JPH08102634A - Production of piezoelectric vibrator - Google Patents

Abstract

PURPOSE: To reduce equivalent resistance and to improve heat resistance by vacuum-baking a case body and a plug body with a piezoelectric vibration piece fixed to an inner lead within a range of temp. of semi-molten state of solder so that the plug body is airtightly pressed into the case body. CONSTITUTION: A piezoelectric vibrator 1 and a semiconductor 2 for electrically oscillating the vibrator 1 are arranged on a plane and electrically connected by a metallic thin wire 9 by wire bonding and an alloy layer 7 including solder 103 by welding through a metallic lead 5 to constitute an oscillation circuit. A piezoelectric vibration piece 102 with an electrode film 101 formed on its surface by vapor deposition or the like is soldered to the soldered inner lead 104 side prepared by soldering a plug body and solder 103 is airtightly pressed into a soldered metallic case as a sealing material. The solder 103 contains >=90% lead (Pb) and its melting temperature is >=260 deg.C.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to the structure of a piezoelectric oscillator.

[0002]

2. Description of the Related Art A conventional piezoelectric oscillator is disclosed in JP-A-6l-19.
No. 204, and in the structure as shown in FIG. 9, the piezoelectric vibrator 11, the semiconductor 12 that electrically oscillates the piezoelectric vibrator 11, and the metal lead that electrically connects them are resin-molded. It was The case body and plug body of the piezoelectric vibrator 11 used here have a lead content of 40% for the main reason of appearance.
% Solder or less, and the resonator element is soldered to the plug body with the solder having the composition described above, and the plug body using the solder having the composition as a shield material is vacuum-pressed into the case. .

[0003]

However, in the above-mentioned conventional technique, the SMT (Surface Mount Tech) is used.
When it is used as a component, it has a basic problem that when it is mounted on a board, the entire component reaches 220 to 260 ° C and is melted by a solder having a lead content of 40% or less. During high temperature aging, the gas released from inside the solder plating causes a characteristic deterioration of the frequency and equivalent resistance of the piezoelectric vibrator.

Therefore, the present invention solves the problems as described above, and the object thereof is 260 ° C.
It is an object of the present invention to provide a piezoelectric oscillator having heat resistance capable of withstanding the above SMT mounting and excellent in high temperature frequency aging characteristics.

[0005]

[Means for Solving the Problems]

(1) A piezoelectric oscillator of the present invention is a piezoelectric oscillator in which at least a piezoelectric vibrator, a semiconductor (IC) that electrically oscillates the piezoelectric vibrator, and a metal lead frame including a plurality of metal leads and tabs are resin-molded. In the piezoelectric vibrator, the case body plug body is also plated with solder having a lead content of 90% or more, and the vibrating piece is soldered to the plug body with the solder, and the vibrating piece is The soldered plug body is hermetically press-fitted into the case body via the solder.

(2) In the piezoelectric oscillator of the present invention, the lead terminal of the piezoelectric vibrator re-plated with the solder of the composition and the metal lead frame have an alloy layer containing the solder of the composition. It is characterized by being welded together.

(3) In the piezoelectric oscillator of the present invention, the piezoelectric vibrator and the semiconductor are arranged in front and back relation with respect to the metal frame, and the tab of the metal frame to which the semiconductor is fixed is , Is pushed in parallel to the plurality of lead surfaces toward the piezoelectric vibrator side and comes into contact with the case body of the piezoelectric vibrator in parallel, and electrically insulates the case body of the piezoelectric vibrator from the plurality of metal leads. It is characterized by ensuring the clearance of.

(4) In the piezoelectric oscillator of the present invention, the plug body to which the piezoelectric vibrating reed is soldered and the case body,
Vacuum baking is performed within the semi-molten state temperature of the solder bear pattern,
It is characterized by being press-fitted.

[0009]

1 (a) is a perspective view of a piezoelectric oscillator according to an embodiment of the present invention, FIG. 1 (b) is a sectional view of FIG. 1 (a),
2A is an assembly plan view showing another example of the piezoelectric oscillator, FIG. 2B is an assembly sectional view of FIG. 2A, and FIG.
FIG. 4 is a sectional view of a piezoelectric vibrator that constitutes the piezoelectric oscillator.
5 is a sectional view of a vibrating piece of the piezoelectric vibrator, FIG. 5 is a sectional view of a plug body of the piezoelectric vibrator, and FIG. 6 is a sectional view of a case body of the piezoelectric vibrator. The configuration of the embodiment will be described below. First, the piezoelectric vibrating piece 102 having the electrode film 101 shown in FIG. 4 formed by vapor deposition or the like is shown in FIG. 3 with the solder 103 on the side of the plug lead soldered 103 of the plug lead shown in FIG. The metal case 1 soldered in the same manner 106 and plated with the solder 103 as shown in FIG.
05 is hermetically press-fitted with the solder 103 shown in FIG. 3 as a shield material. The solder 103 is a solder having a lead (pb) content of 90% or more in the solder state diagram shown in FIG. 7, and the melting temperature is 260 ° C. or more. Further, the solder 103 is plated by plating as shown in FIG. 6 of the case body and FIG. 5 of the plug body. At this time, however, the organic component in the plating solution is mixed into the solder 103. There is a point, and if the piezoelectric vibrating piece 102 is sealed by hermetically press-fitting it as it is, the high temperature (normal temperature to 260
(Between ° C), the equivalent resistance value may extremely increase (sometimes reach 100% or more), significant frequency aging may occur, and oscillation may be stopped. Therefore, when the plug body FIG. 5 is vacuum-pressed into the case body FIG. 6, it is necessary to carry out heating baking and to release it to the outside. At this time, the baking temperature is the temperature in the shaded area surrounded by the eutectic line ab, the liquidus line ac, and the line having a lead content of 90% or more in FIG. 7. It is possible to release the components.

As a result, the increase of the equivalent resistance value at high temperature is
It is kept within a few percent.

As a first embodiment of the structure of the piezoelectric oscillator, as shown in FIG. 1 (b), the piezoelectric vibrator 1 and the piezoelectric pendulum 1 shown in the embodiment of the present invention described above are electrically connected. The semiconductor 2 to be oscillated is electrically connected to the piezoelectric vibrator 1 and the semiconductor 2 by the metal thin wire 9 by wire bonding through the metal lead 5 and the alloy layer 7 containing the solder 103 by welding. It constitutes an oscillator circuit. Further, the piezoelectric vibrator 1, the semiconductor 2, the metal lead 5, the metal thin wire 9
And is formed of resin 8.

As a second embodiment of the structure of the piezoelectric oscillator, as shown in FIGS. 2A and 2B, the piezoelectric vibrator FIG. 3 (1 in FIG. 2) and the piezoelectric vibrator 1 are electrically connected. The semiconductor 2 to be oscillated by the metal frame 3 is arranged in front and back relation with the metal frame 3, and the semiconductor 2 is fixed to the metal frame 3.
The tab 4 is pushed out toward the piezoelectric vibrator 1 and comes into contact with the piezoelectric vibrator 1 in parallel to ensure electrical insulation clearance between the piezoelectric vibrator 1 and the plurality of metal leads 5. This not only prevents electrical conduction between the piezoelectric vibrator 1 and the plurality of metal leads 5, but also prevents short circuits between the metal leads 5. With this structure, compared to arranging the piezoelectric vibrator and the semiconductor in the plane direction, it is approximately
2. Assembled in the thickness direction with the minimum total thickness of the components.

Further, the lead 6 of the piezoelectric vibrator 1 is connected to the metal lead 5 related to the electric oscillation by the solder 1 shown in FIG.
It is welded as an alloy layer 7 containing 03. Although the lead 6 does not necessarily require solder plating, the lead 6 is plated simultaneously with the inner side 104 when the solder plating 103 is performed on the plug body shown in FIG.
With the solder 103 still attached, the metal lead 5 is welded as an alloy layer containing the solder 103.

Finally, the entire structure including the piezoelectric vibrator 1, the semiconductor 2, the metal leads 5 and the tabs 4 is formed of a heat-resistant resin 8.

As described above, the assembly drawing 2 of the piezoelectric oscillator described in the embodiment is the essential point of the assembly, and the soldering portion 106 of the vibrating piece 102, the case 105 and the plug body 3103 of the plug body FIG. The connection between the lead 6 of the vibrator and the metal lead 5 is configured to have a heat resistance of 260 ° C. or higher, including the components.

The overall shape of the embodiment is the SOP type of the SMT-compatible flat package as shown in FIG. 1, but the application to the DIP type as a plug component can also be mentioned as the embodiment.

An application of the flat package to a J-BEND lead type is also given as an embodiment.

[0018]

As described above, according to the piezoelectric oscillator of the present invention, the case body and the plug body of the piezoelectric vibrator are plated with solder having a lead content of 90% or more and having excellent heat resistance, and Use as mount material, hermetic shield material, and
By welding the lead of the piezoelectric vibrator to the metal lead of the metal frame as an alloy layer containing solder having a lead content of 90% or more, it is possible to provide a piezoelectric oscillator capable of withstanding heat resistance of 260 ° C. or more. .

The case body and the plug body of the piezoelectric vibrator are vacuum-baked at a temperature in a semi-molten state, and
By press-fitting and sealing a solder containing at least% lead as a shield material, it is possible to provide a piezoelectric oscillator having a small equivalent resistance and excellent high temperature aging characteristics and high heat resistance.

Further, the piezoelectric vibrator and the semiconductor are arranged on both sides of the lead frame respectively, and the tabs of the lead frame are pushed out to ensure the insulation between the piezoelectric vibrator and the metal leads. It has an effect of providing a piezoelectric oscillator having excellent heat resistance.

[Brief description of drawings]

FIG. 1A is a perspective view showing an embodiment of a piezoelectric oscillator according to the present invention, and FIG. 1B is a main cross-sectional view of FIG. 1A (first embodiment).

FIG. 2 (a) is a main plan view (second section) of the assembly of FIG. 1 (a).
Example), (b) is a main cross-sectional view of FIG.
Example).

FIG. 3 is a sectional view showing an embodiment of a piezoelectric vibrator which is a component of the piezoelectric oscillator of the present invention.

FIG. 4 is a sectional view of a vibrating piece of the piezoelectric vibrator shown in FIG.

5 is a sectional view of the plug body of the piezoelectric vibrator shown in FIG.

FIG. 6 is a sectional view of a case body of the piezoelectric vibrator shown in FIG. 3;

FIG. 7 is a state diagram showing an embodiment of solder used for assembling the piezoelectric vibrator shown in FIG. 3;

FIG. 8 is a perspective view of an unconventional piezoelectric oscillator.

FIG. 9 is a main cross-sectional view of a conventional piezoelectric oscillator.

FIG. 10 is a cross-sectional view of a conventional piezoelectric vibrator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ...- Piezoelectric vibrator showing an embodiment of the present invention 2 ... Semiconductor 3 ... Metal lead frame 4 ... Lead frame tab 5 ... Plural leads 6・ ・ ・ Piezoelectric vibrator lead terminal 7 ・ ・ ・ Solder containing alloy layer 8 ・ ・ ・ ・ Resin 9 ・ ・ ・ ・ Metal fine wire 11 ・ ・ ・ Piezoelectric vibrator 12 ・ ・ ・ Semiconductor 18 ・ ・ ・Resin 101 ・ Electrode 102 ・ Piezoelectric vibrating piece 103 ・ Solder containing 90% or more lead 104 ・ Inner lead 105 of plug body ・ Case body 106 ・ Soldering part of piezoelectric vibrating piece 107 ・ Pressing Or welding tsuba

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[Procedure amendment]

[Submission date] July 24, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title: Piezoelectric vibrator manufacturing method

[Claims]

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing a piezoelectric vibrator.
About the law .

[0002]

2. Description of the Related Art A conventional piezoelectric vibrator is disclosed in JP-A-6l-19.
No. 204, and in the structure as shown in FIG. 9, the piezoelectric vibrator 11, the semiconductor 12 that electrically oscillates the piezoelectric vibrator 11, and the metal lead that electrically connects them are resin-molded. It was The case body and plug body of the piezoelectric vibrator 11 used here have a lead content of 40% for the main reason of appearance.
% Solder or less, the resonator element is soldered to the plug body with the above-mentioned solder, and the plug body is vacuum-pressed into the case using the above-mentioned solder as a shield material. .

[0003]

However, in the above-mentioned conventional technique, the SMT (Surface Mount Tech) is used.
When it is used as a component, it has a basic problem that when it is mounted on a board, the entire component reaches 220 to 260 ° C and is melted by a solder having a lead content of 40% or less. During high temperature aging, the gas released from inside the solder plating causes a characteristic deterioration of the frequency and equivalent resistance of the piezoelectric vibrator.

Therefore, the present invention solves the problems as described above, and the object thereof is 260 ° C.
A method for manufacturing a piezoelectric vibrator having heat resistance capable of withstanding the above SMT mounting and having excellent high temperature frequency aging characteristics is provided.
It is in the place of providing .

[0005]

[Means for Solving the Problems] Manufacturing of the piezoelectric vibrator of the present invention
The manufacturing method is piezoelectric vibration using tin-lead solder with a lead content of 90% or more.
The moving piece and the inner lead of the plug body, and
Airtight pressure is applied to the case body by using the solder as a shield material.
In a vacuum atmosphere
The case body and the piezoelectric vibrating piece
Baking the plug body fixed to the card,
It is characterized in that the lug body is press-fitted into the case body.
It

[0006]

PREFERRED EMBODIMENTS FIG. 1 (a) is a perspective view of the piezoelectric oscillator in an embodiment of the present invention, FIG. 1 (b), FIGS. 1 (a)
2A is an assembled plan view showing another example of the piezoelectric oscillator, FIG. 2B is an assembled sectional view of FIG. 2A, and FIG. 3 is a sectional view of the piezoelectric oscillator. 5 is a sectional view of the piezoelectric vibrator, FIG. 4 is a sectional view of the resonator element of the piezoelectric vibrator, and FIG.
6 is a sectional view of the plug body of the piezoelectric vibrator, and FIG. 6 is a sectional view of the case body of the piezoelectric vibrator. The configuration of the embodiment will be described below. First, the piezoelectric vibrating piece 102 having the electrode film 101 shown in FIG. 4 formed by vapor deposition or the like is shown in FIG. 3 with the solder 103 on the side of the plug lead soldered 103 of the plug lead shown in FIG. Like soldering 10
6, the solder 103 shown in FIG. 3 is hermetically press-fitted into the metal case 105 with the solder plating 103 shown in FIG. 6 as a shield material. The solder 103 is a solder solder phase diagram of lead (P b) of the content of more than 90% as shown in Figure 7, the melting temperature is in the 260 ° C or higher. In addition, the solder 103 is a case body formed by plating.
( FIG. 6) and the plug body (FIG. 5) are plated, but at this time, there is a problem that the organic component in the plating solution is entangled in the solder 103. If the piezoelectric vibrating piece 102 is enclosed by a high temperature (between normal temperature and 260 ° C.), the equivalent resistance value will extremely increase (sometimes reach 100% or more), significant frequency aging will occur, and oscillation will stop. It can be reached. Therefore, when the plug body ( FIG. 5) is press-fitted into the case body (FIG. 6) under vacuum, it is necessary to perform heating baking and release the plug body to the outside. At this time, the baking temperature is eutectic line ab, liquidus line ac, and lead content 90 in FIG.
The temperature is in the shaded area surrounded by a line of not less than%, and it is possible to sufficiently release the organic component by carrying out baking sealing in this state. As a result, the increase in the equivalent resistance value at high temperatures can be kept within several percent.

[0007] As a first example of a structure of the piezoelectric oscillator, an electrical piezoelectric vibrator 1 and the piezoelectric vibration element 1 shown in the embodiment of the present invention has been described as shown in FIG. 1 (b), the more The semiconductor 2 to be oscillated is electrically connected to the piezoelectric vibrator 1 and the semiconductor 2 by the metal thin wire 9 by wire bonding through the metal lead 5 and the alloy layer 7 containing the solder 103 by welding. It constitutes an oscillator circuit. Further, the piezoelectric vibrator 1, the semiconductor 2, the metal lead 5, the metal thin wire 9
And is formed of resin 8.

As a second embodiment of the structure of the piezoelectric oscillator, as shown in FIGS. 2A and 2B, the piezoelectric vibrator FIG. 3 (1 in FIG. 2) and the piezoelectric vibrator 1 are electrically connected. The semiconductor 2 to be oscillated by the metal frame 3 is arranged in front and back relation with the metal frame 3, and the semiconductor 2 is fixed to the metal frame 3.
The tab 4 is pushed out toward the piezoelectric vibrator 1 and comes into contact with the piezoelectric vibrator 1 in parallel to ensure electrical insulation clearance between the piezoelectric vibrator 1 and the plurality of metal leads 5. This not only prevents electrical conduction between the piezoelectric vibrator 1 and the plurality of metal leads 5, but also prevents short circuits between the metal leads 5. With this structure, compared to arranging the piezoelectric vibrator and the semiconductor in the plane direction, it is approximately
2. Assembled in the thickness direction with the minimum total thickness of the components.

Further, the lead 6 of the piezoelectric vibrator 1 is attached to the metal lead 5 relating to electric oscillation and the solder 1 shown in FIG.
It is welded as an alloy layer 7 containing 03. Although the lead 6 does not necessarily require solder plating, the lead 6 is plated simultaneously with the inner side 104 when the solder plating 103 is performed on the plug body shown in FIG.
With the solder 103 still attached, the metal lead 5 is welded as an alloy layer containing the solder 103.

Finally, the whole including the piezoelectric vibrator 1, the semiconductor 2, the metal lead 5 and the tab 4 is molded by the heat resistant resin 8.

As described above, the assembly view 2 of the piezoelectric oscillator described in the embodiment is the essential point of assembly, and the soldering portion 106 of the vibrating piece 102, the case 105 and the plug body 3103 of the plug body FIG. The connection between the lead 6 of the vibrator and the metal lead 5 is configured to have a heat resistance of 260 ° C. or higher, including the components.

Further, the overall shape of the embodiment is an SOP type of an SMT-compatible flat package as shown in FIG. 1, but an application to the DIP type as a plug component is also given as an example.

The application of the flat package to the J-BEND lead type is also given as an example.

[0014]

The present invention is constructed as described above.
Therefore, the following effects can be obtained.
Piezoelectricity in the semi-melting temperature of tin-lead solder with a lead content of 90% or more
Secure the oscillator case and the piezoelectric vibrating piece to the inner lead.
Vacuum-bak the attached plug body and seal the solder.
For hermetically pressing the plug body into the case body
Has a low equivalent resistance and excellent high temperature aging characteristics.
It is possible to obtain a piezoelectric vibrator having high thermal properties.

[Brief description of drawings]

FIG. 1A is a perspective view showing an embodiment of a piezoelectric oscillator according to the present invention, and FIG. 1B is a main cross-sectional view of FIG. 1A (first embodiment).

FIG. 2 (a) is a main plan view (second section) of the assembly of FIG. 1 (a).
Example), (b) is a main cross-sectional view of FIG.
Example).

FIG. 3 is a sectional view showing an embodiment of a piezoelectric vibrator which is a component of the piezoelectric oscillator of the present invention.

FIG. 4 is a sectional view of a vibrating piece of the piezoelectric vibrator shown in FIG.

5 is a sectional view of the plug body of the piezoelectric vibrator shown in FIG.

FIG. 6 is a sectional view of a case body of the piezoelectric vibrator shown in FIG. 3;

FIG. 7 is a state diagram showing an embodiment of solder used for assembling the piezoelectric vibrator shown in FIG. 3;

FIG. 8 is a perspective view of an unconventional piezoelectric oscillator.

FIG. 9 is a main cross-sectional view of a conventional piezoelectric oscillator.

FIG. 10 is a cross-sectional view of a conventional piezoelectric vibrator.

[Explanation of reference numerals] 1 ... Piezoelectric vibrator showing an embodiment of the present invention 2 ... Semiconductor 3 ... Metal lead frame 4 ... Lead frame tab 5 ... Lead frame A plurality of leads of the piezoelectric vibrator, the lead terminal of the piezoelectric vibrator, the alloy layer containing the solder, the resin, the fine metal wire, the piezoelectric vibrator, the piezoelectric vibrator, and the like. Semiconductor 18 ... Resin 101 .. Electrode 102 .. Piezoelectric vibrating piece 103 .. Solder containing 90% or more lead 104 .. Inner lead of plug body 105. Case body 106 .. Soldering of piezoelectric vibrating piece. Part 107 · · · Pressure welding or welding tsuba

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 7

[Correction method] Change

[Correction content]

[Figure 7]

Claims (4)

[Claims] 1. A piezoelectric oscillator in which at least a piezoelectric oscillator, a semiconductor (IC) that electrically oscillates the piezoelectric oscillator, and a metal lead frame including a plurality of metal leads and tabs are resin-molded. The vibrator is also plated on the case body plug body with solder having a lead content of 90% or more, and the vibrating piece is soldered to the plug body with the solder, and the vibrating piece is soldered. A piezoelectric oscillator, wherein the plug body is hermetically pressed into the case body via the solder. 2. A lead terminal of the piezoelectric vibrator, which is re-plated with solder of the composition, and the metal lead frame are welded together with an alloy layer containing solder of the composition. The piezoelectric oscillator according to claim 1. 3. The piezoelectric vibrator and the semiconductor are arranged in front and back relation with respect to the metal frame, respectively, and the tab of the metal frame to which the semiconductor is fixed is arranged on the piezoelectric vibrator side. , Is pushed in parallel with the metal lead surface of the reciprocal number and comes into contact with the case body of the piezoelectric vibrator in parallel, and secures a clearance for electrical insulation between the case body of the piezoelectric vibrator and a plurality of metal leads. The piezoelectric oscillator according to claim 1, wherein: 4. The piezoelectric vibrator is configured such that the plug body to which the vibrating piece is soldered and the case body are vacuum-baked within a semi-molten state temperature in a solder state diagram and press-fitted. The piezoelectric oscillator according to claim 1, which is characterized in that.