Source optimization by assigning pixel intensities for diffractive optical element using mathematical relationship

摘要

A system and method for optimizing an illumination source to print a desired pattern of features dividing a light source into pixels and determining an optimum intensity for each pixel such that when the pixels are simultaneously illuminated, the error in a printed pattern of features is minimized. In one embodiment, a method includes selecting a pattern of layout features by determining one or more periodic patterns of features that occurs in the layout database, defining a mathematical relationship between pixel intensities produced by a diffractive optical element and the selected pattern of features, where the mathematical relationship includes a heavier weighting for the periodic patterns of features, and assigning pixel intensities for the diffractive optical element using the mathematical relationship, where the pixel intensities are calculated to print the periodic features with greater image fidelity in proportion to the heavier weighting.

主权项

1. A computer-readable storage medium storing a sequence of instructions that when executed by a computer causes the computer to perform a method, the method comprising:
selecting a pattern of features in a layout database to be created on a wafer, wherein the selecting comprises determining that the pattern of layout features in the layout database occurs in an array; defining a mathematical relationship between one or more pixel intensities produced by a diffractive optical element and the selected pattern of features; and assigning pixel intensities for the diffractive optical element using the mathematical relationship, the pixel intensities being calculated to produce an image of the selected pattern of features on the wafer with greater image fidelity than other features in the layout database.