Method for producing intravascular ultrasonic transducers and structure thereof

Patent metadata

Field	Value
Publication number	US-2016351783-A1
Application number	US-201515114712-A
Country	US
Kind code	A1
Filing date	Jan 28, 2015
Priority date	Jan 29, 2014
Publication date	Dec 1, 2016
Grant date	—

Abstract

The present invention relates to a method for producing an intravascular ultrasonic transducer and a structure for same, the method for producing a ultrasonic transducer producing a single element by: forming a piezoelectric element lapped according to a previously set thickness; depositing conductive material on the lapped surface of the piezoelectric element; forming a matched layer and a rear surface layer by casting the front and rear surfaces of the piezoelectric element to which conductive material has been deposited; lapping according to a previously set thickness; and dicing the bulk material, which is a stack of a matched layer, a piezoelectric element and a rear surface layer, along the stack direction so that the size of the element is less than the critical size for intravascular ultrasound (IVUS).

First claim

1 . A method for producing an ultrasonic transducer, comprising:
forming a piezoelectric material lapped according to a preset thickness; depositing a conductive material on a lapped surface of the piezoelectric material; casting a front surface and a rear surface of the piezoelectric material having the deposited conductive material to respectively form a matching layer and a backing layer and lapping according to a preset thickness; and dicing the bulk material with a stack of the matching layer, the piezoelectric material and the backing layer along a stack direction to produce single elements which are less than or equal to a threshold size for intravascular ultrasound (IVUS).

2 . The method for producing an ultrasonic transducer according to claim 1 , wherein the matching layer and the backing layer are formed directly on the conductive material through the casting without using an adhesive material.

3 . The method for producing an ultrasonic transducer according to claim 1 , wherein the matching layer and the backing layer are cured using a centrifugal separator after the casting.

4 . The method for producing an ultrasonic transducer according to claim 1 , wherein the conductive material is chrome or gold.

5 . An ultrasonic transducer structure comprising:
a tube for insertion into a blood vessel for IVUS; an ultrasonic transducer of a single element consisting of a stack of a matching layer, a piezoelectric material and a backing layer, and installed at an end of the tube to obtain an ultrasonic image; and a support positioned between one side wall of the tube and the ultrasonic transducer to form an angle at which the ultrasonic transducer is oriented, and to adjust the angle to make an ultrasonic radiation angle of the ultrasonic transducer different from an insertion angle of the tube.

6 . The ultrasonic transducer structure according to claim 5 , wherein the angle at which the ultrasonic transducer is oriented by the support is determined to range between 0° and 90° from an insertion direction of the tube, to simultaneously obtain ultrasonic images of the insertion direction of the tube and a wall surface of the blood vessel into which the tube is inserted, or to estimate a Doppler frequency and calculate a blood flow velocity.

7 . The ultrasonic transducer structure according to claim 5 , wherein the ultrasonic transducer is formed in rectangular shape,
a length of a short side of the ultrasonic transducer is at least less than or equal to a diameter of the tube, and a length of a long side of the ultrasonic transducer is larger than or equal to the diameter of the tube, and the long side of the ultrasonic transducer is inserted along an inner wall surface of the tube.

8 . The ultrasonic transducer structure according to claim 5 , wherein the end of the tube at which the ultrasonic transducer is installed has a cutting surface formed at a slant in consideration of the ultrasonic radiation direction of the ultrasonic transducer.

9 . The ultrasonic transducer structure according to claim 5 , wherein the ultrasonic transducer forms a gradient such that a center surface is concave, to converge a beam to a geometrical focus of the ultrasonic transducer.

10 . The ultrasonic transducer structure according to claim 5 , wherein the ultrasonic transducer further comprises a convex lens attached to a front surface, to converge a beam to a geometrical focus of the ultrasonic transducer.

11 . The ultrasonic transducer structure according to claim 5 , wherein the ultrasonic transducer further comprises an optical source module which is inserted into a certain region of the ultrasonic transducer to emit an optical signal for photoacoustic imaging or optical coherence tomography (OCT) imaging.

12 . The ultrasonic transducer structure according to claim 5 , wherein an electrical signal is supplied to the backing layer, and
ground is created by connecting a housing to the matching layer.

13 . The ultrasonic transducer structure according to claim 5 , wherein the ultrasonic transducer is produced as a single element by forming a piezoelectric material lapped according to a preset thickness,
depositing a conductive material on a lapped surface of the piezoelectric material, casting a front surface and a rear surface of the piezoelectric material having the deposited conductive material to respectively form a matching layer and a backing layer and lapping according to a preset thickness, and dicing the bulk material consisting of a stack of the matching layer, the piezoelectric material and the backing layer along a stack direction to allow insertion into the tube.

14 . The ultrasonic transducer structure according to claim 5 , wherein the ultrasonic transducer of a single element consists of a sequential stack of the piezoelectric material, a first signal pad, a ground pad formed spaced apart from the first signal pad, a flexible printed circuit board (FPCB), and a second signal pad electrically connected to the first signal pad through a via penetrating the FPCB,
the backing layer is lapped according to a preset thickness and is formed on a lower surface of the second signal pad, and after the matching layer electrically connects an upper surface of the piezoelectric material and the ground pad, the matching layer is lapped according to a preset thickness and is formed on the upper surface of the piezoelectric material.

15 . The ultrasonic transducer structure according to claim 14 , wherein a conductive material is deposited on an upper surface of the FPCB to connect the piezoelectric material to the ground pad.

16 . The ultrasonic transducer structure according to claim 14 , wherein the FPCB is polyimide.

17 . The ultrasonic transducer structure according to claim 14 , wherein the ultrasonic transducer is formed in rectangular shape,
a length of a short side of the ultrasonic transducer is at least less than or equal to a diameter of the tube, and a length of a long side of the ultrasonic transducer is larger than or equal to the diameter of the tube, and the long side of the ultrasonic transducer is inserted along an inner wall surface of the tube.

18 . The ultrasonic transducer structure according to claim 14 , wherein the ultrasonic transducer forms a gradient such that a center surface is concave, to converge a beam to a geometrical focus of the ultrasonic transducer.

19 . The ultrasonic transducer structure according to claim 14 , wherein the ultrasonic transducer further comprises an optical source module which is inserted into a certain region of the ultrasonic transducer to emit an optical signal for photoacoustic imaging or optical coherence tomography (OCT) imaging.

Assignees

• Univ Sogang Res Foundation

Inventors

• Chang Jin Ho
• Song Tai-Kyong
• Yoo Yang Mo
• Lee Junsu

Classifications

• H01L41/083 Primary

  Electricity · mapped topic

• H01L41/27

  Electricity · mapped topic

• H01L41/35

  Electricity · mapped topic

• A61B8/12 Primary

  in body cavities or body tracts, e.g. by using catheters · CPC title

• A61B8/0891

  for diagnosis of blood vessels · CPC title