	US 12,463,171 B2
	Copper bonding wire for semiconductor devices and semiconductor device
Ryo Oishi, Saitama (JP); Daizo Oda, Saitama (JP); Noritoshi Araki, Saitama (JP); Kota Shimomura, Saitama (JP); Tomohiro Uno, Tokyo (JP); and Tetsuya Oyamada, Tokyo (JP)
Assigned to NIPPON MICROMETAL CORPORATION, Saitama (JP); and NIPPON STEEL Chemical & Material Co., Ltd., Tokyo (JP)
Appl. No. 17/781,316
Filed by NIPPON MICROMETAL CORPORATION, Saitama (JP); and NIPPON STEEL Chemical & Material Co., Ltd., Tokyo (JP)
PCT Filed Nov. 20, 2020, PCT No. PCT/JP2020/043446 § 371(c)(1), (2) Date May 31, 2022, PCT Pub. No. WO2021/111908, PCT Pub. Date Jun. 10, 2021.
Claims priority of application No. 2019-218023 (JP), filed on Dec. 2, 2019.
Prior Publication US 2023/0013769 A1, Jan. 19, 2023
Int. Cl. H01L 23/00 (2006.01); C22F 1/08 (2006.01)

CPC H01L 24/45 (2013.01) [H01L 2224/45147 (2013.01); H01L 2924/01203 (2013.01); H01L 2924/20751 (2013.01); H01L 2924/20752 (2013.01); H01L 2924/20753 (2013.01); H01L 2924/20754 (2013.01); H01L 2924/20755 (2013.01); H01L 2924/20756 (2013.01); H01L 2924/20757 (2013.01); H01L 2924/20758 (2013.01); H01L 2924/20759 (2013.01); H01L 2924/2076 (2013.01)]

5 Claims

1. A copper bonding wire for semiconductor devices, wherein a density of crystal grain boundary on a surface of the wire is 0.6 (μm/μm²) or more and 1.6 (μm/μm²) or less,

wherein the density of crystal grain boundary refers to a total length (μm) of a crystal grain boundary that is present per unit area (μm²),

wherein the density of crystal grain boundary on the surface of the wire is calculated by dividing the total length (μm) of the crystal grain boundary by a measurement area (μm²), where the crystal grain boundary is defined as a boundary at which an orientation difference between adjacent measurement points is 15° or more when measuring by using an EBSD method at measurement point intervals of 0.06 μm or more and 0.6 μm or less, and

wherein the density of crystal grain boundary on the surface of the wire is measured under the condition that a center of width of a measuring surface is aligned with a center of width of the wire in a direction perpendicular to a longitudinal axis of the wire, the width of the measuring surface is 20% or more and 40% or less of a diameter of the wire, and a length of the measuring surface is five times the width of the measuring surface.