An etching method for forming a vertical structure is provided. The etching method may include: positioning a mask on a substrate, wherein the mask includes an opening pattern and a compensation pattern, and the compensation pattern is disposed at a corner of two adjacent sides of the opening pattern and includes a concave compensation pattern that is indented from one of the two adjacent sides; and forming the vertical structure on the substrate through the opening pattern of the mask by a dry etching process.

The present disclosure provides a manufacturing method for a piezoelectric ceramic chip, a piezoelectric ceramic chip assembly and a display device. The manufacturing method includes: transferring a piezoelectric ceramic layer and a bottom electrode covering the piezoelectric ceramic layer formed on a substrate to a base plate, forming an insulating layer with an opening on the base plate, so that edges of the piezoelectric ceramic layer and the bottom electrode are covered by the insulating layer, and the piezoelectric ceramic layer is exposed from the opening; etching the base plate by immersing the base plate in an etching solution for etching a material of the bottom electrode; and forming a top electrode in the opening of the insulating layer, so that the top electrode is spaced apart from the insulating layer.

A piezoelectric device includes: a base having at least one hole, a heat conductive portion disposed in the at least one hole and in contact with a wall of the at least one hole, and at least one piezoelectric sensor disposed on the base. A thermal conductivity of the heat conductive portion is greater than a thermal conductivity of the base. Each piezoelectric sensor includes: a first electrode, a piezoelectric pattern made of a piezoelectric material and a second electrode that are sequentially stacked in a thickness direction of the base.

A piezoelectric device includes: a base having at least one hole, a heat conductive portion disposed in the at least one hole and in contact with a wall of the at least one hole, and at least one piezoelectric sensor disposed on the base. A thermal conductivity of the heat conductive portion is greater than a thermal conductivity of the base. Each piezoelectric sensor includes: a first electrode, a piezoelectric pattern made of a piezoelectric material and a second electrode that are sequentially stacked in a thickness direction of the base.

According to various embodiments, a PMUT device may include a wafer, an active layer including a piezoelectric stack, an intermediate layer having a cavity therein where the intermediate layer is disposed between the wafer and the active layer such that the cavity is adjoining the piezoelectric stack. A via may be formed through the active layer and the intermediate layer to the wafer. A metallic layer may be disposed over the active layer and over surfaces of the via. The intermediate layer may include an interposing material surrounding the cavity, and may further include a sacrificial material surrounding the via. The sacrificial material may be different from the interposing material. The metallic layer may include a first member at least substantially overlapping the piezoelectric stack, a second member extending from the first member to the cavity, and a third member extending into the active layer to contact an electrode therein.

An inkjet printing head 1 includes an actuator substrate 2 having pressure chambers (cavities) 7, a movable film formation layer 10 including movable films 10A disposed above the pressure chambers 7 and defining top surface portions of the pressure chambers 7, and piezoelectric elements 9 formed above the movable films 10A. Each piezoelectric element 9 includes a lower electrode 11 formed above a movable film 10A, a piezoelectric film 12 formed above the lower electrode 11, and an upper electrode 13 formed above the piezoelectric film 12. The piezoelectric film 12 includes an active portion 12A with an upper surface in contact with a lower surface of an upper electrode 13 and an inactive portion 12B led out in a direction along a front surface of the movable film formation layer 10 from an entire periphery of a side portion of the active portion 12A and having a thickness thinner than that of the active portion 12A.

A vibration detection element includes substrates, support members, and an oscillator, and may be used as a biosensor and/or for liquid inspection by analysis of oscillator resonant frequency change. The substrates have a space portion, and the support members protrude from the surfaces of the respective substrates into the space portion. The oscillator is disposed between the support members and is capable of vibrating in the space portion. The support members may each include multiple supports which prevent the oscillator from contacting the substrate surfaces. During manufacturing the oscillator may be transferred from the support member of a glass flow path substrate to a silicon flow path substrate by placement of the silicon substrate support member against the oscillator and subsequent removal of the adhesive from the glass substrate support member.

A piezoelectric element includes a plurality of vibration regions that are separated from each other by a slit, and the slit is formed to have a tapered portion that is tapered from a first surface of the vibration regions on an opposite side to a support to a second surface opposite to the first surface. An electrode film is positioned inside than the slit when being viewed from a normal direction orthogonal to the first surface, and an angle formed by a side surface of the tapered portion in the vibration region and a surface parallel to the first surface is in a range of 39 to 81 degrees.

A piezoelectric element includes a plurality of vibration regions that are separated from each other by a slit, and the slit is formed to have a tapered portion that is tapered from a first surface of the vibration regions on an opposite side to a support to a second surface opposite to the first surface. An electrode film is positioned inside than the slit when being viewed from a normal direction orthogonal to the first surface, and an angle formed by a side surface of the tapered portion in the vibration region and a surface parallel to the first surface is in a range of 39 to 81 degrees.

A sensor for obtaining downhole data includes a first piezoelectric layer. The sensor also includes a second piezoelectric layer having a trench extending a depth below a surface of the second piezoelectric layer. The sensor also includes an electrode positioned within the trench. The first piezoelectric layer is directly coupled to the second piezoelectric layer.