Cu ball

Patent metadata

Field	Value
Publication number	US-9668358-B2
Application number	US-201214649439-A
Country	US
Kind code	B2
Filing date	Dec 6, 2012
Priority date	Dec 6, 2012
Publication date	May 30, 2017
Grant date	May 30, 2017

Abstract

A Cu ball that has low α dose and high sphericity even when containing at least a certain amount of impurity elements other than Cu. Even when the purity thereof is 99.995% or less and U and Th contents are 5 ppb or less in order to suppress any software errors and decrease connection failure, α dose is 0.0200 cph/cm 2 or less. Further, the sphericity of the Cu ball is unexpectedly improved by making the purity not more than 99.995%.

First claim

The invention claimed is:

1. A Cu ball characterized in that the Cu ball contains a Pb content of 1 ppm or more, and has a sphericity of 0.95 or more, a purity from 99.9% or more to 99.995% or less, an α dose of 0.0200 cph/cm 2 or less, a U content of 5 ppb or less, a Th content of 5 ppb or less, and a diameter in the range of 1 μm through 1000 μm.

2. The Cu ball according to claim 1 wherein the α dose is 0.0020 cph/cm2 or less.

3. The Cu ball according to claim 1 wherein the α dose is 0.0010 cph/cm2 or less.

4. A Cu core ball including:
the Cu ball according to claim 1 , and
solder plating which covers the Cu ball.

5. A Cu core ball including:
the Cu ball according to claim 2 , and
solder plating which covers the Cu ball.

6. A Cu core ball including:
the Cu ball according to claim 1 ,
Ni plating which covers the Cu ball; and
solder plating which covers the Ni plating.

7. A Cu core ball including:
the Cu ball according to claim 2 ,
Ni plating which covers the Cu ball; and
solder plating which covers the Ni plating.

8. A solder joint using, the Cu ball according to claim 1 .

9. A solder joint using the Cu ball according to claim 2 .

10. A solder joint using the Cu core ball according to claim 4 .

11. A solder joint using the Cu core ball according to claim 5 .

12. A solder joint using the Cu core ball according to claim 6 .

13. A solder joint using the Cu core ball according to claim 7 .

Assignees

• Senju Metal Industry Co

Inventors

• Kawasaki Hiroyoshi
• Hattori Takahiro
• Roppongi Takahiro
• Soma Daisuke
• Sato Isamu

Classifications

• H10W90/701

  characterised by the relative positions of pads or connectors relative to package parts · CPC title

• H10W72/20

  Bump connectors, e.g. solder bumps or copper pillars; Dummy bumps; Thermal bumps · CPC title

• H05K3/346

  Solder materials or compositions specially adapted therefor · CPC title

• B22F1/065 Primary

  Spherical particles · CPC title

• C22F1/08

  of copper or alloys based thereon · CPC title