EXPOSURE METHOD AND SYSTEM, AND DEVICE PRODUCING METHOD

摘要

An exposure method and system capable of providing stable imaging characteristics even when gas other than a purge gas remains on the light path of exposure light, or even when the residual concentration of gas other than the purge gas varies. Vacuum-UV-region exposure light (IL) from an exposure light source (1) illuminates a reticle (R) to transfer the reticle's pattern image onto a wafer (W) via a projection optical system (PL). The reticle (R) and the wafer (W) are respectively housed in a reticle stage room (40) and a wafer stage room (60) that are air-tight rooms, the inside of the projection optical system (PL) is turned to an air-tight room, and purge gas transmitting the exposure light (IL) is supplied to those air-tight rooms from a gas purifying device (71). For example, imaging characteristics of the projection optical system (PL) are adjusted via an imaging characteristic controller (57) according to the residual concentration of gas other than the purge gas in the projection optical system (PL) so as to offset variation amounts of imaging characteristics caused by this residual concentration.