Patent ID: 7190455

Claim:
A method of detecting disposition of a plurality of shot areas on an object, the plurality of shot areas being exposed to a pattern in accordance with the detected disposition, said method comprising: a first detection step of detecting an alignment mark in the plurality of shot areas, the alignment mark including elements that have an interval therebetween; an evaluation step of evaluating reproducibility of the interval of the detected alignment mark; a determination step of determining a number of alignment marks in the plurality of shot areas based on the evaluated reproducibility; and a second detection step of using a detector to detect the disposition of the plurality of shot areas by detecting a plurality of alignment marks in the plurality of shot areas, a number of the plurality of alignment marks having been determined by said determination step, wherein said determination step determines, as the number of alignment marks, a minimum natural number Ns that satisfies Ns≧α·(Mr/Ar) 2 /Nm, where Mr is the reproducibility, Nm is a number of the mark elements included in the alignment mark, Ar is required alignment accuracy, and α is a corrective coefficient that is not smaller than 1 and not greater than 3.