JP6594807B2 - Ultrasonic probe - Google Patents

Description

  The present invention relates to an ultrasonic probe, and more particularly to the structure of an ultrasonic probe provided with a two-dimensional array transducer.

  An ultrasonic probe is a transducer for ultrasonic diagnosis of a living body, and generally has a laminated body (a transducer assembly, a transducer unit) including an array transducer. The array vibrator is composed of a plurality of vibration elements. Each vibration element is made of, for example, a piezoelectric material or a composite material including the piezoelectric material. One or a plurality of matching layers are provided on the upper surface side (biological side) of the array transducer. A backing member for attenuating or absorbing unwanted ultrasonic waves radiated from the array transducer to the back side is provided on the lower surface side (non-biological side) of the array transducer. A resonance layer, a reflection layer, or the like may be provided between the array transducer and the backing member.

  As an array transducer, a two-dimensional array transducer is known in addition to a one-dimensional array transducer. The two-dimensional array transducer is usually used when ultrasonic waves are transmitted / received to / from a three-dimensional space in a living body. The backing member provided on the back side of the two-dimensional array transducer generally includes a two-dimensional lead array for connecting a plurality of signal lines to a plurality of vibration elements constituting the two-dimensional array transducer. The two-dimensional lead array is composed of a plurality of leads arranged two-dimensionally.

  For example, Patent Document 1 discloses an invention relating to the structure of a backing member having a two-dimensional lead array. Patent Document 2 describes an ultrasonic transducer having a vibrator in which a part of a backing member is formed in a convex shape, and Patent Document 3 is coupled to an integrated circuit via a flip chip bump. An ultrasonic transducer having an array of acoustic elements is described.

JP2015-228932A Japanese Patent No. 5820511 Special table 2008-509774 gazette

  The ultrasonic probe disclosed in Patent Document 1 improves the backing action of the backing member provided on the back side of the two-dimensional array transducer, and the electrical property of the two-dimensional lead array included in the backing member. It is an epoch-making thing that can improve the physical characteristics.

  The inventors of the present application have conducted research and development on a further improvement technique for the innovative ultrasonic probe disclosed in Patent Document 1.

  An object of the present invention is to provide an improved technique related to the structure of an ultrasonic probe provided with a two-dimensional array transducer.

  An ultrasonic probe suitable for the above object is provided with a two-dimensional array transducer composed of a plurality of two-dimensionally arranged transducer elements and a back side of the two-dimensional array transducer, and the plurality of transducers A backing member having a plurality of leads electrically connected to the element, a plurality of lead electrodes provided on the back surface of the backing member and electrically connected to the plurality of leads, and a surface on the backing member side The signal processing layer provided with a plurality of signal electrodes, the plurality of lead electrodes provided on the back surface of the backing member, and the plurality of signal electrodes provided on the surface of the signal processing layer are electrically connected. And a plurality of bumps.

  The ultrasonic probe having the above configuration includes a plurality of lead electrodes provided on the back surface of the backing member and a plurality of signal electrodes provided on the surface of the signal processing layer. The plurality of lead electrodes and the plurality of signal electrodes are provided. Are electrically connected. For example, each lead electrode and each signal electrode that are in a corresponding relationship are electrically connected. The back surface of the backing member provided with a plurality of lead electrodes and the surface of the signal processing layer provided with the plurality of signal electrodes are preferably parallel to each other. For example, if the back surface of the backing member and the surface of the signal processing layer are completely parallel, it is relatively easy to directly connect the plurality of lead electrodes and the plurality of signal electrodes. However, it is difficult to make the back surface of the backing member and the surface of the signal processing layer completely parallel due to the influence of, for example, differences in materials and manufacturing methods. When the other surface is warped with respect to one surface, for example, when the back surface of the backing member is flat but the surface of the signal processing layer is warped, these two surfaces (back surface of the backing member and signal Since the distance between each lead electrode and each signal electrode provided on the surface of the treatment layer is not uniform in the plane, it is difficult to directly connect the plurality of lead electrodes and the plurality of signal electrodes. According to the ultrasonic probe having the above configuration, since the plurality of lead electrodes and the plurality of signal electrodes are electrically connected via the plurality of bumps, for example, the distance between each lead electrode and each signal electrode is a surface. Even in the case of non-uniformity, for example, by making at least some of the plurality of bumps have different heights, the non-uniformity is eliminated or reduced by the plurality of bumps, and the plurality of lead electrodes and the plurality of signal electrodes The reliability of the electrical connection between can be increased. Therefore, it is desirable to change the height of each bump according to the distance between each lead electrode and each signal electrode. For example, each bump desirably has a material and a shape suitable for changing the height by bonding when the backing member and the signal processing layer are bonded. For example, the material of each bump is preferably a metal such as gold (Au), and the shape of each bump is preferably a convex shape. For example, if a plurality of bumps are provided on a plurality of signal electrodes, and each bump is a tapered convex shape on the backing member side, some bumps are crushed by corresponding lead electrodes, or corresponding lead electrodes Each signal electrode and each lead electrode can be electrically connected while changing the height, which is the distance from each signal electrode to each lead electrode.

  In a preferred embodiment, the bumps are disposed between the lead electrodes and the signal electrodes to electrically connect the lead electrodes and the signal electrodes.

  In a preferred embodiment, each of the bumps has a tapered convex shape on the side of each lead electrode.

  In a preferred embodiment, each bump is placed on each signal electrode and electrically connected to each signal electrode.

  In a preferred embodiment, at least one of the plurality of bumps pierces each lead electrode and is electrically connected to each lead electrode.

  In a preferred embodiment, at least one of the plurality of bumps is crushed while being in contact with each lead electrode, and is electrically connected to each lead electrode.

  In a preferred embodiment, the ultrasonic probe further includes a conductive paste that is provided on the lead electrode side of each bump and electrically connects the bump and the lead electrode. And

  In a preferred embodiment, the ultrasonic probe is filled between the back surface of the backing member and the surface of the signal processing layer, and the curing shrinkage agent structurally connects the backing member and the signal processing layer. It further has these.

  In a preferred embodiment, the curing shrinkage material is a resin to which at least one of an acoustic attenuation filler and an acoustic scattering filler is added.

  In addition, a preferable method for manufacturing an ultrasound probe that meets the above-described purpose includes a plurality of leads that are electrically connected to a plurality of vibration elements that form a two-dimensional array transducer, and the plurality of leads are electrically connected. Manufacturing a backing member having a plurality of lead electrodes connected to each other on the back surface, manufacturing a signal processing layer having a plurality of signal electrodes on the surface, and a plurality of signal electrodes on the surface of the plurality of signal electrodes A step of forming a bump; and a step of bonding a back side of the backing member and a surface side of the signal processing layer. In the bonding step, the plurality of the plurality of the plurality of bumps provided on the back side of the backing member The lead electrode and the plurality of signal electrodes provided on the surface of the signal processing layer are electrically connected through the plurality of bumps.

  According to the present invention, an improved technique relating to the structure of an ultrasonic probe including a two-dimensional array transducer is provided. For example, according to a preferred aspect of the present invention in which a plurality of lead electrodes and a plurality of signal electrodes are electrically connected via a plurality of bumps, the distance between each lead electrode and each signal electrode is a surface. Even in the case of non-uniformity, the non-uniformity is eliminated or reduced by the plurality of bumps, and the reliability of electrical connection between the plurality of lead electrodes and the plurality of signal electrodes can be improved.

It is a figure which shows the transducer | vibrator assembly of the ultrasonic probe which is a specific example of this invention. It is a figure for demonstrating the structure of the connection part of a backing member and a relay board | substrate. It is a figure which shows the specific example of the connection state of each bump. It is a figure which shows the curvature of a relay board | substrate. It is a flowchart which shows the specific example of the manufacturing method which concerns on this invention.

  Preferred embodiments of the present invention will be described with reference to the drawings. However, the ultrasonic probe (the present ultrasonic probe) to be described below with reference to the drawings is one specific example suitable for implementing the present invention, and the present invention is a specific example thereof. It is not limited to only.

  This ultrasonic probe is a body surface contact type and can be used for diagnosis of, for example, the heart. Of course, the structure of the ultrasonic probe described below may be applied to a probe inserted into a body cavity. The ultrasonic probe includes a transducer assembly (vibrator unit), and exchanges signals with the ultrasonic diagnostic apparatus main body by, for example, wired connection via a cable or wireless connection without a cable. .

  FIG. 1 is a diagram showing a specific example of a transducer assembly 10 included in the ultrasonic probe. FIG. 1 shows a ZX cross section of the transducer assembly 10 in the XYZ orthogonal coordinate system. There is a Y axis as an axis orthogonal to the Z axis and the X axis. The vibrator assembly 10 has a two-dimensional array vibrator 12. The two-dimensional array transducer 12 is configured by a plurality of vibrating elements 14 aligned in the X direction and the Y direction, for example, in an XYZ orthogonal coordinate system.

  Each vibration element 14 converts a transmission signal into an ultrasonic wave, and converts an ultrasonic reflected wave obtained from the living body into a reception signal. In the specific example of FIG. 1, each vibration element 14 includes a piezoelectric body 14a and a hard backing (HB) 14b. The piezoelectric body 14a is made of a piezoelectric material or the like. The hard backing 14b is made of tungsten or the like and functions as a fixed end of vibration generated by the piezoelectric body 14a. In addition, each vibration element 14 may be comprised by cMUT etc. Further, it is desirable to fill a clogging material having acoustic isolation between the plurality of vibration elements 14 (gap in the two-dimensional array transducer 12).

  An ultrasonic beam is formed by the two-dimensional array transducer 12 and scanned electronically. Thereby, a plurality of two-dimensional data acquisition spaces (beam scanning planes), that is, three-dimensional data acquisition spaces are formed. As an electronic scanning method, an electronic sector scanning method or the like is known. On the upper side (biological side) of the two-dimensional array transducer 12, a matching layer 18 is provided via a ground electrode made of, for example, copper foil. The matching layer 18 may be configured by a plurality of matching elements aligned in the X direction and the Y direction. A plurality of matching layers 18 may be stacked. A protective layer or an acoustic lens is provided on the upper surface side of the matching layer 18 as necessary. Their upper surfaces constitute a wave transmitting / receiving surface. The wave transmitting / receiving surface is a surface that contacts the surface of the living body.

  A backing member 20 having a rectangular parallelepiped shape is provided on the back side (non-biological side) of the two-dimensional array transducer 12. The backing member 20 has a main body 22 that acts to absorb or attenuate unnecessary ultrasonic waves radiated from the two-dimensional array transducer 12 to the back surface side. The main body 22 is made of a material that exhibits a backing action. The backing member 20 according to the present embodiment is a lead backing that includes a plurality of leads 24.

  In the example shown in FIG. 1, the plurality of leads 24 are parallel to each other, and each lead 24 has a linear form. Each lead 24 is made of copper or other conductive material. Each lead 24 corresponds to a signal line (signal line) electrically connected to each corresponding vibration element 14. The plurality of leads 24 are two-dimensionally arranged in the X direction and the Y direction in the same arrangement as the plurality of vibration elements 14, and the plurality of leads 24 constitute a two-dimensional lead array.

  A signal processing layer is provided on the back side (the lower side in FIG. 1) of the backing member 20. In the specific example of FIG. 1, the signal processing layer has a structure in which a relay substrate 40 and an electronic circuit 50 are stacked. The relay substrate 40 is composed of a multilayer substrate, which exhibits an array conversion function and the like. One or more FPCs (not shown) are connected to the relay board 40. Each FPC has a signal line string connected to the electronic circuit 50. It is also possible to connect the electronic circuit 50 to the backing member 20 excluding the relay substrate 40. The electronic circuit 50 is configured as an IC, for example. The electronic circuit 50 exhibits a channel reduction function, generates a plurality of transmission signals, and processes a plurality of reception signals. The electronic circuit 50 desirably functions as a sub-beamformer.

  A plurality of lead electrodes electrically connected to the plurality of leads 24 are provided on the back surface (lower XY plane in FIG. 1) of the backing member 20. The plurality of lead electrodes are two-dimensionally arranged in the X direction and the Y direction in the same arrangement as the plurality of leads 24, and the plurality of lead electrodes constitute a two-dimensional lead electrode array. In addition, a plurality of signal electrodes are provided on the surface of the relay substrate 40 constituting the signal processing layer on the backing member 20 side (upper XY plane in FIG. 1). The plurality of signal electrodes are also two-dimensionally arranged in the X direction and the Y direction in the same arrangement as the plurality of leads 24, and the plurality of signal electrodes constitute a two-dimensional signal electrode array.

  The plurality of lead electrodes provided on the back surface of the backing member 20 and the plurality of signal electrodes provided on the surface of the relay substrate 40 are electrically connected through the plurality of bumps 30. The plurality of bumps 30 are disposed between the plurality of lead electrodes and the plurality of signal electrodes. The plurality of bumps 30 are also two-dimensionally arranged in the X direction and the Y direction in the same arrangement as the plurality of leads 24, and the plurality of bumps 30 constitute a two-dimensional bump array.

  A curing shrinkage material 34 is filled between the back surface of the backing member 20 and the surface of the relay substrate 40, and the backing member 20 and the relay substrate 40 are structurally connected by the curing shrinkage material 34. The structure (connection structure) of the connecting portion between the backing member 20 and the relay substrate 40 will be described in detail later.

  In the specific example of FIG. 1, a plurality of bumps such as solder are also provided between the relay substrate 40 and the electronic circuit 50, and further relayed by a curing shrinkage material filled between the relay substrate 40 and the electronic circuit 50. The substrate 40 and the electronic circuit 50 are structurally connected. In FIG. 1, the case that houses the vibrator assembly 10 is not shown.

  FIG. 2 is a view for explaining the structure of the connecting portion between the backing member 20 and the relay board 40. As shown in FIG. 1, a plurality of bumps 30 are provided between the backing member 20 and the relay substrate 40. An enlarged view of one of the plurality of bumps 30 and the vicinity thereof is shown in FIG.

  Each bump 30 electrically connects each lead electrode 26 provided on the back surface of the backing member 20 and each signal electrode 44 provided on the surface of the relay substrate 40. Each lead 24 is electrically connected to each vibration element 14 (FIG. 1), and each lead 24 and each lead electrode 26 are also electrically connected. Further, each lead electrode 26 and each signal electrode 44 are electrically connected by each bump 30. Thereby, a signal line (signal transmission path) from each vibration element 14 to each signal electrode 44 is formed.

  Each bump 30 is formed of a conductive material such as metal. Gold (Au) is suitable for the material of each bump 30. Further, a convex shape is suitable as the shape of each bump 30. In the specific example of FIG. 2, each bump 30 has an upwardly convex shape. In other words, each bump 30 in FIG. 2 has a convex shape that tapers on each lead electrode 26 side of the backing member 20 with each signal electrode 44 side of the relay substrate 40 as a base. Each bump 30 may be formed by one member, for example, by stacking a plurality of members that gradually become smaller from the lower side (each signal electrode 44 side) to the upper side (each lead electrode 26 side). May be.

  A conductive paste 32 is provided on each lead electrode 26 side of each bump 30. The conductive paste 32 desirably has an adhesive action. For example, an epoxy resin containing silver (Ag) is a preferred specific example. Each bump 30 and each lead electrode 26 come into contact with each other to realize electrical connection between each bump 30 and each lead electrode 26, and furthermore, each bump 30 and each lead electrode are formed by the conductive action and adhesive action of the conductive paste 32. 26 electrical connections are better.

  In the specific example of FIG. 2, the relay substrate 40 is formed of a multilayer substrate. Each substrate constituting the multilayer substrate is provided with a substrate conductor 46, and the substrate conductors 46 having different layers are electrically connected to each other through a via 48. The via 48 is, for example, a conductor such as copper (Cu) embedded in a through hole. Each signal electrode 44 is provided on the surface of the relay substrate 40, that is, on the surface of the uppermost substrate in the specific example of FIG.

  A curing shrinkage material 34 (underfill) is filled between the back surface of the backing member 20 and the surface of the relay substrate 40. The curing shrinkage material 34 is formed of, for example, an epoxy resin, and the curing shrinkage material 34 is heated to cure and shrink, whereby the backing member 20 and the relay substrate 40 are structurally connected. In order to protect the polarization of the piezoelectric body 14a (FIG. 1) provided on the backing member 20 side, it is desirable that the curing shrinkage material 34 be cured and shrunk at about 80 degrees Celsius. Further, for example, an acoustic damping filler or an acoustic scattering filler may be added to the curing shrinkage material 34. Thereby, the effect | action which absorbs or attenuates the ultrasonic wave which leaked from the back surface of the backing member 20 is exhibited.

  Each lead electrode 26 provided for each lead 24 is formed so as to spread in a region including directly under and corresponding to the corresponding lead 24. However, the adjacent lead electrodes 26 are electrically separated from each other, preferably structurally. In the specific example of FIG. 2, each lead electrode 26 and each bump 30 are connected immediately below each lead 24. Each bump 30 may not be directly under each lead 24 as long as it can be connected to the corresponding lead electrode 26 and is not connected to another lead electrode 26.

  Further, each bump 30 may be crushed while being in contact with the corresponding lead electrode 26 and electrically connected to the corresponding lead electrode 26, or may be pierced into the corresponding lead electrode 26 and connected to the lead electrode 26. It may be electrically connected.

  FIG. 3 is a diagram illustrating a specific example of the connection state of each bump 30. 3A to 3C show connection examples of the lead electrodes 26 and the signal electrodes 44 by the bumps 30. FIG. For example, each bump 30 is formed on each corresponding signal electrode 44 and then connected to each corresponding lead electrode 26. For example, in FIG. 3, corresponding lead electrodes 26 are connected to the bumps 30 from above the bumps 30.

FIG. 3A shows a specific example in which each corresponding lead electrode 26 and each signal electrode 44 are electrically connected in a state where the shape of each bump 30 is substantially maintained or completely maintained. In the specific example of FIG. 3A, the distance (height) from each signal electrode 44 to each lead electrode 26 is substantially the same h _A as the initial height of each bump 30.

On the other hand, FIG. 3B shows a specific example in which each bump 30 is crushed while being in contact with the corresponding lead electrode 26 to electrically connect the lead electrode 26 and the corresponding signal electrode 44. Show. In the specific example of FIG. 3B, the tip side of each bump 30, that is, the lead electrode 26 side is crushed, and the distance (height) from each signal electrode 44 to each lead electrode 26 is the initial height of each bump 30. H _B lower (smaller) than that. The height h _B by collapsing how each bump 30 is changed.

FIG. 3C shows a specific example in which each bump 30 pierces the corresponding lead electrode 26 and the lead electrode 26 and the corresponding signal electrode 44 are electrically connected. In the specific example of FIG. 3C, the tip side of each bump 30 is pierced into the lead electrode 26, and the distance (height) from each signal electrode 44 to each lead electrode 26 is higher than the initial height of each bump 30. It becomes lower (smaller) _{h C.} The height h _C changes depending on how each bump 30 is pierced. For example, the bumps 30 may be pierced into the lead electrode 26 while being crushed.

  3A to 3C, a conductive paste 32 (see FIG. 2 for omitting the illustration in FIG. 3) is provided on the side of each lead electrode 26 of each bump 30 so as to be conductive. Good electrical connection between each bump 30 and each lead electrode 26 is realized by the conductive action and adhesive action of the paste 32.

  As shown in the specific example shown in FIG. 3, the connection configuration in which the distance (height) from each signal electrode 44 to each lead electrode 26 changes according to the connection state of each bump 30 includes the back surface of the backing member 20 and the relay substrate. This is suitable in situations where it is difficult to make the 40 surfaces completely parallel. For example, it is suitable when the surface of the relay substrate 40 is warped with respect to the back surface of the backing member 20.

FIG. 4 is a diagram illustrating the warpage of the relay board 40. FIG. 4 shows a specific example of the relay board 40 that warps in a concave shape with respect to the backing member 20. In the specific example shown in FIG. 4, since the relay board 40 is warped in a concave shape, the distance (height) from the surface of the relay board 40 to the back surface of the backing member 20 becomes uneven in the plane. For example, the height of the central portion of the relay board 40 is h ₁ , whereas the height of the end portion of the backing member 20 is h ₃ (h ₃ <h ₁ ), which is an intermediate between the central portion and the end portion. In the portion, the height becomes h ₂ (h ₃ <h ₂ <h ₁ ). Therefore, the distance (height) between each signal electrode 44 (FIG. 2) provided on the surface of the relay substrate 40 and each lead electrode 26 (FIG. 2) provided on the back surface of the backing member 20 is also not uniform in the plane. Become.

  Therefore, in the specific example of FIG. 4, for example, when a plurality of lead electrodes 26 and a plurality of signal electrodes 44 are directly connected, each lead electrode 26 and each signal electrode 44 can be connected at the end portion of the backing member 20. Even so, a gap is generated between each lead electrode 26 and each signal electrode 44 in the central portion of the relay substrate 40, and electrical connection cannot be realized.

  In contrast, as described with reference to FIGS. 1 to 3, the plurality of lead electrodes 26 and the plurality of signal electrodes 44 are indirectly connected via a two-dimensional bump array including a plurality of bumps 30. By connecting, the non-uniform height between the plurality of lead electrodes 26 and the plurality of signal electrodes 44 can be absorbed by the two-dimensional bump array.

For example, the bumps 30 in the vicinity of the center of the relay substrate 40 (the portion of the height h ₁ in FIG. 4 and the vicinity thereof) substantially maintained the shape (height) as in the specific example of FIG. Each corresponding lead electrode 26 and each signal electrode 44 are electrically connected in a state. Further, the bumps 30 at the end near the backing member 20 (the portion and the vicinity thereof in the height h ₃ in FIG. 4), crushed as in example in FIG. 3 (B), or, 3 of (C) By piercing as in the specific example, each corresponding lead electrode 26 and each signal electrode 44 are electrically connected while changing its shape (height). Of course, specific examples of the bump 30 in (height h ₂ of the portion and its vicinity in example 4) the intermediate portion between the central portion and the end portion is also specific example or illustration of FIG. 3 (B) 3 (C) As described above, the corresponding lead electrode 26 and each signal electrode 44 are electrically connected while changing its shape (height).

  Therefore, even if the initial height of the plurality of bumps 30 constituting the two-dimensional bump array, that is, the height of the plurality of bumps 30 before being connected to the plurality of lead electrodes 26 is uniform, the plurality of leads The height of each bump 30 changes according to the connection state to the electrode 26 (see FIG. 3), and the non-uniform height between the plurality of lead electrodes 26 and the plurality of signal electrodes 44 is determined by the two-dimensional bump array. Can be absorbed.

  For example, even when the relay substrate 40 warps in a convex shape with respect to the backing member 20, the uneven height between the plurality of lead electrodes 26 and the plurality of signal electrodes 44 is absorbed by the two-dimensional bump array. be able to.

Further, the initial height of the plurality of bumps 30 may be varied. For example, if the warped relay substrate 40 is concave as in the embodiment shown in FIG. 4, according to the state of the warp, the bumps in the vicinity of the center (near the height h ₁ of the portion in FIG. 4) 30 may be formed relatively high from the beginning.

  FIG. 5 is a flowchart showing a specific example of the method for manufacturing the ultrasonic probe. Each process is demonstrated according to the flowchart of FIG. In addition, about the part (structure) which attached | subjected the code | symbol to FIGS. 1-4, the code | symbol of FIGS. 1-4 is utilized in the following description.

  In S501, the backing member 20 is manufactured. For example, a plurality of leads 24 electrically connected to the plurality of vibration elements 14 constituting the two-dimensional array transducer 12 are incorporated, and a plurality of lead electrodes 26 electrically connected to the plurality of leads 24 are provided on the back surface. The provided backing member 20 (see FIG. 1) is manufactured.

  In S502, the two-dimensional array transducer 12 is manufactured. For example, a laminated body of a hard backing (HB) 14b layer and a piezoelectric body 14a layer is formed on the living body side of the backing member 20 (upper side of the backing member 20 in FIG. 1), and the laminated body is two-dimensionally divided. Thus, a plurality of vibration elements 14 are formed.

  In this way, the vibrator stacked body in which the backing member 20 is provided on the back side of the two-dimensional array vibrator 12 is formed by the processes of S501 and S502. In forming the vibrator laminate, for example, a manufacturing method detailed in Patent Document 1 (Japanese Patent Laid-Open No. 2015-228932) may be used.

  In S503, the relay substrate 40 and the electronic circuit 50 are joined. For example, a plurality of solder bumps are provided between the relay substrate 40 and the electronic circuit 50, and further, a curing shrinkage material is filled between the relay substrate 40 and the electronic circuit 50, so that the relay substrate 40 and the electronic circuit 50 are structurally structured. Connected.

  In S <b> 504, the plurality of bumps 30 are formed on the plurality of signal electrodes 44 included in the relay substrate 40. For example, each signal electrode 44 side of the relay substrate 40 is used as a base, and each tapered bump-shaped bump 30 is formed on the tip side (upper side in FIG. 2).

  Thus, the signal processing layer in which the plurality of bumps 30 are provided on the surface of the relay substrate 40 is formed by the processes of S503 and S504.

  In S505, the conductive paste is applied to the front end side (upper side in FIG. 2) of the plurality of bumps 30, and then the back side of the backing member 20 and the surface side of the relay substrate 40 are joined in S506. In the bonding of S506, the backing member 20 and the relay substrate 40 are aligned so that each bump 30 and each corresponding lead electrode 26 are in contact with each other, and the plurality of lead electrodes 26 provided on the back surface of the backing member 20 are relayed. A plurality of signal electrodes 44 provided on the surface of the substrate 40 are electrically connected via a plurality of bumps 30.

  After that, in S507, the space between the back surface of the backing member 20 and the surface of the relay substrate 40 is filled with the curing shrinkage material 34 (underfill), and the curing shrinkage material 34 is heated and cured and contracted, whereby the backing member 20 and The relay board 40 is structurally connected.

  In the flowchart of FIG. 5, the signal processing layer may be manufactured (S503, S504) before the manufacture of the vibrator stack (S501, S502), or at least part of the manufacture of the vibrator stack. And at least part of the fabrication of the signal processing layer may be performed simultaneously.

  As mentioned above, although preferred embodiment of this invention was described, embodiment mentioned above is only a mere illustration in all the points, and does not limit the scope of the present invention. The present invention includes various modifications without departing from the essence thereof.

  10 transducer assemblies, 12 two-dimensional array transducers, 14 transducer elements, 20 backing members, 24 leads, 26 lead electrodes, 30 bumps, 40 relay boards, 44 signal electrodes, 50 electronic circuits.

Claims (8)

A two-dimensional array transducer comprising a plurality of transducer elements arranged two-dimensionally;
A backing member provided on the back side of the two-dimensional array transducer, and comprising a plurality of leads electrically connected to the plurality of vibration elements;
A plurality of lead electrodes provided on the back surface of the backing member and electrically connected to the plurality of leads;
A substrate having a surface on the backing member side and provided with a plurality of signal electrodes on the surface ; and an electric circuit connected to the back surface of the substrate by a curing shrinkage material;
Provided on said plurality of signal electrodes, a plurality of bumps for electrically connecting the front Symbol plurality of lead electrodes and the previous SL plurality of signal electrodes,
I have a,
The surface of the substrate is warped, whereby the distance between the plurality of lead electrodes and the plurality of signal electrodes changes from a central portion to an end portion of the substrate,
The height of the plurality of bumps is changed in accordance with a change in the distance between the plurality of lead electrodes and the plurality of signal electrodes.
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1 ,
Wherein each of the bumps, the a convex tapered to the lead electrode side,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1 ,
Wherein at least one of the plurality of bumps are electrically connected pierced to the lead electrodes in contact therewith to those 該Ri over cathode electrode,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1 ,
Wherein at least one of the plurality of bumps are electrically connected to the press and crushed by those 該Ri over cathode electrode to the lead electrodes in contact therewith,
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1 ,
A conductive paste provided on each lead electrode side of each bump and electrically connecting each bump and each lead electrode;
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 1 ,
A curing shrinkage material that is filled between the back surface of the backing member and the surface of the signal processing layer and that structurally connects the backing member and the substrate ;
An ultrasonic probe characterized by that. The ultrasonic probe according to claim 6 ,
The curing shrinkage material is a resin to which at least one of an acoustic attenuation filler and an acoustic scattering filler is added,
An ultrasonic probe characterized by that. Built a plurality of leads that are electrically connected to the plurality of vibration elements constituting the two-dimensional array transducer, and a backing member having a plurality of lead electrodes electrically connected to the plurality of leads on the back surface. And a process of
A step of providing a plurality of signal electrodes to the surface of the substrate,
Bonding an electric circuit to the back surface of the substrate with a curing shrinkable material ;
Forming a plurality of bumps having a uniform height on the surface of the plurality of signal electrodes;
Bonding the plurality of lead electrodes and the plurality of signal electrodes via the plurality of bumps ;
Have
In the bonding step, the surface of the substrate is warped, and the height of the plurality of bumps becomes non-uniform due to the contact of the plurality of bumps with the plurality of lead electrodes.
An ultrasonic probe manufacturing method characterized by the above.

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