JPH11168349A - Electronic component and piezoelectric vibrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent influences by the scattering of a molten metal during resistance welding even in the case that an electronic component such as a piezoelectric vibrator or the like is miniaturized, and thus to improve the reliabil ity of an electronic component. SOLUTION: This is an electronic component, wherein a base 1 provided with a metallic flange 10a on a lower part peripheral edge and a cap 3 are resistance welded. On an upper surface excluding the flange area of the base 1, a flexible insulation sheet 4 with almost the same outer shape as the opening of the cap 3 is installed. The flexible insulation sheet 4 does not have to cover the entire upper surface of the base, but covering the upper part of a clearance formed between the base 1 and the cap 3 is sufficient.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component such as a piezoelectric vibrator, and more particularly to a structure for eliminating a problem at the time of hermetic sealing by resistance welding.

[0002]

2. Description of the Related Art As electronic components to be mounted are downsized, rapid downsizing is required of the electronic components, and high performance and high reliability as electronic components are also required. ing. For example, quartz resonators are widely used as frequency and time reference sources because of their excellent resonance characteristics. However, there is a demand for a product that is small in size, has small frequency fluctuations, and has stable electrical characteristics.

A conventional technique will be described with reference to FIGS. 9 and 10, taking a quartz oscillator as an example. As shown in FIG. 9, in the conventional crystal unit, two lead terminals 62 and 63 are implanted via an insulating material, and a base 6 having a flange 61 on a peripheral edge and a lead terminal protruding above the base are provided. It is composed of flat plate-like supports 64 and 65 to be welded, and a quartz vibrating plate 8 mounted flat on the support and electrically conductively bonded. Although not shown, an excitation electrode is provided on the quartz vibrating plate 8, and is electrically connected to the support by an extraction electrode following the excitation electrode. As shown in FIG. 10, a circumferential projection 61a made of metal is formed on the flange 61 of the base.
Is brought into contact with the flange 71 of the cap 7, and resistance welding is performed to perform hermetic sealing.

[0004]

In the resistance welding method, generally, as described above, a projection is provided at a joint portion, and current is concentrated at this portion to facilitate welding. However, such a projection may be scattered as molten metal B during welding, in combination with applying a pressing force to the welded portion. In the resistance welding method, since the welding is performed at the flange portion as described above, the side surfaces of the cap and the base do not come into close contact with each other, and are in a so-called gap fitting state. A part of the scattered molten metal B penetrates into the electronic component from such a gap, causing a short-circuit or the like of an electrode formed on the electronic component element, or in a vibrating component such as the above-described crystal resonator. Is attached to the quartz diaphragm,
In some cases, the vibration state is hindered, the electrical characteristics of the quartz resonator are reduced, for example, the CI value is reduced, and the reliability cannot be maintained. Such inconveniences have become apparent as electronic components have been miniaturized, resulting in a decrease in electrical performance and reliability.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. Even when electronic components such as a piezoelectric vibrator are miniaturized, the effect of scattering of molten metal at the time of resistance welding can be prevented. The purpose is to improve the reliability of parts.

[0006]

According to the present invention, there is provided an electronic component for resistance welding a base and a cap having a metal flange provided on a lower peripheral edge thereof.
A flexible insulating sheet having substantially the same outer shape as the opening of the cap is provided on the upper surface of the base excluding the flange region. Thereby, the upper part of the gap formed between the base and the cap is closed, and the molten metal which may be generated at the time of resistance welding is prevented from being scattered inside the cap having the electronic component element. The flexible insulating sheet does not need to cover the entire upper surface of the base, and may have any configuration as long as it can close the upper part of the gap formed between the base and the cap as described above.

That is, a base having a metal flange provided on a lower peripheral edge thereof, an electronic component mounted on the base via a support, and an airtight seal of the electronic component. An electronic component comprising: a metal cap having a flange that is electrically coated and has a flange that is resistance-welded to the base; and an upper surface excluding a flange region of the base has substantially the same outer shape as an opening of the cap. Wherein the flexible insulating sheet is provided.

According to the first aspect, a flexible insulating sheet having substantially the same outer shape as the opening of the cap is provided on the upper surface of the base except for the flange region, so that the side surface of the cap and the base during hermetic sealing are provided. The upper part of the gap formed on the side surface can be closed, so that molten metal which may be generated at the time of resistance welding is prevented from scattering inside the cap having the electronic component element.

According to a second aspect of the present invention, there is provided a base having at least two lead terminals penetrated and implanted in a metal shell via an insulating material, and a metal flange provided on a lower peripheral edge. A support member welded to each of the lead terminals protruding above the base, a piezoelectric vibration element mounted on the support body, and having an excitation electrode formed for electrical connection, and the piezoelectric vibration element. A piezoelectric vibrator comprising a metal cap having a flange hermetically covered with the flange of the base and a resistance welded flange, wherein an upper surface of the base excluding the flange region has substantially the same opening as the cap. A flexible insulating sheet having an outer shape is provided, and a pressing portion for fixing the flexible insulating sheet to the upper surface of the base is formed on the support. It may be. The mounting of the sheet may be performed by positioning the support on the base before the support is mounted on the base. In addition, the flexible insulating sheet can be more reliably fixed by increasing the planar area of the pressing portion within a range where there is no interference with other components.

The flexible insulating sheet may be attached by positioning the support on the base before the support is attached to the base.
In the case of the configuration as in claim 2, each lead terminal projecting from the upper portion of the base may be penetrated and attached to the sheet, and then the support may be attached.

According to the second aspect, in addition to the effect of the first aspect, a flexible insulating sheet having substantially the same outer shape as the opening of the cap is provided on the upper surface of the base except for the flange region. Since the configuration is such that the insulating sheet is fixed to the upper surface of the base by the pressing piece formed on the support, the above-described scattering of the molten metal is more reliably prevented.

According to a third aspect of the present invention, in the electronic component according to the first aspect and the piezoelectric vibrator according to the second aspect, a slit is formed in the flexible insulating sheet, and the slit is laterally inserted into a lead terminal protruding above the base. The configuration may be as follows.

According to the third aspect, in addition to the effect of the first aspect, a slit is formed in the flexible insulating sheet and the flexible insulating sheet is laterally inserted into the lead terminal protruding above the base, so that the sheet can be attached. In addition to being easy, for example, even in a configuration in which the lead terminal and the support are integrally formed, the lead terminal and the support can be easily attached by being laterally inserted.

[0014]

Next, a first embodiment of the present invention will be described with reference to the drawings, taking a quartz oscillator as an example of an electronic component. FIG. 1 is an internal sectional view showing an embodiment of the present invention, FIGS. 2 and 3 are partial sectional views showing a resistance welding method in the configuration of FIG. 1, FIG. 4 is a plan view of FIG. It is a top view showing the composition of a flexible insulating sheet.

The quartz vibrating plate 1 is formed of an AT-cut quartz vibrating plate and has a rectangular shape. Excitation electrodes 21 and 22 (the back surface 22 is not shown) and extraction electrodes 21a and 22a are provided on the front and back surfaces by means such as a vacuum deposition method. The extraction electrode 22a is a routing electrode from the back surface.

The base 1 has a long columnar shape as a whole and has a configuration in which lead terminals 11 and 12 are implanted through a base body 10 mainly composed of a metal shell, and are made of insulating glass (see FIG. 1). The lead terminals 11 and 12 are electrically independent by filling a part of the base body (not shown). A peripheral flange 10a is provided integrally with a lower peripheral portion of the base body. In addition, flange 1
A peripheral projection (projection) 10b is formed integrally with 0a.

Supports 13 and 14 made of a metal plate are joined to a part of the lead terminals projecting from the upper surface of the base in a state where they are opposed to each other. Each support has a step-like portion as a whole and has a buffer function. Then, pressing portions 13a and 14a which come into contact with a flexible insulating sheet to be described later and press against the upper surface of the base, joining portions 13b and 14b which are welded to the lead terminals continuously with these pressing portions, and a mounting portion 13c on the upper part of the step-like portion are provided. , 14c.

The metal cap 3 is in the shape of a long column with an open lower surface, and has a flange 31 at the opening corresponding to the flange 10a of the base, and is hermetically sealed by resistance welding with the base. A stop is performed.

The flexible insulating sheet 4 provided on the upper surface of the base is made of, for example, a glass fiber cloth (eg, flow glass manufactured by CHEMICAL FABRICS) coated with a heat-resistant resin material. The flexible insulating sheet 4 has substantially the same outer shape (oval shape) as the opening of the cap 3 and has cross-shaped slits 41 and 42 corresponding to the lead terminal portions of the base. I have.

In order to attach the flexible insulating sheet 4 to the base 1, the slits 41 and 42 of the flexible insulating sheet 4 are made to penetrate the protruding lead terminals, and are brought into contact with the upper surface of the base. Thereafter, the lead terminals are joined to the joining portions 13b and 14b by spot resistance welding while pressing the pressing portions 13a and 14a of the plate-like supports 13 and 14 against the base. Thus, the flexible insulating sheet 4 is positioned with its periphery slightly protruding from the upper surface of the base other than the flange.

Thereafter, as shown in FIG. 1, the quartz vibrating plate 2 is mounted on supports 13 and 14 on the base, and
14 and the extraction electrodes 11a and 12a are conductively bonded with a conductive bonding material S. Thereafter, the base is covered with a cap as shown in FIG. At this time, the outer peripheral portion of the flexible insulating sheet closes the upper part of the gap t formed between the cap and the base. Next, the hermetic sealing is completed by bringing the welding electrodes R1 and R2 into contact with both flanges, applying current to the two while applying pressure, and performing resistance welding. With the above configuration, even if molten metal B is generated during resistance welding, it does not scatter to the inside of the cap.

Note that the flexible insulating sheet is not limited to the configuration shown in the above embodiment, but may have a configuration in which slits corresponding to lead terminals of a base to be attached are formed as shown in FIG. There may be. In this case, the flexible insulating sheet is positioned between the lead terminals.

Next, a second embodiment of the present invention will be described with reference to the drawings, taking a quartz oscillator as an example. FIG. 7 is an internal sectional view showing the second embodiment, and FIG.
FIG. 4 is a plan view showing a situation where a flexible insulating sheet is attached. The same components as those in the first embodiment will be described using the same reference numerals, and a description thereof will be partially omitted.

In this embodiment, the lead terminals 51 and 52 formed on the base 5 and the supports 53 and 54 are integrally formed. That is, at the time of manufacturing the base, the lead terminals 51 and 52 integrated with the lead terminals are connected to the insulating glass 50b, 5
Ob is integrated with the base body 50 electrically independently. In such a configuration, it is difficult to penetrate and insert flexible insulating sheet 6 from above as in the above-described embodiment. Therefore, in the present embodiment, the slits 61 and 62 are formed from the side surface of the flexible insulating sheet 6 to the central portion corresponding to the lead terminal, so that the flexible insulating sheet 6 can be inserted horizontally. Lead terminal 51,
The flexible insulating sheet 6 is laterally inserted into the protruding portion (below the support portion) of the upper surface of the base 52, and then the quartz vibrating plate 2 is mounted on the support members 53 and 54 on the base. An extraction electrode (not shown) is conductively bonded with a conductive bonding material S. Then, as shown in FIG.
And hermetically sealed by resistance welding.
The flexible insulating sheet 6 may be made of a material having excellent flexibility such as Teflon or silicon.

[0025]

According to the first aspect of the present invention, a flexible insulating sheet having substantially the same outer shape as the opening of the cap is provided on the upper surface of the base excluding the flange region, so that the side surface of the cap at the time of hermetic sealing is provided. The upper part of the gap formed on the side surface of the base can be closed, thereby preventing molten metal that may be generated during resistance welding from scattering inside the cap having the electronic component element. Therefore, even when the electronic components such as the piezoelectric vibrator are downsized, the influence of the scattering of the molten metal during resistance welding can be prevented, and the reliability of the electronic components can be improved.

According to the second aspect, a flexible insulating sheet having substantially the same outer shape as the opening of the cap is provided on the upper surface of the base except for the flange region, and the flexible insulating sheet is formed on a support. Since it is configured to be fixed to the upper surface of the base by the pressing portion, the above-described scattering of the molten metal can be more reliably prevented, and the reliability of the piezoelectric vibrator can be improved.

According to the third aspect, in addition to the effect of the first aspect, a slit is formed in the flexible insulating sheet, and the flexible insulating sheet is laterally inserted into the lead terminal projecting above the base. In addition to being easy, for example, even in a configuration in which the lead terminal and the support are integrally formed, the lead terminal and the support can be easily attached by being laterally inserted.

[Brief description of the drawings]

FIG. 1 is an internal sectional view showing a first embodiment according to the present invention.

FIG. 2 is a sectional view showing a resistance welding method in the configuration of FIG.

FIG. 3 is a sectional view showing a resistance welding method in the configuration of FIG. 1;

FIG. 4 is a plan view of FIG. 1 before covering a cap;

FIG. 5 is a plan view showing a configuration of a flexible insulating sheet.

FIG. 6 is a plan view showing another configuration example of the flexible insulating sheet.

FIG. 7 is an internal cross-sectional view showing a second embodiment according to the present invention.

FIG. 8 is a plan view showing a situation where a flexible insulating sheet is attached in the second embodiment.

FIG. 9 is an internal sectional view showing a conventional example.

FIG. 10 is an internal sectional view showing a state before resistance welding of a conventional example.

[Explanation of symbols]

 1, 5, 6 Base 10a, 50a, 31, 51, 61 Flange 13, 14, 53, 54, 64, 65 Support 13a, 14a Pressing section 2, 8 Quartz diaphragm 3, 7 Cap 4, 43, 6 Flexible Insulating sheet 41, 42, 44, 61, 62 Slit

Claims (3)

[Claims] 1. A base having a metal flange provided on a lower peripheral edge, an electronic component mounted on the base via a support, and an airtight covering of the electronic component,
An electronic component comprising a flange of the base and a metal cap having a flange that is resistance-welded, wherein a flexible insulating sheet having an outer shape substantially the same as the opening of the cap is provided on an upper surface excluding a flange region of the base. An electronic component characterized by being installed. 2. A base having at least two lead terminals penetrated and implanted in a metal shell via an insulating material, and a base formed by providing a metal flange on a lower peripheral edge, and protruding above the base. A support that is welded to each lead terminal, a piezoelectric vibrating element mounted on the support and formed with an excitation electrode to be electrically connected, and an airtight covering of the piezoelectric vibrating element; And a metal cap having a flange to be resistance-welded, wherein a flexible insulating sheet having substantially the same outer shape as the opening of the cap is provided on an upper surface of the base excluding the flange region. And a pressing portion for fixing the flexible insulating sheet to the upper surface of the base is formed on the support. Child. 3. The electronic component according to claim 1, wherein a slit is formed in the flexible insulating sheet, and the slit is laterally inserted into a lead terminal projecting above the base.