FORMATION OF MASK PATTERN

PURPOSE:To improve quality control by adding dummy patterns to the pattern corresponding to parts which are defective devices, thereby deciding the parts transferred with these patterns always as defective as thes parts do not function as a circuit. CONSTITUTION:The mask pattern is so constituted that device patterns A can be transferred to the entire part of a wafer 5 with a shot 4 as one unit in the same manner as heretofore on a master mask 3. Such patterns B which do not function as circuit patterns, i.e., as devices when transferred, for example, the square patterns painted solid black, are, thereupon, superposed and arranged on the device patterns A having the parts protruding from the wafer 5, i.e. the parts where the outer peripheral part of the wafer 5 passes in the device patterns A and the so-called defect patterns are formed, namely, the defective parts. The arrangement and shapes of such dummy patterns are formed as the patterns, painted solid black, to a rectangular shape nearly analogous with the shape of the small patterns A of several hundred mum of one side.