Patents by Inventor Joel Ollendorf

Joel Ollendorf 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).

  • Protective circuit for MOS devices
    Patent number: 4100561
    Abstract: The circuit protects the oxide of MOS devices from destructive breakdown by limiting the potential difference which can exist between two circuit nodes. By forming a protective circuit between each pair of nodes in the circuit, the range of voltages which can exist between any two nodes is predetermined, and the range can be fixed to prevent damage to the MOS devices. The protective circuit comprises a pair of diodes, a resistor, and a bipolar transistor.
    Type: Grant
    Filed: May 24, 1976
    Date of Patent: July 11, 1978
    Assignee: RCA Corp.
    Inventor: Joel Ollendorf
  • Method of performing contactless photolithography
    Patent number: 4088406
    Abstract: A semiconductor wafer vacuum chuck used as part of a photographic wafer-alignment machine for performing contactless photolithography has integral spacer means disposed on a substantially planar surface thereof for mechanically maintaining a fixed distance between portions of a wafer positioned adjacent the spacer means and the surface of the wafer chuck, whereby a controlled separation is provided between a surface of the wafer and a photographic mask overlying the surface of the wafer upon the application of a vacuum to the surface of the wafer chuck.
    Type: Grant
    Filed: November 15, 1976
    Date of Patent: May 9, 1978
    Assignee: RCA Corporation
    Inventors: Joel Ollendorf, Frank J. Cestone
  • Semiconductor wafer chuck with built-in standoff for contactless photolithography
    Patent number: 4006909
    Abstract: A semiconductor wafer vacuum chuck used as part of a photographic wafer-alignment machine for performing contactless photolithography has integral spacer means disposed on a substantially planar surface thereof for mechanically maintaining a fixed distance between portions of a wafer positioned adjacent the spacer means and the surface of the wafer chuck, whereby a controlled separation is provided between a surface of the wafer and a photographic mask overlying the surface of the wafer upon the application of a vacuum to the surface of the wafer chuck.
    Type: Grant
    Filed: April 16, 1975
    Date of Patent: February 8, 1977
    Assignee: RCA Corporation
    Inventors: Joel Ollendorf, Frank J. Cestone