Piezoelectric/electrostrictive element
AssigneeNGK Insulators, Ltd.
InventorsHirofumi Yamaguchi, Nobuo Takahashi
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Abstract
A ceramic substrate 1 comprises a thin diaphragm portion 3 and a thick portion 2. A lower electrode 4 is formed on the ceramic substrate and is spaced apart from an auxiliary electrode 8, also formed on the ceramic substrate. A bonding layer 7C comprises an insulator and is formed on the ceramic substrate between the lower and auxiliary electrodes. A piezoelectric/electrostrictive layer 5 is formed on at least a portion of each of the lower electrode, the auxiliary electrode and the bonding layer. An upper electrode 6 extends over the piezoelectric/electrostrictive layer and contacts the auxiliary electrode. A bonded portion exists wherein the bonding layer serves to completely bond together the substrate and the piezoelectric/electrostrictive film layer.
Claims6
A piezoelectric/electrostrictive element comprising:
- a ceramic substrate having a thin diaphragm portion and a thick portion;
- a lower electrode formed on a surface of the ceramic substrate;
- an auxiliary electrode formed on the surface of the ceramic substrate at a location spaced apart from said lower electrode;
- an insulating bonding layer formed on the surface of the ceramic substrate between the lower electrode and the auxiliary electrode;
- a piezoelectric/electrostrictive layer formed on at least a portion of the lower electrode, at least a portion of the bonding layer and at least a portion of the auxiliary electrode;
- and
- an upper electrode formed on the piezoelectric/electrostrictive layer;
- wherein the bonding layer forms a completely bonded part comprising portions of the ceramic substrate, the lower electrode, the auxiliary electrode and the piezoelectric/electrostrictive layer.
Dependencies are inferred from the claim text.