KR101622488B1 - The ultrasound array transducer manufactured by using inversion layer technique and method for manufacturing thereof - Google Patents

Abstract

The present invention relates to an array ultrasound transducer for diagnosis through a polarization inversion and the adjustment of a thickness ratio of multiple piezoelectric elements and a manufacturing method thereof, and more specifically, to an array ultrasound transducer which is manufactured to have each of a high frequency broadband characteristic and a multi- frequency harmonic wave characteristic by means of the inversion and thickness ratio adjustment of multiple piezoelectric elements. The transducer also has a basic frequency which is improved as much as 1.5 times compared with the frequency of a single piezoelectric element structure, and an improved -6dB bandwidth when the transducer has a high frequency broadband characteristic. Therefore, due to the characteristics, the transducer easily improves the resolution of ultrasound images. When having a multi-frequency harmonic wave characteristic, the transducer is useful to implement images of the ultrasound harmonic wave because the basic frequency component is identical with that of a single piezoelectric element structure and the harmonic wave frequency component is greatly improved. By means of a valley generated between the basic frequency and the harmonic wave frequency, a filter to extract only the harmonic wave frequencies can be easily applied. The present invention is manufactured to be selectively used to have the two characteristics of the high frequency broadband and the multi-frequency harmonic wave in one array ultrasound transducer by consecutively arranging each element having the aforementioned characteristics, such that a user selectively adjusts characteristics appropriated to the diagnosis purpose. Manufacturing such array ultrasound transducer minimizes the use of an accurate cutter and designs the method similarly to a manufacturing method of the existing ultrasound transducers, thereby preventing damage to piezoelectric elements, and reducing time and costs during the manufacturing process.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an array type ultrasonic transducer manufactured by using an inversion layer technique and a method of manufacturing the array type ultrasonic transducer,

The present invention relates to an array type ultrasonic transducer for diagnosis and a method of manufacturing the same, and more particularly, to a piezoelectric transducer for ultrasonic transducer, An array type ultrasound transducer for diagnosing an array type ultrasound transducer capable of simultaneously providing a high frequency broad bandwidth characteristic and a multiple frequency harmonic characteristic which is easy to implement a harmonic image and a method of manufacturing the same will be.

Generally, an ultrasound imaging system transmits ultrasound generated by an ultrasound transducer to the inside of the human body and implements diagnostic ultrasound imaging. In order to improve the resolution of the ultrasound image, the fundamental frequency of the ultrasound transducer must be increased or the ultrasound transducer must have a wide frequency band. Also, the resolution of the image can be improved by using the harmonic frequency component (mainly twice the fundamental frequency) generated by the nonlinearity of the human body. However, in order to increase the fundamental frequency, it is necessary to make the piezoelectric element thin, so that the manufacturing process is difficult. In general, piezoelectric elements such as PMN-PT and PZT-5H used in a diagnostic array-type ultrasonic transducer have a limitation in having a wide frequency band because their acoustic impedance values are very large. In order to lower the acoustic impedance, there is a method of changing the structure of the piezoelectric element so as to have a structure of 2-2 or 1-3 composite using a piezoelectric element and an epoxy, but also the manufacturing process becomes complicated And it is difficult to provide sufficient bandwidth to acquire harmonic images. In implementing a harmonic image, the frequency component that is about twice as high as the fundamental frequency should be included in the ultrasound transducer bandwidth to be used. However, due to the limited bandwidth, a frequency component about twice as high as the fundamental frequency component is included in the general ultrasound transducer structure And even if the image is implemented using such a harmonic component, the signal reception efficiency of the harmonic frequency component is low, so that it is difficult to implement and diagnose the ultrasonic image. In addition, when applying a filter for extracting only harmonic frequency components to implement ultrasonic harmonic image, it is difficult to extract only harmonic frequency components purely because various frequency components are included in the frequency range of harmonic frequency components.

As an embodiment of the present invention, a method for manufacturing an ultrasonic transducer for diagnostics having a device having a high-frequency broadband characteristic and a device having a multiple-frequency harmonic characteristic at the same time can be provided through polarization reversal and thickness ratio control of a multiple piezoelectric transducer. In an ultrasonic transducer according to an embodiment of the present invention, a device having a high-frequency broadband characteristic can have a basic frequency component that is about 1.5 times higher than that of a single piezoelectric device structure and can have a wide bandwidth at the same time. In the case of a device having multiple frequency harmonic characteristics, it is possible to have an improved amplitude at a harmonic frequency component compared to a single piezoelectric device structure, and to easily extract a harmonic frequency component using a bandwidth valley between a fundamental frequency and a harmonic frequency can do. According to the transformer manufacturing technique according to the embodiment of the present invention, these two characteristics can be easily implemented in one transformer. In the transducer structure according to an embodiment of the present invention, the elements having high frequency broadband and multi-frequency harmonic characteristics are sequentially arranged and manufactured as a single array type ultrasonic transducer for diagnosis, so that one ultrasonic transducer generates high frequency broadband Characteristics and multi-frequency harmonic characteristics can be selectively used, or both characteristics can be simultaneously used to improve the resolution of the ultrasound image.

As an embodiment of the present invention, an array type ultrasonic transducer manufactured using a reverse layer technique can be provided. The ultrasonic transducer according to an embodiment of the present invention can selectively or simultaneously exhibit high frequency broadband and multiple frequency harmonic characteristics through polarization reversal and thickness ratio control of the multiple piezoelectric elements.

The multiple piezoelectric elements included in the ultrasonic transducer may be the same piezoelectric element or different kinds of piezoelectric elements.

Ultrasonic transducers can be conjugated so that their polarities are opposite to each other in a multiple piezoelectric device structure for manufacturing devices having high frequency broadband and multi-frequency harmonic characteristics.

Ultrasonic transducers may have different thickness ratios for each element in a multiple piezoelectric element structure for fabricating devices with high frequency broadband and multiple frequency harmonic characteristics.

As another embodiment of the present invention, an array type ultrasonic transducer fabricated using a reverse layer technique can be provided. In order for the high frequency broadband characteristic and the multiple frequency harmonic characteristic to appear in the ultrasonic transducer, a device exhibiting a high frequency broadband characteristic and a device exhibiting a multiple frequency harmonic characteristic may be sequentially arranged.

The ultrasonic transducer can be interlocked with the cut spaces to sequentially arrange the elements having the high frequency optical bandwidth and the multiple frequency harmonic characteristic configured at different ratios.

The ultrasound transducer may include a single element transducer or an array transducer.

The fundamental frequency and bandwidth can be adjusted according to the material, thickness or shape of the sound-absorbing layer and the multiple matching layer included in the ultrasonic transducer.

It is possible to transmit and receive signals in any one of the high frequency broadband mode, the multiple frequency harmonic mode, and the combining mode based on the operation of the switch connectable with the ultrasonic transducer, and the combining mode is a mode combining high frequency broadband and multi frequency harmonic characteristics Lt; / RTI >

At least one element exhibiting a high-frequency broadband characteristic in the composite mode and at least one element exhibiting multi-frequency harmonic characteristics simultaneously are simultaneously driven, and the received signals are summed in an operation unit connectable with an ultrasonic transducer, Can be selectively normalized by the normalization unit.

As one embodiment of the present invention, a method for fabricating an array-type ultrasonic transducer using a reverse-layer technique can be provided. A method according to an embodiment of the present invention includes aligning the polarities of a first element and a second element available as multiple piezoelectric elements so as to be located in the same direction in which ultrasonic energy propagates, Cutting the surface of the first element and the second element so that the polar directions of the first element and the second element are opposite to each other; cutting the surface of the bonded element to produce a width (Kerf) Filling the fillet with the generated tooth width, and lapping the upper and lower surfaces of the bonded element to have a predetermined fundamental frequency component.

The at least one column shape according to an embodiment of the present invention may have the same width and the same height value, and may be formed at equal intervals with respect to the surface.

A method according to an embodiment of the present invention includes the steps of bonding an element bonded in advance to a signal line on a surface of a printed circuit board for applying a signal to a first element and a second element, Bonding the sound absorbing layer to the lower portion of the bonded element, and bonding at least one of the matching layers to the upper portion of the bonded element.

In the ultrasonic transducer according to an embodiment of the present invention, the device 220 having a high-frequency broadband characteristic may have a fundamental frequency component increased by about 1.5 times as much as a single piezoelectric device structure, and at the same time, have a wide bandwidth.

In addition, in the case of the device 230 having the multiple frequency harmonic characteristic, it is possible to have an improved amplitude at the harmonic frequency component with respect to the single piezoelectric device structure.

In addition, the harmonic frequency components can be easily extracted using the bandwidth valley between the fundamental frequency and the harmonic frequency.

In the transducer structure according to an embodiment of the present invention, the elements having high frequency broadband and multi-frequency harmonic characteristics are sequentially arranged and manufactured as a single array type ultrasonic transducer for diagnosis, so that one ultrasonic transducer generates high frequency broadband Characteristics and multi-frequency harmonic characteristics can be selectively used, or both characteristics can be simultaneously used to improve the resolution of the ultrasound image.

FIG. 1 shows a structure of a piezoelectric device having a high frequency broadband characteristic by controlling the polarization inversion and thickness ratio of a multiple piezoelectric device and a structure of a piezoelectric device having multiple frequency harmonic characteristics according to an embodiment of the present invention.
2 shows piezoelectric elements of various structures for verifying the performance of the piezoelectric element structure according to an embodiment of the present invention.
3 shows a simulation result of an FEM (finite element method) of the electrical impedance result according to the structure of the piezoelectric element.
4 shows FEM simulation results under various situations according to an embodiment of the present invention.
FIG. 5 illustrates a process of fabricating an ultrasonic transducer capable of simultaneously having a high-frequency broadband and a multi-frequency harmonic characteristic according to an embodiment of the present invention.
6 is a block diagram of an ultrasound system capable of acquiring an ultrasound image using an ultrasound transducer according to an embodiment of the present invention.

The terms used in this specification will be briefly described and the present invention will be described in detail.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. Also, in certain cases, there may be a term selected arbitrarily by the applicant, in which case the meaning thereof will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term, not on the name of a simple term, but on the entire contents of the present invention.

When an element is referred to as "including" an element throughout the specification, it is to be understood that the element may include other elements as well, without departing from the spirit or scope of the present invention. Also, the terms " part, "" module," and the like described in the specification mean units for processing at least one function or operation, which may be implemented in hardware or software or a combination of hardware and software .

The term "ultrasound image" in the entire specification means an image of a target object obtained by using the principle of scattering, reflection, and refraction of ultrasound.

Throughout the specification, the term "user" may be a physician, nurse, clinician, medical imaging expert, etc. as a medical professional and may be, but not limited to, a technician repairing a medical device.

Throughout the specification, "object" can include a portion of the body. For example, a subject may include organs such as the liver, heart, uterus, brain, breast, abdomen, and the like.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 shows a structure of a piezoelectric device 220 having a high-frequency broadband characteristic and a structure of a piezoelectric device 230 having multiple frequency harmonic characteristics by controlling the polarization inversion and thickness ratio of the multiple piezoelectric device according to an embodiment of the present invention .

The ultrasonic transducer according to the embodiment of the present invention may have a structure as shown in FIG. 1 (a) so as to have a high frequency broadband characteristic through the polarization inversion of the multiple piezoelectric elements and the thickness ratio control. Also, the ultrasonic transducer may have a structure of a piezoelectric element having multiple frequency harmonic characteristics as shown in FIG. 1 (b).

1, a piezoelectric device used for a structure having high frequency broadband and multiple frequency harmonic characteristics includes a piezoelectric device such as PMN-PT 100 and PZT-5H 110, Devices, and the positions of the PMN-PT 100 and the PZT-5H 110 may be varied from each other. Each piezoelectric element is manufactured by bonding the piezoelectric elements 120 so that the polarization directions 120 are opposite to each other, and can be classified into high frequency broadband and multiple frequency harmonic characteristics according to the thickness ratio of each piezoelectric element in the transducer laminate structure. In other words, when the total thickness of the piezoelectric device suitable for the fundamental frequency to be designed is set to t and the thickness of the polarization inversion layer is set to t ₁ , when the polarization inversion layer is located at the upper part where the ultrasonic energy advances, And may have multiple frequency harmonic characteristics when positioned at the bottom.

2 shows piezoelectric elements of various structures for verifying the performance of the piezoelectric element structure according to an embodiment of the present invention. FIG. 2 shows piezoelectric elements of various structures attempted at a comparative level to verify the performance of the piezoelectric element structure proposed in the present invention, and all the piezoelectric elements of the structure can have a similar fundamental frequency. 2 (a) and 2 (b) show a single piezoelectric device structure composed of a PMN-PT 100 and a PZT-5H 110, and FIGS. 2 (c) and 2 The structure is the same as that of the piezoelectric element according to the embodiment, but shows a structure in which the polarization is not reversed.

3 shows a simulation result of an FEM (finite element method) of the electrical impedance result according to the structure of the piezoelectric element. 3 (a) and 3 (b) show the results depending on the presence or absence of polarization reversal when multiple piezoelectric elements (such as PMN-PT and PZT-5H) Lithium niobate) is the result of the presence or absence of polarization reversal.

Referring to FIG. 3, it can be seen that only the fundamental frequency component is measured when the polarization inversion is not performed in all of the cases (a) to (c), and the amplitude of the fundamental frequency component decreases when the polarization inversion layer exists, Is generated. Therefore, it is possible to obtain a wide bandwidth signal including the fundamental frequency and the harmonic frequency component by controlling the thickness ratio of the multiple piezoelectric transducer having the polarization inversion according to the embodiment of the present invention.

4 shows FEM simulation results under various situations according to an embodiment of the present invention. 4 (a) and 4 (b) show the FFT (Fast Fourier Transform) of the result of the pulse echo test performed using the FEM simulation by bonding the sound-absorbing layer and the multiple matching layer on the basis of the structures (a) transform spectrum.

FIG. 4A shows the result of the device having the high-frequency broadband characteristic shown in FIG. 1A, FIG. 4B shows the result of the device having the multi-frequency harmonic characteristic shown in FIG. Results. 4A and 4B are views for explaining the effect of the structure according to an embodiment of the present invention. FIG. 4A is a cross-sectional view of the structure of FIGS. 2A, 2B, And Fig. 4 (b) can be compared with the structures (a), (b) and (d) of Fig.

Referring to FIG. 4A, in the case of the first element 100 and the second element 110 structure (for example, FIGS. 2A and 2B) composed of a single piezoelectric element, 6 dB bandwidth is similar to each other. For example, the first element 100 may be PMN-PT and the second element 110 may be PZT-5H, but not necessarily limited thereto.

It can be seen that the fundamental frequency and -6 dB bandwidth in the case of multiple piezoelectric elements without polarization inversion (e.g., Fig. 2 (c)) are similar to a single piezoelectric element. On the other hand, it can be seen that the fundamental frequency is increased about 1.5 times and the -6 dB bandwidth is increased compared with the single piezoelectric element, that is, the bandwidth is increased in the case of the structure in which the polarization inversion and the thickness ratio control of the multiple piezoelectric elements are controlled.

Referring to FIG. 4 (b), the fundamental frequency range of a PMN-PT, PZT-5H structure composed of a single piezoelectric element and a multiple piezoelectric element structure without polarization inversion (for example, And the harmonic frequency component does not occur when the amplitude of the spectrum is checked up to -40 dB. However, in a multiple piezoelectric device structure in which polarization reversal is performed, a fundamental frequency component may generate a harmonic frequency component having the same amplitude as a single piezoelectric device and a multiple piezoelectric device not having a polarization reversal but having an amplitude similar to a fundamental frequency component. As a result, a device having a multiple frequency harmonic characteristic by controlling the polarization reversal and the thickness ratio of the multiple piezoelectric device has a similar basic frequency component to the single piezoelectric device structure, but the harmonic frequency component is greatly improved, . Also, the filtering effect can be increased by using the valley-shaped interval between the fundamental frequency component and the harmonic frequency component.

FIG. 4C shows the results when the devices having the high frequency broadband and multi-frequency harmonic characteristics shown in FIGS. 4A and 4B are operated simultaneously. The harmonic frequency bandwidth is much higher than the fundamental frequency bandwidth, and the valley between the fundamental frequency component and the harmonic frequency component is deeper than that of a device having a general multi-frequency harmonic characteristic, thereby improving the performance of the harmonic image and increasing the filtering effect .

4D shows the result of performing the same simulation using one LiNbO3 piezoelectric element, unlike the case of the PMN-PT 100 and the PZT-5H 110, which are different piezoelectric elements described above. Referring to FIG. 4D, it can be seen that the results are substantially similar to those obtained by using different piezoelectric elements through the PMN-PT 100 and the PZT-5H 110. In the case of high frequency broadband characteristics, It can be seen that both the fundamental frequency component and the harmonic frequency component are generated simultaneously in the multi-frequency harmonic characteristic structure. Also, it can be seen that even in the case of the high-frequency wide-band and multi-frequency harmonic characteristic signal sum, the harmonic frequency component is the widest in the harmonic frequency component. As a result, the high frequency broadband and multi- It can be seen that the piezoelectric element can be manufactured using other types of piezoelectric elements and the same element.

FIG. 5 illustrates a process of fabricating an ultrasonic transducer capable of simultaneously having a high-frequency broadband and a multi-frequency harmonic characteristic according to an embodiment of the present invention. In other words, an efficient array ultrasonic transducer for diagnosing simultaneously high-frequency broadband and multi-frequency harmonic characteristics using multiple piezoelectric element polarization inversion can be manufactured through the same process as shown in FIG. According to an embodiment of the present invention, devices having respective characteristics are sequentially arranged and each mode can be operated independently or simultaneously.

5A, the polarities of the PMN-PT 100 and the PZT-5H 110 used as the multiple piezoelectric elements are aligned in the same direction in the direction of the ultrasonic energy, As shown in the figure, the surfaces of the PMN-PT 100 and the PZT-5H 110 can be cut to the same width by using a precision cutter. Each of the piezoelectric elements cut in the same width is bonded such that the polar directions 120 are opposed to each other as shown in FIGS. 5C and 5D, and the multiple piezoelectric elements bonded as shown in FIG. In order to distinguish the devices with the characteristics, a precision cutter can be used to generate the Kerf. The generated tooth width can be filled with filler such as epoxy or the like to be hardened. When the filler in the width of the chip is hardened, it is possible to perform lapping on at least one of the upper surface and the lower surface of the multiple piezoelectric elements so as to have a desired fundamental frequency component as shown in FIG. 5 (f). 5 (g), the arrangement type piezoelectric element 200 having a polarization inversion layer can be obtained (manufactured).

In order to manufacture an array type ultrasonic transducer using the array type piezoelectric transducer 200 having a polarization reversed layer manufactured according to an embodiment of the present invention, a signal line on the surface of the printed circuit board 180 for signal application to each element The arrayed piezoelectric element 200 having a polarization inversion layer is bonded to the arrayed piezoelectric element 200 having a polarization inversion layer and the ground layer 190 is bonded to the arrayed piezoelectric element 200 having a polarization inversion layer, Can be completed. The multiple matching layers such as the sound absorbing layer 150 and the first matching layer 160 and the second matching layer 170 are joined to form a diagnosis array type ultrasound having a high frequency broadband and multi frequency harmonic characteristic using the multiple piezoelectric element polarization inversion A converter 210 may be obtained.

6 is a block diagram of an ultrasound system capable of acquiring an ultrasound image using an ultrasound transducer according to an embodiment of the present invention. The ultrasound system according to an embodiment of the present invention may include an array type ultrasound transducer having high frequency broadband and multiple frequency harmonic characteristics through the multiple piezoelectric element inversion and thickness ratio control shown in FIG. In addition, the ultrasonic system according to an embodiment of the present invention can selectively drive an element having a high-frequency broadband characteristic and a multi-frequency harmonic characteristic according to a user's purpose by using the above-described ultrasonic transducer, So that an ultrasound image can be obtained.

The ultrasonic system according to an embodiment of the present invention includes a switch 240, a controller 250, a high frequency broadband device signal line 320, a multiple frequency harmonic device signal line 330, a sensor signal generator 260, And an ultrasonic image monitor 350. The ultrasonic imaging apparatus includes an ultrasonic imaging apparatus 270, a transmission amplification unit 280, a reception amplification unit 290, a reception focusing unit 300, a signal processing unit 310, An ultrasound transducer 210, a normalization unit 370, an operation unit 340, and a sum signal line 360 of two characteristics.

Referring to FIG. 6, the ultrasound system according to an exemplary embodiment of the present invention may include a switch 240 that allows a user to individually or simultaneously operate a high frequency broadband characteristic and a multiple frequency harmonic characteristic. In addition, the ultrasonic system according to an embodiment of the present invention is connected to a controller 250 that controls a driving element according to a selected mode by operating a switch 240 and controls the number of channels driven in the array-type ultrasonic transducer . The control unit 250 can drive the devices having the high frequency broadband characteristic and the multiple frequency harmonic characteristic or the devices having the two characteristics simultaneously through the high frequency broadband signal line 320 and the multiple frequency harmonic signal line 330. The signal output from the controller 250 is input to the sensor signal generator 260 to allow the user to generate a signal according to the selected mode by operating the switch 240. The signal is transmitted to the transmission focusing unit 270, So that the signal delay of each signal according to the focusing distance can be adjusted. The transmission amplifying unit 280 amplifies the magnitude of the signal output from the transmission focusing unit 270 and applies a signal to an element having the selected characteristic in the ultrasonic transducer 210 to apply ultrasonic waves to the object through the signal . The signal reflected from the object is again received through the ultrasonic converter 210. The signal received by the ultrasonic converter 210 may be received by the receiving amplifier 290 to amplify the signal.

The signals input to the reception amplifier 290 can receive all three types of signals according to a mode selected by the user, such as a high frequency broadband signal, a multi-frequency harmonic signal, a high frequency broadband characteristic, In the case of a signal combining high-frequency broadband and multi-frequency harmonic characteristics, each signal adjusts the amplitude of each signal through the normalizer 370, adds up the two signals in the calculator 340, 290). In the normalizer 370, when the difference in magnitude of the two signals is small, normalization of the signal can be selectively performed without normalization.

In the reception focusing unit 300, a signal delayed by each element is aligned on the basis of the signal received from the reception amplification unit 290, and in the signal processing unit 310, the ultrasound image is displayed by the ultrasound image monitor 350 A processing operation can be performed.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: first element 110: second element
120: polar direction 130:
140: Wrapping line 150: Sound absorbing layer
160: first matching layer 170: second matching layer
180: printed circuit board 190: ground layer
200: arrangement type piezoelectric element having a reverse layer
210: Array type ultrasonic transducer having high frequency broadband and multiple frequency harmonic characteristics
220: High frequency broadband characteristic element
230: Multi-frequency harmonic characteristic element
240: switch 250:
260: Sensor signal generator 270: Transmission focusing unit
280: transmission amplification unit 290: reception amplification unit
300: receive focusing unit 310: signal processing unit
320: High frequency broadband element signal line
330: Multiphase harmonic characteristic element signal line 340:
350: Ultrasonic image monitor
360: Sum signal line of two characteristics 370: Normalization unit

Claims (13)

In an array type ultrasonic transducer fabricated using a reverse layer technique,
By controlling the polarization reversal and the thickness ratio of the multiple piezoelectric elements, the high frequency broadband and multi-frequency harmonic characteristics can appear selectively or simultaneously,
A device exhibiting high frequency broadband characteristics and a device exhibiting multiple frequency harmonic characteristics are alternately arranged in parallel,
Wherein the polarization inversion thickness ratio of the device exhibiting the high frequency broadband characteristic is different from the polarization inversion thickness ratio of the device exhibiting the multiple frequency harmonic characteristic. The method according to claim 1,
Wherein the multiple piezoelectric elements included in the ultrasonic transducer are the same piezoelectric element or different types of piezoelectric elements. The method according to claim 1,
Wherein the ultrasonic transducer is joined in a multiple piezoelectric element structure for producing a device having the high frequency broadband and multiple frequency harmonic characteristics so that the polar directions of the respective elements are opposite to each other. The method according to claim 1,
Wherein the ultrasonic transducer is a multi-piezoelectric element structure for producing a device having the high-frequency broadband and multi-frequency harmonic characteristics, the thickness ratios of the respective devices being different. delete delete The method according to claim 1,
Wherein the ultrasound transducer comprises a single element transducer or an array type transducer. The method according to claim 1,
Wherein the fundamental frequency and bandwidth can be adjusted according to the material, thickness, or shape of the sound-absorbing layer and the multiple matching layer included in the ultrasonic transducer. The method according to claim 1,
A signal can be transmitted and received in one of a high-frequency wide-band mode, a multi-frequency harmonic mode, and a combining mode based on an operation of a switch connectable with the ultrasonic transducer,
Wherein the combining mode is a mode in which high frequency broadband and multiple frequency harmonic characteristics are combined. 10. The method of claim 9,
At least one element exhibiting high frequency broadband characteristics and at least one element exhibiting multi-frequency harmonic characteristics are simultaneously driven, and the signals received are summed in a calculation unit connectable with the ultrasonic transducer, And the ultrasonic transducer is selectively normalized by a normalization unit connectable to the ultrasonic transducer. A method for fabricating an arrayed ultrasonic transducer using a reverse layer technique,
Aligning the polarities of the first and second elements available as multiple piezoelectric elements so that they are equally spaced in the direction of ultrasonic energy propagation;
Cutting the surface of the first element and the surface of the second element into at least one columnar shape;
Joining the first element and the second element whose surfaces are cut so that their polar directions are opposite to each other;
Cutting a surface of the bonded element to produce a width (Kerf);
Filling the generated tooth width with a filler; And
And lapping the upper and lower surfaces of the bonded element so as to have a predetermined fundamental frequency component. 12. The method of claim 11,
Wherein the at least one column shape has the same width and the same height value,
And are spaced equidistantly from the surface. 12. The method of claim 11,
Bonding the bonded device to a signal line on a surface of a printed circuit board for applying a signal to the first device and the second device;
Bonding a ground layer to the top of the bonded device; And
Bonding a sound-absorbing layer to a lower portion of the bonded element, and bonding at least one matching layer to the upper portion of the bonded element.

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