Patents by Inventor Ralph Feder

Ralph Feder 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).

  • High aspect ratio, high resolution mask fabrication
    Patent number: 4293374
    Abstract: A high aspect ratio collimating mask for use in ion beam epitaxy or ion implantation doping is formed through the use of damage-trail-forming materials which are irradiated through a mask and then etched. The high aspect ratio is obtained in part by the sequential formation of a plurality of spaced mask plates. The mask is useful in producing large scale integrated circuits by ion implantation during epitaxial growth of a crystal wafer.
    Type: Grant
    Filed: March 10, 1980
    Date of Patent: October 6, 1981
    Assignee: International Business Machines Corporation
    Inventors: Praveen Chaudhari, Ned J. Chou, Ralph Feder, Alan B. Fowler, James A. VanVechten
  • Fabrication of high aspect ratio masks
    Patent number: 4018938
    Abstract: A method of constructing masks characterized by a high aspect ratio. The method includes at least a single exposure of a mask by radiation which is transmitted by the substrate before impinging on the resist. In a specific embodiment the mask is partially completed and the already deposited mask modulates the radiation transmitted by the substrate before it exposes the resist.
    Type: Grant
    Filed: June 30, 1975
    Date of Patent: April 19, 1977
    Assignee: International Business Machines Corporation
    Inventors: Ralph Feder, Eberhard A. Spiller
  • Method for preparing positive resist image
    Patent number: 3984582
    Abstract: A positive resist image is produced by exposing, to radiation in a predetermined pattern, a polymeric material containing polymerized alkyl methacrylate units and polymerized monoethylenically unsaturated acid units. The exposed and unexposed areas are distinguished by their different respective abilities to be swelled in an appropriate swelling agent, and the swelled areas are removed by dispersal in a nonsolvent liquid.
    Type: Grant
    Filed: June 30, 1975
    Date of Patent: October 5, 1976
    Assignee: IBM
    Inventors: Ralph Feder, Ivan Haller, Michael Hatzakis, Lubomyr T. Romankiw, Eberhard A. Spiller