Projection type exposing apparatus

Abstract

Alignment of a mask with a projection-type exposing apparatus and alignment of the mask with a substrate are provided. Plural exposure areas of the substrate are exposed by light of a predetermined wavelength, which is also used for alignment purposes to reduce alignment error due to aberration of a projection optical system. A first alignment mark is disposed in a first area between adjacent exposure areas of the substrate. The mask has a main area, a second area in which a second mark is disposed, and a third area in which a third mark is disposed, the second area being outside of the main area and the third area being inside the second area. An illuminating device has a first status in which the second and third areas are illuminated simultaneously and has a second status in which the third area is illuminated, a first area adjacent to one of the exposure areas also being illuminated when the illuminating device has the second status. In the first status, a first detector detects the position of an image of the second mark formed by an objective optical system. In the second status, a second detector detects displacement between images of the first and third marks formed by the objective optical system and produces a detection signal. The mask is displaced relative to the substrate in response to the detection signal, so that the images of the first and third marks assume a predetermined relationship.