JP2000261056A - Laminated ceramic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated ceramic part and a method for manufacturing it, in which electrical joining accuracy and mechanical joining strength are enhanced at a low cost, when an internal electrode of a laminated part is joined to a cable from the outside. SOLUTION: When electricity is conducted from an internal electrode of a laminated ceramic part with the use of electric wires 6, 7, etc., a land pattern is formed using a junction electrode 4 of high viscosity properties, such as a carbon electrode as a junction point, to electrically join the electrical wires 6 and 7 to the internal electrode. Thereby the laminated ceramic part is provided for which electrical joining accuracy is high and mechanical joining strength with respect to a piezoelectric phenomenon is high.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer ceramic component having internal electrodes.

[0002]

2. Description of the Related Art Conventionally, there has been a piezoelectric bimorph as a multilayer ceramic component.

[0003] The piezoelectric bimorph is formed so that a piezoelectric ceramic element plate is adhered so as to sandwich a shim material serving also as an insulating and reinforcing plate such as glass fiber, and electric wires are taken out from both electrodes of each piezoelectric ceramic element plate. .

[0004] By applying a voltage to this piezoelectric ceramic element plate, the element is bent, and it is used in fields such as controlling the vibration needle of an embroidery machine, a knitting machine or a warp knitting machine.

Conventionally, in order to join and electrically conduct the electrodes of the piezoelectric ceramic element plate and the electric wires to be taken out, electric wires are conventionally pressed in a state where the electric wires are pressed against gold (Au) -plated internal electrodes on the piezoelectric ceramic. A technique is employed in which a shim material is attached and thermally cured by a filled adhesive. Further, as a method of increasing the bonding strength, there is soldering.

[0006]

However, when the electrode of the piezoelectric ceramic element plate and the electric wire to be taken out are joined and electrically connected, the electric wire is pressed against the conventional internal electrode and the adhesive filled in the shim material is used. In the method of thermosetting, a sufficient bonding area between the internal electrode and the electric wire cannot be obtained due to bending or twisting of the electric wire, or an adhesive filled in a shim material between the electric wire and the Au-plated internal electrode. However, there is a problem that the liquid crystal penetrates due to a capillary phenomenon and a poor electrical contact occurs at the time of manufacturing.

[0007] Further, since the piezoelectric bimorph is used in an intense operation such as controlling the vibrating needle of an embroidery machine, a knitting machine or a warp-striping machine, the piezoelectric bimorph presses an electric wire against an internal electrode and fills the shim material. When manufactured by a method of thermally curing with an agent, there is a problem that a gap is gradually formed between the electric wire and the Au-plated internal electrode due to stress due to repeated operation, resulting in poor electrical conduction.

[0008] To avoid these problems, the electric wire and A
There is also a method of soldering u-plated internal electrodes, but the stress on the ceramic element due to the heat generated by the melting of the solder at high temperature, the increase in cost due to the increase in the number of processes, the thickness at the solder joints The problem described above newly occurred, which was inconvenient.

[0009] Therefore, a technical problem of the present invention is to provide an internal electrode of a multilayer ceramic component such as a piezoelectric bimorph and an electric wire for taking out to the outside while maintaining a mechanical strength capable of withstanding the piezoelectric phenomenon and an electrical method by an easy method. An object of the present invention is to provide a multilayer ceramic component that can be joined and a method for manufacturing the same.

[0010]

According to the present invention, there is provided a laminated ceramic component having an internal electrode in a ceramic laminate, wherein the internal electrode and the electric wire are joined to each other by a bonding electrode containing a highly viscous conductive material. Through this process, a multilayer ceramic component having improved electrical bonding accuracy can be obtained.

According to the present invention, in the laminated ceramic component, the ceramic laminated body is made of a piezoelectric ceramic laminated body, and is further joined by a joining electrode made of the conductive material to further provide a mechanical joint for a piezoelectric phenomenon. A multilayer ceramic component characterized by increased strength is obtained.

Further, according to the present invention, in any one of the above-mentioned laminated ceramic parts, the laminated ceramic part is characterized in that the bonding electrode is substantially made of a carbon electrode.

According to the present invention, in a method of manufacturing a laminated ceramic component having an internal electrode in a ceramic laminate, the plated surface of a ceramic element plate plated to form an internal electrode on at least one surface is provided. To
A method of manufacturing a multilayer ceramic component, comprising: applying a highly viscous conductive substance to form a bonding electrode; and bonding an external wire through the bonding electrode to increase electrical bonding accuracy. Is obtained.

Further, according to the present invention, in the method for manufacturing a multilayer ceramic component, the ceramic laminate may include:
A method of manufacturing a laminated ceramic component, comprising a piezoelectric ceramic laminate and further increasing mechanical bonding strength against piezoelectric phenomena by joining with the joining electrode made of the conductive substance, is obtained.

Further, according to the present invention, in the method for manufacturing a multilayer ceramic component, a method for manufacturing a multilayer ceramic component, wherein the bonding electrode substantially comprises a carbon electrode is obtained.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, taking a piezoelectric ceramic bimorph as an example of a laminated ceramic component.

FIG. 1 is a schematic perspective view showing the structure of a piezoelectric ceramic bimorph according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view of the piezoelectric ceramic bimorph of FIG. FIG. 3 is a sectional view of the piezoelectric ceramic bimorph of FIG.

As shown in FIGS. 1 to 3, the basic structure of the piezoelectric ceramic bimorph 10 is such that a piezoelectric phenomenon occurs when a voltage is applied, and the element dimensions change. , 2 and a shim 3 made of glass fiber sandwiched between the piezoelectric ceramic element plates 1 and 2 and serving as an insulating and reinforcing plate between the two elements, and a voltage is applied to the piezoelectric ceramic element plates 1 and 2. In order to achieve this, the wires 6 and 7 for external connection to be connected to the piezoelectric ceramic element plates 1 and 2 and the carton paste for increasing the connection strength are applied to the bonding electrodes 4 and 5 in an E-shape. . Gold plating films 1a, 2 formed on the inner facing surfaces of the piezoelectric ceramic element plates 1, 2
a forms an internal electrode.

In the piezoelectric ceramic bimorph 10 according to the first embodiment of the present invention having such a structure, the gold-plated films 1a and 2a as the internal electrodes and the electric wires 6 and 7 are joined with a highly viscous joint such as a carbon electrode. By performing via the electrodes 4 and 5, a sufficient bonding area of the electric wires 6 and 7 cannot be obtained, or the shim material 3 is filled between the electric wires 6 and 7 and the Au-plated internal electrode. This prevents the adhesive from penetrating due to the capillary phenomenon and causing electrical contact failure at the time of manufacturing. In addition, in the case of a piezoelectric bimorph, etc., the wire between the electric wire and the Au-plated internal electrode is subjected to stress due to repeated operation. In this case, it is possible to prevent a problem that an electric connection failure occurs due to a gradual gap, and it is possible to increase an electric joining accuracy and a mechanical joining strength against a piezoelectric phenomenon.

It should be noted that the shim material 3 is not limited to a glass fiber shim material containing an adhesive, such as a glass epoxy, as in the present embodiment, as long as it functions as an adhesive.

FIG. 4 is a schematic perspective view showing the structure of a piezoelectric ceramic bimorph as a piezoelectric ceramic part according to a second embodiment of the present invention. FIG. 5 is an exploded perspective view of the piezoelectric ceramic bimorph of FIG. FIG. 6 is a sectional view of the piezoelectric ceramic bimorph of FIG.

As shown in FIGS. 4 and 5, the basic structure of the piezoelectric ceramic bimorph 11 is such that when a voltage is applied, a piezoelectric phenomenon occurs and the element dimensions change. , 2 and a shim 3 made of glass fiber which is sandwiched between the piezoelectric ceramic element plates 1 and 2 and serves as an insulating and reinforcing plate between the two elements, and a voltage is applied to the piezoelectric ceramic element plates 1 and 2. Wires 6 and 7 connected to ceramic element plates 1 and 2
And a bonding electrode 4 ′, 5 ′ made of a carbon paste applied in a rectangular shape to one end of the opposing surfaces of the ceramic element plates 1, 2 to increase the connection strength. The internal electrodes are formed by gold plating films 1a and 2a applied to the opposing surfaces of the ceramic element plates 1 and 2, respectively.

In the piezoelectric ceramic bimorph 11 according to the second embodiment of the present invention having the above-described structure, similarly to the first embodiment, the connection between the internal electrode and the electric wires 6 and 7 is made by using a viscous material such as a carbon electrode. By performing the bonding via the high bonding electrode 4, the bonding area of the electric wires 6 and 7 may not be sufficiently obtained, or the shim material 3 may be filled between the electric wires 6 and 7 and the Au-plated internal electrode. It is possible to prevent a problem that an existing adhesive infiltrates due to a capillary phenomenon and causes poor electrical contact at the time of manufacturing.

In a piezoelectric bimorph or the like, a gap is gradually formed between the electric wire and the Au-plated internal electrode due to the stress caused by the repetitive operation, and the problem of poor electrical conduction can be prevented. Mechanical bonding strength against piezoelectric phenomena can be increased.

Next, specific examples of the piezoelectric ceramic bimorph according to the first and second embodiments of the present invention will be described.

Example 1 First, referring to FIGS. 1 to 3,
Au plating is applied to the piezoelectric ceramic element plates 1 and 2 to form electrodes on the front and back surfaces of the elements. Next, a carbon paste is applied to an E-shaped land shape extending from a portion where an electric wire contacts the element after the formation of the Au plating to a tip end of the element,
Baking is performed to form bonding electrodes 4 and 5 for strengthening the wire bonding strength.

Thereafter, the electric wires 6 and 7 and the piezoelectric ceramic element plates 1 and 2 are attached to each other so as to sandwich the glass fiber shim material 3 and are pressed and thermocompressed.

Example 2 First, referring to FIGS. 4 to 6,
Au plating is applied to the piezoelectric ceramic element plates 1 and 2 to form electrodes on the front and back surfaces of the elements. Next, a carbon paste is applied in a land shape to a portion where the wires 6 and 7 come into contact with the element after the formation of the Au plating, and baking is performed to form bonding electrodes 4 ′ and 5 ′ for strengthening the wire bonding strength. After that, the electric wires 6 are sandwiched between the glass fiber shim members 3.
7 and the piezoelectric ceramic element plates 1 and 2 are adhered and pressed and thermocompressed.

Example 3 First, as shown in FIGS. 1 to 3, Au plating was applied to the piezoelectric ceramic element plates 1 and 2,
Electrodes are formed on the front and back surfaces of the device. Next, a carbon paste is applied to an E-shaped land extending from a portion where the wire contacts the element after the formation of the Au plating to a tip end of the element to form bonding electrodes 4 and 5 for strengthening the wire bonding strength.
Thereafter, the electric wires 6 and 7 and the piezoelectric ceramic element plates 1 and 2 are attached to each other with the glass fiber shim 3 interposed therebetween, pressurized, and thermally cured together with the carbon paste.

(Example 4) First, as shown in FIGS. 4 to 6, Au plating was applied to the piezoelectric ceramic element plates 1 and 2,
Electrodes are formed on the front and back surfaces of the device. Next, a carbon paste is applied in a land shape to portions where the wires 6 and 7 come into contact with the elements after the formation of the Au plating, to form bonding electrodes 4 ′ and 5 ′ for reinforcing wire bonding strength. Thereafter, the electric wires 6, 7 and the piezoelectric ceramic element plates 1, 2 are adhered to each other so as to sandwich the shim material 3 made of glass fiber.

In order to compare the piezoelectric bimorph manufactured as described above with the piezoelectric bimorph manufactured by the conventional method, the following performance test was performed.

(First Test) In order to confirm the effect of improving the electrical joining accuracy, a continuity test was performed between the ceramic element and the electric wires 5 and 6 using the piezoelectric bimorph manufactured according to the present invention and the piezoelectric bimorph manufactured according to the conventional method. The continuity failure rate at the time of manufacture was compared. In the present invention, as in Example 2 above,
In one of the above-mentioned examples 2, the one having at least one rectangular bonding electrode at one end of one surface was used, and the conventional method was used.
Without using the bonding electrodes, the wires 5 and 6 were directly pressed against the gold plating film, and the adhesive was heated and cured together with the shim material 3. The results are shown in Table 1 below.

[0033]

[Table 1]

From Table 1 above, it can be seen that the device according to the present invention has a clearly lower defect rate and better quality than the device according to the conventional method.

(Second Test) In order to confirm the effect of improving the mechanical bonding strength, the same piezoelectric bimorph as the sample of the present invention used in the first test in which the electric wires were bonded via a carbon paste and the second test was used. A repetitive operation test was performed with a ceramic element using the same piezoelectric bimorph as the sample according to the conventional method used in the test No. 1, and the rate of conduction failure with respect to the number of operations was compared.

FIG. 7 shows the result. As can be seen from FIG. 7, the piezoelectric bimorph according to the method of the present invention has a significantly smaller number of failures than the piezoelectric bimorph according to the conventional method.

[0037]

As described above, according to the present invention,
A multilayer ceramic component having at least an internal electrode in a ceramic laminate and having a structure for drawing an electric wire from the internal electrode to the outside, in which the internal electrode and the electric wire are joined via a highly viscous electrode such as a carbon electrode. Thus, it is possible to provide a multilayer ceramic component having high electrical bonding accuracy and high mechanical bonding strength against a piezoelectric phenomenon.

Further, according to the present invention, in a laminated ceramic component having an internal electrode, a highly viscous carbon electrode or the like is applied to a plated ceramic element, and the internal electrode and the electric wire are joined by a carbon electrode or the like. By using a highly viscous electrode, it is possible to obtain a method of manufacturing a multilayer ceramic component having high electrical bonding accuracy and high mechanical bonding strength against a piezoelectric phenomenon.

[Brief description of the drawings]

FIG. 1 is a perspective view of a piezoelectric ceramic bimorph according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the piezoelectric ceramic bimorph of FIG. 1;

FIG. 3 is a sectional view of the piezoelectric ceramic bimorph of FIG. 1;

FIG. 4 is a perspective view of a piezoelectric ceramic bimorph according to a second embodiment of the present invention.

FIG. 5 is an exploded perspective view of the piezoelectric ceramic bimorph of FIG. 4;

FIG. 6 is a cross-sectional view of the piezoelectric ceramic bimorph of FIG.

FIG. 7 is a diagram showing a test result of a mechanical bonding strength of a piezoelectric ceramic bimorph according to an embodiment of the present invention, and also shows a test result of a piezoelectric ceramic bimorph according to a conventional method for comparison.

[Explanation of symbols]

 1, 2 Piezoelectric ceramic element plate 3 Shim material 4, 4 ', 5, 5' Joint electrode 6, 7 Electric wire 10, 11 Piezoelectric ceramic bimorph

Claims (6)

[Claims] 1. A multilayer ceramic component having an internal electrode in a ceramic laminate, wherein the internal electrode and an electric wire are joined via a joining electrode containing a highly viscous conductive material, thereby providing electrical joining. Multilayer ceramic parts characterized by improved accuracy. 2. The multilayer ceramic component according to claim 1, wherein the ceramic laminate is made of a piezoelectric ceramic laminate, and further has a mechanical joining strength against a piezoelectric phenomenon by being joined by a joining electrode made of the conductive material. Multilayer ceramic parts characterized by increased 3. The multilayer ceramic component according to claim 1, wherein the bonding electrode substantially comprises a carbon electrode. 4. A method of manufacturing a laminated ceramic component having an internal electrode in a ceramic laminate, wherein said plated surface of a ceramic element plate plated to form an internal electrode on at least one surface is provided with a highly viscous conductive material. A method for producing a multilayer ceramic component, comprising: applying a conductive substance to form a bonding electrode; and bonding an external wire through the bonding electrode to increase electrical bonding accuracy. 5. The method for manufacturing a multilayer ceramic component according to claim 4, wherein said ceramic laminate is made of a piezoelectric ceramic laminate, and is further mechanically protected against piezoelectric phenomena by bonding with a bonding electrode made of said conductive material. A method for manufacturing a multilayer ceramic component, characterized by also increasing bonding strength. 6. The method for manufacturing a multilayer ceramic component according to claim 4, wherein the bonding electrode is substantially composed of a carbon electrode.