# US 12,243,708 B2 · Ion generator and ion implanter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,243,708 B2 - Document ID: US12243708B2 - Status: Granted - Kind: B2 - Application number: 18/505,522 - Filed: 2023-11-09 - Published: 2024-03-07 - Granted: 2025-03-04 - Earliest claimed: 2019-03-18 - Assignees: Sumitomo Heavy Industries Ion Technology Co., Ltd. - Applicants: Sumitomo Heavy Industries Ion Technology Co., Ltd. - Inventors: Syuta Ochi - Web page: https://patentgrep.com/patent/US12243708B2 ## CPC - H01J 37/08: Ion sources; Ion guns - H01J 37/063: Geometrical arrangement of electrodes for beam-forming - H01J 37/3171: {for ion implantation} - H01J 37/32055: {Arc discharge} - H01J 37/32357: {Generation remote from the workpiece, e.g. down-stream} - H01J 37/32385: {Treating the edge of the workpieces} - H01J 37/32422: {Arrangement for selecting ions or species in the plasma} - H01J 37/32788: {for extracting the material from the process chamber} - H01J 2237/032: Mounting or supporting - H01J 2237/061: Construction - H01J 2237/082: Electron beam - H01J 2237/31705: Impurity or contaminant control - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) ## Abstract An ion generator includes an arc chamber defining a plasma generation space, and a cathode which emits thermoelectrons toward the plasma generation space. The arc chamber includes a box-shaped main body having an opening, and a slit member mounted to cover the opening and provided with a front slit. An inner surface of the main body is exposed to the plasma generation space made of a refractory metal material. The slit member includes an inner member made of graphite and an outer member made of another refractory metal material. The outer member includes an outer surface exposed to an outside of the arc chamber. The inner member includes an inner surface exposed to the plasma generation space, and an opening portion which forms the front slit extending from the inner surface of the inner member to the outer surface of the outer member. ## Claims ### Claim 1 An ion implanter comprising: a beam generation unit that comprises an ion generator to generate ions, and that generates an ion beam of the ions extracted from the ion generator; and a substrate processing unit in which the ion beam is implanted into a substrate, wherein the ion generator includes an arc chamber which defines a plasma generation space, the arc chamber includes a box-shaped main body which includes an opening in at least a part of a front side of the main body, and a slit member which is mounted to cover the opening of the front side of the main body and provided with a front slit for extracting ions, an inner surface of the main body which is exposed to the plasma generation space is made of a first refractory metal material, and an inner surface of the slit member which is exposed to the plasma generation space is made of graphite. ### Claim 2 (depends on 1) The ion implanter according to claim 1, wherein the ion generator further incudes a cathode which emits thermoelectrons toward the plasma generation space. ### Claim 3 (depends on 2) The ion implanter according to claim 2, wherein the cathode is fixed in a state where it is electrically insulated from the arc chamber. ### Claim 4 (depends on 3) The ion implanter according to claim 3, wherein the cathode includes a portion made of a second refractory metal material. ### Claim 5 (depends on 4) The ion implanter according to claim 4, wherein the cathode has a filament that generate primary thermoelectrons and a cathode head that generates secondary thermoelectrons by heating with the primary thermoelectrons, and wherein the cathode head is made of the second refractory metal material. ### Claim 6 (depends on 5) The ion implanter according to claim 5, wherein a content rate of a refractory metal element by weight in the second refractory metal material is higher than a content rate of a refractory metal element by weight in the first refractory metal material. ### Claim 7 An ion implanter comprising: a beam generation unit that comprises an ion generator to generate multiply charged ions, and that generates an ion beam of the multiply charged ions extracted from the ion generator; a beam acceleration unit that accelerates the ion beam to obtain a high energy ion beam of 1 MeV or more; and a substrate processing unit in which the high-energy ion beam is implanted into a substrate, wherein the ion generator includes an arc chamber which defines a plasma generation space, and a cathode which emits thermoelectrons toward the plasma generation space, the arc chamber includes a box-shaped main body which includes an opening in at least a part of a front side of the main body, and a slit member which is mounted to cover the opening of the front side of the main body and provided with a front slit for extracting ions, an inner surface of the main body which is exposed to the plasma generation space is made of a first refractory metal material, an inner surface of the slit member which is exposed to the plasma generation space is made of graphite, the cathode including a portion made of a second refractory metal material, and a content rate of a refractory metal element by weight in the second refractory metal material is higher than a content rate of a refractory metal element by weight in the first refractory metal material. ### Claim 8 (depends on 7) The ion implanter according to claim 7, wherein the beam acceleration unit comprises a linear accelerator. ### Claim 9 (depends on 7) The ion implanter according to claim 7, wherein the beam acceleration unit comprises a plurality of linear accelerators. ### Claim 10 (depends on 7) The ion implanter according to claim 7, wherein the beam acceleration unit accelerates the ion beam to obtain a high energy ion beam of 4 MeV or more. ### Claim 11 (depends on 7) The ion implanter according to claim 7, wherein the ion generator generates the multiply charged ions of at least one of boron, phosphorus, and arsenic. ### Claim 12 An ion implanter comprising an ion generator, wherein the ion generator comprises arc chamber which defines a plasma generation space and a cathode which emits thermoelectrons toward the plasma generation space, wherein the arc chamber has a front slit for extracting ions, wherein at least part of an inner surface of the arc chamber which is exposed to the plasma generation space is made of a first refractory metal material, wherein the cathode has a filament that generate primary thermoelectrons and a cathode head that generates secondary thermoelectrons by heating with the primary thermoelectrons, wherein the cathode head is made of a second refractory metal material, and wherein a content rate of a refractory metal element by weight in the first refractory metal material is lower than a content rate of a refractory metal element by weight in the second refractory metal material. ### Claim 13 (depends on 12) The ion implanter according to claim 12, wherein the cathode is fixed in a state where it is electrically insulated from the arc chamber. ### Claim 14 (depends on 12) The ion implanter according to claim 12, wherein each of the first refractory metal material and the second refractory metal material includes at least one of tungsten, molybdenum, and tantalum.