Solder particles

Patent metadata

Field	Value
Publication number	US-12172240-B2
Application number	US-201917255982-A
Country	US
Kind code	B2
Filing date	Jun 26, 2019
Priority date	Jun 26, 2018
Publication date	Dec 24, 2024
Grant date	Dec 24, 2024

Abstract

The present invention relates to solder particles, each of which partially has a flat portion in the surface. By using these solder particles, electrodes facing each other are able to be appropriately connected, thereby achieving an anisotropic conductive material that exhibits excellent conduction reliability and excellent insulation reliability.

First claim

The invention claimed is:

1. A solder particle having:
a flat portion on a part of a surface; and
a curved portion having a spherical crown shape, on the surface other than the flat portion,
a ratio (A/B) of a diameter A of the flat portion to a diameter B of the solder particle satisfies the following formula:
0.01 <A/B <1.0.

2. The solder particle according to claim 1 , having an average particle diameter of 1 to 30 μm and a C.V. value of 20% or less.

3. The solder particle according to claim 2 ,
wherein a quadrangle circumscribing a projected image of the solder particle is created by two pairs of parallel lines, and distances between opposite sides are set as X and Y, where Y<X, X and Y satisfy the following formula:
0.8 <Y/X <1.0.

4. The solder particle according to claim 3 , comprising at least one selected from the group consisting of tin, tin alloys, indium and indium alloys.

5. The solder particle according to claim 2 , comprising at least one selected from the group consisting of tin, tin alloys, indium and indium alloys.

6. The solder particle according to claim 5 , comprising at least one selected from the group consisting of In—Sn alloys, In—Sn—Ag alloys, In—Bi alloys, Sn—Au alloys, Sn—Bi alloys, Sn—Bi—Ag alloys, Sn—Ag—Cu alloys and Sn—Cu alloys.

7. The solder particle according to claim 1 ,
wherein a quadrangle circumscribing a projected image of the solder particle is created by two pairs of parallel lines, and distances between opposite sides are set as X and Y, where Y<X, X and Y satisfy the following formula:
0.8< Y/X< 1.0.

8. The solder particle according to claim 7 , comprising at least one selected from the group consisting of tin, tin alloys, indium and indium alloys.

9. The solder particle according to claim 8 , comprising at least one selected from the group consisting of In—Sn alloys, In—Sn—Ag alloys, In—Bi alloys, Sn—Au alloys, Sn—Bi alloys, Sn—Bi—Ag alloys, Sn—Ag—Cu alloys and Sn—Cu alloys.

10. The solder particle according to claim 1 , comprising at least one selected from the group consisting of tin, tin alloys, indium and indium alloys.

11. The solder particle according to claim 10 , comprising at least one selected from the group consisting of In—Sn alloys, In—Sn—Ag alloys, In—Bi alloys, Sn—Au alloys, Sn—Bi alloys, Sn—Bi—Ag alloys, Sn—Ag—Cu alloys and Sn—Cu alloys.

Assignees

• Showa Denko Materials Co Ltd
• Resonac Corp

Inventors

• Akai Kunihiko
• Ejiri Yoshinori
• Okada Yuuhei
• Moriya Toshimitsu
• Sukata Shinichirou
• Miyaji Masayuki

Classifications

• B22F1/00

  Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties · CPC title

• B23K35/262

  Sn as the principal constituent · CPC title

• B23K2103/08

  Non-ferrous metals or alloys · CPC title

• H05K3/32

  electrically connecting electric components or wires to printed circuits · CPC title

• H01R11/01

  characterised by the form or arrangement of the conductive interconnection between the connecting locations · CPC title