A semiconductor structure is provided. The semiconductor structure includes a substrate, a first piezoelectric layer, and a first dummy layer. The first piezoelectric layer is over the substrate, and the first piezoelectric layer has a first top surface. The first dummy layer is over the first piezoelectric layer, and the first dummy layer has a second top surface. And an average roughness of the first top surface is greater than an average roughness of the second top surface. A method for manufacturing the semiconductor structure is also provided.

A manufacturing method for an electrode of a high-temperature piezoelectric element, comprises: coating traditional conductive slurry on surfaces of a molded piezoelectric material (1); then polarizing the piezoelectric material (1); and then removing the coating of conductive slurry (2) on the surfaces there of, and connecting the piezoelectric material to outside electrode lead wires (3) to output a signal generated by piezoelectric effect thereof. A structure of a high-temperature piezoelectric element, comprises polarized piezoelectric material (1), wherein the coating of metallic conductive slurry (2) is removed from the surfaces of the polarized piezoelectric material (1) and the surfaces of the polarized piezoelectric material (1) is connected to electrode lead wires (3) to output a signal generated by piezoelectric effect thereof. By removing the traditional coating of slurry for electrode, it is avoided that the output resistance of the piezoelectric element is reduced because of the high temperature diffusion of electrode material at a high temperature, and the thermal performance of the piezoelectric element is improved. By adding diamond or graphite coating as electrode, the sensitivity of outputting charges of the piezoelectric element is improved.

An acoustic wave device includes a piezoelectric substrate including an electrode formation surface, and an IDT electrode provided on the electrode formation surface. The IDT electrode includes a close contact layer located on the electrode formation surface, and a main electrode layer located on the close contact layer. The close contact layer includes first and second layers that respectively include first and second lateral surfaces. An area of a surface of the second layer that is in close contact with the main electrode layer is smaller than an area of a surface of the first layer that is in close contact with the piezoelectric substrate. An inclination angle of the second lateral surface is smaller than an inclination angle of the first lateral surface.

A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.

The present invention relates to a energy conversion device (100) configured to convert a light signal into an electrical signal, comprising: an actuator element (50), substantially planar, having at least one activatable portion (30), said activatable portion comprising a photomobile polymeric material; a transducer element (60), substantially planar, having at least a portion of piezoelectric material; wherein said actuator element (50) is coupled to said transducer element (60) so that, at a light beam incident on said photomobile polymeric material, a movement of said transducer element (60) is activated through a movement of said activatable portion (30), said movement of said transducer element (60) providing the generation of a potential difference at the terminal ends of said portion of piezoelectric material.

The present invention also relates to a method of production of the aforesaid device.

A magnetic tunnel junction (MTJ) device includes two magnetic tunnel junction elements and a metal interconnection. The two magnetic tunnel junction elements are arranged side by side at a first direction. The metal interconnection is disposed between the magnetic tunnel junction elements, wherein the metal interconnection includes a contact plug part having a long shape at a top view, and the long shape has a length at a second direction larger than a width at the first direction, wherein the second direction is orthogonal to the first direction.

A method of fabricating the semiconductor device includes the following steps. Forming a sacrificial portion at a first end of an upper electrode layer before a passivation layer is formed so that it supports a corresponding end portion of the passivation layer, making the passivation layer not suspended at all. In this way, the suspended portion of the passivation layer will not be damaged during the formation of a contact pad. In addition, subsequent to the formation of the contact pad, removing the sacrificial portion, freeing up a space under the end portion of the passivation layer so that the end portion itself becomes a suspended portion. This can ensure performance of the resulting semiconductor device.

A piezoelectric material includes a metal oxide containing at least Ba, Ca, Ti, Zr, and Mn, in which the piezoelectric material has a perovskite structure, in which: x, which represents a ratio of a content (mol) of Ca to A (mol) representing a total content of Ba and Ca, falls within a range of 0.10x0.18; y, which represents a ratio of a content (mol) of Zr to B (mol) representing a total content of Ti, Zr, and Mn, falls within a range of 0.055y0.085; and z, which represents a ratio of a content (mol) of Mn to the B (mol), falls within a range of 0.003z0.012, and in which the piezoelectric material satisfies a relationship of 0(|d.sub.31(20u)d.sub.31(20d)|)/|d.sub.31(20u)|0.08, and has a value of 130 pm/V or more for each of |d.sub.31(20u)| and |d.sub.31(20d)|.

A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.

An elastomer piezoelectric element is configured by alternately disposing first opposite electrodes and second opposite electrodes, and sandwiching a dielectric layer between each first opposite electrode and the corresponding second opposite electrode. Each of the dielectric layers includes a dielectric elastomer sheet-shaped dielectric portion and a conductive elastomer first common electrode connecting the first opposite electrodes to each other or a conductive elastomer second common electrode connecting the second opposite electrodes to each other. The first common electrode and the second common electrode are provided so as to extend from one main surface to another main surface of the dielectric portion, and are joined to the first opposite electrode and the second opposite electrode, respectively, on a joint surface along the dielectric layer.