Patents Assigned to Lawrence Berkeley Laboratory, University of CA
  • Patent number: 5612986
    Abstract: Methods for forming X-ray images having 0.25 .mu.m minimum line widths on X-ray sensitive material are presented. A holgraphic image of a desired circuit pattern is projected onto a wafer or other image-receiving substrate to allow recording of the desired image in photoresist material. In one embodiment, the method uses on-axis transmission and provides a high flux X-ray source having modest monochromaticity and coherence requirements. A layer of light-sensitive photoresist material on a wafer with a selected surface is provided to receive the image(s). The hologram has variable optical thickness and variable associated optical phase angle and amplitude attenuation for transmission of the X-rays. A second embodiment uses off-axis holography. The wafer receives the holographic image by grazing incidence reflection from a hologram printed on a flat metal or other highly reflecting surface or substrate.
    Type: Grant
    Filed: September 22, 1995
    Date of Patent: March 18, 1997
    Assignee: Lawrence Berkeley Laboratory, University of CA
    Inventors: Malcolm S. Howells, Chris Jacobsen