# US 2019/0169742 A1 · GAS PIPING SYSTEM, CHEMICAL VAPOR DEPOSITION DEVICE, FILM DEPOSITION METHOD, AND METHOD FOR PRODUCING SiC EPITAXIAL WAFER > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0169742 A1 - Document ID: US20190169742A1 - Status: Published application - Kind: A1 - Application number: 16/314,084 - Filed: 2017-06-12 - Published: 2019-06-06 - Earliest claimed: 2016-07-07 - Assignees: Showa Denko K.K. - Applicants: Showa Denko K.K. - Inventors: Naoto ISHIBASHI; Keisuke FUKADA; Tomoya UTASHIRO; Akira BANDO - Web page: https://patentgrep.com/patent/US20190169742A1 ## CPC - C23C 16/455: characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber - C23C 16/325: {Silicon carbide} - C23C 16/4412: {Details relating to the exhausts, e.g. pumps, filters, scrubbers, particle traps} - C23C 16/45561: {Gas plumbing upstream of the reaction chamber} - C30B 25/14: Feed and outlet means for the gases; Modifying the flow of the reactive gases - C30B 29/36: Carbides - H10P 14/24: using chemical vapour deposition [CVD] - H10P 14/3408: {Silicon carbide} - H10P 14/3442: {N-type} - H10P 14/3444: {P-type} - 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) - C30B: SINGLE-CRYSTAL GROWTH (by using ultra-high pressure, e.g. for the formation of diamonds, B01J3/06); UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL (zone-refining of metals or alloys C22B); PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (casting of metals, casting of other substances by the same processes or devices B22D; working of plastics B29; modifying the physical structure of metals or alloys C21D, C22F); SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (for producing semiconductor devices or parts thereof H10); APPARATUS THEREFOR - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract This gas piping system is a run-vent mode gas piping system in which, the gas piping system including a plurality of supply lines through which plural gases are fed individually, an exhaust line that leads from a reactor to an exhaust pump, a run line having one or plural pipes which respectively branch from the plural supply lines, plural vent lines which respectively branch from the supply lines and are connected to the exhaust line, and plural valves which are respectively provided at the branch points of the plural supply lines, and switches between feeding a gas to the run line side and feeding a gas to the vent line side, wherein the plural vent lines are separated from each other until the vent lines reach the exhaust line, and the inner diameter of the exhaust line is greater than the inner diameter of the plural vent lines. ## Claims ### Claim 1 A run-vent mode gas piping system in which a plurality of gases are supplied to an inside of a reactor in which vapor deposition is performed, the gas piping system comprising: a plurality of supply lines through which the plurality of gases are fed individually, an exhaust line that leads from an exhaust port of the reactor to an exhaust pump, a run line which has one or a plurality of pipes which respectively branch from the plurality of supply lines to supply the plurality of gases to the reactor, a plurality of vent lines which respectively branch from the plurality of supply lines and are connected to the exhaust line, and a plurality of valves which are respectively provided at branch points of the plurality of supply lines, and switches between feeding a gas to the run line side and feeding a gas to the vent line side, wherein the plurality of vent lines are separated from each other until the vent lines reach the exhaust line, and an inner diameter of the exhaust line is greater than an inner diameter of each of the plurality of vent lines. ### Claim 2 (depends on 1) The gas piping system according to claim 1, wherein the pipes, which connect with the branch points, join together before the pipes reach the reactor. ### Claim 3 (depends on 1) The gas piping system according to claim 1, wherein among the plurality of vent lines, at least one vent line is connected to the exhaust line, and remaining vent lines are each connected to a separate exhaust pump which is provided independently. ### Claim 4 (depends on 1) The gas piping system according to claim 1, wherein a pipe inner diameter of the exhaust line is 3 cm or greater at connection points where the exhaust line connect with each of the plurality of vent lines. ### Claim 5 (depends on 1) A chemical vapor deposition device comprising the gas piping system according to claim 1, and a reactor that is connected to the gas piping system. ### Claim 6 (depends on 5) A film deposition method that uses the chemical vapor deposition device according to claim 5, the method comprising sending deposit-causing gases, which produce a solid compound upon mutual reaction at normal temperature, through the vent lines which are independent and are mutually separated. ### Claim 7 (depends on 6) The film deposition method according to claim 6, wherein regarding the exhaust line to which the plurality of vent lines connect, a gas concentration of each of the deposit-causing gases is 5% or less of that of total gas which flows through the exhaust line. ### Claim 8 (depends on 6) A method for producing a SiC epitaxial wafer using the film deposition method according to claim 6, wherein the deposit-causing gases are a basic N-based gas composed of molecules which include an N atom within each molecule but have neither a double bond nor a triple bond between N atoms, and a Cl-based gas composed of molecules which include a Cl atom within each molecule.