Method and apparatus for increasing the resolution power of projection lithography exposure system

  • US 5,638,211 A
  • Filed: 06/10/1994
  • Issued: 06/10/1997
  • Est. Priority Date: 08/21/1990
  • Status: Expired due to Term
First Claim
Patent Images

1. An exposure apparatus comprising:

  • an illumination optical system for irradiating an illuminating light from a light source on a mask,a projection optical system for projecting an image of a pattern formed on said illuminated mask onto a substrate, andan aperture member arranged at the Fourier transform plane within said illumination optical system with respect to said pattern of said mask or a position near thereto, said aperture member being located between said mask and said light source within said illumination optical system that produces such light, said aperture member being provided with at least two separate localized areas having a higher light transmittance than portions of said aperture member surrounding said areas and being arranged at positions spaced from an optical axis of said illumination optical system by a distance corresponding to a fineness of said pattern, such that one component of a first beam from a first one of said areas passes through said projection optical system along substantially a same path as one component of a second beam from a second one of said areas, and such that another component of said first beam passes through said projection optical system along substantially a same path as another component of said second beam.

View all claims
    ×
    ×

    Thank you for your feedback

    ×
    ×