US 12,082,504 B2
Composite substrate, piezoelectric device, and method for manufacturing composite substrate
Motohiro Umehara, Yasu (JP); and Kuniaki Mitsuda, Omihachiman (JP)
Assigned to Kyocera Corporation, Kyoto (JP)
Appl. No. 17/272,490
Filed by KYOCERA Corporation, Kyoto (JP)
PCT Filed Sep. 6, 2019, PCT No. PCT/JP2019/035146
§ 371(c)(1), (2) Date Mar. 1, 2021,
PCT Pub. No. WO2020/050396, PCT Pub. Date Mar. 12, 2020.
Claims priority of application No. 2018-167072 (JP), filed on Sep. 6, 2018.
Prior Publication US 2021/0320243 A1, Oct. 14, 2021
Int. Cl. H10N 30/072 (2023.01); H03H 9/02 (2006.01); H10N 30/00 (2023.01)
CPC H10N 30/072 (2023.02) [H03H 9/02574 (2013.01); H10N 30/706 (2024.05)] 11 Claims
OG exemplary drawing
 
1. The composite substrate comprising a piezoelectric substrate and a sapphire substrate which are directly bonded,
wherein the sapphire substrate has a step bunch on a bonding surface with the piezoelectric substrate.