Core material, semiconductor package, and forming method of bump electrode

Patent metadata

Field	Value
Publication number	US-10381319-B2
Application number	US-201715832905-A
Country	US
Kind code	B2
Filing date	Dec 6, 2017
Priority date	Dec 7, 2016
Publication date	Aug 13, 2019
Grant date	Aug 13, 2019

Abstract

A core material including a core and a solder plating layer of a (Sn—Bi)-based solder alloy made of Sn and Bi on a surface of the core. Bi in the solder plating layer is distributed in the solder plating layer at a concentration ratio in a predetermined range of, for example, 91.7% to 106.7%. Bi in the solder plating layer is homogeneous, and thus, a Bi concentration ratio is in a predetermined range over the entire solder plating layer including an inner circumference side and an outer circumference side in the solder plating layer.

First claim

What is claimed is:

1. A core material, comprising:
a core; and
an electric solder plating layer of an (Sn—Bi)-based solder alloy made of Sn and Bi in an amount of a target content having a value in a range of 3 to 58 mass % on a surface of the core, wherein
the core includes a metal simple substance of Cu, Ni, Ag, Bi, Pb, Al, Sn, Fe, Zn, In, Ge, Sb, Co, Mn, Au, Si, Pt, Cr, La, Mo, Nb, Pd, Ti, Zr, or Mg, or an alloy of two or more thereof, a metal oxide thereof, or a metal mixed oxide thereof, and
when a concentration ratio of Bi contained in the solder plating layer is set to
Concentration Ratio (%)=(Measured Value of Bi (mass %)/Target Bi Content (mass %))*100, or
Concentration Ratio (%)=(Average Value of Measured Values of Bi (mass %)/Target Bi Content (mass %))*100,

the concentration ratio is in a range of 91.4% to 106.7% across the entire electric solder plating layer.

2. The core material according to claim 1 , wherein the core material further includes a base plating layer of one or more elements selected from the group of Ni and Co, between the surface of the core and the electric solder plating layer in this order.

3. The core material according to claim 2 , wherein a Cu ball or a Cu column is used as the core.

4. The core material according to claim 1 , wherein a Cu ball or a Cu column is used as the core.

5. A semiconductor package in which the core material according to claim 1 is used as a solder bump.

6. A core material, comprising:
a core; and
an electric solder plating layer of an (Sn-58Bi)-based solder alloy made of Sn and Bi in an amount of a target content of 58 mass % on a surface of the core, wherein
the core includes a metal simple substance of Cu, Ni, Ag, Bi, Pb, Al, Sn, Fe, Zn, In, Ge, Sb, Co, Mn, Au, Si, Pt, Cr, La, Mo, Nb, Pd, Ti, Zr, or Mg, or an alloy of two or more thereof, a metal oxide thereof, or a metal mixed oxide thereof, and
when a concentration ratio of Bi contained in the solder plating layer is set to
Concentration Ratio (%)=(Measured Value of Bi (mass %)/Target Bi Content (mass %))*100, or
Concentration Ratio (%)=(Average Value of Measured Values of Bi (mass %)/Target Bi Content (mass %))*100,

the concentration ratio is in a range of 91.4% to 108.6% across the entire electric solder plating layer.

7. The core material according to claim 6 , wherein the core material further includes a base plating layer of one or more elements selected from the group of Ni and Co, between the surface of the core and the electric solder plating layer in this order.

8. The core material according to claim 7 , wherein a Cu ball or a Cu column is used as the core.

9. The core material according to claim 6 , wherein a Cu ball or a Cu column is used as the core.

10. A semiconductor package in which the core material according to claim 6 is used as a solder bump.

11. A core material, comprising:
a core; and
an electric solder plating layer of an (Sn-40Bi)-based solder alloy made of Sn and Bi in an amount of a target content of 40 mass % on a surface of the core, wherein
the core includes a metal simple substance of Cu, Ni, Ag, Bi, Pb, Al, Sn, Fe, Zn, In, Ge, Sb, Co, Mn, Au, Si, Pt, Cr, La, Mo, Nb, Pd, Ti, Zr, or Mg, or an alloy of two or more thereof, a metal oxide thereof, or a metal mixed oxide thereof, and
when a concentration ratio of Bi contained in the solder plating layer is set to
Concentration Ratio (%)=(Measured Value of Bi (mass %)/Target Bi Content (mass %))*100, or
Concentration Ratio (%)=(Average Value of Measured Values of Bi (mass %)/Target Bi Content (mass %))*100,

the concentration ratio is in a range of 90% to 107.5% across the entire electric solder plating layer.

12. The core material according to claim 11 , wherein the core material further includes a base plating layer of one or more elements selected from the group of Ni and Co, between the surface of the core and the electric solder plating layer in this order.

13. The core material according to claim 12 , wherein a Cu ball or a Cu column is used as the core.

14. The core material according to claim 11 , wherein a Cu ball or a Cu column is used as the core.

15. A semiconductor package in which the core material according to claim 11 is used as a solder bump.

16. A core material, comprising:
a core; and
an electric solder plating layer of an (Sn-3Bi)-based solder alloy formed of Sn and Bi in an amount of a target content of 3 mass % on a surface of the core, wherein
the core includes a metal simple substance of Cu, Ni, Ag, Bi, Pb, Al, Sn, Fe, Zn, In, Ge, Sb, Co, Mn, Au, Si, Pt, Cr, La, Mo, Nb, Pd, Ti, Zr, or Mg, or an alloy of two or more thereof, a metal oxide thereof, or a metal mixed oxide thereof, and
when a concentration ratio of Bi contained in the solder plating layer is set to
Concentration Ratio (%)=(Measured Value of Bi (mass %)/Target Bi Content (mass %))*100, or
Concentration Ratio (%)=(Average Value of Measured Values of Bi (mass %)/Target Bi Content (mass %))*100,

the concentration ratio is in a range of 90% to 106.7% across the entire electric solder plating layer.

17. The core material according to claim 16 , wherein the core material further includes a base plating layer of one or more elements selected from the group of Ni and Co, between the surface of the core and the electric solder plating layer in this order.

18. The core material according to claim 17 , wherein a Cu ball or a Cu column is used as the core.

19. The core material according to claim 16 , wherein a Cu ball or a Cu column is used as the core.

20. A semiconductor package in which the core material according to claim 16 is used as a solder bump.

Assignees

• Senju Metal Industry Co

Inventors

• Nishino Tomoaki
• Kondo Shigeki
• Hattori Takahiro
• Kawasaki Hiroyoshi
• Roppongi Takahiro
• Soma Daisuke
• Sato Isamu

Classifications

• H10W72/01257

  by reflowing · CPC title

• H10W72/01235

  by plating, e.g. electroless plating or electroplating · CPC title

• H10W72/255

  of outermost layers of multilayered bumps, e.g. material of a coating · CPC title

• H10W72/252

  comprising solid metals or solid metalloids, e.g. PbSn, Ag or Cu · CPC title

• H10W72/245

  of outermost layers of multilayered bumps, e.g. bump coating being only on a part of a bump core · CPC title