A method is provided for fabricating piezoelectric plates. A sacrificial layer is formed overlying a growth substrate. A template layer, with openings exposing sacrificial layer surfaces, is formed over the sacrificial layer. An adhesion layer/first electrode stack is selectively deposited in the openings overlying the sacrificial layer surfaces, and a piezoelectric material formed in the openings overlying the stack. Then, a second electrode is formed overlying the piezoelectric material. Using the second electrode as a hardmask, the piezoelectric material is etched to form polygon-shaped structures, such as disks, attached to the sacrificial layer surfaces. After removing the template layer and annealing, the polygon-shaped structures are separated from the sacrificial layer. With the proper choice of growth substrate material, the annealing can be performed at a relatively high temperature.

A method for forming a pressure sensor includes forming a base of a sapphire material, the base including a cavity formed therein; forming a sapphire membrane on top of the base and over the cavity; forming a lower electrode on top of the membrane; forming a piezoelectric material layer on an upper surface of the lower electrode, the piezoelectric material layer being formed of aluminum nitride (AIN); and forming at least one upper electrode on an upper surface of the piezoelectric material layer.

A manufacturing method of an epitaxial thin film piezoelectric element includes: providing a substrate; forming a bottom electrode layer on the substrate by epitaxial growth process; forming a first piezoelectric layer that has c-axis orientation on the bottom electrode layer by epitaxial growth process; forming a second piezoelectric layer that has c-axis orientation and different phase structure from the first piezoelectric layer on the first piezoelectric layer by epitaxial growth process; and forming a top electrode layer on the second piezoelectric layer. The thin film piezoelectric element has good thermal stability, low temperature coefficient and high piezoelectric constant.

An acoustic resonator includes: a substrate; a resonance part including a lower electrode, a piezoelectric layer, and an upper electrode sequentially stacked on the substrate, and a frame formed on the upper electrode along an edge of the upper electrode; and a trench part formed in at least one side of the resonance part and making a thickness of the resonance part asymmetrical.

A piezoelectric multilayer component having a stack of sintered piezoelectric layers and inner electrodes arranged between the piezoelectric layers. A region which has poling cracks is present on the surface of at least one electrode, and the poling cracks are separated from a surface of at least one of the inner electrodes by the region having the poling cracks.

A lead-out wiring, which is connected to a comb-shaped electrode formed on a principal surface of a piezoelectric substrate and is disposed to extend to an outer edge of the piezoelectric substrate an outer surrounding wall layer, which is arranged surrounding an outer periphery of the piezoelectric substrate including the lead-out wiring and forms a hollow portion that serves as an operation space for the comb-shaped electrode, and a top board, which bridges the outer surrounding wall layer to seal the hollow portion, are included.

A piezoelectric ceramic sputtering target containing a perovskite type oxide represented by chemical formula (I) of ABO.sub.3 as a main component, wherein the component A of the chemical formula (I) contains at least K (potassium) and/or Na (sodium), the component B of the chemical formula (I) contains at least one selected from the group consisting of Nb (niobium), Ta (tantalum) and Zr (zirconium) with Nb (niobium) as a necessity, the piezoelectric ceramic sputtering target is composed of a plurality of crystal grains and grain boundaries existing among the crystal grains, and in the grain boundary, the molar ratio of at least one of Nb (niobium), Ta (tantalum), and Zr (zirconium) in the B components is higher than the molar ratio in the interior of the crystal grains by 30% or more.

The piezoelectric element comprises a piezoelectric body extending in a lateral direction and a first and second electrodes that are provided on the piezoelectric body. The piezoelectric body has an active portion sandwiched between the first and second electrodes in a thickness direction that is vertical to the lateral direction, and an inactive portion connected to the active portion in the lateral direction. The first electrode has an active electrode portion disposed on the active portion. The active electrode portion includes an interface region that is adjacent to the interface of the active portion and the inactive portion in the lateral direction, and an inner region that is separated from the interface of the active portion and the inactive portion in the lateral direction. The cross sectional surface area per unit length of the interface region in the cross section of the active electrode portion is greater than the cross sectional area per unit length of the inner region.

An ultrasonic transducer includes a stack of flat electrodes between which are interposed ceramic wafers of substantially same surface area as the electrodes, stacked contours of the ceramic wafers and electrode wafers defining substantially flat or cylindrical side faces of the stack. A method of manufacturing the transducer includes: alternatively stacking a ceramic wafer and an electrode wafer, placing between each ceramic wafer and its two neighboring electrodes a composition of which at least 75% by weight, or at least 80% by weight, that includes silver nanoparticles having a grain size of smaller than or equal to 80 nanometers, or smaller than or equal to 60 nanometers; and compressing the stack by heating to a temperature of less than or equal to 280° C., or between 200° C. and 250° C.

The present invention provides a piezoelectric material not containing lead and potassium, having a high relative density, a high Curie temperature, and a high mechanical quality factor, and exhibiting good piezoelectricity. The piezoelectric material contains 0.04 percent by mole or more and 2.00 percent by mole or less of Cu relative to 1 mol of metal oxide represented by General formula (1) below.
((Na.sub.1-zLi.sub.z).sub.xBa.sub.1-y)(Nb.sub.yTi.sub.1-y)O.sub.3 (in Formula, 0.70≦x≦0.99, 0.75≦y≦0.99, and 0<z<0.15, and x<y)  General formula (1)