JPH06216692A - Piezoelectric resonance component - Google Patents

Abstract

PURPOSE:To provide a piezoelectric resonance component with good resonance characteristics and the high connection reliability of a drawer electrode and an external electrode by suppressing adhesive from flowing into vibration spaces or swelling out to an outside from the bonding part of holding substrates and a piezoelectric element. CONSTITUTION:A groove 11 where the excessive adhesive 8 is to be collected is formed on the bonding surfaces of the holding substrates 6 and the piezoelectric element 4 of the piezoelectric resonance component provided with the piezoelectric element 4, the holding substrates 6 stuck to both side faces of the piezoelectric element 4 by the adhesive 8 for holding the piezoelectric element 4 so as to enable vibration for which recessed parts 5 for forming the vibration spaces are formed at positions opposed to the side faces of the piezoelectric element 4 and sealing substrates 7 for holding the piezoelectric element 4 and the holding substrates 6 there between from both upper and lower main surface sides.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric resonance component, and more particularly to a piezoelectric resonance component characterized by the structure of a bonding portion of a holding substrate for holding a piezoelectric element in a vibrating manner.

[0002]

2. Description of the Related Art In recent years, as electronic devices and electric devices have been miniaturized, there has been an increasing demand for miniaturization of piezoelectric resonance components used therein. FIG. 4 is an exploded perspective view showing an example of a thin piezoelectric resonance component utilizing a thickness shear vibration mode developed to meet such a demand.

In this piezoelectric resonance component, as shown in FIG. 4, vibrating electrodes 22 are provided on the side surfaces of the piezoelectric substrate 21 which face each other on the longitudinal sides, and the vibrating electrodes 22 are different from each other. A thickness-shear vibration mode piezoelectric element 24 formed by pulling out the extraction electrode 23 at the end portion on the side is used.

The vibrating electrode 22 of the piezoelectric element 24
The vibrating electrodes 22 of the piezoelectric element 24 are provided on both side surfaces on which the
A holding substrate 26 made of an insulating material, in which a concave portion 25 is formed to secure a vibration space between the holding element 26 and the surface on which the piezoelectric element 24 is provided, is adhered by an adhesive 28, and the piezoelectric element 24 is fixed by the holding substrate 26. It is held so that it can vibrate.

Further, the piezoelectric element 24 and the holding substrate 26
Is sealed by adhering a sealing substrate 27 made of an insulating material such as resin from above and below both main surfaces with an adhesive 30. Since the adhesive 30 also functions as a spacer and forms a gap between the piezoelectric element 24 and the sealing substrate 27, the sealing substrate 27 does not hinder the vibration of the piezoelectric element 24. In addition, external electrodes 29 that are electrically connected to the extraction electrodes 23 are formed on both end surfaces of the laminated body obtained by sealing the piezoelectric element 24 and the holding substrate 26 with the sealing substrate 27.

[0006]

However, in the above-mentioned conventional piezoelectric resonance component, as shown in FIG.
When the holding substrate 26 is adhered to both side surfaces of the adhesive 4, the adhesive 28
However, there is a case in which the spillage flows out from the bonding portion (between the bonding surfaces), flows into the vibration electrode 22 of the piezoelectric element 24 in the vibration space (recessed portion) 25, or spills outside from the bonding portion. When the piezoelectric element 24 enters the vibrating space (recess) 25, the original vibration of the piezoelectric element 24 is disturbed, resulting in poor electrical characteristics (resonance characteristics). There is a problem that the connection between 23 and the external electrode 29 becomes insufficient.

The present invention solves the above problems, and when the holding substrate is adhered to the piezoelectric element by an adhesive, the adhesive flows into the vibrating space or sticks out from the adhered portion. , The resonance characteristics are good,
Moreover, it is an object of the present invention to provide a piezoelectric resonance component having a highly reliable connection between the extraction electrode and the external electrode.

[0008]

In order to achieve the above object, in a piezoelectric resonance component of the present invention, vibrating electrodes are provided on surfaces of a piezoelectric substrate that face each other, and the piezoelectric substrate is different from each vibrating electrode. A piezoelectric element of thickness-shear vibration mode in which a lead-out electrode is drawn out to the end on the side, and a side surface of the piezoelectric element, which is adhered to both side surfaces of the piezoelectric element with an adhesive so as to vibrate the piezoelectric element. A piezoelectric resonance component comprising: a holding substrate having a concave portion for forming a vibration space formed at a position where the vibration element is formed; and a sealing substrate for sandwiching and sealing the piezoelectric element and the holding substrate from both upper and lower main surface sides thereof. In the above, in the above-mentioned holding substrate, a groove for accumulating an excessive amount of adhesive is formed on a surface of the holding substrate which is bonded to the side surface of the piezoelectric element.

[0009]

A groove is formed on the surface of the holding substrate that holds the piezoelectric element so that it can vibrate, and a groove is formed on the surface of the holding element that adheres to the side surface of the piezoelectric element. At least a part of the excess portion of this is accumulated in this groove. Therefore, excess adhesive may flow into the vibrating space,
It is possible to reduce the degree of protrusion from the adhesive to the outside, and to obtain a piezoelectric resonance component that has better resonance characteristics than conventional piezoelectric resonance components and that has a highly reliable connection between the extraction electrode and the external electrode. Will be able to.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view showing a piezoelectric resonance component according to an embodiment of the present invention, and FIG. 2 is a vibration element that vibrates the piezoelectric element by attaching holding substrates to both sides of the piezoelectric element that constitutes the piezoelectric resonance component. It is a top view which shows the state hold | maintained possible.

As shown in FIGS. 1 and 2, in the piezoelectric resonance component of this embodiment, the vibrating electrodes 2 are arranged on the side surfaces of the piezoelectric substrate (PZT substrate) 1 on the longitudinal sides facing each other and each vibration is performed. A thickness-shear vibration mode piezoelectric element 4 formed by pulling out a lead-out electrode 3 from the electrode 2 to an end portion on a different side of the piezoelectric substrate 1 is used.

Further, on both side surfaces of the piezoelectric element 4 on which the vibrating electrode 2 is arranged, a concave portion 5 is provided for securing a vibrating space between the piezoelectric element 4 and the surface on which the vibrating electrode 2 is arranged. A holding substrate 6 made of an insulating material in which is formed is disposed by an adhesive, and the piezoelectric element 4 is vibratably held by the holding substrate 6. A groove (recess) 11 extending from the upper surface side to the lower surface side is formed on the surface of the holding substrate 6 that is bonded to the side surface of the piezoelectric element 4.

The piezoelectric element 4 and the holding substrate 6 are sealed by adhering the sealing substrate 7 with the adhesive 10 from both upper and lower main surface sides. Since the adhesive 10 also functions as a spacer and forms a gap between the piezoelectric element 4 and the sealing substrate 7, the sealing substrate 7 does not hinder the vibration of the piezoelectric element 4.

External electrodes 9 that are electrically connected to the extraction electrodes 3 are formed on both end surfaces of the laminated body obtained by sealing the piezoelectric element 4 and the holding substrate 6 with the sealing substrate 7.

In the piezoelectric resonance component of this embodiment, as described above, the holding substrate 6 in which the grooves (recesses) 11 are provided on the adhesive surfaces of both sides of the piezoelectric element 4 on which the vibrating electrodes 2 are arranged. Since they are adhered by the adhesive 8,
Excessive part of the adhesive 8 existing between the side surface of the piezoelectric element 4 and the bonding surface of the holding substrate 6 collects in the groove (recess) 11. Therefore, the extent to which the adhesive 8 flows into the vibrating space (recess) 5 or protrudes from the adhesive to the outside is smaller than that of the conventional piezoelectric resonance component described above.

As a result, the electric characteristics (resonance characteristics) are deteriorated due to the flow of the adhesive 8 onto the vibrating electrode 2 of the piezoelectric element 4, and the lead electrode 3 and the external electrode are caused by the protrusion of the adhesive 8 from the bonded portion to the outside. It is possible to obtain a piezoelectric resonance component which suppresses the occurrence of a connection failure between 9 and has good resonance characteristics and high connection reliability between the extraction electrode and the external electrode.

In the above embodiment, the case where one groove (concave portion) 11 is formed substantially at the center of each bonding surface of the holding substrate 6 has been described. However, in the piezoelectric resonance component of the present invention, the groove (concave portion) is formed. ) There are no particular restrictions on the specific shape, number of arrangements, arrangement positions, etc. of 11, for example, it is possible to form a plurality of grooves (recesses) on each bonding surface, as shown in FIG. , Forming two grooves (recesses) 11 on each bonding surface,
By arranging the two grooves (recesses) 11 at positions on both ends of each bonding surface, it is more effective that the adhesive 8 flows into the vibrating space (recess) 5 or protrudes to the outside. Can be suppressed.

In the above embodiments, the case where the piezoelectric element having the vibrating electrodes provided on both side surfaces of the piezoelectric substrate is used has been described, but in the present invention, the vibrating electrodes are arranged on the upper surface and the lower surface of the piezoelectric substrate. It can also be applied to a piezoelectric resonance component that uses a provided piezoelectric element.

Further, the piezoelectric resonance component of the present invention is not limited to the above embodiment in other respects, and relates to the shape of the piezoelectric element, the electrode pattern, the specific shape of the holding substrate or the sealing substrate, and the like. Various applications and modifications can be made within the scope of the invention.

[0020]

As described above, in the piezoelectric resonance component of the present invention, since the holding substrate in which the groove for accumulating an excessive amount of adhesive is formed on the bonding surface with the piezoelectric element, the adhesive is used in the vibration space. It is possible to prevent the liquid from flowing into the (concave portion) or protruding from the adhesive portion to the outside.

Therefore, the electrical characteristics (resonance characteristics) are deteriorated due to the adhesive flowing into the vibrating portion of the piezoelectric element, and the defective connection between the extraction electrode and the external electrode is caused by the protrusion of the adhesive from the adhesive portion to the outside. It is possible to obtain a piezoelectric resonance component having excellent resonance characteristics and having high connection reliability between the extraction electrode and the external electrode.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a piezoelectric resonance component according to an embodiment of the present invention.

FIG. 2 is a plan view showing a state in which a holding substrate is bonded to both side surfaces of a piezoelectric element that constitutes a piezoelectric resonance component according to an embodiment of the present invention, and the piezoelectric element is vibratably held.

FIG. 3 is a diagram showing a main part of a piezoelectric resonance component according to another embodiment of the present invention, a plan view showing a state in which holding substrates are adhered to both side surfaces of the piezoelectric element and the piezoelectric element is vibratably held. It is a figure.

FIG. 4 is an exploded perspective view showing a conventional piezoelectric resonance component.

FIG. 5 is a plan view showing a state in which a holding substrate is adhered to both side surfaces of a piezoelectric element that constitutes a conventional piezoelectric resonance component, and the piezoelectric element is oscillatably held.

[Explanation of symbols]

 1 Piezoelectric Substrate 2 Vibration Electrode 3 Extraction Electrode 4 Piezoelectric Element 5 Recess (Vibration Space) 6 Holding Substrate 7 Sealing Substrate 8 Adhesive 9 External Electrode 11 Groove (Recess)

Claims (1)

[Claims] 1. A thickness-shear vibration mode piezoelectric element in which vibrating electrodes are provided on mutually opposing surfaces of a piezoelectric substrate, and lead-out electrodes are drawn from the respective vibrating electrodes to end portions on different sides of the piezoelectric substrate. A holding substrate, which is adhered to both side surfaces of the piezoelectric element with an adhesive to hold the piezoelectric element in a vibrating manner, and in which a recess for forming a vibration space is formed at a position facing the side surface of the piezoelectric element, and the piezoelectric element. And a sealing substrate that holds and holds the holding substrate from both upper and lower main surface sides thereof, wherein the holding substrate has an excessive bonding surface with the side surface of the piezoelectric element. A piezoelectric resonance component having a groove in which an adhesive agent is formed.