# US 10,504,705 B2 · Physical vapor deposition chamber with static magnet assembly and methods of sputtering > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,504,705 B2 - Document ID: US10504705B2 - Status: Granted - Kind: B2 - Application number: 15/706,129 - Filed: 2017-09-15 - Published: 2019-03-21 - Granted: 2019-12-10 - Earliest claimed: 2017-09-15 - Assignees: Applied Materials, Inc. - Applicants: Applied Materials, Inc. - Inventors: Sirisha Behara; Sanjay Bhat; Vibhu Jindal - Web page: https://patentgrep.com/patent/US10504705B2 ## CPC - H01J 37/3408: {Planar magnetron sputtering} - C23C 14/185: {by cathodic sputtering} - C23C 14/3407: {Cathode assembly for sputtering apparatus, e.g. Target} - C23C 14/35: by application of a magnetic field, e.g. magnetron sputtering {(C23C14/3457 takes precedence)} - C23C 14/352: {using more than one target (C23C14/56 takes precedence)} - G03F 1/24: Reflection masks; Preparation thereof - H01J 37/345: {Magnet arrangements in particular for cathodic sputtering apparatus (material of magnets or magnets in general H01F1/00, H01F7/00)} - H01J 37/3452: {Magnet distribution} - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - 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 Magnetrons for plasma sputter chambers, plasma sputter chambers including magnetrons and methods of processing a substrate such as an EUV mask blank in a plasma sputter chamber are disclosed. The magnetron comprises a plurality of elongate magnets arranged in a pattern where there is an unbalance ratio greater than 1 and less than 3. ## Claims ### Claim 1 A magnetron for a plasma sputter chamber comprising: a magnetron comprising an outer pole, a first inner pole and a second inner pole positionable at a back of a sputtering target in a fixed relationship with the target; the outer pole comprising a plurality of first elongate magnets of a first magnetic polarity, the first elongate magnets mounted on a magnetic yoke arranged in a first closed pattern around a central region; the first inner pole disposed within the first closed pattern, separated from the outer pole by a gap, comprising a plurality of second elongate magnets of a second magnetic polarity opposite the first magnetic polarity arranged in a second closed pattern mounted on the magnetic yoke; and the second inner pole disposed in the central region and surrounded by the second closed pattern, separated from the first inner pole by a gap, comprising at least one of a third elongate magnet of the first magnetic polarity mounted on the magnetic yoke, the poles arranged such that there is an unbalance ratio defined by a total magnetic intensity of poles of magnets of the first polarity to the total magnetic intensity of poles of magnets of the second polarity and the unbalance ratio is greater than 1 and less than 3. ### Claim 2 (depends on 1) The magnetron of claim 1, wherein the first closed pattern and the second closed pattern are substantially circular. ### Claim 3 (depends on 1) The magnetron of claim 1, wherein the unbalance ratio is in a range of 1.5 to 2.5. ### Claim 4 (depends on 2) The magnetron of claim 2, wherein the magnetron includes three or less poles selected from the outer pole, the first inner pole and the second inner pole. ### Claim 5 (depends on 2) The magnetron of claim 2, wherein the second inner pole comprises a single magnet. ### Claim 6 (depends on 2) The magnetron of claim 2, wherein the second inner pole comprises a plurality of magnets arranged in a circular pattern. ### Claim 7 (depends on 2) The magnetron of claim 2, wherein the magnetron has a diameter in a range of 5.5 inches and 8.5 inches. ### Claim 8 (depends on 2) The magnetron of claim 2, wherein the elongate magnets are substantially cylindrical having a length and a diameter, and there is a ratio of length to diameter greater than 2:1. ### Claim 9 A plasma sputter chamber comprising: a chamber wall defining a processing volume within the plasma sputter chamber; a magnetron comprising an outer pole, a first inner pole and a second inner pole positionable at a back of a sputtering target in a fixed relationship with the target; the outer pole comprising a plurality of first elongate magnets of a first magnetic polarity, the first elongate magnets mounted on a magnetic yoke arranged in a first closed pattern around a central region; the first inner pole disposed within the first closed pattern, separated from the outer pole by a gap, comprising a plurality of second elongate magnets of a second magnetic polarity opposite the first magnetic polarity arranged in a second closed pattern mounted on the magnetic yoke; and the second inner pole disposed in the central region and surrounded by the second closed pattern, separated from the first inner pole by a gap, comprising at least one of a third elongate magnet of the first magnetic polarity mounted on the magnetic yoke, the outer pole, the first inner pole and the second inner pole arranged such that there is an unbalance ratio defined by a total magnetic intensity of poles of magnets of the first polarity to the total magnetic intensity of poles of magnets of the second polarity and the unbalance ratio is greater than 1 and less than 3. ### Claim 10 (depends on 9) The plasma sputter chamber of claim 9, wherein the first closed pattern and the second closed pattern are substantially circular. ### Claim 11 (depends on 9) The plasma sputter chamber of claim 9, wherein the unbalance ratio is in a range of 1.5 to 2.5. ### Claim 12 (depends on 10) The plasma sputter chamber of claim 10, wherein the magnetron includes three or less poles selected from the outer pole, the first inner pole and the second inner pole. ### Claim 13 (depends on 10) The plasma sputter chamber of claim 10, wherein the second inner pole comprises a single magnet. ### Claim 14 (depends on 10) The plasma sputter chamber of claim 10, wherein the second inner pole comprises a plurality of magnets arranged in a circular pattern. ### Claim 15 (depends on 10) The plasma sputter chamber of claim 10, wherein the magnetron has a diameter in a range of 5.5 inches and 8.5 inches. ### Claim 16 (depends on 10) The plasma sputter chamber of claim 10, wherein the elongate magnets are substantially cylindrical having a length and a diameter, and there is a ratio of length to diameter greater than 2:1. ### Claim 17 A method of processing a substrate in a plasma sputter chamber chamber, the method comprising: placing a substrate on a substrate support within a processing volume of the plasma sputter chamber defined by a chamber wall, the processing volume including an upper portion and a lower portion, the substrate support in the lower portion; the upper portion including a magnetron comprising an outer pole, a first inner pole and a second inner pole positionable at a back of a sputtering target in a fixed relationship with the target; the outer pole comprising a plurality of first elongate magnets of a first magnetic polarity, the first elongate magnets mounted on a magnetic yoke arranged in a first closed pattern around a central region; the first inner pole disposed within the first closed pattern, separated from the outer pole by a gap, comprising a plurality of second elongate magnets of a second magnetic polarity opposite the first magnetic polarity arranged in a second closed pattern mounted on the magnetic yoke; and the second inner pole disposed in the central region and surrounded by the second closed pattern, separated from the first inner pole by a gap, comprising at least one of a third elongate magnet of the first magnetic polarity mounted on the magnetic yoke, the poles arranged such that there is an unbalance ratio defined by a total magnetic intensity of poles of magnets of the first polarity to the total magnetic intensity of poles of magnets of the second polarity and the unbalance ratio is greater than 1 and less than 3; and sputtering material from the target comprising source material located above the substrate support in the upper portion onto a substrate. ### Claim 18 (depends on 17) The method of claim 17, wherein the magnetron includes three or less poles selected from the outer pole, the first inner pole and the second inner pole and the target has a diameter in a range of 5.5 inches and 8.5 inches. ### Claim 19 (depends on 18) The method of claim 18, wherein the substrate is a low thermal expansion substrate for use as an EUV mask blank and the source material is selected from molybdenum, silicon, and tantalum-containing material, and the method comprises depositing a multilayer stack of alternating layers of molybdenum and silicon and depositing an EUV absorbing layer comprising tantalum. ### Claim 20 (depends on 19) The method of claim 19, wherein the plasma sputter chamber contains a first sputtering target comprising silicon, a second target comprising molybdenum, and a third target comprising tantalum, the method comprising depositing the multilayer stack by alternately sputtering the first target and the second target and then sputtering the third target to form a layer comprising tantalum on the multilayer stack.