Abstract: A magnetic disk storage medium (10) includes a smooth non-magnetic substrate (11) having surface roughened by sputter-depositing a continuous nonmagnetic rough thin film ("texture film") (14) over the substrate. The sputter conditions and composition of the texture film (14) are chosen to give a desired roughness and areal density of asperities. A sputtered adhesion layer (12) and/or a sputtered capping layer (15) are included to control the growth of the texture film and to improve its mechanical properties, respectively. A non-magnetic underlayer, a magnetic layer and a protective layer are then sputtered sequentially over the roughened substrate.

Abstract: A method for manufacturing a magnetic disk includes the step of providing first and second magnetic layers on a substrate. The first magnetic layer comprises Co. The portion of the first magnetic layer comprising Cr, Ta, Ti, W, Zr or Hf, if any, is less than 7.5 atomic % of the first magnetic layer (and preferably less than 5 atomic %). The second magnetic layer also comprises Co, and more than 7.5 atomic % of the second layer is Cr, Ta, Ti, W, Zr or Hf (and preferably more than 10 atomic %). We have discovered that the first and second magnetic layers can be made very thin without having a great reduction in coercivity.

Abstract: A method for manufacturing a magnetic disk includes the step of providing first and second cobalt alloy layers on a substrate. The first cobalt alloy layer is non-ferromagnetic, and the second cobalt alloy layer is ferromagnetic. The non-ferromagnetic layer is deposited on an underlayer. The non-ferromagnetic cobalt alloy provides a better crystal structure for depositing the subsequent ferromagnetic layer and thereby improves its magnetic properties. However, because the first cobalt alloy layer is not ferromagnetic, it does not adversely affect the magnetic characteristics of the disk.

Abstract: An apparatus for variably texturing a first surface of a rigid-disk substrate having an annular inner recording head-landing zone and an annular outer data zone surrounding the head-landing zone is characterized by a stepped force-exerting cylindrical stepped roller which forces a movable tape having an abrasive containing slurry on its surface to variably texture the zones of the surface of the substrate. A method of variably texturing a surface of a rigid-disc substrate includes the steps of providing a movable abrasive-containing tape between the stepped cylindrical roller and disk substrate to force the tape against the substrate with greater pressure on a head landing zone than on a data zone.

Abstract: A method for manufacturing a magnetic disk comprises the step of depositing a metallic layer on a glass substrate and laser texturing the metallic layer. The magnetic disk is then completed by deposition of (a) an underlayer such as Cr or sputtered NiP, (b) a magnetic layer such as a Co or Fe alloy, and (c) a protective overcoat such as ZrO.sub.2, carbon or hydrogenated carbon. By providing the above-mentioned metallic layer, laser texturing can now be used in conjunction with glass substrates.

Abstract: Apparatus for placing covers (5, 8) on a cassette (1) and taking covers (5, 8) off a cassette (1) comprises an upper cover removal structure (100U), a lower cover removal structure (100L), and means for holding the cassette in place (170-176). The upper cover removal structure (100U) includes a central body portion (102), a pair of arms (104, 106) rotatably mounted at the end of the central body portion, and fingers (112, 114) located at the end of the arms (104, 106). The fingers (112, 114) can be moved up and down in a direction parallel to the main axis of the arms. The upper cover removal structure (100U) includes means for moving the upper cover removal structure (100U) toward or away from the cassette (1). The lower cover removal structure (100L) includes a central body portion and a pair of arms 156, 158 having fingers (190, 192) at the ends thereof. The arms can move inwardly or outwardly to grasp the bottom cover (8).

Abstract: A new magnetic alloy exhibits high Hc and Ms while exhibiting excellent corrosion resistance, thereby providing ideal physical properties for high density recording applications. Other parameters of the media, such as SNR, PW50, and S are at least maintained, if not also improved. The alloy contains cobalt and up to 10 at. % Ni, up to 20 at. % Pt, up to 10 at. % Ta, up to 10 at. % Ti, and optionally up to 6 at. % B. The ratio of the tantalum to titanium in the alloy is between 3:1 and 1:3. The alloy is deposited by vacuum deposition (typically sputtering) on a similarly deposited non-magnetic Ni alloy under layer. Nitrogen and/or oxygen may be introduced into the alloy during deposition to improve SNR. Other corrosion-resistant thin film alloys may also be obtained by the inclusion of Ta and Ti.

Abstract: Reflection of a generated radiation beam (e.g., laser) from a disk substrate during radiation-induced texturing such that the reflection interferes with the generated radiation beam is eliminated as follows: the beam path of the laser beam is passed through focusing optics to focus the beam to a spot on the substrate surface; the beam path is offset from the center of the focusing optics so that the focusing optics bend the beam path, and further so that the beam is angled from normal to the surface of the disk, for example by between 2 and 5 degrees; and that portion of the beam reflected by the disk surface is blocked by appropriate means prior to its impinging upon the source of the generated radiation beam.

Abstract: A carbon film for protecting a magnetic disk is sputtered by a DC magnetron sputtering method, with the addition of superimposed AC power on the DC power applied to the carbon target. When the carbon film is sputtered for extended period in a production sputtering machine, nodular growth occurs over the sputtering surface of the carbon target. Such nodules are variously called "warts" or "mushrooms" in the industry and they are detrimental to the productivity of the sputtering machine. The size and quantity of the nodules over the target surface increase as the target is sputtered longer, and because these region do not contribute to sputtering, the efficiency of the target decreases. As sputter efficiency decreases, power input must be increased to the target to make up for the loss in the effective sputtering area of the target. Eventually, the power input must be increased to a point where arcing occurs continuously and sputtering cannot be continued.

Abstract: This patent teaches a new method of roughening the surface of a magnetic recording medium in order to reduce the stiction and friction between a recording head and the medium to thereby improve mechanical reliability. During this method, the medium substrate is heated to form second phase precipitates which result in roughening of the medium surface. The medium roughness can be controlled by proper selection of the heating temperature and time and the substrate alloy. This results in improved contact-start-stop (CSS) performance of the medium. The method of the present invention allows for lower costs and potentially higher throughput than conventional texturing processes.

Abstract: A carbon film for protecting a magnetic disk is sputtered in the presence of hydrogen. If a sufficient amount of hydrogen is present in the sputtering chamber, the resulting carbon film will exhibit superior mechanical characteristics, i.e. an enhanced wear resistance during a contact-start-stop or drag test in a disk drive. Sputtering in the presence of hydrogen can be accomplished by either DC or RF magnetron sputtering, or DC or RF diode sputtering.

Abstract: A unitary one-piece plug is insertable into a magnetic data storage blank disk by a robot arm. The plug has a relatively large flange portion and grip knob on one end, a smaller diameter entry portion on the other end which passes through a central aperture in the disk. A cylindrical portion of less diameter than the entry portion forms a circumferential slot which rests on a bottom edge of the aperture in a vertically oriented disk when the plug is left in the disk aperture and the disk is mounted in a disk carrier for disk processing. The plug flange then blocks communication from one side to the other side of the disk. When the plug is lifted in the disk aperture by a robot arm the plug slot is captured by the upper edge of the disk aperture and permits the robot arm to move the disk with its plug to and from a disk cassette.

Abstract: A unitary one-piece plug is insertable into a magnetic data storage blank disk by a robot arm. The plug has a relatively large flange portion and grip knob on one end, a smaller diameter entry portion on the other end which passes through a central aperture in the disk. A cylindrical portion of less diameter than the entry portion forms a circumferential slot which rests on a bottom edge of the aperture in a vertically oriented disk when the plug is left in the disk aperture and the disk is mounted in a disk carrier for disk processing. The plug flange then blocks communication from one side to the other side of the disk. When the plug is lifted in the disk aperture by a robot arm the plug slot is captured by the upper edge of the disk aperture and permits the robot arm to move the disk with its plug to and from a disk cassette.