Lithographic apparatus, fluid handling structure for use in a lithographic apparatus and device manufacturing method

Abstract

A lithographic apparatus including a fluid handling structure configured to contain immersion fluid in a space adjacent to an upper surface of the substrate table and/or a substrate located in a recess of the substrate table, a cover having a planar main body that, in use, extends around a substrate from the upper surface to a peripheral section of an upper major face of the substrate in order to cover a gap between an edge of the recess and an edge of the substrate, and an immersion fluid film disruptor, configured to disrupt the formation of a film of immersion fluid between an edge of the cover and immersion fluid contained by the fluid handling structure during movement of the substrate table relative to the fluid handling structure.

The invention claimed is: 
     
       1. A lithographic apparatus comprising:
 a substrate table having an upper surface and a recess in the upper surface that is configured to receive and support a substrate; 
 a fluid handling structure configured to contain immersion fluid in a space adjacent to the upper surface of the substrate table and/or a substrate located in the recess; 
 a cover comprising a planar main body that, in use, extends around a substrate from the upper surface to a peripheral section of an upper major face of the substrate in order to cover a gap between an edge of the recess and an edge of the substrate; 
 an immersion fluid film disruptor, configured to disrupt the formation of a film of immersion fluid between an edge of the cover substrate and immersion fluid contained by the fluid handling structure during movement of the substrate table relative to the fluid handling structure, the immersion fluid film disruptor comprising a structure in or on a surface of the fluid handling structure opposite the upper major surface of the substrate and/or the upper surface of the substrate table, to form a plurality of discrete gas jets; and 
 a controller control system, configured to control supply of gas to the structure of the immersion fluid film disruptor such that the jets of gas are provided when at least part of the structure of the immersion fluid film disruptor is in the region of the cover edge of the substrate and the lets jets of gas are not provided when the at least part of the structure of the immersion fluid film disruptor is not in the region of the cover edge of the substrate. 
 
     
     
       2. The lithographic apparatus according to  claim 1 , wherein the structure of the immersion fluid film disruptor comprises a plurality of apertures, formed in the surface of the fluid handling structure, to provide the gas jets. 
     
     
       3. The lithographic apparatus according to  claim 2 , wherein the apertures are each configured to provide a jet of gas onto the film of immersion liquid as it forms. 
     
     
       4. The lithographic apparatus according to  claim 2 , wherein the surface of the fluid handling structure comprises a line of openings, surrounding the space in which immersion fluid is contained, configured to extract immersion fluid in order to contain the immersion fluid in the space; and the plurality of gas jets are provided outwardly of the line of openings. 
     
     
       5. The lithographic apparatus according to  claim 4 , wherein the plurality of apertures providing the gas jets are arranged along a second line, parallel to the line of openings. 
     
     
       6. The lithographic apparatus according to  claim 2 , wherein the controller control system is configured such that it can control the supply of gas to a first group of one or more apertures independently from a second group of one or more apertures. 
     
     
       7. The lithographic apparatus according to  claim 2 , wherein the control system is configured to control the supply the gas is supplied to the apertures such that the maximum velocity of the gas is in the range of from approximately Ma 0.3 to Ma 0.6. 
     
     
       8. The lithographic apparatus according to  claim 2 , wherein the separation between the center of one aperture of the plurality of apertures and the center of an adjacent aperture of the plurality of apertures is in the range of from approximately 100 μm to 1 mm. 
     
     
       9. The lithographic apparatus according to  claim 2 , wherein the width of the apertures is in the range of from approximately 50 μm to 150 μm. 
     
     
       10. The lithographic apparatus according to  claim 2 , wherein the fluid handling structure comprises a plurality of openings, each provided between two adjacent apertures, wherein the openings are connected to an underpressure source. 
     
     
       11. A fluid handling structure for a lithographic apparatus that includes a substrate table having a substantially planar upper surface in which is formed a recess that is configured to receive and support a substrate and a cover comprising a substantially planar main body that, in use, extends around the substrate from the upper surface to a peripheral section of an upper major face of the substrate in order to cover a gap between an edge of the recess and an edge of the substrate, the fluid handling structure comprising a plurality of apertures configured to provide a corresponding plurality of discrete gas jets to disrupt the formation of a film of immersion fluid between an edge of the cover substrate and immersion fluid contained by the fluid handling structure during movement of the substrate table relative to the fluid handling structure, and a controller control system configured to control supply of gas to the apertures such that the jets of gas are provided when the apertures are in the region of the cover edge of the substrate and the jets of gas are not provided when the apertures are not in the region of the cover edge of the substrate. 
     
     
       12. The fluid handling structure according to  claim 11 , wherein the plurality of gas jets are provided by a corresponding plurality of apertures formed in a surface of the fluid handling structure opposite the an upper major surface of the substrate and/or the upper surface of the substrate table. 
     
     
       13. The fluid handling structure according to  claim 12 , wherein the surface of the fluid handling structure comprises a line of openings, surrounding the space in which immersion fluid is contained, configured to extract immersion fluid in order to contain the immersion fluid in the space; and the plurality of gas jets are provided outwardly of the line of openings. 
     
     
       14. The fluid handling structure according to  claim 11 , wherein further comprising a control system configured to control supply of the gas is supplied to the apertures such that the maximum velocity of the gas is in the range of from approximately Ma 0.3 to Ma 0.6. 
     
     
       15. The fluid handling structure according to  claim 11 , wherein the separation between the center of one aperture of the plurality of apertures and the center of an adjacent aperture of the plurality of apertures is in the range of from approximately 100 μm to 1 mm. 
     
     
       16. The fluid handling structure according to  claim 11 , wherein the width of the apertures is in the range of from approximately 50 μm to 150 μm. 
     
     
       17. The fluid handling structure according to  claim 11 , wherein the fluid handling structure comprises a plurality of openings, each provided between two adjacent apertures, wherein the openings are connected to an underpressure source. 
     
     
       18. A device manufacturing method, comprising:
 providing a substrate to a substrate table having an upper surface and a recess in the upper surface that is configured to receive and support the substrate; 
 providing a cover comprising a planar main body such that it extends around the substrate from the upper surface to a peripheral section of an upper major face of the substrate in order to cover a gap between an edge of the recess and an edge of the substrate; 
 providing an immersion fluid to a space between a final element of a projection system and the substrate and/or a substrate table using a fluid handling structure; 
 providing a plurality of discrete gas jets from a structure in or on a surface of the fluid handling structure that is opposite the an upper major surface of the substrate and/or the upper surface of the substrate table in order to disrupt the formation of a film of immersion fluid between an edge of the cover substrate and immersion fluid contained by the fluid handling structure during movement of the substrate table relative to the fluid handling structure; and 
 controlling supply of gas to the gas lets jets such that the jets of gas are provided when at least part of the structure of the discrete gas jets is in the region of the cover edge of the substrate and the jets of gas are not provided when the at least part of the structure of the discrete gas jets is not in the region of the cover edge of the substrate. 
 
     
     
       19. The method of  claim 18 , wherein the plurality of gas jets are provided by a corresponding plurality of apertures formed in the surface of the fluid handling structure and the controlling comprises controlling supply of gas to a first group of one or more apertures independently from a second group of one or more apertures. 
     
     
       20. The method of  claim 18 , further comprising exhausting gas through a plurality of openings, each opening provided between two adjacent apertures providing a respective gas jet. 
     
     
       21. A liquid handling structure for a lithographic apparatus, the liquid handling structure configured to contain liquid in a space between a projection system of the lithographic apparatus and an upper major surface of a substrate table of the lithographic apparatus and/or of a substrate when located on the substrate table, the liquid handling structure comprising:
 an outlet configured to remove liquid from the space;   a plurality of openings located outward, relative to the space, of the outlet, the openings configured to provide respective flows of gas incident on the upper major surface that are spaced apart at the upper major surface;   a gas knife located outward, relative to the space, of the plurality of openings, the gas knife configured to provide a flow of gas incident on the upper major surface; and   a control system, configured to control supply of gas to the plurality of openings so as to provide the respective flows of gas from the plurality of openings when at least part of the plurality of openings is in the region of an edge of the substrate and to provide the respective flows of gas from the plurality of openings so as to divide liquid on the upper major surface while intentionally allowing liquid to pass between adjacent respective flows, and control supply of gas to the gas knife to provide the flow of gas from the gas knife to block liquid that passes between the adjacent respective flows from the plurality of openings.   
     
     
       22. The liquid handling structure according to claim 21, wherein the outlet comprises a line of apertures configured to surround the space in which liquid is contained, the apertures configured to extract liquid in order to contain liquid in the space. 
     
     
       23. The liquid handling structure according to claim 22, wherein the plurality of openings are arranged along a second line, substantially parallel to the line of apertures of the outlet. 
     
     
       24. The liquid handling structure according to claim 21, wherein the control system is further configured to control the supply of gas to a first group of the plurality of openings independently from a second group of the plurality of openings. 
     
     
       25. The liquid handling structure according to claim 21, wherein the control system is further configured to control the supply of gas to the plurality of openings such that the maximum velocity of the gas is in the range of from about Ma 0.3 to about Ma 0.6. 
     
     
       26. The liquid handling structure according to claim 21, wherein a separation between a center of one opening of the plurality of openings and a center of an adjacent opening of the plurality of openings is selected from the range of about 100 μm to about 1 mm. 
     
     
       27. The liquid handling structure according to claim 21, wherein a cross-sectional width of each of the plurality of openings is selected from the range of about 50 μm to about 150 μm. 
     
     
       28. The liquid handling structure according to claim 21, further comprising a plurality of apertures configured to exhaust gas, each aperture provided between two adjacent openings of the plurality of openings. 
     
     
       29. A lithographic apparatus comprising:
 the substrate table;   the projection system; and   the liquid handling structure of claim 21.   
     
     
       30. The lithographic apparatus according to claim 29, wherein the substrate table has a recess in the major upper surface of the substrate, the recess configured to receive and support the substrate. 
     
     
       31. The liquid handling structure according to claim 21, wherein a gap between an edge of one opening of the plurality of openings and an edge of an adjacent opening of the plurality of openings is at least 50 μm. 
     
     
       32. A device manufacturing method, comprising:
 providing a liquid to a space between a projection system of a lithographic apparatus and an upper major surface of a substrate table of the lithographic apparatus and/or of a substrate when located on the substrate table;   containing liquid in the space by removing liquid from the space using an outlet of a liquid handling structure of the lithographic apparatus;   providing a respective flow of gas incident on the upper major surface from each opening of a plurality of openings of the liquid handling structure, the openings located outward, relative to the space, of the outlet;   providing a flow of gas incident on the upper major surface from a gas knife of the liquid handling structure, the gas knife located outward, relative to the space, of the plurality of openings; and   controlling supply of gas to the plurality of openings so as to provide the respective flows of gas from the plurality of openings when at least part of the plurality of openings is in the region of an edge of the substrate and to provide the respective flows of gas from the plurality of openings so as to divide liquid on the upper major surface while intentionally allowing liquid to pass between adjacent respective flows, and controlling supply of gas to the gas knife such that the flow of gas therefrom blocks liquid that passes between the adjacent respective flows from the plurality of openings.   
     
     
       33. The method according to claim 32, wherein the outlet comprises a line of apertures surrounding the space in which liquid is contained, the apertures extracting liquid in order to contain liquid in the space. 
     
     
       34. The method according to claim 33, wherein the plurality of openings are arranged along a second line, substantially parallel to the line of apertures of the outlet. 
     
     
       35. The method according to claim 32, further comprising controlling the supply of gas to a first group of the plurality of openings independently from a second group of the plurality of openings. 
     
     
       36. The method according to claim 32, further comprising controlling the supply of gas to the plurality of openings such that the maximum velocity of the gas is in the range of from about Ma 0.3 to about Ma 0.6. 
     
     
       37. The method according to claim 32, wherein a separation between a center of one opening of the plurality of openings and a center of an adjacent opening of the plurality of openings is selected from the range of about 100 μm to about 1 mm. 
     
     
       38. The method according to claim 32, wherein a cross-sectional width of each of the plurality of openings is selected from the range of about 50 μm to about 150 μm. 
     
     
       39. The method according to claim 32, further comprising exhausting gas using a plurality of apertures, each aperture provided between two adjacent openings of the plurality of openings. 
     
     
       40. The method according to claim 32, wherein a gap between an edge of one opening of the plurality of openings and an edge of an adjacent opening of the plurality of openings is at least 50 μm.