Patents Assigned to Sharp Microeletronics Technology, Inc.
  • Patent number: 5914202
    Abstract: A method is providing for making a multi-level reticle which transmits a plurality of incident light intensities, which in turn, are used to form a plurality of thicknesses in a photoresist profile. A partially transmitting film, used as one of the layers of the reticle, is able to provide an intermediate intensity of phase shifted light. The intermediate intensity light has an intensity approximately midway between the intensity of the unattenuated light passing through the reticle substrate layer, and the totally attenuated light blocked by an opaque layer of the reticle. The exposed photoresist receives light at two intensities to form a via hole in the resist in response to the higher intensity light, and a connecting line to the via at an intermediate level of the photoresist in response to the intermediate light intensity. A method for forming the multi-level resist profile from the multi-level reticle is provided as well as a multi-level reticle apparatus.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: June 22, 1999
    Assignees: Sharp Microeletronics Technology, Inc., Sharp Kabushiki Kaisha
    Inventors: Tue Nguyen, Bruce Dale Ulrich, David Russell Evans