IMPROVING THE STABILITY OF RESONANT FREQUENCY OF PIEZOELECTRIC DEVICE

摘要

Piezoelectric device comprising a protective housing containing a piezoelectric body bearing aluminium film electrodes. The surfaces of the electrodes which are not in contact with the piezoelectric body bear a passivating layer of amorphous aluminium oxide. The amorphous aluminum oxide layer may be made by heating the electrodes at a temperature between 250 and 550.degree.C in an atmosphere containing free oxygen. The piezoelectric device may be, for example an acoustic surface wave device.