Mask reticle

A mask, comprising a first boundary area and a plurality of exposure pattern areas, the plurality of exposure pattern areas being arranged in an array, the first boundary area including a region surrounding the plurality of exposure pattern areas;

• wherein in the first boundary area is disposed a plurality of first overlay mark units, each of which includes a plurality of overlay marks, the first boundary area is provided with transversal and longitudinal first boundary lines corresponding to the plurality of exposure pattern areas arranged in an array, and the plurality of overlay marks are sequentially arranged along extension directions of adjacent transversal or longitudinal first boundary lines;
• and wherein
• the plurality of first overlay mark units are symmetric in pairs with a central line of the mask reticle as a symmetric axis, and two mutually symmetric first overlay mark units form an overlay mark set;
• arrangement direction of the overlay marks in one of the first overlay mark units in the same overlay mark set is parallel to arrangement direction of the overlay marks in another one of the first overlay mark units, and, on the arrangement directions of the overlay marks, one overlay mark in the first overlay mark units is displaced with respect to another overlay mark in the first overlay mark units.