METHOD FOR MANUFACTURING PIEZOELECTRIC DEVICE, PIEZOELECTRIC DEVICE, AND PIEZOELECTRIC FREE-STANDING SUBSTRATE

摘要

A piezoelectric substrate (22) and a supporting substrate (27) are prepared (step (a)); a composite substrate (20) is obtained by bonding these substrates with an adhesive layer (26) being interposed therebetween (step (b)); and the piezoelectric substrate (22) is reduced in the thickness by polishing a surface of the piezoelectric substrate (22), said surface being on the reverse side of the surface bonded to the supporting substrate (27) (step (c)). After that, a groove (28) that divides the piezoelectric substrate (22) into pieces having a size for a piezoelectric device is formed by half-dicing the composite substrate (20) from the surface of the piezoelectric substrate (22), said surface being on the reverse side of the surface bonded to the supporting substrate (27) (step (d)). Meanwhile, the adhesive layer (26) is exposed within the groove (28) by forming the groove (28). The composite substrate (20) is then immersed into a solvent, so that the adhesive layer (26) is removed by means of the solvent, thereby separating the piezoelectric substrate (22) from the supporting substrate (steps (e) and (f)). A piezoelectric device (10) is obtained using a separated piezoelectric substrate (12) (step (g)).