Methods and assemblies related to fabrication of acoustic wave devices. In some embodiments, a method for fabricating an acoustic wave device can include attaching a first surface of a piezoelectric layer, such as a LiTaO3 or LiNbO3 layer, to a handling substrate, and performing a thinning operation on the piezoelectric layer to expose a second surface of a reduced-thickness piezoelectric layer attached to the handling substrate. The method can further include bonding the second surface of the reduced-thickness piezoelectric layer to a first surface of a permanent substrate, and removing the handling substrate from the reduced-thickness piezoelectric layer. The handling substrate can be, for example, a silicon substrate, and the permanent substrate can be, for example, a quartz substrate.