A piezoelectric driving device includes: a driving portion to be brought into frictional contact with an object to be driven, which is moved with respect to a fixed body; and at least two piezoelectric portions, which are formed integrally with the driving portion, are arranged on a predetermined plane with the driving portion being sandwiched between the at least two piezoelectric portions, and are configured to be bent with respect to the predetermined plane when voltages are applied to the at least two piezoelectric portions, wherein outer edges of entirety of the at least two piezoelectric portions are fixed to the fixed body.

According to one embodiment, a cantilever array includes a plurality of cantilever pairs. Each of the cantilever pairs includes a first cantilever and a second cantilever facing the first cantilever while having a gap, and which are arrayed in a direction orthogonal to a facing direction. Positions of the gaps of the cantilever pairs shift from each other when viewing in an array direction.

The piezoelectric laminate and the piezoelectric element have, on a substrate in the following order, a lower electrode layer and a piezoelectric film containing a perovskite-type oxide, in which the lower electrode layer contains a Ta element, contains a Ta nitride on a side closest to the piezoelectric film in a thickness direction of the lower electrode layer, and includes a region where a content of the Ta element changes in the thickness direction, and the change in the content of the Ta element in the thickness direction is continuous.

The piezoelectric laminate and the piezoelectric element have, on a substrate in the following order, a lower electrode layer and a piezoelectric film containing a perovskite-type oxide, in which the lower electrode layer includes the metal layer containing Ni and a surface layer containing a Ni oxide or a Ni oxynitride, and in the lower electrode layer, the surface layer is arranged on the side closest to the piezoelectric film.

PMUT acoustic transducer formed in a body of semiconductor material having a face and accommodating a plurality of first buried cavities, having an annular shape, arranged concentrically with each other and extending at a distance from the face of the body. The first buried cavities delimit from below a plurality of first membranes formed by the body so that each first membrane extends between a respective first buried cavity of the plurality of first buried cavities and the face of the body. A plurality of piezoelectric elements extend on the face of the body, each piezoelectric element extending above a respective first membrane of the plurality of first membranes. The first membranes have different widths, variable between a minimum value and a maximum value.

An object of the present invention is to provide a piezoelectric element formed of a piezoelectric film including an electrode layer provided on each of both surfaces of a piezoelectric layer and a protective layer provided on the surface of the electrode layer, in which the electrode layer and a conductive member such as a lead wire can be connected to each other with high productivity and the resistance of the connection is also low. The object thereof is achieved by opening through-holes in the protective layer of the piezoelectric film and the conductive member, allowing both through-holes to at least partially overlap each other, filling the through-hole of the protective layer with a conductive filling member, and allowing the filling member to reach the through-hole of the conductive member.

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.

A method of making a piezoelectric sensor includes forming piezoelectric layer(s) to define a beam extending between a proximal portion and a distal end. The method also includes modeling a strain distribution on the beam based on a force applied to the beam, and defining an outer boundary with a shape substantially corresponding to a contour line of the strain distribution on the beam. The method also includes forming an electrode having said outer boundary shape, and attaching the electrode to the beam. The method also includes attaching the beam to a substrate in cantilever form so that the proximal portion of the beam is anchored to the substrate and the distal end of the beam is unsupported.

A method of making a piezoelectric sensor includes forming piezoelectric layer(s) to define a beam extending between a proximal portion and a distal end. The method also includes modeling a strain distribution on the beam based on a force applied to the beam, and defining an outer boundary with a shape substantially corresponding to a contour line of the strain distribution on the beam. The method also includes forming an electrode having said outer boundary shape, and attaching the electrode to the beam. The method also includes attaching the beam to a substrate in cantilever form so that the proximal portion of the beam is anchored to the substrate and the distal end of the beam is unsupported.

A crystal oscillator (101) includes: a piezoelectric resonator plate (2) on which a first excitation electrode and a second excitation electrode are formed; a first sealing member (3) covering the first excitation electrode of the piezoelectric resonator plate (2); a second sealing member (4) covering the second excitation electrode of the piezoelectric resonator plate (2); and an internal space (13) formed by bonding the first sealing member (3) to the piezoelectric resonator plate (2) and by bonding the second sealing member (4) to the piezoelectric resonator plate (2), so as to hermetically seal a vibrating part including the first excitation electrode and the second excitation electrode of the piezoelectric resonator plate (2). An electrode pattern (371) including a mounting pad for wire bonding is formed on an outer surface (first main surface (311)) of the first sealing member (3).