Patents by Inventor Xiaoding Ma

Xiaoding Ma 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: 6392244
    Abstract: Stable operation of an ion beam deposition (IBD) station forming part of a multi-station apparatus and formation therein of a tribologically robust DLC-type i-C:H ultra-thin protective overcoat for high recording density magnetic media are achieved by pulsing (i.e., limiting) the flow of a hydrocarbon source gas to the ion beam source to deposition intervals between substrate transfer/pressure cycling. Embodiments include utilizing a circularly-shaped, closed drift, end Hall type ion beam source as part of a multi-process station apparatus, wherein undesirable arcing of the ion beam source during substrate transfer is eliminated, or at least substantially reduced, as a result of the pulsed supply of hydrocarbon source gas to the ion beam source.
    Type: Grant
    Filed: August 18, 1999
    Date of Patent: May 21, 2002
    Assignee: Seagate Technology LLC
    Inventors: Kevin J. Grannen, Xiaoding Ma, Jing Gui
  • Patent number: 6312798
    Abstract: Ion beam-deposited, nitrogen-doped C:H films having substantially lower resistivities than undoped ion beam-deposited C:H films and suitable for use as hard, abrasion-resistant overcoat layers for magnetic recording media, such as hard disks, are formed by supplying a mixture of hydrocarbon and nitrogen gases to an ion beam generator. Nitrogen atom content of the films is controlled to within from about 5 to about 25 at. % by appropriate selection of the ratio of hydrocarbon gas flow to nitrogen gas flow. The resultant IBD i-C:HN films exhibit a reduced tendency for charge build-up thereon during hard disk operation by virtue of their lower resistivity vis-à-vis conventional a-C:H materials.
    Type: Grant
    Filed: September 21, 1999
    Date of Patent: November 6, 2001
    Assignee: Seagate Technology LLC
    Inventors: Xiaoding Ma, Kevin J. Grannen, Jing Gui, Jeffrey A. McCann, Mark A. Shows
  • Patent number: 6286453
    Abstract: A device for reducing the contamination of a disc being coated during an ion beam deposition process. The ion beam deposition process is performed in a chamber having an upper portion and a lower portion with the disc being disposed in the lower portion of the chamber. An ion source is introduced into the lower chamber for generating an ion beam for depositing ions on the disc. In the upper portion of the chamber is a pump for creating negative pressure in the chamber. A portion of the ion beam contacts the pump forming contaminants on the pump which cause the contamination of the disc. A baffle assembly is disposed in the chamber between the pump and the ion source. Said baffle assembly includes a baffle that reduces the portion of the ion beam contacting said pump thereby reducing the forming of contaminants on the pump.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: September 11, 2001
    Assignee: Seagate Technologies, Inc.
    Inventors: Kevin John Grannen, Jeffrey Arthur McCann, Xiaoding Ma, Jing Gui, Mark Anthony Shows