Patents by Inventor Michael R. Gulett

Michael R. Gulett 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: 4859573
    Abstract: A process for selectively hardening a surface layer of a polymeric photoresist to make such surface layer opaque and insoluble in photoresist carrier solvents, where such selectivity is coextensive with the polymeric/monomeric pattern created in the photoresist. Representative hardening processes include controlled exposure to certain gas plasmas, ion bombardment, or irradiation by ultraviolet radiation of chosen wavelength range. The selectively hardened polymeric regions act as a barrier to the carrier solvent in which the polymer film is laid down and to the developer subsequently employed to remove the monomeric regions. The hardened polymeric regions further exhibit an actinic radiation barrier property preventing radiation depolymerization. In one form the process may be used in a two-layer photoresist structure, where the pinhole-covering thicker second layer is laid down and exposed before developing the monomeric regions of the thinner first layer.
    Type: Grant
    Filed: August 21, 1987
    Date of Patent: August 22, 1989
    Assignee: NCR Corporation
    Inventors: George Maheras, Hubert O. Hayworth, Michael R. Gulett
  • Patent number: 4354307
    Abstract: In the disclosed method, dopant atoms of a first conductivity type are implanted into the surface of a semiconductor substrate to form a channel region of each transistor having a relatively high dopant density at a predetermined depth below the surface and a substantially lower dopant density at the surface. This eliminates reachthrough in the channel without adversely increasing the channels threshold voltage. Thereafter, dopant atoms of a second conductivity type are implanted into the substrate to form source and drain regions adjacent to the channels having a depth of less than 0.3 .mu.m below the surface. This minimizes the radius of curvature and corresponding depletion width at the respective junctions with the channel. Subsequently, a patterned insulating layer is formed on said surface at temperatures that are far below the insulating layer's flow point. This avoids diffusing the distribution of the implanted dopant atoms.
    Type: Grant
    Filed: December 3, 1979
    Date of Patent: October 19, 1982
    Assignee: Burroughs Corporation
    Inventors: Mark A. Vinson, Rakesh Kumar, Norman W. Jones, Michael R. Gulett
  • Patent number: 4330569
    Abstract: A method of conditioning a nitride surface by treating it with ionized oxygen is disclosed. The nitride surface is placed in a vacuum and treated with the ionized oxygen for a period of time sufficient to condition the nitride for subsequent processing steps. The ionized oxygen treatment is performed substantially at ambient temperature. The conditioning method is included in a process for improving the adhesion characteristics of a photoresist film to a silicon nitride surface. A liquid solution of hexamethyldisilazane is applied to the conditioned nitride surface. Thereafter, a photoresist is applied, exposed through a photographic mask and developed in a known manner for the purpose of forming a photoresist masking film pattern. The photoresist film pattern typically serves as a mask during an etching process in which areas not covered by photoresist are removed by a suitable etching solution.
    Type: Grant
    Filed: October 10, 1980
    Date of Patent: May 18, 1982
    Assignee: NCR Corporation
    Inventors: Michael R. Gulett, Murray L. Trudel, John K. Stewart, Jr.
  • Patent number: 4075367
    Abstract: A method of providing improved adherence of photoresist to a silicon nitride layer on a semiconductor wafer by first preparing a heated solution of trichlorophenylsilane, immersing the nitride coated wafer in the trichlorophenylsilane solution, drying and baking the wafer prior to the application of the photoresist.
    Type: Grant
    Filed: March 18, 1976
    Date of Patent: February 21, 1978
    Assignee: NCR Corporation
    Inventor: Michael R. Gulett