Patents by Inventor Ralph S. Keen

Ralph S. Keen 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: 4887144
    Abstract: A process for forming a topside substrate contact in a trenched semiconductor structure. A trench (24, 26) is etched into a P- block of substrate (10) material. The trench (24, 26) is filled with silicon dioxide, and then the substrate material (10) circumscribed by the trench (24, 26) is removed to form a well. A subcollector (48) is implanted in the well of the P. substrate. Epi material (50) is grown in the well to the top of the silicon dioxide-filled trench. A device (59) is formed in the epi (50). Ohmic contacts (70) are formed on the topside of the substrate to the device (59) within the well, and to the P- substrate itself outside the trench.
    Type: Grant
    Filed: February 27, 1987
    Date of Patent: December 12, 1989
    Assignee: Texas Instruments Incorporated
    Inventors: Brian E. Cook, Ralph S. Keen
  • Patent number: 4774396
    Abstract: An apparatus for generating infrared radiation is provided including an electrical heating element that is able to withstand very high, continuous-use temperatures, surrounding or surrounded by a non-conductive material containing dopants of refractory metal oxides, rare earth oxides, or combinations of both. The material may be shaped about the heating element so that the infrared radiation emissions may be focused and/or directed in a desired manner.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: September 27, 1988
    Assignee: FabAid Incorporated
    Inventors: Herbert W. Salit, Ralph S. Keen, Jr., Robert M. Koeller
  • Patent number: 4209894
    Abstract: A programmable read only memory array of the fusible link type employs a small part of a deposited metal film as a fuse. The film is covered by a protective glaze which seals the surface of the semiconductor chip to avoid deterioration of the transistors or other components. In order to minimize heat loss to the semiconductor substrate when programming, and to provide a cavity beneath the protective glaze, the metal film is raised above the surface at the position of the fusible link. This is accomplished by a segment of photoresist applied prior to metal deposition, then removed with photoresist stripper after the metal is patterned.
    Type: Grant
    Filed: April 27, 1978
    Date of Patent: July 1, 1980
    Assignee: Texas Instruments Incorporated
    Inventor: Ralph S. Keen