OVERLAY VERNIER WITH ABERRATION EFFECT OF EXPOSING LENS

摘要

PURPOSE: An overlay vernier with aberration effect of exposing lens is provided to accurately gauge the value of the image shift in actual pattern within a die by gauging the image shift of a line/space pattern, thereby accurately correcting the overlay to minimize misalignment. CONSTITUTION: An overlay vernier with aberration effect of exposing lens comprises a first pattern(30) presenting an outer box, a second pattern(40) presenting an inner box, and a third pattern(50) having line patterns and space patterns repeatedly arranged on the first and second patterns. The line width of the third pattern is within the range of -50%-+50% of the exposed light wavelength.