Environmental system including vacuum scavenge for an immersion lithography apparatus

• US 20070132974A1
• Filed: 02/02/2007
• Published: 06/14/2007
• Est. Priority Date: 04/10/2003
• Status: Active Grant

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Sogard, Michael, Hazelton, Andrew
• Granted Patent: US 8,089,610 B2
• Time in Patent Office: Days
• US Class Current: 355/53
• CPC Class Codes: G03F 7/2041 in the presence of a fluid, e.g. immersion; using fluid cooling means
• CPC Class Codes: G03F 7/70341 Details of immersion lithography aspects, e.g. exposure media or control of immersion liquid supply chemical composition of immersion liquids G03F7/2041
• CPC Class Codes: G03F 7/70775 Position control, e.g. interferometers or encoders for determining the stage position
• CPC Class Codes: G03F 7/70816 Bearings
• CPC Class Codes: G03F 7/70866 of mask or workpiece
• CPC Class Codes: G03F 7/70875 Temperature, e.g. temperature control of masks or workpieces via control of stage temperature
• CPC Class Codes: G03F 7/709 Vibration, e.g. vibration detection, compensation, suppression or isolation

Abstract

A lithographic projection apparatus includes a liquid confinement structure extending along at least a part of a boundary of a space between a projection system and a substrate table, the space having a cross-sectional area smaller than the area of the substrate. The liquid confinement structure includes a first inlet to supply liquid, through which the patterned beam is projected, to the space, a first outlet to remove liquid after the liquid has passed under the projection system, a second inlet formed in a face of the structure, the face arranged to oppose a surface of the substrate, and located radially outward, with respect to an optical axis of the projection system, of the space to supply gas, and a second outlet formed in the face and located radially outward, with respect to an optical axis of the projection system, of the second inlet to remove gas.

Claims

1. A lithographic projection apparatus comprising:

a support structure configured to hold a patterning device and movable in a scanning direction, the patterning device configured to pattern a beam of radiation according to a desired pattern;

a substrate table configured to hold a substrate and movable in a scanning direction;

a projection system configured to project the patterned beam onto a target portion of the substrate; and

a liquid confinement structure extending along at least a part of a boundary of a space between the projection system and the substrate table, the space having a cross-sectional area smaller than the area of the substrate, the liquid confinement structure positioned adjacent a final surface of the projection system and comprising;

a first inlet to supply liquid, through which the patterned beam is to be projected, to the space,

a first outlet to remove liquid after the liquid has passed under the projection system,

a second inlet formed in a face of the structure, the face arranged to oppose a surface of the substrate, and located radially outward, with respect to an optical axis of the projection system, of the space to supply gas, and

a second outlet formed in the face and located radially outward, with respect to an optical axis of the projection system, of the second inlet to remove gas.

2. The apparatus according to claim 1, wherein the area has a periphery conforming to a shape of an image field of the projection system.

3. The apparatus according to claim 1, wherein the inlet is configured to supply the liquid at a first side of the projection system and the outlet is configured to remove the liquid at a second side of the projection system as the substrate is moved under the projection system in a direction from the first side to the second side.

4. The apparatus according to claim 1, wherein the second inlet, the second outlet, or both, extend around the final surface of the projection system.

5. The apparatus according to claim 1, wherein the second inlet, the second outlet, or both, comprise a groove in the face.

6. The apparatus according to claim 5, wherein the groove is circular and extends around the space.

7. The apparatus according to claim 1, wherein the structure forms a closed loop around the space.

8. A lithographic projection apparatus comprising:

a support structure configured to hold a patterning device, the patterning device configured to pattern a beam of radiation according to a desired pattern;

a substrate table configured to hold a substrate;

a projection system configured to project the patterned beam onto a target portion of the substrate; and

a liquid confinement structure extending along at least a part of a boundary of a space between the projection system and the substrate table, the space having a cross-sectional area smaller than the area of the substrate, the liquid confinement structure positioned adjacent a final surface of the projection system and comprising;

a first inlet configured to supply a liquid, through which the patterned beam is to be projected, to the space,

a second inlet configured to supply gas and formed in a face of the structure, the face arranged to oppose a surface of the substrate and the second inlet located radially outward, with respect to an optical axis of the projection system, of and substantially around the space, and

a second outlet configured to remove gas and formed in the face, the second outlet located radially outward, with respect to an optical axis of the projection system, of and substantially around the second inlet.

9. The apparatus according to claim 8, wherein the area has a periphery conforming to a shape of an image field of the projection system.

10. The apparatus according to claim 8, wherein the first inlet is configured to supply the liquid at a first side of the projection system and the apparatus further comprises a second outlet configured to remove the liquid at a second side of the projection system as the substrate is moved under the projection system in a direction from the first side to the second side.

11. The apparatus according to claim 8, wherein the second inlet, the second outlet, or both, comprise a groove in the face.

12. The apparatus according to claim 11, wherein the groove is circular.

13. The apparatus according to claim 8, wherein the support structure and the substrate table are movable in a scanning direction to expose the substrate.