JP2001127576A - Structure for package for piezoelectric vibrator and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a means that thins the thickness of a base of a vibrator package for cold press bonding or resistance welding. SOLUTION: Deep drawing is applied to a metallic plate to obtain a package, a flange for cold press bonding is formed to its opening, holes are made to a thick part of the bottom of the package and lead terminals are air-tightly penetrated through the holes by using a glass material to obtain the base.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a package structure for a piezoelectric vibrator, and more particularly to a piezoelectric vibrator having a reduced height by preventing distortion of a lead terminal portion applied to an insulating glass material during sealing. For package structure.

[0002]

2. Description of the Related Art A package for a piezoelectric vibrator is necessary for a contained piezoelectric vibrating element to cut off the influence of the surrounding environment. For example, the stability and frequency of about 10 ^-6 required for a crystal vibrator are required. The interior is evacuated to satisfy the secular change or the like, or is filled with an inert gas and hermetically sealed. FIG. 5 is a cross-sectional view showing an example of the structure of a conventional package in which a piezoelectric vibrating element Y is mounted on supports S1 and S2. The package comprises a base portion B and a metal case K. The base portion B is provided with a plurality of holes in a metal substrate 51 processed into a shallow dish shape, and an insulating glass is provided to allow the lead terminals 53, 53 to pass through the holes in an airtight manner. The material 52 is filled in a dish-shaped portion of the base. On the other hand, the metal case K is formed by deep drawing a metal plate and forming a flange at the opening. Supports S1 and S2 are fixed by welding to the tips of the lead terminals 53 of the base portion B. Then, the piezoelectric vibrating element Y is placed on the flat portions of the arms of the supports S1 and S2, and both are conductively fixed by the conductive material 54. Further, the flange 55 of the base portion B and the flange 56 of the metal case K are pressed and fixed by means of cold press welding (cold welding) or resistance welding, and hermetically sealed to complete the piezoelectric vibrator. The support S has various shapes and is generally resistant to vibration and impact, and generally has a shape that does not impair the original Q value of the piezoelectric vibrator.

FIG. 6 is a sectional view showing an example of another conventional package structure. The base portion B has a plurality of external terminals 62 on the outer bottom of the ceramic substrate 61, and has a plurality of lead terminals (not shown) which are in air-tight communication with the external terminals 62 on the inner upper surface. Further, the side surfaces of the ceramic substrate 61 are metallized, and a flange is provided in one opening.
It has a structure in which the inner surface of a short metal cylinder formed with 63 and the metallized surface are silver brazed. Supports S are provided on the lead terminals (not shown) on the inner upper surface of the ceramic substrate 61.
1, S2 is welded, the piezoelectric vibrating element Y is placed on the flat part of the arm, and both are conductively fixed with a conductive material.
Further, the flange 64 of the metal case K and the flange 63 of the base B are cold-welded or resistance-welded using a means such as
The piezoelectric vibrator is hermetically sealed.

As is well known, not only the supports as shown in FIGS. 5 and 6 but also, for example, as shown in FIG. 7, one support is formed as one tongue-shaped piece. FIG. 2A is a perspective view showing a structure in which supports S1, S2, S3, and S4 are welded to lead terminals T1, T2, T3, and T4 of a base portion B, and FIG. (C) is a side view of the support alone.

[0005]

However, in the structure of the conventional base shown in FIG. 5 or 6, pressure is applied to the flange 55 or 63 of the base portion B at the time of cold welding or resistance welding, and the vicinity thereof is There was a risk of cracks in the glass 52 or the ceramic 61. To avoid this, it is conceivable to increase the thickness of the glass or ceramic and increase the thickness of the flange, but there is a problem that the thicker wall prevents the reduction in height of the piezoelectric vibrator, which is a requirement from users. Was. In the package base shown in FIG. 7, when the support S and the lead terminal T are welded, complicated work such as positioning and welding the small supports S one by one is repeated. Even if a jig is used to position the support and the terminal on the base, the distance between the supports is not always constant, and the piezoelectric vibrating element is mounted when the piezoelectric vibrating element is mounted. If there is no margin between the substrate and the end of the support S, a sufficient amount of conductive adhesive cannot be applied, and there is a problem in that the conductive adhesive is easily peeled off due to vibration, impact, and the like, thereby deteriorating electrical characteristics. The present invention has been made in order to solve the above-mentioned problem, and to provide a package structure in which distortion generated at the time of sealing the package does not directly affect the glass or ceramic of the base portion. The first object is to provide a manufacturing method for facilitating the installation of the support.

[0006]

According to a first aspect of the present invention, there is provided a piezoelectric vibrator package having a structure and a manufacturing method according to the present invention. Forming a flange, making a plurality of holes in the bottom of the metal container, making the plurality of lead terminals airtightly penetrate using a glass material in the holes, and joining the flange and the peripheral edge of the plate-shaped metal lid. Thus, the piezoelectric vibrator package can be hermetically sealed. The invention according to claim 2 is characterized in that the other opening of the metal cylinder having a flange formed in one opening is closed with a ceramic substrate, and the flange is joined to the peripheral edge of a plate-shaped metal lid. This is the structure of the package for the piezoelectric vibrator. The invention according to claim 3 is a method for mounting a support member on a lead terminal provided on a base of a package, wherein a metal plate having a plurality of tongue-like pieces is formed integrally from a center radially, After fixing the vicinity of the base of each tongue piece of the metal plate to the lead terminal by welding,
A method for manufacturing a package for a piezoelectric vibrator, wherein a central portion of the metal plate is cut from each tongue-shaped piece and removed.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the drawings. FIG. 1 is a cross-sectional view showing the structure of a package according to the present invention. The metal plate 1 is formed into a metal container having an opening by drawing, and a flange 2 is simultaneously formed in the opening. At this time, in order to fill a glass material 3 described later, it is desirable to process the metal container bottom so as to be thick. And metal plate 1
A plurality of holes are formed in the bottom of the substrate, and the holes are filled with a glass material 3 to allow the plurality of lead terminals 4 to be airtightly penetrated, and this is used as a base B. Further, the supports S1 and S2 are welded and fixed to the tip of the lead terminal 4, and the piezoelectric vibrating element Y is placed on the flat portion of the arm of the supports S1 and S2. . Then, a metal lid H having a slightly concave portion formed in the center of the metal plate to increase the strength is placed on the flange 2 and hermetically sealed by means such as cold welding or resistance welding to form a piezoelectric vibrator. I do.

The feature of the present invention resides in that the metal plate 1 of the base B is deep drawn, and a flange 2 for press contact is formed in the opening thereof. In this manner, the flange 2 is separated from the lead terminal 4 as much as possible, so that the strain during pressing (or welding) is not applied to the glass material 3. The thickness required for fixing can be reduced, and the height of the piezoelectric vibrator can be reduced.

FIG. 2 is a sectional view showing the structure of a second embodiment according to the present invention, in which metallization is applied to the outer periphery of the side surface of a circular ceramic substrate 11 and a flange 12 is provided at one opening in the metallization. The formed metal cylinder 13 is brazed with silver as shown in FIG. A plurality of external terminal electrodes 14 that are electrically connected to internal terminal electrodes (not shown) are provided at the end of the outer bottom surface of the circular ceramic plate 11. Furthermore, the supports S1 and S2 are welded to the internal terminal electrodes (not shown), the piezoelectric vibrating element Y is placed on the flat portions of the arms of the supports S1 and S2, and both are conductively fixed with the conductive substance 16. Then, a metal lid H having a slightly concave portion formed in the center of the metal plate is placed on the flange 12 and hermetically sealed by means such as cold welding or resistance welding to form a piezoelectric vibrator.

With the package structure shown in FIG. 2, distortion generated when the metal cover H is pressed (or welded) to the flange 12 of the base B is absorbed by the metal cylinder 13 because the metal cylinder 13 is long. And the ceramic 11 to which silver brazing is applied will not crack. Therefore, since the ceramic 11 can be made thin, the base B becomes thin, and the height of the piezoelectric vibrator can be reduced. Further, as shown in FIG. 3, a concave portion is formed on the outer bottom surface of the ceramic substrate, and the external terminal electrode 14 is also formed in the concave portion.
May be arranged, for example, an electronic component such as the power transistor 15 constituting the oscillation circuit may be arranged in the recess. With such a configuration, a part of the electronic component can be accommodated in the recess of the base of the package, so that there is an advantage that it contributes to downsizing of the piezoelectric oscillator.

In the above example, two supports are shown. However, three or four supports generally used for holding a low-frequency piezoelectric substrate on the piezoelectric vibrating element Y are provided. It is needless to say that the present invention may be applied to other objects.

FIG. 4 is a view showing a structure of a base and a support according to another embodiment of the present invention. FIG. 4A shows the support material 31.
(B) is a plan view in which the support material 31 is welded to the lead terminal 32 of the base B, and (c) is a view in which the support material 31 is welded to (b)
FIG. 4D is a perspective view of the base B cut by using a laser or the like along the dotted line, and FIG. 4D is a perspective view of a piezoelectric vibrating element Y placed on the base B and electrically conductively fixed to each other by a conductive material 33. . First, a small rectangular metal piece is processed into a bow shape as shown in FIG.
Form 31. Then, as shown in the plan view of FIG. 4B, of the four lead terminals 32 which hermetically penetrate the glass material of the base B, two lead terminals 32, 32 symmetric with respect to the center of the base B. The support material 31 is welded to each. Then, cutting is performed by using a laser or the like along a broken line 33 shown in FIG. 4B to obtain supports S1, S2, S3 and S4 which are independent from each other as shown in FIG. 4C.

FIG. 4D shows the base B thus formed.
Place the piezoelectric vibrating element Y on the supports S1, S2, S3, S4 of
FIG. 3 is a perspective view of a state where both are conductively fixed with a conductive material 34. By using the support material 31, the support S1, S3
Alternatively, the interval between S2 and S4 becomes constant, and it is possible to fix them so as to exactly face each other.
Welding is possible only by using a simple jig,
Welding man-hours can be reduced. FIG.
The support may be manufactured using a cross-shaped support material in which two support materials shown in FIG. That is, the support can be easily realized by using a metal plate having at least two tongue-shaped pieces radially from the center.

[0014]

According to the present invention, as described above, a metal plate is drawn into a container shape and a flange is formed at an opening thereof, or a flange is formed at one end on the outer periphery of a ceramic substrate. By using the formed metal cylinder as a base for brazing silver, distortion during pressure welding (or resistance welding) can be reduced, so that the thickness of the base can be reduced, and the piezoelectric vibration with a reduced height The child was able to be realized. In addition, a piezoelectric vibrator using a base in which a concave portion is provided in a ceramic bottom and electronic components are accommodated therein, or a base in which a wiring pattern is formed on the ceramic bottom can be reduced in height, and the vibrator was used. This represents an excellent effect that it can greatly contribute to downsizing of the piezoelectric oscillator.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view when a piezoelectric vibration element is mounted on a support of a package according to the present invention.

FIG. 2 is a cross-sectional view when a piezoelectric vibration element is mounted on a support of a second package according to the present invention.

FIG. 3 is a cross-sectional view when a piezoelectric vibration element is mounted on a support of a third package according to the present invention.

4A is a plan view of a support material, FIG. 4B is a plan view of the base material welded to the support material, FIG. 4C is a perspective view of the base material obtained by cutting the support material, and FIG. It is.

FIG. 5 is a cross-sectional view in which a piezoelectric vibration element is mounted on a conventional package.

FIG. 6 is a cross-sectional view in which a piezoelectric vibration element is mounted on another conventional package.

FIG. 7A is a perspective view of a base of a conventional package,
(B) is a perspective view of the support, and (c) is a side view of the support.

[Explanation of symbols]

 1. Metal plate processed into container shape 2, 12, Flange 3, Glass material 4, 32, Lead electrode 5, 16, 34, Conductive substance B, Base H, Metal cover S1, S2 , S3, S4 ... Support Y ... Piezoelectric vibrating element 11, 21 Ceramic 13 Metal cylinder 14 Terminal electrode 15 Electronic component 22 Electrical wiring 31 Support material 33 Support material Dashed line above

Claims (3)

[Claims] 1. A metal container having an opening, wherein a flange is formed in the opening, a plurality of holes are formed in the bottom of the metal container, and a plurality of lead terminals are hermetically penetrated using a glass material in the holes. The structure of the package for a piezoelectric vibrator, wherein the piezoelectric vibrator can be hermetically sealed by joining the flange and a peripheral portion of a plate-shaped metal lid. 2. A metal cylinder having a flange formed in one opening, the other opening of which is closed by a ceramic substrate having an electrode hermetically penetrating between both main surfaces, and said flange and a plate-like metal lid are provided. A structure of a package for a piezoelectric vibrator, wherein the package is bonded to a peripheral portion of the piezoelectric vibrator. 3. A method of mounting a support member on a lead terminal provided on a base of a package, comprising: forming a metal plate having at least two tongue-like pieces radially from a center; Manufacturing a package for a piezoelectric vibrator, characterized in that after fixing the vicinity of the base of each tongue to the lead terminal by welding, the central portion of the metal plate is cut off from each tongue. Method.