US 12,237,293 B2
Palladium-coated copper bonding wire, manufacturing method of palladium-coated copper bonding wire, wire bonding structure using the same, semiconductor device and manufacturing method thereof
Hiroyuki Amano, Saga (JP); Yuki Antoku, Saga (JP); Takeshi Kuwahara, Saga (JP); Tsukasa Ichikawa, Saga (JP); Osamu Matsuzawa, Saga (JP); and Wei Chen, Saga (JP)
Assigned to TANAKA DENSHI KOGYO K. K., Kanzaki-gun (JP)
Filed by TANAKA DENSHI KOGYO K. K., Saga (JP)
Filed on Sep. 9, 2021, as Appl. No. 17/470,060.
Application 17/470,060 is a continuation of application No. PCT/JP2019/026646, filed on Jul. 4, 2019.
Claims priority of application No. 2019-045143 (JP), filed on Mar. 12, 2019.
Prior Publication US 2022/0005781 A1, Jan. 6, 2022
Int. Cl. H01L 23/495 (2006.01); H01L 23/00 (2006.01)
CPC H01L 24/45 (2013.01) [H01L 23/49582 (2013.01); H01L 24/05 (2013.01); H01L 24/48 (2013.01); H01L 2224/04042 (2013.01); H01L 2224/05624 (2013.01); H01L 2224/45147 (2013.01); H01L 2224/45664 (2013.01); H01L 2224/4845 (2013.01); H01L 2224/85035 (2013.01); H01L 2924/01016 (2013.01); H01L 2924/01034 (2013.01); H01L 2924/01052 (2013.01)] 13 Claims
OG exemplary drawing
 
13. A manufacturing method of a semiconductor device, the semiconductor device comprising: a semiconductor chip; an aluminum-containing aluminum electrode provided on the semiconductor chip; a gold or silver-coated external electrode provided outside the semiconductor chip; and a bonding wire connecting the aluminum electrode and a surface of the external electrode, wherein
the bonding wire is a palladium-coated copper bonding wire including: a core material containing copper as a main component; and a palladium layer on the core material, and containing a sulfur group element, wherein:
the palladium-coated copper bonding wire contains, relative to the total of copper, palladium, and the sulfur group element:
palladium of 1.0 mass % or more and 4.0 mass % or less; and the sulfur group element of 50 mass ppm or less in total, the sulfur group element including
sulfur of 5.0 mass ppm or more and 12.0 mass ppm or less,
selenium of 5.0 mass ppm or more and 20.0 mass ppm or less, or
tellurium of 15.0 mass ppm or more and 50.0 mass ppm or less;
in crystal orientations <hkl> in a wire longitudinal direction at a crystal plane of a cross section of the palladium-coated copper bonding wire, a <100> orientation ratio is 15% or more in total, and a <111> orientation ratio is 50% or less, the <100> orientation and the <111> orientation including an orientation with an angular difference relative to the wire longitudinal direction of within 15°; and
wherein the palladium-coated copper bonding wire is configured to form a free air ball on a tip of the palladium-coated copper bonding wire, and the free air ball includes a palladium-concentrated region containing palladium of 6.5 atom % or more and 30.0 atom % or less relative to the total of copper and palladium, in a range from a surface of a tip portion of the free air ball to 5.0 nm or more and 100.0 nm or less in a depth direction, and
the manufacturing method comprising:
forming the free air ball at the tip of the palladium-coated copper bonding wire;
ball-bonding the palladium-coated copper bonding wire to the aluminum electrode via the free air ball; and
making a portion of the palladium-coated copper bonding wire apart from the free air ball by a length of the palladium-coated copper bonding wire to be bonded to the surface of the external electrode.