JP2000300559A - Ultrasonic probe and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic probe and its manufacturing method to prevent cross talks between piezoelectric elements, and to uniform sound fields of ultrasonic beams. SOLUTION: This ultrasonic probe comprises first electrodes 5 provided on a rear side load member 4, a plurality of columnar piezoelectric elements (piezoelectric bodies) 1 arranged on the electrodes 5 so as to form a matrix, second electrodes 6 provided on these piezoelectric elements 1, a plurality of acoustic matching layers 2 arranged on the second electrodes 6 so as to form a matrix, and acoustic lenses 3 arranged on these acoustic matching layers 2 so as to form a matrix. Incidentally, an epoxy based resin 7 is filled around respective piezoelectric elements 1. The first electrodes 5 and the second electrodes 6 are formed of conductive metal films, e.g. gold respectively, and they are divided into matrixes to electrically connect to respective piezoelectric elements 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic probe used for an ultrasonic diagnostic apparatus for drawing and measuring a tomographic image of a living body mainly for medical diagnosis and a method for manufacturing the same. The present invention relates to an array-type ultrasonic probe in which a plurality of ultrasonic probes are arranged in a matrix and a method of manufacturing the same.

[0002]

2. Description of the Related Art An ultrasonic diagnostic apparatus obtains internal information of a living body by transmitting an ultrasonic pulse from an ultrasonic probe into a living body and analyzing a reflected signal (echo) from the living body. It is configured to be able to.

[0003] Ultrasonic probes applied to such an ultrasonic diagnostic apparatus are classified into several types according to a method of scanning and converging an ultrasonic beam in the path of the ultrasonic pulse.

For example, as shown in FIG. 9, an ultrasonic probe disclosed in Japanese Patent Application Laid-Open No. Hei 7-23500 has a plurality of piezoelectric elements 54 arranged in a matrix and a plurality of piezoelectric elements 54 arranged in a matrix. First and second electrodes 5 deposited on both sides
5, 53 and an acoustic matching layer 51 integrally formed on the second electrode 53, and the first electrode 55 is electrically connected to an external connection terminal 58 via a wiring pattern 57. Have been. Such an ultrasonic probe is called an array type or an electronic scanning type ultrasonic probe, and each piezoelectric element 5
4 and the first and second electrodes 55 and 53 constitute one unit ultrasonic probe (element), and tens to hundreds of these elements are arranged in a matrix.
Then, by selectively applying a pulse voltage having a predetermined delay time to a plurality of elements arranged in a matrix, the ultrasonic beam can be scanned.

[0005]

However, in the ultrasonic probe described above, since the piezoelectric element 54 is divided into a plurality of elements in a matrix, the acoustic matching layer 51 is integrated, It is difficult to accurately focus the ultrasonic beam in a predetermined direction due to the crosstalk between the piezoelectric elements, and as a result, the azimuth resolution is reduced.

In order to solve the problem of crosstalk,
For example, a method in which a piezoelectric element and an acoustic matching layer are adhered to each other to form a plate shape, and this is cut by a dicing device is conceivable, but since there is a lower limit on the cutting margin, it has to be cut straight. In addition, not only is the size of the ultrasonic probe reduced and the degree of freedom in design is limited, but also the acoustic matching layer may peel off from the piezoelectric element during cutting.

In order to improve the convergence of the ultrasonic beam, it is conceivable to add an acoustic lens layer 59 having a predetermined curvature on the acoustic matching layer 51 as shown in FIG. 10, for example. Since the thickness of the acoustic lens layer 59 through which the ultrasonic waves S generated from the piezoelectric element 54 pass, the attenuation rate of the ultrasonic waves S differs, and as a result, the sound field of the focused ultrasonic beam does not become uniform. there is a possibility.

The present invention has been made to solve such a problem, and an object of the present invention is to prevent crosstalk between piezoelectric elements and to make the sound field of an ultrasonic beam uniform. And a method of manufacturing the same.

[0009]

In order to achieve the above object, the present invention provides an ultrasonic wave having a plurality of piezoelectric elements arranged in a matrix and electrodes formed on both sides of the piezoelectric elements. A probe, in which a plurality of acoustic matching layers arranged in a matrix and an acoustic lens formed in a matrix or a linear manner on these acoustic matching layers are provided on one electrode. . The present invention also relates to a method of manufacturing an ultrasonic probe, wherein a plurality of openings formed in a matrix or linear shape are used as acoustic lenses in each opening of a first silicon substrate. Casting a material to be formed, and laminating a second silicon substrate having a plurality of openings formed in a matrix on the first silicon substrate. And a step of removing the first and second silicon base materials from each other.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ultrasonic probe according to a first embodiment of the present invention and a method for manufacturing the same will be described with reference to FIGS.
This will be described with reference to FIG.

As shown in FIGS. 1A and 1B, an ultrasonic probe according to the present embodiment includes a first electrode 5 provided on 5, a plurality of columnar piezoelectric elements (piezoelectric bodies) 1 arranged in a matrix, a second electrode 6 provided on these piezoelectric elements 1,
A plurality of acoustic matching layers 2 arranged in a matrix on the electrodes 6 of the above, and acoustic lenses 3 arranged in a matrix on these acoustic matching layers 2. The periphery of each piezoelectric element 1 is filled with an epoxy resin 7.

The first electrode 5 and the second electrode 6 are respectively
For example, it is composed of a conductive thin film of gold or the like, is divided into a matrix, and is electrically connected to each piezoelectric element 1. Specifically, the first electrode 5 electrically connects each piezoelectric element 1 in the X-axis direction, and the second electrode 6
Are electrically connected in the Y-axis direction.

The piezoelectric element 1 and the acoustic matching layer 2 have a columnar shape and stand upright at regular intervals, and the acoustic lens 3 has a hemispherical shape. One element is constituted by the acoustic matching layer 2 and the acoustic lens 3, and an ultrasonic probe is constituted by arranging a plurality of these elements in a matrix. Each element is set to have a diameter D of 16 μm and a height h of 100 μm. In this case, the aspect ratio is 6.25, and the period interval (pitch) p of each element is p.
Is 22 μm.

Next, a method of driving the above-described ultrasonic probe will be described with reference to FIG. FIG. 2 shows a configuration of an ultrasonic diagnostic apparatus using the ultrasonic probe according to the present embodiment.

A pulse wave delay circuit 23 is connected to each of the first electrode 5 and the second electrode 6, and each element arranged in a matrix is composed of the first electrode 5 and the second electrode 5. 6 is selectively driven by a pulse wave input to a specific address. That is, in the two-dimensional Euclidean space (see FIG. 1B), if XY values are specified, specific coordinates (specific addresses) are determined, and a pulse wave is input to the determined coordinates (address). Pulse wave delay circuit 2
The pulse wave generated from No. 3 is a signal delayed by a predetermined time with respect to the pulse wave generated from the pulse wave generation circuit 25. The delay amount of the pulse wave determines the traveling direction of the ultrasonic wave 28 and the focal position F. In this case, the control of the delay amount of the pulse wave is performed by the control circuit 24, and the scanning position of the ultrasonic wave 28 is input to the display device 27. On the other hand, the reflected wave from the subject 29 is converted into an electric signal through each element, and the electric signal is amplified by the amplifier 26 and then input to the display device 27 as a luminance signal to be input to the display device 27.
Is displayed.

According to such a configuration, each element (piezoelectric element 1, acoustic matching layer 2, acoustic lens 3) is divided and arranged in a matrix on the back load member 4, so that a cross between the elements is provided. While preventing talk,
The sound field of the ultrasonic beam can be made uniform, and as a result, an ultrasonic probe with excellent resolution can be realized.

Next, a method of manufacturing an ultrasonic probe will be described.
This will be described with reference to FIGS.

In the manufacturing method of the present invention, an element (piezoelectric element 1, piezoelectric element 1) is formed using a silicon mold formed of silicon.
The acoustic matching layer 2 and the acoustic lens 3) are formed. By using the silicon mold in this manner, the elements (piezoelectric element 1, acoustic matching layer 2, acoustic lens 3) can be divided and arranged in a matrix or linear shape. In addition, the matrix shape or the linear shape indicates a state where the position of each element is represented by one-dimensional and two-dimensional coordinates.

The manufacturing method used in the present embodiment is a lost mold method using a silicon mold formed by a reactive ion etching method. Nine steps to be described later, namely, (1) a step of forming a silicon mold (2) a step of casting a material to be used as the acoustic lens 3;
(3) a step of casting a material to be used as the acoustic matching layer 2, (4) a step of casting a PZT slurry, (5) a step of HIP treatment, (6) a step of depositing an electrode, (7) an acoustic lens 3, An ultrasonic probe is formed by a process of bonding the acoustic matching layer 2, the piezoelectric element 1, and the back load member 4, a process of removing a silicon mold, and a process of filling a resin and imparting piezoelectricity.

(1) Step of Forming Silicon Mold As shown in FIG. 3, three silicon bases 8, 9, 10 having different areas are stacked, and then these silicon bases 8, 9, 10 are stacked.
A photoresist 17 having a thickness of 6 μm is applied on the layers 9 and 10. The three silicon bases 8, 9, and 10 are a silicon mold 8 for a piezoelectric element, a silicon mold 9 for an acoustic matching layer, and a silicon mold 10 for an acoustic lens.

Then, portions for forming the piezoelectric element 1, the acoustic matching layer 2, and the acoustic lens 3 and the silicon bases 8, 9,
10, alignment markings 14, 1 formed at four places
Exposure processing and development processing are performed on the photoresist 17 so that the openings 5 and 16 become openings, and the photoresist 17 is patterned. At this time, the positional relationship between the alignment markings 14, 15, 16 is recorded in order to overlap the silicon molds 8, 9, 10 in a later step.

Subsequently, an etching process is performed by a reactive ion etching method so that each of the silicon bases 8, 9, and 1 is processed.
0, holes (openings) 11, 12, and 13 having a diameter of 16 μm and a total depth of 100 μm are formed in a matrix, and square alignment markings 14, 15, and 16 of 0.5 μm × 0.5 μm are formed. To form

Here, the reactive ion etching method will be described. The reactive ion etching method is a method of forming a hole having a high aspect ratio by repeatedly depositing and etching a block layer.
In this method, C ₄ F ₈ is used as a deposit gas and SF ₆ is used as an etching gas.

First, the deposit gas C ₄ F ₈ is turned into plasma to form a block layer made of fluoride on the side surface of the hole, the bottom of the hole,
It is deposited on the photoresist 17. Thereafter, an etching process is performed on each of the silicon substrate 8, 9 and 10 using an etching gas SF _6. In this etching process, the bottom of the hole is preferentially etched, and the side surface of the hole is hardly etched because fluoride functions as a block layer. By repeating this process, holes 11, 12, and 13 having a large aspect ratio are formed.

(2) Step of Casting Material Used as Acoustic Lens As shown in FIG. 4A, a silicone resin or the like is filled in the opening 13 of the acoustic lens silicon mold 10 created in the step (1). Fill. After the resin is cured, the surface of the acoustic lens silicon mold 10 having the opening 13 is polished to flatten the silicon mold 10 and the resin, thereby forming the acoustic lens 3.
To form

(3) Step of Casting a Material Used as an Acoustic Matching Layer As shown in FIG. 4B, a step (1) was performed on a silicon mold 10 for an acoustic lens on which an acoustic lens 3 was formed. After the acoustic matching layer silicon mold 9 is superimposed, the positioning marks 15 and 16 are positioned and fixed so that they have the same positional relationship as in patterning. That is, the openings 13 (see FIG. 3) of the silicon mold for acoustic lens 10 and the openings 12 (see FIG. 3) of the silicon mold 9 for acoustic matching layer are overlapped so as to coincide with each other.

Subsequently, an epoxy resin containing a filler such as Al ₂ O ₃ or CaCO ₃ is filled into the opening 12 of the silicon mold 9 for the acoustic matching layer. After the resin is cured, the surface of the opening 12 of the acoustic matching layer silicon mold 9 is polished to flatten the silicon mold 9 and the resin, thereby forming the acoustic matching layer 2.

Since the acoustic matching layer 2 and the acoustic lens 3 are made of resin, they are completely and integrally adhered to each other in this step. Here, a material composed of the acoustic matching layer 2 and the acoustic lens 3 formed on the silicon molds 9 and 10, which is the final stage of this process, is referred to as a sample 20.

(4) Step of Casting PZT Slurry As shown in FIG. 4C, while applying vibration to the piezoelectric element (PZT) slurry 17, the opening of the silicon mold 8 for the piezoelectric element formed in the step (1) is formed. For the part 11 (see FIG. 3),
The piezoelectric element slurry 17 is poured. At this time, one of the openings 11 of the silicon mold 8 for the piezoelectric element is closed with the silicon substrate 18. In addition, the piezoelectric element slurry 17 is
Piezoelectric element powder (Pb (Zr0.52Ti0.48)
O ₃ ), a mixture of PVA (polyvinyl alcohol) and water.

After that, air dry for about 12 hours or more.
After the piezoelectric element slurry 17 is turned into a green state, the piezoelectric element green body is heated and degreased to form the piezoelectric element 1 (see FIGS. 1 and 2). Here, degreasing means removing PVA, which is a binder of the piezoelectric element powder. In this state, the piezoelectric element 1 is not yet sufficiently filled in the opening 11 and is in a state of piezoelectric element powder.

(5) Step of HIPing Piezoelectric Element Powder In order to increase the density of the piezoelectric element powder 1 in the silicon mold 8 for piezoelectric element, the HIP (Ho
t Isostatic Pressing) processing.

As shown in FIG. 4D, a sample 21 composed of the silicon die 8 for the piezoelectric element, the piezoelectric element powder 1, and the silicon substrate 18 is wrapped in BN (boron nitride) powder and isotropically in water. Apply pressure to CIP (Cold Isostatic
Pressing) to obtain the piezoelectric element powder 1
Compress.

Next, sample 2 wrapped in boron nitride powder
1 was sealed in a Pyrex glass tube 19, and the degree of vacuum in the Pyrex glass tube 19 was reduced to about 10 ⁻³ Pa.
After evacuating to the state shown in FIG.
And sealed. In this case, the boron nitride powder is used to prevent a reaction between the sample 21 and the Pyrex glass tube 19.

Finally, HIP processing is performed. That is, the sample 21 sealed in the Pyrex glass tube 19 is
An isotropic pressure of 70 MPa is applied while being heated at about 1000 ° C. in an Ar gas atmosphere. Then, the temperature and the pressure are maintained for about 2 hours. After the completion of such HIP processing, the sample 21 is taken out of the Pyrex glass tube 19.

(6) Step of Depositing Electrode As shown in FIG. 5A, the sample 21 having undergone the step (5)
The piezoelectric element 1 is completely exposed by grinding and polishing both sides of the (piezoelectric element powder 1). Subsequently, a conductive material such as gold is deposited on the upper and lower surfaces of the sample 21 to form a first electrode 5 and a second electrode 6, respectively. Here, a material in which the first and second electrodes 5 and 6 are vapor-deposited on the piezoelectric element silicon mold 8 filled with the piezoelectric element 1, which is the final stage of this process, is referred to as a sample 22.

(7) Step of bonding acoustic lens 3, acoustic matching layer 2, piezoelectric element 1 and backing material 4 As shown in FIG. 5B, sample 20 (FIG.
(B)), the sample 22 (see FIG. 5 (a)) of the step (6) and the back load member 4 are superimposed and bonded to each other with an adhesive. When the sample 21 and the sample 22 are overlapped, the positioning marks 14 and 15 are positioned and fixed so that they have the same positional relationship as that at the time of patterning. That is, the piezoelectric element 1, the acoustic matching layer 2, and the acoustic lens 3 are positioned and fixed such that the respective elements vertically overlap on a straight line. The back load member 4 is fixed adjacent to the first electrode 5 of the sample 22.

(8) Step of Removing Silicon Mold As shown in FIG. 6A, the superimposed samples 21 and 22 are subjected to an etching treatment using XeF ₂ gas, thereby obtaining silicon molds 8, 9, and 9. Remove only 10

(9) Step of Filling Resin and Applying Piezoelectricity As shown in FIG. 6B, a gap between the plurality of piezoelectric elements 1 is filled with an epoxy resin 7. In the manufacturing method of the present embodiment, the epoxy resin 7 is filled while being evacuated, and then the epoxy resin 7 is cured. And the first
By applying a DC voltage between the first electrode 5 and the second electrode 6, the piezoelectric element 1 is polarized. As a result, piezoelectricity is imparted to the piezoelectric element 1, and an ultrasonic probe is completed.

According to the above-described manufacturing method, the acoustic lens 3, the acoustic matching layer 2, and the piezoelectric element 1 can be formed in a matrix. As a result, it is possible to realize an ultrasonic probe capable of preventing the crosstalk between the piezoelectric elements and making the sound field of the ultrasonic beam uniform. Furthermore, the use of the silicon molds 8, 9, and 10 eliminates the need to mechanically cut the acoustic lens 3 and the acoustic matching layer 2 as in the related art, so that the yield in manufacturing the ultrasonic probe is also reduced. improves.

The manufacturing method of the present invention is not limited to the above-described manufacturing method, but can be variously modified.

For example, the steps from the step (1) to the step (5) are the same, but before the step (6) (before depositing the electrodes), the silicon mold for the piezoelectric element 8 is formed using XeF ₂ gas. Is removed. Subsequently, after filling the epoxy resin 7 into the gaps between the plurality of piezoelectric elements 1, the piezoelectric element 1 and the epoxy resin 7 are ground and polished, and then the first and second electrodes 5 and 6 are deposited. I do. Then, the steps from step (7) to step (9) are performed in the same manner to complete the ultrasonic probe.

If the plurality of piezoelectric elements 1 have a polygonal cross section, for example, a rectangular parallelepiped, and the pitch between the piezoelectric elements 1 is larger than in the above-described embodiment, the piezoelectric elements 1 First and second electrodes 5 and 6, epoxy resin 7
May be manufactured without using the piezoelectric element silicon mold 8. For example, a method of cutting a piezoelectric element with a dicing device (Japanese Patent Laid-Open No. 7-23500)
After forming only the above-mentioned composite piezoelectric vibrator alone using, for example, a deep etch X-ray lithography method (see Sumitomo Electric 148 (1996) P129) or the like, a predetermined silicon mold is formed. It is also possible to manufacture an ultrasonic probe by bonding the acoustic matching layer 3 and the acoustic lens 2 formed using the above method.

Further, in the above-described embodiment, a reactive ion etching method is used as a method for etching a silicon base material.
A method combining a reactive ion etching method and a wet etching method may be used.

Next, an ultrasonic probe according to a second embodiment of the present invention and a method for manufacturing the same will be described with reference to FIG. In the description of the present embodiment, the same components as those of the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIGS. 7A to 7C, in this embodiment, the acoustic lens 3 is formed in a linear shape. Specifically, the acoustic lens 3 is divided in the X-axis direction, but is not divided in the Y-axis direction and has a predetermined curvature.

In this case, a reference pulse wave having no delay amount is input to all addresses of the second electrode 6, and the first electrode 5
, A pulse wave having a predetermined delay amount is input to each address. At this time, the Y-axis component of the ultrasonic wave generated from the ultrasonic probe is focused on a certain position by the refractive index between the acoustic lens 3 and the subject and the curvature of the acoustic lens 3. On the other hand, the X-axis component can change the focal position based on the delay amount.

Such a configuration is effective when the distance between the portion to be observed and the ultrasonic probe hardly changes and the scanning direction is constant, and the control thereof is facilitated. . The other configuration is the same as that of the above-described first embodiment, and a description thereof will be omitted.

As a method of manufacturing the ultrasonic probe according to the present embodiment, only the step (1) of the above-described first embodiment is slightly different, and the other steps (2) to (9) are the same. It is.

That is, in step (1), there are portions that do not match the holes (openings) 11, 12, and 13 (see FIG. 3) of the silicon mold 10 for the acoustic lens and the other silicon molds 8 and 9; The holes 11, 12, 13 and the alignment markings 14, 15, 15 are formed in three silicon types (silicon type 8 for piezoelectric element, silicon type 9 for acoustic matching layer, silicon type 10 for acoustic lens) by the reactive ion etching method.
After forming 16, the silicon mold for acoustic lens 10 is etched again to form a linear groove.

As described in the first embodiment, after forming only the composite piezoelectric vibrator alone without using the silicon mold, the acoustic matching layer 3 and the acoustic lens 2 are adhered to each other, It is also possible to manufacture an acoustic probe.

As described above, according to the ultrasonic probe and the method of manufacturing the same according to the present embodiment, as in the first embodiment,
Crosstalk between the piezoelectric elements can be prevented, and the sound field of the ultrasonic beam can be made uniform.

Next, an ultrasonic probe according to a third embodiment of the present invention and a method for manufacturing the same will be described with reference to FIG. In the description of the present embodiment, the same components as those of the above-described first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 8, in this embodiment, the acoustic matching layer 3 and the acoustic lens 2 are both divided into a matrix, but the pitch (period) between each acoustic matching layer 3 and each acoustic lens The pitch (period) between the two piezoelectric elements 1 is designed to be larger than the pitch (period) between the piezoelectric elements 1. That is, the plurality of piezoelectric elements 1 share one element for the acoustic matching layer 3 and the acoustic lens 2, and an ultrasonic probe is configured by a set of these elements.

According to the ultrasonic probe having such a structure,
Wiring patterns can be simplified, and as a result, manufacturing costs can be reduced. Note that other configurations are the same as those of the above-described first embodiment.
The description is omitted.

Further, the manufacturing method of the present embodiment is similar to that of the above-described second embodiment, in that each silicon mold 8, 9, 1
Since there are portions that do not coincide with the zero holes (openings) 11, 12, and 13, the silicon molds 9 and 10 for the acoustic matching layer and the acoustic lens must be re-etched. Further, as described in the first embodiment, it is also possible to form only the composite piezoelectric vibrator alone without using the silicon mold.

As described above, according to the ultrasonic probe and the method of manufacturing the same according to the present embodiment, the crosstalk between the piezoelectric elements can be prevented, and the ultrasonic probe can be used, as in the first and second embodiments. The sound field of the sound beam can be made uniform.

[0057]

According to the present invention, it is possible to provide an ultrasonic probe capable of preventing crosstalk between piezoelectric elements and making the sound field of an ultrasonic beam uniform, and a method of manufacturing the same. Can be.

[Brief description of the drawings]

FIG. 1A is an exploded perspective view showing a configuration of an ultrasonic probe according to a first embodiment of the present invention, and FIG. 1B is an exploded perspective view showing an ultrasonic probe according to the first embodiment of the present invention. FIG. 2 is a perspective view showing a configuration of an acoustic probe.

FIG. 2 is a block diagram showing a configuration of an ultrasonic diagnostic apparatus using the ultrasonic probe according to the first embodiment of the present invention.

FIG. 3 is a view for explaining the method for manufacturing the ultrasonic probe according to the first embodiment of the present invention, and is a view showing a step of forming a silicon mold.

FIG. 4 is a view for explaining a method of manufacturing the ultrasonic probe according to the first embodiment of the present invention, wherein (a) shows a step of casting a material used as an acoustic lens. FIG. 2B is a view showing a step of casting a material used as an acoustic matching layer, FIG. 2C is a view showing a step of casting a PZT slurry, and FIG.
The figure which shows the process of HIP-processing a piezoelectric element powder.

5A and 5B are views for explaining the method for manufacturing the ultrasonic probe according to the first embodiment of the present invention, wherein FIG. 5A is a view showing a step of depositing an electrode, and FIG. FIG. 4 is a view showing a step of bonding an acoustic lens, an acoustic matching layer, a piezoelectric element, and a back load material.

6A and 6B are views for explaining the method of manufacturing the ultrasonic probe according to the first embodiment of the present invention, wherein FIG. 6A is a view showing a step of removing a silicon mold, and FIG. () Is a diagram showing a resin filling and piezoelectricity providing step.

FIG. 7A is a perspective view showing a configuration of an ultrasonic probe according to a second embodiment of the present invention, and FIG.
(C) is a cross-sectional view taken along line bb of FIG.
Sectional drawing which follows the c line.

FIG. 8 is a sectional view showing a configuration of an ultrasonic probe according to a third embodiment of the present invention.

FIG. 9 is a perspective view showing a configuration of a conventional ultrasonic probe.

FIG. 10 is a cross-sectional view showing a configuration of a conventional ultrasonic probe with improved convergence of an ultrasonic beam.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piezoelectric element (piezoelectric substance) 2 Acoustic matching layer 3 Acoustic lens 4 Back load material 5 First electrode 6 Second electrode 7 Epoxy resin

Continued on the front page (72) Inventor Tomoki Funakubo 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Industrial Co., Ltd. (72) Inventor Norihiko Sawada 2-43-2 Hatagaya, Shibuya-ku, Tokyo Ori (72) Inventor Masayoshi Esashi Inventor Masayoshi Esashi 1-11-9, Yagiyama-Minami, Taihaku-ku, Sendai, Miyagi Prefecture F-term (reference) 2G047 AC13 BA03 CA01 EA02 EA04 GB02 GB16 GB21 GB25 GB28 GB32 GH07 4C301 EE02 GB10 GB21 GB27 GB33 5D019 AA00 AA26 BB02 BB19 FF04 GG01 GG03

Claims (2)

[Claims] 1. An ultrasonic probe comprising a plurality of piezoelectric elements arranged in a matrix and electrodes formed on both surfaces of the piezoelectric elements, wherein one of the electrodes has a matrix. An ultrasonic probe comprising: a plurality of acoustic matching layers formed as described above; and an acoustic lens formed in a matrix or linear shape on the acoustic matching layers. 2. The method for manufacturing an ultrasonic probe according to claim 1, wherein each of the openings of the first silicon substrate having a plurality of openings formed in a matrix or a linear shape. Casting a material to be used as an acoustic lens, and laminating a second silicon substrate having a plurality of openings formed in a matrix on the first silicon substrate, and then forming an acoustic matching layer A manufacturing method comprising: a step of casting a material to be used in each opening of a second silicon base; and a step of removing the first and second silicon bases.