Lithographic apparatus and a device manufacturing method

Abstract

An immersion lithographic apparatus is provided having a substrate table including a drain configured to receive immersion fluid which leaks into a gap between an edge of a substrate on the substrate table and an edge of a recess in which the substrate is located. A thermal conditioning system is provided to thermally condition at least the portion of the recess supporting the substrate by directing one or more jets of fluid onto a reverse side of the section supporting the substrate.

The invention claimed is: 
     
       1. An A substrate table for an immersion lithographic apparatus, the immersion lithographic apparatus comprising: a projection system configured to project radiation onto a substrate, wherein the substrate table comprising comprises:
 a recess having a central support section configured to support a the substrate, the central support section having:
 a support surface having a protrusion to contact a bottom surface of the substrate, 
 a lateral surface at a non-zero angle non-parallel to the support surface, and 
 a bottom surface at a non-zero angle non-parallel to the lateral surface and facing away from the support surface, the lateral surface extending to the bottom surface of the central support section; and 
 
 a peripheral section of the substrate table that surrounds the central support section and defines the recess, the peripheral section being effectively thermally isolated from the central support section, and the peripheral section comprising:
 a drain opening arranged to face the recess and configured to receive an immersion fluid which leaks, in use, into a gap between an edge of the substrate when supported on the substrate table and an edge of the recess, the drain opening located above the bottom surface of the central support section and a cross-section across the face of the drain opening is arranged to be non-parallel to the support surface, and 
 a lateral surface facing, and spaced by an open qap gap from, the lateral surface of the central support section, wherein the lateral surface of the peripheral section is outward, in a horizontal direction, of an outer periphery of the bottom surface of the substrate when supported on the substrate table; and 
 
 a projection system configured to project radiation onto the substrate a heater and/or a channel configured to convey a heat transfer fluid. 
 
     
     
       2. The immersion lithographic apparatus substrate table of  claim 1 , further comprising a solid member spanning the open gap to directly connect the central support section and the peripheral section. 
     
     
       3. The immersion lithographic apparatus substrate table of  claim 2 , wherein the open gap extends below the member. 
     
     
       4. The immersion lithographic apparatus substrate table of  claim 2 , wherein the member is a separate body from the central support section and the peripheral section. 
     
     
       5. The immersion lithographic apparatus substrate table of  claim 2 , wherein the member is configured to reduce transfer of vibrations between the peripheral section and the central support section. 
     
     
       6. The immersion lithographic apparatus substrate table of  claim 1 , wherein a continuous open gap, including the gap and the open gap, separates the central support section and the peripheral sections section from the top of the central support section and peripheral section to the bottom of the central support section and peripheral section. 
     
     
       7. The immersion lithographic apparatus substrate table of  claim 1 , wherein the drain opening is located in a side surface of the peripheral section, the side surface at a non-zero angle non-parallel to the support surface. 
     
     
       8. The immersion lithographic apparatus substrate table of  claim 1 , wherein the peripheral section comprises a heater arranged to heat directly the peripheral section. 
     
     
       9. An A substrate table for an immersion lithographic apparatus, the immersion lithographic apparatus comprising: a projection system configured to project radiation onto a substrate, wherein the substrate table comprising comprises:
 a recess having a central support section configured to support a the substrate, the central support section having a support surface having a protrusion to contact a bottom surface of the substrate and having a lateral surface at a non-zero angle non-parallel to the support surface, and 
 a peripheral section of the substrate table that surrounds the central support section and defines the recess, the peripheral section being effectively thermally isolated from the central support section and the substrate when supported on the central support section, and the peripheral section comprising a drain opening arranged to face the recess and configured to receive an immersion fluid which leaks, in use, into a gap between an edge of the substrate when supported on the substrate table and an edge of the recess, wherein a cross-section across the face of the drain opening is arranged to be non-parallel to the support surface and wherein at least part of the lateral surface of the central support section is spaced by an open gap from at least part of a lateral surface of the peripheral section, the lateral surface of the peripheral section is outward, in a horizontal direction, of an outer periphery of the bottom surface of the substrate when supported on the substrate table, and 
 a solid member spanning the open gap to directly connect the central support section and the peripheral section; and a projection system configured to project radiation onto the substrate. 
 
     
     
       10. The immersion lithographic apparatus substrate table of  claim 9 , wherein the open gap extends below the member. 
     
     
       11. The immersion lithographic apparatus substrate table of  claim 9 , wherein the member is a separate body from the central support section and the peripheral section. 
     
     
       12. The immersion lithographic apparatus substrate table of  claim 9 , wherein the member is configured to reduce transfer of vibrations between the peripheral section and the central support section. 
     
     
       13. The immersion lithographic apparatus substrate table of  claim 9 , wherein the drain opening is located in a side surface of the peripheral section, the side surface at a non-zero angle non-parallel to the support surface. 
     
     
       14. The immersion lithographic apparatus substrate table of  claim 9 , wherein the peripheral section comprises a heater arranged to heat directly the peripheral section. 
     
     
       15. A device manufacturing method comprising:
 providing a substrate to a recess in a substrate table, the recess having a central support section supporting the substrate, the central support section having:
 a support surface having a protrusion that contacts a bottom surface of the substrate, 
 a lateral surface at a non-zero angle non-parallel to the support surface, and 
 a bottom surface at a non-zero angle non-parallel to the lateral surface and facing away from the support surface, the lateral surface extending to the bottom surface of the central support section; 
 
 providing immersion fluid to an upper surface of the substrate and/or the substrate table; 
 draining the immersion fluid that leaks into a gap between an edge of the substrate supported on the substrate table and an edge of the recess through a drain opening located in a peripheral section of the substrate table, the drain opening facing the recess and located above the bottom surface of the central support section and a cross-section across the face of the drain opening is non-parallel to the support surface, the peripheral section surrounding the central support section and defining the recess, and the peripheral section being effectively thermally isolated from the central support section and the substrate supported on the central support section, wherein a lateral surface of the peripheral section faces, and is spaced by an open gap from, the lateral surface of the central support section, the lateral surface of the peripheral section being outward, in a horizontal direction, of an outer periphery of the bottom surface of the substrate; and 
 providing thermal transfer in the substrate table using a heater and/or a channel configured to convey a heat transfer fluid; and 
 projecting radiation onto the substrate. 
 
     
     
       16. The method of  claim 15 , wherein the peripheral section is effectively mechanically isolated from the central support section. 
     
     
       17. The method of  claim 15 , wherein a solid member spans the open gap to directly connect the central support section and the peripheral section. 
     
     
       18. The method of  claim 17 , wherein the open gap extends below the member. 
     
     
       19. The method of  claim 17 , wherein the member is configured to reduce transfer of vibrations between the peripheral section and the central support section. 
     
     
       20. The immersion lithographic apparatus substrate table of  claim 1 , wherein the peripheral section is effectively mechanically isolated from the central support section. 
     
     
       21. The immersion lithographic apparatus substrate table of  claim 9 , wherein the open gap extends around the central support section, wherein an uppermost surface of the peripheral section adjacent the substrate when supported on the substrate table is generally coplanar with an upper surface of the substrate when supported on the substrate table, and wherein the drain opening is located above the member. 
     
     
       22. A lithographic apparatus comprising:
 the substrate table of claim 1; and   a projection system configured to project a pattern from a patterning device onto a substrate using a projection beam; and   a liquid supply system configured to supply a liquid to a space between the projection system and the substrate table.   
     
     
       23. A lithographic apparatus comprising:
 the substrate table of claim 9; and   a projection system configured to project a pattern from a patterning device onto a substrate using a projection beam; and   a liquid supply system configured to supply a liquid to a space between the projection system and the substrate table.