JP4843424B2 - Glass sealing cover for crystal resonator and method for manufacturing crystal resonator using the same - Google Patents

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.

(First solving means)
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. the a, in the glass sealing cover for the crystal oscillator for sealing the open end face of the container body has a concave that crystal blank is accommodated, at least the low profile area of the sealing glass is inside of the cover base It is set as the structure which protruded.
(Second solution)
Further, according to the present invention, as shown in the claims (Claim 4), a crystal piece, a container main body having a concave portion for accommodating the crystal piece, and an opening end surface of the container main body are joined by sealing glass. And a cover matrix for hermetically enclosing the quartz crystal piece, wherein the sealing glass is welded to the cover matrix to circulate around the cover matrix and the outer periphery of the cover matrix. A glass sealing cover having a low profile area with a small height to form a concave vent hole, and at least the low profile area projecting inward of the cover matrix. A glass sealing cover manufacturing step, a mounting step of mounting the glass sealing cover with the sealing glass facing the opening end surface of the container body in which the crystal piece is accommodated in the recess, and the sealing Glass By hot melting a structure having a bonding step of bonding the container body and the cover base.

(Effects of the first solving means)
In the case of the glass sealing cover of the first solving means, the low-profile region that forms the vent hole protrudes to the inside of the cover base, so that the width in the low-profile region becomes large and the sealing glass at the vent hole Increase the amount of. 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 of first solving means)
According to a second aspect of the present invention, in the first aspect, the sealing glass having a height higher than the low-back region at least one end side of the low-back region together with the low-back region protrudes inward of the cover matrix. To do. 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, the sealing glass having a height higher than that of the low-back area on both ends of the low-back area together with the low-back area protrudes inward of the cover matrix . 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.

(Effects of the second solving means)
  If it is a manufacturing method of the 2nd solution means, in a glass sealing cover preparation process, since the low back area which forms a vent hole will weld sealing glass so that it may protrude inside a cover mother body, Increases the amount of sealing glass in the vent hole. Therefore, in the joining process, the sealing glass having a large height on both ends of the low-back area flows into the low-back area and enters between the opening end face of the container body by capillary action, so the thickness of the low-back area This prevents the deterioration of the wettability with respect to the opening end surface of the container main body caused by the decrease in the thickness of the container main body.

(Embodiment section of second solving means)
  In Claim 5 of this invention, in the said glass sealing cover preparation process, the said sealing glass is welded so that the said low back area may protrude inside from the inner periphery of the opening end surface of the said container main body after the said installation process. It is set as the structure made to do. 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.

  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).

  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. in glass sealing cover for the crystal oscillator for sealing the opening end face, at least the low profile area of the sealing glass is glass sealing for the crystal oscillator, characterized in that inwardly projecting of the cover base cover. 2. The glass seal for a crystal resonator according to claim 1, wherein the sealing glass having a height higher than that of the low-back region and at least one end of the low-back region is projected inward of the cover base. Stop cover. 2. The glass seal for a crystal resonator according to claim 1, wherein the sealing glass having a height higher than that of the low-back area on both ends of the low-back area together with the low-back area protrudes inward of the cover matrix. cover.   A method of manufacturing a crystal resonator, comprising: a crystal piece; a container main body having a concave portion that accommodates the crystal piece; and a cover base that is bonded to an opening end surface of the container main body by a sealing glass and hermetically encloses the crystal piece. In
  The sealing glass is welded to the cover base, and the cover base and the cover base have a low profile with a small height that circulates around the outer periphery of the cover base and forms a concave vent hole. The low-back region has a glass sealing cover manufacturing step for preparing a glass sealing cover having the sealing glass protruding inward of the cover matrix,
  A placing step of placing the glass sealing cover with the sealing glass facing the opening end surface of the container body in which the crystal piece is accommodated in the recess;
  A method of manufacturing a crystal resonator, comprising: a joining step of joining the cover base body and the container body by heating and melting the sealing glass.   In the said glass sealing cover preparation process, the said sealing glass is welded so that the said low back area may protrude inside from the inner periphery of the opening end surface of the said container main body after the said mounting process. A method for manufacturing a crystal unit.