Ultrasonic probe and method for manufacturing ultrasonic probe

Abstract

This ultrasonic probe comprises: a plurality of ultrasonic transducers arrayed along an array direction; a plurality of signal cables electrically respectively connected to the ultrasonic transducers; and a substrate electrically connecting the ultrasonic transducers and the signal cables. The substrate has: a conductive layer in which a prescribed interconnection pattern is formed; and an insulating layer formed from an insulating material and provided on the opposite side of the conductive layer from the ultrasonic transducers. In the insulating layer, a vibration damping part formed from a material having a different acoustic impedance from the insulating layer is provided between adjacent ultrasonic transducers along the array direction. This allows for a reduction in acoustic crosstalk caused by ultrasonic vibrations propagating through the substrate.

Description

Ultrasonic Probe and Method for Manufacturing Ultrasonic Probe 【0001】 The present invention relates to an ultrasonic probe and a method for manufacturing an ultrasonic probe. 【0002】 Conventionally, an ultrasonic probe including a plurality of ultrasonic transducers that each emit ultrasonic waves in response to an input electrical signal is known. Also known is an ultrasonic probe including a flexible substrate on which wiring for electrically connecting the plurality of ultrasonic transducers is formed. 【0003】 In an ultrasonic probe, acoustic crosstalk is known in which ultrasonic waves emitted by a certain ultrasonic transducer affect adjacent ultrasonic transducers. Patent Document 1 describes filling a groove that element-separates transducers in a strip shape with a predetermined resin in which a material with low acoustic crosstalk in a micro-balloon shape is mixed. 【0004】 Japanese Patent Application Laid-Open No. 2000-115871 【0005】 In an ultrasonic probe including a substrate, ultrasonic vibrations may propagate through the substrate, resulting in acoustic crosstalk. 【0006】 The present invention has been made in view of the above, and an object thereof is to provide an ultrasonic probe and a method for manufacturing an ultrasonic probe that can reduce acoustic crosstalk caused by ultrasonic vibrations propagating through a substrate. 【0007】 In order to solve the above-described problems and achieve the object, an ultrasonic probe according to an aspect of the present invention includes a plurality of ultrasonic transducers arranged along an array direction, a plurality of signal cables electrically connected to each of the ultrasonic transducers, and a substrate electrically connecting the ultrasonic transducers and the signal cables. The substrate has a conductive layer in which a predetermined wiring pattern is formed, and an insulating layer provided on the opposite side of the conductive layer from the ultrasonic transducers and made of an insulating material. In the insulating layer, a vibration damping portion made of a material having a different acoustic impedance from that of the insulating layer is provided between the ultrasonic transducers adjacent along the array direction. 【0008】Furthermore, in one aspect of the present invention, the ultrasonic probe comprises at least one conductive layer comprising two or more conductive layers, and at least one insulating layer comprising two or more insulating layers, and the substrate is arranged such that the two or more conductive layers and the two or more insulating layers are alternately laminated. 【0009】 Furthermore, in one embodiment of the present invention, the vibration damping portion is provided in all of the insulating layers of the ultrasonic probe. 【0010】 Furthermore, in one embodiment of the present invention, the vibration damping portion is provided in any of the insulating layers of the ultrasonic probe. 【0011】 Furthermore, in one aspect of the present invention, the ultrasonic probe has a vibration damping section in which the length of each insulating layer differs in the direction of arrangement. 【0012】 Furthermore, in an ultrasonic probe according to one aspect of the present invention, the vibration damping portion has a longer length in the arrangement direction as the insulating layer moves further away from the ultrasonic transducer. 【0013】 Furthermore, in one aspect of the present invention, the ultrasonic probe is such that the vibration damping portion is a gap formed on or inside the insulating layer. 【0014】 Furthermore, in one aspect of the present invention, the ultrasonic probe is formed by adding bubbles or fillers to the surface or interior of the insulating layer. 【0015】 Furthermore, in one aspect of the present invention, the ultrasonic probe is formed by filling the surface or interior of the insulating layer with a material that has a different acoustic impedance from the insulating layer. 【0016】 Furthermore, an ultrasonic probe according to one aspect of the present invention includes an insertion portion that is inserted into a subject, the ultrasonic transducer and the substrate are arranged on the tip side of the insertion portion, and the signal cable extends from the substrate to the base end side of the insertion portion. 【0017】 Furthermore, an ultrasonic probe according to one aspect of the present invention includes an image sensor positioned at the tip of the insertion portion for imaging the inside of the subject. 【0018】Furthermore, a method for manufacturing an ultrasonic probe according to one aspect of the present invention involves forming a vibration damping portion on or inside an insulating layer made of an insulating material, forming a conductive layer by forming a predetermined wiring pattern on the insulating layer, laminating a laminate containing a piezoelectric material on the conductive layer, and separating the piezoelectric material into a plurality of ultrasonic transducers arranged along the arrangement direction. 【0019】 Furthermore, in a method for manufacturing an ultrasonic probe according to one aspect of the present invention, the vibration damping portion is located between adjacent ultrasonic transducers along the arrangement direction and is made of a material with a different acoustic impedance from the insulating layer. 【0020】 Furthermore, in a method for manufacturing an ultrasonic probe according to one aspect of the present invention, the vibration damping portion is formed by forming a gap on or inside the insulating layer. 【0021】 Furthermore, in a method for manufacturing an ultrasonic probe according to one aspect of the present invention, the vibration damping portion is formed by adding bubbles or fillers to the surface or interior of the insulating layer. 【0022】 Furthermore, in a method for manufacturing an ultrasonic probe according to one aspect of the present invention, the vibration damping portion is formed by creating a gap on the surface or inside the insulating layer and filling it with a material that has a different acoustic impedance from the insulating layer. 【0023】 Furthermore, an ultrasonic probe according to one aspect of the present invention comprises a plurality of ultrasonic transducers arranged along the arrangement direction, a plurality of signal cables electrically connected to each of the ultrasonic transducers, and a substrate electrically connecting the ultrasonic transducers and the signal cables, wherein the substrate has a conductive layer on which a predetermined wiring pattern is formed, and an insulating layer made of an insulating material provided on the side of the conductive layer opposite to the ultrasonic transducers, and the insulating layer is provided with vibration damping portions which are gaps formed on the surface or inside the insulating layer between adjacent ultrasonic transducers along the arrangement direction. 【0024】 According to the present invention, it is possible to realize an ultrasonic probe that can reduce acoustic crosstalk caused by ultrasonic vibrations propagating through a substrate, and a method for manufacturing an ultrasonic probe. 【0025】Figure 1 is a schematic diagram showing an ultrasonic probe according to an embodiment. Figure 2 is a perspective view showing the tip of the insertion part. Figure 3 is a cross-sectional view showing the ultrasonic probe. Figure 4 is a cross-sectional view showing an ultrasonic transducer and a substrate. Figure 5 is a top view of the substrate. Figure 6 is a diagram showing the preparation of a plurality of conductive layers and a plurality of insulating layers. Figure 7 is a flowchart showing the manufacturing method of the ultrasonic probe. Figure 8 is a diagram showing the formation of the vibration damping section. Figure 9 is a diagram showing the stacking of each layer. Figure 10 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 1. Figure 11 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 2. Figure 12 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 3. Figure 13 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 4. Figure 14 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 5. Figure 15 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 6. Figure 16 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 7. Figure 17 is a cross-sectional view showing an ultrasonic transducer and a substrate according to Modification 8. Figure 18 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 9. Figure 19 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 10. Figure 20 is a top view of a substrate according to Modification 11. Figure 21 is a top view of a substrate according to Modification 12. 【0026】 Embodiments of the ultrasonic probe and method for manufacturing the ultrasonic probe according to the present invention will be described below with reference to the drawings. However, the present invention is not limited to these embodiments. The present invention can be applied in general to ultrasonic probes comprising a substrate and methods for manufacturing ultrasonic probes. 【0027】 Furthermore, in the drawings, identical or corresponding elements are appropriately denoted by the same reference numeral. It should also be noted that the drawings are schematic, and the dimensional relationships and proportions of each element may differ from reality. Even between drawings, there may be differences in dimensional relationships and proportions. 【0028】(Embodiment) [Configuration of Endoscopic System] Figure 1 is a schematic diagram showing an ultrasound probe according to an embodiment. The endoscopy system 1 is a system that performs ultrasound diagnosis and treatment inside a subject such as a human using an ultrasound endoscope. As shown in Figure 1, this endoscopy system 1 comprises an ultrasound endoscope 2, an ultrasound observation device 3, an endoscopy observation device 4, and a display device 5. 【0029】 The ultrasound endoscope 2 is partially insertable into the subject and has the function of transmitting ultrasound pulses (acoustic pulses) toward the body wall inside the subject and receiving ultrasound echoes reflected by the subject to output an echo signal, as well as the function of outputting an image signal by imaging the inside of the subject. The detailed configuration of the ultrasound endoscope 2 will be described later. 【0030】 The ultrasound observation device 3 is electrically connected to the ultrasound endoscope 2 via an ultrasound cable 31 (Figure 1). The ultrasound observation device 3 outputs a pulse signal to the ultrasound endoscope 2 via the ultrasound cable 31, and the ultrasound endoscope 2 outputs an echo signal. The ultrasound observation device 3 then generates an ultrasound image by performing predetermined processing on the echo signal. 【0031】 The endoscopic observation device 4 is detachably connected to the endoscopic connector 9 (Figure 1), which will be described later, of the ultrasonic endoscope 2. As shown in Figure 1, the endoscopic observation device 4 includes a video processor 41 and a light source device 42. 【0032】 The video processor 41 receives image signals from the ultrasound endoscope 2 via the endoscope connector 9. The video processor 41 then generates an endoscopic image by performing predetermined processing on the image signals. 【0033】 The light source device 42 supplies illumination light to the ultrasound endoscope 2 via the endoscope connector 9 to illuminate the inside of the subject. 【0034】The display device 5 is configured using liquid crystal, organic EL (Electro Luminescence), CRT (Cathode Ray Tube), or a projector, and displays ultrasound images generated by the ultrasound observation device 3, endoscopic images generated by the endoscope observation device 4, and the like. 【0035】 [Configuration of the Ultrasound Endoscope] Next, the configuration of the ultrasound endoscope 2 will be described. As shown in Figure 1, the ultrasound endoscope 2 comprises an insertion section 6, an operating section 7, a universal cord 8, and an endoscope connector 9. Figure 2 is a perspective view showing the tip of the insertion section. 【0036】 In the following explanation of the structure of the insertion portion 6, the tip side of the insertion portion 6 (the tip side in the direction of insertion into the subject) will be referred to only as the "tip side," and the proximal end side of the insertion portion 6 (the side that is separated from the tip of the insertion portion 6) will be referred to only as the "proximal end side." 【0037】 The insertion portion 6 is the part that is inserted into the subject. As shown in Figure 1 or Figure 2, the insertion portion 6 comprises an ultrasonic probe 10 provided at the tip end, a rigid member 61 connected to the base end of the ultrasonic probe 10, a bendable portion 62 connected to the base end of the rigid member 61, and a flexible tube 63 (Figure 1) connected to the base end of the bendable portion 62 and having flexibility. 【0038】 Furthermore, inside the insertion section 6, the operating section 7, the universal cord 8, and the endoscope connector 9, there are routed light guides (not shown) for transmitting illumination light supplied from the light source device 42, transducer cables 12 (see Figure 3) for transmitting the aforementioned pulse signals and echo signals, and signal cables (not shown) for transmitting image signals, as well as conduits (not shown) for the flow of fluid. 【0039】 Here, the rigid member 61 is a rigid member made of a resin material or the like, and has a substantially cylindrical shape that extends along the insertion axis Ax (Figure 2). The insertion axis Ax is an axis that runs along the direction of extension of the insertion portion 6. On the outer circumferential surface of the rigid member 61 at the tip end, an inclined surface 611 is formed, which makes the rigid member 61 tapered towards the tip. 【0040】And, as shown in FIG. 2, the rigid member 61 is formed with a mounting hole (not shown) penetrating from the proximal end to the distal end, illumination holes 612 penetrating from the proximal end to the inclined surface 611, imaging holes 613, air and water supply holes 614, a treatment instrument channel 615, etc. The above-described mounting hole (not shown) is a hole for mounting the ultrasonic probe 10. And, the vibrator cable 12 (see FIG. 3) is inserted inside the mounting hole. 【0041】 Inside the illumination hole 612, the emission end side of the above-described light guide (not shown) and an illumination lens 616 (FIG. 2) for irradiating the illumination light emitted from the emission end of the light guide toward the subject inside the body are disposed. 【0042】 Inside the imaging hole 613, an objective optical system 617 (FIG. 2) for collecting light (subject image) irradiated toward the subject inside the body and reflected inside the subject, and an imaging element (not shown) for imaging the subject image collected by the objective optical system 617 are disposed. That is, the imaging element is disposed on the distal end side of the insertion portion 6 and images the inside of the subject's body. And, the image signal imaged by the imaging element is transmitted to the endoscope observation device 4 (video processor 41) via the above-described signal cable (not shown). 【0043】 In the first embodiment, as described above, the illumination hole 612 and the imaging hole 613 are formed in the inclined surface 611. For this reason, the ultrasonic endoscope 2 according to the first embodiment is configured as a perspective type endoscope that observes in a direction intersecting the insertion axis Ax at an acute angle. 【0044】 The air and water supply hole 614 constitutes a part of the above-described pipeline (not shown), and is a hole for supplying air or water toward the imaging hole 613 to wash the outer surface of the objective optical system 617. 【0045】 The treatment instrument channel 615 is a passage for protruding a treatment instrument (not shown) such as a puncture needle inserted inside the insertion portion 6 to the outside. 【0046】The operation unit 7 is connected to the proximal end side of the insertion unit 6 and is a part that receives various operations from a doctor or the like. As shown in FIG. 1, this operation unit 7 includes a bending knob 71 for bending the bending unit 62 and a plurality of operation members 72 for performing various operations. 【0047】 In addition, the operation unit 7 communicates with the treatment tool channel 615 via a tube (not shown) provided inside the bending unit 62 and the flexible tube 63, and a treatment tool insertion port 73 (FIG. 1) for inserting a treatment tool (not shown) into the tube is provided. 【0048】 The universal cord 8 extends from the operation unit 7, and a tube (not shown) in which a light guide (not shown), a vibrator cable 12, a signal cable (not shown), and a part of the above-described pipeline (not shown) are arranged is disposed. 【0049】 The endoscope connector 9 is provided at the end of the universal cord 8. The endoscope connector 9 is connected to the ultrasonic cable 31 and is inserted into the endoscope observation device 4 to connect to the video processor 41 and the light source device 42. 【0050】 〔Configuration of Ultrasonic Probe〕Next, the configuration of the ultrasonic probe 10 will be described. FIG. 3 is a cross-sectional view showing the ultrasonic probe. Specifically, FIG. 3 is a cross-sectional view of the ultrasonic probe 10 cut in a plane orthogonal to the scanning surface SS including the insertion axis Ax. The ultrasonic probe 10 is a convex type ultrasonic probe and has a cylindrical scanning surface SS that is convex toward the outside (upper side in FIG. 3). 【0051】 As shown in FIG. 3, the ultrasonic probe 10 includes an ultrasonic transducer 11, a vibrator cable 12, a substrate 13, an acoustic lens 14, an acoustic matching layer 15, a back layer 16, a ground wire 17, and a housing 18. 【0052】 As shown in FIG. 3, the ultrasonic transducer 11 includes a plurality of ultrasonic vibrators 111. The plurality of ultrasonic vibrators 111 are arranged on the distal end side of the insertion unit 6. 【0053】Each of the multiple ultrasonic transducers 111 is composed of a long rectangular parallelepiped extending linearly along a direction perpendicular to the plane of the paper in Figure 3, and is regularly arranged along the arrangement direction as shown in Figure 3. The ultrasonic transducers 111 convert the input pulse signal (corresponding to the electrical signal according to the present invention) into ultrasonic pulses via the transducer cable 12 and the substrate 13, and transmit them to the subject. The ultrasonic transducers 111 also convert the ultrasonic echo reflected by the subject into an electrical echo signal and output it to the transducer cable 12 via the substrate 13. 【0054】 The ultrasonic transducer 111 is formed using PMN-PT single crystal, PMN-PZT single crystal, PZN-PT single crystal, PIN-PZN-PT single crystal, or a relaxer material. PMN-PT single crystal is an abbreviation for a solid solution of magnesium, lead niobate, and lead titanate. PMN-PZT single crystal is an abbreviation for a solid solution of magnesium, lead niobate, and lead zirconate titanate. PZN-PT single crystal is an abbreviation for a solid solution of zinc, lead niobate, and lead titanate. PIN-PZN-PT single crystal is an abbreviation for a solid solution of indium, lead niobate, zinc, lead niobate, and lead titanate. Relaxer materials are a general term for ternary piezoelectric materials in which lead-based composite perovskite, a relaxer material, is added to lead zirconate titanate (PZT) for the purpose of increasing the piezoelectric constant and dielectric constant. Lead-based composite perovskites are Pb(B1,B2)O ３ It is represented by B1 being magnesium, zinc, indium, or scandium, and B2 being niobium, tantalum, or tungsten. 【0055】 The transducer cable 12 has a plurality of signal cables 121 that are electrically connected to each of the plurality of ultrasonic transducers 111. The plurality of signal cables 121 extend from the substrate 13 towards the base end of the insertion portion 6. 【0056】 The substrate 13 electrically connects the ultrasonic transducer 111 and the signal cable 121. The substrate 13 is a flexible substrate made of a resin such as polyimide. The substrate 13 is located at the tip end of the insertion section 6. 【0057】The acoustic lens 14 is formed using silicone, polymethylpentene, epoxy resin, polyetherimide, etc., and has one surface that is convex or concave to focus the ultrasonic waves, thereby emitting the ultrasonic waves that have passed through the acoustic matching layer 15 to the outside, or taking in ultrasonic echoes from the outside. The acoustic lens 14 can be provided as desired, and the system may also be configured without an acoustic lens 14. 【0058】 The acoustic matching layer 15 is positioned relative to the ultrasonic transducers 111 in the direction in which each ultrasonic transducer 111 transmits ultrasound. The acoustic matching layer 15 matches the acoustic impedance between the ultrasonic transducers 111 and the object being observed in order to efficiently transmit sound (ultrasound) between the ultrasonic transducers 111 and the object being observed. The acoustic matching layer 15 may be a single layer or it may be two or more layers. Furthermore, depending on the characteristics of the ultrasonic transducers 111 and the object being observed, an acoustic matching layer may not be provided. 【0059】 The back layer 16 is laminated on the side of the ultrasonic transducer 111 opposite to the acoustic matching layer 15, and is a dematching layer that reflects at least a portion of the unwanted ultrasonic waves generated by the operation of the ultrasonic transducer 111, or a backing material that attenuates the unwanted ultrasonic waves generated by the operation of the ultrasonic transducer 111. Depending on the characteristics of the ultrasonic transducer 111 and the object being observed, the back layer may not be provided. 【0060】 The ground wire 17 electrically connects the ultrasonic transducer 111 to the ground wire of the transducer cable 12. 【0061】 The housing 18 accommodates multiple ultrasonic transducers 11 and substrates 13. 【0062】 Figure 4 is a cross-sectional view showing the ultrasonic transducer and the substrate. In the following description of the substrate 13, the upper surface of the substrate 13 (the side facing the ultrasonic transducer 111) will be referred to only as the "top surface," and the lower surface of the substrate 13 (the side opposite the ultrasonic transducer 111) will be referred to only as the "bottom surface." 【0063】As shown in Figure 4, the substrate 13 is located below the ultrasonic transducer 111 and has a first conductive layer 131, a first insulating layer 132, a second conductive layer 133, a second insulating layer 134, a third conductive layer 135, and a third insulating layer 136. That is, the substrate 13 has a plurality of alternately stacked conductive layers (first conductive layer 131, second conductive layer 133, and third conductive layer 135) and a plurality of insulating layers (first insulating layer 132, second insulating layer 134, and third insulating layer 136). The first conductive layer 131, first insulating layer 132, second conductive layer 133, second insulating layer 134, third conductive layer 135, and third insulating layer 136 are stacked in this order from the ultrasonic transducer 111 side. 【0064】 A predetermined wiring pattern is formed on the first conductive layer 131, the second conductive layer 133, and the third conductive layer 135. The first conductive layer 131 transmits and receives electrical signals to and from each ultrasonic transducer 111. The wirings of the first conductive layer 131, the second conductive layer 133, and the third conductive layer 135 are electrically connected by vias or the like. 【0065】 The first insulating layer 132, the second insulating layer 134, and the third insulating layer 136 are provided on the opposite side (lower side in Figure 4) of the first conductive layer 131, the second conductive layer 133, and the third conductive layer 135 from the ultrasonic transducer 111, respectively. The first insulating layer 132, the second insulating layer 134, and the third insulating layer 136 are made of an insulating material such as polyimide. 【0066】 The first insulating layer 132, the second insulating layer 134, and the third insulating layer 136 are provided with vibration damping sections 132a, 134a, and 136a, respectively. In other words, all insulating layers (the first insulating layer 132, the second insulating layer 134, and the third insulating layer 136) are provided with vibration damping sections (vibration damping sections 132a, 134a, and 136a). 【0067】The vibration damping sections 132a, 134a, and 136a are provided between adjacent ultrasonic transducers 111 along the alignment direction (left-right direction in Figure 4). The vibration damping sections 132a, 134a, and 136a are made of materials with different acoustic impedances from the first insulating layer 132, the second insulating layer 134, and the third insulating layer 136. Specifically, the vibration damping sections 132a, 134a, and 136a are gaps formed on the back surface of the first insulating layer 132, the second insulating layer 134, and the third insulating layer 136. 【0068】 Figure 5 is a top view of the substrate. As shown in Figure 5, the wiring pattern of the first conductive layer 131 extends along the longitudinal direction of the ultrasonic transducer 111 (up and down direction in Figure 5). The wiring pattern of the second conductive layer 133 extends in the alignment direction of the ultrasonic transducer 111 (left and right direction in Figure 5). In contrast, the vibration damping portion 132a formed in the first insulating layer 132 extends along the longitudinal direction of the ultrasonic transducer 111 (up and down direction in Figure 5). 【0069】 [Method for Manufacturing an Ultrasonic Probe] Next, the method for manufacturing an ultrasonic probe will be described. Figure 6 shows the preparation of multiple conductive layers and multiple insulating layers. As shown in Figure 6, a first insulating layer 132, a laminated second conductive layer 133 and a second insulating layer 134, and a laminated third conductive layer 135 and a third insulating layer 136 are prepared. The second conductive layer 133 and the third conductive layer 135 have predetermined wiring patterns formed on them in advance. 【0070】 Figure 7 is a flowchart showing the method for manufacturing an ultrasonic probe. Figure 8 shows the process of forming the vibration damping section. As shown in Figure 8, vibration damping sections 132a, 134a, and 136a, which are gaps, are formed on the lower surfaces of the first insulating layer 132, the second insulating layer 134, and the third insulating layer 136 (step S1). 【0071】 Next, a first conductive layer 131 with a predetermined wiring pattern is formed on the first insulating layer 132 (step S2). 【0072】Figure 9 shows the process of stacking each layer. As shown in Figure 9, the first conductive layer 131 to the third insulating layer 136 are stacked to form a substrate 13, and a laminate containing a piezoelectric material is stacked on the substrate 13 (step S3). 【0073】 Subsequently, the piezoelectric material is separated into a plurality of ultrasonic transducers 111 arranged along the direction of arrangement (step S4). 【0074】 As described above, since vibration damping sections 132a, 134a, and 136a are formed in the first insulating layer 132, the second insulating layer 134, and the third insulating layer 136, acoustic crosstalk caused by ultrasonic vibrations propagating through the substrate 13 can be reduced. 【0075】 (Modification 1) Figure 10 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 1. As shown in Figure 10, the first insulating layer 132A, the second insulating layer 134A, and the third insulating layer 136A of the substrate 13A are provided with vibration damping sections 132Aa, 134Aa, and 136Aa, respectively. The vibration damping sections 132Aa, 134Aa, and 136Aa each have different lengths in the direction of arrangement. 【0076】 As shown in Modification 1, the length of the vibration damping section in the alignment direction may differ for each insulating layer. Depending on the distance between the ultrasonic transducers 111 and the thickness of each layer of the substrate, the length of the vibration damping section in the alignment direction for each insulating layer can be set to reduce acoustic crosstalk. 【0077】 (Modification 2) Figure 11 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 2. As shown in Figure 11, the first insulating layer 132B, the second insulating layer 134B, and the third insulating layer 136B of the substrate 13B are provided with vibration damping sections 132Ba, 134Ba, and 136Ba, respectively. The length of the vibration damping sections 132Ba, 134Ba, and 136Ba in the arrangement direction is longer for insulating layers that are further away from the ultrasonic transducer 111. 【0078】 As shown in Modification 2, acoustic crosstalk may be reduced by increasing the length of the vibration damping section in the direction of arrangement of the insulating layer that is further away from the ultrasonic transducer 111. 【0079】 (Modification 3) Figure 12 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 3. As shown in Figure 12, the first insulating layer 132C, the second insulating layer 134C, and the third insulating layer 136C of the substrate 13C are provided with vibration damping portions 132Ca, 134Ca, and 136Ca, respectively. A portion of the vibration damping portion 134Ca has a long length in the direction of arrangement. 【0080】 As shown in Modification 3, by increasing the length in the direction of the arrangement of the vibration damping portion of the intermediate insulating layer, the ultrasonic waves returning from the bottom side may be reduced, thereby reducing acoustic crosstalk. 【0081】 (Modification 4) Figure 13 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 4. As shown in Figure 13, the first insulating layer 132D, the second insulating layer 134D, and the third insulating layer 136D of the substrate 13D are provided with vibration damping sections 132Da, 134Da, and 136D, respectively. The vibration damping sections 132Da, 134Da, and 136D are arranged in a staggered pattern, alternating between adjacent ultrasonic transducers 111 along the arrangement direction, with one section at a time. 【0082】 As shown in Modification 4, acoustic crosstalk may be reduced by arranging the vibration damping sections in a staggered pattern. 【0083】 (Modification 5) Figure 14 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 5. As shown in Figure 14, vibration damping sections 132Ea, 134Ea, and 136Ea are provided in the first insulating layer 132E, the second insulating layer 134E, and the third insulating layer 136E of the substrate 13E, respectively. The vibration damping sections 132Ea, 134Ea, and 136Ea are provided alternately between adjacent ultrasonic transducers 111 along the arrangement direction. 【0084】 As shown in Modification 5, acoustic crosstalk may be reduced by arranging vibration damping units every other unit. 【0085】(Modification 6) Figure 15 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 6. As shown in Figure 15, the first insulating layer 132F, the second insulating layer 134F, and the third insulating layer 136F of the substrate 13F are provided with vibration damping sections 132Fa, 134Fa, and 136F, respectively. The vibration damping sections 132Fa, 134Fa, and 136F are formed by adding bubbles or fillers to the lower surface of the insulating layer. 【0086】 As shown in Modification 6, vibration damping sections may be formed by adding air bubbles or fillers to reduce acoustic crosstalk. 【0087】 (Modification 7) Figure 16 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 7. As shown in Figure 16, the first insulating layer 132G, the second insulating layer 134G, and the third insulating layer 136G of the substrate 13G are provided with vibration damping sections 132Ga, 134Ga, and 136Ga, respectively. The vibration damping sections 132Ga, 134Ga, and 136Ga are formed by creating a gap on the lower surface of the insulating layer and filling it with a material that has a different acoustic impedance from the insulating layer. Examples of the filling material include epoxy resin, glass beads, urethane, sponge, foamed urethane, cotton, etc. 【0088】 As shown in Modification 7, a vibration damping section may be formed by filling the insulating layer with a material having a different acoustic impedance, thereby reducing acoustic crosstalk. 【0089】 (Modification 8) Figure 17 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 8. As shown in Figure 17, the first insulating layer 132H, the second insulating layer 134H, and the third insulating layer 136H of the substrate 13H are provided with vibration damping sections 132Ha, 134Ha, and 136Ha, respectively. The vibration damping sections 132Ha, 134Ha, and 136Ha are provided inside the insulating layers. 【0090】 As shown in Modification 8, the vibration damping portion may be formed inside the insulating layer. 【0091】(Modification 9) Figure 18 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 9. As shown in Figure 18, the first insulating layer 132I, the second insulating layer 134I, and the third insulating layer 136I of the substrate 13I are provided with vibration damping sections 132Ia, 134Ia, and 136Ia, respectively. The vibration damping sections 132Ia, 134Ia, and 136Ia are provided on the upper surface of the insulating layer. 【0092】 As shown in Modification 9, the vibration damping portion may be formed on the upper surface side of the insulating layer. 【0093】 (Modification 10) Figure 19 is a cross-sectional view showing an ultrasonic transducer and substrate according to Modification 10. As shown in Figure 19, the second insulating layer 134J of the substrate 13J is provided with a vibration damping section 134Ja. On the other hand, the first insulating layer 132J and the third insulating layer 136J are not provided with vibration damping sections. 【0094】 As shown in modified example 10, vibration damping sections may be provided only in some of the insulating layers. 【0095】 (Modification 11) Figure 20 is a top view of the substrate according to Modification 11. As shown in Figure 20, the first insulating layer 132K of the substrate 13K is provided with vibration damping sections 132Ka. The vibration damping sections 132Ka are located between the ultrasonic transducers 111 in the longitudinal direction of the ultrasonic transducers 111 and between the second conductive layers 133 in the arrangement direction. 【0096】 As shown in modified example 11, the vibration damping section of the ultrasonic transducer 111 does not have to be continuous in the longitudinal direction. 【0097】 (Modification 12) Figure 21 is a top view of the substrate according to Modification 12. As shown in Figure 21, vibration damping sections 132La are provided in the first insulating layer 132L of the substrate 13L. The vibration damping sections 132La are provided alternately in a staggered pattern between the ultrasonic transducers 111 in the longitudinal direction of the ultrasonic transducer 111 and between the second conductive layer 133 in the arrangement direction. 【0098】 As shown in modified example 12, it is not necessary for vibration damping sections to be formed between all ultrasonic transducers 111. 【0099】 Further effects and modifications can be readily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the specific details and representative embodiments expressed and described above. Accordingly, various modifications are possible without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents. 【0100】1 Endoscope system 2 Ultrasonic endoscope 3 Ultrasonic observation device 4 Endoscope observation device 5 Display device 6 Insertion section 7 Operating section 8 Universal cord 9 Endoscope connector 10 Ultrasonic probe 11 Ultrasonic transducer 12 Transducer cable 13, 13A, 13B, 13C, 13D, 13E, 13F, 13G, 13H, 13I, 13J, 13K, 13L Substrate 14 Acoustic lens 15 Acoustic matching layer 16 Back layer 17 Ground wire 18 Housing 31 Ultrasonic cable 41 Video processor 42 Light source device 61 Rigid member 62 Bending section 63 Flexible tube 71 Bending knob 72 Operating member 73 Instrument insertion port 111 Ultrasonic transducer 121 Signal cable 131 First conductive layer 132, 132A, 132B, 132C, 132D, 132E, 132F, 132G, 132H, 132I, 132J, 132K, 132L First insulating layer 132a, 134a, 136a, 132Aa, 134Aa, 136Aa, 132Ba, 134Ba, 136Ba, 132Ca, 134Ca, 136Ca, 132Da, 134Da, 136Da, 132Ea, 134Ea, 136Ea, 132Fa, 134Fa, 136Fa, 132Ga, 134Ga, 136Ga, 132Ha, 134Ha, 136Ha, 132Ia, 134Ia, 136Ia, 134Ja, 132Ka, 132La Vibration damping section 133 Second conductive layer 134, 134A, 134B, 134C, 134D, 134E, 134F, 134G, 134H, 134I, 134J Second insulating layer 135 Third conductive layer 136, 136A, 136B, 136C, 136D, 136E, 136F, 136G, 136H, 136I, 136J Third insulating layer 611 Inclined surface 612 Illumination hole 613 Imaging hole 614 Air / water supply hole 615 Treatment tool channel 616 Illumination lens 617 Objective optical system

Claims

1. An ultrasonic probe comprising: a plurality of ultrasonic transducers arranged along the direction of arrangement; a plurality of signal cables electrically connected to each of the ultrasonic transducers; and a substrate electrically connecting the ultrasonic transducers and the signal cables, wherein the substrate has a conductive layer on which a predetermined wiring pattern is formed; and an insulating layer made of an insulating material provided on the side of the conductive layer opposite to the ultrasonic transducers, and the insulating layer has vibration damping sections made of a material with an acoustic impedance different from that of the insulating layer provided between adjacent ultrasonic transducers along the direction of arrangement.

2. The ultrasonic probe according to claim 1, wherein the at least one conductive layer comprises two or more conductive layers, the at least one insulating layer comprises two or more insulating layers, and the substrate is arranged such that the two or more conductive layers and the two or more insulating layers are alternately laminated.

3. The ultrasonic probe according to claim 2, wherein all of the insulating layers are provided with the vibration damping portion.

4. The ultrasonic probe according to claim 2, wherein the vibration damping portion is provided in any of the insulating layers.

5. The ultrasonic probe according to claim 2, wherein the vibration damping portion has a different length in the arrangement direction for each of the insulating layers.

6. The ultrasonic probe according to claim 2, wherein the vibration damping portion has a longer length in the arrangement direction as the insulating layer moves further away from the ultrasonic transducer.

7. The ultrasonic probe according to claim 1, wherein the vibration damping portion is a gap formed on or inside the insulating layer.

8. The ultrasonic probe according to claim 1, wherein the vibration damping portion is formed by adding bubbles or fillers to the surface or inside the insulating layer.

9. The ultrasonic probe according to claim 1, wherein the vibration damping portion is formed by filling the surface or interior of the insulating layer with a material having a different acoustic impedance from the insulating layer.

10. The ultrasonic probe according to claim 1, comprising an insertion portion inserted into a subject, wherein the ultrasonic transducer and the substrate are arranged on the tip side of the insertion portion, and the signal cable extends from the substrate to the base end side of the insertion portion.

11. The ultrasonic probe according to claim 10, comprising an image sensor positioned at the tip of the insertion portion for imaging the inside of the subject.

12. A method for manufacturing an ultrasonic probe, comprising: forming a vibration damping portion on or inside an insulating layer made of an insulating material; forming a conductive layer by forming a predetermined wiring pattern on the insulating layer; laminating a laminate containing a piezoelectric material on the conductive layer; and separating the piezoelectric material into a plurality of ultrasonic transducers arranged along the arrangement direction.

13. The method for manufacturing an ultrasonic probe according to claim 12, wherein the vibration damping portion is located between adjacent ultrasonic transducers along the arrangement direction and is made of a material with a different acoustic impedance from the insulating layer.

14. The method for manufacturing an ultrasonic probe according to claim 12, wherein the vibration damping portion is formed by forming a gap on or inside the insulating layer.

15. The method for manufacturing an ultrasonic probe according to claim 12, wherein the vibration damping portion is formed by adding bubbles or fillers to the surface or inside the insulating layer.

16. The method for manufacturing an ultrasonic probe according to claim 12, wherein a gap is formed on the surface or inside the insulating layer, and the vibration damping portion is formed by filling the gap with a material having a different acoustic impedance from the insulating layer.

17. An ultrasonic probe comprising: a plurality of ultrasonic transducers arranged along the direction of arrangement; a plurality of signal cables electrically connected to each of the ultrasonic transducers; and a substrate electrically connecting the ultrasonic transducers and the signal cables, wherein the substrate has a conductive layer on which a predetermined wiring pattern is formed; and an insulating layer made of an insulating material provided on the side of the conductive layer opposite to the ultrasonic transducers, the insulating layer having vibration damping portions which are gaps formed on the surface or inside the insulating layer between adjacent ultrasonic transducers along the direction of arrangement.

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