US 12,237,824 B2
Composite substrate, elastic wave element, and production method for composite substrate
Yuji Hori, Owariasahi (JP); and Takahiro Yamadera, Nagoya (JP)
Assigned to NGK INSULATORS, LTD., Nagoya (JP)
Filed by NGK INSULATORS, LTD., Nagoya (JP)
Filed on Dec. 8, 2021, as Appl. No. 17/545,507.
Application 17/545,507 is a continuation of application No. PCT/JP2020/006285, filed on Feb. 18, 2020.
Claims priority of application No. 2019-108407 (JP), filed on Jun. 11, 2019.
Prior Publication US 2022/0103155 A1, Mar. 31, 2022
Int. Cl. H03H 9/02 (2006.01); H03H 3/10 (2006.01); H10N 30/072 (2023.01)
CPC H03H 9/02574 (2013.01) [H03H 3/10 (2013.01); H03H 9/02559 (2013.01); H03H 9/02834 (2013.01); H10N 30/072 (2023.02)] 5 Claims
OG exemplary drawing
 
1. A composite substrate comprising:
a supporting substrate comprising quartz;
a piezoelectric material substrate comprising a material selected from the group consisting of lithium niobate, lithium tantalate and lithium niobate-lithium tantalate; and
an interface layer along a bonding interface between said supporting substrate and said piezoelectric material substrate, said interface layer having amorphous structure and comprising constituent components including silicon, oxygen and at least one of tantalum and niobium,
wherein said interface layer has concentrations of hydrogen atoms, nitrogen atoms and fluorine atoms of 1×1018 atoms/cm 3 or higher and 5×1021 atoms/cm 3 or lower, respectively.