JPH0295356A - Manufacture of ultrasonic probe - Google Patents

Abstract

PURPOSE:To facilitate manufacture and, simultaneously, to obtain an excellent acoustic characteristic by curving an original panel to be longitudinally and laterally cut in a prescribed curvature along the arranging direction of one part cut groove, thereafter, filling the one part cut groove with a resin, and solidifying it. CONSTITUTION:An original panel 36 is prepared in which full-face electrodes 32 and 34 are formed on both upper and lower surfaces of a piezoelectric substrate 30, and a plate separation-proofing plate 38 and a signal line 18 are fixed. The original panel 36 is cut in a prescribed pitch in the lateral direction, a total cut groove 4 in a depth up to the separation-proofing plate 38 is formed, the total cut groove 4 is filled with a resin 10, and it is solidified. Next, the original panel 36 is cut in the prescribed pitch in the longitudinal direction orthogonal to the arranging direction of the total cut groove 4, and the piezoelectric substrate 30 is left uncut. Then, the separation- proofing plate 38 is removed, the original panel 36 is placed on a supporting base 40 having a circular arc recessed surface 40a, and then, the original panel 36 is curved along the longitudinal direction. In such a case, a one part cut groove 6 is filled with the resin and solidified. The supporting base 40 is removed, and a full-face electrode 42 for grounding is provided on the upper surface of the original panel.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention is applicable to structures in which transducers are arranged in an arc shape, such as a convex type ultrasonic probe or a cone-cape type ultrasonic probe. The present invention relates to a method of manufacturing an ultrasonic probe.

(b) Prior art and its problems In general, ultrasonic probes that have an arc shape in the short axis direction as described above have advantages such as being able to set the focus without using an acoustic lens. be.

When manufacturing such an ultrasonic probe, conventionally, a single ceramic panel is prepared in advance by sintering into a curved shape, is bonded to a curved backing material, and then the ceramic panel is cut and separated. A method is provided.

However, this method has drawbacks such as the fact that a regular flat panel dicing saw cannot be used to cut and separate arc-shaped panels, requires special equipment, and increases manufacturing costs. There is. .

In addition, in the conventional structure, in order to scan the ultrasonic waves, the piezoelectric element is simply cut at a predetermined pitch along the ultrasonic scanning direction, so the electromechanical conversion efficiency is still insufficient, and the There are problems such as difficulty in impedance matching with the specimen.

Therefore, the present applicant has developed a method in which polarized planar ceramic panels are connected together by connecting portions.
A large number of ceramic pieces are cut and separated, and then an adhesive that becomes flexible when solidified is filled between the ceramic pieces and solidified.Subsequently, the above-mentioned connecting parts are removed and the ceramic pieces are bonded together. The present invention provides a method for manufacturing an ultrasonic probe in which a bendable composite panel connected by a bonding agent is obtained, and an electrode is attached to this composite panel (Japanese Patent Application No. 1986-202).
(See No. 178).

The applicant further investigated this manufacturing method and found that the following problems remained. That is, in the above manufacturing method, since it is necessary to use an adhesive that exhibits flexibility after solidification, the type of adhesive to be used is limited, and the acoustic characteristics are therefore restricted. In addition, since each ceramic piece is completely separated, if the composite panel is bent when bonded to the back layer, the pitch of each ceramic piece tends to be disturbed, and the beam direction may not be set accurately. be. Furthermore, after the formation of the composite panel,
Since electrodes are formed on both sides at a predetermined pitch and signal lines are attached, alignment is time-consuming and adjustment is troublesome.

The present invention has been made in view of the above circumstances, and is a method for manufacturing an ultrasonic probe in which piezoelectric elements are arranged in an arc shape, which further simplifies the manufacturing process compared to the conventional method, and The purpose is to obtain something with excellent acoustic characteristics.

(c) Means for solving the problems In order to achieve the above object, the present invention adopts the following configuration.

That is, in the method for manufacturing an ultrasonic probe of the present invention, an original panel is prepared in which electrodes are formed on the entire surface of the lower surface of a polarized flat piezoelectric substrate, and a separation prevention plate and a separation prevention plate are provided on the lower surface of this original panel. After attaching the signal wires, cut the original panel in the horizontal direction at a predetermined pitch to form a full cut groove with a depth that reaches the separation prevention plate, fill the full cut groove with resin,
After solidifying, the entire original panel is cut at a predetermined pitch in the vertical direction perpendicular to the arrangement direction of the cutting grooves to form cutting grooves with a depth that leaves the piezoelectric substrate uncut. After the cut original panel is curved at a predetermined curvature along the arrangement direction of the partially cut grooves, under this condition, the partially cut grooves are filled with resin and solidified, and then the original panel is A curved vibrator is obtained by forming an entire surface electrode for grounding on the upper surface, and a back layer having a bonding surface previously formed in an arc shape along the shape of the curved vibrator is fixed to the lower surface of the curved vibrator.

(D) Function According to this manufacturing method, after partially bending the original panel at a predetermined curvature along the arrangement direction of the cut grooves, under this condition, resin is filled into the partially cut grooves and solidified. However, it is not necessary to select and use an adhesive that is flexible after solidification, and any adhesive that can be filled and solidified may be used, which widens the range of choices for the filling resin.

In addition, since some of the ceramic pieces are connected together without being separated along the arrangement direction of the cutting grooves, the pitches of the ceramic pieces are the same even when the original panel is curved.

Furthermore, after the curved vibrator is formed, it is only necessary to form a full-surface grounding electrode on its upper surface, so there is no need for subsequent cutting of the electrode or attachment of signal lines.

(E) Example FIG. 1 is a perspective view of an ultrasonic probe curved concavely in the minor axis direction obtained by the manufacturing method of the present invention, and FIG. 2 is a partially enlarged perspective view thereof.

In these figures, l indicates the entire ultrasound probe,
2 is a curved vibrator. This curved vibrator 2 is arranged in the lateral direction (
A rectangular cross section is formed by fully cut grooves #4 arranged at a predetermined pitch along the longitudinal direction (long axis direction) and partially cut grooves 6 arranged at a predetermined pitch along the longitudinal direction (short axis direction) perpendicular to this. A large number of short column-shaped ceramic pieces 8 are formed, and resin lO is filled and solidified between the ceramic pieces 8. In this case, when viewed in the horizontal direction, the ceramic pieces 8 are completely separated from each other by the above-mentioned cutting grooves 4, but when viewed in the arrangement direction (vertical direction) of the partial cutting grooves 6, they are not separated but are integrally connected. ing. A whole surface electrode 12 for grounding is formed on the upper surface of the ceramic piece 8, and individual electrodes 14 for applying a signal are formed on the lower surface of the ceramic piece 8, all of which are individually separated by cutting grooves 4.

A matching layer 16 is provided on the upper surface of the curved vibrator 2, and
On the lower surface of the curved vibrator 2, a signal line 18 such as an FPC is electrically connected to the individual electrode 14, and a back layer 20 having an arc-shaped concave surface is adhesively fixed. In addition, 22
is the case.

Next, the manufacturing process of the ultrasonic probe 1 will be sequentially explained based on the explanatory diagram of the manufacturing method shown in FIG.

First, an original panel 36 is prepared by forming electrodes 32 and 34 on the entire surface of the polarized flat piezoelectric substrate 30 on both upper and lower surfaces (see FIG. 3C).

Note that the entire surface electrode 32 on the upper surface of the original panel 36 may be omitted.

Next, a flat separation prevention plate 38 and a signal line (FPC in this example) 18 for separation prevention and positioning during cutting in the next process are fixed to the lower surface of this original panel 36 (see FIG. 3). Then, the original panel 36 is cut in the transverse direction at a predetermined pitch to form cutting grooves 4 having a depth up to the separation prevention plate 38.

By this whole cutting WI#4, individual electrodes 14 for applying signals are formed on the lower surface of the original panel 36. Then, all of the cutting grooves 4 are filled with resin lO such as adhesive and solidified (see FIG. 3C).

Next, the entire original panel 36 was cut at a predetermined pitch along the vertical direction perpendicular to the arrangement direction (horizontal direction) of the cutting grooves 4, leaving the piezoelectric substrate 30 uncut (thickness indicated by t in FIG. 2). form a cutting groove 6 with a partial depth (3rd
(See Figure C). As a result, a large number of short columnar ceramic pieces 8 having a rectangular cross section are formed. In this case, each ceramic piece 8 is completely separated from each other by the above-mentioned cutting grooves 4, but some of them are not separated along the arrangement direction (vertical direction) of the cutting grooves 6 but are integrally connected.

Subsequently, the separation prevention plate 38 bonded to the lower surface of the original panel 36 is removed, and then the original panel 36 is placed on a support stand 40 having an arcuate concave surface 40a that matches the bonding surface of the back layer 20 that will be attached in a later process. Place. In this case, the original panel 34 partially has flexibility in the arrangement direction (vertical direction) of the cutting grooves 6, so it curves along the longitudinal direction. Therefore, in this state, some of the cutting grooves 6 are filled with resin and solidified (Fig. 3C).
reference).

Next, the support stand 40 is removed, and the entire surface electrode 12 for grounding is provided on the upper surface of the original panel 36 (see FIG. 3C). This is formed by attaching a conductive film 42 using a conductive adhesive. In this way, the curved vibrator 2
is obtained.

Therefore, next, a back layer 2° having a joint surface 20a formed in an arc shape in advance is fixed to the lower surface of the curved vibrator 2 (see FIG. 3). 16
will be established. In this way, the desired ultrasonic probe 1 is completed.

In the above example, a method for manufacturing an ultrasonic probe that is curved concavely in the short axis direction has been described, but it is also possible to manufacture an ultrasonic probe that has transducers arranged in an arc, such as a convex type. Of course, the present invention can be applied to the manufacturing method. Further, in this embodiment, the original panel 3 is mounted on the support stand 38.
However, if the separation prevention plate 38 is made of a thin sheet or the like, the curved vibrator can be removed without removing the separation prevention plate 38. It is also possible to assemble 2.

(f) Effects According to the present invention, there is no need to use an adhesive that has flexibility after assimilation, so there is more room for selection of filling resins. Therefore, the type of filling resin can be selected depending on the desired characteristics of the sound bottle. In addition, since some of the ceramic pieces are not separated along the arrangement direction of the cutting grooves but are integrally connected, even when the ceramic pieces are curved, the pitches of the ceramic pieces are the same.

Therefore, a highly accurate probe structure is possible. Furthermore, since it has a composite piezoelectric structure, acoustic matching with the human body is easy. Furthermore, after forming the curved vibrator, it is sufficient to simply form a full-surface electrode for grounding on its upper surface.

Therefore, the manufacturing process becomes simpler than in the past, and excellent effects such as being able to obtain an ultrasonic probe with excellent acoustic characteristics are exhibited.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, and FIG. 1 is a perspective view of an ultrasonic probe obtained by the manufacturing method of the present invention, and FIG.
The figure is an enlarged perspective view of the same main part, and FIG. 3 is an explanatory view showing the manufacturing process of the present invention. 1... Ultrasonic probe, 2... Curved transducer, 4...
All cutting grooves, 6...Partial cutting grooves, 8...Ceramic piece, IO...Resin, 12...Full surface electrode, 14...
Individual electrode, 16... matching layer,

Claims (1)

[Claims] (1) Prepare an original panel with electrodes formed on the entire surface of the lower surface of a polarized flat piezoelectric substrate, attach a separation prevention plate and a signal line to the lower surface of this original panel, and then turn the original panel horizontally. All cut grooves with a depth reaching the separation prevention plate are formed by cutting at a predetermined pitch in the direction, resin is filled and solidified in all the cut grooves, and then the original panel is cut in the direction in which all the cut grooves are arranged. The piezoelectric substrate is cut at a predetermined pitch in the orthogonal vertical directions to form partially cut grooves with a depth that is left uncut, and then the original panel cut vertically and horizontally is cut along the arrangement direction of the partially cut grooves. After bending it to a predetermined curvature, in this state, the partially cut grooves are filled with resin and solidified, and then a full-surface electrode for grounding is formed on the upper surface of the original panel to obtain a curved vibrator. A method for manufacturing an ultrasonic probe, comprising fixing to the lower surface of the curved transducer a back layer having a bonding surface previously formed in an arc shape along the shape of the curved transducer.