JP2008066885A - Glass sealing cover for crystal vibrator, and crystal vibrator for surface mounting using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a glass sealing cover capable of securing a joint to a container body to improve productivity, and to provide a surface mounted crystal vibrator capable of preventing deposition of sealing glass using the cover and maintaining oscillation characteristic in a proper condition. <P>SOLUTION: The glass sealing cover 3 for a crystal vibrator comprises a revolving sealing glass 9 on the perimeter of a cover parent body 3a. The sealing glass 9 comprises a low height area 11 with small thickness for forming a vent hole 10. The glass sealing cover 3 seals the aperture end side of a concave container body where a crystal piece is held. Wherein, at least the low height area 11 of the sealing glass 9 is configured to be projected into inside of the cover parent 3a. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention has a technical field of a glass sealing cover for a crystal unit and a surface mounting crystal unit (hereinafter referred to as a surface mounting unit) using the same, and in particular, the glass sealing is ensured to increase productivity. It relates to an elevated glass sealing cover.

(Background of the Invention)
Since the surface-mounted resonator is small and light, it is built in as a reference source for frequency and time, especially in portable devices. One of these is a surface-mounted vibrator in which a crystal piece is hermetically sealed in a container body using a glass sealing cover.

(Example of conventional technology)
3 and 4 are diagrams for explaining one conventional example. FIG. 3 (a) is a cross-sectional view of a surface mount vibrator, FIG. 3 (b) is a plan view excluding the cover, and FIG. Is a plan view of a crystal piece, FIG. 4 (a) is a plan view of one main surface of a glass sealing cover, FIG. 4 (b) is a partial cross-sectional view along A-A, and FIG. It is the side view of the short side direction made into the partial cross section at the time of joining.

  The surface-mounted vibrator accommodates a crystal piece 2 in a container body 1 having a rectangular planar outer shape, and a glass sealing cover 3 having the same rectangular shape is joined to hermetically enclose the crystal piece 2. The container body 1 is made of a laminated ceramic having a concave shape, and has a crystal terminal 4 on the inner bottom surface and a mounting terminal 5 for surface mounting on the outer bottom surface. The crystal terminal 4 is electrically connected to the mounting terminal 5 through the laminated surface and the through hole 5a.

  The crystal piece 2 has excitation electrodes 6 on both main surfaces, and for example, extraction electrodes 7 extend on both sides of one end. Then, both ends of the extended end portion of the extraction electrode 7 are fixed to the crystal terminal 4 on the inner bottom surface by the conductive adhesive 8. In addition, since the crystal piece 2 is easier to design as the plate surface area is larger, the gap between the container 2 and the inner periphery of the container body 1 is smaller as the size is reduced.

  The glass sealing cover 3 is made smaller than the planar outer shape of the container body 1 by using, for example, ceramic as a cover base. Thereby, jumping out from the outer periphery of the container main body 1 is prevented. And it has the sealing glass 9 in the outer periphery which the one main surface of a cover base | substrate rotates. The sealing glass 9 is provided by welding and is a low melting glass having a melting point temperature of about 280 to 500 ° C.

  The inner periphery of the sealing glass 9 coincides with the inner periphery of the container body, and the so-called through path is lengthened to improve the airtightness. And it has the vent hole 10 which opposes a pair of short side which opposes, for example. The gas vent hole 10 is formed in a concave shape by providing a low profile region 11 having a small height in a part of the sealing glass 9.

  Then, the outer periphery of the glass sealing cover 3 is brought into contact with the opening end surface of the container main body 1, and the sealing glass 9 is heated and melted. Thereby, the opening end surface of the container main body 1 is sealed, and the crystal piece 2 is hermetically sealed. Heating and melting is performed, for example, in an N (nitrogen) gas atmosphere, and N gas is sealed in the container. Good aging characteristics are maintained by the inert gas of N gas.

  In this case, when the sealing glass 9 does not have the gas vent hole 10, the glass sealing cover 3 is entirely bonded to the container body 1 and closed at the initial stage of glass melting (at low temperature). And if temperature rises further, the internal pressure of a container will increase by expansion of gas (N). For this reason, as shown in FIG. 5, the glass sealing cover 3 is lifted to cause “the same figure (a)”, and the height dimension is increased or an inclined surface is generated. Alternatively, the sealing glass 9 is blown out, and (b) in FIG.

  On the other hand, when the sealing glass 9 has the gas vent hole 10, even if the internal pressure of the container is increased, the gas is appropriately released, and the sealing glass 9 is covered as shown in FIG. The inside of the container body 1 and the inner surface of the container body 1 are wetted, and the glass sealing cover 3 is normally sealed in parallel.

(Problems of conventional technology)
However, in the surface mount vibrator having the above-described configuration, the sealing glass 9 is provided with the low-profile region 11 and the gas vent hole 10 is formed. Therefore, the thickness of the sealing glass 9 in the low-profile region 11 is necessarily reduced. . For this reason, at the time of heating and melting, the wettability between the sealing glass 9 in the gas vent hole 10 (low profile region 11) and the opening end surface of the container body 1 is poor and the bonding becomes sparse. Or there existed a problem which produced the blow-off from the gas vent hole 10, raise | generates an airtight defect, and reduces productivity.

  From this, it was considered that the thickness of the sealing glass 9 was increased as a whole and the wettability in the low-back region 11 was improved. However, in this case, the amount of the sealing glass 9 increases, and when it is welded to the outer periphery of the cover base or when it is joined to the container body 1, it aggregates at the four corners of the cover having a large area. For this reason, the sealing glass 9 flows into the container main body 1 from the four corners. Then, there is a problem that it adheres to the crystal piece 2 to deteriorate the vibration characteristics and becomes a waste product as a characteristic defect.

  As the planar outer shape of the container body 1 becomes smaller (for example, 3.2 × 2.5 mm), the frame width of the container body 1 becomes narrower (for example, about 0.3 mm), and the control of the vent hole 10 of the sealing glass 9 becomes difficult. become. Moreover, since the inner product of the container main body 1 is reduced and the gap between the crystal piece 2 and the inner periphery is also reduced, the problem due to the inflow of the sealing glass 9 is increased. For example, the external shape of the crystal piece 2 is about 2.0 × 1.4 mm, and the gap with the inner periphery is about 0.25 mm or less.

(Object of invention)
The present invention provides a glass sealing cover that improves the productivity by ensuring bonding to a container body, and a surface-mounted vibrator that uses this to prevent adhesion of sealing glass and maintain good vibration characteristics. For the purpose.

  As shown in the claims (Claim 1), the present invention has a sealing glass that circulates on the outer periphery of the cover base body, and the sealing glass has a low-profile low-profile region that forms a vent hole. And a glass sealing cover for a crystal resonator that seals the opening end surface of the concave container body in which the crystal piece is accommodated, wherein at least the low-back region of the sealing glass is inward of the cover matrix. Protruding configuration.

  With such a configuration, the low-profile region that forms the vent hole protrudes to the inside of the cover base, so the width in the low-profile region increases and the amount of sealing glass in the vent hole increases. . In this case, the width (protrusion length) is set so as to compensate for the decrease caused by reducing the height of the low-profile area. Accordingly, when the container body is sealed, the glass amount is about the same as that when the container body has a uniform height without a vent hole, so that the wettability with respect to the opening end surface of the container body is maintained well.

  And the height of the sealing glass excluding the low profile is the same as the conventional one, and it does not increase the amount of the sealing glass as a whole, so the sealing glass aggregates in the four corners and enters the container body. Prevent inflow. Therefore, it is possible to improve the productivity by reliably joining the container body.

(Embodiment section)
According to a second aspect of the present invention, in the first aspect, the cover is provided with a gas vent hole including a sealing glass having a height higher than that of the low-back region and at least one end of the low-back region. Projects inward of the mother. According to this, since the sealing glass whose height at least on one end side is larger than the low profile region also protrudes, the amount of the sealing glass in the gas vent hole is increased. Moreover, it flows in from the one where the height of one end side is larger to the lower one, and the gas vent hole is easily closed.

  In the third aspect of the present invention, in the first aspect of the present invention, in the first aspect, the vent hole including the sealing glass having a height higher than that of the low-back area on both ends of the low-back area as well as the low-back area is provided in the cover base body. Protrudes towards. According to this, since the sealing glass with a large height on both end sides of the low profile region protrudes, the amount of the sealing glass in the gas vent hole is further increased. Moreover, since it flows in from the one where the height of both end sides is large to the one where it is low, it is easier to close the vent hole.

  In the fourth aspect of the present invention, in the first, second, or third aspect, the low-profile region projects inward from the inner periphery of the container body. According to this, since the sealing glass excluding the low-profile region of the vent hole can be formed up to the inner periphery of the container body, a so-called through path can be lengthened to ensure airtightness.

(Application example)
In the fifth aspect of the present invention, the opening end face of the container body is sealed using the glass sealing cover for the quartz crystal resonator according to the first aspect. Thereby, since the sealing glass does not adhere to the crystal piece, the vibration characteristics of the surface-mount vibrator are favorably maintained.

  FIG. 1 is a plan view of one main surface of a glass sealing cover for explaining an embodiment of the present invention, and FIG. In addition, the same number is attached | subjected to the same part as a prior art example, and the description is simplified or abbreviate | omitted.

  As described above, the glass sealing cover 3 is made of ceramic as the cover body, and the sealing glass 9 that circulates around the outer periphery of one main surface is provided by welding. Also here, the inner periphery of the sealing glass 9 and the container main body 1 coincide, and the outer periphery is made smaller than the container main body. And it has the concave-shaped degassing hole 10 in which the low-profile area 11 with small height was provided in the center part of the short side which the glass sealing cover 3 made into the rectangular shape opposes.

  In this embodiment, the width of the gas vent hole portion including the low-profile region 11 forming the gas vent hole 10 of the sealing glass 9 and the sealing glass 9 having a large height on both ends thereof is increased, and the container body 1 is projected inward from the inner periphery of the frame. Here, it is made to protrude to the extent which becomes more than the quantity of the sealing glass 9 reduced by the low profile region 11. And as above-mentioned, the outer periphery of the glass sealing cover 3 contacts and positions the opening end surface of the container main body 1, and the sealing glass 9 is heat-melted in N gas atmosphere. Thereby, the crystal piece 2 in the container body 1 is hermetically sealed (see the previous FIG. 3).

  With such a configuration, when the sealing glass 9 of the glass sealing cover 3 is melted, the high-pressure gas (N) by heating is appropriately discharged through the gas vent hole 10 as described above, and is normally sealed. Previous FIG. 5 (c) ". And since the low vent region 11 and the gas vent holes on both ends thereof are projected, the amount of the sealing glass 9 in the gas vent holes increases.

  In this case, the sealing glass 9 on both end sides having a large height flows into the low-profile region 11 and enters between the opening end surface of the container body 1 by capillary action. Therefore, the deterioration of the wettability with respect to the opening end surface of the container main body 1 caused by the small thickness of the low-profile region 11 is prevented and improved, and the bonding to the container main body 1 is made dense. And since a junction is dense, there is no blowing from the degassing hole 10, and confidentiality is ensured.

  And since only the gas vent hole part is protruded and the periphery of the four corners is the same as the conventional one, there is no aggregation of the sealing glass 9 at the time of melting, and the inflow into the container body 1 is prevented. Therefore, since the sealing glass 9 does not adhere to the crystal piece 2, the vibration characteristics are maintained well.

(Other matters)
In the above embodiment, the low-profile region 11 and the gas vent holes at both ends thereof are protruded. For example, even in the low-profile region 11 and only one end thereof, “FIG. 2 (a)” or the low profile region Even if only 11 is provided, the same effect as in FIG. Further, although the gas vent hole 10 is provided in the opposing short side direction, it is needless to say that it may be in the long side direction or the like.

  In addition, although the sealing is performed in a nitrogen atmosphere, for example, even in the vacuum chamber, since the vacuum is not complete, for example, in the initial state in which the cover is in contact with the container body, the internal pressure increases, Since the blowout is generated, it is useful even in the case of vacuum sealing.

The top view of the one main surface of the glass sealing cover explaining one Embodiment of this invention, the figure (b) is AA partial sectional drawing. It is a figure explaining other embodiment of this invention, and the same figure (ab) is a top view of one main surface of a glass sealing cover. FIG. 3A is a cross-sectional view of a surface-mounted vibrator, FIG. 3B is a plan view excluding the cover, and FIG. 3C is a plan view of a crystal piece. It is a figure explaining a prior art example, The figure (a) The top view of one main surface of a glass sealing cover, The figure (b) is AA partial sectional drawing, The figure (c) is the joining to a container main body. It is the side view of the short side direction made into the partial cross section at the time. FIG. 4B is a diagram for explaining a conventional example. FIG. 4A is an example of a defective product (partial sectional view), and FIG. 3C is an example of a non-defective product (partial sectional view).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Container body, 2 Crystal piece, 3 Glass sealing cover, 4 Crystal terminal, 5 Mounting electrode, 6 Excitation electrode, 7 Extraction electrode, 8 Conductive adhesive, 9 Sealing glass, 10 Gas vent hole, 11 Low profile ,

Claims (5)

  A sealing glass that wraps around the outer periphery of the cover base, and the sealing glass has a low profile with a small height that forms a concave vent hole, and is a concave container body that accommodates a crystal piece. A glass sealing cover for a crystal resonator for sealing an opening end face, wherein at least a low-back region of the sealing glass protrudes inward of the base of the cover. .   2. The quartz crystal according to claim 1, wherein a gas vent hole including a sealing glass having a height higher than that of the low-back area and at least one end side of the low-back area together with the low-back area protrudes inward of the cover matrix. Glass sealing cover for vibrators.   2. The crystal vibration according to claim 1, wherein a gas vent hole including a sealing glass having a height higher than that of the low-profile region on both ends of the low-profile region together with the low-profile region is projected inward of the cover matrix. Glass sealing cover for child.   4. The glass sealing cover for a crystal resonator according to claim 1, 2, or 3, wherein the low-profile region projects inward from the inner periphery of the container body.   A surface-mount crystal resonator formed by sealing the opening end surface of the container body using the glass seal cover for crystal resonator according to claim 1, 2, 3, or 4.