surface.

Abstract: A method or apparatus that can form and test a data block variant by flipping a selected potentially bad bit that is consecutive with 1 or 2 sequences of several potentially good bits of a received block. The variant correctability test is optionally repeated several times before receiving another data block, in the event of ECC failures, each repetition using a different block variant.

Abstract: To simplify fabrication of an integral hub piece, the opening between the upper and lower female cones in this hub has sufficient width or radial dimension to allow access to both cones from one side of the hub with the cutting tool. A cutting tool is used which has a width smaller than the opening between the cones. Preferably, the tool has a width which is about equal to or smaller than an angular dimension through this opening which is defined by extending surfaces of the upper and lower female cones. If this limitation is satisfied, both cones can be created with a single machine set up operating from one side of the integrated hub. Preferably the tool should only move orthogonal or parallel to the cutting tools rotational center axis.

Abstract: To simplify fabrication of an integral hub piece, the opening between the upper and lower female cones in this hub has sufficient width or radial dimension to allow access to both cones from one side of the hub with the cutting tool. A cutting tool is used which has a width smaller than the opening between the cones. Preferably, the tool has a width which is about equal to or smaller than an angular dimension through this opening which is defined by extending surfaces of the upper and lower female cones. If this limitation is satisfied, both cones can be created with a single machine set up operating from one side of the integrated hub.

Abstract: The present disclosure is directed to systems and methods of rewriting defective tracks in a data storage device. In a particular embodiment, the method includes writing a servo pattern on a data storage surface having tracks, detecting a defective track, and rewriting information on the defective track. The method also includes failing a test when a number of defective tracks is greater than a threshold. The method also includes rewriting servo bursts.

Abstract: A disc drive system includes a recording disc rotatable about an axis, a slider supporting a transducing head for transducing data with the disc, and a dual-stage actuation assembly supporting the slider to position the transducing head adjacent a selected radial track of the disc. The dual-stage actuation assembly includes a support structure supporting the slider in proximity to a surface of the disc, a microactuator and a capacitive position sensor. The support structure is coarsely positionable by a main actuator. The microactuator includes a stator attached to the support structure and a movable rotor operatively attached to the slider, the rotor being connected to the stator by at least one flexible beam. The capacitive position sensor connects the stator to the rotor, and provides a relative position signal representing a state of displacement of the microactuator.

Abstract: A perpendicular magnetic recording medium having a substrate, a seedlayer on the substrate and a magnetic underlayer on the seedlayer, the magnetic underlayer having an easy axis of magnetization substantially directed in a radial or transverse direction, and a process for manufacturing the perpendicular magnetic recording medium are disclosed.

Abstract: Sputter-deposited amorphous NiNb films on glass or glass-ceramic substrates have good adhesion with the substrates, and reduce lithium migration significantly. Longitudinal magnetic recording media deposited on oxidized NiNb sealing layers have very good magnetic recording performances and are suitable for high density recording application.

Abstract: A system for transferring information to and from a magnetic disk is disclosed wherein the information may be encoded on a data track in a large number of polarization orientations in comparison to conventional bidirectional recording schemes. In one embodiment of the present invention, it is contemplated that a single segment may be polarized in eight different orientations, each of which being distinguishable from each other by a read/write head. Polarization of a segment in one of eight different orientations significantly increases the amount of information which can be stored in any given segment relative to conventional systems which are polarized in only one of two orientations. Thus, the amount of information which may be stored on a disk may be increased without having to alter the linear or radial density of the disk.

Abstract: An air bearing slider for a disc drive includes an air bearing surface defined on the disc opposing face at least in part by a first step or cavity. An additional corner step is defined in bar processing, deeper than the first cavity. With the corner step, the first cavity does not extend quite all the way to the corner of the slider. The corner of the slider, formed on one face by dicing of the bar into individual sliders, is at an additional depth due to the corner step. The corner steps are preferably narrow, such as nominally one to two times the tolerance value on the dice cut. If a shock event occurs which causes the air bearing slider to contact the disc at certain roll and pitch angles, the corner step edge will contact the disc rather than the dice cut corner. The corner step thus lessens the probability of contact between the disc and the corners of the air bearing slider, and contact with a dice cut edge of the slider is avoided.

Abstract: A light abrasive texture is applied over the data zone of a thin film magnetic disc, while a surface texture of a second roughness is applied over the landing zone. A lubricant is applied over both the landing zone and the data zone. The lubricant is a high molecular weight PFPE lubricant which has been fractionated by supercritical fluid fractionation in carbon dioxide to exclude the fractions of low molecular weight and to exclude the fractions of very high molecular weight.

Abstract: A transducing head has an air bearing surface and includes a top shield, a bottom shield, a read sensor, and a first flux guide. The top shield has both a substantially rectangular non-recessed portion and a substantially rectangular recessed portion. The non-recessed portion of the top shield extends from the air bearing surface to the recessed portion of the top shield and has a thickness greater than a thickness of the recessed portion of the top shield. The bottom shield has both a substantially rectangular non-recessed portion and a substantially rectangular recessed portion. The non-recessed portion of the bottom shield extends from the air bearing surface to the recessed portion of the bottom shield and has a thickness greater than a thickness of the recessed portion of the bottom shield. A length of the non-recessed portion of the top shield is substantially equal to a length of the non-recessed portion of the bottom shield.

Abstract: A method for controlling flying height at the interface of a magnetic head and a magnetic storage medium is described. The flying height is controlled by applying a voltage between head and medium. This controls the vertical movement of the head, and thus, may increase or decrease the flying height. For example, the flying height may be changed with surface texture to achieve high writing/reading density, where the flatness of the medium is high. Also, the contact between the head and medium may be limited where the texture includes projections such as laser bumps.

Abstract: A writer pole and a method for fabricating a writer pole is disclosed. The method comprises fabricating a conductive seed layer on a gap substrate and then fabricating a nonmagnetic feature on the seed layer where the nonmagnetic feature has a top layer and a plurality of sides. The seed layer and nonmagnetic feature are covered with photoresist. A window is fabricated in the photoresist, exposing a portion of the nonmagnetic feature and a portion of the seed layer, thereby exposing a top portion and a side portion of the nonmagnetic feature and exposing a portion of the seed layer. The portion of the seed layer in the window area is removed from the gap substrate. A pole is fabricated on the top and side portions of the nonmagnetic feature in the window area.

Abstract: A storage medium is provided that includes a texture zone having a plurality of protrusions. Each of the protrusions is separated by a short circumferential pitch. Alternatively, the texture zone includes a plurality of protrusions with a circumferential pitch less than the diameter of any protrusion. The resonance excitation between the magnetic head and the storage medium in the data storage system is reduced by forming the texture zone with the protrusions that cause the excitation frequencies of the data storage system to shift away from its resonance frequencies.

Abstract: A micro disc drive assembly includes a wafer-level actuator arm, a wafer-level suspension connected to the actuator arm, and a head-carrying slider supported by the suspension over a rotatable disc. A microactuator motor is located between the actuator arm and the suspension, and is operable to move the suspension with respect to the actuator arm to position the head-carrying slider adjacent to a selected track of the rotatable disc. By forming the actuator arm and suspension at the wafer level, significant size reductions can be made, and the stiffness of the arm and resonant frequency of the disc drive are increased. A main actuator may also be provided in one embodiment, formed at the wafer level and including coils deposited on a wafer substrate, to coarsely position the actuator arm, suspension and head-carrying slider adjacent to the selected track of the rotatable disc.

Abstract: A leader pin assembly for attachment to tape as a generic and space-efficient interface between tape and equipment which manipulates the tape, and a method for making the same. The leader pin assembly preferably includes a leader pin, an elastomer element, and a clip. The leader pin is barbell-shaped, having enlarged ends and at least one pair of flanges each spaced a distance from a respective enlarged end to define a pair of recesses and a center section of the leader pin. The center section of the leader pin is sized to permit tape to be wound around the center section, with the elastomer element surrounding the tape and with the clip snugly surrounding the elastomer element to keep the tape securely in place around the center section of the leader pin. The end surfaces of the leader pin may have an outward curve to ensure smooth movement across equipment surfaces during leader pin assembly manipulation. Also the edges of the leader pin may be radiused.

Abstract: A thin-film magnetic recording disc for use with a read/write head in a disc drive includes a substrate, a magnetic recording film disposed over the substrate, and a protective overcoat on the recording film. The recording disc has an outer layer that includes a solid fluorocarbon and a perfluoropolyether (PFPE) oil. The disc can be used as a data storage media for a digital computer and, in particular, with a read/write head in a disc drive. The addition of the fluorocarbon layer can improve the tribology of the disc, thereby reducing wear and improving the long-term performance of the magnetic disc.

Abstract: A system includes shared Small Computer System Interface (SCSI) storage devices for processing clients coupled by a fiber channel interface. The storage devices include storage blocks, and locks controlling their use by clients. Clients issue actions to the storage devices for performing operations on the locks. A client may exclude other clients from using storage blocks using a state element to acquire the lock for shared or exclusive use. If the client modified the data, a version counter in the lock is updated when the lock is released. If an activity bit is set, the version counter is updated upon both reading and writing. Other clients can forcibly release a lock owned by a failed client by monitoring its version counter. Expiration timers associated with the locks allow acquired locks to be released by timing out. A serverless global file system (GFS) manages use of the shared storage resources, and allows remapping of the locks to the storage blocks, for example, based on activity of the locks.