JP2005012426A - Ultrasonic probe and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic probe in which a material cost is inexpensive and a production yield is high, and to provide a manufacturing method thereof. <P>SOLUTION: The ultrasonic probe is provided with a plurality of piezoelectric vibrators 1 each having an upper electrode 7 formed on one surface side and a lower electrode 9 formed on the other surface side, and being disposed in parallel with a regular interval; a first flexible printed board 8 electrically connected to the upper electrodes 7 of these piezoelectric vibrator 1; a second flexible printed board 10 in which a plurality of electrodes 11 each having acutely formed one end are disposed in parallel with a predetermined interval, and the other end of the electrode portions 11 are electrically connected at a proportion of one to the lower electrodes 9 of at least two or more piezoelectric vibrators 1; and a third flexible printed board 12 having lead electrodes 15 being each electrically connected to one end side of the plurality of electrode portions 11 via a conductive paste 16. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ultrasonic probe used for ultrasonic diagnosis and a method for manufacturing the same, for example.
[0002]
[Prior art]
As this type of ultrasonic probe, one shown in FIG. 3 is known.
[0003]
The ultrasonic probe includes a plurality of piezoelectric vibrators 22 arranged in parallel at a predetermined interval, and two layers of backing materials 23 and 24 are bonded to the lower surface of the piezoelectric vibrator 22. Has been. Further, acoustic matching layers 25 and 26 are bonded in layers on the upper surface portions of the piezoelectric vibrators 22, and an acoustic lens 27 is attached to the upper surface portion of the acoustic matching layer 26.
[0004]
A ground electrode 28 is provided on the back side of the piezoelectric vibrator 22, and a copper plate 29 serving as a ground line is soldered to the ground electrode 28. A signal electrode 30 is provided on the front side of the piezoelectric vibrator 22, and a lead wire 32 of a flexible printed circuit board (hereinafter referred to as FPC) 31 manufactured individually according to the product size is soldered to the signal electrode 30. ing.
[0005]
Electrodes 33 and 34 are provided on the upper and lower surfaces of the piezoelectric vibrator 22 as shown in FIG. The ground electrode 28 and the signal electrode 30 are drawn from the electrodes 33 and 34 and are formed of gold or silver (see, for example, Patent Document 1).
[0006]
[Patent Document 1]
JP-A-8-307996 Publication
[Problems to be solved by the invention]
However, conventionally, hundreds of vibrators 22 are arranged with an arrangement pitch of about 0.1 mm, and one lead wire 32 must be soldered to each of the vibrators 22. There was an inconvenience of lowering.
[0008]
In addition, the FPC 31 for signal lines must be prepared separately depending on the size and the number of arrays of ultrasonic probes, and there is a problem that the price of the FPC 31 is increased.
[0009]
Furthermore, since the height dimension of the vibrator 22 is as low as about 0.2 to 0.4 mm, it is difficult to form the ground electrode 28 and the signal electrode 30 so as not to short-circuit the electrodes 33 and 34 on the upper and lower surfaces, and the yield. It was a factor to lower.
[0010]
Further, the soldering of the lead wire 32 and the signal electrode 30 requires a flux application step and a step of applying and curing a protective resin for the soldered portion, which increases the number of manufacturing steps.
[0011]
In addition, it is difficult to cope with lead-free solder, which is required for electrical equipment recently.
[0012]
The present invention has been made paying attention to the above circumstances, and an object of the present invention is to provide an ultrasonic probe and a method for manufacturing the ultrasonic probe that can reduce the material cost and increase the manufacturing yield.
[0013]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the first aspect of the present invention has a ground electrode formed on one surface side and a signal electrode formed on the other surface side, and is arranged in parallel at a predetermined interval. A plurality of piezoelectric vibrators, a first flexible printed circuit board electrically connected to the ground electrodes of the piezoelectric vibrators, and a plurality of electrode portions formed so that one end side thereof is substantially sharp with a predetermined interval. A second flexible printed circuit board arranged in parallel and electrically connected to the signal electrodes of at least two piezoelectric vibrators of the plurality of piezoelectric vibrators at a ratio of one to the other end side of the electrode portions; And a third flexible printed circuit board having a lead electrode electrically connected to each of the plurality of electrode portions through a conductive member.
[0014]
According to a third aspect of the present invention, a plurality of piezoelectric vibrators each having a ground electrode formed on one surface side and a signal electrode formed on the other surface side and arranged in parallel with a predetermined interval A step of electrically connecting the first flexible printed circuit board to the ground electrode and a plurality of electrode portions each having one end side formed substantially sharply arranged in parallel at a predetermined interval. Electrically connecting the other end side of the electrode part of the flexible printed circuit board to the signal electrodes of at least two piezoelectric vibrators of the plurality of piezoelectric vibrators at a ratio of one, and the plurality of electrode parts Electrically connecting the lead electrode of the third flexible printed circuit board to the one end side of each through a conductive member.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the embodiment shown in FIGS. FIG. 1 is an enlarged perspective view showing a part of an ultrasonic probe according to an embodiment of the present invention.
[0016]
The ultrasonic probe includes a plurality of piezoelectric vibrators 1 arranged in parallel at a predetermined interval, and two acoustic matching layers 2 and 3 are formed on the upper surface of the piezoelectric vibrator 1. An acoustic lens 4 is provided. First and second backing materials 5 and 6 are bonded in layers to the lower surface of the piezoelectric vibrator 1.
[0017]
Adhesion between the piezoelectric vibrator 1 and the first backing material 5 and adhesion between the first and second backing materials 5 and 6 are each performed with a thermosetting epoxy adhesive.
[0018]
The piezoelectric vibrators 1 are arranged at a pitch of 0.1 mm, the width dimension is 0.07 mm, and the interval is 0.03 mm.
[0019]
On the upper and lower surface portions of the piezoelectric vibrator 1, upper and lower electrodes 7 and 9 are formed of a thick silver film. The upper surface electrode 7 is a ground electrode, and a first flexible printed circuit board (hereinafter referred to as a first FPC) 8 is electrically connected to the upper surface electrode 7 by a conductive paste. The electrode 19 of the first FPC 8 is formed by covering the entire surface of one of the insulating members made of a tape-like polyimide resin with a copper foil having a thickness of 18 μm. The surface of the copper foil is further thickened. Gold plating with a thickness of 0.05 μm is applied. This gold plating is for preventing oxidation of the copper foil and obtaining reliable conduction.
[0020]
The lower surface electrode 9 of the piezoelectric vibrator 1 is a signal electrode, and one end side of a second flexible printed circuit board (hereinafter referred to as second FPC) 10 is electrically connected to the lower surface electrode 9 through a conductive paste. Has been.
[0021]
On the one end side of the second FPC 10, a plurality of electrode portions 11 are arranged in parallel at a predetermined interval. The plurality of electrode portions 11 are composed of copper foil and gold plating applied to the surface of the copper foil. Each of the plurality of electrode parts 11 is formed so that one end side is substantially sharp, and the other end side is connected to the lower surface electrodes 9 of the three piezoelectric vibrators 1.
[0022]
A plurality of third flexible printed circuit boards (hereinafter referred to as third FPCs) 12 and 13 are bonded to the other end portion side of the second FPC 10 by a non-conductive epoxy adhesive 14. Two lead electrodes 15 as lead lines are formed on each of the third FPCs 12 and 13. Each lead electrode 15 is electrically connected to the substantially sharp one end side of the electrode portion 11 of the second FPC 10 via a conductive paste 16 as a conductive member.
[0023]
Backing materials 5 and 6 are bonded to the lower surface of the piezoelectric vibrator 1 via an epoxy adhesive 21.
[0024]
Next, a method for manufacturing the above-described ultrasonic probe will be described with reference to FIG.
[0025]
First, as shown in FIG. 2A, a piezoelectric vibrator substrate 17 is prepared in which electrodes 7 and 9 made of thick silver films are formed on the entire upper and lower surface portions.
[0026]
Next, a silver paste 18 is applied on the electrodes 7 and 9 of the base material 17, and as shown in FIG. 2B, the electrode 7 has one end side of the first FPC 8 and the electrode 9 has the second FPC 10. One end side is connected respectively.
[0027]
The ground of each vibrator 1 may be common, and there is one electrode 19 of the first FPC 8.
[0028]
A plurality of electrode portions 11 are continuously formed on one end side of the second FPC 10. One end sides of the plurality of electrode portions 11 are formed to be substantially sharp, and the pitch between the one end portions is 0.3 mm.
[0029]
Next, as shown in FIG. 2C, a plurality of third FPCs 12 and 13 are bonded to the other end of the second FPC 10 by a non-conductive adhesive 14.
[0030]
Then, as shown in FIG. 2D, a conductive paste 16 is applied by dispensing between the substantially sharp one end side of the electrode 11 of the second FPC 10 and the electrodes 15 of the third FPCs 12 and 13. Heat cure. The curing conditions are a temperature of 150 ° C. and a heating time of 3 minutes.
[0031]
Thereafter, as shown in FIG. 2 (e), the backing materials 5 and 6 are bonded to the lower surface portion of the piezoelectric vibrator substrate 17 by the epoxy adhesive 21.
[0032]
After this bonding, as shown in FIG. 2 (f), the first FPC 8 and the second FPC 10 are bent at a right angle, and after this bending, the piezoelectric vibrator substrate 17 and the first FPC 8, and The electrode 11 of the second FPC 10 and the backing material 5 are divided at a pitch of 0.1 mm. By this step, a plurality of piezoelectric vibrators 1 are formed, and a plurality of continuous electrodes 11 are divided into one by one.
[0033]
With this division, one lead electrode 15 is electrically connected to three piezoelectric vibrators 1 through one electrode 11.
[0034]
Finally, as shown in FIG. 2G, the acoustic matching layers 2 and 3 and the lens layer 4 are formed on the upper surface of the divided piezoelectric vibrator 1 to complete.
[0035]
As described above, since one lead electrode 15 is connected to a plurality (three) of the piezoelectric vibrators 1 via one electrode 11, the lead electrode 15 and the vibrator 1 are aligned with high accuracy. In addition, a fine connection process is unnecessary, and the manufacturing yield can be increased.
[0036]
Further, the lead line FPCs 12 and 13 can be made common to ultrasonic probes of various specifications, and the cost can be reduced.
[0037]
In the above-described embodiment, the acoustic matching layers 2 and 3 are formed after the transducer base material 17 is divided, but may be formed before the transducer base material 17 is divided.
[0038]
In addition, the plurality of electrodes 11 of the second FPC 10 are configured to be continuous in a mountain shape, but are not limited thereto, and may have other shapes.
[0039]
Furthermore, the conductive paste is applied between the second FPC 10 and the third FPCs 12 and 13 by dispensing, but may be supplied by, for example, an ink jet method.
[0040]
Of course, the present invention can be variously modified within the scope of the gist thereof.
[0041]
【The invention's effect】
As described above, according to the present invention, the third flexible printed circuit board for the lead line can be used in common for the ultrasonic probes of various specifications, and the cost can be reduced.
[0042]
In addition, high-precision alignment between the lead line and the vibrator and a fine connection process are unnecessary, and the manufacturing yield can be increased.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an ultrasonic probe according to an embodiment of the present invention.
FIG. 2 is a view showing a manufacturing process of the ultrasonic probe.
FIG. 3 is a perspective view showing a conventional ultrasonic probe.
FIG. 4 is a diagram showing an electrode arrangement configuration of a conventional piezoelectric vibrator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Piezoelectric vibrator, 5, 6 ... Backing material, 7 ... Upper surface electrode (earth electrode), 8 ... 1st flexible printed circuit board, 9 ... Lower surface electrode (signal electrode), 10 ... 2nd flexible printed circuit board, 11 DESCRIPTION OF SYMBOLS ... Electrode part, 12 ... 3rd flexible substrate, 14 ... Epoxy adhesive agent (nonelectroconductive adhesive), 15 ... Lead electrode, 16 ... Conductive paste (conductive member), 17 ... Vibrator base material.

Claims (3)

A plurality of piezoelectric vibrators each having a ground electrode formed on one surface side and a signal electrode formed on the other surface side, and arranged in parallel at a predetermined interval;
A first flexible printed circuit board electrically connected to the ground electrode of these piezoelectric vibrators;
A plurality of electrode portions having one end side formed in a substantially sharp shape are arranged in parallel at a predetermined interval, and the other end side of the electrode portion is provided with at least two piezoelectric vibrators of the plurality of piezoelectric vibrators. A second flexible printed circuit board that is electrically connected to the signal electrode at a rate of one;
An ultrasonic probe comprising: a third flexible printed circuit board having a lead electrode electrically connected to one end side of each of the plurality of electrode portions via a conductive member. 2. The ultrasonic probe according to claim 1, wherein the conductive member is a material obtained by dispersing silver particles in a resin material to obtain conductivity. Electrically connected to the ground electrodes of a plurality of piezoelectric vibrators each having a ground electrode formed on one surface side and a signal electrode formed on the other surface side and arranged in parallel at a predetermined interval Electrically connecting the first flexible printed circuit board;
At least two of the plurality of piezoelectric vibrators on the other end side of the second flexible printed circuit board in which a plurality of electrode portions having one end side formed in a substantially sharp shape are arranged in parallel at a predetermined interval. Electrically connecting the signal electrodes of the above piezoelectric vibrators at a rate of one;
And a step of electrically connecting a lead electrode of a third flexible printed circuit board to one end side of each of the plurality of electrode portions via a conductive member, respectively.

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