Patents by Inventor David Bruce Fraser

David Bruce Fraser 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: 4046660
    Abstract: Substrate heating during sputter coating, due to charged particles, is controlled by the use of an auxiliary magnet in the vicinity of the substrate. The magnet is arranged to either increase this charge particle flux, in situations in which additional heating is desired, or reducing this charge particle flux in situations in which heating is detrimental (e.g., the sputter coating of heat sensitive substrates such as polymer films).
    Type: Grant
    Filed: December 29, 1975
    Date of Patent: September 6, 1977
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: David Bruce Fraser
  • Patent number: 4039698
    Abstract: A method is disclosed for making precisely patterned platinum films in the manufacture of integrated circuit devices. The method calls for the deposition of a film of a platinum compound, whose heat of formation is in the range of from -100 to +10 Kcal/mole, patterning the film, and thermally reducing the patterned film to platinum metal.
    Type: Grant
    Filed: January 23, 1976
    Date of Patent: August 2, 1977
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: David Bruce Fraser, Alfred Urquhart MacRae
  • Patent number: 4022930
    Abstract: The specification describes a procedure for multilevel metallization of semiconductor integrated circuits in which the severity of the step formed by the edges of the first level pattern and the intermediate insulator over which the second level metallization pattern extends is reduced by beveling the edge. The bevel occurs during selective etching of the first level metal as a consequence of depositing the first level metal over a range of diminishing temperatures. Metal layers, notably aluminum, deposited in this way exhibit a differential etch rate such that the layer etches more slowly as etching proceeds through the thickness of the layer. Bevels of the order of 30.degree. to the horizontal can be produced in this way.
    Type: Grant
    Filed: May 30, 1975
    Date of Patent: May 10, 1977
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: David Bruce Fraser
  • Patent number: 3975252
    Abstract: High-resolution sputter etching of a relatively thick layer (of, for example, gold) by directly utilizing a relatively thin layer of resist as a sputter-etching mask is often not feasible. In such a case, it is known to use a sputter-etching mask made of an etch-resistant material such as titanium interposed between the resist and the relatively thick layer. In accordance with the invention, patterning of the titanium is achieved by a technique of sputter etching in a halocarbon atmosphere.
    Type: Grant
    Filed: March 14, 1975
    Date of Patent: August 17, 1976
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: David Bruce Fraser, David Yuan Kong Lou
  • Patent number: 3949131
    Abstract: In high resolution lithography, resolution impairment sometimes occurs due to dust collecting on the mask. The dust is often attracted to the mask by static electricity. The solution proposed is to coat the entire photomask with a transparent, electrically conductive coating. The coating is electrically grounded to drain static charge. Conductive materials are often used for lithographic masks, but the patterns cannot be grounded effectively because there are island regions in the pattern.If the pattern is itself conducting, there is the added option of applying the antistatic layer under the pattern.If the pattern is formed of a photographic emulsion of a patterned photoresist, it is protected from damage and wear in handling by the harder conductive coating.
    Type: Grant
    Filed: June 19, 1974
    Date of Patent: April 6, 1976
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventor: David Bruce Fraser