Ceramic circuit board, manufacturing method for ceramic circuit board, and brazing material for circuit formation

Patent metadata

Field	Value
Publication number	US-2026068042-A1
Application number	US-202519287388-A
Country	US
Kind code	A1
Filing date	Jul 31, 2025
Priority date	Sep 2, 2024
Publication date	Mar 5, 2026
Grant date	—

Abstract

A low-cost ceramic circuit board that offers enhanced design flexibility in circuit layer thickness by increasing the bonding strength between a circuit layer and a ceramic substrate. A ceramic circuit board includes a ceramic substrate and a metal circuit layer formed on the ceramic substrate. The metal circuit layer contains Cu, Mg, at least one element selected from the group including Sn, Sb, and Bi, and at least one active metal element selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

First claim

1 . A ceramic circuit board comprising:
a ceramic substrate; and a metal circuit layer formed on the ceramic substrate, wherein the metal circuit layer contains Cu, Mg, at least one element selected from the group consisting of Sn, Sb, and Bi, and at least one active metal element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

2 . The ceramic circuit board according to claim 1 , wherein Cu is the element having the highest content among the elements contained in the metal circuit layer.

3 . The ceramic circuit board according to claim 1 , wherein in the metal circuit layer, the Cu content is 40 to 85 at %, the Mg content is 0.2 to 25 at %, and the total content of Sn, Sb, and Bi is 1 to 25 at %.

4 . The ceramic circuit board according to claim 1 , wherein an interfacial reaction layer containing at least one from among a compound of the active metal element and MgO is present between the ceramic substrate and the metal circuit layer.

5 . The ceramic circuit board according to claim 1 , wherein the metal circuit layer further contains at least one element selected from the group consisting of Ag, In, and Mn.

6 . The ceramic circuit board according to claim 1 , wherein the metal circuit layer includes: a solid solution phase in which a metal element other than Cu is dissolved in Cu; and a compound phase having at least one intermetallic compound selected from the group consisting of Cu 4 MgSn, CuMgSb, and CuMgBi.

7 . The ceramic circuit board according to claim 1 , wherein the thickness of the metal circuit layer is 5 μm or more and 300 μm or less.

8 . The ceramic circuit board according to claim 1 , wherein
the ceramic substrate has a through-hole, and a metal similar to the metal forming the metal circuit layer is filled in the through-hole.

9 . A method for manufacturing a ceramic circuit board, the method comprising:
placing a brazing material for circuit formation on a ceramic substrate in such a manner that the brazing material for circuit formation corresponds to a circuit pattern, the brazing material for circuit formation containing Cu Mg, at least one first element selected from the group consisting of Sn, Sb, and Bi, and at least one active metal element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W; and heating and holding the ceramic substrate on which the brazing material for circuit formation has been placed.

10 . The method for manufacturing a ceramic circuit board according to claim 9 , wherein Cu is the element having the highest content among the elements contained in the brazing material for circuit formation.

11 . The method for manufacturing a ceramic circuit board according to claim 9 , wherein in the step of placing the brazing material for circuit formation, the brazing material for circuit formation contains 40 to 85 at % of Cu, 1 to 25 at % of Mg, a total of 1 to 25 at % of the first element, and a total of 0.1 to 10 at % of the active metal element.

12 . The method for manufacturing a ceramic circuit board according to claim 11 , wherein in the step of placing the brazing material for circuit formation, the brazing material for circuit formation further contains a second element being at least one selected from the group consisting of Ag, In, and Mn.

13 . The method for manufacturing a ceramic circuit board according to claim 9 , wherein
in the step of placing the brazing material for circuit formation, provided that the content of Mg is X at % and the content of the first element is Y at %, the brazing material for circuit formation satisfies a relationship X−5≤Y≤X+5.

14 . The method for manufacturing a ceramic circuit board according to claim 9 , wherein in the step of placing the brazing material for circuit formation, the brazing material for circuit formation is configured as a paste and contains Cu powder including Cu, and alloy powder formed from an intermetallic compound containing at least Mg, the first element, and the active metal element.

15 . The method for manufacturing a ceramic circuit board according to claim 9 , wherein
in the step of heating and holding of the ceramic substrate, the heating is performed at a temperature of 600° C. or more and 950° C. or less.

16 . A brazing material for circuit formation comprising:
Cu; Mg; at least one first element selected from the group consisting of Sn, Sb, and Bi; and at least one active metal element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.

17 . The brazing material for circuit formation according to claim 16 , wherein Cu is the element having the highest content among the elements contained in the brazing material for circuit formation.

18 . The brazing material for circuit formation according to claim 16 , wherein the brazing material for circuit formation contains 40 to 85 at % of Cu, 1 to 25 at % of Mg, a total of 1 to 25 at % of the first element, and a total of 0.1 to 10 at % of the active metal element.

19 . The brazing material for circuit formation according to claim 18 , wherein the brazing material for circuit formation further contains a second element being at least one selected from the group consisting of Ag, In, and Mn.

Assignees

• Proterial Ltd

Inventors

• Takano shun
• Nogawa Takashi

Classifications

• H05K1/09

  Use of materials for the {conductive, e.g. } metallic pattern · CPC title

• H05K2201/0215

  Metallic fillers · CPC title

• H05K2201/0266

  Size distribution · CPC title

• H05K1/0306 Primary

  Inorganic insulating substrates, e.g. ceramic, glass · CPC title

• H05K3/1291

  Firing or sintering at relative high temperatures for patterns on inorganic boards, e.g. co-firing of circuits on green ceramic sheets · CPC title