JPH0477010A - Manufacture of package for containing piezoelectric resonator - Google Patents

Abstract

PURPOSE:To bond a metal made support member to a metallized metallic layer strongly in a short time and to realize an inexpensive and highly reliable piezoelectric vibrator by causing solid phase diffusion bonding between the metallized metal layer and the metal made support member with by means of an ultrasonic wave vibration energy. CONSTITUTION:A metal made support member 6 is placed on a metallized metallic layer 5 and while pressing an ultrasonic wave oscillating horn onto an upper face of the metal made support member 6 under a pressure of nearly 1.5-6.5kg/mm<2>, ultrasonic wave vibration whose amplitude is nearly 10-30mum and whose vibration is nearly 30-50kHz is applied for nearly 0.01-0.2sec and solid phase diffusion bonding is caused through interdiffusion between the metallized metallic layer 5 and the metal made support member 6. Thus, the bonding strength between the metal made support member and the metallized metallic layer is much strengthened and the bonding workability and the mass- productivity of the metal made support member are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a piezoelectric vibrator housing package for housing a piezoelectric vibrator made of crystal, piezoelectric ceramics, or the like.

(Prior Art) Conventionally, as shown in Fig. 2, a piezoelectric resonator storage package for accommodating a piezoelectric resonator is made of an electrically insulating material such as alumina ceramics, and has a metallized metal layer drawn from the top surface to the bottom surface. an insulating substrate 11 having 12
, a pair of metal holding members 14 for holding the piezoelectric vibrator 15 bonded to the metallized metal layer 12 via a conductive adhesive 13, and a bowl-shaped lid 16. After bonding both ends of the piezoelectric vibrator 15 to the metal holding member 14 using a conductive adhesive and holding the piezoelectric vibrator 15 to the metal holding member 14, the lid 16 is opened in a nitrogen atmosphere or dry air. The piezoelectric vibrator 15 is sealed as a final product by bonding the lower surface to the insulating base 11 via a sealing material 17 made of low-melting glass, and hermetically sealing the piezoelectric vibrator 15 inside a container consisting of the insulating base 11 and the lid 16. It becomes a vibrating element.

Incidentally, the piezoelectric vibrator housing package is usually manufactured by using the insulating base 11 to which the metal holding member 14 is adhered, or by the following method.

(i) First, metallized metal layer 1 from the top surface to the bottom surface.
An insulating base 11 and a metal holding member 14 are prepared.

(ii) Next, the metallized metal layer 12 of the insulating base II
One end of the metal holding member 14 is placed on top with the adhesive 13 made of polyimide-based conductive resin sandwiched therebetween, and (ii) finally, heat at 300° C. is applied to the adhesive 13 for 30 minutes to 1 hour. By thermally curing the adhesive 13, the metal holding member 14 is bonded to the metallized metal layer 12 with electrical continuity, thereby bonding the metal holding member 14 to the upper surface used for the package for housing the piezoelectric vibrator. This results in an insulating base 11.

(Problem to be Solved by the Invention) However, according to this conventional piezoelectric vibrator storage package, polyimide is used on the metal holding member that holds the piezoelectric vibrator or on the metallized metal layer coated on the insulating substrate. They are bonded via an adhesive made of a polyimide-based conductive resin, and the polyimide-based conductive resin has poor heat resistance. Therefore, when the piezoelectric vibrator is hermetically sealed inside a container consisting of the insulating base and the lid by heating and melting a sealing material made of low-melting glass to bond the lid to the insulating base, the sealing material is heated. When melting heat (approximately 420°C) is applied to the adhesive bonding the metal holding member to the metallized metal layer of the insulating substrate, a portion of the adhesive will thermally decompose, resulting in The adhesive strength of the metal holding member decreases, and if an impact force is applied to the piezoelectric vibrating element due to a fall, etc., the metal holding member will come off from the metallized metal layer, and the function as a piezoelectric vibrating element will be lost. had.

In addition, the adhesive used to bond the metal holding member to the metallized metal layer of the insulating substrate must be heated at 300"C for 30 minutes to 1 hour to harden, requiring a long time to bond the metal holding member. As a result, the workability and mass productivity of adhering the metal holding members were extremely poor, and as a result,
It also has the disadvantage of making the piezoelectric vibrating element as a final product expensive.

(Object of the Invention) The present invention was devised in view of the above-mentioned drawbacks, and its purpose is to make it possible to firmly adhere a metal holding member to a metallized metal layer in a short period of time, and to achieve a high reliability at low cost. An object of the present invention is to provide a method for manufacturing a package for housing a piezoelectric vibrator, which allows obtaining a piezoelectric vibrating element.

(Means for Solving the Problems) The present invention provides an insulating base having a metallized metal layer on its upper surface and a metal holding member for holding a piezoelectric vibrator, and a metal holding member on the metallized metal layer of the insulating base. The metal holding member is placed on the metal holding member and ultrasonic vibration energy is applied from above the metal holding member to cause solid phase bonding between the metallized metal layer and the metal holding member through mutual diffusion. It is characterized by adhering the metallized metal layer to the metallized metal layer.

(Example) Next, the present invention will be described in detail based on an example shown in the accompanying drawings.

FIG. 1 shows an embodiment of a package for housing a piezoelectric vibrator manufactured by the manufacturing method of the present invention, where l is an insulating base made of an electrically insulating material such as alumina ceramics, and 2 is a bowl-shaped piece made of an electrically insulating material. This is the lid body. The insulating base 1 and the lid 2 constitute a container 3 for accommodating the piezoelectric vibrator 4.

The insulating substrate is made of ceramics such as aluminum oxide sintered body, zirconium oxide sintered body, mullite sintered body, aluminum nitride sintered body, etc., and is coated with tungsten, molybdenum, silver, etc. from the top surface to the bottom surface. A metallized metal layer 5 made of metal powder such as palladium, copper, or nickel is deposited.

The metallized wiring layer 5 deposited on the insulating substrate 1 serves to electrically connect the electrodes of the piezoelectric vibrator 4 housed inside to the external electric circuit board, and the upper surface of the insulating substrate 1 of the metallized metal layer 5 The electrodes of the piezoelectric vibrator 4 are electrically connected to each other via a metal holding member 6, which will be described later, and the insulating base I
The wiring conductor of the external electric circuit board is bonded to the bottom surface of the board through a brazing material such as solder.

Further, one end of a metal holding member 6 for holding the piezoelectric vibrator 4 is bonded on the metallized metal layer 5,
The metal holding member 6 functions to hold the piezoelectric vibrator 4 and connect the electrodes of the piezoelectric vibrator 4 to the metallized metal layer 5.

The metal holding member 6 is attached to the metallized metal layer 5 by placing the metal holding member 6 on the metallized metal layer 5,
This is done by causing solid phase bonding through mutual diffusion of the two in the mounting section, and the adhesive strength is 20.
It is as strong as 0 gf/mm2 or more, and even if an impact force is applied to the metal holding member 6, the metal holding member 6 will not come off from the metallized metal layer 5.

Thus, in this piezoelectric vibrator storage package, both ends of the piezoelectric vibrator 4 are bonded to a pair of metal holding members 6 bonded to the metallized metal layer 5 of the insulating base 1 using an adhesive made of polyimide-based conductive resin. At the same time, the electrodes of the piezoelectric vibrator 4 are electrically connected to the metal holding member 6, and then the lower surface of the bowl-shaped lid 2 is placed on the upper surface of the insulating substrate L in a nitrogen atmosphere or dry air. The piezoelectric vibrator 4 is hermetically sealed inside a container 3 consisting of an insulating base l and a lid 2, thereby forming a piezoelectric vibrating element as a final product.

Next, a method for manufacturing an insulating substrate of a package for housing a piezoelectric vibrator according to the present invention will be explained.

First, an insulating substrate l having a metallized metal layer 5 from the top surface to the bottom surface shown in FIG. 1 and a metal holding member 6 are prepared.

The insulating substrate l is made of a ceramic such as an aluminum oxide sintered body or a zirconium oxide sintered body. For example, when it is made of an aluminum oxide sintered body, a suitable raw material powder such as alumina, magnesia, calcia, or silica is used. A ceramic green sheet (ceramic raw sheet) is formed by adding and mixing an organic solvent and a solvent to form a slurry and using a doctor blade method.Then, the ceramic green sheet is punched into an appropriate shape. It is manufactured by applying and firing at high temperature (approximately 1600'C).

Further, the metallized metal layer 5 extending from the top surface to the bottom surface of the insulating substrate l is formed of a high melting point metal powder such as tungsten or molybdenum, or a metal powder such as silver, silver-palladium, copper, or nickel.

In addition, when the metallized metal layer 5 is made of powder of a high melting point metal such as tungsten or molybdenum, a metal paste obtained by adding and mixing the high melting point metal powder with a suitable organic solvent or solvent is used as a ceramic green material to form the insulating substrate 1. The ceramic green sheet and the metal paste are applied by printing from the top surface to the bottom surface, and then fired at a high temperature (approximately 1600'C) to sinter and integrate the ceramic green sheet and the metal paste. The exposed outer surface is coated with nickel, in order to effectively prevent oxidation corrosion of the metallized metal layer 5 and to firmly bond the metal holding member described later.
It is plated with metal such as gold to a thickness of 1.0 to 20.0 μm.

Further, when the metallized metal layer 5 is made of metal powder such as silver, silver-palladium, copper, nickel, etc., a metal paste obtained by adding and mixing a suitable organic solvent or solvent to metal powder such as silver is applied to the insulating substrate. It is formed by printing and coating from the top surface to the bottom surface of 1, and then firing and baking it at a high temperature.

The metal holding member 6 is made of nickel silver (Cu-Zn-Ni alloy), Kovar (Fe-Ni-Co alloy), 42A]
Ioy (FeNi alloy), 5LIS (Fe-Cr-
It is made of elastic metals such as Ni alloy), silver solder (Ag-Cu alloy), etc. For example, when it is made of Kovar, it is made of iron (
Fe), nickel (Ni), and cobalt (Co) are weighed to predetermined values, heated and melted and alloyed to make a Kovar ingot, and the ingot is formed into a thin plate shape by a rolling process. It is formed by punching a thin Kovar plate into a predetermined shape using a conventionally well-known punching process.

Next, as shown in FIG. 1, the metal holding member 6 is adhered onto the metallized metal layer 5 of the insulating base 1, and thereby the metal holding member 6 is adhered to the upper surface used for the package for housing the piezoelectric vibrator. This results in an insulating base l.

The metal holding member 6 is bonded to the metallized metal layer 5 by placing the metal holding member 6 on the metallized metal layer 5 and applying ultrasonic vibration energy from above the metal holding member. 5 and the metal holding member 6 through mutual diffusion. Specifically, the metal holding member 6 is placed on the metallized metal layer 5 and the metal holding member 6 is placed on the metallized metal layer 5. 1.5 to 6.5 Kgf/mm from the top of the ultrasonic oscillation horn
2. While pressing with pressure, the frequency of vibration is 30 to 50KHz,
Ultrasonic vibration with an amplitude of IO to 30 μm was applied to 0. Ol~0.
The application is applied for 2 seconds, and the metallized metal layer 5 and the metal holding member 6 are
This is done by causing solid-phase bonding through interdiffusion between the two.

The adhesion of the metal holding member 6 to the metallized metal layer 5 is solid phase bonding by mutual diffusion between the metallized metal layer 5 and the metal holding member 6, and the bonding interface between the metal holding member 6 and the metallized metal layer 5 is Because it is an integrated product, its adhesive strength is as strong as 200 Kgf/mm2 or more, and even if an impact force is applied to the metal holding member 6, the impact force will cause the metal holding member 6 to separate from the metallized metal layer 5. Nothing will happen.

Furthermore, since the metal holding member 6 is bonded to the metallized metal layer 5 in an extremely short time of 0.01 to 0.2 seconds, the workability and mass productivity of bonding the metal holding member 6 are extremely good. Accordingly, the piezoelectric vibrating element as a final product can be made extremely inexpensive.

In addition, when adhering the metal holding member 6 to the metallized metal layer 5 using the ultrasonic oscillation horn, the ultrasonic oscillation horn is pressed against the metal holding member 6 with a pressure of 3 to 4 Kgf/mm' and then vibrated. Several 35 to 40KHz, amplitude 15
When ultrasonic vibration of 20 μm to 20 μm is applied, the metal holding member 6 is attached to the metallized metal layer 5 by 0.0 μm. It is possible to bond firmly in a short time of 0.1 to 0.1 seconds. Therefore,
In order to firmly bond the metal holding member 6 to the metallized metal layer 5 in a short time, the metal holding member 6 is placed on the metallized metal layer 5, and the placing part is heated with a vibration frequency of 35 to 40K.
It is preferable to irradiate ultrasonic vibration energy of Hz and amplitude of 15 to 20 μm.

In addition, when the metal holding member 6 is bonded to the metallized metal layer 5 using ultrasonic vibration energy, pressure scratches are formed on the surface of the metal holding member 6 due to the pressure of the ultrasonic oscillation horn. Oxidative corrosion may occur. Therefore, the outer surface of the metal holding member 6 is plated with a metal with excellent corrosion resistance such as nickel or gold.
The outer surface of the metal holding member 6 is coated with nickel or nickel because the oxidation corrosion can be effectively prevented by coating it to a thickness of μm.
It is preferable to deposit a metal such as gold to a thickness of 1.0 to 20.0 μm.

(Experiment example) Next, the effects of the present invention will be explained based on experimental examples.

First, 20 metalized metal layers made of tungsten each having a width of 2 mm, a length of 2 mm, and a thickness of about 15 μm were deposited on the surface of an insulating substrate made of an aluminum oxide sintered body.
Next, on each metallized metal layer, a layer with a width of 1 mm and a length of 5 mm is placed.
, one end of a metal piece made of Kovar with a thickness of 0.08 mtn was placed, and an ultrasonic oscillation horn was pressed against the placing part with a force of about 4 Kgf/mm2, and the vibration frequency was 38 KH.
z, by applying ultrasonic vibration with an amplitude of 16 μm for about 0.1 seconds, the metal piece was placed on the metallized metal layer with a width of 1 mm and a length of 0.6 m.
m, adhesive area is 0.6 mm2, and then the insulating substrate to which the metal pieces are adhered is heat-treated at a temperature of about 420°C. After that, the end of each metal piece opposite to the adhesive part is attached to the adhesive surface. On the other hand, the metal piece was pulled at an angle of 90°, and the tensile strength when the metal piece was peeled off from the metallized metal layer was measured, and the average value was determined, and this was evaluated as the adhesive strength of the metal piece.

In addition, as a comparative sample, a metal piece made of Kovar was adhered to the same area on the metallized metal layer adhered to the insulating substrate using an adhesive made of polyimide conductive resin, and heat treated at approximately 420°C. Thereafter, the adhesive strength of the metal pieces was determined by the same method as above.

The above results are shown in Table 1.

As can be seen from the above experimental results, the adhesive strength of the metal pieces (conventional product) in which metal pieces are bonded to the metallized metal layer using an adhesive made of polyimide conductive resin is 90 gf/m on average.
m2, which is weak (m2), whereas a metal piece is bonded to a metallized metal layer using ultrasonic vibration energy (
It can be seen that the adhesive strength of the product of the present invention is 800 gf/mm2 on average, which is about 9 times that of the conventional product.

(Effects of the Invention) Thus, according to the manufacturing method of the present invention, a metal holding member is placed on the metallized metal layer of the insulating substrate, and ultrasonic vibration energy is irradiated to the placement part, so that the metallized metal layer and the metal Since the metal holding member is bonded to the metallized metal layer by causing solid-phase bonding between the metal holding members through mutual diffusion, the adhesive strength between the two is extremely strong, and an impact force can be applied to the metal holding member. Even if the impact force causes the metal holding member to become detached from the metallized metal layer, it is possible to completely prevent the metal holding member from coming off from the metallized metal layer.

It is also possible to make the piezoelectric vibrating element as a final product inexpensive by improving the workability of bonding the members and the ease of mass production.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of a piezoelectric vibrator housing package manufactured by the method of the present invention, and FIG. 2 is a cross-sectional view of a conventional piezoelectric vibrator housing package. 1... Insulating base 2... Lid body 4... Piezoelectric vibrator 5... Metallized wiring layer 6... Metallic holding member

Claims (1)

[Claims] An insulating base having a metallized metal layer on its upper surface and a metal holding member for holding a piezoelectric vibrator are prepared, and the metal holding member is placed on the metallized metal layer of the insulating base. At the same time, ultrasonic vibration energy is applied from above the metal holding member to cause solid phase bonding between the metallized metal layer and the metal holding member by mutual diffusion, thereby adhering the metal holding member to the metallized metal layer. A method for manufacturing a package for storing a piezoelectric vibrator, characterized in that: