# US 10,375,825 B2 · Power module substrate, power module substrate with heat sink, power module, method of manufacturing power module substrate, and copper member-bonding paste > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,375,825 B2 - Document ID: US10375825B2 - Status: Granted - Kind: B2 - Application number: 15/289,453 - Filed: 2016-10-10 - Published: 2017-02-02 - Granted: 2019-08-06 - Earliest claimed: 2012-02-01 - Assignees: Mitsubishi Materials Corporation - Applicants: Mitsubishi Materials Corporation - Inventors: Nobuyuki Terasaki; Yoshiyuki Nagatomo; Kimihito Nishikawa; Yoshirou Kuromitsu - Web page: https://patentgrep.com/patent/US10375825B2 ## CPC - H05K 1/0271: {Arrangements for reducing stress or warp in rigid printed circuit boards, e.g. caused by loads, vibrations or differences in thermal expansion} - B23K 1/0008: {specially adapted for particular articles or work} - B23K 1/0016: {Soldering of electronic components} - B23K 35/025: {Pastes, creams or slurries} - B23K 35/262: {Sn as the principal constituent} - B23K 35/30: with the principal constituent melting at less than 1550°C - B23K 35/3006: {Ag as the principal constituent} - B23K 35/32: with the principal constituent melting at more than 1550°C - B23K 35/36: Selection of non-metallic compositions, e.g. coatings or fluxes (B23K35/34 takes precedence); Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest - B23K 35/365: Selection of non-metallic compositions of coating materials either alone or conjoint with selection of soldering or welding materials - C04B 35/632: Organic additives - C04B 37/025: {consisting of glass or ceramic material} - C04B 37/026: {consisting of metals or metal salts} - C22C 5/06: Alloys based on silver - C22C 14/00: Alloys based on titanium - C22C 16/00: Alloys based on zirconium - C22C 21/00: Alloys based on aluminium - C22C 27/00: Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00 - C22C 27/02: Alloys based on vanadium, niobium, or tantalum - C22C 28/00: Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00 - C22C 30/04: containing tin or lead - C22F 1/08: of copper or alloys based thereon - G01B 15/02: for measuring thickness - G01N 23/203: Measuring back scattering - H05K 1/0203: {Cooling of mounted components (H05K1/0272 takes precedence)} - H05K 1/0306: {Inorganic insulating substrates, e.g. ceramic, glass} - H05K 1/09: Use of materials for the {conductive, e.g. } metallic pattern - H05K 1/18: structurally associated with non-printed electric components (H05K1/16 takes precedence) - H05K 1/181: associated with surface mounted components - H05K 3/388: {by the use of a metallic or inorganic thin film adhesion layer} - H05K 13/0465: {by soldering (H05K13/0469 takes precedence)} - H10W 40/255: {having a laminate or multilayered structure, e.g. direct bond copper [DBC] ceramic substrates} - B23K 2101/42: Printed circuits - C04B 2235/44: Metal salt constituents or additives chosen for the nature of the anions, e.g. hydrides or acetylacetonate - C04B 2237/08: Non-oxidic interlayers - C04B 2237/121: based on aluminium - C04B 2237/122: based on refractory metals - 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 2237/127: The active component for bonding being a refractory metal - C04B 2237/128: The active component for bonding being silicon - C04B 2237/366: Aluminium nitride - C04B 2237/368: Silicon nitride - C04B 2237/402: Aluminium - 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 2237/704: of one or more of the ceramic layers or articles - C04B 2237/706: of one or more of the metallic layers or articles - C04B 2237/708: of one or more of the interlayers - C04B 2237/72: Forming laminates or joined articles comprising at least two interlayers directly next to each other - G01N 2223/633: thickness, density, surface weight (unit area) - H05K 2201/0175: Inorganic, non-metallic layer, e.g. resist or dielectric for printed capacitor - H10W 90/734: {between a chip and a stacked insulating package substrate, interposer or RDL} - Y10T 428/12542: More than one such component - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - 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 - 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 - C22C: ALLOYS (treatment of alloys C21D, C22F) - C22F: CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS (surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by this subclass, C23F17/00) - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract This power module substrate includes a copper plate that is formed of copper or a copper alloy and is laminated on a surface of a ceramic substrate 11; a nitride layer 31 that is formed on the surface of the ceramic substrate 11 between the copper plate and the ceramic substrate 11; and an Ag—Cu eutectic structure layer 32 having a thickness of 15 μm or less that is formed between the nitride layer and the copper plate. ## Claims ### Claim 1 A power module substrate, comprising: a ceramic substrate that is formed of AlN or Si3N4 and has a first surface; a copper plate that is formed of copper or a copper alloy and is laminated and bonded on the first surface of the ceramic substrate; a nitride layer that contains at least one nitride of elements selected from Ti, Hf, Zr, and Nb, is formed on the first surface of the ceramic substrate between the copper plate and the ceramic substrate and the nitride layer contains one or two or more additional elements selected from In, Al, Mn and Zn; and an Ag—Cu eutectic structure layer that has a thickness of 15 μm or less and is formed between the nitride layer and the copper plate, wherein the thickness of the Ag—Cu eutectic structure layer is measured by a method comprising: obtaining a backscattered electron image of an interface between the copper plate and the ceramic substrate using an EPMA; based on the backscattered electron image, measuring the area of the Ag—Cu eutectic structure layer continuously formed on the bonding interface in a measurement visual field at a magnification of 2000 times; dividing the area of the Ag—Cu eutectic structure layer by the width of the measurement visual field, and obtaining the average of the thicknesses in five measurement visual fields as the thickness of the Ag—Cu eutectic structure layer. ### Claim 2 (depends on 1) The power module substrate according to claim 1, wherein the ceramic substrate is formed of AlN, and the thickness of the Ag—Cu eutectic structure layer is 14 μm or less. ### Claim 3 (depends on 1) The power module substrate according to claim 1, wherein the ceramic substrate is formed of Si3N4, and the thickness of the Ag—Cu eutectic structure layer is 1 μm or less. ### Claim 4 (depends on 1) A power module substrate according to claim 1, wherein the power module substrate has no crack after repeating cooling-heating cycles of −45° C. to 125° C. for 3500 times on the power module substrate. ### Claim 5 (depends on 1) A power module substrate with a heat sink, comprising: the power module substrate according to claim 1; and a heat sink that cools the power module substrate. ### Claim 6 (depends on 1) A power module, comprising: the power module substrate according to claim 1; and an electronic component that is mounted on the power module substrate. ### Claim 7 A power module substrate, comprising: a ceramic substrate that is formed of AlN or Si3N4 and has a first surface; a copper plate that is formed of copper or a copper alloy and is laminated and bonded on the first surface of the ceramic substrate; a nitride layer that contains a nitride of Nb and is formed on the first surface of the ceramic substrate between the copper plate and the ceramic substrate; and an Ag—Cu eutectic structure layer that has a thickness of 15 μm or less and is formed between the nitride layer and the copper plate, wherein the thickness of the Ag—Cu eutectic structure layer is measured by a method comprising: obtaining a backscattered electron image of an interface between the copper plate and the ceramic substrate using an EPMA; based on the backscattered electron image, measuring the area of the Ag—Cu eutectic structure layer continuously formed on the bonding interface in a measurement visual field at a magnification of 2000 times; dividing the area of the Ag—Cu eutectic structure layer by the width of the measurement visual field, and obtaining the average of the thicknesses in five measurement visual fields as the thickness of the Ag—Cu eutectic structure layer.