Patent ID: 8018573

Claim:
A lithographic apparatus, comprising: a substrate table constructed to hold a substrate; a projection system configured to project a radiation beam onto a target portion of the substrate; a liquid confinement structure configured to at least partially confine a liquid between the projection system and the substrate table, and a liquid supply system configured to supply liquid to the liquid confinement structure and comprising a pressure regulating device configured and arranged in the liquid supply system to reduce a pressure fluctuation in liquid being supplied to the liquid confinement structure, wherein the pressure regulating device is not the source of pressure in the liquid supply system, and wherein the pressure regulating device is one or more selected from the following: a valve configured to change the flow rate of the liquid in the liquid supply system from 0 to about 2 or more liters/minute in 1 to 5 seconds; a drain and a valve in the liquid supply system where the valve is configured to switch the flow of the liquid between the direction to the liquid confinement structure and the direction to the drain; a bleed flow device for use with a valve in the liquid supply system where the bleed flow device is configured to create a bleed flow of liquid in the liquid supply system even when the valve is switched to an off position; and a buffer volume of liquid separated from the liquid supply system by a flexible membrane, the buffer volume configured to release liquid from the buffer volume when the volume of liquid in the liquid supply system drops below a threshold and configured to receive liquid into the buffer volume when the volume of liquid in the liquid supply system rises above a threshold.