Patent ID: 6596448
Filing Date: 2003-07-22
Classification: G03F

Abstract:
A phase error monitor pattern for monitoring phase errors in an alternating phase shift mask, wherein the phase error monitor pattern comprises an alternating phase shift pattern and a modification pattern, such that:the alternating phase shift patterns are located at peripheries of the alternating phase shift mask, the modification patterns are located at peripheries of a modification mask, the alternating phase shift mask and the modification mask are used in sequence in a same photo-exposure operation, and positions of the alternating phase shift patterns and positions of the modification patterns correspond to each other; the alternating phase shift pattern further includes a plurality of first non-transparent regions as well as a plurality of phase shift regions and a plurality of transparent regions alternating between the non-transparent regions, wherein every pair of first non-transparent regions corresponding to sides of each phase shift region forms a pair; and the modification pattern further includes a plurality of second non-transparent regions, wherein each second non-transparent region corresponds in position to a region in a first side of a pair of first non-transparent regions, and a width of each second non-transparent region is greater than a width of any one of the first non-transparent regions.