# US 11,908,659 B2 · Multi charged particle beam writing apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,908,659 B2 - Document ID: US11908659B2 - Status: Granted - Kind: B2 - Application number: 17/805,887 - Filed: 2022-06-08 - Published: 2022-12-15 - Granted: 2024-02-20 - Earliest claimed: 2021-06-14 - Assignees: NuFlare Technology, Inc. - Applicants: NuFlare Technology, Inc. - Inventors: Toshiki Kimura; Hirofumi Morita; Takanao Touya; Mitsuhiro Okazawa - Web page: https://patentgrep.com/patent/US11908659B2 ## CPC - H01J 37/3177: {Multi-beam, e.g. fly's eye, comb probe} - H01J 37/045: {Beam blanking or chopping, i.e. arrangements for momentarily interrupting exposure to the discharge} - H01J 37/09: Diaphragms; Shields associated with electron or ion-optical arrangements; Compensation of disturbing fields - H01J 2237/0264: magnetic - H01J 2237/0435: Multi-aperture - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) ## Abstract In one embodiment, a multi charged particle beam writing apparatus includes a blanking aperture array substrate provided with a plurality of blankers configured to respectively perform blanking deflection on a plurality of charged particle beams included in a multi-beam, and a first shield member which is disposed downstream of the blanking aperture array substrate with respect to a travel direction of the multi-beam, has a cylindrical part in which the multi-beam passes through, and is composed of a high magnetic permeability material. ## Claims ### Claim 1 A multi charged particle beam writing apparatus comprising: a blanking aperture array substrate provided with a plurality of blankers configured to respectively perform blanking deflection on a plurality of charged particle beams included in a multi-beam; and a first shield member which is disposed downstream of the blanking aperture array substrate with respect to a travel direction of the multi-beam, has a cylindrical part in which the multi-beam passes through, and is composed of a high magnetic permeability material. ### Claim 2 (depends on 1) The apparatus according to claim 1, wherein the first shield member is connected to other shield members directly or via a connection member composed of a high magnetic permeability material. ### Claim 3 (depends on 1) The apparatus according to claim 1, further comprising a flat plate-shaped second shield member which is disposed upstream of the blanking aperture array substrate with respect to the travel direction of the multi-beam, has a circular opening through which the multi-beam passes, and is composed of a high magnetic permeability material. ### Claim 4 (depends on 3) The apparatus according to claim 3, wherein in the second shield member, the circular opening is formed in a central portion of a flat rectangular plate in a plan view, and a length of one side of the rectangular plate is 23 mm or more and 140 mm or less, and a diameter of the circular opening is 22.6 mm or more and 50 mm or less. ### Claim 5 (depends on 3) The apparatus according to claim 3, wherein the second shield member has an annular shape. ### Claim 6 (depends on 5) The apparatus according to claim 5, wherein a thickness of the second shield member is 0.1 mm or more and 5 mm or less, an inner diameter is 23 mm or more and 50 mm or less, and an outer diameter is 24 mm or more and 100 mm or less. ### Claim 7 (depends on 3) The apparatus according to claim 3, further comprising a shaping aperture array substrate including a plurality of openings, and configured to form the multi-beam by allowing parts of a charged particle beam to pass through the plurality of openings, wherein the second shield member is disposed between the shaping aperture array substrate and the blanking aperture array substrate. ### Claim 8 (depends on 1) The apparatus according to claim 1, further comprising a flat plate-shaped third shield member which is disposed between the blanking aperture array substrate and the first shield member, has a circular opening through which the multi-beam passes, and is composed of a high magnetic permeability material. ### Claim 9 (depends on 8) The apparatus according to claim 8, wherein the third shield member has an annular shape. ### Claim 10 (depends on 9) The apparatus according to claim 9, wherein a thickness of the third shield member is 0.1 mm or more and 5 mm or less, an inner diameter is 23 mm or more and 50 mm or less, and an outer diameter is 24 mm or more and 100 mm or less. ### Claim 11 (depends on 8) The apparatus according to claim 8, further comprising a ring-shaped fourth shield member which is disposed between the blanking aperture array substrate and the third shield member, and composed of a high magnetic permeability material. ### Claim 12 (depends on 1) The apparatus according to claim 1, wherein the first shield member has a first cylindrical part, and a second cylindrical part having an inner diameter greater than an inner diameter of the first cylindrical part, and a lower edge of the first cylindrical part and an upper edge of the second cylindrical part are connected. ### Claim 13 (depends on 12) The apparatus according to claim 12, wherein a thickness of the first shield member is 0.1 mm or more and 5 mm or less, an inner diameter of the first cylindrical part is 18 mm or more and 70 mm or less, a height of the first cylindrical part is 0.3 mm or more and 30 mm or less, and a height of the second cylindrical part is 1 mm or more and 100 mm or less. ### Claim 14 (depends on 1) The apparatus according to claim 1, wherein the first shield member is composed of alloy containing iron, nickel or cobalt which have a relative magnetic permeability of 1 or more. ### Claim 15 (depends on 14) The apparatus according to claim 14, wherein the first shield member is composed of permalloy. ### Claim 16 (depends on 3) The apparatus according to claim 3, further comprising: a flat plate-shaped third shield member which is disposed between the blanking aperture array substrate and the first shield member, has a circular opening through which the multi-beam passes, and is composed of a high magnetic permeability material; and a ring-shaped fourth shield member which is disposed between the blanking aperture array substrate and the third shield member, and is composed of a high magnetic permeability material.