JP2014023131A - Ultrasonic probe, and method of manufacturing the same - Google Patents

Abstract

In an ultrasonic probe including a 2D array transducer, effective backing is performed on the back side of each vibration element.
A back side member is provided on the back side of the array transducer. The back side member 30 is composed of a plurality of back side elements 32. Each back-side element 32 has a hollow lead 36 having a cylindrical shape. A transmission signal and a reception signal are transmitted through the hollow lead 36. The hollow lead 36 is filled with a backing material 38. A backing material 40 is also provided outside the hollow lead 36.
[Selection] Figure 1

Description

  The present invention relates to an ultrasonic probe and a method for manufacturing the same, and more particularly to a structure on the back side of an ultrasonic transducer.

  An ultrasonic diagnostic apparatus used in the medical field includes an ultrasonic diagnostic apparatus main body and an ultrasonic probe (probe). The ultrasound probe has a transducer assembly that includes an array transducer. Generally, in the transducer assembly, one or a plurality of matching layers and an acoustic lens (or a protective layer) are provided on the front side of the array transducer. A backing is provided on the back side of the array transducer. The backing absorbs and scatters ultrasonic waves radiated from the array transducer to the back side, and is provided so that an image is not deteriorated by multiple reflection of ultrasonic waves.

  Recently, an ultrasonic diagnostic apparatus having a three-dimensional measurement function is becoming popular. Such an ultrasonic diagnostic apparatus includes a 2D array transducer as an array transducer. The 2D array transducer is composed of a plurality of vibration elements arranged two-dimensionally. In the 2D array transducer, a plurality of signal lines are connected to the back surface of the 2D array transducer in order to supply a signal to each transducer element. For this reason, a multilayer substrate and an electronic device are provided on the back side of the 2D array transducer. Since they basically do not have a backing action, the ultrasonic waves emitted to the back side cannot be sufficiently absorbed and the ultrasonic image is deteriorated.

JP 2004-33829 A JP 2004-56504 A

  In the ultrasonic diagnostic apparatus disclosed in Patent Document 1, the backing provided on the back side of the 2D array transducer has a plurality of leads. Each lead is a linear member, that is, a thin wire. With such a configuration, it can be pointed out that there is a possibility that signal transmission and electrical connection cannot be reliably performed. In the ultrasonic diagnostic apparatus disclosed in Patent Literature 2, a thick lead is used as each lead, but in that case, the ultrasonic absorption action cannot be sufficiently generated on the back side of the 2D array transducer. Can point out the possibility.

  An object of the present invention is to realize a back structure capable of reliably performing electrical connection and signal transmission and obtaining an effective backing action. Moreover, it is to easily manufacture such a back structure.

  An ultrasonic probe according to the present invention includes an array transducer including a plurality of vibration elements, and a back surface member including a plurality of back elements provided on the back side of the array transducer and corresponding to the plurality of vibration elements. Each of the back-side elements includes a hollow lead that transmits a signal to a vibration element positioned above, and an interior made of a material that fills the internal space of the hollow lead and exhibits a backing function. Backing material.

  According to the above configuration, since the inside of the hollow lead is filled with the backing material, the ultrasonic wave emitted from the back side of each vibration element can be effectively attenuated and absorbed to improve the quality of the ultrasonic image. Since the hollow lead has a certain cross-sectional area, it can reduce the electrical resistance in comparison with the thin wire lead, and it is also equivalent to a thick lead, facilitating the positioning of the member, and at the same time the upper and lower sides The electrical connection can be reliably performed. In each rear element, it is desirable to provide an outer backing material outside the hollow lead. However, if a certain backing effect can be obtained by the inner backing material, a material that does not necessarily have a backing action is provided outside the hollow lead. You may do it. For example, the back member may be made of a base material ceramic, a resin, or the like, and the outside of the hollow lead may be made of such a material. The ultrasonic probe is preferably inserted into a body cavity, and particularly preferably inserted into the esophagus.

  Preferably, the hollow lead is composed of a conductive layer formed on the inner surface of the hollow hole. The hollow hole may be a through hole or a through hole, but may be a non-through hole. After forming the holes, it is possible to easily form a conductive layer having a certain thickness on the inner surface by plating or the like. An upper surface electrode may be formed on the upper surface of the back member when the hollow lead is formed, or such an upper surface electrode may be formed in advance or afterwards. Similarly, an electrode pattern may be formed on the lower surface of the back member in advance or afterwards. Preferably, the hollow lead has a cylindrical shape.

  Preferably, an electronic circuit device for channel reduction is provided on the back side of the back side member. In this configuration, the back member functions as a relay substrate between the array transducer and the device. In other words, in that case, a relay board with a backing action in element units is configured.

  Preferably, the back side member is a multilayer substrate having a plurality of internal electrode layers, and the plurality of hollow leads of the plurality of back side elements are plural types for connection to a plurality of wiring layers of the multilayer substrate. Have a length of The multilayer substrate may be a hard substrate or a flexible substrate. It is desirable that electrical connection to the plurality of vibration elements is performed on the upper surface side of the multilayer substrate, and electrical connection to the electronic circuit device is performed on the lower surface side of the multilayer substrate.

  The method according to the present invention includes a step of forming a plurality of hollow holes in a two-dimensional arrangement with respect to a back side member, and forming an electrode layer on the inner surface of the plurality of hollow holes, thereby forming a plurality of hollow leads. A step of filling the inner space of the plurality of hollow leads with a backing material, and a step of connecting the back member and the array transducer after the filling of the backing material.

  ADVANTAGE OF THE INVENTION According to this invention, an electrical connection and signal transmission can be performed reliably and the back surface structure which can obtain an effective backing action is realizable. Such a back structure can be easily manufactured.

1 is a cross-sectional view showing a first embodiment of an ultrasonic probe according to the present invention. It is a figure which shows the horizontal cross section of the back side member shown in FIG. It is a figure which shows the 2nd example of a back side element. It is a figure which shows the 3rd example of a back side element. It is a figure for demonstrating the manufacturing method of the ultrasonic probe which concerns on this invention. It is a figure which shows the vibrator | oscillator assembly produced by the process shown in FIG. It is sectional drawing which shows 2nd Embodiment of the ultrasonic probe which concerns on this invention.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

  FIG. 1 shows a cross-sectional view of the main configuration of an ultrasonic probe according to the present invention. FIG. 1 shows a first embodiment of an ultrasonic probe.

  The ultrasonic probe is connected to the ultrasonic diagnostic apparatus main body via a cable (not shown). The ultrasonic probe in this embodiment is a body cavity insertion type ultrasonic probe, particularly a transesophageal probe. The transesophageal probe has a probe head inserted into a living body, and the transducer assembly 10 is incorporated in the probe head.

  The vibrator assembly 10 will be described in detail. The array vibrator 12 includes a plurality of vibration elements 14 arranged two-dimensionally, that is, it is a so-called 2D array vibrator. A ground electrode layer 16 is provided on the upper surface side of the array vibrator 12, that is, on the upper side in the drawing. The ground electrode layer 16 is a sheet-like member made of thin copper or the like provided over a plurality of vibration elements. A ground electrode may be provided for each vibration element 14. Incidentally, although an electrode layer is formed on the upper surface side of each vibration element 14, it is not illustrated. A first matching layer 18 and a second matching layer 22 are formed on the upper surface side of the ground electrode layer 16. The first matching layer 18 is constituted by a plurality of matching elements 20 arranged two-dimensionally. Similarly, the second matching layer 22 is constituted by a plurality of matching elements 24. A protective layer 26 is provided on the upper surface side of the second matching layer 22. Ultrasonic waves are transmitted through the upper surface of the protective layer 26, and reflected waves from the living body are received.

  A back side member 30 is provided on the back side of the array transducer 12, that is, on the lower side in the figure. In the present embodiment, the back side member 30 forms a relay board. An electronic circuit device 42 is provided below the back side member 30. It is configured by an LSI in this embodiment.

  The back side member 30 includes a plurality of back side elements 32 having an arrangement similar to the arrangement of the plurality of vibration elements 14. That is, one back element 32 is provided corresponding to one vibration element 14. Each back element 32 includes a hollow lead 36 having a cylindrical shape. The hollow lead 36 is provided so as to penetrate the back side member 30 vertically. The upper end of the hollow lead 36 is connected to an electrode 28 provided on the lower surface side of the vibration element 14. Such an electrode 28 may be formed on the back side member 30. The lower side of the hollow lead 36 is connected to an electrode 46 formed on the upper surface of the electronic circuit device 42. Such an electrode 46 may be formed on the back side member 30. Reference numeral 44 denotes an electrode array.

  In each rear element 32, the inside of the hollow lead 36 is filled with a backing material 38. That is, it is an internal backing material. The backing material 38 has a cylindrical shape. In each back element 32, a backing material 40 is also provided outside the hollow lead 36. That is, in the configuration shown in FIG. 1, the back side element 32 is provided on the back side of each vibration element 14, and the backing function is exhibited in the back side element 32 except for the hollow lead 36. Thereby, unnecessary ultrasonic waves emitted from the back side of each vibration element 14 are effectively attenuated and absorbed. In the present embodiment, since the hollow lead 36 has a relatively large diameter and the inside thereof is filled with the backing material 38, the backing action can be positively exhibited in the central portion of the vibration element 14. The hollow lead 36 has a certain thickness on the horizontal cross section, and corresponds to a considerably thick lead as a whole, so that the electrical resistance can be reduced and the positioning of the members on the upper surface side and the lower surface side of the hollow lead 36 can be performed. It can be easily performed, and electrical connection can be reliably performed. In the embodiment shown in FIG. 1, the backing material 40 is also provided outside the hollow lead 36, but the portion may be ceramic, resin, or the like.

  The electronic circuit device 42 is equipped with an electronic circuit for channel reduction in this embodiment. That is, it has a circuit that performs grouping, first stratified addition processing, and the like on a plurality of vibration elements. The electronic circuit device 42 also includes a transmission circuit. By providing an electronic circuit having a channel reduction function in the probe head in this way, the number of signals output from the electronic circuit can be greatly reduced. As a result, the probe cable and thus the portion inserted into the body cavity can be made thinner. Reference numeral 50 has a flexible printed circuit board. Reference numeral 48 denotes a connector. Incidentally, the back side member 30 may be configured as a flexible member. In addition, it is desirable to construct a heat conduction system so that the rear side member 30 can effectively dissipate heat.

  FIG. 2 shows a horizontal section indicated by II in FIG. Each back element 32 has the hollow lead 36 as described above, and since it has a cylindrical shape, its cross section is ring-shaped. In the present embodiment, the inner diameter is set to be approximately half the length of one side of the back-side element 32, that is, a relatively large amount of backing material 38 is filled in the hollow lead 36. Thereby, effective backing can be performed inside the hollow lead 36. Further, since the backing material is also provided outside the hollow lead 36, effective backing can be performed there. There is a separation groove between the adjacent back side elements 32, which is created by a dicing saw or the like. It is filled with a member for preventing acoustic crosstalk. In FIG. 1, such a separation groove 34 is shown, and a lower end 34 a thereof enters the back side member 30.

  FIG. 3 shows a second example of the back side element. The back-side element 52 has a hollow lead 54 having a cylindrical shape, and the inside thereof is filled with a backing material 56. However, the ceramic 58 is provided on the outer side of the hollow lead 54, that is, the backing action is not exerted particularly on the outer side of the hollow lead 54. Such a ceramic 58 constitutes the base material of the back side member.

  FIG. 4 shows a third example of the back side element. In this example, a prismatic hollow lead 62 is provided in the back element 60, and as shown in the drawing, the cross section is rectangular, that is, a quadrangle. The inside of the hollow lead 62 is filled with a backing material 64. A backing material 66 is also filled outside the hollow lead 62.

  The example shown in FIG. 3 is easy to manufacture. According to the example shown in FIG. 4, the amount of the backing material in the hollow lead 62 can be increased. The backing action may be increased by increasing the diameter or length of one side of the hollow lead.

  5 and 6 show a method for manufacturing an ultrasonic probe. In FIG. 5, (A) shows the back side member 68 before processing. In the example of illustration, it is comprised as one homogeneous member. In the step shown in (B), a plurality of through holes 70 are formed with a two-dimensional array. In the step shown in (C), a plating process is performed, whereby a conductive layer 72 is formed on the inner surface of each through hole 70. This conductive layer 72 corresponds to a hollow lead. Electrode layers are also formed on the upper and lower surfaces of the back side member. In the step shown in (D), the backing material 78 is filled in each hollow lead 72. Incidentally, reference numerals 80 and 82 denote portions where separation grooves are formed.

  A structure as shown in FIG. 6 can be obtained by bonding a diaphragm made of a piezoelectric material to the back-side member configured as described above and performing element cutting. Reference numeral 84 denotes a back side member, and reference numeral 86 denotes an array transducer. Reference numeral 92 represents an element isolation groove. The formation of the element isolation grooves 92 constitutes a plurality of vibration elements 90, and a plurality of back side elements 88. Reference numeral 96 denotes a hollow lead. The hollow lead 96 is filled with a backing material 94.

  After the above steps, a vibrator assembly is configured by performing necessary assembly work and the vibrator assembly is disposed in the probe head. After the arrangement, processing such as cable connection and resin molding is performed as necessary.

  FIG. 7 shows a cross-sectional view of the main configuration of the ultrasonic probe according to the second embodiment. In the probe head 100, reference numeral 102 denotes a head case, and a vibrator assembly 130 is disposed therein. The array transducer 106 is composed of a plurality of two-dimensionally arrayed vibration elements. A ground electrode layer 108 is provided on the upper surface side, and a first matching layer 110 and a second matching layer 112 are provided on the upper surface side. Is provided. A protective layer 114 is provided above the second matching layer 112.

  A back side member 104 is provided below the array transducer 116. The back side member 104 is a multilayer substrate in this embodiment. That is, a plurality of circuit patterns are provided in the inside in the vertical direction. Each circuit pattern is formed in a horizontal plane, and electrical connection is made at predetermined positions between the circuit patterns.

  The back-side member 104 includes a plurality of back-side elements 106 corresponding to the individual vibration elements, and each back-side element 106 has a hollow lead 108. There are a plurality of hollow leads 108 as a whole of the plurality of back-side elements 106, and they have a plurality of types of lengths. In other words, each hollow lead has a predetermined length in order to make a connection to a connection point on the wiring pattern corresponding to each vibration element. The length of the hollow lead is desirably a length that can provide a sufficient backing effect. Of course, the points to be connected may be appropriately determined for each of them while maintaining the same length. Each hollow lead 108 is filled with a backing material 110.

  In the rear surface side member 104, a plurality of hollow leads are electrically connected to a plurality of vibration elements on the upper surface side. On the lower surface side of the plurality of hollow leads 108, they are electrically connected to corresponding wiring patterns. An electronic circuit device 116 is provided below the back side member 104. This electronic circuit device 116 is a channel reduction circuit. An electrode pad array 118 is provided on the upper surface side. A plurality of electrode pads are connected to a plurality of electrodes 120 provided in the back side member 104. Each electrode 120 constitutes a vertical electrode that has entered from the electronic circuit device 116 side inward. The length is the length that reaches the connection target circuit pattern.

  The plurality of vibration elements are connected to the electronic circuit device 116 via the back side member 104, and the electronic circuit device 116 is connected to the flexible circuit board 124 via the back side member and via the connector 122. Yes. Of course, such a configuration is an example. The back side member 124 constitutes a multi-layer substrate, in which electrical wiring can be performed with a three-dimensional circuit pattern.

  In any case, a backing material is provided on the back side of each vibration element, and the ultrasonic wave emitted from the back side of each vibration element can be attenuated and absorbed by the backing material. Thereby, the image quality of an ultrasonic image can be improved. Further, since a hollow lead is used, an advantage that electrical connection can be surely obtained can be obtained.

  DESCRIPTION OF SYMBOLS 10 vibrator | oscillator assembly, 12 array vibrator | oscillator, 16 ground electrode layer, 18 1st matching layer, 22 2nd matching layer, 26 protective layer, 30 back side member, 32 back side element, 36 hollow lead, 38 backing material, 42 Electronic circuit device.

Claims (6)

An array vibrator comprising a plurality of vibration elements;
A back side member comprising a plurality of back side elements corresponding to a plurality of vibration elements, provided on the back side of the array transducer;
Including
Each of the back side elements is
A hollow lead that transmits a signal to a vibrating element located above;
An internal backing material composed of a material that fills the internal space of the hollow lead and exhibits a backing action;
Ultrasonic probe characterized by including. The ultrasonic probe according to claim 1,
The hollow lead is composed of a conductive layer formed on the inner surface of the hollow hole,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 2,
The hollow lead has a cylindrical shape;
An ultrasonic probe characterized by that. The ultrasonic probe according to any one of claims 1 to 3,
An electronic circuit device for channel reduction was provided on the back side of the back side member,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1,
The back side member is a multilayer substrate having a plurality of internal electrode layers,
The plurality of hollow leads of the plurality of back-side elements have a plurality of types of lengths for connection to a plurality of wiring layers of the multilayer substrate.
An ultrasonic probe characterized by that. Forming a plurality of hollow holes with a two-dimensional arrangement with respect to the back side member;
Forming an electrode layer on the inner surfaces of the plurality of hollow holes, thereby forming a plurality of hollow leads; and
Filling an internal space of the plurality of hollow leads with a backing material;
Connecting the back side member and the array transducer after filling the backing material;
A method for manufacturing an ultrasonic probe, comprising:

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