Abstract: The present invention provides a magnetic recording medium and a magnetic disk drive using the same, capable of keeping flying height and posture of the head slider constant when a discrete track medium (magnetic recording medium) includes tracks as data zones, and non-data zones (groove) formed between adjacent tracks.

Abstract: A magnetic storage medium comprises a plurality of discrete magnetic elements and first and second adjoining servo sectors. Each of the servo sectors comprises first and second rows of the discrete magnetic elements extending in a track direction. The second row of the discrete magnetic elements are stacked relative to the discrete magnetic elements of the first row in a cross-track direction that is perpendicular to the track direction. The discrete magnetic elements of the first servo sector are staggered in the cross-track direction relative to the discrete magnetic elements of the second servo sector.

Abstract: A bit patterned magnetic media design for reducing the amount of magnetic material located in the trenches between topographic features is disclosed. An intermediate non-magnetic layer is deposited on the topography prior to depositing the functional magnetic layer on the topographic substrate features. The non-magnetic layer increases the width of the land regions that will ultimately support the functional magnetic layer. The non-magnetic layer also reduces the amount of trench deposition that can occur in the subsequent deposition of the magnetic recording layer. By eliminating most of the magnetic trench material, the amount of magnetic flux and readback interference produced by the trench material is reduced to an acceptable level.

Abstract: A substrate for a recording medium suited for thermally assisted recording methods has a disc shape with a center hole and includes a silicon single-crystal supporting member; an SiO2 film formed on the silicon single-crystal supporting member; a main face having a film thickness of the SiO2 film thereon which is less than 10 nm; a substrate inner periphery end face adjacent to the center hole; a substrate inner periphery chamfer portion adjacent to the main face and to the substrate inner periphery end face; a substrate outer periphery end face positioned on the side of the main face opposite the substrate inner periphery end face; and a substrate outer periphery chamfer portion adjacent to the main face and to the substrate outer periphery end face. A magnetic recording medium includes at least the above substrate and a magnetic recording layer formed on the substrate.

Abstract: There is provided a glass substrate for a magnetic disk in which a maximum height of bumps forming a roughness pattern at a period of smaller than 2 ?m is 6 nm or lower in an annular area having a width of 30 ?m on a main surface on which a magnetic recording area is formed, a number of bumps having a height of 3 nm or higher in a unit area having a circular arc length of 30 ?m within the annular area is one or less, and a difference in arithmetic average roughness between unit areas within the annular area is 0.2 nm or smaller.

Abstract: A magnetic recording medium having a substrate, a first magnetic layer and a second magnetic layer, in this order, wherein an exchange coupling in the first magnetic layer is lower than an exchange coupling in the second magnetic layer, and the first and second magnetic layers are in a film stack so that magnetic grains in the first magnetic layer are exchange coupled by a pathway through the second magnetic layer is disclosed. A method of manufacturing a magnetic recording medium by obtaining a substrate, depositing a first magnetic layer at a first sputter gas pressure and depositing a second magnetic layer at a second sputter gas pressure, in this order, wherein the first sputter gas pressure is higher than the second sputter gas pressure, and an exchange coupling in the first magnetic layer is lower than an exchange coupling in the second magnetic layer is also disclosed.

Abstract: To provide a glass for an information recording media substrate, which is excellent in weather resistance. A glass for an information recording media substrate, which comprises, as represented by mol % based on oxide, from 61 to 66% of SiO2, from 11.5 to 17% of Al2O3, from 8 to 16% of Li2O, from 2 to 8% of Na2O, from 2.5 to 8% of K2O, from 0 to 6% of MgO, from 0 to 4% of TiO2 and from 0 to 3% of ZrO2, provided that Al2O3+MgO+TiO2 is at least 12%, and Li2O+Na2O+K2O is from 16 to 23%, wherein in a case of where B2O3 is contained, its content is less than 1%. The above glass for an information recording media substrate, wherein when the glass is left under steam atmosphere at 120° C. at 0.2 MPa for 20 hours, and the amount of Li, the amount of Na and the amount of K, which precipitate on a surface of the glass are represented as CLi, CNa and CK respectively, CNa is at most 0.7 nmol/cm2, and CLi+CNa+CK is at most 3.5 nmol/cm2.

Abstract: Provided are a magnetic recording medium substrate whereupon a magnetic layer can be regularly formed in a recording area, a magnetic recording medium and a method for manufacturing the magnetic recording medium substrate. A plurality of recording areas wherein the magnetic layer is to be formed are formed on the surface of the disk-shaped magnetic recording medium substrate. The size of the recording area is an integral multiple of a lattice constant of a unit lattice of a single crystal structure constituting the magnetic layer. For instance, the width of a protruding section (3) to be used as the recording area is an integral multiple of the lattice constant of the unit lattice of the single crystal structure configuring the magnetic layer.

Abstract: The invention provides a magnetic recording medium, and a magnetic recording and reproducing apparatus. The magnetic recording medium includes a substrate 11, an under layer 12 formed on the substrate 11, a magnetic recording layer 13 formed on the under layer 12, and a protective layer 14 formed on the magnetic recording layer 13. The magnetic recording layer 13 is composed of a primary recording layer 14 and a secondary recording layer 15 which are mutually exchange-coupled. The primary recording layer 14 has magnetic grains and a nonmagnetic material that surrounds the magnetic grains, and has a perpendicular magnetic anisotropy. The secondary recording layer 15 is made of a material having a negative crystal magnetic anisotropy and its easy plane of the magnetization is a plane of the medium.

Abstract: According to one embodiment, a magnetic recording apparatus includes a magnetic recording medium including magnetically recordable recording tracks with a width L1, non-recording sections each provided between adjacent recording tracks, and a wide land track having a width L2 larger than the width L1 of the recording tracks, and a head slider including read and write heads.

Abstract: A data storage device uses a foil disk platter with significantly reduced inertia and weight as compared to the thick aluminum or glass disk platter in a typical hard disk drive. The reduced rotating inertia of the foil disk enables faster spin-up performance which can be used to reduce decrease the power consumed by the unit. In portable appliances that use disk drive storage devices battery life can be extended significantly and the unit can be made thinner and lighter. Certain parameters of the foil disk substrate may be determined, to provide improved control of disk flutter, from a range parameter defined by RANGE = ? ? ? R 2 Et 2 where ?=foil disk substrate mass density, R=foil disk substrate radius, E=Young's modulus of foil disk substrate, and t=foil disk substrate thickness. RANGE has dimensional units of s2/in2, and the magnitude of RANGE may be between 10?6 and 3(10?4).

Abstract: An apparatus may include a first magnetic layer, a first exchange break layer formed on the first magnetic layer, a second magnetic layer formed on the first exchange break layer, a second exchange break layer formed on the second magnetic layer, and a third magnetic layer formed on the second exchange break layer. The first magnetic layer has a first magnetic anisotropy energy, Hk1, the second magnetic layer has a second magnetic anisotropy energy, Hk2, and the third magnetic layer has a third magnetic anisotropy energy, Hk3. In some embodiments, Hk1?Hk2 is less than Hk2?Hk3. In some embodiments, the apparatus may be a perpendicular magnetic recording medium.

Abstract: In some embodiments, an article comprising a first magnetic recording layer, the first magnetic recording layer including a granular layer having a first magnetic anisotropy and a multi-layer stack adjacent the granular layer, the multi-layer stack comprising one or more substantially magnetic film layers alternating with one or more polarization conductor layers, wherein the multi-layer stack has a second magnetic anisotropy that is greater than the first magnetic anisotropy.

Abstract: A method and apparatus for writing magnetization states in a pair of magnetic layers of a multi-layer continuous magnetic recording medium and a method and apparatus for reading readback pulse shapes representing a magnetization state transition between such written magnetization states of a two-layer continuous magnetic recording medium. Writing each magnetization state includes selecting the magnetization state, determining a write current sufficient to write the magnetization state, and applying the write current to a magnetic write head to write the magnetization state by simultaneously writing associated magnetic states in each magnetic layer of the pair of magnetic layers. A readback pulse shape representing a written magnetization state transition is read.

Abstract: According to one embodiment, a bit patterned medium includes a substrate, and a magnetic recording layer disposed above the substrate and including patterns of protrusions. Each of the protrusions contains a plurality of crystal grains. An average distance between the crystal grains is 0.5 to 3.0 nm in each of the protrusions. The protrusions include first protrusions each having a length of 1 ?m or more in a radial direction of the medium and second protrusions each having a length in the radial direction shorter than the length of the first protrusion in the radial direction. Each of the first protrusions has a nucleation field Hn for magnetization reversal and a coercive force Hc satisfying the inequalities, Hn?1.5 kOe and 0.5 kOe?Hc?Hn?1.5 kOe.

Abstract: A protection layer containing carbon as a major component is deposited by plasma CVD. The protection layer has film quality such that, when a spectrum is obtained by excluding photoluminescence from a Raman spectrum in a wavenumber band from 900 cm?1 to 1800 cm?1 obtained by exciting the protection layer with an argon ion laser beam having a wavelength of 514.5 nm and the spectrum is subjected to waveform separation by the Gaussian function to split a D peak appearing around 1350 cm?1 and a G peak appearing around 1520 cm?1, the ratio Dw/Gw between a half width Dw of the D peak and a half width Gw of the G peak exceeds 0 and is not greater than 2.7.

Abstract: Disclosed is a magnetic recording/reproduction device 2 including: a recording/reproduction head 7; and a recording/reproduction head 7 for detecting a leakage magnetic field of each of the plurality of magnetic recording cells 1 so as to reproduce information, the recording/reproduction head 7 carrying out the recording on the magnetic recording medium 4 so that the magnetic recording medium 4 includes continuous recording regions that (i) satisfy Nmin?2 and that (ii) include a continuous recording region that satisfies N?n×Nmin, where N represents a number of magnetic recording cells 1 in a continuous recording region; Nmin represents a minimum value for N; and n represents a positive integer, the continuous recording regions each being a region on a reproduction track in which region magnetic recording cells 1 sharing an identical magnetization direction are sequentially arranged in a circumferential direction of the magnetic recording medium 4.

Abstract: A method and apparatus for writing magnetization states in magnetic islands of a multi-level patterned magnetic recording medium with more than two recording levels and a method and apparatus for reading readback waveforms representing written magnetization states of the magnetic islands in the multi-level patterned magnetic recording medium. Writing each magnetization state includes selecting the magnetization state, determining a write current sufficient to write the magnetization state, and applying the write current to a magnetic write head to write the magnetization state, including simultaneously writing associated magnetic states in each magnetic island of at least one pair of magnetic islands. Reading the readback waveform representing a written magnetization state is implemented through use of a magnetic read head and includes: identifying the written magnetization state by decoding the readback waveform; and displaying and/or recording the written magnetization state.

Abstract: This magnetic recording device is provided with a magnetic write head having a magnetic pole, and a magnetic recording medium having a plurality of data recording blocks. Each of the data recording blocks is formed with a plurality of write tracks and separated, in a write track width direction, from neighboring one of the data recording blocks with a writing exudation suppression section in between. With this configuration, a magnetic mutual interference of the adjacent data recording blocks at the time of a data rewriting process is avoided even when a mutual interval of the data recording blocks is narrowed, and a good recording state is maintained in each of the data recording blocks. Therefore, it is possible to achieve an improvement in a recording density, while realizing the good and brief data rewriting process for each of the data recording blocks.

Abstract: A magnetic recording medium (10) has a substrate (12) and a perpendicular magnetic recording layer (30) formed over the substrate (12). The perpendicular magnetic recording layer (30) has a granular layer (20) in which a magnetic signal is recorded and a continuous film layer (24) magnetically coupled to the granular layer (20). The continuous film layer (24) has hard magnetic portions (204) formed in positions corresponding to the recording regions where magnetic signals are recorded in the granular layer (20) and magnetic shield portions (202) formed between the hard magnetic portions (204), each having a magnetization curve whose slope is larger than those of the hard magnetic portions in the region where the applied magnetic filed is zero when the magnetization curve is measured, and each having a residual magnetic polarization smaller than those in the hard magnetic portions.

Abstract: According to one aspect of the present invention, provided is glass for use in substrate for information recording medium, which comprises, denoted as molar percentages, a total of 70 to 85 percent of SiO2 and Al2O3, where SiO2 content is equal to or greater than 50 percent and Al2O3 content is equal to or greater than 3 percent; a total of equal to or greater than 10 percent of Li2O, Na2O and K2O; a total of 1 to 6 percent of CaO and MgO, where CaO content is greater than MgO content; a total of greater than 0 percent but equal to or lower than 4 percent of ZrO2, HfO2, Nb2O5, Ta2O5, La2O3, Y2O3 and TiO2; with the molar ratio of the total content of Li2O, Na2O and K2O to the total content of SiO2, Al2O3, ZrO2, HfO2, Nb2O5, Ta2O5, La2O3, Y2O3 and TiO2 ((Li2O+Na2O+K2O)/(SiO2+Al2O3+ZrO2+HfO2+Nb2O5+Ta2O5+La2O3+Y2O3+TiO2)) being equal to or less than 0.28.

Abstract: A magnetic disk apparatus includes a magnetic disk that includes a plurality of zones in which a plurality of tracks are arranged for each of circumferences of a spiral, and gaps that are arranged between the zones to have a width a predetermined number of times larger than a track width and that are regions without providing recording bits; and a reproducing element that simultaneously makes an access to the recording bits contained in the tracks, reading information stored in the recording bits, wherein the number of the tracks is one or larger and a sum of one and the predetermined number or smaller in one of the zones.

Abstract: [Problem] The concentration distribution in a perpendicular direction of ions implanted in a magnetic recording layer of a perpendicular magnetic recording medium is made a suitable one corresponding to a layer implanted with ions.

Abstract: A patterned recording media is formed from a master template that includes a data area and a timing track area having a final timing track. In order to form the final timing track, a first timing track is etched into master template and tested for accuracy by comparing the angular position of the master template to the timing track. If errors are detected in the timing track, the errors are used to create additional timing tracks which are etched into the master template. This process of improving the timing track is repeated until a final timing track is formed that has errors below a predetermined level. The timing tracks formed prior to the final timing track are removed and the master template is used to make stampers which are used to make patterned media disks.

Abstract: A disk drive having a magnetic recording disk with a transition zone is described. A surface texture of the transition zone induces the head to fly at a greater height than when operating over a data zone, while transitioning the head to a landing zone to park.

Abstract: Described herein are various embodiments of an electronic information storage apparatus and an associated method and system. For example, according to one illustrative embodiment, a disk drive comprises a base and at least one disk that are rotatably attached to the base. The at least one disk can include a burnished and lubricant-free outer surface. The disk drive can also include an actuator coupled to the base. The actuator can comprise a read/write head that is positionable in a reading/writing relationship with the at least one disk to define a lubricant-free space intermediate the read/write head and the outer surface. The disk drive can further include a read/write head loading and unloading ramp that is attached to the base. The ramp can include a ramp surface that is positioned proximate a periphery of the at least one disk.

Abstract: An annular groove is provided to the rotary portion and/or the fixed portion in a bearing seal portion, and its cross section has a shape approximated by an arc. The annular groove is such that the relationship between the groove width W in a direction following the surface constituting a bearing seal portion and the groove depth Dg in a direction perpendicular to the surface constituting the bearing seal portion is Dg/W<0.4.

Abstract: A magnetic disk includes: a data recording region having first magnetic parts; the first magnetic parts being arranged in a circumferential direction in the nonmagnetic region and form tracks, and the tracks being arranged in a radial direction at a track pitch Tp; and a burst pattern region having burst patterns making a magnetic head follow the first magnetic parts, the burst patterns having second magnetic parts, the second magnetic parts forming base units arranged at a pitch Sp in a radial direction of the disk, the pitch Sp being more than twice as large as the track pitch Tp, the base units including a plurality of base units arranged in a circumferential direction of the disk, and the base units adjacent to each other in the circumferential direction being displaced from each other by the pitch Sp in the radial direction of the disk.

Abstract: Pre-patterned discrete track media for self-servo writing are described. Embodiments include land and groove patterns for two or more Integrated Servo sequence fields for each servo sector in which one of the Integrated Servo sequence fields is aligned with the data track and a second sequence is offset by one-half of a track width. The lands and grooves between the Integrated Servo sequence fields are preferably the same width as those between the data tracks to facilitate planarization. Alternative embodiments include a sync feature for each servo sector formed by a selected groove and/or land pattern as a marker for the start of the servo fields. Alternative embodiments include a bootstrap zone with servo patterns that are readable when DC-magnetized. Described methods of self-servowriting include ways to adapt to eccentricity and non-circularity of pre-patterned discrete tracks with respect to the head paths.

Abstract: It is possible to improve the recording and reproducing S/N ratio, the reproduction signal intensity, and the degree of high density recording. There are provided a plurality of recording tracks formed on a substrate, each recording track being formed of a magnetic material, and non-recording sections formed on the substrate, each non-recording section separating adjacent recording tracks, each recording track including a plurality of recording sections and connecting sections for connecting the recording sections adjacent thereto in a track longitudinal direction, and each connecting section having a cross-sectional area in a track width direction that is smaller than a cross-sectional area in a track width direction of adjacent recording sections.

Abstract: A patterned-media perpendicular magnetic recording disk has patterned servo regions and is nanoimprinted from a master mold made using directed self-assembly of block copolymers. The disk has patterned concentric circular data tracks of discrete data islands, with the tracks having a track pitch in the radial or cross-track direction. The disk also has patterned servo sectors extending generally radially across the patterned data tracks. The servo pattern is a chevron pattern of slanted or non-radial stripes that have a stripe pitch in the cross-stripe direction substantially equal to the track pitch. As a result of the method of making the master mold, the nanoimprinted disk has a chevron servo pattern with non-radial stripes that are magnetized segments of radial lines separated by nonmagnetic spaces.

Abstract: According to one embodiment, a magnetic recording medium includes a plurality of magnetic dots having a pattern formed by self organization. The density of magnetic dots in a peripheral portion of a central portion in a widthwise direction is higher than that of magnetic dots in the central portion at a burst portion of the magnetic recording medium.

Abstract: A slider assembly for supporting a recording element in operative relation to a flexible moving recording medium is disclosed. The slider may have a face including air bearing surfaces positioned toward the recording medium. A recording element may be in an air bearing surface near the trailing edge of the face, wherein there is no other slider or other supporting surface on an opposite side of the recording medium. A vacuum cavity may be formed in the face for creation of sub-ambient pressure to attract the slider toward the recording medium. An air bearing surface may be provided with a transverse pressure contour (TPC) along at least one of its edges for providing flying height control, with the TPC having a step geometry. A mounting device may mount the slider in a biased manner toward the recording medium and urge the slider toward the recording medium.

Abstract: A magnetic recording medium includes: a substrate; a recording layer that is formed on the substrate to have a grooved pattern; and a protection layer formed on the recording layer to fill in the grooved pattern, wherein the recording layer is defined to have a servo portion that retains servo data and a recording track portion that retains recording data, and wherein a first film thickness of the protection layer at the servo portion is larger than a second film thickness of the protection layer at the recording track portion by a thickness that is in a range from 1 nm to 10 nm.

Abstract: According to one embodiment, a magnetic recording medium includes a data region and a servo region adjacent to the data region and including a magnetic recording layer, the magnetic recording layer including first and second patterned regions adjacent to each other, the first patterned region including a first nonmagnetic matrix and first magnetic particles dispersed in the first nonmagnetic matrix and having magnetization oriented in a first direction, the second patterned region includes a second nonmagnetic matrix and second magnetic particles dispersed in the second nonmagnetic matrix and having magnetization oriented in a second direction opposite to the first direction, sizes of the first magnetic particles being smaller than sizes of the second magnetic particles.

Abstract: A magnetic recording-reproducing apparatus includes: a magnetic recording medium in which portions corresponding to track portions serve as recording areas and in which portions between the recording areas serve as non-recording areas; and a magnetic head having a main pole and a side shield disposed on both sides of the main pole in a cross-track direction. In the magnetic recording-reproducing apparatus, following inequality (I) is satisfied: S>Tw/2+Gw??(I) where Tw is a track width, Gw is a gap width, and S is a distance between the center of the main pole of the magnetic head and an edge on the main pole side of each of the side shields.

Abstract: A method of protecting information written to a recording medium includes magnetizing the recording medium to form a first magnetic pattern corresponding to information to be stored, and magnetizing the recording medium to form a protective magnetic pattern having a phase difference of 180° from the first magnetic pattern at a position adjacent to where the first magnetic pattern is formed, with adjacent bits of the first magnetic pattern opposite and the protective magnetic pattern opposite to each other.

Abstract: A defect inspection is performed for each of glass substrates by a surface defect detector. The distance from the center of the glass substrate to a detected defect, as a radius of a nonmagnetic region to be formed circular, is recorded along with an ID assigned to the glass substrate. Such defect information is recorded in a defect list using a printer or recorded in an RFID tag using an RFID writer. The defect list or the RFID tag is attached to a glass-substrate case. Each glass substrate and its defect information are in one-to-one correspondence and are provided to a customer as a magnetic disk manufacturer. Based on the obtained defect information, the customer manufactures magnetic disks each being a discrete track recording medium having the nonmagnetic region formed at the position where the defect is present.

Abstract: According to one embodiment, a servo area of a magnetic recording medium includes magnetic dots arrayed at a period L0. The magnetic dots include a plurality of magnetic dot regions divided in the cross track direction. A width Wm in the down track direction of the mth magnetic dot region from the innermost circumference and a number Nm of dot rows in the down track direction of the mth region meet a relationship represented by L0{Nm?3/2?0.3}?Wm?L0{Nm?3/2+0.

Abstract: When performing writing on a substrate applied with a resist by rapidly vibrating electron beam in a direction orthogonal to a radial direction of the substrate and X-Y deflecting the electron beam while rotating the substrate in one direction, a long element is written by scanning the electron beam with the middle position of a 2-bit signal length as the center position of the electron beam so as to completely fill the area of the writing length reduced by a predetermined ratio and an unwritten portion of predetermined width remaining on each side of the long element with respect to a final 2-bit signal length on a magnetic disk medium.

Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming on a magnetic recording layer a first hard mask, a second hard mask, a third hard mask and a resist, imprinting the resist with a stamper, removing a residue left in the recesses of the patterned resist, etching the third hard mask by use of the patterned resist as a mask, etching the second hard mask by use of the third hard mask as a mask, etching the first hard mask by use of the second hard mask as a mask, forming a pattern of the magnetic recording layer with ion beam irradiation, and removing the first hard mask by use of a remover liquid with higher reactivity to the metal material of the first hard mask than to a constituent element of the magnetic recording layer.

Abstract: A patterned magnetic recording medium, accessible by a magnetic recording head, including a plurality of tracks, a width direction of each track and that of the magnetic recording head being of a skew angle. The patterned magnetic recording medium includes a plurality of magnetic dots, each corresponding to a recording bit, formed on a non-magnetic material. The plurality of magnetic dots are arranged in a plurality of arrays, each array corresponding to one of the tracks. Every N adjacent magnetic dots of the array define a polygon, one side thereof being parallel to the corresponding track, and another side thereof being parallel to a direction corresponding to the skew angle of the corresponding track.

Abstract: A magnetic disk is protected by a bilayer. The bilayer is formed as an adhesion enhancing underlayer and a protective diamond-like carbon (DLC) overlayer. The underlayer is formed of an aluminum or alloyed aluminum oxynitride, having the general formula AlOxNy or MezAlOxNy where Mez symbolizes Tiz, Siz or Crz and where x, y and z can be varied within the formation process. By adjusting the values of x and y the adhesion underlayer contributes to such qualities of the protective bilayer as stress compensation, chemical and mechanical stability and low electrical conductivity. Various methods of forming the underlayer are provided, including reactive ion sputtering, plasma assisted chemical vapor deposition, pulsed laser deposition and plasma immersion ion implantation.

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 protective bilayer on a magnetic read/write head or magnetic disk is formed as an adhesion enhancing and corrosion resistant underlayer and a protective diamond-like carbon (DLC) overlayer. The underlayer is a transition metal oxynitride, having the general formula MeOxNy, where Me represents a single element or an alloy of the following transition metal elements: Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W, here x can be within the range between 0 and 3 and y is in the range between approximately 0 and 2. Adjusting the values of x and y contributes to such qualities of the protective bilayer as stress compensation, chemical and mechanical stability and low electrical conductivity. Methods of forming the adhesion layer, include reactive ion sputtering, plasma assisted chemical vapor deposition, pulsed laser deposition and plasma immersion ion implantation.

Abstract: A method for forming a protective bilayer on a magnetic read/write head or magnetic disk. The bilayer is formed as an adhesion enhancing underlayer and a protective diamond-like carbon (DLC) overlayer. The underlayer is formed of an aluminum or alloyed aluminum oxynitride, having the general formula AlOxNy or MezAlOxNy where Mez symbolizes Tiz, Siz or Crz and where x, y and z can be varied within the formation process. By adjusting the values of x and y the adhesion underlayer contributes to such qualities of the protective bilayer as stress compensation, chemical and mechanical stability and low electrical conductivity. Various methods of forming the underlayer are provided, including reactive ion sputtering, plasma assisted chemical vapor deposition, pulsed laser deposition and plasma immersion ion implantation.

Abstract: A magnetic recording medium comprises a data region for recording data and a servo region that is disposed adjacent to the data region and has recorded information for controlling a magnetic head. The data region has a pattern of dots separated from each other by grooves or nonmagnetic material. The servo region lacks the pattern of dots, and includes magnetic information written in a flat region. The magnetic recording medium can be formed by a method that does not need a separate process of writing servo information.

Abstract: A production method of a disk drive device includes: an assembling process of assembling a subassembly by incorporating at least a bearing unit in a hub in a clean room; a pouring process of pouring a lubricant in the bearing unit; a cleaning-liquid discharging process of discharging a cleaning liquid to the hub; a cleaning-liquid intake process of taking in the cleaning liquid discharged to the hub; and a sealing process of sealing the subassembly in a seal-material.

Abstract: Embodiments of the present invention provide a perpendicular magnetic recording medium having a substrate, a magnetic recording layer and a protective layer. The magnetic recording layer includes a perpendicular recording layer, a magnetic coupling layer and a writing assist layer. The perpendicular recording layer is a Co alloy layer containing an oxide disposed between the magnetic coupling layer and the substrate. The magnetic coupling layer is a ferromagnetic layer disposed between the perpendicular recording layer and the writing assist layer. The writing assist layer is a ferromagnetic layer disposed between the magnetic coupling layer and the protective layer. The saturation magnetization of the magnetic coupling layer is lower than the saturation magnetization of the perpendicular recording layer or the writing assist layer. The thickness of the magnetic coupling layer is 1 nm or more and 3 nm or less.

Abstract: Embodiments herein illustrate patterned servo data that is used to facilitate subsequent servo writing to a magnetic disk while allowing the patterned disk to be planarized with a relatively simple planarization process. One disk drive system includes a magnetic disk that is patterned with magnetic lands and nonmagnetic grooves. The magnetic disk also includes bootstrap bands that may be configured at an inner diameter of the magnetic disk. The magnetic lands of the bootstrap bands have varying sizes and are patterned as servo data having a uniform polarity of magnetization. The bootstrap bands have a width that is sufficiently narrow to support an air bearing surface of a slider. The data tracks are circumferentially configured proximate to the bootstrap bands. The slider reads the patterned servo data to facilitate writing of additional servo data in the data tracks.