US 12,325,908 B2
Platinum-based sputtering target, and method for producing the same
Akihito Fujino, Isehara (JP); Kunihiro Tanaka, Isehara (JP); Shuichi Kubota, Isehara (JP); Takao Asada, Isehara (JP); Tetsuo Endoh, Sendai (JP); and Shoji Ikeda, Sendai (JP)
Assigned to TOHOKU UNIVERSITY, Sendai (JP); and TANAKA KIKIZOKU KOGYO K.K., Tokyo (JP)
Appl. No. 18/036,827
Filed by TOHOKU UNIVERSITY, Sendai (JP); and TANAKA KIKINZOKU KOGYO K.K., Tokyo (JP)
PCT Filed Nov. 15, 2021, PCT No. PCT/JP2021/041818
§ 371(c)(1), (2) Date May 12, 2023,
PCT Pub. No. WO2022/102765, PCT Pub. Date May 19, 2022.
Claims priority of application No. 2020-189958 (JP), filed on Nov. 16, 2020.
Prior Publication US 2023/0407459 A1, Dec. 21, 2023
Int. Cl. C23C 14/34 (2006.01); C23C 14/14 (2006.01)
CPC C23C 14/3414 (2013.01) [C23C 14/14 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A platinum-based sputtering target comprising platinum or a platinum alloy,
wherein when a thickness-direction cross section is equally divided into n sections (n=5 to 20) along a thickness direction, a region including (n−2) sections excluding both end sections is set as a determination region, and an average grain size in each of the sections is measured in the determination region, as well as an average grain size in the entire determination region is measured,
the average grain size in the entire determination region is 150 μm or less, and
a coefficient of variation calculated based on the average grain size in each of the sections of the determination region is 15% or less, and,
in the determination region, a number-based proportion of crystal grains having an aspect ratio of 3 or more is 20% or less, and a number-based proportion of crystal grains having an aspect ratio of 5 or more is 9% or less.