Provided is a piezoelectric device including: a substrate (10) on which a plurality of recesses (12) are provided; a vibrating plate (50) which is provided on one surface side of the substrate; and a piezoelectric element (300) which is provided over the vibrating plate (50) and on which a first electrode (60), a piezoelectric layer (70), and a second electrode (80) are laminated from the substrate (10) side, in which the first electrode (60) is formed to have a first width which is smaller than a dimension of the recess in a parallel arrangement direction in the parallel arrangement direction of at least one recess (12), and the piezoelectric layer (70) is extended to the outer side of the first electrode (60) in the parallel arrangement direction and has a second width which is greater than the first width and smaller than a width of the recess (12) in the parallel arrangement direction, the vibrating plate (50) contains a zirconium oxide layer (52), and when an area of the zirconium oxide layer (52) corresponding to the first electrode having the first width is set as a first area (p), areas of the zirconium oxide layer (52) corresponding to areas where the piezoelectric layer (70) is provided on the outer side of the first area (p) in the parallel arrangement direction are set as second areas (q), and areas of the zirconium oxide layer (52) corresponding to the recess (12) on the outer side of the second areas (q) in the parallel arrangement direction are set as third areas (r), the zirconium oxide layer (52) contains particulate crystal in the first area (p) at least on the first electrode (60) side in the thickness direction and contains columnar crystal in the third areas (r).

A thermal sensor circuit comprises a conversion circuit which is one of a buck DC-DC converter circuit and a boost DC-DC converter circuit, wherein the conversion circuit comprises an inductor and an output terminal. A thermal sensor senses a thermal variation correlated to a capacitance variation of the thermal sensor. The capacitance variation induces an internal parasitic capacitance variation of the inductor which is connected in parallel to the thermal sensor and results a variation of an energy stored in the inductor. Hence a variation of a converted circuit signal outputting by the output terminal is caused, wherein the variation of the converted circuit signal is correlated to the thermal variation.

A liquid discharge head is provided. The liquid discharge head includes: a semiconductor substrate including a first pressure chamber; an insulating film disposed above the semiconductor substrate; a first piezoelectric element disposed on an opposite side to the first pressure chamber of the insulating film and having a piezoelectric layer and a first and second electrode; and a doped layer formed in the semiconductor substrate. The doped layer partitions at least part of the first pressure chamber and has a lower electrical resistivity than the insulating film and the semiconductor substrate. A through hole having a conductor disposed on its inside is formed in the insulating film, and the first electrode and the doped layer are electrically continuous via the conductor.

A piezoelectric device including a substrate, at least two electrodes extending on the substrate, at least one piezoelectric strip extending on the substrate and on the electrodes, and at least one electrically-conductive strip extending at least on one of the electrodes and on the piezoelectric strip and in contact with the substrate on either side of the piezoelectric strip.

A composite substrate of the present disclosure is a composite substrate in which a piezoelectric substrate and a sapphire substrate are directly bonded, and a bonding surface of the sapphire substrate has a step bunch structure. A piezoelectric device of the present disclosure includes the composite substrate. A method for manufacturing a composite substrate includes the steps of: preparing a piezoelectric substrate and a sapphire substrate including a surface having a predetermined off-angle to a specific crystal plane, heat treating the sapphire substrate in an oxidizing atmosphere to form a step bunch on the surface of the sapphire substrate, and bonding the piezoelectric substrate and the surface of the sapphire substrate directly.

In some embodiments, a piezoelectric device is provided. The piezoelectric device includes a semiconductor substrate. A first electrode is disposed over the semiconductor substrate. A piezoelectric structure is disposed on the first electrode. A second electrode is disposed on the piezoelectric structure. A heating element is disposed over the semiconductor substrate. The heating element is configured to heat the piezoelectric structure to a recovery temperature for a period of time, where heating the piezoelectric structure to the recovery temperature for the period of time improves a degraded electrical property of the piezoelectric device.

A piezoelectric element application device according to the disclosure includes: a vibration plate made of silicon oxide; a first electrode formed above the vibration plate; a seed layer formed above the first electrode and the vibration plate; a piezoelectric layer formed at the seed layer and containing potassium, sodium, and niobium; and a second electrode formed at the piezoelectric layer. The vibration plate further contains potassium and sodium. In secondary ion mass spectrometry on the vibration plate and the piezoelectric layer, an intensity of potassium in the vibration plate is lower than an intensity of potassium in the piezoelectric layer, and an intensity of sodium in the vibration plate is lower than an intensity of sodium in the piezoelectric layer.

A SAW device (1) comprises a substrate (3); SAW elements (10) on a first main surface (3a) of the substrate (3); first lines (intermediate lines (29) and output side lines (31)) that are disposed upon the first main face (3a) and connected to the SAW elements (10); an insulator (21) that is layered upon the first lines; second lines (a second ground line (33b) and a third ground line (33c)) that are layered upon the insulator (21) and configure three-dimensional wiring parts (39) with the first lines; and a cover (5) that seals the SAW elements (10) and the three-dimensional wiring parts (39). Wiring spaces (53), formed between the first main face (3a) and the cover (5), houses the three-dimensional wiring parts (39), without housing the SAW elements (10).

The present disclosure discloses a piezoelectric sensor and a method for manufacturing the same to realize omni-directional pressure sensing. The piezoelectric sensor according to the present disclosure comprises a first electrode layer, a second electrode layer and a piezoelectric thin film layer between the first electrode layer and the second electrode layer, the piezoelectric sensor further comprising: a first functional module and a second functional module, both of which are connected to the second electrode layer, wherein the first functional module is configured to sense a pressure applied to the piezoelectric sensor in a first direction, and the second functional module is configured to sense a pressure applied to the piezoelectric sensor in a second direction, the first direction and the second direction are perpendicular to each other.

A haptic stimulator includes a multilayer sheet with a piezoelectric or electroactive polymer layer adapted to mechanically deform upon application of voltage, the multilayer sheet secured to a substrate, and a source of electrical stimulation coupled to drive electrodes on the polymer layer with an AC signal to vibrate the polymer layer. In particular embodiments, the polymer contains polyvinylidene fluoride, and electrodes are patterned to control local electric fields. Another haptic stimulator has first and second electrodes with an air gap and an insulating sheet between first and second electrodes, with an AC voltage driver connecting to the electrodes. In a method of providing haptic stimulation to skin an alternating current supply drives first and second electrodes, the electrodes disposed upon either a piezoelectric or electroactive polymer sheet, vibrating the polymer layer by driving the electrodes; and coupling vibrations of the polymer layer to the sensate skin.