JP2001313534A - Manufacturing method for capacitor incorporated piezoelectric resonator and lead terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a capacitor incorporated piezoelectric resonator by which a soldering process can be simplified while downsizing is compatible. SOLUTION: The manufacturing method for a capacitor incorporated piezoelectric resonator where a piezoelectric resonator element 6 and a capacitive element are soldered to 1st-3rd lead terminals, includes a process where solder film is formed for the 3rd lead terminal 3, a process where the piezoelectric resonator element 6 is soldered to the 1st and 2nd lead terminals 1, 2 and solder film is formed on a face of the 1st and 2nd lead terminals 1, 2 onto which the capacitive element is fitted, and a process where the capacitive element is inserted between the 1st, 2nd lead terminals 1, 2 and the 3rd lead terminal 3, and by re-melting the solder film, the capacitive element is joined to the 1st-3rd lead terminals.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric resonator with a built-in capacitor used as, for example, a piezoelectric oscillator. More specifically, the present invention relates to a lead-type piezoelectric resonator in which a plurality of lead terminals are joined to a piezoelectric resonance element and a capacitor element. The present invention relates to a method of manufacturing a piezoelectric resonator with a built-in capacitor and a lead terminal used in the method.

[0002]

2. Description of the Related Art Various types of leaded piezoelectric resonators having a combination of a piezoelectric resonator element and a capacitor element have been proposed (for example, Japanese Patent Laid-Open No. 7-1831).
No. 37, Japanese Utility Model Application No. 6-26318, Japanese Unexamined Patent Application Publication No.
106889, etc.).

FIG. 8 is a perspective view showing an example of this kind of piezoelectric resonator with a built-in capacitor. In the built-in capacitor piezoelectric resonator 101, a plate-shaped piezoelectric resonance element 102 and a plate-shaped capacitor element 103 are used. A lead terminal 104 having a U-shaped cup portion,
105 is attached. That is, the lead terminal 1
04 and 105 are cup portions 104a and 105a on one end side.
And the end portions of the piezoelectric resonance element 102 are inserted into the cup portions 104a and 105a.
No. 02 is joined to the lead terminals 104 and 105 by soldering. The plate-shaped capacitor element 103 is joined to the outer surfaces of the cup portions 104a and 105a. At the center of the main surface on the opposite side of the capacitor element 103, a third
Lead terminals 106 are joined.

After the lead terminals 104 to 106 are joined to the piezoelectric resonance component 101, a resin sheath is provided as shown by a two-dot chain line A. Conventionally, the methods shown in FIGS. 9 to 11 have been employed for joining the lead terminals 104 to 106. That is, as shown in FIG.
A structure in which 4-106 are integrated with the metal hoop 107 is prepared. The piezoelectric resonance element 102 is inserted between the cup portions 104a and 105a at the tips of the lead terminals 104 and 105. Thereafter, a soldering iron 107 having a surface to which molten solder is adhered is brought into contact with the inside of the cup portions 104a, 105a, and the piezoelectric resonance element 102 and the cup portions 104a, 105
a is soldered. Thus, the piezoelectric resonance element 1
02 is joined to the lead terminals 104 and 105.

[0005] Next, as shown in FIG.
4a and 105a are brought into contact with the soldering irons 108 and 108 having the molten solder attached to the tips thereof, so that the cup 10
Solder is supplied to the outer side surfaces of 4a and 105a.

Thereafter, the plate-like capacitor element 103 is held by the outer surfaces of the cup portions 104a and 105a to which the solder is attached and the lead terminals 106, and the solder attached by the reflow soldering method is re-melted. Then, the capacitor element 103 is joined (see FIG. 11). In FIG. 11, reference numerals 111 to 113 denote solders connecting the capacitor elements to the first to third lead terminals 104 to 106.

[0007]

SUMMARY OF THE INVENTION In the conventional manufacturing method,
When attaching the piezoelectric resonance element 102 and the capacitor element 103, a step of soldering the piezoelectric resonator 102 to the lead terminals using the soldering irons 107, 107, and using the soldering irons 108, 108 prior to the manufacture of the capacitor element. Therefore, a step of supplying solder to the outside of the cup portion and a step of soldering the capacitor element by reflow soldering after inserting the capacitor element are necessary, and the manufacturing process is complicated.

When the size of the piezoelectric resonator with a built-in capacitor is reduced, the outer surfaces of the U-shaped cup portions 104a and 105a become smaller. However, the cup portions 104a, 104
When the outer surface of 5a is small, when solder is supplied by a soldering iron, the solder tends to flow into the cup portions 104a and 105a. Therefore, it is necessary to reduce the cross-sectional area of the tip of the soldering iron, but as the cross-sectional area of the tip of the soldering iron decreases, the stability of the supply of the molten solder to the tip of the soldering iron increases. Be impaired. Therefore, the conventional manufacturing method has a limit in reducing the size of the piezoelectric resonator with a built-in capacitor.

The lead terminals 104 and 105 are U
The same problem occurs even when a lead terminal having a V-shaped or L-shaped tip is used although it has a letter-shaped cup portion.

An object of the present invention is to solve the above-mentioned drawbacks of the prior art, to simplify the manufacturing process, and to reduce the size of the piezoelectric resonator with a built-in capacitor even when the lead terminal and the piezoelectric resonance element and the piezoelectric resonator are used. An object of the present invention is to provide a method of manufacturing a capacitor built-in piezoelectric resonator that can stably and surely join a capacitor element, and a lead terminal used in the manufacturing method.

[0011]

According to a broad aspect of the present invention, a plate-like piezoelectric resonance element, first and second lead terminals joined to the piezoelectric resonance element, and first and second leads are provided. The plate-shaped capacitor element bonded to the surface of the terminal opposite to the side to which the piezoelectric resonance element is bonded is opposite to the side bonded to the first and second lead terminals of the capacitor element. A third lead terminal joined to the side surface, a method for manufacturing a capacitor-equipped piezoelectric resonator, comprising: a step of forming a solder film for joining a capacitor element to the third lead terminal; (1) soldering the second lead terminal and the piezoelectric resonance element, and forming a solder film on a surface of the first and second lead terminals to which the capacitor element is bonded; Second and third lead terminals And bonding the capacitor element to the first to third lead terminals by re-melting the solder film, to provide a method of manufacturing a piezoelectric resonator with a built-in capacitor. You.

In a specific aspect of the production method according to the present invention,
The first to third lead terminals have a round bar shape except for at least the capacitor junction, and the capacitor junction is flat.

According to still another specific aspect of the manufacturing method of the present invention, the capacitor element has a plate-shaped capacitor substrate having first and second main surfaces, and a first and a second substrate formed on the first main surface.
A second capacitor electrode, and a third capacitor formed substantially at the center of the second main surface and opposed to the first and second capacitor electrodes via a capacitor substrate.

In another specific aspect of the production method of the present invention,
When soldering and forming a solder film, a flux having a solid content of 20% by weight or more is used. In still another specific aspect of the manufacturing method according to the present invention, when re-melting the solder film and performing soldering, the solder liquidus temperature + 130 ° C.
A soldering iron adjusted to the above temperature is used.

The lead terminal according to the present invention is used in the manufacturing method of the present invention, and has a round bar shape.
Further, at least a portion to which the capacitor element is joined is a lead terminal having a flat plate shape.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

With reference to FIGS. 1 to 7, a method for manufacturing a piezoelectric resonator with a built-in capacitor according to an embodiment of the present invention will be described. In this embodiment, first, first to third lead terminals 1 to 3 shown in FIGS. 3 and 4 are prepared. One end of each of the first to third lead terminals 1 to 3 is connected to the band-shaped metal hoop 4. The first to third lead terminals 1 to 3 have a substantially round bar shape as a whole. However, L-shaped holding parts 1a and 2a are formed at the tips of the lead terminals 1 and 2 by crushing and bending the round bar. In this embodiment, the L-shaped holding portions 1a and 2a
Although formed in the vicinity, it does not have to reach the tips 1b and 2b. The lead terminals 1 to 3 are also squashed to form flat plate-like capacitor element mounting portions 1c and 2c.
c, 3a are formed.

Although the capacitor element mounting portions 1c and 2c of the lead terminals 1 and 2 are located on the same plane, the capacitor element mounting portion 3a of the third lead terminal 3 has the capacitor element mounting portions 1c and 2c. Are formed in a plane different from that in FIG. This is to secure a space for inserting a capacitor element to be described later between the capacitor element mounting portions 1c and 2c of the lead terminals 1 and 2 and the capacitor element mounting portion 3a of the third lead terminal 3. Accordingly, the distance between the opposing surfaces of the capacitor element mounting portions 1c and 2c and the capacitor element mounting portion 3a is equal to the thickness of the inserted capacitor element.

The materials constituting the lead terminals 1 to 3 are not particularly limited, and an appropriate metal material such as aluminum or copper can be used. Next, as schematically shown in FIG. 5, the tip of the third lead terminal 3 is immersed in molten solder 4 maintained at a temperature of solder liquidus temperature + 30 ° C.
Pull up. In this manner, the preliminary solder is applied to the capacitor element mounting portion 3a of the lead terminal 3.

The solder liquidus temperature means a temperature at which the solder completely changes to a liquid state. When this preliminary solder is applied, not only the molten solder having a solder liquidus temperature of + 30 ° C. but also a molten solder having a solder liquidus temperature of about +20 to 70 ° C. can be used.

Next, a flux is applied to the inside of the L-shaped holding portions 1a and 2a at the tips of the first and second lead terminals 1 and 2. As the flux, an RMA type flux having a solid content of 20% by weight is suitably used.

Since the activity of the RMA type flux having a solid content of 20% by weight is high, the L-shaped holding portions 1d, 2d
Can be more reliably supplied to the surface opposite to the side to which the piezoelectric resonance element 6 is bonded.

After the flux is applied, the plate-shaped piezoelectric resonance element 6 is held between the L-shaped holding portions 1a and 2a as shown in the drawing viewed from the tip end of the lead terminal. FIG.
In the figure, reference numeral 7 denotes a solder film adhered by the process shown in FIG.

As shown in FIG. 2A, the piezoelectric resonator 6
Is a piezoelectric resonator using a thickness vertical mode in the present embodiment, and has a rectangular plate-shaped piezoelectric substrate 6a. Piezoelectric substrate 6a
The resonance electrodes 6b and 6c are formed so as to oppose the piezoelectric substrate 6a at the center of both main surfaces. The resonance electrodes 6b and 6c
Although it may be formed so as to reach the opposite main surface via the end surface, in the case of the present invention, by providing the L-shaped holding portions 1a, 2a on the tip side of the lead terminal, the resonance electrodes 6b,
Even if 6c is not formed so as to reach the main surface on the opposite side via the end face, a sufficient electrical and mechanical connection is possible. Therefore, one of the resonance electrodes comes into contact with each of the L-shaped holding portions 1a and 2a.

Thereafter, as shown in FIG. 7, the L-shaped holding portions 1a and 2a and the piezoelectric resonance element 6 are soldered by using soldering irons 8 and 9. Molten solder having a temperature equal to or higher than the solder liquidus temperature + 130 ° C. is bonded to the tips of the soldering irons 8 and 9 in advance. Then, the tips of the soldering irons 8 and 9 are brought into contact with the L-shaped holding portions 1a and 2a, so that the molten solder is supplied to the electrodes of the piezoelectric resonance element 6 and the L-shaped holding portions 1a and 2a. Is done. At this time, at the same time, the solder flows on the surfaces of the L-shaped holding portions 1a and 2a on the side opposite to the surface to which the piezoelectric resonance element 6 is joined.

Therefore, as is clear from FIG. 7, the solder films 10a and 10b are formed on the surfaces of the lead terminals 1 and 2 opposite to the surface to which the piezoelectric resonance element 6 is joined. Further, as described above, the lead terminal 3 is formed with the solder film 7 made of the preliminary solder.

Next, the capacitor element 12 is inserted into the gap between the first and second lead terminals 1 and 2 and the third lead terminal 3. As shown in FIG. 2B, the capacitor element 1
Reference numeral 2 denotes a rectangular plate-shaped capacitor substrate 12a made of dielectric ceramics, first and second capacitor electrodes 12b and 12c formed on the first main surface of the capacitor substrate, and formed on the second main surface. And a third capacitor electrode 12d. First and second capacitance electrodes 12b and 12c and third capacitance electrode 1
2d is opposed to the front and back via the capacitor substrate 12a. Further, a third capacitance electrode 12d is formed substantially at the center of the second main surface of the capacitor substrate 12a.

Thereafter, the total temperature is equal to the solder liquidus temperature +
The solder film is melted by a reflow method so that the temperature becomes 20 ° C. or more, and the capacitor element 12 is mounted. In this way, as shown in FIG. 1, the bonding between the piezoelectric resonance element 6, the capacitor element 12, and the first to third lead terminals 1 to 3 is achieved. In the above joining step, since a soldering iron is not required for soldering the capacitor element 12, the manufacturing process can be simplified.

The soldering irons 8 and 9 have lead terminals 1 and
Since the two L-shaped holders 1a and 2a are merely brought into contact with each other from the tip end side, the size of the piezoelectric resonator 1 can be reduced, and even if the dimensions of the L-shaped holders 1a and 2a are reduced, the piezoelectric resonator 1 can be reliably mounted. It is possible to supply a required amount of molten solder from the soldering irons 8 and 9, and it is difficult for excessive solder to be supplied onto the piezoelectric resonator 6. Therefore, miniaturization of the lead-containing capacitor built-in piezoelectric resonance component can be achieved.

In the manufacturing method of this embodiment, after the soldering step is completed as described above, a resin sheath is applied around a portion where the piezoelectric resonance element 6 and the capacitor element 12 are joined according to a known method. Thus, a piezo-resonant component with a built-in capacitor having leads can be obtained.

In the above embodiment, the energy trap type piezoelectric resonator using the thickness longitudinal mode is used. However, the piezoelectric resonator used in the present invention is not limited to this. An energy trap type piezoelectric resonator using the above vibration mode may be used. Although the first and second lead terminals have the capacitor element mounting portions formed in a flat plate shape as described above, round bar-shaped lead terminals that are not formed in a flat plate shape may be used. However, in order to surely form the solder film necessary for joining the capacitor element, it is desirable that the capacitor element mounting portion is formed in a flat plate shape as in the above embodiment.

In the above embodiment, the solder film was formed by immersing the third lead terminal in the molten solder in advance.
In the step of soldering the second lead terminal and the piezoelectric resonator, molten solder may be supplied to the third lead terminal using another soldering iron.

[0033]

According to the method of manufacturing a piezoelectric resonance component with a built-in capacitor according to the present invention, a solder film is formed on the capacitor element mounting portion of the third lead terminal, and the first and second lead terminals and the piezoelectric resonance element are connected. Since the solder film is formed on the surface of the first and second lead terminals to which the capacitor element is joined, the capacitor element is inserted between the first and second lead terminals and the third lead terminal, By remelting each of the solder films, the capacitor element can be joined to the first to third lead terminals.

Accordingly, in manufacturing the piezoelectric resonator with a built-in capacitor, the number of operations using a soldering iron can be reduced, and the manufacturing method of the piezoelectric resonator with a built-in capacitor can be simplified.

In addition, when the first and second lead terminals are soldered to the piezoelectric resonance element, if the solder is supplied from the leading end side of the lead terminals, the lead terminals of the first and second lead terminals are attached. It is possible to easily supply molten solder for a solder film for joining a capacitor element to a surface opposite to a surface on which the capacitor element is formed. Therefore, even if the dimensions of the first and second lead terminals to which the piezoelectric resonance element is attached become smaller, the molten solder on the side where the capacitor element is attached is also supplied at the same time. The molten solder can be supplied stably. It also contributes to downsizing of the piezoelectric resonator with a built-in capacitor.

When the first to third lead terminals are made of a substantially rod-shaped wire and at least the capacitor mounting portion is flattened by crushing, the capacitor mounting of the first to third lead terminals is performed. The molten solder can be reliably stored in the portion, and the solder film can be formed stably.

When the capacitor element has a capacitor substrate and first to third capacitance electrodes, and the third capacitance electrode is formed substantially at the center of the second main surface of the second capacitor substrate. Since the third lead terminal may be arranged substantially at the center between the first and second lead terminals, the capacitor element can be easily inserted, and the posture of the capacitor element when the capacitor element is inserted can be stabilized. Can enhance the character.

In the case of soldering, when an RMA type flux having a solid content concentration of 20% by weight or more is used in a portion of the lead terminal to be soldered, the soldering portion is effectively activated, and thereby the First, it is possible to more reliably supply the molten solder to the surface of the second lead terminal opposite to the side to which the piezoelectric resonance element is joined, and it is possible to more reliably form the solder film.

When a molten solder having a temperature equal to or higher than the solder liquidus temperature + 130 ° C. is supplied to the vicinity of the tips of the first and second lead terminals using a soldering iron, the temperature of the soldering iron is high. It is possible to stably supply the molten solder for attaching the capacitor element to the surface of the first and second lead terminals opposite to the surface to which the piezoelectric resonance element is joined. Therefore, the soldering of the capacitor element is performed more stably.

The lead terminal used in the method of manufacturing the piezoelectric resonance component with a built-in capacitor according to the present invention has a round bar shape with a substantially circular cross section, but at least the capacitor mounting portion is formed into a flat plate by crushing. Therefore, the molten solder can be easily stored using the flat plate-shaped capacitor mounting portion. Therefore, the capacitor element can be stably and easily joined by re-melting the solder film formed by solidification of the molten solder.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which first and second lead terminals are joined to a piezoelectric resonance element and a capacitor element is joined to first to third lead terminals in one embodiment of the present invention.

FIGS. 2A and 2B are perspective views showing a piezoelectric resonance element and a capacitor element.

FIG. 3 is a perspective view for explaining first to third lead terminals used in one embodiment of the present invention.

FIG. 4 is a plan view showing a state in which first to third lead terminals prepared in one embodiment of the present invention are joined to a metal hoop.

FIG. 5 is a perspective view showing a state in which the second lead terminal is immersed in molten solder in order to form a solder film on the second lead terminal.

FIG. 6 is a front view showing a state in which the piezoelectric resonance element is held by the holding portions of the first and second lead terminals according to the embodiment of the present invention, as viewed from the lead terminal tip side.

FIG. 7 is a partially cutaway perspective view for explaining a step of contacting a soldering iron to join the piezoelectric resonance element to first and second lead terminals in one embodiment of the present invention.

FIG. 8 is a perspective view for explaining an example of a conventional piezoelectric resonance component with a built-in capacitor.

FIG. 9 is a partially cutaway perspective view for explaining a step of soldering a piezoelectric resonance element inserted between a pair of lead terminals having a cup portion to a cup portion of the lead terminal in a conventional manufacturing method.

FIG. 10 is a partially cutaway perspective view for explaining a step of supplying solder to a cup portion of a lead terminal in a conventional method.

FIG. 11 is a schematic end view showing a state in which a capacitor element is joined to a lead terminal having a cup portion and a third lead terminal in the conventional method, as viewed from the terminal tip side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... 1st lead terminal 2 ... 2nd lead terminal 3 ... 3rd lead terminal 1a ... L-shaped holding part 2a ... L-shaped holding part 3a ... Capacitor mounting part 4 ... Molten solder 6 ... Piezoelectric resonance element 6a ... Piezoelectric Substrate 6b, 6c Resonant electrode 7 Solder film 8, 9 Soldering iron 10a, 10b Solder film 12 Capacitor element 12a Capacitor substrate 12b to 12d First to third capacitance electrodes

Claims (6)

[Claims] 1. A plate-shaped piezoelectric resonance element, first and second lead terminals joined to the piezoelectric resonance element, and a side of the first and second lead terminals to which the piezoelectric resonance element is joined. Is a plate-shaped capacitor element bonded to the opposite surface, and a third lead bonded to the surface of the capacitor element opposite to the side bonded to the first and second lead terminals. A method of manufacturing a piezoelectric resonator with a built-in capacitor, comprising: a step of forming a solder film for joining a capacitor element to the third lead terminal; and a step of forming a piezoelectric resonance between the first and second lead terminals. Soldering the element and forming a solder film on the surface of the first and second lead terminals to which the capacitor element is joined; and connecting the capacitor element to the first and second lead terminals and the third lead. Insert between the terminal and the solder film And bonding the capacitor element to the first to third lead terminals by re-melting the piezoelectric element. 2. The built-in capacitor according to claim 1, wherein the first to third lead terminals have a round bar shape except for at least the capacitor junction, and the capacitor junction has a flat plate shape. A method for manufacturing a piezoelectric resonator. 3. The capacitor element according to claim 1, wherein the capacitor element has a plate-shaped first and second main surface, a first and second capacitor electrode formed on the first main surface, and a second main electrode. The piezoelectric resonator with a built-in capacitor according to claim 1 or 2, wherein the third capacitor is formed substantially at the center of the surface and has a first and a second capacitor electrode and a third capacitor facing the front and back via the capacitor substrate. Manufacturing method. 4. In the step of soldering and forming a solder film,
The method for producing a piezoelectric resonator with a built-in capacitor according to any one of claims 1 to 3, wherein a flux having a solid content of 20% by weight or more is used. 5. A soldering iron adjusted to a temperature equal to or higher than a liquidus temperature of the solder + 130 ° C. when the solder film is remelted and soldered.
The method for manufacturing a piezoelectric resonator with a built-in capacitor according to any one of the above. 6. A lead terminal used in the method for manufacturing a piezoelectric resonator with a built-in capacitor according to claim 1, wherein the lead terminal has a round bar shape, and at least a portion to which the capacitor element is joined has a flat plate shape. Lead terminals.