Patent ID: 8764998
Filing Date: 2014-07-01
Classification: H01L,H03H

Abstract:
1. A method for manufacturing a composite substrate comprising: a pattern forming step in which a pattern region having a predetermined pattern and a reverse pattern region that is lower than the pattern region are formed on a principal surface of a piezoelectric substrate; an ion implanting step including implanting ions into the pattern region and the reverse pattern region to form a release layer inside at a certain distance from the surface of the pattern region; a bonding step in which the piezoelectric substrate at the pattern region is bonded to a flat principal surface of a supporting substrate; and a separating step in which a piezoelectric thin film is separated from the pattern region of the piezoelectric substrate, and the piezoelectric thin film is made to fall off from the reverse pattern region of the piezoelectric substrate; wherein a difference in level between the pattern region and the reverse pattern region is smaller than a thickness of the piezoelectric thin film.