Patent ID: 8817226
Filing Date: 2014-08-26
Classification: G03F

Abstract:
1. An immersion lithography apparatus, comprising: an energy source; a projection optical system; a stage that moves a substrate on which the substrate is placed; a showerhead including an immersion liquid supply device and an immersion liquid discharge device that produces a flow of an immersion liquid between the projection optical system and the substrate; and a cleaning device that cleans a portion of the projection optical system having been contacted with the immersion liquid by means of a cleaning gas and without irradiating UV radiation on the portion of the projection optical system during application of the cleaning gas, wherein the cleaning device includes a gas supply device on one side of the portion of the projection optical system and a gas discharge device on another side of the portion of the projection optical system such that the gas supply device produces a gas flow comprising ozone across the portion of the projection optical system from the one side to the other side.