# US 11,452,204 B2 · Ceramic circuit board, method for manufacturing ceramic circuit board, and module using ceramic circuit board > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,452,204 B2 - Document ID: US11452204B2 - Status: Granted - Kind: B2 - Application number: 16/606,405 - Filed: 2018-04-24 - Published: 2020-04-23 - Granted: 2022-09-20 - Earliest claimed: 2017-04-25 - Assignees: Denka Company Limited - Applicants: Denka Company Limited - Inventors: Yusaku Harada; Akimasa Yuasa; Takahiro Nakamura; Shuhei Morita; Kouji Nishimura - Web page: https://patentgrep.com/patent/US11452204B2 ## CPC - H05K 1/0306: {Inorganic insulating substrates, e.g. ceramic, glass} - C04B 37/026: {consisting of metals or metal salts} - H10W 40/10: Arrangements for heating - H10W 40/255: {having a laminate or multilayered structure, e.g. direct bond copper [DBC] ceramic substrates} - H10W 70/60: Insulating or insulated package substrates; Interposers; Redistribution layers (leadframes H10W70/40) - H10W 90/00: Package configurations - C04B 2235/6562: Heating rate - C04B 2235/6567: Treatment time - C04B 2235/658: Atmosphere during thermal treatment - C04B 2235/77: Density - C04B 2237/124: based on copper - C04B 2237/125: based on noble metals, e.g. silver - C04B 2237/126: wherein the active component for bonding is not the largest fraction of the interlayer - C04B 2237/366: Aluminium nitride - C04B 2237/368: Silicon nitride - C04B 2237/407: Copper - C04B 2237/60: Forming at the joining interface or in the joining layer specific reaction phases or zones, e.g. diffusion of reactive species from the interlayer to the substrate or from a substrate to the joining interface, carbide forming at the joining interface - C04B 2237/708: of one or more of the interlayers - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - C04B: LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE {(roofing granules E04D7/005)}; CERAMICS (devitrified glass-ceramics C03C10/00); REFRACTORIES; TREATMENT OF NATURAL STONE - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract A ceramic circuit substrate and power module with excellent heat cycle resistance characteristics, which is formed by bonding a ceramic substrate and a copper plate via a brazing material including Ag, Cu, and an active metal, wherein the bond void fraction is no greater than 1.0% and the diffusion distance of the Ag, which is a brazing material component, is 5-20 μm. Also, a method for manufacturing a ceramic circuit substrate characterized in that the heating time in a temperature range 400-700° C. in a process for raising the temperature to a bonding temperature is 5-30 minutes and bonding is performed by maintaining the bonding temperature at 720-800° C. for 5-30 minutes. ## Claims ### Claim 1 A ceramic circuit substrate comprising a ceramic substrate bonded with a copper plate via a brazing material comprising Ag, Cu, and an active metal, wherein a bond void fraction is no greater than 1.0%, and a diffusion distance between a surface of the ceramic substrate, which is in contact with the brazing material, and a maximum point at which the Ag diffuses in a copper plate thickness direction from the surface of the ceramic substrate into the copper plate is 5-20 μm. ### Claim 2 (depends on 1) The ceramic circuit substrate according to claim 1, wherein the ceramic substrate comprises silicon nitride or aluminum nitride. ### Claim 3 (depends on 1) The ceramic circuit substrate according to claim 1, wherein the brazing material comprises Sn. ### Claim 4 (depends on 1) A manufacturing method for the ceramic circuit substrate according to claim 1, wherein a heating time in a temperature range 400-700° C. in a process for raising the temperature to a bonding temperature is 5-30 minutes and bonding is performed by maintaining the bonding temperature at 720-800° C. for 5-30 minutes. ### Claim 5 (depends on 4) The manufacturing method for a ceramic circuit substrate according to claim 4, further comprising bonding in a continuous heating furnace in a nitrogen atmosphere. ### Claim 6 (depends on 1) A power module using the ceramic circuit substrate according to claim 1. ### Claim 7 (depends on 2) The ceramic circuit substrate according to claim 2, wherein the brazing material comprises Sn. ### Claim 8 (depends on 2) A manufacturing method for the ceramic circuit substrate according to claim 2, wherein a heating time in a temperature range 400-700° C. in a process for raising the temperature to a bonding temperature is 5-30 minutes and bonding is performed by maintaining the bonding temperature at 720-800° C. for 5-30 minutes. ### Claim 9 (depends on 3) A manufacturing method for the ceramic circuit substrate according to claim 3, wherein the heating time in a temperature range 400-700° C. in a process for raising the temperature to a bonding temperature is 5-30 minutes and bonding is performed by maintaining the bonding temperature at 720-800° C. for 5-30 minutes. ### Claim 10 (depends on 7) A manufacturing method for the ceramic circuit substrate according to claim 7, wherein a heating time in a temperature range 400-700° C. in a process for raising the temperature to a bonding temperature is 5-30 minutes and bonding is performed by maintaining the bonding temperature at 720-800° C. for 5-30 minutes. ### Claim 11 (depends on 8) The manufacturing method for a ceramic circuit substrate according to claim 8, further comprising bonding in a continuous heating furnace in a nitrogen atmosphere. ### Claim 12 (depends on 9) The manufacturing method for a ceramic circuit substrate according to claim 9, further comprising bonding in a continuous heating furnace in a nitrogen atmosphere. ### Claim 13 (depends on 10) The manufacturing method for a ceramic circuit substrate according to claim 10, further comprising bonding in a continuous heating furnace in a nitrogen atmosphere. ### Claim 14 (depends on 2) A power module using the ceramic circuit substrate according to claim 2. ### Claim 15 (depends on 3) A power module using the ceramic circuit substrate according to claim 3. ### Claim 16 (depends on 7) A power module using the ceramic circuit substrate according to claim 7.