US 12,359,300 B2
Method for producing ferroelectric film, ferroelectric film, and usage thereof
Hiroshi Funakubo, Tokyo (JP); Takao Shimizu, Tokyo (JP); Takanori Mimura, Tokyo (JP); Yoshiko Nakamura, Tokyo (JP); Reijiro Shimura, Tokyo (JP); and Yu-ki Tashiro, Tokyo (JP)
Assigned to Tokyo Institute of Technology, Tokyo (JP)
Appl. No. 17/606,440
Filed by Tokyo Institute of Technology, Tokyo (JP)
PCT Filed Apr. 27, 2020, PCT No. PCT/JP2020/018031
§ 371(c)(1), (2) Date Oct. 25, 2021,
PCT Pub. No. WO2020/218617, PCT Pub. Date Oct. 29, 2020.
Claims priority of application No. 2019-086836 (JP), filed on Apr. 26, 2019; and application No. 2019-086840 (JP), filed on Apr. 26, 2019.
Prior Publication US 2022/0178012 A1, Jun. 9, 2022
Int. Cl. C23C 14/08 (2006.01); C01G 27/00 (2006.01); C01G 27/02 (2006.01); C23C 14/34 (2006.01); C23C 14/58 (2006.01); H01L 21/02 (2006.01); H10N 30/077 (2023.01); C30B 29/22 (2006.01)
CPC C23C 14/083 (2013.01) [C01G 27/006 (2013.01); C01G 27/02 (2013.01); C23C 14/34 (2013.01); C23C 14/5806 (2013.01); H10N 30/077 (2023.02); C30B 29/22 (2013.01); H01L 21/02197 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A production process of a ferroelectric film, which comprises
using a sputtering method comprising sputtering a target at a temperature of a substrate of 250° C. or lower, to deposit on the substrate a film of a metal oxide which is capable of having a fluorite-type structure of an orthorhombic crystal phase, and
having a thermal history of said film of 250° C. or lower at the time of said sputtering and after said sputtering, or applying an electric field to said film which has a thermal history of 250° C. or lower at the time of said sputtering and after said sputtering,
whereby a ferroelectric film comprising a crystalline metal oxide having a fluorite-type structure of an orthorhombic crystal phase is produced.