Patent ID: 7528681

Claim:
A method of forming an acoustical device comprising: providing a first substrate having a first surface and a second surface where the substrate is one of an r-plane sapphire, aluminum oxide (Al 2 O 3 ) or aluminum nitride (AlN); growing a single crystal piezoelectric region having a first surface and a second surface, the single crystal piezoelectric region located on the first surface of the first substrate, wherein the first surface of the single crystal piezoelectric region and the first surface of the substrate are in direct contact; depositing a first electrode layer on a second surface of the single crystal piezoelectric region; performing a laser lift-off process including employing a radiation source to break a bond between the first surface of the first substrate and the first surface of the single crystal piezoelectric region to separate the first substrate and the single crystal piezoelectric region; performing a laser trimming process with the radiation source; smoothing the surface of the first surface of the single crystal piezoelectric region through polishing techniques in order to tune the first surface of the single crystal piezoelectric region to operate at a specific resonant frequency; and depositing a second electrode layer on the first surface of the single crystal piezoelectric region.