Source: https://patents.google.com/patent/US9285683B2/en
Timestamp: 2019-07-19 17:16:04
Document Index: 166926803

Matched Legal Cases: ['Application No. 60', 'Application No. 60', 'Application No. 60', 'art 32', 'art 30', 'Application No. 05741209', 'Application No. 2012', 'Application No. 2006']

US9285683B2 - Apparatus and method for providing fluid for immersion lithography - Google Patents
US9285683B2
US9285683B2 US13/137,964 US201113137964A US9285683B2 US 9285683 B2 US9285683 B2 US 9285683B2 US 201113137964 A US201113137964 A US 201113137964A US 9285683 B2 US9285683 B2 US 9285683B2
US13/137,964
US20120013861A1 (en
2011-09-22 Priority to US13/137,964 priority patent/US9285683B2/en
2011-09-22 Application filed by Nikon Corp filed Critical Nikon Corp
2012-01-19 Publication of US20120013861A1 publication Critical patent/US20120013861A1/en
2016-03-15 Publication of US9285683B2 publication Critical patent/US9285683B2/en
An apparatus and method provide fluid for immersion lithography. A nozzle member that can move in a direction, is arranged to encircle a space under the optical element. The nozzle member can have an input to supply the immersion liquid to the space under the optical element during the exposure, and an output to remove the immersion liquid from a gap between the nozzle member and the wafer during the exposure. Immersion liquid can be supplied at a first rate to the space from a first portion of the nozzle member and at a second rate to the space from a second portion during the exposure. A wafer substrate is exposed by light through the immersion liquid.
This is a divisional of U.S. patent application Ser. No. 11/579,442 filed Nov. 2, 2006 (now U.S. Pat. No. 8,054,448), which is a National Phase of International Application No. PCT/US2005/014200 filed Apr. 27, 2005, which claims the benefit of U.S. Provisional Patent Application No. 60/568,345 filed May 4, 2004, U.S. Provisional Patent Application No. 60/623,170 filed Oct. 29, 2004 and U.S. Provisional Patent Application No. 60/623,172 filed Oct. 29, 2004. Said International Application No. PCT/US2005/014200 also is a Continuation-in-Part of International Application No. PCT/US2004/022915 filed Jul. 16, 2004. All of said above-identified applications are hereby incorporated herein by reference in their entireties.
This invention relates generally to immersion lithography and, more particularly, to apparatus and methods for providing fluid for immersion lithography. Specifically, this invention relates to improving fluid flow during immersion lithography.
Immersion lithography is a technique which can enhance the resolution of projection lithography by permitting exposures with numerical aperture (NA) greater than one, which is the theoretical maximum for conventional “dry” systems. By filling the space between the final optical element and the resist-coated target (i.e., wafer) with immersion liquid, immersion lithography permits exposure with light that would otherwise be totally internally reflected at an optic-air interface. Numerical apertures as high as the index of the immersion liquid (or of the resist or lens material, whichever is least) are possible. Liquid immersion also increases the wafer depth of focus, i.e., the tolerable error in the vertical position of the wafer, by the index of the immersion liquid compared to a dry system with the same numerical aperture.
FIG. 1 is a simplified elevational view schematically illustrating an immersion lithography system according to certain embodiments;
FIG. 2 is a perspective view of a nozzle for fluid delivery and recovery for immersion lithography according to certain embodiments;
FIG. 3 is a simplified cross-sectional view of the nozzle of FIG. 2 according to certain embodiments;
FIG. 4 is a cross-sectional view of the inner part of the nozzle of FIG. 2 according to certain embodiments;
FIG. 5 is a simplified cross-sectional view of the nozzle according to certain embodiments;
FIG. 9 is a simplified view schematically illustrating a pressure control system for fluid recovery in an immersion lithography system with immersion fluid stagnation prevention according to certain embodiments;
FIG. 10 is a perspective view of a nozzle for fluid delivery and recovery for immersion lithography where immersion fluid is injected on a non-scanning axis according to certain embodiments;
FIG. 11 is a perspective view of a nozzle for fluid delivery and recovery for immersion lithography where immersion fluid is input from a left side faster than immersion fluid is input from a right side according to certain embodiments;
FIG. 12 is a perspective view of a nozzle for fluid delivery and recovery for immersion lithography including a porous member according to certain embodiments; and
FIG. 13 is a perspective view of a nozzle for fluid delivery and recovery for immersion lithography including one or more porous members according to certain embodiments.
The inner part 32 has two groups or rows of holes 38 for supplying or recovering the fluid. Each row can be independently controlled to either supply or recover the fluid. In the case where both rows are chosen for fluid supply, all the fluid is recovered through the porous member 51 in the outer part 30. Since both rows are supplying fluid, a pressure can build up in the inner cavity causing deformation of the final optical element 22 of the projection lens 14 or the wafer 16 or both. The fluid flow across the final optical element 22 may also be limited, and thus the temperature of the fluid between the final optical element 22 and the wafer 16 may eventually rise, causing adverse effects. On the other hand, if one row is chosen for supply and the other for recovery, a fluid flow will be driven across the final optical element 22, minimizing temperature rise. It can also reduce the pressure otherwise created by supplying fluid from both rows. In this case, less fluid needs to be recovered through the porous member 51, lowering the fluid recovery requirement in the porous member. In other nozzle configurations, multiple fluid supplies and recoveries may be provided so as to optimize the performance.
FIGS. 10 and 11 are exemplary perspective views of a nozzle 20 for fluid delivery and recovery for immersion lithography where immersion fluid is injected on a non-scanning axis and immersion fluid is input from a left side faster than from a right side, respectively. Referring to FIG. 10, nozzle 20 includes an immersion fluid input 70 that provides immersion fluid in a non-scanning axis direction. The scanning axis is the axis in which the nozzle 20 can move to perform the immersion lithography. The nozzle 20 can move in a positive (e.g., upward) or negative (e.g., downward) direction along the scanning axis. The immersion fluid inputs 70 are located laterally on opposite sides of the projection lens 22 and can run substantially parallel to the scanning axis direction. Each immersion fluid input 70 includes one or more apertures or openings that allow immersion fluid to flow in and out of the inner cavity of the nozzle 20 under the projection lens 22.
As the nozzle 20 moves in either the positive or negative scanning axis directions, immersion fluid input 70 injects immersion fluid into the inner cavity in a non-scanning direction. In this example, the non-scanning axis direction can be substantially perpendicular or orthogonal to the scanning axis direction. In this manner, the immersion fluid flow under the projection lens 22 can be more consistent and uniform as the nozzle 20 moves in the positive or negative directions. The immersion lithography process can thus be improved by the even flow of immersion fluid under the projection lens 22.
In certain embodiments, as illustrated in FIG. 12, nozzle 20 can comprise a porous member 52. In certain embodiments, porous member 52 may be a mesh or may be formed of a porous material having holes typically in the size range of about 50-200 microns. For example, in certain embodiments, porous member 52 can be a wire mesh including woven pieces or layers of material made of metal, plastic, or the like, a porous metal, a porous glass, a porous plastic, a porous ceramic, or a sheet of material having chemically etched holes (e.g., by photo-etching) In certain embodiments, porous member 52 can be disposed at or near flat portion 33.
Additionally, the above examples can be applied to Twin-Stage-Type Lithography Systems. One Twin-Stage-Type Lithography System, for example, is disclosed in U.S. Pat. Nos. 6,262,796 and 6,341,007, the entire disclosures of which are incorporated herein by reference.
Thus, apparatus and methods for providing fluid for immersion lithography have been described. Furthermore, the above description are intended to be illustrative and not restrictive. Many other examples will be apparent upon reviewing the above examples. The scope of the invention should, therefore, be determined not with reference to the above examples.
exposing a wafer with exposure light from an optical element through an immersion liquid, while relatively moving the wafer and a nozzle member that is arranged to encircle a space under the optical element, in a scanning axis direction;
supplying, during the exposure in which the wafer and the nozzle member relatively move in the scanning axis direction, the immersion liquid at a first rate through a first portion of the nozzle member; and
supplying the immersion liquid at a second rate, that is different from the first rate, through a second portion of the nozzle member while the immersion liquid is being supplied at the first rate through the first portion of the nozzle member during the exposure in which the wafer and the nozzle member relatively move in the scanning axis direction,
wherein the immersion liquid supplied at the second rate is supplied in a second direction that is different from a first direction in which the immersion liquid is supplied at the first rate, and the first direction is substantially perpendicular to the scanning axis direction.
2. The method according to claim 1, wherein the first and second portions of the nozzle member are located on opposite sides of an opening in the nozzle member through which the exposure light is projected by the optical element.
3. The method according to claim 1, wherein the second direction is opposite to the first direction.
4. The method according to claim 1, wherein the first direction is toward an optical axis of the optical element.
5. The method according to claim 1, wherein the immersion liquid supplied at the first rate passes through a porous member into the space, the porous member including a plurality of holes.
6. The method according to claim 1, wherein the immersion liquid supplied at the second rate passes through a porous member into the space, the porous member including a plurality of holes.
7. The method according to claim 1, wherein the first and second directions cross the scanning axis direction in which the wafer and the nozzle member relatively move.
8. The method according to claim 1, wherein the first direction is toward an optical axis of the optical element, and the second direction is toward the optical axis of the optical element.
an optical element from which exposure light is supplied to a wafer to expose the wafer through an immersion liquid; and
a nozzle member arranged to encircle a space under the optical element, the immersion liquid being supplied to the space at a first rate through a first portion of the nozzle member and to the space at a second rate, that is different from the first rate, through a second portion of the nozzle member during an exposure operation in which the wafer and the nozzle member are relatively moved in a scanning axis direction while the immersion liquid is being supplied at the first rate through the first portion of the nozzle member and at the second rate through the second portion of the nozzle member,
10. The apparatus according to claim 9, wherein the first and second portions of the nozzle member are located on opposite sides of an opening in the nozzle member through which the exposure light is projected by the optical element.
11. The apparatus according to claim 9, wherein the second direction is opposite to the first direction.
12. The apparatus according to claim 9, wherein the first direction is toward an optical axis of the optical element.
13. The apparatus according to claim 9, wherein the first portion supplies the immersion liquid at the first rate through a porous member into the space, the porous member including a plurality of holes.
14. The apparatus according to claim 9, wherein the second portion supplies the immersion liquid at the second rate through a porous member into the space, the porous member including a plurality of holes.
15. The apparatus according to claim 9, wherein the first and second directions cross the scanning axis direction in which the wafer and the nozzle member relatively move.
16. The apparatus according to claim 9, wherein the first direction is toward an optical axis of the optical element, and the second direction is toward the optical axis of the optical element.
US13/137,964 2003-09-03 2011-09-22 Apparatus and method for providing fluid for immersion lithography Active 2027-02-27 US9285683B2 (en)
US11/579,442 Division US8054448B2 (en) 2003-09-03 2005-04-27 Apparatus and method for providing fluid for immersion lithography
PCT/US2005/014200 Division WO2005111722A2 (en) 2003-09-03 2005-04-27 Apparatus and method for providing fluid for immersion lithography
US10/579,442 Division US7721786B2 (en) 2004-06-30 2005-06-27 Casting nozzle
US20120013861A1 US20120013861A1 (en) 2012-01-19
US9285683B2 true US9285683B2 (en) 2016-03-15
Aug. 15, 2005 International Search Report in International Application No. PCT/USO4/22915.
Aug. 27, 2010 Office Action in U.S. Appl. No. 12/461,243.
Jan. 22, 2008 Office Action in corresponding European Application No. 05741209.0.
Jul. 9, 2013 Office Action issued in Japanese Patent Application No. 2012-015910 (with translation).
Mar. 3, 2009 Office Action in Japanese Application No. 2006-525323, with translation.
May 12, 2011 Office Action in U.S. Appl. No. 12/461,243.
US20070222967A1 (en) 2007-09-27