US6555834B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas flushing system for use in lithographic apparatus
Assignee: ASML Netherlands BV
•
Filing: 2000-11-03
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Granted: 2003-04-29
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Expires: 2020-11-03
Abstract
Abstract In a lithographic apparatus using exposure radiation of a relatively short wavelength, e.g. 157 or 126 nm, a laminar flow of N 2 is provided across parts of the beam path in or adjacent to moving components of the apparatus. The laminar flow is faster than the maximum speed of the moving components and the diffusion rate of air thereby minimizing the contamination of the N 2 by mixing with air. Laminar flow may be ensured by providing partitions to divide the beam path into separate spaces, by covering rough or non-planar surfaces in components on or adjacent to the laminar flow and by providing aerodynamic members.
Inventors
- 👤 Erik R. Loopstra
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:09
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/708; G03F7/70908; G03F7/70933; H; H10; H10P; H10P76/00; G03F7/70691; G03F7/70716; G03F7/70858; G03F7/70866; G03F7/70983
Claims Analysis
Total Claims: 52
Claim 1
Independent Claim
114 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation, wherein said substantially laminar flow of flushing gas traverses a substantially non-obstructed region in said projection apparatus.
Claim 2
Dependent Claim
114 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation, wherein said substantially laminar flow of flushing gas traverses a substantially non-obstructed region in said projection apparatus.
Claim 3
Dependent Claim
36 words
Apparatus according to claim 1 wherein said gas supply comprises a supply of flushing gas, a gas flow regulator and an evacuator constructed and arranged to remove flushing gas from said part of said beam path.
Claim 4
Dependent Claim
13 words
Apparatus according to claim 2 wherein said flow regulator comprises a flow restrictor.
Claim 5
Dependent Claim
13 words
Apparatus according to claim 2 wherein said flow regulator comprises a blowing unit.
Claim 6
Dependent Claim
29 words
Apparatus according to claim 1 , wherein said at least a part of the path includes a plurality of parts of said beam path substantially separated from each other.
Claim 7
Dependent Claim
39 words
Apparatus according to claim 1 , wherein said gas supply is arranged to provide separate laminar gas flows across a plurality of parts of said beam path, said parts of said beam path being substantially isolated from each other.
Claim 8
Dependent Claim
38 words
Apparatus according to claim 5 further comprising at least one partition comprised of a material substantially transparent to said radiation and positioned parallel to the direction of said laminar flow to isolate said part of said beam path.
Claim 9
Dependent Claim
24 words
The apparatus according to claim 7 , wherein said partition closes a recess in said first object table in which said mask is mounted.
Claim 10
Dependent Claim
60 words
Apparatus according to claim 1 further comprising at least one cover member formed of a material substantially transparent to said radiation, said cover member being substantially planar and provided substantially parallel to the direction of said laminar flow to cover a non-planar surface of a component of said lithographic apparatus in a region of said part of said beam path.
Claim 11
Dependent Claim
26 words
Apparatus according to claim 9 wherein said cover member covers a non-planar surface of an element of one of said illumination system and said projection system.
Claim 12
Dependent Claim
31 words
Apparatus according to claim 7 wherein said material substantially transparent to said radiation is selected from the group comprising: CaF 2 , SiO 2 , MgF 2 and BaF 2 .
Claim 13
Dependent Claim
21 words
Apparatus according to claim 1 further comprising at least one flow control member provided in said part of said beam path.
Claim 14
Dependent Claim
34 words
Apparatus according to claim 1 wherein a speed of said laminar flow is greater than a maximum speed of movement of any moving parts in a region of said part of said beam path.
Claim 15
Dependent Claim
20 words
Apparatus according to claim 1 wherein a speed of said laminar flow is greater than a diffusion speed of air.
Claim 16
Dependent Claim
28 words
Apparatus according to claim 1 , wherein said flushing gas comprises one or more gases selected from the group comprising: N 2 , He, Ar, Kr, and Ne.
Claim 17
Dependent Claim
26 words
Apparatus according to claim 1 wherein said flushing gas in said part of said beam path has a contamination of air of less than 500 ppm.
Claim 18
Dependent Claim
19 words
Apparatus according to claim 1 wherein said flushing gas has an extinction coefficient, k, less than 0.005 per cm.
Claim 19
Dependent Claim
19 words
Apparatus according to claim 1 wherein said radiation of said projection beam has a wavelength less than 200 nm.
Claim 20
Independent Claim
99 words
A method of manufacturing a device comprising: providing a substrate having a radiation-sensitive layer in a projection apparatus; irradiating portions of a mask bearing a pattern with a projection beam of radiation and imaging said irradiated portions of the mask onto target portions of said substrate; and providing flushing gas to flow in a substantially laminar flow across at least a part of a path of said projection beam to displace therefrom ambient air, said flushing gas being substantially non-absorbent of said radiation, and said laminar flow of flushing gas traversing a substantially non-obstructed region in said projection apparatus.
Claim 21
Independent Claim
99 words
A method of manufacturing a device comprising: providing a substrate having a radiation-sensitive layer in a projection apparatus; irradiating portions of a mask bearing a pattern with a projection beam of radiation and imaging said irradiated portions of the mask onto target portions of said substrate; and providing flushing gas to flow in a substantially laminar flow across at least a part of a path of said projection beam to displace therefrom ambient air, said flushing gas being substantially non-absorbent of said radiation, and said laminar flow of flushing gas traversing a substantially non-obstructed region in said projection apparatus.
Claim 22
Dependent Claim
11 words
A device manufactured according to the method of claim 19 .
Claim 23
Dependent Claim
15 words
Apparatus according to claim 16 wherein said contamination of air is less than 100 ppm.
Claim 24
Dependent Claim
15 words
Apparatus according to claim 16 wherein said contamination of air is less than 10 ppm.
Claim 25
Dependent Claim
15 words
Apparatus according to claim 16 wherein said contamination of air is less than 1 ppm.
Claim 26
Dependent Claim
15 words
Apparatus according to claim 17 wherein said extinction coefficient is less than 0.001 per cm.
Claim 27
Dependent Claim
34 words
Apparatus according to claim 1 wherein said radiation of said projection beam has a wavelength selected from the group consisting of: between 152 nm and 162 nm and between 121 nm and 131 nm.
Claim 28
Dependent Claim
110 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas, in a vicinity of said first object table and said second object table, across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation.
Claim 29
Dependent Claim
110 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas, in a vicinity of said first object table and said second object table, across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation.
Claim 30
Dependent Claim
33 words
The apparatus according to claim 26 , wherein said gas structure comprises a gas flow regulator and an evacuator constructed and arranged to remove flushing gas from said part of said beam path.
Claim 31
Dependent Claim
30 words
The apparatus according to claim 26 , wherein said at least a part of the path includes a plurality of parts of said beam path substantially separated from each other.
Claim 32
Dependent Claim
40 words
The apparatus according to claim 26 , wherein said gas structure is arranged to provide separate laminar gas flows across a plurality of parts of said beam path, said parts of said beam path being substantially isolated from each other.
Claim 33
Dependent Claim
61 words
The apparatus according to claim 26 further comprising: at least one cover member formed of a material substantially transparent to said radiation, said cover member being substantially planar and provided substantially parallel to the direction of said laminar flow to cover a non-planar surface of a component of said lithographic apparatus in a region of said part of said beam path.
Claim 34
Dependent Claim
36 words
The apparatus according to claim 26 , wherein a speed of said laminar flow is greater than a maximum speed of movement of any moving parts in a region of said part of said beam path.
Claim 35
Dependent Claim
22 words
The apparatus according to claim 26 , wherein a speed of said laminar flow is greater than a diffusion speed of air.
Claim 36
Dependent Claim
105 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas, in a vicinity of said first object table, across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation.
Claim 37
Dependent Claim
105 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas, in a vicinity of said first object table, across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation.
Claim 38
Dependent Claim
33 words
The apparatus according to claim 33 , wherein said gas structure comprises a gas flow regulator and an evacuator constructed and arranged to remove flushing gas from said part of said beam path.
Claim 39
Dependent Claim
30 words
The apparatus according to claim 33 , wherein said at least a part of the path includes a plurality of parts of said beam path substantially separated from each other.
Claim 40
Dependent Claim
40 words
The apparatus according to claim 33 , wherein said gas structure is arranged to provide separate laminar gas flows across a plurality of parts of said beam path, said parts of said beam path being substantially isolated from each other.
Claim 41
Dependent Claim
61 words
The apparatus according to claim 33 further comprising: at least one cover member formed of a material substantially transparent to said radiation, said cover member being substantially planar and provided substantially parallel to the direction of said laminar flow to cover a non-planar surface of a component of said lithographic apparatus in a region of said part of said beam path.
Claim 42
Dependent Claim
36 words
The apparatus according to claim 33 , wherein a speed of said laminar flow is greater than a maximum speed of movement of any moving parts in a region of said part of said beam path.
Claim 43
Dependent Claim
22 words
The apparatus according to claim 33 , wherein a speed of said laminar flow is greater than a diffusion speed of air.
Claim 44
Dependent Claim
111 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure mounted to an extremity of at least one of said radiation system and said projection system, said gas structure is constructed and arranged to supply a laminar flow of flushing gas across at least a portion of a path of said projection beam, said flushing gas being substantially non-absorbent of said radiation.
Claim 45
Dependent Claim
111 words
A lithographic projection apparatus comprising: a radiation system constructed and arranged to supply a projection beam of radiation; a first object table for holding a mask; a second object table for holding a substrate; a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate; and a gas structure mounted to an extremity of at least one of said radiation system and said projection system, said gas structure is constructed and arranged to supply a laminar flow of flushing gas across at least a portion of a path of said projection beam, said flushing gas being substantially non-absorbent of said radiation.
Claim 46
Dependent Claim
47 words
The apparatus according to claim 40 , wherein said gas structure comprises an evacuator constructed and arranged to remove flushing gas from said part of said beam path in a vicinity of said extremity of said at least one of said radiation system and said projection system.
Claim 47
Dependent Claim
64 words
The apparatus according to claim 41 , wherein the structure of flushing gas is provided through an outlet mounted to an extremity of said at least one of said radiation system and said projection system and said evacuator is provided with an inlet facing said outlet and mounted to an extremity of said at least one of said radiation system and said projection system.
Claim 48
Dependent Claim
30 words
The apparatus according to claim 42 , wherein at least one of said inlet and said outlet comprises vanes configured and arranged to control the flow of said flushing gas.
Claim 49
Dependent Claim
36 words
The apparatus according to claim 40 , wherein a speed of said laminar flow is greater than a maximum speed of movement of any moving parts in a region of said part of said beam path.
Claim 50
Dependent Claim
22 words
The apparatus according to claim 40 , wherein a speed of said laminar flow is greater than a diffusion speed of air.
Claim 51
Dependent Claim
26 words
The method according to claim 19 , wherein said flushing gas is provided in a vicinity of at least one of the mask and the substrate.
Claim 52
Dependent Claim
57 words
The method according to claim 19 , wherein said flushing gas flows across at least one substantially transparent cover member covering a non-planar surface of a component of the projection apparatus in a region of said part of said beam path, the cover member being substantially planar and substantially parallel to the direction of said laminar flow.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2006-04-28 | 2006-10-28 | 2007-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2010-04-28 | 2010-10-28 | 2011-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2014-04-28 | 2014-10-28 | 2015-04-29 | $7700.00 | Window Closed / Lapsed |