Patents by Inventor Richard H. Ahlert

Richard H. Ahlert has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5828532
    Abstract: A thin film lead structure resistant to resistance increase phenomenon resulting from contamination by mobile impurities. A thin film lead is disposed proximate to a getter layer material having a higher affinity for mobile impurities that the thin film lead. The getter layer material captures mobile impurities and prevents their migration into the thin film lead. The getter layer material may be formed over and in contact with the thin film lead, may be encapsulated within the thin film lead, or both. The getter layer material comprises a rare earth metal selected from the group consisting of yttrium, scandium, lanthanum, cerium, praseodymium, neodymium, samarium, gadolinium, terbium, dysprosium, holmium, erbium, and ytterbium. The thin film lead is preferably tantalum, but may be selected from the group consisting of niobium, vanadium, chromium, molybdenum, tungsten and iron. An alternate embodiment of the invention includes a transition metal comprising titanium, zirconium, or hafnium as the getter layer.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: October 27, 1998
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Michael A. Parker
  • Patent number: 5552204
    Abstract: A significantly thinner boron carbide overcoat layer is provided for a magnetic disk which has the same durability as thicker prior art overcoat layers for protecting an underlying magnetic layer. By employing adhesion layers selected from the group consisting of Ge, Ru, WTiSi, WTi, Si, and Y between the magnetic layer and the overcoat layer, the durability of the overcoat layer is significantly increased over a single overcoat layer of B4C. Certain process steps in the making of the B4C overcoat layer still further enhance the durability of the B4C overcoat layer by maintaining the disk or substrate specimen at a floating potential in a plasma chamber and employing low levels of argon pressure and sputtering wattage.
    Type: Grant
    Filed: January 13, 1995
    Date of Patent: September 3, 1996
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Muhammad I. Ullah, Richard D. Umphress
  • Patent number: 5492775
    Abstract: A high-density recording media comprising longitudinally oriented polycrystalline barium ferrite exhibits large coercivity, corrosion resistance, high hardness and durability. Films are prepared by on-axis sputtering at ambient temperatures from stoichiometric targets followed by a post-deposition anneal at approximately 850.degree.C. to induce crystallization. Crystallization yields a magnetic film with large in-plane remanence and a fine scale texturing that greatly improves the tribological performance of barium ferrite disks. Exceptional durability can be achieved on disks without overcoats. Grain sizes as small as 200 .ANG. are produced by doping with small amounts of Cr.sub.2 O.sub.3 or other additives. Coercivities greater than 4000 Oe are achieved even in small grain films.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: February 20, 1996
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Todd L. Hylton, Michael A. Parker, Muhammad I. Ullah
  • Patent number: 5227212
    Abstract: An improved CoPt based or CoNi based alloy magnetic recording disk for horizontal recording has a magnetic recording layer which is a laminated structure of relatively thin magnetic alloy films separated by relatively thin non-magnetic spacer films. The resulting laminated disk structure has substantially decreased intrinsic media noise at high linear recording densities. A magnetic recording disk drive uses the low noise laminated disk and and a magnetoresistive read sensor to provide a disk drive with significantly reduced noise in the data readback signal.
    Type: Grant
    Filed: August 2, 1991
    Date of Patent: July 13, 1993
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Steven E. Lambert, Ian L. Sanders
  • Patent number: 5149409
    Abstract: In the fabrication of thi film cobalt alloy magnetic recording disks by sputter-deposition, the coercivity of the disks can be selectively varied by introducing a predetermined amount of hydrocarbon gas, such as methane, into the argon-based sputtering atmosphere. The flow rate of the hydrocarbon gas into the sputtering chamber is directly related to the coercivity of the resulting disks. This permits the coercivity of the disks to be controlled without the necessity of changing the composition of the cobalt alloy sputtering targets, and without the necessity of changing the thickness of an underlying between the disk substrate and the magnetic layer. The use of hydrocarbon gas in the reactive sputtering of the cobalt alloy magnetic layer in the disks does not affect the intrinsic media noise of the disks, thus allowing for the manufacturing of disks with high signal-to-noise ratio (SNR) of the readback signal.
    Type: Grant
    Filed: January 11, 1991
    Date of Patent: September 22, 1992
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Steven E. Lambert
  • Patent number: 5051288
    Abstract: An improved CoPt based or CoNi based alloy magnetic recording disk for horizontal recording has a magnetic recording layer which is a laminated structure of relatively thin magnetic alloy films separated by relatively thin non-magnetic spacer films. The resulting laminated disk structure has substantially decreased intrinsic media noise at high linear recording densities.
    Type: Grant
    Filed: March 16, 1989
    Date of Patent: September 24, 1991
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Steven E. Lambert, Ian L. Sanders
  • Patent number: 5030494
    Abstract: A thin film metal alloy magnetic recording disk has an improved protective overcoat which is both wear resistant and which creates a low level of stiction in a rigid disk file. In a preferred embodiment the overcoat is a film of essentially amorphous carbon or hydrogen-containing carbon with relatively small amounts of additives of iron (Fe), tungsten (W) or tungsten-carbide (WC). The structure of the overcoat is a relatively smooth planar carbon surface with discrete clusters of the additives which project slightly above the smooth carbon surface. The specific additives to the carbon overcoat improve the wear resistance of the disk and permit the sliders to contact the disks in contact start/stop (CSS) operation without damage to any of the disk file components.
    Type: Grant
    Filed: January 26, 1989
    Date of Patent: July 9, 1991
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Kwang K. Kim, Ian L. Sanders, Anthony W. Wu
  • Patent number: 4749628
    Abstract: A vertical magnetic recording medium is formed of multiple layers, each layer comprising a cobalt-platinum (CoPt) magnetic film formed on a hexagonal-close-packed (HCP) necleating film. The thickness of each CoPt film in each layer is sufficiently thin to assure that the film has perpendicular magnetic anisotropy. The magnetic properties of the multilayered magnetic film structure can be varied by varying the thickness of the individual films and the number of layers.
    Type: Grant
    Filed: April 29, 1986
    Date of Patent: June 7, 1988
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Grace S. Lim
  • Patent number: 4654276
    Abstract: An improved cobalt-platinum (CoPt) thin film metal alloy media for horizontal magnetic recording has a coercivity substantially greater than prior CoPt thin film metal alloy media. A tungsten underlayer between the substrate and the CoPt magnetic layer improves the coercivity above that of media wiht conventional underlayers, such as chromium. The coercivity of the CoPt layer can be increased even further if the CoPt film is deposited in such a manner as to form an intermetallic compound of Co.sub.3 W in the interface region between the tungsten underlayer and the CoPt magnetic layer. The tungsten underlayer also improves the magnetic properties of the media when the magnetic layer is an alloy of cobalt-platinum-chromium (CoPtCr).
    Type: Grant
    Filed: April 29, 1986
    Date of Patent: March 31, 1987
    Assignee: International Business Machines Corporation
    Inventors: Richard H. Ahlert, James K. Howard, Grace S. Lim