Lithographic apparatus and device manufacturing method

Abstract

A liquid confinement structure configured to contain a liquid in a space between a projection system and a substrate has a recess in its lower surface which is open to both a relatively low pressure source and a relatively high pressure source and through which liquid and/or gas from between the liquid confinement structure and the substrate is extracted.

1 .- 24 . (canceled) 
   
   
       25 . A lithographic projection apparatus arranged to project a pattern from a patterning device onto a substrate using a projection system, the lithographic apparatus comprising:
 a liquid supply system arranged to supply immersion liquid to a space between the projection system and a substrate table configured to hold the substrate, the liquid supply system comprising a liquid confinement structure to substantially contain the liquid in the space, the liquid confinement structure comprising, in a surface facing toward the substrate table, a recess having therein a first port open to a first pressure source and a second port open to a second pressure source, the first pressure source being at a lower pressure than the second pressure source such that there is a flow of fluid toward the first pressure source from the second pressure source; and   a liquid removal device positioned radially inwardly, relative to the exposure area of the projection system, of the recess.   
   
   
       26 . The apparatus of  claim 25 , wherein the liquid removal device is arranged to remove substantially only liquid. 
   
   
       27 . The apparatus of  claim 26 , wherein the liquid removal device comprises a porous plate. 
   
   
       28 . The apparatus of  claim 25 , wherein the first port and the second port are positioned in the recess opposite the opening of the recess in the surface. 
   
   
       29 . The apparatus of  claim 25 , wherein the first port is positioned radially outwardly, relative to the exposure area of the projection system, of the second port. 
   
   
       30 . The apparatus of  claim 25 , wherein the liquid confinement structure surrounds the space. 
   
   
       31 . A device manufacturing method, comprising:
 containing a liquid in a space between a projection system and a substrate by removing liquid and/or gas from between a liquid confinement structure and a surface of the substrate through a recess in a surface of the liquid confinement structure facing the substrate, the recess having a respective port to first and second pressure sources, the first pressure source being at a lower pressure than the second pressure source such that there is a flow of fluid toward the first pressure source from the second pressure source;   removing liquid at a position radially inwardly, relative to the exposure area of the projection system, of the recess; and   projecting a patterned beam of radiation through the liquid onto the substrate using the projection system.   
   
   
       32 . The method of  claim 31 , comprising removing substantially only liquid at the position radially inwardly of the recess. 
   
   
       33 . A lithographic projection apparatus arranged to project a pattern from a patterning device onto a substrate using a projection system, the lithographic apparatus comprising:
 a liquid supply system arranged to supply immersion liquid to a space between the projection system and a substrate table configured to hold the substrate, the liquid supply system comprising a liquid confinement structure to substantially contain the liquid in the space, the liquid confinement structure comprising, in a surface facing toward the substrate table, a recess having therein a first port open to a first pressure source and a second port open to a second pressure source, the first pressure source being at a lower pressure than the second pressure source such that there is a flow of fluid toward the first pressure source from the second pressure source and the first port, or the second port, or both the first and second ports, comprising a plurality of discrete holes.   
   
   
       34 . The apparatus of  claim 33 , wherein the first port is positioned radially outwardly, relative to the exposure area of the projection system, of the second port. 
   
   
       35 . The apparatus of  claim 33 , wherein a gas jet is positioned radially outwardly, relative to the exposure area of the projection system, of the recess. 
   
   
       36 . The apparatus of  claim 35 , wherein the gas jet creates a flow of gas between the liquid confinement structure and the substrate radially inwardly, relative to the exposure area of the projection system, into the recess. 
   
   
       37 . The apparatus of  claim 35 , wherein the gas jet supplies humidified gas. 
   
   
       38 . The apparatus of  claim 33 , wherein the first port and the second port are positioned in the recess opposite the opening of the recess in the surface. 
   
   
       39 . The apparatus of  claim 33 , further comprising a liquid removal device positioned radially inwardly, relative to the exposure area of the projection system, of the recess. 
   
   
       40 . The apparatus of  claim 39 , wherein the liquid removal device is arranged to remove substantially only liquid. 
   
   
       41 . The apparatus of  claim 33 , wherein the second pressure source is ambient atmosphere. 
   
   
       42 . The apparatus of  claim 33 , wherein the first port and the second port are arranged at different radial distances in the lower surface and arranged at a distance further away from the substrate table than the recess opening. 
   
   
       43 . A device manufacturing method, comprising:
 containing a liquid in a space between a projection system and a substrate by removing liquid and/or gas from between a liquid confinement structure and a surface of the substrate through a recess in a surface of the liquid confinement structure facing the substrate, the recess having a respective port to first and second pressure sources, the first pressure source being at a lower pressure than the second pressure source such that there is a flow of fluid toward the first pressure source from the second pressure source and the first port, or the second port, or both the first and second ports, comprising a plurality of discrete holes; and   projecting a patterned beam of radiation through the liquid onto the substrate using the projection system.   
   
   
       44 . The method of  claim 43 , further comprising removing liquid at a position radially inwardly, relative to the exposure area of the projection system, of the recess.