Systems and methods for insitu lens cleaning using ozone in immersion lithography

摘要

An immersion lithography apparatus is provided that includes an energy source, a projection optical system, a stage, a showerhead including an immersion liquid supply device and an immersion liquid discharge device that produces a flow of liquid within an exposure zone, 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. In an embodiment, the cleaning device includes an ozone generation unit produces a flow of ozone into the exposure zone. In embodiments, the apparatus includes a stage that includes a dose sensor and/or an ultra-violet light source. A method for insitu cleaning of a final lens element within an immersion lithography system having an immersion fluid showerhead that provides immersion fluid to an exposure zone of the immersion lithography system is also provided.

主权项

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.