| 摘要 |
A composite substrate 10 includes a supporting substrate 12 and a piezoelectric substrate 14 which are bonded to each other. In this embodiment, the supporting substrate 12 and the piezoelectric substrate 14 are bonded to each other by an adhesive layer 16. In the composite substrate 10, since the supporting substrate 12 is composed of a translucent alumina ceramic, alignment is easily performed during FCB compared with the case where the supporting substrate is composed of an opaque ceramic. Furthermore, preferably, the linear transmittance and the total light transmittance from the front of the supporting substrate 12 in the visible light range (360 to 750 nm) are 10% or more and 70% or more, respectively. |
