Abstract: A master is provided for use in a magnetic printing process. Illustratively, the master is used for printing servo patterns on a magnetic recording medium. The master includes a substrate on which a magnetic underlayer material is disposed. A second magnetic material is disposed over the magnetic underlayer material so as to form a plurality of teeth adapted for use in the magnetic printing process. The teeth may be formed in the second material by an additive or subtractive process. Further, the dimensions of the teeth may be selected to optimize use of the master in a magnetic printing process on perpendicular media.

Abstract: A method for fabricating a patterned recording medium includes providing a workpiece with a non-magnetic substrate and at least one overlying magnetic layer, laminating a thermal insulation barrier partially in a soft under layer of one of the at least one magnetic layers and forming a topographical pattern including a plurality of trenches in the soft under layer. Blocks of track triplets are formed between adjacent trenches that are magnetically and thermally insulated from other adjacent blocks of track triplets.

Abstract: A disk drive system having a shielded pole write head and media that includes a disk having a soft underlayer (SUL) that is relatively thin in order to save on cost for producing the SUL. The SUL is thin enough that it will become magnetically saturated in the vicinity of the write pole. The thickness of the SUL that will achieve this saturation may be stated as being less than a geometric factor times the ratio of the write pole saturation magnetization divided by the saturation magnetization of the SUL. The geometric factor is the ratio of the write pole area at the ABS to the write pole perimeter at the ABS.

Abstract: A read/write head for a disk drive having a magnetoresistive (MR) read element and an inductive write element suitable for perpendicular recording of data onto a disk having a media layer in which the data is stored perpendicularly to the planar surface of the disk and a soft underlayer (SUL) underneath the media layer to provide a low reluctance return path for the magnetic recording field. The write element is formed on top of a substrate, with the read element on top of the write element on the other side of the write element from the substrate. A pancake write coil coils around a magnetic via that either connects to a write shield adjacent to the read element in one embodiment or directly to one of the read shields in a second embodiment.

Abstract: A slider includes a Tunneling Magneto-Resistive (TuMR) read sensor and a shunt resistor connected in parallel. The shunt resistor may be located in a read structure of the slider. The shunt resistor may reduce a total resistance of the read structure and any corresponding impedance mismatch between the read structure, a transmission line, and a preamplifier. The shunt resistor may be made of a material having a near zero thermal coefficient of resistivity (TCR) to test a quality of the TuMR read sensor. The TuMR read sensor may be deemed defective if its TCR deviates from a population average by a specific criterion. The TuMR read sensor may include a MgO tunneling barrier to improve signal strength. The TuMR read sensor may include a free layer that is able to be saturated with a perpendicular background field to calculate a more accurate TCR of the TuMR read sensor.

Abstract: A write head includes a write return yoke, a write yoke connected to the write return yoke, conductive coils surrounding the write yoke, a write pole tip, and a non-magnetic spacer connecting the write pole tip to the write yoke. The non-magnetic spacer allows for reducing a magnetization of the write pole tip due to a remnant magnetic field in the write yoke. In another embodiment, the write head comprises a write shield, a write return yoke, a write yoke, conductive coils, a write pole tip, and a saturable yoke shunt connecting the write pole tip and the write shield. The saturable yoke shunt directs a limited amount of magnetic flux from the write pole tip to the write shield, such that when there is a remnant magnetic field in the write pole tip, the magnetic flux is directed to the write shield rather than to a disk.

Abstract: A method for fabricating a patterned recording medium includes providing a workpiece with a non-magnetic substrate and at least one overlying magnetic layer, laminating a thermal insulation barrier partially in a soft under layer of one of the at least one magnetic layers and forming a topographical pattern including a plurality of trenches in the soft under layer. Blocks of track triplets are formed between adjacent trenches that are magnetically and thermally insulated from other adjacent blocks of track triplets.

Abstract: A head includes a substrate, an undercoat material, a read structure, and a write structure. The undercoat material at least partially provides electrical insulation between the read structure and the substrate. The read structure allows for reading magnetic fields from a recording medium. The write structure allows for providing particular magnetic fields to the recording medium to write data to the recording medium. The read structure is located at least partially between a portion of the undercoat material and a portion of the write structure. The head further includes at least one of (i) a heating element located at least partially in the undercoat material for providing heat and (ii) a pedestal for at least partially providing thermal conduction between the read structure and the substrate. Also, a thickness of the undercoat material may be set for improving flying height adjustment efficiency.

Abstract: A master is provided for use in a magnetic printing process. Illustratively, the master is used for printing servo patterns on a magnetic recording medium. The master includes a substrate on which a magnetic underlayer material is disposed. A second magnetic material is disposed over the magnetic underlayer material so as to form a plurality of teeth adapted for use in the magnetic printing process. The teeth may be formed in the second material by an additive or subtractive process. Further, the dimensions of the teeth may be selected to optimize use of the master in a magnetic printing process on perpendicular media.

Abstract: A system and method is provided for adjusting a depth of focus in a refractive material without introducing spherical aberration as a result of the focal adjustment. The system and method provide a novel optical path in which a ramped prism is situated between an objective lens and a refractive material. The bottom surface of the prism is positioned parallel to and in close proximity with the top surface of the recording medium. The objective lens and, as appropriate, one or more associated mirrors are positioned so that light exiting the lens is directed along an optic axis that is oriented substantially perpendicular with respect to the ramped top surface of the prism. In operation, light passes through the objective lens and is focused at a fixed optical depth in the refractive block consisting of the prism and recording medium. The objective lens and other optics in the optical path may be moved up or down the prism ramp to adjust the physical depth of focus in the recording medium.

Abstract: A slider for use in a disk drive system with a read/write head that has a write coil as part of a write transducer. The write coil has a center tap thereon for connection to a conductor in addition to the connection of the ends of the write coil to two other conductors. This allows the write coil to be driven from opposite ends with opposite but equal currents in addition to the write currents that are used in write mode or alone in modes other than in write mode, such as just before write mode is entered. The current flowing in or out of the center tap then will be the sum of the currents flowing out or into the opposite ends of the write coil. In this manner, no magnetic fringing field is created since the currents/fields cancel each other out. Also, the power dissipation in the write coil during this time will be approximately the same as in write mode and a similar amount of pole tip protrusion should be produced thereby.

Abstract: A write head for a media drive suited for perpendicularly recording data in adjacent magnetic recording media, the media having a magnetic recording layer and a soft underlayer (SUL). The write head has a pole tip, a write yoke connected to the pole tip, a write return yoke, a write shield, one or more conductive coils surrounding the write yoke, and one or more side shields disposed in close proximity to the pole tip. The write return yoke connects to the write yoke on one end and the write shield on a different end. The one or more side shields are separated from the pole tip and write shields by a non-magnetic material and therefore are “floating” and not directly coupled to the write shield or pole tip.

Abstract: A disk drive includes a drive housing and a storage disk rotatably coupled to the drive housing. In one embodiment, the storage disk includes a first substrate, a spaced-apart second substrate, a damping layer and a rigid substrate spacer. The first substrate is formed from a first material having a first composition and the second substrate is formed from a second material having a second composition. The damping layer is positioned at least partially between the first substrate and the second substrate. The rigid substrate spacer is positioned at least partially between the first substrate and the second substrate, and is formed from a third material having a third composition that is different from the first composition and the second composition. In one embodiment, the first composition is different than the second composition. The first substrate has a first thickness and the second substrate has a second thickness that can be different than the second thickness.

Abstract: A technique for de-gaussing the pole tips and yoke of a write transducer in a perpendicular magnetic recording system is provided. An oscillator in the read channel is configured to produce an adjustable signal pattern output to the preamplifier when a write operation ends for a given time and at a predetermined frequency, such that as the preamplifier write current decays, it decays with transitions (polarity reversals). This results in a decaying AC field being applied to the write transducer at the end of a media write operation, effectively de-gaussing it and reducing the effects of remanent magnetization remaining in the poles and yoke of the magnetic recording head after a write current is turned off. This defeats a potential pole tip lockup or yoke lockup circumstance in the magnetic recording media which can result in an inability to write further data or a possible erasure of valid data on the hard disk with which the write head is associated.

Abstract: Techniques for reducing adjacent track erasure include: a bucking coil having a lower number of turns than the write coil for bucking out a portion of the field induced by the write coil; a hybrid solenoid coil that includes turns that are in a pancake arrangement and turns that are in a solenoid arrangement; a P2 write pole tip with an increasing amount of flare as the distance from the ABS increases; a notch along an edge of the ABS surface of the P1 write pole adjacent to a tooth that extends closest to the P2 write pole; a back notch adjacent to the tooth on the P1 write pole that has a width generally corresponding to the width of the tooth; and a layered structure on the pole tip of the P1 write pole adjacent to the tooth, the layers having at least one of decreasing amounts of saturation magnetization, decreasing amounts of permeability, or alternating layers of magnetic and nonmagnetic material, where the width of the magnetic and nonmagnetic layers is controlled or the characteristics of the magnetic

Abstract: A method for manufacturing a first disk drive includes incorporating a first storage disk having a first storage surface, and a first slider having a first read/write head and a slider mover into the first disk drive. Further, the first read/write head is movably positioned a first head-to-disk spacing relative to the first storage surface. The method also includes determining an incremental power level necessary to be delivered to a second slider mover of a second slider having a second read/write head to adjust a second head-to-disk spacing relative to a second storage surface by a predetermined increment. In addition, the method includes adjusting a first head-to-disk spacing by directing an operational power level to the first slider mover. The operational power level is derived from the incremental power level.

Abstract: A fly height controller measures electrical resistance of a heater element attached to a read/write head as an indication of head temperature and associated flying height relative to a data storage disk, and responds to the measured resistance of the heater element by varying a fly height adjustment signal applied to the heater element to change the temperature of the head and its resulting flying height.

Abstract: A write pole for a read/write head of a disk drive system has a tapered surface on a leading edge thereof. Preferably, the tapered surface has a taper angle of between 0 and 20 degrees from a plane normal to the ABS. By having a write pole with a taper in this manner, sufficient write fields can be achieved even with thinner write pole tips on the ABS surface. By decreasing the thickness of the write pole tip in this manner while maintaining sufficiently high write fields, the skew profile of a write head can be decreased and areal density increased.

Abstract: A disk drive includes a drive housing, a storage disk and a slider. The slider includes a head that magnetically interacts with the storage disk. Further, the slider includes a slider mover that moves a portion of the slider to adjust a head-to-disk spacing during operation of the disk drive. In one embodiment, the slider mover is formed from a material having a thermal coefficient of resistivity that is less than approximately 0.001/° C., such as a copper-manganese alloy, a copper-tin alloy or a gold alloy. The slider mover can be formed from a material having a negative thermal coefficient of resistivity. Further, the slider mover can be formed from a material having a resistivity that is less than approximately 15 microohm-centimeters. Additionally, the slider mover can be formed from a material having a melting point that is greater than approximately 750° C. The disk drive can include a drive circuitry and a lead that conducts electricity between the slider mover and the drive circuitry.

Abstract: A disk drive for storing data includes a drive housing, a storage disk that is rotatably coupled to the drive housing, a slider assembly positioned near the storage disk, and a drive circuitry. The slider assembly includes a head that interacts with the storage disk during a data transfer operation and a slider mover. The drive circuitry directs a first power level to slider mover to maintain the head at a first HtD spacing, and a second power level to the slider mover to maintain the head at a second HtD spacing, and a variable, transition power to the slider mover during a transition between the first power level being directed to the slider mover and the second power level being directed to the slider mover. The transition power is tailored to rapidly move the head between the HtD spacings.