Patent ID: 8755034
Filing Date: 2014-06-17
Classification: G03B,G03F

Abstract:
1. A method to determine an exposure start position and orientation comprising: loading a substrate, on which is patterned at least one alignment mark of a first set of alignment marks of a first pattern layer, on a moving table; exposing the substrate, using maskless lithography, to form at least one alignment mark of a second set of alignment marks of a second pattern layer on the substrate; measuring a position of the at least one alignment mark of the first set of alignment marks and a position of the at least one alignment mark of the second set of alignment marks on the substrate; acquiring a relative orientation difference between a desired exposure start orientation and an obtained exposure start orientation using the measured positions of the at least one alignment mark of the first set of alignment marks and the at least one alignment mark of the second set of alignment marks; acquiring a relative position difference between a desired exposure start position and an obtained exposure start position using the measured positions of the at least one alignment mark of the first set of alignment marks and the at least one alignment mark of the second set of alignment marks; determining an exposure start position and orientation compensated using the relative position difference and the relative orientation difference; compensating for the exposure start orientation of the substrate using the relative orientation difference; repeatedly loading and exposing the substrate after compensating for the exposure start orientation of the substrate; and measuring a position of the at least one alignment mark of the first set of alignment marks and a position of the at least one alignment mark of the second set of alignment marks on the substrate after completion of the repeated exposure of the substrate.