Abstract: A magnetic recording medium is provided with a dual layer protective overcoat system comprising an AlN corrosion barrier layer and a protective carbon layer thereon. The AlN layer effectively prevents or significantly reduces Co diffuision to the medium surface. Embodiments include magnetic recording media comprising an AlN corrosion barrier layer over a magnetic layer and a layer of amorphous hydrogenated carbon, amorphous nitrogenated carbon, amorphous hydrogen-nitrogenated carbon, ion-beam deposited carbon or cathodic-arc-deposited carbon on the AlN corrosion barrier layer.

Abstract: A recording head for use with magnetic recording media includes a current perpendicular to plane (CPP) type giant magnetoresistive (GMR) read element, with the alternating magnetic and nonmagnetic layers within the GMR read element either perpendicular or angled to the read head's shields. This structure maximizes the number of alternating layers within the GMR read element, and minimizes the area available for flow of the test current. Both total resistance of the GMR element, and the change in resistance as a function of changes in magnetic flux, relative to total resistance, are thereby increased. The sensitivity of the GMR read element is thereby increased, permitting storage of information within magnetic recording media at greater densities. The invention also includes a method of manufacturing a read head using such a GMR element.

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 spindle motor assembly (18) includes a polymeric motor shaft (20), a polymeric hub (22) to support a rotating disc (24), and a stator (40) disposed in an internal cavity defined by the hub. A resilient snap-in retainer (62) is molded to the motor shaft (20) to hold the hub (22) in place. A surface of the polymeric hub and an opposing surface of the polymeric motor shaft form a hydrodynamic bearing.

Abstract: A method for compensating digital samples of an asymmetric read signal is presented. The method involves reading a digital sample of an asymmetric read signal V(t) (160), generating a compensated sample at least when the digital sample requires compensation (164), and outputting either the digital sample (168) or the compensated sample (166). Also presented is an asymmetry correction block (158) of a read channel (144) of a disc drive (110) that includes an input (200), a level detector (202), a compensator (204), and an output (208). The level detector (202) and the compensator (204) receive the digital sample through the input (200). The level detector (202) determines whether the digital sample requires compensation. The compensator (204) generates a compensated sample at least when the digital sample requires compensation. The output (208) selectively outputs either the digital sample or the compensated sample.

Abstract: A low height disk drive having an overall height of approximately one inch (1″). The drive includes a head disk assembly, including a base plate, two disks rotatably supported on the base plate, a motor for rotating the disks, at least two heads for reading information from and writing information on respective ones of the disks; an actuator, supported on the base plate and responsive to control signals, for selectively positioning the heads with respect to the disks, and a cover sealably attached to the base plate to enclose the storage device, the head, and the actuator. The disk drive also includes control circuitry for generating control signals, and for providing information signals to and receiving information signals from the heads. The head disk assembly and the control circuitry have a combined height of approximately one inch or less.

Abstract: A write head for writing information bits to magnetic storage media comprises a first write pole for producing a first magnetic field in a first direction and a second write pole for producing a second magnetic field such that the combined field from the two poles lies either substantially along the first direction or in a second direction that is substantially orthogonal to the first direction. The second write pole includes a free layer having magnetization controlled by spin transfer torque, and a first spacer positioned between the free layer and the first write pole. The write head can further include a pinned layer and a second spacer positioned between the pinned layer and the free layer. A disc drive that includes the write head and a method of writing to magnetic storage media that utilizes the write head are also included.

Abstract: A method of detecting a leak of low-density gas from an enclosure containing a rotating storage disc includes monitoring a signal which varies in response to variations in the concentration of the low-density gas in the enclosure. Additional quantities of the low-density gas are added to the enclosure when the monitored signal indicates that the concentration has dropped below a predetermined level. Monitoring the concentration of the low-density gas may include monitoring actual concentration levels of the gas using a pressure sensor located within the enclosure or monitoring disc mode vibration amplitudes using an accelerometer attached to the enclosure. Indirect monitoring of the vibration amplitudes may also be accomplished using sensors such as a laser Doppler vibrometer, a capacitance probe or the servo head position feedback circuitry found within a disc drive or a dedicated servo track writer.

Abstract: A process for evaluating a current technological strategy for an organization is disclosed. The process examines the current technological strategy for potential threats and opportunities based on a landmark technology identified during a technology scan. The potential threats and opportunities are evaluated to develop a proposed strategy indicative of the current technological strategy integrated with the landmark technology. A pilot study is performed on the proposed strategy to render a recommendation on whether the proposed strategy should be adopted or rejected by the organization. Based on the recommendation, the proposed strategy may be either implemented or saved for future reference and re-evaluation.

Abstract: A method of recovering data from a data sector through adaptive fly height to improve reliability of a disc drive is disclosed. Encountering a data error in a data sector initializes an error recovery routine that increases a fly height of the read/write head for asperity encounters, or decreases the fly height of the read/write head for low amplitude read signal encounters. In the case of asperity encounters, when the increased fly height fails data recovery, the read/write head is positioned off track, then lowered to burnish the asperity and the data sector is re-read.

Abstract: A disc storage system having a host computer interface adapted to coupled to a host computer, a disc storage medium having a disc surface and a spindle motor coupled to the disc adapted to rotate the disc. The disc includes spare data regions and permanent data regions. A transducer is positioned for reading and writing data on the disc surface. The system further includes a controller adapted to write data on the spare data regions to thereby provide a non-volatile write cache.

Abstract: A microactuation system selectively alters a position of a transducing head carried by a slider in a disc drive system with respect to a track of a rotatable disk having a plurality of concentric tracks. The disc drive system includes a load beam and a base for attachment to an actuator arm and a suspension for supporting the slider over the rotatable disc. The microactuation system includes a piezoelectric element attached between the actuator arm and the load beam and a beam connecting a stationary portion of the load beam to a moving portion of the load beam. The piezoelectric element is deformable in response to a voltage applied thereto. The beams are sufficiently compliant to permit movement of the moving portion of the load beam with respect to the stationary portion of the load beam upon deformation of the piezoelectric element.

Abstract: Disclosed is a method of compensating for non-optimal operating conditions during a sine seek operation. A disc drive with a seek controller provides a feedforward signal to an actuator during a portion of the operation of an actuator and provides a velocity signal during another portion of operation of the actuator. The controller also stores a velocity error switch point. If it is determined that the feed forward signal is lower or higher than a first nominal value, then the feed forward signal provided by the controller is adjusted. Furthermore, if it was determined that the feed forward signal is lower than the first nominal value, the velocity error switch point is decreased.

Abstract: A method for forming a perpendicular magnetic read/write head having an air bearing surface and comprising a substantially planar top pole and a shared pole is disclosed. The steps include forming a top pole, a shared pole, and a yoke wherein the top pole and shared pole are connected distally from the air bearing surface by a yoke. A conductive coil is formed that wraps around the top pole and is positioned adjacent to the air bearing surface, with a lower portion of the coils extending between the top pole and the shared pole.

Abstract: An automatic tape cartridge loader includes a moveable shuttle, for receiving the tape cartridge, and elements for automatically actuating the shuttle during loading and unloading operations. The shuttle includes a door-opening feature, preferably formed as an integral element of one wall of the shuttle. The door-opening feature engages a sliding tape access door on one side of a tape cartridge, as the cartridge is inserted into the shuttle. The preferred embodiment of the shuttle also includes one or more extruded features formed on an opposite wall of the shuttle to justify the cartridge within the shuttle and thereby ensure engagement of the door-opening feature with the access door during cartridge insertion. These features are passive elements, in that they require no mechanical or electrical actuation or any parts that are moveable relative to the shuttle. Instead, these elements rely entirely on the movement of the cartridge into the shuttle to open the access door.

Abstract: A disc head slider includes a leading slider edge, a cavity dam, a subambient pressure cavity, which trails the cavity dam and has a cavity floor, and first and second rails disposed about the subambient pressure cavity. Each rail has leading and trailing bearing surfaces and a recessed surface extending between the leading and trailing bearing surfaces, which is recessed from the bearing surfaces and raised from the cavity floor, across the rail width. Recessed leading channels are positioned near the leading slider edge and have a leading channel end open to fluid flow from the leading slider edge, non-divergent channel side walls, and a trailing channel end closed to the fluid flow. A trailing channel is recessed within each of the trailing bearing surfaces and has a leading channel end open to fluid flow from the respective recessed surface, non-divergent channel side walls, and a trailing channel end closed to the fluid flow.

Abstract: An electrical connector is disclosed. The electrical connector includes a housing made of a near insulative material. The near insulative material has a resistance to current flow in the presence of low voltage current and has a surface resistivity which allows sufficient current flow to dissipate static electrical charges. The housing has a surface resistivity level within the range of 104 to 1010 ohms per square, and preferably within the range of 105 to 108 ohms per square. The material used for the housing has negligible current flow in the presence of low voltage current such as when the conductor is conducting signals or electricity during normal operations. The current flow is in an amount sufficient to dissipate a static charge on the housing to a level where placing the jumper onto a set of pins will not produce a failure in a microchip electrically coupled to the jumper.

Abstract: This invention presents a method and system for testing a disc drive head usable with a disc drive head testing device. The steps for this include determining an unknown electrical property of the head testing device. This is done by generating output signals at the output stage. The testing device property is then computed by solving for the unknown electrical property based on the output signals generated for each of the known test devices. For each disc drive head under test, the head is coupled to the input lead and exposed to a stored magnetic data pattern to generate a read signal at the input lead. The measured difference affects the generated read output signal. The read output signal is adjusted based on the testing device property and the measured property to compensate for differences in the measured property.

Abstract: A bias current for a magnetoresistive read head is selected by defining a tuning range based on a maximum and a minimum bias current value for the head. A plurality of read operations are iteratively performed using a different bias current value over the tuning range for each iteration. The results of each read iteration are measured and a bias current is selected on the basis of the read error rates, and particularly those bias currents associated with the lowest read error rate.

Abstract: A voice coil for a head positional assembly of a disc drive. The voice coil including a dampener which dampens vibrations occurring in the voice coil. The dampener includes a constraint material and a viscoelastic material.