Patents by Inventor Roger H. French

Roger H. French 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: 5459002
    Abstract: Transmissive embedded phase shifter-photomask blanks are disclosed which comprise an optically inhomogeneous attenuating film which has a transmission of at least 0.001 and consists essentially of a combination of a metallic component and a dielectric component. One surface of the film has a higher content of metallic component than the other surface and the profile of change in extinction coefficient is gradual through the film thickness. The profile of change in extinction coefficient and the film thickness are selected to provide a phase shift of about 180.degree. (or an odd multiple thereof) at a selected wavelength.
    Type: Grant
    Filed: March 28, 1994
    Date of Patent: October 17, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Hakki U. Alpay, Roger H. French, Franklin D. Kalk
  • Patent number: 5415953
    Abstract: Transmissive embedded phase shifter-photomask blanks are disclosed which comprise an optically inhomogeneous attenuating film which has a transmission of at least 0.001 at the lithographic wavelength and consists essentially of a combination of multiple components with one of the components having a higher absorbance than another at the lithographic wavelength, One depth from a surface of the films has a higher content of the higher absorbing component than another depth and the profile of change in refractive index and/or extinction coefficient is gradual through the film thickness, Said profile(s) of change and the film thickness are selected to provide a phase shift of about 180.degree. (or an odd multiple thereof) at a selected lithographic wavelength.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: May 16, 1995
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Hakki U. Alpay, Roger H. French, Franklin D. Kalk
  • Patent number: 5393465
    Abstract: A composition for making fired dielectric layers which is especially suitable for laser scribing consisting essentially of finely divided particles of dielectric glass, inorganic filler having a refractive index higher than the glass and cobalt oxide, all being dispersed in organic medium. The composition can be in the form of either thick film paste or green tape.
    Type: Grant
    Filed: December 13, 1993
    Date of Patent: February 28, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Lorri P. Drozdyk, Roger H. French, Kenneth W. Hang, Arvind Halliyal