EXPOSURE DEVICE AND DEVICE MANUFACTURING METHOD

PROBLEM TO BE SOLVED: To maintain a space including an optical path of illumination light radiated to a mask in a clean state without surrounding the entire mask stage device including a mask stage by an airtight shield container.SOLUTION: A first space 181 including an optical path of illumination light between an illumination unit IOP and a reticle R is subjected to a gas purge by a purge gas (CDA, for instance) supplied from a gas supply system. Also, the first space is structured to allow the movement of a reticle stage RST. Thus, the first space cannot be a completely sealed space and is communicated with the outside through a prescribed clearance, but since a second space 183 in an almost airtight state inside which the purge gas is supplied is present surrounding the clearance, intrusion of an impurity-containing gas from the outside to the first space is prevented without surrounding an entire reticle stage device 20 by an exclusive large-sized shield container.