Joining method, joint structure, electronic device, method for manufacturing electronic device and electronic part

Patent metadata

Field	Value
Publication number	US-9614295-B2
Application number	US-201514918648-A
Country	US
Kind code	B2
Filing date	Oct 21, 2015
Priority date	Dec 24, 2010
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

A joint structure that includes a first metal member, a second metal member, and a joint portion sandwiched between the first metal member and the second metal member. At least a Cu-M-Sn intermetallic compound is dispersed in the joint portion, M is at least one of Ni and Mn, and neither a Cu 3 Sn layer nor a Cu 6 Sn 5 layer is present on at least one of interfaces between the joint portion and the first metal member and the second metal member.

First claim

The invention claimed is:

1. A joint structure comprising:
a first metal member;
a second metal member; and
a joint portion sandwiched between the first metal member and the second metal member,
wherein at least a Cu-M-Sn intermetallic compound is dispersed in the joint portion, M is at least one of Ni and Mn, and neither a Cu 3 Sn layer nor a Cu 6 Sn 5 layer is present on a first interface between the joint portion and the first metal member and a second interface between the joint portion and the second metal member, and a material of at least one of the first metal member and the second metal member is a Cu—Mn or a Cu—Ni alloy.

2. An electronic device in which the first metal member having at least a surface of a first metal is joined to the second metal member having at least a surface of a second metal with the joint portion sandwiched therebetween, wherein the joint portion has the joint structure according to claim 1 .

3. An electronic part comprising:
a first electrode;
a second electrode; and
a joining material in contact with a first surface of the first electrode and a second surface of the second electrode, the joining material including a joining metal of Sn or an alloy containing Sn in an amount of 70% by weight or more,
wherein the first surface of the first electrode in contact with the joining material is a Cu—Mn alloy or a Cu—Ni alloy which forms an intermetallic compound with the joining metal, and has a lattice constant difference of 50% or more from the intermetallic compound, and
neither a Cu 3 Sn layer nor a Cu 6 Sn 5 layer is present on a first interface between the joining material and the first electrode and a second interface between the joining material and the second electrode.

4. The electronic part according to claim 3 , wherein the first surface of the first electrode in contact with the joining material is a Cu—Mn alloy containing Mn in a proportion of 5 to 30% by weight or a Cu—Ni alloy containing Ni in a proportion of 5 to 30% by weight.

5. The electronic part according to claim 3 , wherein the first surface of the first electrode in contact with the joining material is a Cu—Mn alloy containing Mn in a proportion of 10 to 15% by weight or a Cu—Ni alloy containing Ni in a proportion of 10 to 15% by weight.

Assignees

• Murata Manufacturing Co

Inventors

• Nakano Kosuke
• Takaoka Hidekiyo

Classifications

• H05K3/346

  Solder materials or compositions specially adapted therefor · CPC title

• B23K35/0238 Primary

  layered · CPC title

• H01R4/02 Primary

  Soldered or welded connections {(H01R4/625, H01R4/723, H01R12/59 take precedence)} · CPC title

• C22C9/05

  with manganese as the next major constituent · CPC title

• C22C9/06

  with nickel or cobalt as the next major constituent · CPC title