Patent ID: 6341006
Filing Date: 2002-01-22
Classification: G03F,Y10S

Abstract:
A projection exposure apparatus comprising:an illumination optical system which applies light of a specific wavelength to a mask formed with a pattern; a projection optical system which projects a pattern image of said illuminated mask onto a substrate; hermetically sealing device which shuts off from an atmosphere an optical path extending from a light source of said illumination optical system to an end of said projection optical system which is closer to said mask; and at least one partition device which partitions a space in said hermetically sealing device to form a plurality of hermetic blocks which are to be filled with an inert gas, said at least one partition device being selectively movable between a first position where, when projection exposure is carried out, said partition device allows passage of exposure light and does not shut off said hermetic blocks from each other, and a second position where said partition device shuts off said hermetic blocks from each other when projection exposure is not carried out.