# US 12,000,019 B2 · Gold powder, production method for gold powder, and gold paste > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,019 B2 - Document ID: US12000019B2 - Status: Granted - Kind: B2 - Application number: 17/632,221 - Filed: 2020-07-20 - Published: 2022-07-14 - Granted: 2024-06-04 - Earliest claimed: 2019-08-05 - Assignees: Tanaka Kikinzoku Kogyo K.K. - Applicants: Tanaka Kikinzoku Kogyo K.K. - Inventors: Toshinori Ogashiwa; Masayuki Miyairi - Web page: https://patentgrep.com/patent/US12000019B2 ## CPC - B22F 9/18: with reduction of metal compounds - B22F 1/00: Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties - B22F 1/05: Metallic powder characterised by the size or surface area of the particles - B22F 1/0545: Dispersions or suspensions of nanosized particles - B22F 1/10: Metallic powder containing lubricating or binding agents; Metallic powder containing organic material - B22F 1/145: Chemical treatment, e.g. passivation or decarburisation - B22F 3/10: Sintering only - B22F 3/14: simultaneously - B22F 7/064: {using an intermediate powder layer} - B22F 9/24: starting from liquid metal compounds, e.g. solutions - B23K 35/3013: {Au as the principal constituent} - B29C 65/02: by heating, with or without pressure - H01B 1/02: mainly consisting of metals or alloys - H01B 1/22: the conductive material comprising metals or alloys - B22F 2301/255: Silver or gold - H10W 72/20: Bump connectors, e.g. solder bumps or copper pillars; Dummy bumps; Thermal bumps - H10W 72/30: Die-attach connectors - H10W 72/325: {Die-attach connectors having a filler embedded in a matrix} - H10W 72/352: {comprising metals or metalloids, e.g. solders} - H10W 72/90: Bond pads, in general - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A gold powder comprising gold having a purity of 99.9% by mass or more and having an average particle size of 0.01 μm or more and 1.0 μm or less, a content of a chloride ion is 100 ppm or less, and a content of a cyanide ion is 10 ppm or more and 1000 ppm or less. A total of the content of a chloride ion and the content of a cyanide ion is preferably 110 ppm or more and 1000 ppm or less. The gold powder has improved adaptability to various processes including bonding or the like with a content of a chloride ion, that is, an impurity, optimized. A gold paste using this gold powder is suitably used in various uses for bonding such as die bonding of a semiconductor chip, sealing a semiconductor package, and forming an electrode/wire. ## Claims ### Claim 1 A gold powder comprising gold having a purity of 99.9% by mass or more and having an average particle size of 0.01 μm or more and 1.0 μm or less, wherein a content of a chloride ion in the gold powder is 10 ppm or more and 100 ppm or less, a content of a cyanide ion in the gold powder is 10 ppm or more and 1000 ppm or less, and a combined content of the chloride ion and the cyanide ion in the gold powder is 110 ppm or more and 1000 ppm or less. ### Claim 2 (depends on 1) The gold powder according to claim 1, wherein the content of the cyanide ion is 100 ppm or more and 1000 ppm or less. ### Claim 3 (depends on 1) A gold paste, comprising the gold powder defined in claim 1, and an organic solvent. ### Claim 4 (depends on 2) A gold paste, comprising the gold powder defined in claim 2, and an organic solvent. ### Claim 5 (depends on 1) A production method for the gold powder defined in claim 1, comprising: a step of producing, by a wet reduction method, a gold powder comprising gold having a purity of 99.9% by mass or more and having an average particle size of 0.01 μm or more and 1.0 μm or less; and a step of reducing the content of a chloride ion by contacting the gold powder with a cyanide solution. ### Claim 6 (depends on 5) The production method for the gold powder according to claim 5, wherein a cyanide ion concentration in the cyanide solution is 0.01% by mass or more and 5% by mass or less. ### Claim 7 (depends on 2) A production method for the gold powder defined in claim 2, comprising: a step of producing, by a wet reduction method, a gold powder comprising gold having a purity of 99.9% by mass or more and having an average particle size of 0.01 μm or more and 1.0 μm or less; and a step of reducing the content of a chloride ion by contacting the gold powder with a cyanide solution. ### Claim 8 (depends on 1) A method for bonding a pair of bonding members to each other, comprising: (a) a step of applying, to one bonding member, a gold paste comprising the gold powder defined in claim 1 and an organic solvent; and (b) a step of overlapping the one bonding member and another bonding member on each other via the applied gold paste, and heating at least the gold paste at a temperature of 80° C. or more and 300° C. or less for bonding the pair of bonding members to each other. ### Claim 9 (depends on 8) The bonding method according to claim 8, comprising overlapping the one bonding member and the other bonding member on each other, and subsequently applying a pressure for bonding to the pair of bonding members in one or more directions under heating. ### Claim 10 (depends on 1) A method for bonding a pair of bonding members to each other, comprising: (a) a step of applying, to one bonding member, a gold paste comprising the gold powder defined in claim 1, and an organic solvent; (b) a step of sintering the gold paste at a temperature of 80 to 300° C. to obtain a metal powder sintered body; and (c) a step of overlapping the one bonding member on another bonding member via the formed metal powder sintered body, and heating at least the metal powder sintered body and applying a pressure in one or more directions for bonding. ### Claim 11 (depends on 1) A method for bonding a base material holding a content thereon to a lid body for the base material, comprising: (a) a step of applying, to the base material or the lid body, a gold paste comprising the gold powder defined in claim 1 and an organic solvent; (b) a step of sintering the gold paste at a temperature of 80 to 300° C. to obtain a metal powder sintered body; and (c) a step of overlapping the base material on the lid body via the metal powder sintered body, and bonding the base material and the lid body to each other by applying a pressure in one or more directions under heating at least the metal powder sintered body. ### Claim 12 (depends on 1) An electrode or wire forming method for forming an electrode or a wire on a substrate, comprising: (a) a step of applying, to the substrate, a gold paste comprising the gold powder according to the claim 1, and an organic solvent; and (b) a step of sintering the gold paste at a temperature of 80 to 300° C. to form an electrode or a wire containing a metal powder sintered body. ### Claim 13 (depends on 2) A method for bonding a pair of bonding members to each other, comprising: (a) a step of applying, to one bonding member, a gold paste comprising the gold powder defined in claim 2 and an organic solvent; and (b) a step of overlapping the one bonding member and another bonding member on each other via the applied gold paste, and heating at least the gold paste at a temperature of 80° C. or more and 300° C. or less for bonding the pair of bonding members to each other. ### Claim 14 (depends on 2) A method for bonding a pair of bonding members to each other, comprising: (a) a step of applying, to one bonding member, a gold paste comprising the gold powder defined in claim 2, and an organic solvent; (b) a step of sintering the gold paste at a temperature of 80 to 300° C. to obtain a metal powder sintered body; and (c) a step of overlapping the one bonding member on another bonding member via the formed metal powder sintered body, and heating at least the metal powder sintered body and applying a pressure in one or more directions for bonding.