# US 2018/0323048 A1 · Flexible adjustable return path magnet assembly and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0323048 A1 - Document ID: US20180323048A1 - Status: Published application - Kind: A1 - Application number: 15/969,919 - Filed: 2018-05-03 - Published: 2018-11-08 - Earliest claimed: 2017-05-04 - Assignees: Cardinal CG Company - Applicants: Cardinal CG Company - Inventors: Klaus H.W. Hartig - Web page: https://patentgrep.com/patent/US20180323048A1 ## CPC - H01J 37/3455: {Movable magnets} - C23C 14/35: by application of a magnetic field, e.g. magnetron sputtering {(C23C14/3457 takes precedence)} - H01J 37/34: operating with cathodic sputtering (H01J37/36 takes precedence {; methods of cathodic sputtering C23C14/34}) - H01J 37/3408: {Planar magnetron sputtering} - H01J 37/345: {Magnet arrangements in particular for cathodic sputtering apparatus (material of magnets or magnets in general H01F1/00, H01F7/00)} - H01J 37/3461: {Means for shaping the magnetic field, e.g. magnetic shunts} - 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) ## Abstract The invention provides a sputter deposition assembly that includes a sputtering chamber, a sputtering target, and a magnet assembly. The magnet assembly includes a magnetic backing plate comprising an elongated flexible magnetic control body or a plurality of layered metal sheets. ## Claims ### Claim 1 A sputter deposition assembly comprising a sputtering chamber, a sputtering target, and a magnet assembly, the magnet assembly being mounted adjacent to a rear surface of the sputtering target, the magnet assembly comprising a magnetic backing plate and spaced-apart first and second permanent magnets, the first and second permanent magnets each having a proximal end and a distal end, the distal end being further from the sputtering target than is the proximal end, the magnet assembly creating a magnetic field comprising field lines that extend from the proximal end of the first permanent magnet, through the sputtering target, along an arc located in front of the sputtering target, back through the sputtering target, into the proximal end of the second permanent magnet, through the second permanent magnet, along a return path, and to the distal end of the first permanent magnet, the return path passing through the magnetic backing plate of the magnet assembly, the magnetic backing plate defining a gap, the magnet assembly further comprising an elongated flexible magnetic control body mounted so as to project into the gap, the elongated flexible magnetic control body having a length and being differentially bendable along the length so as to project further into the gap at one position along the length than at another position along the length. ### Claim 2 (depends on 1) The sputter deposition assembly of claim 1 wherein the sputter deposition assembly is configured such that the arc of the magnetic field lines located in front of the sputtering target changes in strength, configuration, or both in response to bending the elongated flexible magnetic control body so that the elongated flexible magnetic control body projects to a greater or lesser extent into the gap at one or more desired positions along the length. ### Claim 3 (depends on 1) The sputter deposition assembly of claim 1 wherein the magnetic backing plate comprises two plate segments having confronting ends that bound the gap, the elongated flexible magnetic control body having two generally opposed engagement faces, the elongated flexible magnetic control body being differentially bendable such that an extent to which it projects into the gap at different points along the length is locally adjustable between first and second configurations, the first configuration characterized by the two engagement faces of the elongated flexible magnetic control body contacting the confronting ends of the two plate segments, the second configuration characterized by the two engagement faces of the elongated flexible magnetic control body being spaced apart from the confronting ends of the two plate segments. ### Claim 4 (depends on 1) The sputter deposition assembly of claim 1 wherein the elongated flexible magnetic control body is constructed to bend differentially along the length so as to define a continuous profile devoid of step-like transitions along the length of the elongated flexible magnetic control body. ### Claim 5 (depends on 1) The sputter deposition assembly of claim 1 wherein the elongated flexible magnetic control body comprises a ferromagnetic fluid contained within a bendable wall. ### Claim 6 (depends on 5) The sputter deposition assembly of claim 5 wherein the ferromagnetic fluid comprises both oil and steel particles. ### Claim 7 (depends on 1) The sputter deposition assembly of claim 1 wherein the magnet assembly is configured in a racetrack arrangement that includes: (i) two generally parallel elongated side regions, and (ii) two curved turnaround regions at opposite ends of the racetrack arrangement, each curved turnaround region having a length, the elongated flexible magnetic control body spanning at least a portion of the length of one of the two curved turnaround regions such that the length of the elongated flexible magnetic control body extends along a curved path. ### Claim 8 (depends on 7) The sputter deposition assembly of claim 7 wherein the elongated flexible magnetic control body spans at least substantially the entire length of one of the two curved turnaround regions. ### Claim 9 (depends on 1) The sputter deposition assembly of claim 1 wherein the magnet assembly further includes an actuator system comprising a series of adjustments spaced apart along the length, the adjustments configured such that the elongated flexible magnetic control body bends locally, so as to project different extents into the gap at different points along the length, in response to operation of one or more of the adjustments. ### Claim 10 (depends on 9) The sputter deposition assembly of claim 9 wherein each of the adjustments is coupled to a motor configured to move such adjustment selectively toward or away from the sputtering target, the sputter deposition assembly further comprising a control unit connected with each said motor to control movement of the adjustments, the control unit being located at a position external to the sputtering chamber, whereby an operator can initiate movement of the adjustments from outside the sputtering chamber without having to open the sputtering chamber. ### Claim 11 A sputter deposition assembly comprising a sputtering chamber, a sputtering target, and a magnet assembly, the magnet assembly being mounted adjacent to a rear surface of the sputtering target, the magnet assembly comprising a magnetic backing plate and spaced-apart first and second permanent magnets, the first and second permanent magnets each having a proximal end and a distal end, the distal end being further from the sputtering target than is the proximal end, the magnet assembly creating a magnetic field comprising field lines that extend from the proximal end of the first permanent magnet, through the sputtering target, along an arc located in front of the sputtering target, back through the sputtering target, into the proximal end of the second permanent magnet, through the second permanent magnet, along a return path, and to the distal end of the first permanent magnet, the return path passing through the magnetic backing plate of the magnet assembly, the magnetic backing plate comprising a plurality of layered metal sheets each formed of ferromagnetic or ferrimagnetic material. ### Claim 12 (depends on 11) The sputter deposition assembly of claim 11 wherein the layered metal sheets are carried alongside one another in a layered arrangement having opposed first and second sides, the layered arrangement characterized by the layered metal sheets being locked in permanent contact with one another at the first side whereas at the second side the layered arrangement is expandable such that at least one of the layered metal sheets is configured to bend away from at least another of the layered metal sheets in response to operation of an actuator. ### Claim 13 (depends on 11) The sputter deposition assembly of claim 11 wherein the plurality of layered metal sheets comprises first and second metal sheets each having opposed first and second faces, the first face of the first metal sheet being in contact with both the distal end of the first permanent magnet and the distal end of the second permanent magnet, the second metal sheet having opposed first and second faces, the second metal sheet being separated from the first and second permanent magnets by at least the first metal sheet. ### Claim 14 (depends on 13) The sputter deposition assembly of claim 13 wherein the second metal sheet is a flexible metal leaf. ### Claim 15 (depends on 14) The sputter deposition assembly of claim 14 wherein the sputter deposition assembly is configured such that the arc of the magnetic field lines located in front of the sputtering target changes in strength, configuration, or both in response to bending of the second metal sheet away from the first metal sheet. ### Claim 16 (depends on 13) The sputter deposition assembly of claim 13 wherein the layered metal sheets extend from a first side adjacent the first permanent magnet to a second side adjacent the second permanent magnet. ### Claim 17 (depends on 16) The sputter deposition assembly of claim 16 wherein the layered metal sheets are carried alongside one another in a layered arrangement characterized by the layered metal sheets being locked in permanent contact with one another at the first side whereas at the second side the layered arrangement is expandable such that at least the second metal sheet is configured to bend away from the first metal sheet in response to operation of an actuator. ### Claim 18 (depends on 17) The sputter deposition assembly of claim 17 wherein the layered arrangement at the second side is adjustable between first and second configurations, the first configuration being a compact configuration characterized by the layered metal sheets being in contact with one another at the second side, the second configuration being an expanded configuration characterized by the layered metal sheets being spaced apart from one another at the second side, the sputter deposition assembly being configured such that the arc of the magnetic field lines located in front of the sputtering target changes in strength, configuration, or both in response to adjustment of the layered arrangement at the second side between the first and second configurations. ### Claim 19 (depends on 17) The sputter deposition assembly of claim 17 wherein the plurality of layered metal sheets comprises first, second, and third metal sheets, the first configuration being a compact configuration characterized by the first metal sheet being in contact with the second metal sheet at the second side while the second metal sheet is in contact with the third metal sheet at the second side, the second configuration being an expanded configuration characterized by the first metal sheet being spaced apart from the second metal sheet at the second side while the second metal sheet is spaced apart from the third metal sheet at the second side. ### Claim 20 (depends on 17) The sputter deposition assembly of claim 17 wherein the actuator comprises a threaded shaft extending through all of the layered metal sheets, the threaded shaft being coupled to a motor configured to rotate such threaded shaft, the sputter deposition assembly further comprising a control unit connected with the motor to control rotation of the threaded shaft, the control unit being located at a position external to the sputtering chamber, whereby an operator can initiate bending of at least one of the layered metal sheets from outside the sputtering chamber without having to open the sputtering chamber.