Patent ID: 6071656
Filing Date: 2000-06-06
Classification: G03F

Abstract:
A photolithography technique, comprising:providing a chip, wherein the chip comprises a plurality of latitudinal scribe lines, a plurality of longitudinal scribe lines, and a plurality of chip alignment marks at intersections of the latitudinal scribe lines and the longitudinal scribe lines, wherein the latitudinal scribe lines and the longitudinal scribe lines divide the chip into a plurality of effective and non-effective dies, and the chip further comprises a plurality of shots;providing a mask comprising a plurality of mask alignment marks corresponding to chip alignment marks of the chip;aligning the chip alignment marks of the chip with the mask alignment marks of the mask;selecting at least three of the chip alignment marks close to the effective dies in the shots to detect a focus and determine a focal plane of each shot to level each shot; andperforming an exposure process on the shots.