Bonding wire for semiconductor device

Patent metadata

Field	Value
Publication number	US-10032741-B2
Application number	US-201515107417-A
Country	US
Kind code	B2
Filing date	Jun 5, 2015
Priority date	Feb 26, 2015
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

The bonding wire for a semiconductor device includes a Cu alloy core material and a Pd coating layer formed on a surface of the Cu alloy core material, and the bonding wire contains In of 0.011 to 1.2% by mass and has the Pd coating layer of a thickness of 0.015 to 0.150 μm. With this configuration, it is able to increase the bonding longevity of a ball bonded part in a high-temperature and high-humidity environment, and thus to improve the bonding reliability. When the Cu alloy core material contains one or more elements of Pt, Pd, Rh and Ni in an amount, for each element, of 0.05 to 1.2% by mass, it is able to increase the reliability of a ball bonded part in a high-temperature environment of 175° C. or more. When an Au skin layer is further formed on a surface of the Pd coating layer, wedge bondability improves.

First claim

The invention claimed is:

1. A bonding wire for a semiconductor device comprising:
a Cu alloy core material; and
a Pd coating layer formed on a surface of the Cu alloy core material, wherein
the bonding wire contains In,
a concentration of In is 0.031% by mass or more and 1.2% by mass or less relative to the entire wire, and
a thickness of the Pd coating layer is 0.015 μm or more and 0.150 μm or less.

2. The bonding wire for a semiconductor device according to claim 1 , wherein
the Cu alloy core material contains at least one element selected from Pt, Pd, Rh and Ni, and
a concentration of each of the elements contained in the Cu alloy core material is 0.05% by mass or more and 1.2% by mass or less.

3. The bonding wire for a semiconductor device according to claim 1 , further comprising an Au skin layer on the Pd coating layer.

4. The bonding wire for a semiconductor device according to claim 3 , wherein a thickness of the Au skin layer is 0.0005 μm or more and 0.050 μm or less.

5. The bonding wire for a semiconductor device according to claim 1 , wherein
the bonding wire further contains at least one element selected from B, P, Mg, Ga and Ge, and
a concentration of each of the elements is 1 ppm by mass or more and 100 ppm by mass or less relative to the entire wire.

6. The bonding wire for a semiconductor device according to claim 1 , wherein, in a measurement result when measuring crystal orientations on a surface of the bonding wire, a crystal orientation <111> angled at 15 degrees or less to a longitudinal direction of the bonding wire has a proportion of 30% or more and 100% or less among crystal orientations in the wire longitudinal direction.

7. The bonding wire for a semiconductor device according to claim 1 , wherein a concentration of In is 0.1% by mass or more and 1.2% by mass or less relative to the entire wire.

8. A bonding wire for ball bonding, comprising:
a Cu alloy core material; and
a Pd coating layer formed on a surface of the Cu alloy core material, wherein
the bonding wire contains In,
a concentration of In is 0.031% by mass or more and 1.2% by mass or less relative to the entire wire,
a thickness of the Pd coating layer is 0.015 μm or more and 0.150 μm or less, and
a ball to be formed when the ball bonding is performed comprises an alloy containing Pd, Cu and In.

Assignees

• Nippon Micrometal Corp
• Nippon Steel & Sumikin Mat Co

Inventors

• Oda Daizo
• Eto Motoki
• Yamada Takashi
• Haibara Teruo
• Oishi Ryo
• Uno Tomohiro
• Oyamada Tetsuya

Classifications

• H10W72/01515

  Forming coatings · CPC title

• H10W72/50

  Bond wires · CPC title

• H10W72/522

  Multilayered bond wires, e.g. having a coating concentric around a core · CPC title

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title

• H10W90/756

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title