JPH11177373A - Container for storing piezoelectric vibrator - Google Patents

Abstract

(57) [Summary] The reliability of hermetic sealing of a container accommodating a piezoelectric vibrator is low. An insulating base (1) having a rectangular parallelepiped recess (1a) for accommodating a piezoelectric vibrator (3) on its upper surface, and a frame-shaped metal layer (7) attached around the recess (1a); And a pair of squares having a wiring layer 6 formed inside the end of the concave portion 1a and having one end of the piezoelectric vibrator 3 fixed thereto with an adhesive 5 on the upper surface. In a piezoelectric vibrator storage container including stepped portions 4 and 4 having a shape and a metal lid 2 welded to the metal frame 8 and closing the recess 1a, corner portions of the pair of stepped portions 4 and 4 are provided. A is chamfered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for accommodating a piezoelectric vibrator such as a quartz vibrator or a ceramic vibrator.

[0002]

2. Description of the Related Art Conventionally, a container for accommodating a piezoelectric vibrator such as a quartz vibrator or a ceramic vibrator has a piezoelectric vibrator 24 on its upper surface as shown in FIGS. 3 and 4, for example.
An insulating base 21 having a rectangular parallelepiped concave portion 22 for accommodating therein, and a frame-shaped metal layer 23 attached around the concave portion 22, and a metal frame member brazed to the metal layer 23 25, and a pair of square steps 27, 2 having a wiring layer 26 formed inside the end of the recess 22 and having one end of the piezoelectric vibrator 24 fixed on the upper surface thereof with an adhesive.
7 and a metal lid 28 welded to the metal frame 25 to close the recess 22.
One end of the piezoelectric vibrator 23 is bonded and fixed to the upper surface of the piezoelectric vibrator 27 via an adhesive made of a brazing material or a conductive resin, and the metal frame 25 is made of a metal made of an iron-nickel-cobalt alloy, The lid 28 is welded by a seam welding method or the like, and the piezoelectric vibrator 24 is hermetically accommodated in a container including the insulating base 21 and the metal lid 28, thereby forming a piezoelectric device as a final product.

The insulating substrate 21 is generally made of a sintered body of aluminum oxide, and is mixed with a raw material powder of aluminum oxide, silicon oxide, magnesium oxide, calcium oxide and the like by adding an appropriate organic solvent and a solvent to form a slurry. At the same time, the slurry is formed into a sheet by a doctor blade method, a calendar roll method, or the like to obtain a ceramic green sheet, and then the ceramic green sheet is subjected to a predetermined punching process, and a plurality of the ceramic green sheets are laminated one above the other. , At about 1600 ° C.

The frame-shaped metal layer 23 and the wiring layer 26
Is formed of a high melting point metal such as tungsten, molybdenum, and manganese. For example, an organic solvent is added to a powder of tungsten or the like and a solvent is added and mixed. By printing and applying in a predetermined pattern in advance by a conventionally known screen printing method or the like, it is formed at a predetermined position on the insulating base 21 by co-firing with the insulating base 21.

Further, the metal frame 25 brazed to the frame-shaped metal layer 23 is made of an iron-nickel-cobalt alloy, an iron-nickel alloy, or the like. Has been attached through.

[0006]

However, in this conventional container for storing a piezoelectric vibrator, a piezoelectric vibrator such as a quartz vibrator or a ceramic vibrator is accommodated inside a concave portion of an insulating base, and a metal frame is provided in a metal frame. When manufacturing the piezoelectric device by attaching the lid-forming body by welding, only the metal frame greatly expands and contracts during welding to generate stress between the insulating base and the metal frame. Concentration acts on the corners of the square step, causing cracks and cracks in the insulating base located below the corners of the step, breaking the hermetic seal of the container and, as a result, accommodating the inside of the container There is a disadvantage that the piezoelectric vibrator cannot be operated normally and stably for a long period of time.

The present invention has been devised in order to solve the above-mentioned drawbacks. The object of the present invention is to improve the reliability of hermetic sealing of a container, and to make a piezoelectric vibrator housed in the container normal, Another object of the present invention is to provide a container for accommodating a piezoelectric vibrator that can be operated stably.

[0008]

According to the present invention, there is provided an insulating substrate having a rectangular parallelepiped recess for accommodating a piezoelectric vibrator provided on an upper surface thereof, and a frame-shaped metal layer provided around the recess.
A pair of square frames each having a metal frame brazed to the metal layer and a wiring layer formed inside the end of the concave portion and having one end of the piezoelectric vibrator fixed on an upper surface via an adhesive; In a piezoelectric vibrator storage container comprising a step portion and a metal lid welded to the metal frame and closing the recess,
The corners of the pair of steps are chamfered.

Further, the present invention is characterized in that the corners of the pair of steps are chamfered in an arc shape having a radius of 0.07 mm to 0.5 mm.

According to the container for accommodating the piezoelectric vibrator of the present invention,
Since the corners of the pair of square steps formed inside the concave portion of the insulating base are subjected to, for example, arc-shaped chamfering with a radius of 0.07 mm to 0.5 mm, the inside of the concave portion of the insulating base is When accommodating a piezoelectric vibrator such as a crystal vibrator or a ceramic vibrator and attaching a metal lid to the metal frame by welding, when manufacturing a piezoelectric device, only the metal frame has a large thermal expansion and heat during welding. Even if stress is generated between the insulating base and the metal frame due to shrinkage, the stress does not concentrate on the corners of the step portion having a square shape, and as a result, the lower portion of the step portion has a lower portion. Cracks and cracks are effectively prevented from occurring in the insulating substrate located in the container, and the piezoelectric vibrator housed inside the container operates normally and stably for a long time with high reliability of hermetic sealing of the container. It is possible to do.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to the accompanying drawings. 1 and 2 show one embodiment of a container for accommodating a piezoelectric vibrator according to the present invention, wherein 1 is an insulating base made of an electrically insulating material, and 2 is a lid made of a metal material. The insulating base 1 and the metal lid 2 constitute a container for accommodating the piezoelectric vibrator 3.

The insulating substrate 1 has a piezoelectric vibrator 3 on its upper surface.
Is provided with a rectangular parallelepiped concave portion 1a which forms a space for accommodating the rectangular shape, and a pair of rectangular step portions 4, 4 are formed inside one end of the concave portion 1a.

The step portions 4 and 4 function as a support member for supporting the piezoelectric vibrator 3, and the piezoelectric vibrator 3 is bonded and fixed to the upper surfaces of the step portions 4 and 4 via an adhesive 5.

To fix the piezoelectric vibrator 3 to the step portions 4 and 4 via the adhesive 5, the piezoelectric vibrator 3 is first placed on the upper surfaces of the step portions 4 and 4, for example, silver-epoxy or polyimide-based conductive material. This is performed by placing an adhesive 5 made of a conductive resin in between, and then subjecting the adhesive 5 to a thermosetting treatment and thermosetting.

[0015] Further, the pair of square step portions 4,
The corners A of the step 4 are chamfered to prevent stress from being concentrated on the corners A of the steps 4 and 4 having a square shape.

The chamfering performed on the corners A of the step portions 4 and 4 is preferably C surface processing or R surface processing. Particularly, in the case of chamfering by the R surface processing, the corners A of the step portions 4 and 4 are preferably formed. There is no angular portion at all, and the concentration of stress can be completely eliminated. Therefore, it is preferable that the corners A of the steps 4, 4 are chamfered by R-surface processing.

The corner portions A of the step portions 4 and 4 having the square shape
When the radius of the circular arc is less than 0.07 mm, stress cannot be effectively prevented from concentrating on the corner A of the steps 4, 4, if the radius of the arc is less than 0.07 mm.
If it exceeds 5 mm, the areas of the steps 4 and 4 become small, and it becomes difficult to firmly fix the piezoelectric vibrator 3 to the steps 4 and 4. Therefore, the corner portions A of the step portions 4, 4 forming the square shape
When chamfering is performed by R-surface processing, the radius of the circular arc is preferably set in the range of 0.07 mm to 0.5 mm.

The insulating substrate 1 and the pair of steps 4 are made of an aluminum oxide sintered body, a mullite sintered body, an aluminum nitride sintered body, a silicon carbide sintered body, a glass ceramic sintered body. When it is made of, for example, an aluminum oxide sintered body, an appropriate organic binder or solvent is added to the raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide. The slurry is formed into a ceramic green sheet (ceramic green sheet) by employing a doctor blade method or a calender roll method. Thereafter, the ceramic green sheet is subjected to an appropriate punching process. Are stacked on each other, and about 1
It is manufactured by firing at a temperature of 600 ° C.

The chamfering process performed on the corners A of the step portions 4 having the quadrangular shape is performed, for example, when punching a ceramic green sheet to be the insulating substrate 1 by firing. 4 is performed by making the portion located at the corner A of the C-shaped or R-shaped surface.

Further, in the insulating substrate 1 having the pair of step portions 4, 4, a wiring layer 6 is formed from the upper surface of the step portions 4, 4 to the lower surface of the insulating substrate 1, and the step portion 4 of the wiring layer 6 is formed. The electrodes of the piezoelectric vibrator 3 are electrically connected to the region located on the upper surface of the piezoelectric vibrator 3 via an adhesive 5, and the wiring conductor of the external electric circuit board is provided at the region led out to the lower surface of the insulating base 1. It is brazed through a brazing material such as solder.

The wiring layer 6 is made of a high melting point metal powder such as tungsten, molybdenum, manganese or the like. A metal paste obtained by adding a suitable organic binder and a solvent to the metal powder is mixed and fired to form an insulating substrate 1. By printing and applying a predetermined pattern on a predetermined position of the formed ceramic green sheet in advance by a conventionally known screen printing method, the ceramic green sheet is adhered and formed from the upper surfaces of the step portions 4 and 4 to the lower surface of the insulating base 1.

When the wiring layer 6 is coated with a metal having excellent corrosion resistance and good conductivity, such as nickel and gold, on its exposed outer surface to a thickness of 1 to 20 μm by plating. It is possible to effectively prevent oxidative corrosion of the wiring layer 6 and to strengthen the brazing strength when the wiring layer 6 is brazed to a wiring conductor that is broken by an external heating circuit via a brazing material such as solder. Can be. Therefore, it is preferable that the metal such as nickel or gold is applied to the exposed outer surface of the wiring layer 6 to a thickness of 1 to 20 μm.

The insulating substrate 1 has a recess 1a on its upper surface.
A frame-shaped metal layer 7 is formed around the metal frame 7, and a metal frame 8 is brazed to the frame-shaped metal layer 7 via a brazing material 9.

The frame-shaped metal layer 7 attached to the upper surface of the insulating base 1 is made of a high melting point metal such as tungsten, molybdenum, manganese or the like. It acts as a base metal layer when attaching.

The frame-shaped metal layer 7 is formed by sintering a metal paste obtained by adding an appropriate organic binder and a solvent to a metal powder such as tungsten or the like, and baking the metal paste to a predetermined position on the ceramic green sheet to be the insulating substrate 1. A frame is formed around the concave portion 1a on the upper surface of the insulating substrate 1 by printing and applying a frame in advance by a conventionally known screen printing method.

The metal layer 7 is preferably formed by coating a metal having excellent corrosion resistance such as nickel and gold and having good wettability with a brazing material to a thickness of 1 to 20 μm on the exposed surface by plating. In addition, the oxidation corrosion of the metal layer 7 can be effectively prevented, and the brazing between the metal layer 7 and the metal frame 8 can be made firm. Therefore, the metal layer 7 is coated with a metal having excellent corrosion resistance, such as nickel and gold, and a good wettability with a brazing material by a plating method.
Preferably, it is applied to a thickness of from 20 to 20 μm.

Further, a metal frame 8 brazed to the frame-shaped metal layer 7 via a brazing material 9 insulates the metal lid 2 made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy. It acts as a base metal member when it is attached to the base 1 by welding, and the metal cover 2 is welded to the metal frame 8 by a seam welding method or the like.
Is attached on the insulating substrate 1.

The metal frame 8 is made of a metal material such as an iron-nickel-cobalt alloy or an iron-nickel alloy, and is conventionally known in the art such as a rolling method and a punching method for ingots of iron-nickel-cobalt alloy. Is formed in a predetermined frame shape by applying the metal working method of (1).

The metal frame 8 is brazed to a frame-shaped metal layer 7 provided on the upper surface of the insulating base 1 with a brazing material 9 interposed therebetween, for example, a silver-copper alloy. Silver brazing material such as is preferred.

The attachment of the metal frame 8 to the metal layer 7 via the brazing material 9 is performed by sequentially mounting the brazing material 9 previously punched into a frame shape on the metal layer 7 and the metal frame 8. After that, this is heated to a temperature of about 850 ° C., and the brazing material 9 is heated and melted.

Thus, according to the above-described container for accommodating the piezoelectric vibrator, the piezoelectric vibrator 3 is formed on the pair of rectangular step portions 4 formed in the rectangular parallelepiped concave portion 1a of the insulating base 1. -Attach via an adhesive 5 made of an epoxy or polyimide conductive resin and electrically connect the electrodes of the piezoelectric vibrator 3 to the wiring layer 6, and then around the recess 1a on the upper surface of the insulating base 1 The metal cover 2 is welded to the metal frame 8 brazed to the formed frame-shaped metal layer 7 by a seam welding method or the like, and a piezoelectric vibrator is placed inside the container including the insulating base 1 and the metal cover 2. 3 is hermetically sealed to complete a piezoelectric device as a final product.

In this case, since the corners A of the step portions 4 and 4 having a square shape are chamfered, when the metal lid 2 is attached to the metal frame 8 by welding, only the metal frame 8 is welded. Greatly expands and contracts due to heat during welding, the insulating base 1 and the metal frame 8
Even if stress is generated between the step portions 4 and 4, the stress does not concentrate on the corner portions A of the step portions 4 and 4 having a square shape. Cracks, cracks, etc. do not occur in the insulating substrate 1 located, and the reliability of hermetic sealing of the container is enhanced, and the piezoelectric vibrator 3 housed inside the container is operated normally and stably for a long period of time. Becomes possible.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. Although it has been described that the wiring layer 6 extending to the lower surface is directly connected to the wiring conductor of the external electric circuit board, the external lead terminals are previously brazed to the wiring layer 6 and the external lead terminals are connected to the external electric circuit. Thus, the piezoelectric vibrator housed inside the container may be connected to an external electric circuit.

[0034]

According to the container for accommodating the piezoelectric vibrator of the present invention, for example, a radius of 0.07 mm to 0.1 mm is formed at a corner of a pair of square steps formed inside the concave portion of the insulating base. Since a 5 mm arc-shaped chamfer was applied, a piezoelectric vibrator such as a crystal vibrator or a ceramic vibrator was accommodated in the concave portion of the insulating base, and a metal lid was attached to the metal frame by welding. When manufacturing the device, even if only the metal frame body undergoes large thermal expansion and contraction during welding and stress is generated between the insulating base and the metal frame body, the stress is applied to the corners of the square step. It does not act in a concentrated manner, and as a result, cracks and cracks are effectively prevented from being generated in the insulating base located below the corner of the step, and the reliability of hermetic sealing of the container is increased. The piezoelectric vibrator housed inside the container is extended for a long time Normal, and it is possible to stably operate.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a container for accommodating a piezoelectric vibrator according to the present invention.

FIG. 2 is a perspective view of an insulating base of the container shown in FIG.

FIG. 3 is a sectional view of a conventional container for accommodating a piezoelectric vibrator.

FIG. 4 is a perspective view of an insulating base of the container shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating base 1a ... Depression 2 ... Metal lid 3 ... Piezoelectric vibrator 4 ... Step part 5 ... Adhesive 6 ... Wiring layer 7 ··· Frame-shaped metal layer 8 ··· Metal frame A ··· Corner of step

Claims (2)

[Claims] An insulating base having a rectangular parallelepiped recess for accommodating a piezoelectric vibrator provided on an upper surface thereof and a frame-shaped metal layer attached around the recess, and brazing to the metal layer. A metal frame, a pair of square steps having a wiring layer formed on the inner side of the end of the recess and having one end of the piezoelectric vibrator fixed on the upper surface via an adhesive, and the metal frame Wherein the corners of the pair of steps are chamfered, wherein the corners are chamfered. 2. The corner of the pair of steps has a radius of 0.07 m.
The container for accommodating a piezoelectric vibrator according to claim 1, wherein the container is chamfered in an arc shape of m to 0.5 mm.