Structural and acoustic characterization of highly oriented piezoelectric AIN films

Aluminum nitride piezoelectric films have been grown by reactive sputtering technique on different substrates, chosen according to their attractive properties such as high acoustic wave velocity (Al 2 O 3 , MgO, Si) and possibility to integrate the acoustic device with the electric circuitry (Si, GaAs). We have studied the AlN properties within a thickness range of 2.1 - 6.3 micrometers by means of X-ray diffraction analysis and piezoelectric d 33 constants measurements, in order to define the best sputtering parameters that ensure the best quality of the AlN films.