KR102029559B1 - A piezoelectric element, method for manufacturing the same, a piezoelectric sensor and method for manufacturing with thereof - Google Patents

Abstract

Ultrasonic piezoelectric element manufacturing method according to an embodiment of the present invention, by processing the substrate, to obtain a mold 100 having a plurality of holes (100d) formed from one side 101 toward the other side (102) In the first step, the piezoelectric material 151 is supplied toward one side 101 of the mold 100 so that the piezoelectric material 151 flows into each hole constituting the plurality of holes 100d. Step 2, forming a pressure gradient such that the pressure in the first space V1 in which the other side surface 102 of the mold 100 is disposed is smaller than the pressure in the second space 100d forming the respective holes. A third step and a fourth step of sintering the piezoelectric material 151 filled in the plurality of holes (100d).

Description

Ultrasonic piezoelectric element, method for manufacturing ultrasonic piezoelectric element, ultrasonic piezoelectric sensor and method for manufacturing ultrasonic piezoelectric sensor {A piezoelectric element, method for manufacturing the same, a piezoelectric sensor and method for manufacturing with

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an ultrasonic piezoelectric sensor used in an ultrasonic fingerprint recognition sensor. In manufacturing a piezoelectric rod through a molding method using a powdered piezoelectric material, a material in a mold, in particular, By remarkably reducing the defective rate of the piezoelectric rod due to this filled state, the present invention relates to a method for producing an ultrasonic piezoelectric sensor with improved production yield and manufacturing process efficiency, and an ultrasonic piezoelectric sensor manufactured accordingly.

In general, ultrasonic waves refer to sound waves (about 20 to 1000 kHz) that humans cannot hear by hearing because their frequency is greater than about 20 kHz, which is the range of human audible frequencies. Because of the high frequency and the short wavelength, the vibration is quite strong, and thus has a short pulse characteristic with the directivity not found in general sound waves.

The ultrasonic sensor using the characteristics of the ultrasonic waves, and generates the ultrasonic wave to the outside, and the ultrasonic wave generated in this way receives a reflected wave returned by hitting the object to detect the distance to the sensing object or the movement, form or shape of the sensing object. It is used as a low sound pressure detection sensor to detect or used for high sound pressure in ultrasonic welding machines and ultrasonic cleaners.

In general, the ultrasonic sensor is largely composed of an ultrasonic transceiver, a driver, and a mechanical part. The ultrasonic transceiver unit receives an AC voltage from the driver to generate an ultrasonic wave, and receives the reflected wave returned in response to the generated ultrasonic wave to transmit the ultrasonic wave. The main components of the transmitting and receiving unit of the ultrasonic wave are a substrate and a piezoelectric element.

When an alternating current is applied to the piezoelectric element due to the current applied to the substrate, a crystal (piezoelectric material) generates a reverse piezoelectric force in which mechanical vibration is generated by repeating compression and expansion. For example, when an external force is applied to the piezoelectric element and contraction and expansion are repeated, positive charge is generated on one side of the piezoelectric element 150 and negative charge is generated on the other side to generate a current.

When ultrasonic waves are generated by the ultrasonic sensor, an alternating current is applied to the piezoelectric element from the outside, so that the piezoelectric element contracts and expands. The vibration generated by this is transmitted to the cover substrate, the vibration of the cover substrate generates a small wave in the air to generate the ultrasonic wave to the outside.

On the contrary, when the ultrasonic wave generated by the ultrasonic sensor is reflected back to the object, a small wave in the air is transmitted to the cover substrate to generate a displacement, and the reflected wave may be received by the contraction and expansion of the piezoelectric element due to the displacement.

Ultrasonic sensors that detect the distance to the object to be detected or the movement, form, or shape of the object by using such ultrasonic waves are widely used in various fields, and among them, portable or personal to maintain reliable security of personal information. In-situ where information is needed, it is used in security systems that detect and decode specific signals for identification of individual identities. Among them, it can be used for devices that recognize and authenticate individual biometric information.

For example, the ultrasonic sensor as described above may be used for personal authentication by recognizing a fingerprint in biometric information. In the case of such an ultrasonic fingerprint recognition sensor, an ultrasonic signal of a predetermined frequency emitted from a plurality of piezoelectric sensors may be a bone of a fingerprint ( When the reflection is reflected from the valley and the ridge, the difference in acoustic impedance between each valley and the ridge is measured by using a plurality of piezoelectric sensors, which are ultrasonic sources, to detect fingerprints. In addition, since the ultrasonic wave is generated in a pulse form and detects the Doppler effect caused by the echo wave, it has a function to grasp the blood flow inside the finger.

In the case of such an ultrasonic sensor, an ultrasonic signal reflected through an ultrasonic signal of a predetermined frequency generated through vibration of a plurality of piezoelectric materials is detected to recognize an object, so the signal of the reflected ultrasonic wave is low in noise, and the intensity of the reflected wave is constant. It should be ideal. Various studies have been conducted to improve the signal strength of the reflected wave.

Korean Laid-Open Patent No. 2016-0067549 (Published June 14, 2016)

The present invention is to produce a piezoelectric rod through the injection-pressing process using a powdered piezoelectric material in order to improve the production yield of the piezoelectric sensor, thereby significantly reducing the defective rate of the manufactured piezoelectric rod to improve the quality of the piezoelectric sensor manufacturing method And to provide a piezoelectric sensor manufactured according to this, and an ultrasonic sensor comprising the same.

Ultrasonic piezoelectric element manufacturing method according to an embodiment of the present invention, by processing the substrate, to obtain a mold 100 having a plurality of holes (100d) formed from one side 101 toward the other side (102) In the first step, the piezoelectric material 151 is supplied toward one side 101 of the mold 100 so that the piezoelectric material 151 flows into each hole constituting the plurality of holes 100d. Step 2, forming a pressure gradient such that the pressure in the first space V1 in which the other side surface 102 of the mold 100 is disposed is smaller than the pressure in the second space 100d forming the respective holes. A third step and a fourth step of sintering the piezoelectric material 151 filled in the plurality of holes (100d).

The first step of the ultrasonic piezoelectric element manufacturing method according to an embodiment of the present invention, the step of processing the substrate, forming a plurality of grooves (100f) embedded from the one side 101 and the plurality of grooves And forming a hole penetrating the bottom surface of each groove constituting 100f and the other side surface 102 of the mold 100.

The first step of the ultrasonic piezoelectric element manufacturing method according to an embodiment of the present invention,

Processing the substrate to form a plurality of holes 100e penetrating from the one side 101 to the other side 102 and to include respective holes constituting the plurality of holes 100e. It may include the step of forming a plurality of grooves recessed from the one side (101).

The second step and the third step of the ultrasonic piezoelectric element manufacturing method according to an embodiment of the present invention may be implemented at the same time.

The third step of the ultrasonic piezoelectric device manufacturing method according to an embodiment of the present invention, one side of the mold (100) by the pressing unit formed in a shape corresponding to the one side 101 of the mold (100) 101 may further comprise pressurizing.

In the third step of the ultrasonic piezoelectric device manufacturing method according to an embodiment of the present invention, the piezoelectric material introduced into the plurality of holes (100d) by pressing the mold 100 in a closed pressure reactor (10) The method may further include causing 151 to be dense.

The second step and the third step of the ultrasonic piezoelectric device manufacturing method according to an embodiment of the present invention may be repeated one or more times.

The ultrasonic piezoelectric element according to an embodiment of the present invention may be manufactured by the ultrasonic piezoelectric element manufacturing method of the present invention.

Ultrasonic piezoelectric sensor manufacturing method according to an embodiment of the present invention comprises the steps of preparing an ultrasonic piezoelectric element, an etching step of etching the mold 100 so that the piezoelectric rod 155 protrudes, the insulating material in the portion etched through the etching step After filling the 120 and filling the insulating material 120, the surface of the piezoelectric rod 155 is etched until the side surface of the piezoelectric rod 155 is exposed, and then the lower side of the exposed piezoelectric rod is formed in a predetermined pattern. Forming an electrode 171, adhering the dummy substrate 110 to a surface on which the lower electrode 171 is formed, and removing the base portion 100b of the mold to which the dummy substrate 110 is bonded. The method may include forming an ultrasonic piezoelectric sensor array by forming the upper electrode 172 on the other side of the piezoelectric rod 155 in a predetermined pattern.

Ultrasonic piezoelectric sensor manufacturing method according to an embodiment of the present invention between the step of forming and etching the piezoelectric rod 155, etching the via region 131 on the edge portion (100a) of the mold and The method may further include manufacturing a conductive filler 132 by filling a conductive material in the via region 131.

In the method of manufacturing an ultrasonic piezoelectric sensor according to an exemplary embodiment of the present invention, after the manufacturing of the ultrasonic piezoelectric sensor array, a plurality of piezoelectric elements disposed in the same column on the ultrasonic piezoelectric sensor array may be simultaneously subjected to voltage using a semiconductor test probe. In addition, it may further include a polling treatment (Poling treatment) step.

Ultrasonic piezoelectric sensor manufacturing method according to an embodiment of the present invention can be manufactured by the ultrasonic piezoelectric sensor manufacturing method of the present invention.

Jig for manufacturing an ultrasonic piezoelectric element according to an embodiment of the present invention, each of the holes constituting the plurality of holes of the mold obtained by processing the substrate-a plurality of holes penetrating from one side to the other side is formed. To form a pressure gradient such that the pressure in the first space in which the other side of the mold is disposed is less than the pressure in the second space forming each hole so that the piezoelectric material supplied from the one side is filled in the hole. In the jig for manufacturing an ultrasonic piezoelectric element, the first side facing the other side of the mold, the first side facing the other side of the mold, is formed spaced apart a predetermined distance, A second surface connected to the suction part and penetrating through the first and second surfaces, and a suction force provided from the suction part is provided between the first surface and the other side of the mold; It may include a pressure regulator to be provided.

The pressure control unit of the jig for manufacturing an ultrasonic piezoelectric element according to an embodiment of the present invention, the first connection hole embedded from the first surface and the second connection hole embedded from the second surface is formed in communication, The first connection hole may be formed by branching from the second connection hole.

The first connection hole of the jig for manufacturing an ultrasonic piezoelectric element according to an embodiment of the present invention may be formed at a position corresponding to the formation position of each hole constituting the plurality of holes.

The first connection hole of the jig for manufacturing an ultrasonic piezoelectric element according to an embodiment of the present invention may be in communication with the plurality of holes while being formed continuously from the first surface.

The pressure control unit of the jig for manufacturing an ultrasonic piezoelectric element according to an embodiment of the present invention, further comprises a connection groove which is embedded from the first surface and communicates with the first connection hole, the connection groove, the plurality of It may be formed to include the formation position of each hole constituting the hole.

The size of the longitudinal cross-sectional area of the second connecting hole of the jig for manufacturing an ultrasonic piezoelectric device according to an embodiment of the present invention may be larger than the cross-sectional area of the first connecting hole.

According to the present invention, by manufacturing a piezoelectric rod through a spray-pressing process using a powdered piezoelectric material, it is possible to manufacture a piezoelectric sensor with a significantly reduced defect rate of the manufactured piezoelectric rod, thereby improving production yield.

In addition, by forming the conductive filler in the piezoelectric sensor, it is possible to further energize the upper electrode and the lower electrode without wire bonding connecting the upper electrode and the lower electrode.

1 is a schematic diagram schematically showing a piezoelectric sensor according to an embodiment of the present invention.
2 is a schematic diagram schematically showing a piezoelectric sensor according to another embodiment of the present invention.
3A to 3F are schematic diagrams schematically illustrating a process of manufacturing the piezoelectric sensor of the present invention.
4 is a schematic diagram schematically showing a mold flattened through a planarization process after forming a conductive filler during the manufacturing process of the piezoelectric sensor of the present invention.
5 is a schematic diagram schematically showing a mold etched through an etching step in the manufacturing process of the piezoelectric sensor of the present invention.
6 to 8 are schematic views illustrating a planarized state in which a part of the insulating layer is removed by a planarization process before forming the lower electrode during the manufacturing process of the piezoelectric sensor of the present invention.
9 is a schematic diagram schematically showing a wafer manufactured according to another embodiment of the present invention.
10 is a schematic diagram schematically showing an ultrasonic sensor including a piezoelectric sensor formed on a substrate manufactured according to another embodiment of the present invention.
11 is a schematic view showing a jig for manufacturing an ultrasonic piezoelectric element according to an embodiment of the present invention.
12 is a schematic diagram illustrating a jig for manufacturing an ultrasonic piezoelectric element according to another exemplary embodiment of the present invention.

Before describing in detail through the preferred embodiments of the present invention, the terms or words used in the present specification and claims should not be construed as being limited to the conventional or dictionary meanings, meanings corresponding to the technical spirit of the present invention To be interpreted as

Throughout this specification, when a member is located in another member "top" or "bottom", this includes not only when one member is in contact with another member, but also when there is another member between the two members, " The upper part and the lower part may be changed from the upper part to the lower part and the lower part to the upper part according to the viewpoints defined as reference to the drawings.

When a part is said to be "connected" with another part, this includes not only the "directly connected" but also the indirectly connected with the other member in between.

In addition, it is to be understood that the drawings of the present specification are illustrated to enable those skilled in the art to easily understand and to practice the present invention.

Ultrasonic Piezoelectric Device Manufacturing Method

The ultrasonic piezoelectric element according to an embodiment of the present invention relates to a piezoelectric element provided in an ultrasonic piezoelectric sensor to be described later.

In the ultrasonic piezoelectric device manufacturing method of the present invention, first, a process of obtaining a mold 100 may be performed by processing a substrate. The processing of the substrate may be implemented by etching a substrate such as a silicon substrate through a photolithography method.

The photolithography is a method of copying a desired circuit design by copying a shadow formed by irradiating light onto a substrate, called a mask formed of a metal pattern on a glass plate, onto a substrate. One way is.

Such a photolithography method includes a coating process for uniformly applying a photosensitive composition to a surface of a substrate, a soft baking process for evaporating a solvent from the applied photosensitive film to attach the photosensitive film to the surface of the substrate, and an ultraviolet ray. Light exposure, which transfers the pattern of the mask onto the photoresist by repeatedly exposing and reducing the circuit pattern on the mask repeatedly and sequentially using a light source such as a light source, and a difference in solubility according to photosensitization through exposure to the light source. Development process to selectively remove parts having different physical properties such as developer using developer, Hard baking process to adhere and fix the photoresist film remaining after development process on the substrate, and developed photoresist film Remaining after etching and etching process to etch a certain area according to the pattern of The strip process may be performed to remove the photosensitive film.

Such a photolithography method includes a coating process for uniformly applying a photosensitive composition to a surface of a substrate, a soft baking process for evaporating a solvent from the applied photosensitive film to attach the photosensitive film to the surface of the substrate, and an ultraviolet ray. Light exposure, which transfers the pattern of the mask onto the photoresist by repeatedly exposing and reducing the circuit pattern on the mask repeatedly and sequentially using a light source such as a light source and a difference in solubility according to photosensitization through exposure to the light source. Development process to selectively remove parts having different physical properties by using developer, Hard baking process to adhere and fix the remaining photoresist film on the substrate Remaining after etching and etching process to etch a certain area according to pattern It may proceed to the process such as a strip (Strip) to remove the photosensitive film.

The photoresist composition applied to the surface of the substrate in the coating process is a medium for transferring the circuit design of the mask disc onto the substrate through an exposure process, and the photosensitive composition changes in solubility in a developer when exposed to light of a specific wavelength. There is a characteristic. By using such a feature, a pattern having a desired shape may be formed on a substrate through an etching process of selectively removing portions exposed to light and portions not exposed to light during a photolithography development process.

For example, in the forming of the mold, first, a) a photo resist sheet is formed on the prepared substrate.

In this case, the substrate may be used as long as it is generally used in a semiconductor process. For example, a silicon single crystal substrate, a silicon-on-insulator (SOI) substrate, a germanium (Ge) substrate, and a gallium-phosphorus (Gallium-) substrate. Phosphorus substrate, Gallium-Arsenic substrate and the like can be used, but preferably a round silicon substrate can be used. The photoresist is a material having photosensitive characteristics, and may be used that is commonly used in photolithography.

As a method of forming the photoresist on the prepared substrate, one of a spin coating method, a spray coating method, and a dip coating method may be used. For example, in the case of using the spin coating method, after forming a photoresist on the substrate, the photoresist may be stably formed on the substrate by partially removing a solvent in the photoresist through a post applied bake (PAB).

Next, b) photoresist is removed according to the pattern through the exposure / development process. That is, the photoresist may be concentrated by arranging a glass substrate having a mask pattern of a predetermined shape on the substrate to remove the photoresist in the region without the mask pattern. At this time, the photoresist in the region without the mask pattern is removed by the exposure / development process, and the photoresist in the region in which the mask pattern exists is left on the substrate.

On the contrary, panning may be performed by removing the photoresist in the region in which the mask pattern exists according to the type of photoresist.

C) A groove is formed in the portion where the photoresist of the portion formed on the substrate through the exposure / development process is removed through the etching process. The etching process may be generally divided into a wet etching method and a dry etching method.

In general, the wet etching method may chemically react with the surface of the portion of the photoresist on the substrate by using a chemical solution, thereby forming a groove on the substrate. Since the wet etching method is generally isotropic etching, undercut occurs and it is difficult to form an accurate pattern. In addition, process control is difficult, the line width that can be etched is limited, and additionally, it is difficult to process the generated etching solution.

Thus, dry etching is mainly used to compensate for the shortcomings of the wet etching method.

In general, the dry etching method may inject a reaction gas into a vacuum chamber, and then apply power to form a plasma. This may be used to chemically or physically react with the surface of the substrate to etch the portion of the photoresist removed on the substrate.

The dry etching method may be anisotropic etching, and the process may be easily controlled and an accurate pattern may be formed. In the present invention, the etching process may be performed through a dry etching method.

When the groove is formed in the substrate through the etching process, the photoresist remaining on the substrate may be completely removed to form a mold.

The mold 100 manufactured by forming the mold as described above includes a base 100b which is a bottom portion, a plurality of holes 100d formed by etching, and a pillar portion 100c which is a portion between the hole and the hole, except for the pillar portion. It may include the edge portion 100a that is the remaining portion of the mold.

Next, a second step of supplying the piezoelectric material 151 toward one side 101 of the mold 100 may be performed so that the piezoelectric material 151 flows into each hole constituting the plurality of holes 100d. have.

In the present specification, although the piezoelectric rod 155 is formed in the shape of a square pillar by forming the horizontal cross sections of the plurality of holes in a quadrangular shape, the horizontal cross sections of the plurality of holes are rectangular, circular, trapezoidal, rhombus, polygonal, etc. Is not particularly limited and may be formed in a variety of forms, the piezoelectric rod produced through this can also be formed in a horizontal cross-section of various forms in the form of a column.

Referring to FIG. 3A, the plurality of holes 100d to be formed through the first step may include a groove in which the piezoelectric material 151 is filled to form the piezoelectric rod 155 and communicate with the groove of the piezoelectric material 151. It may be formed as a hole to facilitate the filling into the groove. Here, the plurality of holes 100d may be formed by two methods.

First, the substrate is processed to form a plurality of grooves f recessed from one side 101 of the mold 100 and a bottom surface of each groove constituting the plurality of grooves 100f and the mold 100. It may be implemented through the step of forming a hole having a cross-sectional area smaller than the cross-sectional area of the plurality of grooves (100f), but penetrates the other side 102 of.

Briefly, the plurality of holes 100d may be implemented by first forming grooves and forming holes communicating with the grooves.

Second, the substrate is processed to form a plurality of holes 100e penetrating from one side 101 to the other side 102 of the mold 100, and each hole constituting the plurality of holes 100e. It may be implemented through the step of forming a plurality of grooves embedded from one side 101 to be included.

Briefly, the plurality of holes 100d may be implemented by first forming a hole and forming a groove communicating with the hole.

The above-described first step has been described under the assumption that the grooves forming the plurality of holes 100d and the sizes of the holes are different. However, when the sizes of the plurality of holes are formed in the same cross-sectional area, one side 101 of the mold 100 is formed. Of course, a plurality of holes may be formed by a single etching process of forming holes from the side toward the other side 102.

Meanwhile, in the second step, the piezoelectric material 151 is supplied toward one side 101 of the mold 100 so that the piezoelectric material 151 flows into each hole constituting the plurality of holes 100d. It may be a step.

Referring to FIG. 3B, the second step may be to fill the piezoelectric material 151 in the plurality of holes 100d by spraying the piezoelectric material 151 on the mold 100.

Specifically, the second step is to fill the piezoelectric material 151 in the plurality of holes by spraying the powdered piezoelectric material on the mold 100, preferably pulverized and powdered to a particle size of 10 ~ 100 ㎛ The piezoelectric material may be dry sprayed with a spray gun at a pressure of 1 to 5 MPa to fill the plurality of holes with the piezoelectric material.

At this time, the piezoelectric material 151 used is a PZT (PbZrO3) compound, a PST (Pb (Sc, Ta) O3 compound, quartz, (Pb, Sm) TiO3 compound, PMN (Pb (MgNb) O3-PT At least one selected from the group consisting of a (PbTiO 3) -based compound, a polyvinyllidene fluoride (PVDF) -based compound, and a PVDF-TrFe-based compound may be used.

In the second step, the piezoelectric material 151 powdered and ground to a particle size of 10 to 100 μm may be used, and when the particle size of the powdered piezoelectric material is less than 10 μm, it is too fine to spray sporadically during dry spraying. It can be stacked in other parts besides the plurality of holes, which can waste the material, and a lot of energy is consumed in the crushing, which can lower the economic efficiency, and when the particle size of the powdered piezoelectric material exceeds 100 μm, Spaces may be formed therebetween to form air vents, bubbles, and air gaps in the piezoelectric rod.

More preferably, during the dry spraying of the piezoelectric material powdered in the second step, the mold may be heated to a temperature of 500 ~ 700 ℃. As such, when the mold is heated in the second step, air formed between the piezoelectric materials that are dry sprayed and accumulated in the plurality of holes is reduced, and thus, the piezoelectric materials may be densely packed and stacked more densely.

The piezoelectric rod 155 may be included in an ultrasonic piezoelectric sensor to be described later to generate and receive ultrasonic waves when a voltage is applied.

Specifically, when an AC voltage having a resonant frequency of the ultrasonic band in which the piezoelectric material is vibrated is applied to the piezoelectric rod in the piezoelectric sensor, the piezoelectric rod may vibrate up and down and left and right, and thus the piezoelectric rod vibrates up and down and left and right. In this case, an ultrasonic signal having a predetermined frequency may be generated.

Therefore, in order to generate and receive ultrasonic waves by applying voltage to the piezoelectric sensor to accurately recognize the object, the piezoelectric material in the piezoelectric rod must be densely formed, and the shape of the piezoelectric rod to be manufactured must be undamaged and complete. For this purpose, holes, voids, air vents, bubbles, air gaps, etc., should not be formed in the piezoelectric rod.

For example, in order to form the piezoelectric rod 155 in the piezoelectric sensor, an insulating film may be deposited on a mold in which a plurality of holes are formed, and then a piezoelectric material may be injected.

In this case, as the insulating film used, silicon dioxide, silicon nitride, dialuminum trioxide, or the like may be used. The insulating film deposition method may be formed by depositing through physical vapor deposition or chemical vapor deposition. On the other hand, as the physical vapor deposition method, for example, sputtering or electron beam deposition.

After depositing an insulating film in the mold, a method of injecting a piezoelectric material may be injected into the piezoelectric material and pressurized using a flat pressing plate from above to inject gaps in the etched portion, for example, such as Jenopik's HEX04. Hot embossing equipment can be used to inject the piezoelectric material, which does not mean that the method of injecting the piezoelectric material is known.

However, when piezoelectric rods are manufactured by injecting piezoelectric materials using a pressure plate, the piezoelectric materials are not sufficiently homogeneously and densely injected into the respective holes, which causes holes, voids, and air vents between the filled piezoelectric materials. , Bubbles, and air gaps may be formed to form defective piezoelectric rods.

Accordingly, in the present invention, in order to solve such a problem, the piezoelectric material is powdered, sprayed onto the mold 100 in the form of fine particles, and the pressure in the plurality of holes 100d filled with the piezoelectric material is changed, The piezoelectric material 151 may be densely packed in the hole 100d.

As such, the pressure change in the plurality of holes 100d may be implemented in the third step.

Specifically, in the third step, the pressure gradient is such that the pressure in the first space V1 in which the other side surface 102 of the mold 100 is disposed is smaller than the pressure in the second space 100d forming the respective holes. It may be a step of forming. The third step includes a plurality of grooves while the piezoelectric material 151 introduced from one side 101 of the mold 100 moves from the second space 100d toward the first space V1 according to the pressure gradient. The filling of the plurality of holes 100d along 100f may be performed.

In the above-described second step, the piezoelectric material 151 is injected toward one side 101 of the mold 100, and the third step is a jig for manufacturing an ultrasonic piezoelectric element installed on the other side 102 of the mold 100. It can be implemented by. A jig (hereinafter, jig) for manufacturing the ultrasonic piezoelectric element will be described in detail with reference to FIGS. 11 and 12.

The other side 102 of the mold 100 is surrounded by a jig, causing a pressure change of the plurality of holes 100d formed in the mold 100 according to the pressure change of the space V1 formed between the jig. can do.

Specifically, when the pressure of the first space V1 is lowered by the jig, air in the space formed by the plurality of holes 100d is moved toward the jig, and at this time, one side 101 of the mold 100 is moved. The piezoelectric material 151 supplied thereto may be moved toward the plurality of holes 100d according to the pressure gradient formed by the jig and filled in the plurality of holes 100d.

For example, the first space V1 may be in a vacuum state by a jig to form a pressure gradient with the plurality of holes 100d in the atmospheric pressure state. Here, the jig may be implemented so that the pressure of the first space V1 is smaller than the pressure of the space formed by the plurality of holes 100d, and thus the pressure gradient of the present invention is not limited to being implemented through a vacuum state.

In addition, the cross-sectional area of the space for forming the piezoelectric rod 155 thereafter among the plurality of holes 100d is larger than the cross-sectional area of the hole formed in the base 100b to be removed later, so that all of the piezoelectric material 151 is formed through the hole. Make it difficult to pass. In other words, the piezoelectric material 151 may be filled so that there are no empty spaces in the plurality of holes 100d.

In the ultrasonic piezoelectric device manufacturing method according to an embodiment of the present invention, the second step and the third step may be implemented at the same time.

Specifically, the pressure of the first space V1 in which the piezoelectric material 151 is supplied toward one side 101 of the mold 100 and the other side 102 of the mold 100 is disposed, A pressure gradient may be formed to be smaller than the pressure of the second space 100d forming the hole, so that the piezoelectric material 151 may be introduced / filled into each hole constituting the plurality of holes 100d.

In the third step of the ultrasonic piezoelectric element manufacturing method according to an embodiment of the present invention, the one side 101 of the mold 100 by the pressing unit formed in a shape corresponding to the one side 101 of the mold 100 The method may further include pressurizing.

Specifically, the piezoelectric material 151 introduced into the plurality of holes 100d of the mold 100 may be located on the plurality of holes 100d and one side 101 of the mold 100. The pressurizing portion presses the one side 101 while being in contact with one side 101 to force the positional movement of the piezoelectric material 151 to the plurality of holes 100 and at the same time the piezoelectrics introduced into the plurality of holes 100d. The material 151 may be densely packed. Here, the pressing unit may be a kind of press.

The third step of the ultrasonic piezoelectric device manufacturing method according to an embodiment of the present invention is to press the mold 100 in the closed pressure reactor 10 to the piezoelectric material 151 introduced into the plurality of holes (100d). The method may further include a step of causing the density.

Specifically, a pressure of about 3 to 20 MPa is applied in the pressurized reactor 10 under an inert atmosphere of air and / or nitrogen gas to densely fill the piezoelectric materials filled in the plurality of holes, and between the filled piezoelectric materials. The formed air may be removed to remove air vents, bubbles, or air gaps.

In addition, the density of the piezoelectric material filled in the plurality of holes may be improved by condensing the piezoelectric materials filled in the plurality of holes, thereby shrinking the piezoelectric rod in the fourth step (sintering step) of a subsequent process. By reducing and minimizing the phenomenon, the defective rate of the piezoelectric rod can be significantly lowered.

Preferably, in the pressing step, 3 to 20 MPa pressure may be applied to the mold. When the pressure in the pressing step is less than 3 MPa, the pressure is not sufficient, so that the piezoelectric material filled in the holes is not sufficiently dense and the pores inside the piezoelectric rod ( Air vents, bubbles, or air gaps may be formed, and if the pressure exceeds 20 MPa, there is no benefit from pressurization, which may lower economic efficiency.

The second and third steps may be performed at least once or more times until the plurality of holes 100d in the mold 100 are completely filled with the piezoelectric material 151.

If the plurality of holes 100d are not completely filled with the piezoelectric material 151, the piezoelectric rod may not have a desired shape, and ultrasonic generation or reception may become unstable when a voltage is applied to the piezoelectric rod. Since the production yield of the resin may be reduced, it is preferable to repeatedly perform the second and third steps so that the piezoelectric material 151 may be completely filled in the plurality of holes in the mold.

When the piezoelectric material 151 is completely filled in the plurality of holes 100d in the mold 100, the piezoelectric material is heated through a fourth step (sintering step) of heating the mold 100 to sinter the piezoelectric material 151. The rod 155 may be formed.

This fourth step (sintering step) is for heating the piezoelectric material filled in the plurality of holes to a temperature range of the sintering point of the piezoelectric material to cause bonding between the particles of the piezoelectric material to solidify.

For example, when PZT (PbZrO3) is used as the piezoelectric material, in the sintering step, the PZT-filled mold may be heated at a temperature of 850 to 1,000 ° C. for 15 to 40 minutes to sinter PZT to manufacture a piezoelectric rod.

In particular, in the present invention, when the piezoelectric rod is formed, the piezoelectric material is powdered to densely fill the piezoelectric material in the plurality of holes through the second and third steps, thereby being used in the fourth step (sintering step). The piezoelectric material may be sintered at a temperature lower than the sintering point of the piezoelectric material.

As mentioned above, when PZT is used as a piezoelectric material, the sintering point of PZT is generally known to be about 1,200 ° C., but PZT is heated at a lower temperature of 850 to 1,000 ° C. for 15 to 40 minutes in the sintering step of the present invention. Sintering can produce a piezoelectric rod.

This minimizes the reaction between the silicon compound forming the mold and the piezoelectric material filled in the plurality of holes, and can be sintered at a temperature lower than the sintering point of the relatively filled piezoelectric material, thereby reducing energy consumption and improving economic efficiency. .

Meanwhile, in the present invention, after manufacturing the piezoelectric rod to connect circuit patterns formed on different layers in the piezoelectric sensor, the via region 131 is etched to the edge portion 100a of the mold as shown in FIG. 3C. The method may further include manufacturing a conductive filler 132 by filling a conductive material in the via region 131.

In order to connect circuit patterns formed in different layers in the piezoelectric sensor to each other, a hole called a via hole may be formed, and then a connection structure such as wire bonding may be formed through the via hole. However, the via hole formed through this method is not smooth in shape, and the substrate or the piezoelectric rod may be damaged due to the physical impact on the substrate or the mold during the formation of the via hole. This may lower the product yield and quality of the piezoelectric sensor.

Accordingly, in the present invention, before manufacturing the piezoelectric rod and then performing the etching step, the via region is etched in the edge portion 100a of the mold where the piezoelectric rod is not formed, and then the conductive material is formed in the via region. It may be filled to form a conductive filler. The conductive filler formed at this time may connect the lower electrode and the upper electrode which are manufactured in a subsequent process.

The via region is preferably a first via region 131 formed in a predetermined region of a side surface of a pattern in which a plurality of piezoelectric rods are formed as shown in FIG. 3C. Additionally, as shown in FIG. 8, the second via region may further include a second via region for forming a polling electrode for activating by applying a high voltage to the plurality of piezoelectric rods. The second-first via region 181a and the second-second via region 181b may be formed to face each other.

The method of etching the via region may be used without limitation as long as it is a method of etching resistive silicon or forming holes, but it is preferable to use the photolithography process used in the above-mentioned forming of the mold.

Specifically, the first via region 131 is formed to connect the upper electrode and the lower electrode in the manufactured piezoelectric sensor.

For example, when the pattern in which the plurality of piezoelectric rods are formed is a matrix, the first via region 131 may be formed as a predetermined region in a side portion of the column direction or the row direction in which the plurality of piezoelectric rods are arranged. Meanwhile, the second via regions 181a and 181b may be formed at positions facing each other on the outer portion of the mold so that a polling electrode for activating the piezoelectric rod may be formed.

The via region may be filled with a conductive material to form the conductive filler 132. In this case, the conductive materials used in the semiconductor manufacturing process may be used without limitation, as long as the conductive materials are generally used. Preferably, metallic materials, silicon-based conductive materials, and carbon-based conductive materials may be used. The silicon-based conductive material may be used.

For example, the conductive filler 132 may be formed by filling a conductive material in a first via region formed in a side portion in a column direction in which a plurality of piezoelectric rods formed in a matrix are arranged.

Except for the necessary portion of the conductive filler 132 formed as described above, the remaining unnecessary portion may be removed together with the pillar portion 100c and the edge portion 100a of the mold through a photolithography process in an etching step.

The ultrasonic piezoelectric element according to the exemplary embodiment of the present invention may be manufactured through the first to fourth steps described above.

Ultrasonic Piezoelectric Sensor Manufacturing Method

Method for manufacturing an ultrasonic piezoelectric sensor according to an embodiment of the present invention, after preparing the ultrasonic piezoelectric element described above, may include an etching step of etching the mold 100 so that the piezoelectric rod 155 protrudes. .

As mentioned above, the piezoelectric rod 155 and the conductive filler 132 are formed in the mold, and then planarized to completely expose one side of the pillar part of the mold through an etching step (plananarization process) as shown in FIG. 3D. Can be.

The planarization process may be used without limitation as long as it is a method capable of etching and planarizing a surface of a semiconductor process, but preferably, a chemical mechanical planarization (CMP) method may be used.

For example, in the forming of the conductive filler 132, the conductive filler 132 is formed by filling a conductive material in a first via region formed in a side portion in a column direction in which a plurality of piezoelectric rods formed in a matrix are arranged. Next, as shown in FIG. 4, the planarization process may be performed such that one side of the pillar portion of the mold is completely exposed.

In the etching step, the portions to be etched (parts formed with pillars and edges, parts of unnecessary conductive fillers) and parts not to be etched (parts formed with piezoelectric rods, required conductive fillers) by patterning on the surface of the flattened mold As described above, the photoresist sheet may be formed, and then the portion to be etched may be removed through an exposure / development process, a baking process, an etching process, and a strip process.

For example, as shown in FIG. 4, the planarized mold may be etched through the planarization process to form the pillar portion 100c, the edge portion 100a of the mold, and the column or row line line on which the pillar portion is formed. By etching selected portions of the portions, the conductive pillars 132b having a rectangular shape may protrude from the base 100b of the mold.

On the other hand, by removing all the portions of the conductive filler formed on the column line or the row line line in which the pillar portion 100c in the mold is formed, the conductive pillar 132a having a square pillar shape like a piezoelectric rod as shown in FIG. 5. ) Can be formed.

This leaves only the portions of the piezoelectric rod 155 and the necessary conductive fillers 132a and 132b through the desired patterning during the etching process and removes the remaining portions, thereby remaining unetched with the piezoelectric rod 155 on the base phase 100b of the mold. The conductive fillers 132a and 132b may protrude from each other.

The non-etched conductive fillers 132a and 132b do not need to form a connection structure such as wire bonding in the piezoelectric element by connecting the lower electrode and the upper electrode formed in a subsequent process. In addition, since an additional process for forming a hole for such a connection structure is not necessary, physical damage can be prevented by minimizing an impact on the manufacturing process, thereby significantly improving the production yield of the piezoelectric sensor.

As in the third step of FIG. 3d, the insulating material 120 is filled in a portion of the pillar part 100c, the edge part 100d, and / or the conductive filler etched through the etching step. As shown in FIG. 7, a mold in which the piezoelectric rod 155 and the conductive fillers 132a and 132b are formed between the insulating materials 120 may be manufactured.

When the piezoelectric sensor operates as a sensor, when the AC current is applied to the piezoelectric rod and vibrates up and down, the insulating material 120 is disposed between the piezoelectric rod and the piezoelectric rod so that ultrasonic waves do not affect each other. By isolating and attenuating the high ultrasonic signal, the signal noise and sensitivity of the sensor can be optimized. Preferably, the insulating material can be used without limitation as long as it is a material for insulating a current, preferably an epoxy resin can be used.

Preferably, as shown in FIGS. 6 to 8, the insulating material 120 in the mold may be filled, and then may be etched and planarized through a planarization process until one side of the shielded piezoelectric rod and the conductive filler is completely exposed.

Specifically, in the case of FIG. 6 or FIG. 7, as described above, the conductive filler formed in the first via region is etched, so that the conductive pillar 132a having a rectangular pillar shape and the conductive filler 132b having a rectangular shape are respectively formed. After forming, an example is shown in which the insulating material is filled in the etched portion.

In addition, in the case of FIG. 8, second via regions 181a and 181b are formed at positions facing each other on the outer portion of the mold to form a polling electrode, and a conductive filler is filled in the second via regions. An example in which the insulating material 120 is filled in form is shown.

6 to 8 illustrate some of the various examples of the piezoelectric rod and the conductive filler formed in the mold of the present invention, and can be appropriately adjusted through preferred patterning according to various embodiments and usage of the piezoelectric sensor to be manufactured. There may be an embodiment.

As shown in FIG. 3E, the lower electrode 171 may be formed in a predetermined pattern on a surface exposed to one side of the piezoelectric rod 155.

In detail, the forming of the lower electrode 171 may include depositing a conductive material on one side of the exposed piezoelectric rod as shown in FIG. 3D and etching the conductive material in a predetermined pattern to form the lower electrode 171. It may include forming a lower electrode. In this case, any conductive material used may be used without limitation as long as it has conductive properties. For example, a compound including any one selected from the group consisting of copper, aluminum, gold, silver, nickel, tin, zinc, and alloys thereof Can be used.

For example, the forming of the lower electrode 171 may be performed by uniformly depositing a conductive material on a mold having one side of the piezoelectric rod exposed through planarization as shown in FIG. 3D by sputtering. A metal layer is formed. After the photoresist is applied to the formed metal layer, the photoresist is exposed to light according to a predetermined mask pattern to remove a portion of the photoresist, and then the metal layer of the portion of the photoresist removed is etched. 2) After etching, if all remaining photoresist is removed, the metal layer remaining without etching becomes the lower electrode 171. 3) after bonding the dummy substrate 110 to the mold by bonding the dummy substrate 110 to the surface of the mold 100 on which the lower electrode 171 is formed, the upper electrode 172 may be formed. It is preferable to invert the mold.

Removing the base portion 100b of the mold to which the dummy substrate is bonded to form the upper electrode 172 in a predetermined pattern on the other side of the exposed piezoelectric rod to manufacture the piezoelectric sensor array, as shown in FIG. 3E. 2) the base portion of the inverted mold is removed and planarized to expose the other side of the piezoelectric rod 155, and then 2) a conductive material is uniformly deposited through a sputtering process to form a metal layer. As described above, the piezoelectric sensor array shown in FIG. 7 may be manufactured by etching the portion of the metal layer to form the upper electrode 172 by using the photolithography method as in the method of forming the lower electrode. In this case, the upper electrode 172 is preferably formed in a direction perpendicular to the lower electrode 171.

In the piezoelectric sensor array manufactured by manufacturing the piezoelectric sensor array as described above, the plurality of piezoelectric elements 155 may be arranged in a matrix form. In this case, in order for the plurality of piezoelectric elements included in the piezoelectric sensor array to have a function of the sensor, the piezoelectric rod in the piezoelectric element should be activated by applying a high voltage to the piezoelectric material through a polling process.

In order to activate the piezoelectric rod, the piezoelectric rod was activated by applying a high voltage to each piezoelectric element, but even though each piezoelectric rod was polarized under the same conditions (voltage, time, etc.), the piezoelectric rods were slightly different. Can be.

Therefore, in the present invention, after the step of manufacturing the piezoelectric sensor array to reduce such a difference, a polling step of applying a voltage at the same time by using a semiconductor test probe to a plurality of piezoelectric elements arranged in the same column; It may further comprise a piezoelectric element.

In this case, the semiconductor test probe may be used to simultaneously apply voltage to each of the conductive fillers in the piezoelectric elements arranged in the same column, the first polling electrode and the second polling electrode, or the piezoelectric rods arranged in the same column.

On the other hand, when a voltage is applied to the conductive filler formed through the second via regions 181a and 181b and the second falling electrode 191, the conductive filler formed on the second via region is connected to the lower electrode. The second falling electrode is connected to the upper electrode, so that the piezoelectric element can be activated by applying a voltage to all of the piezoelectric rods.

As another method, a lower polling electrode connected to the lower electrode may be formed at a position corresponding to the second via regions 181a and 181b and exposed to the outside to upper polling corresponding to the second polling electrodes 191a and 191b. The piezoelectric element may be activated by connecting a voltage through an electrode and a wire.

When the piezoelectric element is activated through the polling step, the piezoelectric sensor 200 may be manufactured by cutting the wafer on which the plurality of piezoelectric elements are formed, into each piezoelectric element through a dicing step.

Although the piezoelectric element is separated through the dicing step, an unnecessary dummy substrate 110 is attached to the piezoelectric element with an adhesive. Therefore, the piezoelectric sensor 200 may be manufactured by separating the dummy substrate 110 and the piezoelectric element by applying heat at a temperature at which the adhesive may be melted.

Another embodiment of the present invention is a piezoelectric sensor manufactured by the aforementioned manufacturing method, it is possible to manufacture an ultrasonic sensor using such a piezoelectric sensor 200.

By forming the piezoelectric sensor 200 on the substrate 210, an ultrasonic sensor may be manufactured.

The substrate 210 is a plate formed by arranging a plurality of piezoelectric sensors, and may be manufactured using an insulating material capable of forming a conductor pattern on the surface of the insulating substrate. The substrate is not particularly limited as long as it is usually used for a circuit board, and can be used. Preferably, a printed circuit board (PCB) can be used.

Preferably, the substrate 210 may have a cavity 215 formed under a portion where the plurality of piezoelectric sensors 200 are formed, as shown in FIG. 8. The ultrasonic sensor is a piezoelectric rod is applied to the piezoelectric sensor 200 by applying a current to generate ultrasonic waves through the vertical vibration, the amplitude of the ultrasonic wave generated by the cavity formed in the lower portion of the piezoelectric sensor to improve the reflection of the reflected object By amplifying the signal strength of the returned reflected wave, accurate and reliable information can be obtained.

The arrangement of the plurality of piezoelectric sensors formed on the substrate may have various arrangements of piezoelectric sensors depending on the pattern, shape, and shape of the electrodes on the substrate, and the same arrangement according to the arrangement of the piezoelectric sensors. The cavity may be formed at the bottom of each piezoelectric sensor.

The shape of the cavity may be a groove such as a pillar, an horn, etc. having a horizontal cross section having various horizontal cross sections such as polygonal, circular or oval shape.

In addition, at least one or more of an inner line of the horizontal cross section of the piezoelectric sensor may be formed longer than an inner line of the horizontal cross section of the cavity formed on the same line so that the piezoelectric sensor formed on the cavity may be formed on the substrate. In this case, the internal line segment refers to a line segment connecting a point on the edge of the cross section passing through the center of gravity (G) of the cross section.

Preferably, the horizontal cross-sectional shape of the cavity is formed in the shape of a cross, but the width of the cross-crossing area may be smaller than the width of the horizontal cross-section of the piezoelectric sensor formed thereon. This is because the corner portion of the piezoelectric sensor is bonded to the substrate not only to give a sense of stability, but also to increase the vibration of the piezoelectric sensor to amplify the signal strength of the generated ultrasonic waves.

For manufacturing ultrasonic piezoelectric elements Jig

A jig (hereinafter, jig) for manufacturing an ultrasonic piezoelectric element according to an embodiment of the present invention may be used for manufacturing the ultrasonic piezoelectric element described above.

The jig 300 is formed to be equal to or larger than the size of the other side 102 of the mold (see FIG. 3A), and is uniform with the first side 310 and the first side 310 facing the other side of the mold. The second surface 320 is disposed spaced apart from each other, and is connected to the suction part (not shown), the thickness forming part 330 connecting the first surface 310 and the second surface 320 and the first surface. The pressure regulating part is formed through the surface 310 and the second surface 320, and the suction force provided from the suction portion is provided between the first surface 310 and the other side surface 102 of the mold ( 340 may be included.

The pressure adjusting unit 340 may be formed by communicating the first connection hole 342 embedded in the first surface 310 and the second connection hole 341 embedded in the second surface 320. .

The first connection hole 342 may be disposed in parallel with the plurality of holes formed in the mold, such that air remaining in the plurality of holes may move to the second connection hole 341.

The pressure regulator 340, while connected to the suction unit, may provide a passage for allowing air between the first surface 310 and the other side 102 of the mold to move to the suction unit according to a pressure gradient provided through the suction unit. Can be.

The first connection hole 342 may be formed by branching from the second connection hole 341.

In addition, referring to FIG. 11, the pressure adjusting unit 340 may further include a connection groove 350 recessed from the first surface 310 to communicate with the first connection hole 342.

Here, the connection groove 350 may be formed to include the formation position of each hole constituting the plurality of holes.

12, the jig 400 according to another embodiment of the present invention includes a first surface 410, a second surface 420, a thickness forming unit 430, and a pressure adjusting unit 440. The first connection hole 442 may be formed at a position corresponding to the formation position of each hole constituting the plurality of holes. The first connection hole 442 may be formed by branching the second connection hole 441.

The pressure adjusting unit 440 of the jig 400 may also allow the suction force provided from the suction unit to be provided between the first side 410 and the other side 102 of the mold as described above.

In FIG. 12, although the first connection hole 442 is formed at a position corresponding to the formation position of each hole constituting the plurality of holes, it is shown that each connection hole is spaced apart from the first surface 410. Of course, it can be in communication with the plurality of holes while being formed continuously from.

On the other hand, the longitudinal cross-sectional area of the second connecting hole may be formed larger than the size of the longitudinal cross section of the first connecting hole. This is to facilitate the inflow of air from the first connection hole formed by branching the second connection hole to the second connection hole so that the air flow between the first surface and the other side of the mold is smoothed by the pressure adjusting unit. .

The jig described with reference to FIGS. 11 and 12 is an embodiment of a jig used for manufacturing the ultrasonic piezoelectric element of the present invention, and the present invention is not limited thereto, and is connected to the other side of the mold to form a plurality of jigs. If the jig configuration that can flow out the air in the hole can be used for manufacturing the piezoelectric element of the present invention.

Accordingly, the position and the shape of the first connecting hole and the second connecting hole of the jig may be variously formed.

In the above description of the configuration and features of the present invention based on the embodiment according to the present invention, the present invention is not limited thereto, and various changes or modifications can be made within the spirit and scope of the present invention. It will be apparent to those skilled in the art that such changes or modifications fall within the scope of the appended claims.

10: pressurized reactor 100: mold
100a: edge of mold 100b: base of mold
100c: pillar portion of mold 100d: plurality of holes
110: dummy substrate 120: insulating material
131: via region 132: conductive filler
151: piezoelectric material 152: adhesive solution
155: piezoelectric rod
171: lower electrode 172: upper electrode
200: piezoelectric sensor 210: substrate
215: cavity

Claims (18)

In the method of manufacturing an ultrasonic piezoelectric element,
A first step of processing the substrate to obtain a mold 100 having a plurality of holes 100d penetrating from one side 101 to the other 102;
Supplying the piezoelectric material (151) toward one side (101) of the mold (100) so that the piezoelectric material (151) flows into each hole constituting the plurality of holes (100d);
A third step of forming a pressure gradient such that the pressure in the first space V1 in which the other side surface 102 of the mold 100 is disposed is smaller than the pressure in the second space 100d forming the respective holes. ; And
And a fourth step of sintering the piezoelectric material 151 filled in the plurality of holes 100d.
The first step,
Processing the substrate to form a plurality of grooves (100f) recessed from the one side (101); And
Penetrating the bottom surface of each groove constituting the plurality of grooves 100f and the other side surface 102 of the mold 100, and forming a hole having a cross-sectional area smaller than the cross-sectional areas of the plurality of grooves 100f. Including;
The third step,
When the piezoelectric material 151 introduced from one side 101 of the mold 100 moves from the second space 100d toward the first space V1 according to the pressure gradient, the plurality of grooves ( Ultrasonic piezoelectric element manufacturing method is filled in the plurality of holes (100d) along 100f).
delete The method of claim 1,
The first step,
Processing the substrate to form a plurality of holes (100e) penetrating from the one side (101) toward the other side (102); And
Forming a plurality of grooves recessed from the one side surface (101) so that each hole constituting the plurality of holes (100e) is included.
The method of claim 1,
And the second step and the third step are implemented at the same time.
The method of claim 1,
The third step,
Ultrasonic piezoelectric element manufacturing method further comprising the step of pressing the one side (101) of the mold (100) by the pressing unit formed in a shape corresponding to the one side (101) of the mold (100).
The method of claim 1,
The third step,
And pressurizing the mold (100) in a closed pressurized reactor (10) so that the piezoelectric material (151) introduced into the plurality of holes (100d) is concentrated.
The method of claim 1,
Ultrasonic piezoelectric element manufacturing method characterized in that the second step and the third step is repeated one or more times.
An ultrasonic piezoelectric element manufactured according to the ultrasonic piezoelectric element manufacturing method of claim 1.
Preparing an ultrasonic piezoelectric element manufactured according to the ultrasonic piezoelectric element manufacturing method of any one of claims 1 and 3;
Etching the mold 100 so that the piezoelectric rod 155 protrudes;
Filling the insulating material 120 in the portion etched through the etching step;
Etching until one side of the piezoelectric rod 155 covered by the insulating material 120 is exposed, and then forming a lower electrode 171 on a side of the exposed piezoelectric rod in a predetermined pattern. ;
Bonding the dummy substrate 110 to a surface on which the lower electrode 171 is formed; And
Manufacturing an ultrasonic piezoelectric sensor array by removing the base portion 100b of the mold to which the dummy substrate 110 is adhered to form an upper electrode 172 in a predetermined pattern on the other side of the exposed piezoelectric rod 155. Ultrasonic piezoelectric sensor manufacturing method comprising a.
The method of claim 9,
Between forming the piezoelectric rods 155 and etching,
Etching via regions (131) in edges (100a) of the mold; And
And manufacturing a conductive filler (132) by filling a conductive material in the via region (131).
The method of claim 9,
After manufacturing the ultrasonic piezoelectric sensor array,
And a polling step of applying a voltage to a plurality of piezoelectric elements disposed in the same column on the ultrasonic piezoelectric sensor array using a semiconductor test probe at the same time.
An ultrasonic piezoelectric sensor manufactured according to the manufacturing method of the ultrasonic piezoelectric sensor of claim 9.
Mold obtained by processing a substrate-a plurality of grooves formed from one side of the mold is formed, penetrating the bottom surface of each groove constituting the plurality of grooves and the other side of the mold, the plurality of grooves A hole having a cross-sectional area smaller than the cross-sectional area of-is formed, the pressure of the first space in which the other side of the mold is disposed so that the piezoelectric material supplied from the one side is filled in each hole of the plurality of holes of In the jig for manufacturing an ultrasonic piezoelectric element for forming a pressure gradient to be smaller than the pressure of the second space forming each hole,
A first surface facing the other side of the mold, the first side being formed to be larger than or larger than the size of the other side of the mold;
A second surface spaced apart from the first surface by a predetermined distance and connected to the suction part; And
It is formed through the first surface and the second surface, the pressure adjusting portion for allowing a suction force provided from the suction portion is provided between the first surface and the other side of the mold;
Piezoelectric material introduced from one side of the mold is jig for the ultrasonic piezoelectric element is filled in the plurality of holes along the plurality of grooves during the movement from the second space toward the first space in accordance with the pressure gradient.
The method of claim 13,
The pressure control unit,
The first connection hole embedded from the first surface and the second connection hole embedded from the second surface are formed in communication with each other,
The first connection hole,
Jig for manufacturing an ultrasonic piezoelectric element formed by branching from the second connection hole.
The method of claim 14,
The first connection hole,
A jig for manufacturing an ultrasonic piezoelectric element formed at a position corresponding to a position where each hole constituting the plurality of holes is formed.
The method of claim 14,
The first connection hole,
A jig for manufacturing an ultrasonic piezoelectric element communicating with the plurality of holes while being continuously formed from the first surface.
The method of claim 14,
The pressure control unit,
And a connection groove recessed from the first surface to communicate with the first connection hole.
The connecting groove,
Jig for manufacturing an ultrasonic piezoelectric element is formed to include the formation position of each hole constituting the plurality of holes.
The method of claim 14,
Longitudinal area of the second connecting hole,
Jig for manufacturing an ultrasonic piezoelectric element, characterized in that greater than the size of the longitudinal area of the first connection hole.

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