Piezoelectric membrane, piezoelectric device, and inkjet head

A piezoelectric device comprising:

• a lower electrode;
• a piezoelectric membrane that is disposed on the lower electrode and that includes a columnar structure layer and an amorphous structure layer of a piezoelectric material, the columnar structure layer being a layer deposited on the lower electrode according to a sputtering method, the amorphous structure layer being a layer formed by depositing a piezoelectric material according to a sol-gel method as stacked contiguously with the columnar structure layer;
• and
• an upper electrode that is disposed on the piezoelectric membrane and that faces the lower electrode with the piezoelectric membrane interposed between the upper electrode and the lower electrode.

An inkjet head comprising:

• a substrate that defines a cavity in which ink is stored;
• a vibrating membrane that is supported by the substrate and that defines the cavity;
• and
• a piezoelectric device that is disposed on the vibrating membrane and that changes a volume of the cavity by displacing the vibrating membrane;
• the piezoelectric device comprising:
• a lower electrode;
• a piezoelectric membrane that is disposed on the lower electrode and that includes a columnar structure layer and an amorphous structure layer of a piezoelectric material, the columnar structure layer being a layer deposited on the lower electrode according to a sputtering method, the amorphous structure layer being a layer formed by depositing a piezoelectric material according to a sol-gel method as stacked contiguously with the columnar structure layer;
• and
• an upper electrode that is disposed on the piezoelectric membrane and that faces the lower electrode with the piezoelectric membrane interposed between the upper electrode and the lower electrodes.