Abstract: A recording disk contains at least two types of servo sector format, including a first type having a relatively larger track identifying field containing the track number, and a second type having an abbreviated track identifying field identifying a track within a range of tracks, the range being less than the full range of tracks on the disk surface. Preferably, Gray code encodings are used, the first type of track field contains sufficient Gray code bits to identify the ful track number, every Nth servo sector is of the first type, and all servo sectors in between are of the second type, N being at least 2. As a result, the disk area required for track identification is reduced, and the additional disk space available can be used to expand the PES field.

Abstract: A calibration method for determining the flying height of a glide slider for disk glide height testing is disclosed. The method utilizes a disk with bumps in situ on a disk glide height tester. The method automatically takes into account disk topography, mounting tolerances, and slider roll.

Abstract: A method and apparatus for estimating the flyheight of an airbearing slider in a storage device using variable spindle velocity. The slider floats on an airbearing over a rotating storage disk. The storage disk includes a washboard-sequence having washboard-sections each comprising surface profile variations having a different pitch. The pitches are selected from within a range of values likely to excite an airbearing resonance of the slider as the storage disk rotates at a plurality of discrete velocities. For each of the washboard-sections and at each of the velocities, a maximum amplitude of flyheight modulation of the slider resulting from the slider floating over that washboard-section is measured as the storage disk rotates at that velocity. A determination is made of the velocity/washboard-section combination that caused the largest measured flyheight modulation.

Abstract: A head suspension for maintaining a gap between a read-write head and a data storage disk comprises a heater for heating gas in the gap; and a sensor for generating an output indicative of the thickness of the gap. The sensor generates the output in dependence on thermal conductance across the gap. The apparatus can be used to control the thickness of the gap.

Abstract: A method of initializing a magnetic sensor having two antiferromagnetic layers is described. The method takes advantage of the spin flop effect such that the two antiferromagnetic layers may be orthogonally initialized. The signal polarity of the sensor is well controlled.

Abstract: A method is disclosed for precision control of pole tip recession of magnetic recording heads. This is achieved by first constructing the head so that the thermal expansion coefficient of the recording head is different from the thermal expansion coefficient of the overcoat. Then the recording head is heated during the lapping process of the slider and recording head. The average and distribution of the recession between the overcoat and the recording head pole tips are improved.

Abstract: The present invention relates to computer storage systems which have a tip (24) directed close or in contact to the storage medium (10) by which bit-writing and bit-reading is enforced. It is proposed to use a magnetizable storage medium (10), expose it to an artificial, external magnetic field H coupled externally to the storage medium, and—during bit writing—to concurrently apply heat very locally in bit size dimension in order to let the external magnetic field become locally larger than the (temperature-dependent) coercive field at the location (32) where heat is applied.

Abstract: A magnetic recording disk is provided having an amorphous preseed layer of chromium, titanium, and yttrium. The use of the preseed layer improves the magnetic performance of the disk including signal to noise, inplane orientation, and readback pulsewidth.

Abstract: This invention provides a disk which has an in-plane oriented magnetic recording layer on a glass, ceramic, or other nonmetallic substrate and a method for making the disk. A thin layer of material is deposited on the substrate to form a texture stop layer. A texturable layer is then deposited on the texture stop layer. This texturable layer is textured before the magnetic layer is deposited. The disk combines all the advantages of a glass or ceramic substrate along with the advantages of an oriented magnetic medium.

Abstract: An etch barrier to be used in a photolithograph process is disclosed. A silicon rich etch barrier is deposited on a substrate using a low energy deposition technique. A diamond like carbon layer is deposited on the silicon rich etch barrier. Photoresist is then placed on this etch barrier DLC combination. To form photolithographic features, successive steps of oxygen and flourine reactive ion etching is used.

Abstract: A method is disclosed for determining the presence of response abnormalities in magnetic sensors. The method includes placing the sensor in an applied magnetic field and collecting sensor resistance information as the magnitude and direction of the applied field is altered. The resistance values are then examined to determine the presence of response abnormalities.

Abstract: The present invention provides a depopulation version hard disk drive apparatus that has a reduced number of magnetic heads and suspension arms from a standard hard disk drive apparatus, wherein the magnetic head can still be properly controlled during a loading state. The hard disk drive apparatus includes a ramp which interfaces with the suspension arm when loading and unloading the arm. An angle of a second slope surface 61c of the ramp in the depopulation version hard disk drive is set larger than that of the corresponding slope surface of the ramp 6 the a standard version hard disk drive.

Abstract: A magnetic head handling glove capable of preventing the buildup of static charges and electric charge leakage and capable of withstanding use in clean rooms is described. In the magnetic head handling glove 1 of the present invention, the outer surface alone or both the outer surface and inner surface of a conductive glove 2 are coated with dissipative material 3,4. This results in coating of the conductive glove with materials useable in clean rooms and may suppress possible contamination that can result when a conventional conductive glove, lacking in such coating of dissipative material, is used directly in a clean room. Besides this, the conductive glove 2 is configured to be grounded directly with wire 5. In this way, even an operator prone to the buildup of static charges can be sufficiently prevented from building up static electrical charges and electric charge leakage.

Abstract: A data storage system capable of removing disk surface irregularities and/or contaminant particles on disk surfaces that may cause thermal asperities in the transducer output is provided. The data storage system provides selective in-situ operation between a normal read/write operation and a disk surface burnishing operation. One embodiment provides a data storage system, including: a data storage disk connected to a rotating actuator; a suspension load beam movably disposed above the data storage disk; and an air bearing slider assembly pivotally attached to the suspension load beam, the air bearing slider assembly including: a slider having an air bearing surface; a transducer disposed in a distal portion of the slider; a burnishing element disposed on the air bearing surface; and a pitch angle control assembly disposed in connection with the slider to control a pitch angle of the air bearing surface.

Abstract: A multiple actuator disk drive is disclosed. The mechanical vibration in one actuator induced by motion in the second actuator is greatly reduced by providing an independent bearing shaft for each actuator. The bearing shafts are mounted substantially along the same geometric axis.

Abstract: A disk drive device comprising a disk-shaped recording medium, having a recording surface on which a plurality of tracks having a predetermined width in a radial direction are defined, said recording surface including a first area wherein a plurality of recording tracks and a plurality of non-recording tracks are located so as to form an alternating pattern along the radial direction of the recording surface.

Abstract: A system which reduces power dissipation in a data storage device having a normal operating mode and at least one power saving mode by computing a predicted amount of power that would be saved by the device if the device makes a transition from the normal operating mode to the power saving mode; computing a time at which the device should transition from the normal operating mode to the power saving mode, based on at least one predicted amount of power to be saved; and transitioning the device from the normal operating mode to the power saving mode.

Abstract: A method and an apparatus for predicting the recovery time required until the hard disk drive is restored to a usable state from a stand-by state. The recovery time is a time required until the hard disk drive is restored to a usable state from the stand-by state. Then, the predicted recovery time is reported to the host system. When the host system knows how much time is needed until the disk drive is recovered, it can schedule a task to be completed before the hard disk drive is restarted, thereby scheduling of all the tasks in the host system can be optimized.

Abstract: A method for assembling a slider suspension assembly for use in a disk drive is disclosed. A ceramic slider with an attached recording head is placed on a suspension and is held in alignment by soldering the electrical connections while the epoxy placed between the slider and the suspension hardens. The method results in a much more economical process which does not require the number of expensive tools needed to carry out the conventional process.

Abstract: A method of corrosion susceptibility testing of a magnetic recording head is disclosed. The method includes applying simulated disk corrosion products containing cobalt salts to the recording head. The recording head is then placed in an environmental chamber with elevated temperature and humidity. The resistance of the sensor on the recording head is measured after removal from the chamber and compared with the resistance before placement in the chamber. A significant change in resistance indicates a corrosion failure. This component level testing gives a more accurate indication of the corrosion performance of the recording head when placed in a disk drive.