Patents by Inventor Leonhard Mader

Leonhard Mader 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).

  • Phase mask for projection lithography and method for the manufacture thereof
    Patent number: 5397664
    Abstract: A carrier of light-transmissive material has a mask pattern of light-absorbent material arranged thereon. The carrier comprises first regions and second regions that are not covered by the absorbent material. An optical thickness of the carrier in the first regions differs from an optical thickness in the second regions such that a phase difference of 180.degree..+-.60.degree. exists between light that has traversed the first regions and light that has traversed the second regions. For manufacturing the phase mask, the first regions are produced by isotropic etching of the light-absorbent material and the second regions are produced by anisotropic etching into the carrier.
    Type: Grant
    Filed: September 24, 1993
    Date of Patent: March 14, 1995
    Assignee: Siemens Aktiengesellschaft
    Inventors: Christoph Noelscher, Leonhard Mader
  • Phase mask for projection lithography and method for the manufacture thereof comprising a selectively etchable phase shift layer directly on substrate
    Patent number: 5284724
    Abstract: A carrier of light-transmissive material has a mask pattern of light-absorbent material arranged thereon. The carrier comprises first regions and second regions that are not covered by the absorbent material. An optical thickness of the carrier in the first regions differs from an optical thickness in the second regions such that a phase difference of 180.degree.+/-60.degree. exists between light that has traversed the first regions and light that has traversed the second regions. For manufacturing the phase mask, the first regions are produced by isotropic etching of the light-absorbent material and the second regions are produced by anisotropic etching into the carrier.
    Type: Grant
    Filed: March 11, 1991
    Date of Patent: February 8, 1994
    Assignee: Siemens Aktiengesellschaft
    Inventors: Christoph Noelscher, Leonhard Mader