Optical proximity correction method
AssigneeZarlink Semiconductor Inc.
InventorsBrian Martin, Christine Wallace
Life of this patent
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Abstract
A method of carrying out optical proximity correction in the design of a reticle for exposing a photoresist of a wafer in photolithography using a lens having a focal plane, the method including generating a dense-isolated offset focus/exposure matrix, containing dense-isolated offset values, being the difference between values of linewidth for dense and isolated lines, as a function of focal plane position, for each of a plurality of different exposures, selecting from among the contours of the dense-isolated offset focus/exposure matrix for each different exposure, the flattest contour, and carrying out optical proximity correction on the basis that the exposure will be the exposure corresponding to said flattest contour.
Claims10
A method of carrying out optical proximity correction in the design of a reticle for exposing a photoresist on a substrate in photolithography using a lens having a focal plane, the method including the steps of:
- generating a dense-isolated offset focus/exposure matrix, containing dense-isolated offset values, being the difference between values for the linewidth of dense and isolated lines printed on said substrate, as a function of focal plane position, for each of a plurality of different exposures;
- selecting from among the contours of the dense-isolated offset focus/exposure matrix for each different exposure, the flattest contour, being the contour which is flattest in terms of variation of the dense-isolated offset over the range of focal plane positions of interest;
- and
- carrying out optical proximity correction on the basis that the exposure will be a selected exposure corresponding to said flattest contour.
Dependencies are inferred from the claim text.