US20010042289A1 - Multiple-element acoustic probe comprising a common ground electrode - Google Patents

Multiple-element acoustic probe comprising a common ground electrode Download PDF

Info

Publication number
US20010042289A1
US20010042289A1 US09/117,045 US11704598A US2001042289A1 US 20010042289 A1 US20010042289 A1 US 20010042289A1 US 11704598 A US11704598 A US 11704598A US 2001042289 A1 US2001042289 A1 US 2001042289A1
Authority
US
United States
Prior art keywords
acoustic
aij
transducers
ground electrode
probe according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
US09/117,045
Other versions
US6341408B2 (en
Inventor
Jean-Marc Bureau
Jean-Francois Gelly
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Thales SA
Original Assignee
Thomson CSF SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Thomson CSF SA filed Critical Thomson CSF SA
Assigned to THOMSON-CSF reassignment THOMSON-CSF ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BUREAU, JEAN-MARC, GELLY, JEAN-FRANCOIS
Publication of US20010042289A1 publication Critical patent/US20010042289A1/en
Application granted granted Critical
Publication of US6341408B2 publication Critical patent/US6341408B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
    • B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
    • B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
    • B06B1/02—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy
    • B06B1/06—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction
    • B06B1/0607—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements
    • B06B1/0622—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency making use of electrical energy operating with piezoelectric effect or with electrostriction using multiple elements on one surface
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/42—Piezoelectric device making
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49005—Acoustic transducer

Definitions

  • the field of the invention is that of acoustic transducers that can be used especially in medical or underwater imaging.
  • an acoustic probe comprises a set of piezoelectric transducers connected to an electronic control device by means of an interconnection array.
  • These piezoelectric transducers emit acoustic waves which, after reflection in a given medium, provide information on said medium.
  • one or more acoustic matching plates are attached to the surface of the piezoelectric transducers to improve the transfer of acoustic energy in said medium.
  • These matching plates may be made out of a polymer type material charged with mineral particles whose proportions are adjusted to obtain the desired acoustic properties. In general, these plates are shaped by moulding or machining and then joined by bonding to one of the faces of the piezoelectric transducers.
  • the piezoelectric transducers are separated mechanically by a cutting up of a monolithic plate of piezoelectric material, for example PZT type ceramic. It is then also necessary to cut out the associated acoustic matching layer or layers in the same way so as to avoid any acoustic coupling between elementary transducers through this matching layer or layers. The cutting out of these matching layers and of the piezoelectric layer is therefore generally done simultaneously, for example by means of a diamond-tipped saw.
  • Each elementary piezoelectric transducer must be connected on the one hand to the ground and on the other hand to a positive contact (also called a hot point).
  • the ground is located towards the propagation medium (for example the patient in the case of an acoustic echography probe), namely it should be on the side where the acoustic matching elements are positioned.
  • the propagation medium for example the patient in the case of an acoustic echography probe
  • a conductive layer is deposited and then a plate of piezoelectric material is deposited by bonding.
  • Successive cutting-out operations are performed, in a direction Dy illustrated in FIG. 1, on the matrix of transducers Tij.
  • One or more acoustic matching plates are bonded in the same way.
  • the lower face of the first acoustic matching plate is metallized, enabling the grounds to be brought to the edges of the matrix.
  • the entire unit (acoustic matching plates and piezoelectric material plate) are cut out in the direction Dx perpendicular to the direction Dy.
  • this method has the drawback of mechanically connecting the elementary transducers of one and the same line i in the direction Dx, and is therefore detrimental to the performance characteristics of the acoustic probe that results therefrom.
  • the invention proposes an acoustic probe comprising a continuous ground electrode inserted between elementary piezoelectric transducers uncoupled from one another, and acoustic matching elements also uncoupled from one another so as to resolve the problem of the prior art.
  • an object of the invention is an acoustic probe comprising acoustic matching elements, elementary piezoelectric transducers and an array of interconnections connecting the acoustic transducers to an electronic signal processing and control device characterized in that said probe comprises a continuous ground electrode inserted between the elementary acoustic transducers and acoustic matching elements.
  • the ground electrode may typically be a metal foil, for example made of copper or silver.
  • It may also be a metallized polymer film of the copper-plated or gold-plated polyester or polyimide type, or again a polymer film charged with conductive particles.
  • the acoustic matching elements may advantageously be made of epoxy resin charged with tungsten and/or aluminium oxide particles while the elementary piezoelectric transducers may be made of PZT type ceramic.
  • the acoustic probe comprises acoustic matching elements Aij 1 , with an impedance close to that of the propagation medium of the acoustic probe, that are located above the ground electrode and acoustic matching elements Aij 2 , with an impedance close to that of the piezoelectric transducers, that are located between the ground electrode and the piezoelectric transducers.
  • the piezoelectric transducers being made of ceramic, the elements Aij 1 have an impedance of about 2 to 3 Mega Rayleigh and the elements Aij 2 have an impedance of about 8 to 9 Mega Rayleigh.
  • An object of the invention is also a method for the manufacture of the acoustic probe according to the invention.
  • This method comprises the making of elementary piezoelectric transducers (Tij) on the surface of an array of interconnections connecting the acoustic transducers to an electronic signal processing and control device characterized in that it furthermore comprises the following steps:
  • the selective etching may be done by a CO 2 type laser, an excimer type ultraviolet laser or else a YAG type laser.
  • the ground electrode may be a metallized copper-coated polyimide film, and the acoustic matching elements Aij may then be defined by the etching, with a CO 2 laser at an energy density in the range of some Joules per cm 2 (so as not to corrode the metallization), of a layer of epoxy resin charged with tungsten particles.
  • two layers of acoustic matching material are deposited, a first layer having an impedance close to that of the piezoelectric transducers and a second layer having an impedance close to that of the medium in which the acoustic probe is designed to function.
  • the set of two layers is etched with a corrosion barrier on the conductive layer.
  • a layer that has impedance close to that of the transducers and is conductive is deposited on the surface of a layer of piezoelectric material, the unit is cut out so as to define the piezoelectric transducers Tij and a first series of high-impedance acoustic matching elements.
  • a conductive ground electrode layer is deposited on the set of transducers Tij covered with the elements Aij 1 .
  • a second acoustic matching layer is placed on the surface of the ground electrode P, elements Aij 2 are then defined by the selective cutting out of the low-impedance layer with an etching barrier on the ground electrode.
  • FIG. 1 illustrates an acoustic probe according to the prior art
  • FIG. 2 illustrates a first exemplary acoustic probe according to the invention
  • FIG. 3 illustrates a first step in the manufacture of an exemplary array of interconnections used in an acoustic probe according to the invention
  • FIG. 4 illustrates a second step in the manufacture of an exemplary array of interconnections, used in an acoustic probe according to the invention
  • FIG. 5 illustrates a step in the method of manufacture of an acoustic probe common to the prior art and to the method of the invention
  • FIG. 6 illustrates a step in the method of manufacture of an acoustic probe according to the invention, comprising the depositing of a conductive layer on the surface of the elementary transducers Tij;
  • FIG. 7 illustrates a step in the method of manufacture of an acoustic probe according to the invention, comprising the depositing of acoustic matching plates;
  • FIG. 8 illustrates a step in the method of manufacture of an acoustic probe according to the invention, comprising the selective cutting out of the acoustic matching plates so as to define the elements Aij;
  • FIG. 9 illustrates a second exemplary acoustic probe according to the invention.
  • the acoustic probe according to the invention comprises elementary piezoelectric transducers Tij (organized in a linear matrix or in a way that is preferably two-dimensional), attached to a matrix of facing interconnection pins.
  • This matrix of interconnections is constituted by ends of metal tracks emerging on one of the faces of an array of interconnections, described hereinafter and known as a backing.
  • the opposite ends of the metal tracks are generally connected to an electronic control and analysis device.
  • FIG. 2 illustrates a first exemplary acoustic probe according to the invention in which the entire probe appears to be partially cut.
  • the backing 1 supports the elementary piezoelectric transducers Tij.
  • a continuous ground electrode P is attached to the surface of the transducers Tij and supports the set of the discrete acoustic matching elements Aij that may result from the depositing of one or more layers of acoustic matching material (in the example of FIG. 2, two layers are shown and result in the obtaining of elements Aij 1 and Aij 2 ).
  • the array of interconnections may be made, for example, in the following way:
  • M dielectric substrates are used. On these substrates N conductive tracks are made along an axis Dx. Each substrate may comprise a window that locally leaves the conductive tracks bare. All the M substrates are aligned and stacked in a direction Dy. There is thus obtained a stack of M dielectric substrates, said stack having a cavity comprising M ⁇ N conductive tracks.
  • FIG. 3 illustrates the construction of this stack.
  • the cavity thus formed is filled with a hardening resin that is electrically insulating and possesses the desired properties of acoustic attenuation.
  • the stack is cut along a plane Pc, perpendicular to the axis of the tracks at the level of the preformed cavity as shown in FIG. 4 in order to obtain a surface consisting of M ⁇ N track sections perpendicularly flush with the resin at the level of the backing 1 .
  • FIG. 5 shows the matrix of transducers Tij defined on elementary metallizations Me ij corresponding to the “hot point” contacts referred to here above, the assembly being thus connected electrically to the backing 1 .
  • the unit thus constituted is covered with a conductive ground electrode P as shown in FIG. 6, that is laid on and then bonded, whether it is a metal foil or a film of metallized polymer.
  • the first plate L 1 has high impedance close to that of the material constituting the transducers, the second plate L 2 has lower impedance close to that of the medium in which it is sought to use the acoustic probe.
  • the cutting-out operation must mechanically separate the matching plates without cutting out the ground electrode P.
  • this cutting-out operation can be done by lasers.
  • the laser used may be for example a CO 2 type infrared laser or an excimer type UV laser or a triple or quadruple YAG type laser.
  • the cutting-out operation can be done by means of a laser beam focused and guided so as to describe the cuts required or again by scanning through a mask aligned on the cutting-out paths.
  • the acoustic probe has two series of acoustic matching elements Aij 1 and Aij 2 separated by the continuous ground electrode.
  • This probe comprises elementary transducers Tij attached to a matrix of facing interconnection pins forming part of an interconnection array.
  • FIG. 9 illustrates this configuration.
  • the first series of high-impedance acoustic matching elements may be defined at the same time as the piezoelectric elements through the cutting-out operation, for example by the sawing of the above-mentioned metallization layer Me, the ceramic layer (constituting the elementary transducers) and a first acoustic matching plate L 1 which must be conductive.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Transducers For Ultrasonic Waves (AREA)
  • Ultra Sonic Daignosis Equipment (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)

Abstract

The invention relates to a multiple-element acoustic probe comprising piezoelectric transducers (Tij) and an array of interconnections connecting the acoustic transducers to an electronic signal processing and control device. This probe further comprises a continuous ground electrode (P) integrated between the transducers and acoustic matching elements, facing the piezoelectrical transducers, the acoustic matching elements being totally uncoupled from one another mechanically.

Description

  • The field of the invention is that of acoustic transducers that can be used especially in medical or underwater imaging. [0001]
  • In general, an acoustic probe comprises a set of piezoelectric transducers connected to an electronic control device by means of an interconnection array. [0002]
  • These piezoelectric transducers emit acoustic waves which, after reflection in a given medium, provide information on said medium. Generally, one or more acoustic matching plates, for example of the quarter-wave type, are attached to the surface of the piezoelectric transducers to improve the transfer of acoustic energy in said medium. [0003]
  • These matching plates may be made out of a polymer type material charged with mineral particles whose proportions are adjusted to obtain the desired acoustic properties. In general, these plates are shaped by moulding or machining and then joined by bonding to one of the faces of the piezoelectric transducers. [0004]
  • More specifically, in the case of a probe possessing a set of elementary transducers, the piezoelectric transducers are separated mechanically by a cutting up of a monolithic plate of piezoelectric material, for example PZT type ceramic. It is then also necessary to cut out the associated acoustic matching layer or layers in the same way so as to avoid any acoustic coupling between elementary transducers through this matching layer or layers. The cutting out of these matching layers and of the piezoelectric layer is therefore generally done simultaneously, for example by means of a diamond-tipped saw. [0005]
  • Each elementary piezoelectric transducer must be connected on the one hand to the ground and on the other hand to a positive contact (also called a hot point). [0006]
  • In general, the ground is located towards the propagation medium (for example the patient in the case of an acoustic echography probe), namely it should be on the side where the acoustic matching elements are positioned. [0007]
  • The simultaneous cutting out of acoustic matching layers and of piezoelectric material has the consequence wherein the ground electrode too is cut out when this electrode is constituted by a metal layer inserted between the acoustic matching material and the piezoelectric material. In the case of a one-dimensional array probe the continuity of the ground electrode is preserved in one direction. In the case of a two-dimensional array probe, where the elements are cut out in both directions, the continuity of the ground electrode must be preserved in at least one direction so as to enable the retrieval of the ground at the periphery of the matrix assembly of elementary piezoelectric transducers. [0008]
  • In the prior art, in order to preserve a continuity of the ground in the case of a two-dimensional probe, it has been proposed to proceed as follows: [0009]
  • On the interconnection array [0010] 1, a conductive layer is deposited and then a plate of piezoelectric material is deposited by bonding.
  • Successive cutting-out operations are performed, in a direction Dy illustrated in FIG. 1, on the matrix of transducers Tij. One or more acoustic matching plates are bonded in the same way. The lower face of the first acoustic matching plate is metallized, enabling the grounds to be brought to the edges of the matrix. [0011]
  • Finally, the entire unit (acoustic matching plates and piezoelectric material plate) are cut out in the direction Dx perpendicular to the direction Dy. [0012]
  • There is thus obtained a matrix of elementary piezoelectric transducers Tij covered with acoustic matching elements Ai, with ground electrodes Pi inserted between the transducers Tij and the elements Ai. [0013]
  • However, this method has the drawback of mechanically connecting the elementary transducers of one and the same line i in the direction Dx, and is therefore detrimental to the performance characteristics of the acoustic probe that results therefrom. [0014]
  • This is why the invention proposes an acoustic probe comprising a continuous ground electrode inserted between elementary piezoelectric transducers uncoupled from one another, and acoustic matching elements also uncoupled from one another so as to resolve the problem of the prior art. [0015]
  • More specifically, an object of the invention is an acoustic probe comprising acoustic matching elements, elementary piezoelectric transducers and an array of interconnections connecting the acoustic transducers to an electronic signal processing and control device characterized in that said probe comprises a continuous ground electrode inserted between the elementary acoustic transducers and acoustic matching elements. [0016]
  • The ground electrode may typically be a metal foil, for example made of copper or silver. [0017]
  • It may also be a metallized polymer film of the copper-plated or gold-plated polyester or polyimide type, or again a polymer film charged with conductive particles. [0018]
  • The acoustic matching elements may advantageously be made of epoxy resin charged with tungsten and/or aluminium oxide particles while the elementary piezoelectric transducers may be made of PZT type ceramic. [0019]
  • According to one variant of the invention, the acoustic probe comprises acoustic matching elements Aij[0020] 1, with an impedance close to that of the propagation medium of the acoustic probe, that are located above the ground electrode and acoustic matching elements Aij2, with an impedance close to that of the piezoelectric transducers, that are located between the ground electrode and the piezoelectric transducers.
  • Typically, when the acoustic probe according to the invention is designed to work in an aqueous medium, the piezoelectric transducers being made of ceramic, the elements Aij[0021] 1 have an impedance of about 2 to 3 Mega Rayleigh and the elements Aij2 have an impedance of about 8 to 9 Mega Rayleigh.
  • An object of the invention is also a method for the manufacture of the acoustic probe according to the invention. This method comprises the making of elementary piezoelectric transducers (Tij) on the surface of an array of interconnections connecting the acoustic transducers to an electronic signal processing and control device characterized in that it furthermore comprises the following steps: [0022]
  • the depositing of a conductive layer that constitutes an ground electrode (P) on the surface of the elementary transducers (Tij); [0023]
  • the depositing of at least one layer of acoustic matching material; [0024]
  • the selective etching of the layer or layers of acoustic matching materials with a corrosion barrier on the conductive layer so as to constitute acoustic matching elements (Aij). [0025]
  • Advantageously, the selective etching may be done by a CO[0026] 2 type laser, an excimer type ultraviolet laser or else a YAG type laser.
  • According to one method of manufacture of the acoustic probe of the invention, the ground electrode may be a metallized copper-coated polyimide film, and the acoustic matching elements Aij may then be defined by the etching, with a CO[0027] 2 laser at an energy density in the range of some Joules per cm2 (so as not to corrode the metallization), of a layer of epoxy resin charged with tungsten particles.
  • According to one variant of the method of the invention, two layers of acoustic matching material are deposited, a first layer having an impedance close to that of the piezoelectric transducers and a second layer having an impedance close to that of the medium in which the acoustic probe is designed to function. The set of two layers is etched with a corrosion barrier on the conductive layer. [0028]
  • According to another variant of the invention, a layer that has impedance close to that of the transducers and is conductive is deposited on the surface of a layer of piezoelectric material, the unit is cut out so as to define the piezoelectric transducers Tij and a first series of high-impedance acoustic matching elements. A conductive ground electrode layer is deposited on the set of transducers Tij covered with the elements Aij[0029] 1. A second acoustic matching layer is placed on the surface of the ground electrode P, elements Aij2 are then defined by the selective cutting out of the low-impedance layer with an etching barrier on the ground electrode.
    •
  • The invention will be understood more clearly and other advantages shall appear from the following description, given on an non-restrictive basis and with reference to the appended figures, of which: [0030]
  • FIG. 1 illustrates an acoustic probe according to the prior art; [0031]
  • FIG. 2 illustrates a first exemplary acoustic probe according to the invention; [0032]
  • FIG. 3 illustrates a first step in the manufacture of an exemplary array of interconnections used in an acoustic probe according to the invention; [0033]
  • FIG. 4 illustrates a second step in the manufacture of an exemplary array of interconnections, used in an acoustic probe according to the invention; [0034]
  • FIG. 5 illustrates a step in the method of manufacture of an acoustic probe common to the prior art and to the method of the invention; [0035]
  • FIG. 6 illustrates a step in the method of manufacture of an acoustic probe according to the invention, comprising the depositing of a conductive layer on the surface of the elementary transducers Tij; [0036]
  • FIG. 7 illustrates a step in the method of manufacture of an acoustic probe according to the invention, comprising the depositing of acoustic matching plates; [0037]
  • FIG. 8 illustrates a step in the method of manufacture of an acoustic probe according to the invention, comprising the selective cutting out of the acoustic matching plates so as to define the elements Aij; [0038]
  • FIG. 9 illustrates a second exemplary acoustic probe according to the invention.[0039]
  • The acoustic probe according to the invention comprises elementary piezoelectric transducers Tij (organized in a linear matrix or in a way that is preferably two-dimensional), attached to a matrix of facing interconnection pins. This matrix of interconnections is constituted by ends of metal tracks emerging on one of the faces of an array of interconnections, described hereinafter and known as a backing. The opposite ends of the metal tracks are generally connected to an electronic control and analysis device. [0040]
  • FIG. 2 illustrates a first exemplary acoustic probe according to the invention in which the entire probe appears to be partially cut. The backing [0041] 1 supports the elementary piezoelectric transducers Tij. A continuous ground electrode P is attached to the surface of the transducers Tij and supports the set of the discrete acoustic matching elements Aij that may result from the depositing of one or more layers of acoustic matching material (in the example of FIG. 2, two layers are shown and result in the obtaining of elements Aij1 and Aij2).
  • In the case of a matrix of M×N piezoelectric transducers, the array of interconnections may be made, for example, in the following way: [0042]
  • M dielectric substrates are used. On these substrates N conductive tracks are made along an axis Dx. Each substrate may comprise a window that locally leaves the conductive tracks bare. All the M substrates are aligned and stacked in a direction Dy. There is thus obtained a stack of M dielectric substrates, said stack having a cavity comprising M×N conductive tracks. FIG. 3 illustrates the construction of this stack. [0043]
  • The cavity thus formed is filled with a hardening resin that is electrically insulating and possesses the desired properties of acoustic attenuation. After the hardening of the resin, the stack is cut along a plane Pc, perpendicular to the axis of the tracks at the level of the preformed cavity as shown in FIG. 4 in order to obtain a surface consisting of M×N track sections perpendicularly flush with the resin at the level of the backing [0044] 1.
  • To provide for the connection between these M×N track sections and the piezoelectric transducers Tij, it is possible advantageously to proceed as follows: [0045]
  • The entire surface of the backing [0046] 1 constituted by the M×N track sections is metallized with a layer Me. A layer of PZT ceramic type piezoelectric material is laid thereon. Then, the layer Me and the ceramic is layer are cut out, for example by sawing, so as to define the transducers Tij that are independent of one another. The barrier against the cutting out operation can be made on the surface of the resin and the control of this etching does not require extreme precision. FIG. 5 shows the matrix of transducers Tij defined on elementary metallizations Meij corresponding to the “hot point” contacts referred to here above, the assembly being thus connected electrically to the backing 1.
  • The unit thus constituted is covered with a conductive ground electrode P as shown in FIG. 6, that is laid on and then bonded, whether it is a metal foil or a film of metallized polymer. [0047]
  • Two plates of acoustic matching material L[0048] 1 and L2 are then bonded as shown in FIG. 8. The first plate L1 has high impedance close to that of the material constituting the transducers, the second plate L2 has lower impedance close to that of the medium in which it is sought to use the acoustic probe. The cutting-out operation must mechanically separate the matching plates without cutting out the ground electrode P.
  • In this way, an acoustic decoupling of the elementary transducers Tij is obtained, at the same time as electrical continuity is kept making it possible to recover the ground contact at the periphery of the probe. [0049]
  • In particular, this cutting-out operation can be done by lasers. The laser used may be for example a CO[0050] 2 type infrared laser or an excimer type UV laser or a triple or quadruple YAG type laser.
  • By an appropriate choice of the different constituent elements of the ground electrodes and the acoustic matching elements, and of the parameters of the laser beam, namely wavelength and energy density, it becomes possible to carry out a selective machining of the acoustic matching plates without affecting the ground electrode. The cutting-out operation can be done by means of a laser beam focused and guided so as to describe the cuts required or again by scanning through a mask aligned on the cutting-out paths. [0051]
  • According to another variant of the invention, the acoustic probe has two series of acoustic matching elements Aij[0052] 1 and Aij2 separated by the continuous ground electrode.
  • This probe comprises elementary transducers Tij attached to a matrix of facing interconnection pins forming part of an interconnection array. FIG. 9 illustrates this configuration. The first series of high-impedance acoustic matching elements may be defined at the same time as the piezoelectric elements through the cutting-out operation, for example by the sawing of the above-mentioned metallization layer Me, the ceramic layer (constituting the elementary transducers) and a first acoustic matching plate L[0053] 1 which must be conductive.
  • The unit thus constituted, formed by the electrodes Me[0054] ij, the transducers Tij, the elements Aij1, is covered with a conductive ground electrode P that is laid on and then bonded.
  • It is then possible to bond a second low-impedance plate L[0055] 2 cut out by etching, with an etching barrier, on the ground electrode so as to define the low-impedance elements Aij2. One of the useful aspects of this variant of the invention lies in the fact that the thickness to be cut out by selective etching is small and, at the same time, a probe is available that advantageously has high-impedance elements and low-impedance elements.

Claims (13)

What is claimed is:
1. An acoustic probe comprising acoustic matching elements (Aij), elementary piezoelectric transducers (Tij) and an array of interconnections connecting the acoustic transducers to an electronic signal processing and control device characterized in that said probe comprises a continuous ground electrode (P) inserted between the elementary acoustic transducers (Tij) and acoustic matching elements (Aij).
2. An acoustic probe according to
claim 1
, characterized in that the ground electrode is a copper or silver type of metal foil.
3. An acoustic probe according to
claim 1
, characterized in that the ground electrode is a metallized polymer film of the copper-coated or gold-coated polyimide or polyester type.
4. An acoustic probe according to
claim 1
, characterized in that the ground electrode is a polymer film charged with conductive particles.
5. An acoustic probe according to one of the
claims 1
 to
4
, characterized in that the acoustic matching elements are advantageously made of epoxy resin charged with particles of tungsten and/or aluminium oxide.
6. An acoustic probe according to one of the
claims 1
 to
4
, characterized in that the elementary piezoelectric transducers (Tij) are made of PZT type ceramic.
7. An acoustic probe according to one of the
claims 1
 to
6
, characterized in that it comprises acoustic matching elements (Aij1), having an impedance close to that of the transducers (Tij) and being located on the surface of the ground electrode (P) and acoustic matching elements (Aij2), having an impedance close to that of the propagation medium of the probe and being located on the surface of the elements (Aij1).
8. An acoustic probe according to one of the
claims 1
 to
6
, characterized in that it comprises acoustic matching elements (Aij1) located between the piezoelectric transducers and the ground electrode (P) and elements (Aij2), having an impedance close to that of the propagation medium of the probe and being located on the surface of the ground electrode (P).
9. A method for the manufacture of the acoustic probe according to one of the
claims 1
 to
8
, comprising the making of elementary piezoelectric transducers (Tij) on the surface of an array of interconnections connecting the acoustic transducers to an electronic signal processing and control device characterized in that said method furthermore comprises the following steps:
the depositing of a conductive layer that constitutes an ground electrode (P) on the surface of the elementary transducers (Tij);
the depositing of at least one layer of acoustic matching material, on the conductive surface;
the selective etching of the layer or layers of acoustic matching materials, with a corrosion barrier on the conductive layer, so as to constitute acoustic matching elements (Aij, Aij1, Aij2).
10. A method for the manufacture of an acoustic probe according to
claim 9
, characterized in that the selective etching is done by laser.
11. A method for the manufacture of an acoustic probe according to
claim 10
, characterized in that the acoustic matching material is an epoxy resin charged with particles of tungsten and/or aluminium oxide, the ground electrode is a copper-metallized polyimide film, the laser being a CO2 laser emitting in the infrared.
12. A method for the manufacture of an acoustic probe according to
claim 10
, characterized in that the energy density of the laser beam is some Joules per cm2.
13. A method for the manufacture of an acoustic probe according to one of the
claims 9
 to
12
, characterized in that it comprises the depositing of two layers of acoustic matching materials with different values of impedance so as to define elements (Aij1) with impedance close to that of the piezoelectric transducers (Tij) and elements (Aij2) with impedance close to that of the propagation medium of the probe.
US09/117,045 1996-11-26 1997-11-21 Method of manufacturing a multiple-element acoustic probe comprising a common ground electrode Expired - Lifetime US6341408B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9614472 1996-11-26
FR9614472A FR2756447B1 (en) 1996-11-26 1996-11-26 MULTIPLE ELEMENT ACOUSTIC PROBE COMPRISING A COMMON MASS ELECTRODE
PCT/FR1997/002110 WO1998023392A1 (en) 1996-11-26 1997-11-21 Sound probe with multiple elements comprising a common earth electrode

Publications (2)

Publication Number Publication Date
US20010042289A1 true US20010042289A1 (en) 2001-11-22
US6341408B2 US6341408B2 (en) 2002-01-29

Family

ID=9498040

Family Applications (1)

Application Number Title Priority Date Filing Date
US09/117,045 Expired - Lifetime US6341408B2 (en) 1996-11-26 1997-11-21 Method of manufacturing a multiple-element acoustic probe comprising a common ground electrode

Country Status (10)

Country Link
US (1) US6341408B2 (en)
EP (1) EP0883447B1 (en)
JP (1) JP2000504274A (en)
KR (1) KR100508222B1 (en)
CN (1) CN1105039C (en)
DE (1) DE69710314T2 (en)
DK (1) DK0883447T3 (en)
FR (1) FR2756447B1 (en)
NO (1) NO983363L (en)
WO (1) WO1998023392A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080074945A1 (en) * 2004-09-22 2008-03-27 Miyuki Murakami Agitation Vessel
KR101482474B1 (en) 2011-01-28 2015-01-21 가부시끼가이샤 도시바 Ultrasonic transducer, ultrasonic probe, and method for producing ultrasonic transducer
US20160199031A1 (en) * 2015-01-12 2016-07-14 Samsung Medison Co., Ltd. Matching member and ultrasound probe including the same
CN109985796A (en) * 2019-03-25 2019-07-09 中国船舶重工集团公司第七一五研究所 A kind of polygon array element piezo-electricity composite material energy converter preparation method

Families Citing this family (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2770932B1 (en) 1997-11-07 2001-11-16 Thomson Csf METHOD FOR MANUFACTURING AN ACOUSTIC PROBE
FR2779575B1 (en) * 1998-06-05 2003-05-30 Thomson Csf MULTI-PIECE ACOUSTIC PROBE COMPRISING A CONDUCTIVE COMPOSITE FILM AND MANUFACTURING METHOD
FR2802449B1 (en) * 1999-12-17 2002-03-01 Thomson Csf MULTI-ELEMENT LINEAR ACOUSTIC PROBE AND METHOD FOR THE COLLECTIVE MANUFACTURE OF ACOUSTIC PROBES
EP1177623B1 (en) * 2000-02-22 2009-08-05 Nxp B.V. Method of manufacturing a piezoeletric filter with an acoustic resonator situated on an acoustic reflector layer formed on a carrier substrate
FR2806332B1 (en) * 2000-03-14 2002-06-14 Thomson Csf UNIDIRECTIONAL ACOUSTIC SENSOR AND MANUFACTURING METHOD
FR2810907B1 (en) * 2000-06-30 2002-10-31 Thomson Csf METHOD FOR MANUFACTURING A MULTI-PIECE ACOUSTIC PROBE USING A NEW METHOD FOR PRODUCING ELECTRICAL MASS
FR2815723B1 (en) * 2000-10-24 2004-04-30 Thomson Csf SYSTEM METHOD AND PROBE FOR OBTAINING IMAGES VIA A BROADCAST EMITTED BY AN ANTENNA AFTER REFLECTION OF THESE WAVES AT A TARGET ASSEMBLY
FR2818170B1 (en) * 2000-12-19 2003-03-07 Thomson Csf METHOD OF MANUFACTURING A MULTI-ELEMENT ACOUSTIC PROBE USING A METALLIC AND ABLATE POLYMER FILM AS A GROUND PLAN
US6759791B2 (en) * 2000-12-21 2004-07-06 Ram Hatangadi Multidimensional array and fabrication thereof
US6864620B2 (en) * 2000-12-22 2005-03-08 Ngk Insulators, Ltd. Matrix type actuator
JP3883823B2 (en) * 2001-06-19 2007-02-21 日本電波工業株式会社 Matrix-type ultrasonic probe and manufacturing method thereof
US6859984B2 (en) * 2002-09-05 2005-03-01 Vermon Method for providing a matrix array ultrasonic transducer with an integrated interconnection means
US20040220531A1 (en) * 2003-05-01 2004-11-04 Bui Tuan S. System and method operating microreservoirs delivering medication in coordination with a pump delivering diluent
JP4503347B2 (en) * 2004-04-28 2010-07-14 日本電波工業株式会社 Manufacturing method of ultrasonic probe
JP4513596B2 (en) * 2004-08-25 2010-07-28 株式会社デンソー Ultrasonic sensor
JP4693386B2 (en) * 2004-10-05 2011-06-01 株式会社東芝 Ultrasonic probe
FR2889403B1 (en) * 2005-07-29 2007-11-09 Thales Sa PROCESS FOR PRODUCING AN ACOUTICAL TRANSDUCER
US20070046149A1 (en) * 2005-08-23 2007-03-01 Zipparo Michael J Ultrasound probe transducer assembly and production method
US7622848B2 (en) * 2006-01-06 2009-11-24 General Electric Company Transducer assembly with z-axis interconnect
JP5002402B2 (en) * 2007-10-03 2012-08-15 株式会社東芝 Ultrasonic probe and ultrasonic diagnostic apparatus
DE102008055116A1 (en) * 2008-12-23 2010-07-01 Robert Bosch Gmbh Method for producing an ultrasonic transducer
US9530955B2 (en) 2011-11-18 2016-12-27 Acist Medical Systems, Inc. Ultrasound transducer and processing methods thereof
KR101387187B1 (en) * 2012-02-24 2014-04-21 경북대학교 산학협력단 Method of Manufacture for Multi-dimensional Transducer
US9536511B2 (en) * 2013-12-31 2017-01-03 Acist Medical Systems, Inc. Ultrasound transducer stack
CN105596027B (en) * 2014-11-05 2018-07-17 香港理工大学深圳研究院 Two dimensional array ultrasound energy converter based on 3-D supersonic imaging and preparation method thereof
WO2017199861A1 (en) * 2016-05-20 2017-11-23 オリンパス株式会社 Ultrasonic transducer module, ultrasonic endoscope, and method for manufacturing ultrasonic transducer module
CN106124618B (en) * 2016-06-21 2018-10-02 济南大学 A kind of sonac for cement concrete hydration reaction monitoring the process
KR101830205B1 (en) * 2017-02-17 2018-02-21 주식회사 베프스 Piezoelectric sensor manufacturing method and piezoelectric sensor using the same
US10710116B2 (en) * 2017-09-21 2020-07-14 General Electric Company Methods and systems for manufacturing an ultrasound probe
US11883846B2 (en) * 2019-06-14 2024-01-30 GE Precision Healthcare LLC Method for manufacturing an ultrasound transducer and ultrasound probe

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57147397A (en) * 1981-03-09 1982-09-11 Hitachi Medical Corp Ultrasonic probe
DE3678635D1 (en) * 1985-05-20 1991-05-16 Matsushita Electric Ind Co Ltd ULTRASONIC CONVERTER.
US5274296A (en) * 1988-01-13 1993-12-28 Kabushiki Kaisha Toshiba Ultrasonic probe device
US5050588A (en) * 1990-02-08 1991-09-24 Richard Grey High energy ultrasonic lens assembly with mounting facets
US5423220A (en) * 1993-01-29 1995-06-13 Parallel Design Ultrasonic transducer array and manufacturing method thereof
US5553035A (en) * 1993-06-15 1996-09-03 Hewlett-Packard Company Method of forming integral transducer and impedance matching layers
CA2139151A1 (en) * 1994-01-14 1995-07-15 Amin M. Hanafy Two-dimensional acoustic array and method for the manufacture thereof
FR2740933B1 (en) * 1995-11-03 1997-11-28 Thomson Csf ACOUSTIC PROBE AND METHOD FOR PRODUCING THE SAME
GB9525418D0 (en) * 1995-12-13 1996-07-17 Marconi Gec Ltd Acoustic imaging arrays
US5732706A (en) * 1996-03-22 1998-03-31 Lockheed Martin Ir Imaging Systems, Inc. Ultrasonic array with attenuating electrical interconnects

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080074945A1 (en) * 2004-09-22 2008-03-27 Miyuki Murakami Agitation Vessel
US8235578B2 (en) * 2004-09-22 2012-08-07 Beckman Coulter, Inc. Agitation vessel
KR101482474B1 (en) 2011-01-28 2015-01-21 가부시끼가이샤 도시바 Ultrasonic transducer, ultrasonic probe, and method for producing ultrasonic transducer
US20160199031A1 (en) * 2015-01-12 2016-07-14 Samsung Medison Co., Ltd. Matching member and ultrasound probe including the same
CN109985796A (en) * 2019-03-25 2019-07-09 中国船舶重工集团公司第七一五研究所 A kind of polygon array element piezo-electricity composite material energy converter preparation method

Also Published As

Publication number Publication date
FR2756447A1 (en) 1998-05-29
EP0883447A1 (en) 1998-12-16
CN1209778A (en) 1999-03-03
DE69710314D1 (en) 2002-03-21
CN1105039C (en) 2003-04-09
KR19990081844A (en) 1999-11-15
DK0883447T3 (en) 2002-05-27
FR2756447B1 (en) 1999-02-05
US6341408B2 (en) 2002-01-29
NO983363D0 (en) 1998-07-21
KR100508222B1 (en) 2006-06-21
WO1998023392A1 (en) 1998-06-04
EP0883447B1 (en) 2002-02-06
DE69710314T2 (en) 2003-01-23
NO983363L (en) 1998-09-03
JP2000504274A (en) 2000-04-11

Similar Documents

Publication Publication Date Title
US6341408B2 (en) Method of manufacturing a multiple-element acoustic probe comprising a common ground electrode
US20240315137A1 (en) Methods for Manufacturing Ultrasound Transducers and Other Components
EP3121844B1 (en) Ultrasound transducers
US11845108B2 (en) Methods for manufacturing ultrasound transducers and other components
US6449821B1 (en) Method of constructing segmented connections for multiple elevation transducers
US5722137A (en) Method for making a high density interconnect for an ultrasonic phased array
US5091893A (en) Ultrasonic array with a high density of electrical connections
US6859984B2 (en) Method for providing a matrix array ultrasonic transducer with an integrated interconnection means
JP3766978B2 (en) Acoustic probe manufacturing method
EP0681513A1 (en) Manufacturing method of an mechanically focusing ultrasonic transducer array
JP2004511290A (en) Intravascular ultrasound catheter placement
US6522051B1 (en) Multielement sound probe comprising a composite electrically conducting coating and method for making same
JP2001509901A (en) Method of manufacturing acoustic probe
CA2243291A1 (en) Sound probe with multiple elements comprising a common earth electrode

Legal Events

Date Code Title Description
AS Assignment

Owner name: THOMSON-CSF, FRANCE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:BUREAU, JEAN-MARC;GELLY, JEAN-FRANCOIS;REEL/FRAME:009619/0499

Effective date: 19980622

STCF Information on status: patent grant

Free format text: PATENTED CASE

FPAY Fee payment

Year of fee payment: 4

FPAY Fee payment

Year of fee payment: 8

FPAY Fee payment

Year of fee payment: 12