A method of manufacturing a piezoelectric microactuator having a wrap-around electrode includes forming a piezoelectric element having a large central electrode on a top face, and having a wrap-around electrode that includes the bottom face, two opposing ends of the device, and two opposing end portions of the top face. The device is then cut through the middle, separating the device into two separate piezoelectric microactuators each having a wrap-around electrode.

A piezoelectric device includes a piezoelectric vibrating piece, an excitation electrode, an extraction electrode, a container, a pad, a conductive member, and a heat conductive metal film. The excitation electrode is disposed on a front surface and a back surface of the piezoelectric vibrating piece. The extraction electrode is extracted from the excitation electrode. The container houses the piezoelectric vibrating piece. The pad is disposed in the container, and the pad is connected to the piezoelectric vibrating piece. The conductive member connects the pad to the extraction electrode. The heat conductive metal film is disposed at least on a surface of a pad side of the piezoelectric vibrating piece, the heat conductive metal film is extracted from the extraction electrode without contacting the excitation electrode.

A piezoelectric element having a piezoelectric body and an electrode in contact with the piezoelectric body: the piezoelectric body being formed of a lead-free piezoelectric ceramic composition which includes a primary phase formed of an alkali niobate-based perovskite oxide represented by a compositional formula (A1.sub.aM1.sub.b)c(Nb.sub.d1Mn.sub.d2Ti.sub.d3Zr.sub.d4Hf.sub.d5)O.sub.3+e (wherein element A1 represents at least one species among the alkali metals; element M1 represents at least one species among Ba, Ca, and Sr; the following conditions: 0<a<1, 0<b<1, a+b=1, 0.80<c<1.10, 0<d1<1, 0<d2<1, 0<d3<1, 0?d4<1, 0?d5<1, and d1+d2+d3+d4+d5=1, are satisfied; and e represents a value showing the degree of deficiency or excess of oxygen) and which satisfies the condition: b/(d3+d4+d5)?1, and the electrode containing a base metal as a main component.

A piezoelectric element having a piezoelectric body and an electrode in contact with the piezoelectric body: the piezoelectric body being formed of a lead-free piezoelectric ceramic composition which includes a primary phase formed of an alkali niobate-based perovskite oxide represented by a compositional formula (A1.sub.aM1.sub.b)c(Nb.sub.d1Mn.sub.d2Ti.sub.d3Zr.sub.d4Hf.sub.d5)O.sub.3+e (wherein element A1 represents at least one species among the alkali metals; element M1 represents at least one species among Ba, Ca, and Sr; the following conditions: 0<a<1, 0<b<1, a+b=1, 0.80<c<1.10, 0<d1<1, 0<d2<1, 0<d3<1, 0?d4<1, 0?d5<1, and d1+d2+d3+d4+d5=1, are satisfied; and e represents a value showing the degree of deficiency or excess of oxygen) and which satisfies the condition: b/(d3+d4+d5)?1, and the electrode containing a base metal as a main component.

A preparation method for a piezoelectric fiber is provided including a piezoelectric functional layer and an insulating layer coated on the piezoelectric functional layer. The piezoelectric functional layer includes a piezoelectric composite layer of a spiral winding structure, and the piezoelectric composite layer includes a first piezoelectric layer, a conductive layer and a second piezoelectric layer that are sequentially stacked. The preparation method includes taking one end of the piezoelectric composite layer as a winding axis, winding the piezoelectric composite layer in a direction perpendicular to the winding axis to form the piezoelectric functional layer, wherein turns of winding the piezoelectric composite layer are greater than 5, coating the piezoelectric functional layer with the insulating layer, and vacuum heating to consolidate, to prepare a preform rod.

A preparation method for a piezoelectric fiber is provided including a piezoelectric functional layer and an insulating layer coated on the piezoelectric functional layer. The piezoelectric functional layer includes a piezoelectric composite layer of a spiral winding structure, and the piezoelectric composite layer includes a first piezoelectric layer, a conductive layer and a second piezoelectric layer that are sequentially stacked. The preparation method includes taking one end of the piezoelectric composite layer as a winding axis, winding the piezoelectric composite layer in a direction perpendicular to the winding axis to form the piezoelectric functional layer, wherein turns of winding the piezoelectric composite layer are greater than 5, coating the piezoelectric functional layer with the insulating layer, and vacuum heating to consolidate, to prepare a preform rod.

A micro-electrical-mechanical system (MEMS) guided wave device includes a single crystal piezoelectric layer and at least one guided wave confinement structure configured to confine a laterally excited wave in the single crystal piezoelectric layer. A bonded interface is provided between the single crystal piezoelectric layer and at least one underlying layer. A multi-frequency device includes first and second groups of electrodes arranged on or in different thickness regions of a single crystal piezoelectric layer, with at least one guided wave confinement structure. Segments of a segmented piezoelectric layer and a segmented layer of electrodes are substantially registered in a device including at least one guided wave confinement structure.

A piezoelectric member including metal electrodes with improved adhesiveness to piezoelectric elements is to be provided. A piezoelectric member 102 includes a piezoelectric element 21, and a pair of electrodes 41, 42 respectively formed on a pair of opposing surfaces 21b, 21c of the piezoelectric element 21. The electrodes 41, 42 includes: a base film 41a that is formed on the opposing surfaces 21b, 21c of the piezoelectric element 21 and contains a thiol group; a metal adhesive film 41b formed on the base film 41a; and an electrode film 41c that is formed on the metal adhesive film 41b and is for applying voltage to the piezoelectric element 21. The metal adhesive film 41b is formed with a different material from the electrode film 41c, and has a thickness of 1 to 10 nm.

An electronics package includes a semiconductor substrate having one or more passive devices formed thereon and a cavity defined in a first surface thereof. A piezoelectric substrate is bonded to the semiconductor substrate and has a radio frequency (RF) filter formed thereon. The RF filter is disposed within the cavity defined in the semiconductor substrate.

A micro-electrical-mechanical system (MEMS) guided wave device includes a piezoelectric layer including multiple thinned regions of different thicknesses each bounding in part a different recess, different groups of electrodes on or adjacent to different thinned regions and arranged for transduction of lateral acoustic waves of different wavelengths in the different thinned regions, and at least one bonded interface between the piezoelectric layer and a substrate. Optionally, a buffer layer may be intermediately bonded between the piezoelectric layer and the substrate. Methods of producing such devices include locally thinning a piezoelectric layer to define multiple recesses, bonding the piezoelectric layer on or over a substrate layer to cause the recesses to be bounded in part by either the substrate or an optional buffer layer, and defining multiple groups of electrodes on or over the different thinned regions.