# US 6,724,004 B2 · Method and apparatus for elimination of high energy ion from EUV radiating device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,724,004 B2 - Document ID: US6724004B2 - Status: Granted - Kind: B2 - Application number: 10/279,854 - Filed: 2002-10-25 - Published: 2003-05-01 - Granted: 2004-04-20 - Earliest claimed: 2001-10-25 - Assignees: National Institute of Advanced Industrial Science and Technology - Inventors: Hidehiko Yashiro - Web page: https://patentgrep.com/patent/US6724004B2 ## CPC - H05G 2/0086: {Optical arrangements for conveying the laser beam to the plasma generation location} - B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic - G03F 7/70033: {by plasma extreme ultraviolet [EUV] sources} - G03F 7/70916: {Pollution mitigation, i.e. mitigating effect of contamination or debris, e.g. foil traps} - H05G: X-RAY TECHNIQUE (investigating or analysing materials by the use of X-rays G01N23/00; apparatus for X-ray photography G03B42/02; X-ray tubes H01J35/00; TV systems having X-ray input H04N5/321) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) ## Abstract A method for the elimination of high-energy ion in an EUV light-radiating device includes irradiating a first target with a first exciting laser to produce a laser-produced plasma EUV light source and causing a high-energy ion generated simultaneously with EUV light to collide against plasma produced by irradiating a second target with a second laser to separate the high-energy ion from the orbit of the EUV light. An apparatus for the elimination of a high-energy ion in an EUV light-radiating device includes a device for irradiating a first target with a first exciting laser to produce a plasma EUV light source and induce emission of EUV light, a device for irradiating a second target with a second laser to produce plasma, and a device for causing a high-energy ion generated simultaneously with the EUV light to be delayed by difference between an ion flight time and plasma expansion time for ion elimination and collide against the plasma to separate the high-energy ion from the orbit of the EUV light. ## Claims ### Claim 1 A method for the elimination of a high-energy ion in an EUV light-radiating device, which comprises irradiating a first target with a first exciting laser to produce a laser-produced plasma EUV light source and causing a high-energy ion generated simultaneously with EUV light to collide against plasma produced by irradiating a second target with a second laser to separate said high-energy ion from an orbit of said EUV light. ### Claim 2 (depends on 1) The method according to claim 1, wherein said plasma EUV light source is pinch plasma or discharge plasma entrapped in a capillary tube. ### Claim 3 (depends on 1) The method according to claim 1, which further comprises effecting passage of said EUV light and subsequently causing said high-energy ion entrained by said EUV light to collide against said plasma. ### Claim 4 An apparatus for the elimination of a high-energy ion in an EUV light-radiating device, comprising means for irradiating a first target with a first exciting laser to produce a plasma EUV light source and induce emission of EUV light, means for irradiating a second target with a second laser to produce plasma, and means for effecting passage of said EUV light and subsequently causing said high-energy ion entrained by said EUV light to collide against said plasma to separate said high-energy ion from an orbit of said EUV light. ### Claim 5 (depends on 4) The apparatus according to claim 4, wherein said plasma is pinch plasma or discharge plasma entrapped in a capillary tube. ### Claim 6 (depends on 4) The apparatus according to claim 4, wherein said second target is formed of any one of elements Si, Ar, Zn, Ga, Kr, Mo, In, Sn, Xe, Pb and Hg, or a compound having any one of the elements as a principal component thereof. ### Claim 7 (depends on 4) The apparatus according to claim 4, wherein said first target is formed of any one of elements B, C, Al, Cu, Xe and Sn, or a compound having any one of the elements as a principal component thereof. ### Claim 8 (depends on 5) The apparatus according to claim 5, wherein said pinch or discharge plasma is formed of Xe, Sn or a Sn compound. ### Claim 9 (depends on 4) The apparatus according to claim 4, wherein said plasma is produced by condensing said laser in a form of discrete column on said second target. ### Claim 10 (depends on 4) The apparatus according to claim 4, wherein said plasma is produced in a planar shape by condensing said laser linearly on said second target. ### Claim 11 (depends on 4) The apparatus according to claim 4, wherein said second target is inclined at a predetermined angle to prevent an ion issuing from said plasma from entering an object for irradiation with said EUV light in a solid angle. ### Claim 12 (depends on 4) The apparatus according to claims 4, further comprising a plate interposed between said plasma and an object for irradiation with said EUV light so as to prevent an ion issuing from said plasma from entering said object in a solid angle. ### Claim 13 (depends on 4) The apparatus according to claim 4, further comprising partitioning walls disposed in front of an object for irradiation with said EUV light so that said high-energy ion collides initially against said plasma and subsequently against said partitioning walls and keeps from reaching said object. ### Claim 14 (depends on 13) The apparatus according to claim 13, wherein said partitioning walls are formed of a plurality of plates disposed at predetermined intervals. ### Claim 15 (depends on 13) The apparatus according to claim 13, wherein said partitioning walls are formed of a bundle of plural cones. ### Claim 16 (depends on 13) The apparatus according to claim 13, wherein each of said partitioning walls is formed of a large-diameter cone and a small-diameter cone accommodated in said large-diameter cone.