JP3316556B2 - Piezoelectric resonator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric resonator, and more particularly, to a piezoelectric resonator utilizing a longitudinal vibration and used for, for example, an oscillator or a filter.

[0002]

2. Description of the Related Art An example of a conventional piezoelectric resonator is disclosed in
No. 9627. FIG. 7 is an illustrative view showing one example of such a conventional piezoelectric resonator. The piezoelectric resonator 1 shown in FIG. The resonance element 2 includes a strip-shaped piezoelectric substrate 3 polarized in the thickness direction. On one main surface side of the piezoelectric substrate 3, a groove 4 is formed at the center in the width direction. The groove 4 is for suppressing spurious due to the width of the piezoelectric substrate 3. On one main surface of the piezoelectric substrate 3, two main surface electrodes 5 are provided on both sides of the groove 4.
a and 5b are formed respectively. Another main surface electrode 5c is formed on the other main surface of the piezoelectric substrate 3. The two main surface electrodes 5a and 5b of the resonance element 2 are adhered to a lead electrode 7a on one main surface of the insulating substrate 6 with a conductive paste 8, and are electrically connected to the lead electrode 7a. Further, another main surface electrode 5c of the resonance element 2 is electrically connected to another extraction electrode 7b on one main surface of the insulator substrate 6 by soldering a metal wire 9. The resonance element 2 is covered with a metal cap (not shown).

[0003]

However, in the piezoelectric resonator 1 shown in FIG. 7, the metal wire 9 is used to electrically connect the main surface electrode 5c of the resonance element 2 and the extraction electrode 7b on the insulating substrate 6. It requires the technique of wiring and requires a large investment in equipment for the wiring and a large space for installing and using the equipment.

Further, in the piezoelectric resonator 1 shown in FIG. 7, the main surface electrode 5c of the resonance element 2 is
Since it is electrically connected to the upper extraction electrode 7b, an area for the extraction electrode 7b to which the metal wire 9 is soldered is required for the insulator substrate 6 in addition to the area for bonding the resonance element 2, thus completing the process. The dimensions become larger than necessary.

[0005] Therefore, a main object of the present invention is to provide a piezoelectric resonator which does not require metal wires and can reduce the area of an insulating substrate.

[0006]

According to the present invention, there is provided a piezoelectric resonator having a resonance element, wherein the resonance element has a groove formed on one main surface side and is polarized in a thickness direction.
Two main surface electrodes formed on both sides of the groove on one main surface of the piezoelectric substrate, another main surface electrode formed on the other main surface of the piezoelectric substrate, and a node portion of the piezoelectric substrate. A conductive paste, which is formed and is a conductive member for electrically connecting the two main surface electrodes , is formed so as to straddle the groove.
An insulator whose one main surface faces the side surface of the piezoelectric substrate.
A substrate, formed on one main surface of the insulator substrate;
One of the main surface electrodes is fixed with a conductive member.
Extraction electrode, and one main surface of the insulator substrate
And the another main surface electrode is fixed by a conductive member.
Of the piezoelectric resonator.

[0007]

In the piezoelectric resonator according to the present invention, it is preferable that the resonance element be covered with a cap for the reasons described below.

[0009]

The two main surface electrodes on both sides of the groove on one main surface of the piezoelectric substrate of the resonance element and another main surface electrode on the other main surface of the piezoelectric substrate are connected to one main surface of the insulator substrate. In order to electrically connect to the extraction electrode and another extraction electrode, respectively, the two main surface electrodes are electrically connected by a conductive member. Another main surface electrode may be bonded to the extraction electrode and another extraction electrode using, for example, a conductive paste. Therefore, a metal wire is not required for electrically connecting the main surface electrode of the resonance element and the extraction electrode on the insulator substrate.

Also, since the main surface electrode of the resonance element is electrically connected to the lead electrode on the insulator substrate, it is not necessary to solder a metal wire to the lead electrode on the insulator substrate. Can be reduced in area.

[0011]

According to the present invention, it is possible to obtain a piezoelectric resonator which does not require metal wires and can reduce the area of the insulating substrate. Therefore, in the piezoelectric resonator according to the present invention, the material of the metal wire can be reduced, and a wiring device for the metal wire becomes unnecessary.

In the piezoelectric resonator according to the present invention, if the resonance element is covered with the cap, the resonance element is protected from the outside.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments of the present invention with reference to the accompanying drawings.

[0014]

FIG. 1 is a perspective view showing an example of an embodiment of the present invention, and FIG. 2 is an exploded perspective view thereof.
The piezoelectric resonator 10 shown in FIGS. 1 and 2 includes a resonance element 12.

The resonance element 12 includes a strip-shaped piezoelectric substrate 14 polarized in the thickness direction. On one main surface side of the piezoelectric substrate 14, a groove 16 is formed at the center in the width direction.
The groove 16 is for suppressing spurious due to the width of the piezoelectric substrate 14.

On one main surface of the piezoelectric substrate 14, two main surface electrodes 18a and 18b are formed on both sides of the groove 16, respectively. Further, on the other main surface of the piezoelectric substrate 14,
Another main surface electrode 18c is formed.

On one main surface of the node portion of the piezoelectric substrate 14, that is, on one main surface of the central portion in the longitudinal direction of the piezoelectric substrate 14, a conductive paste 20 as a conductive member extends from the main surface electrode 18 a so as to extend over the groove 16. The two main surface electrodes 1 are formed over the main surface electrode 18b, and the conductive paste 20 forms the two main surface electrodes 1
8a and 18b are electrically connected.

The main surface electrodes 18a and 18c of the resonance element 12 are connected to the lead electrodes 24a and 24b on one main surface of the insulating substrate 22 by the conductive pastes 26a and 26b.
And lead electrodes 24a and 24b
Are electrically connected to each other. In this case, the resonance element 1
The side surface of the second piezoelectric substrate 14 faces one main surface of the insulating substrate 22.

The resonance element 12 is formed of a metal cap 2.
8 and the end of the cap 28 is adhered to one main surface of the insulator substrate 22.

Next, an example of a method for manufacturing the piezoelectric resonator 10 will be described.

First, as shown in FIG. 3, a parent substrate 13 made of a piezoelectric material is prepared. The parent substrate 13 is to be a plurality of piezoelectric substrates 14, and has a width that is at least a multiple of the width of the piezoelectric substrate 14 and a length that is at least a multiple of the length of the piezoelectric substrate 14.

On one main surface of the mother substrate 13, a main surface electrode 18 is provided.
a and 18b are formed, and the parent substrate 1 is formed.
On the other main surface of No. 3, an electrode 17b to be a main surface electrode 18c is formed.

The parent substrate 13 has the electrodes 17
By applying a high DC voltage between a and 17b, polarization is caused in the thickness direction.

Then, as shown by the dashed line in FIG.
A large number of grooves 1 are formed on one main surface side of the parent substrate 13 and the electrode 17a.
6 is formed, and the parent substrate 13 and the electrodes 17 a and 17 b are cut into chips 11 used for the respective resonance elements 12. As shown in FIG. 4, the chip 11 includes a strip-shaped piezoelectric substrate 14 polarized in the thickness direction, and a groove 16 is formed at the center in the width direction on one main surface side of the piezoelectric substrate 14. Principal surface electrodes 18 a and 18 b are formed on both sides of the groove 16 on one main surface of the body substrate 14, and a main surface electrode 18 c is formed on the other main surface of the piezoelectric substrate 14.

Then, a conductive paste 20 is formed on the chip 11 from the main surface electrode 18a to the main surface electrode 18b so as to straddle the groove 16, and the resonance element 12 is formed.

Then, as shown in FIGS. 5 and 6,
The resonance element 12 is bonded to one main surface of the insulator substrate 22. In this case, main surface electrodes 18a and 1
8 c is a lead electrode 24 on one main surface of the insulator substrate 22.
a and 24b are bonded with conductive pastes 26a and 26b, respectively.

Then, the resonance element 12 is covered with a metal cap 28, and the end of the cap 28 is adhered to one main surface of the insulating substrate 22, thereby forming the piezoelectric resonator 10.

In the piezoelectric resonator 10, two main surface electrodes 18 a and 18 b of the resonance element 12 and another main surface electrode 18
c with the extraction electrode 2 on one main surface of the insulator substrate 22.
4a and another lead electrode 24b to be electrically connected to each other, since the two main surface electrodes 18a and 18b are electrically connected by the conductive paste 20, the two main surface electrodes 18a and 18b are electrically connected to each other. One main surface electrode and another main surface electrode 18c may be bonded to the extraction electrode 24a and another extraction electrode 24b, for example, using conductive pastes 26a and 26b, respectively. Therefore, a metal wire is not required to electrically connect the main surface electrodes 18a to 18c of the resonance element 12 and the extraction electrodes 24a and 24b on the insulator substrate 22, and the material of the metal wire can be reduced. A wiring device for metal wires is not required.

In the piezoelectric resonator 10, the main electrodes 18 a to 18 c of the resonance element 12 are electrically connected to the extraction electrodes 24 a and 24 b on the insulator substrate 22. Electrodes 24a and 24
Since there is no need to solder a metal wire to b,
The area of the insulator substrate 22 can be reduced.

Further, in the piezoelectric resonator 10, since the resonance element 12 is covered with the cap 28, the resonance element 1
2 is protected from the outside.

Although the groove 16 is formed at the center of the piezoelectric substrate 14 in the width direction in the embodiment of the present invention,
In the present invention, a groove may be formed in a portion of the piezoelectric substrate that is shifted from the center in the width direction.

In the above-described embodiment of the present invention, main surface electrodes 18a and 18b are electrically connected by conductive paste 20, but in the present invention, main surface electrodes 18a and 1b are connected.
8b may be electrically connected by a metal wire.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the piezoelectric resonator shown in FIG.

FIG. 3 is a perspective view showing an example of a step of manufacturing a chip used for the piezoelectric element of the piezoelectric resonator shown in FIG.

FIG. 4 is a perspective view showing a chip used for a piezoelectric element.

FIG. 5 is a perspective view showing a state where a piezoelectric element is bonded to an insulating substrate.

FIG. 6 is an illustrative view showing a state where a piezoelectric element is bonded to an insulator substrate;

FIG. 7 is an illustrative view showing one example of a conventional piezoelectric resonator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Piezoelectric resonator 12 Resonant element 14 Piezoelectric substrate 16 Groove 18a, 18b, 18c Main surface electrode 20 Conductive member 22 Insulator substrate 24a, 24b Leader electrode 26a, 26b Conductive paste 28 Cap

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H03H 9/10 H03H 9/13 H03H 9/17

Claims (2)

(57) [Claims] 1. A piezoelectric resonator having a resonance element, wherein the resonance element has a groove formed on one main surface side, and is polarized in a thickness direction. Two main surface electrodes formed on both sides of the groove, another main surface electrode formed on the other main surface of the piezoelectric substrate,
And formed at a node portion of the piezoelectric substrate,
The conductive member is a conductive member that electrically connects the two main surface electrodes.
An insulator base is formed so as to straddle the groove, and a side surface of the piezoelectric substrate faces one main surface.
Plate, formed on one main surface of the insulator substrate, the two main surfaces
One of the main surface electrodes is fixed by a conductive member.
Extraction electrode, and one of the main surfaces of the insulator substrate.
The other main surface electrode is fixed by a conductive member.
A piezoelectric resonator including an output electrode . 2. The piezoelectric resonator according to claim 1, wherein the resonance element is covered with a cap.