Patent ID: 6972836
Filing Date: 2005-12-06
Classification: G01J,G03F

Abstract:
1. A measuring method of an illuminance unevenness of an exposure apparatus in which the illuminance unevenness generated in a finite area on a photosensitive substrate is measured with respect to the exposure apparatus to irradiate a photomask with an illumination light emitted from an illuminating optical system, to project the light passed through the photomask onto the finite area on the photosensitive substrate via the projection optical system and to expose the photomask to the light, said method comprising: measuring a transmittance of said projection optical system of the light emitted from one point, which is optically conjugate with an imaging point, on said photomask, traveling inside said projection optical system and reaching said imaging point for each of a plurality of imaging points in the finite area on said photosensitive substrate; calculating an average value of the transmittance of the light emitted from said one point, traveling inside said projection optical system and converging on said imaging point about a plurality of paths inside said projection optical system for each of a plurality of imaging points in the finite area on said photosensitive substrate; and calculating the illuminance unevenness in the finite area on said photosensitive substrate from a distribution of said average values of the transmittance obtained for said each imaging point.