JPS6385353A - Array probe - Google Patents

Abstract

PURPOSE:To dispense with a process for cutting piezoelectric ceramics, by laminating a large number of thin plates composed of piezoelectric ceramics by an insulating adhesive and slicing said thin plates in the direction perpendicular to the surfaces of said thin plates. CONSTITUTION:Thin plates 2 composed of unpolarized piezoelectric ceramics are laminated by an insulating adhesive 3 to form square pillar-shaped laminated ceramics 1. Next, the laminated ceramics 1 is sliced in the direction vertical to the surfaces of the thin plates 2 to obtain a ceramic flat plate 4. After the ceramic flat plate 4 is processed so as to have a dimension necessary for an array probe, electrodes 5 are formed to the ceramic flat plate 4 by the printing, vapor deposition or sputtering of a silver paste and only the single side electrode 5 is divided by etching. Then, polarizing treatment is performed and a lead is taken from each vibrator to be adhered to a backing material. By this method, the cutting of the piezoelectric ceramics becomes unnecessary and the miniaturization of the array vibrator becomes easy.

Description

Detailed Description of the Invention (Objective of the Invention) (Industrial Field of Application) The present invention is an ultrasonic flaw detection device that is a medical device or a non-destructive testing device. The present invention relates to an array probe used in ultrasound equipment that displays tomographic images.

(Prior Art) An array probe has a structure in which rectangular transducers are arranged one-dimensionally, and each transducer is attached with a lead wire so that it can be selectively driven. Generally, the vibrator is made of piezoelectric ceramic and is fixed to a backing material to suppress vibration ringing (Figure 6).

To manufacture this array probe, piezoelectric ceramics of approximately the same size are bonded to a backing material, and then only the piezoelectric ceramics are cut in a direction perpendicular to the longitudinal direction using a cutting machine such as a dicer. That is, it has a structure in which rectangular vibrators are arranged one-dimensionally.

Connect the signal lead wires to the electrodes (
The transducer is attached to the backing (adhesive surface) at the cutting pitch of the transducer, and the GND side leads are pulled out by connecting the electrodes on the top surface of the transducer in common.

The driving frequency of an array probe depends on the thickness of the transducer, and in the case of a probe of several MHz, the thickness of the transducer is several hundred microns. In the case of a rectangular vibrator, the transverse imaging mode in the width direction influences the thickness vibration mode in the range from tω to tω when the width ω of the vibrator is 1). Since it has an adverse effect on the characteristics of the child, it is generally made under the condition of ω/lo, 6. Generally, the width of one transducer of an array probe is 1 to 2#, so one sensor has a width of ω/
It is further divided to meet the condition l<0.6.

Therefore, the number of cuttings required to make an array probe is the product of the number of array probes and the number of divisions of one sensor, which is a fairly large number. FIG. 7 shows an example in which the vibrator shown in FIG. 6 is divided into three parts. Further, the width of one divided ceramic rod constituting the array sensor becomes narrower as the frequency increases, and at about 10 MHz, the width becomes about 100 μ. When such a thin cutting process is performed, the mechanical strength of the piezoelectric ceramic becomes weak and it becomes easily damaged. In addition, the properties of piezoelectric ceramics deteriorate due to heat and strain caused by processing, and the effects of this are becoming greater.

(Problems to be Solved by the Invention) As mentioned above, array probes that are conventionally made using a cutting process require several hundred cutting processes, and the mechanical strength and processability of piezoelectric ceramics There is a limit to the dimensions that can be cut due to deterioration of characteristics due to this, and it was difficult to cut into a width of about 100 μm.

The present invention aims to provide a piezoelectric vibrator that does not require cutting when manufacturing an array probe, and satisfies the condition of ω/l<0.6 without the influence of transverse modes. IO
It is also possible to provide a vibrator that satisfies MH2 or higher.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides an electronic scanning type ultrasonic diagnostic device and an array probe used in an ultrasonic flaw detection device, in which a large number of piezoelectric ceramic thin plates are laminated with an insulating adhesive. , is characterized in that the vibrator is constructed by slicing the thin plate in a direction perpendicular to the surface thereof. Thin plates of piezoelectric ceramic are formed by a doctor blade method or the like, and are laminated with an insulating adhesive without providing electrodes or polarization to form a prismatic shape. The plane of the ceramic thin plate is perpendicular to the longitudinal direction of the prism. This prism is sliced parallel to the longitudinal direction to form a flat plate.

In other words, the array probe is manufactured by cutting, and the cut edges of the ceramic are filled with adhesive to form an image sensor. By forming electrodes on this and polarizing it, an array probe that does not require cutting can be created. A piezoelectric vibrator for a probe can be provided.

(Function) The piezoelectric vibrator of the present invention has a configuration in which rectangular piezoelectric ceramics required for an array probe are bonded to each other horizontally and with adhesive, and can be used several hundred times by dividing only the electrodes. Array probes can be constructed without the need for extensive cutting. Also.

With the doctor blade method, thin plates with a thickness of 100 JiIn or less can be easily manufactured, so even high-frequency vibrators can be obtained without any problems due to the effects of transverse modes.

(Example) A typical manufacturing method of the array probe vibrator of the present invention will be described. As shown in FIG. 1, unpolarized piezoelectric ceramic thin plates 2 made by a doctor blade method or the like are laminated with an insulating adhesive 3 to form a prismatic laminated ceramic 1. Second
1 shows the structure of the ceramic thin plate and adhesive in an enlarged view of FIG. Next, the laminated ceramic 1 is sliced in the direction perpendicular to the surface of the ceramic thin plate 2, and the ceramic flat plate 4 shown in FIG.
get. FIG. 4 is an enlarged view of FIG. 3. The ceramic flat plate 4 thus manufactured is in the form of a conventional array probe in which adhesive is embedded in the cut grooves of the cut and divided carrier rows. There is. After the ceramic flat plate 4 is processed to the required dimensions as an array probe, only the electrode 5 on one side is divided to serve as the signal side electrode, as shown in Fig. 5, and the entire surface of the other side is connected to GND.
A side electrode 5 is provided. This N-pole 5 may be formed by printing silver paste or vapor-depositing sandbatter, and then divided by etching. The width ω of one strand in FIG. 4 corresponds to the thickness of the laminated ceramic thin plates, and the thickness t can be controlled by the width of the slice and its appropriate polishing process. After forming the electrodes shown in FIG. 5, a polarization process is performed to complete the array probe vibrator. By taking leads from each vibrator and bonding them to a backing material, an array probe configuration as shown in FIG. 7 can be obtained without cutting.

In the present invention, adhesive is buried in the cut grooves of the conventional example shown in Fig. 7, but in general, an input/4 matching layer is provided on the ultrasonic transmission/reception wave surface to achieve acoustic matching with the load medium. Due to this adhesion, even in the conventional example, the cut grooves are filled with adhesive. Furthermore, in the present invention, by using a flexible polymeric material such as silicone rubber for the insulating adhesive, it is possible to provide flexibility in the longitudinal direction of the flat plate shown in FIG. This is advantageous in manufacturing array probes with

(Effects of the Invention) The sensor of the present invention eliminates the need for a piezoelectric ceramic cutting process in manufacturing an array probe, and can solve problems in the cutting process. This improves the yield, and as the frequency of probes increases, array transducers are becoming smaller and smaller, and can be easily provided even in minute dimensions that are not possible with conventional methods.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a laminate of piezoelectric ceramic thin plates that serve as the base of the vibrator of the present invention, FIG. 2 is an enlarged view of FIG. 1, and FIG.
The figure shows the external appearance of the vibrator of the present invention, FIG. 4 is an enlarged view thereof, and FIG. 5 is a diagram showing the electrodes formed in FIG. 4.
FIGS. 6 and 7 are diagrams showing an imager of a conventional array probe. 1... Laminated body 2... Piezoelectric ceramic thin plate 3... Insulating adhesive 4... Camera plate 5...
Electrical t'I 6...Camera element 7...Cutting groove 8...Backing material 9...Lead wire agent Patent attorney Nori Chika Ken Yudo Takehana Kikuo Figure 6 Figure 7

Claims (1)

[Claims] 1) In an array probe used in electronic scanning type ultrasonic diagnostic equipment and ultrasonic flaw detection equipment, a large number of piezoelectric ceramic thin plates are laminated with an insulating adhesive, and the thin plates are laminated with an insulating adhesive. An array probe characterized in that a transducer is formed by slicing the transducer in a direction perpendicular to the surface. 2) The array probe according to claim 1, wherein the thickness of the ceramic thin plate laminated with the piezoelectric vibrator is thinner than the thickness of the piezoelectric vibrator.