Abstract: A projection exposure apparatus according to the present invention comprises a projection optical system for projecting a pattern of a mask onto each of exposure areas on a photosensitive substrate, and a mark detection system of off-axis type spaced apart from the projection optical system by a predetermined distance. According to one aspect of the present invention, the projection exposure apparatus includes a calculating means for determining an offset amount of an imaging position of the projection optical system and an offset amount of a best focus position of the mark detection system of off-axis type on the basis of the amount of change of an environmental condition to which the projection optical system and the mark detection system are subjected. The detection of a positioning mark on the substrate is performed after a surface of the substrate at a position of the mark detection system is aligned with the best focus position, in consideration of the offset amounts.

Abstract: Plural shot areas arranged in succession in a two-dimensional array on a substrate are aligned to a predetermined reference position in a fixed coordinate system. At least three of the plural shot areas are selected as specified shot areas. Coordinate values (positions) of alignment marks associated, respectively, with the specified shot areas are measured. Anticipated coordinate values are calculated from preset coordinate values, based on an array model of the shot areas, predetermined by a first equation. A unique relation defined by a second equation is assumed, between the anticipated coordinate values and actual coordinate values in the alignment. Parameters of the relation are determined so as to minimize the average error between the measured coordinate values and coordinate values calculated from the relation. Actual coordinate values of the shot areas on the substrate are calculated based on the parameters and the anticipated coordinate values.