Patent ID: 8493545

Claim:
A method used in an immersion lithography apparatus in which an immersion liquid is supplied to a gap between an optical element of a projection optics and a workpiece during an immersion lithography process, the method comprising: supplying, during the immersion lithography process, the immersion liquid to the gap through a first channel without passing through a second channel; and supplying, during a cleanup process, a cleaning liquid onto a surface of an object, which is different from the workpiece, provided directly vertically below the optical element, a liquid supply port and a liquid recovery port, the cleaning liquid being supplied from above the object from the liquid supply port by delivering flow from the second channel such that only a portion of the surface of the object is covered by the cleaning liquid and at least a part of a remainder of the surface of the object is not covered by the cleaning liquid nor the immersion liquid, wherein the workpiece is moved directly vertically below and relative to the optical element, the liquid supply port and the liquid recovery port during the immersion lithography process, and wherein during the immersion lithography process, the immersion liquid is locally disposed on an upper surface of the workpiece, at least a part of a remainder of the upper surface of the workpiece not being covered by the immersion liquid nor the cleaning liquid.