US 11,795,540 B2
Gold sputtering target and method for producing the same
Tetsuya Kato, Tomioka (JP); Takashi Terui, Tomioka (JP); and Masahiro Takahashi, Tomioka (JP)
Assigned to TANAKA KIKINZOKU KOGYO K. K., Tokyo (JP)
Filed by TANAKA KIKINZOKU KOGYO K. K., Tokyo (JP)
Filed on Dec. 19, 2022, as Appl. No. 18/67,863.
Application 18/067,863 is a division of application No. 16/893,135, filed on Jun. 4, 2020, granted, now 11,560,620.
Application 16/893,135 is a continuation of application No. PCT/JP2018/044584, filed on Dec. 4, 2018.
Claims priority of application No. 2017-234720 (JP), filed on Dec. 6, 2017.
Prior Publication US 2023/0120540 A1, Apr. 20, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. C23C 14/34 (2006.01)
CPC C23C 14/3414 (2013.01) 4 Claims
 
1. A production method for a gold sputtering target, comprising:
preparing a gold ingot having a gold purity of 99.999% or more,
processing the gold ingot to form a gold billet, and
producing a gold sputtering target having a gold purity of 99.999% or more from the gold billet, in which an average value of Vickers hardness is 20 or more and less than 40, an average crystal grain size is 15 μm or more and 200 μm or less, and a plane of gold is preferentially oriented to a surface to be sputtered of the gold sputtering target and
wherein the surface to be sputtered is subjected to X-ray diffraction, and an orientation index N of crystal planes of gold are determined according to the following equation (1) based on a diffraction intensity ratio of each of the crystal planes of gold, the orientation index N of the plane of gold is larger than 1 and the largest among the orientation indices N of all the crystal planes:

OG Complex Work Unit Math
where I/I(hkl) is the diffraction intensity ratio of an (hkl) plane in the X-ray diffraction, JCPDS·I/I(hkl) is the diffraction intensity ratio of the (hkl) plane in JCPDS card for gold, Σ(I/I(hkl)) is the sum of the diffraction intensity ratios of all the crystal planes in the X-ray diffraction, and Σ(JCPDS·I/I(hkl)) is the sum of the diffraction intensity ratios of all the crystal planes provided on the JCPDS card for gold.