JPH1141059A - Crystal oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crystal oscillator with higher reliability which is not affected by solder balls resulting from solder swept out to a gap between a crystal chip and a base and hardened. SOLUTION: This crystal oscillator is provided with a crystal chip 1 formed with excitation electrodes; a base 4 where lead terminals 5, 6 are implanted via glass G air-tightly with insulation and where outer leads 51, 61 and inner leads 52, 62 are formed; and a cap formed by applying air-tight sealing to an area including the crystal chip and the inner leads of the base. Further, the crystal chip 1 is placed upright between the inner leads of the lead terminals and the excitation electrodes, and the inner leads are connected by solder H electrically and mechanically. At this time solder bonding films 24, 34 are formed to the bottom side of the crystal chip 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crystal resonator incorporated in an electronic device and the like, and more particularly to an electrode shape of a crystal resonator which is disposed upright between lead terminals implanted in a base.

[0002]

2. Description of the Related Art A conventional general crystal unit will be described with reference to the drawings, taking a tuning fork type crystal unit as an example. FIG. 7 is an exploded perspective view showing a conventional tuning-fork type crystal resonator. The tuning-fork type crystal blank 1 includes tuning-fork legs 11 and 12 as resonance parts, and a base 13 as a supporting part that supports the resonance parts.
The first excitation electrode 2 is formed on the front and back surfaces of the leg 11 and the inner and outer surfaces of the leg 12 and is commonly connected to each other.
Are formed on the inner and outer surfaces of the leg portion 11 and the front and back surfaces of the leg portion 12 and are commonly connected. In the cylindrical metal base 4, the lead terminals 5, 6 are hermetically and insulated and implanted through the glass G, and constitute outer lead portions 51, 61 and inner lead portions 52, 62. Then, cream solder H is applied to the inner lead portions 52 and 62, and the tuning fork-type crystal blank 1 is inserted between the inner lead portions 52 and 62 to be placed upright. Then, the solder is cured. In addition to being mechanically joined, the excitation electrode and the lead terminal were electrically connected. Then, the metal base portion on the side of the inner lead on which the tuning fork type crystal piece is mounted is hermetically sealed with a metal cap (not shown) to produce a final tuning fork type crystal resonator.

[0003]

However, when a tuning fork-type crystal piece is inserted between the inner leads to which the cream solder has been applied, a part of the cream solder applied to the inner lead is partially replaced by the tuning fork-type crystal. In some cases, the bottom of the base of the piece was scraped off to the glass portion of the base in the downward direction, and remained in the gap between the tuning-fork type quartz piece and the glass portion of the base.
In particular, as shown in FIG. 8, when a base having an upper surface formed of glass G is used, a portion near the lead terminals 5 and 6 of the glass G is raised due to the effect of surface tension. Even if the piece 1 is mounted in close contact with the glass G of the base, a gap S is formed.
The cream solder H is scraped out and easily intervenes. Since the solder is not bonded to the crystal base portion, the remaining cream solder is hardened later to form a solder ball, comes out of the gap portion after commercialization, and adheres to the tuning fork type quartz piece, etc. This had an adverse effect on the characteristics of the crystal unit.

SUMMARY OF THE INVENTION An object of the present invention is to provide a more reliable crystal resonator which is not adversely affected by a solder ball formed by curing the solder interposed between the crystal piece and the base by being scraped out to the gap between the crystal piece and the base. The purpose is to do.

[0005]

According to the present invention, there is provided a crystal resonator comprising:
In order to solve the above problem, as set forth in claim 1, a crystal blank on which an excitation electrode is formed and a plurality of lead terminals are hermetically and insulated and implanted via a glass material, and an outer lead portion is provided. And a base that constitutes an inner lead portion, and a cap that hermetically seals a region including the crystal blank and the inner lead portion of the base, wherein the crystal blank is disposed between the inner lead portions of the lead terminals. In a crystal resonator in which the excitation electrode and the inner lead portion are electrically and mechanically connected by solder,
A solder bonding film is formed on the bottom surface of the crystal blank.

According to a second aspect of the present invention, a crystal blank having at least two legs and having a first excitation electrode and a second excitation electrode formed thereon, and a plurality of lead terminals are provided. A base that is hermetically sealed and insulated through a glass material and constitutes an outer lead portion and an inner lead portion,
A cap that hermetically seals the region including the inner lead portion of the crystal piece and the base is provided, and the crystal piece is erected between the inner lead portions of the lead terminals,
In a quartz oscillator in which the excitation electrode and the inner lead portion are electrically and mechanically connected by solder, a solder bonding film is formed on a bottom surface of the quartz piece.

With the above structure, even if the solder is scraped and intervened into the gap between the crystal piece and the base, the solder adheres to the solder bonding film formed on the bottom surface of the crystal piece and hardens. As a result, no solder ball is formed, and the solder ball does not come out of the gap, so that adverse effects such as the solder ball adhesion to the crystal piece are eliminated, and problems such as non-oscillation and frequency fluctuation are prevented.

Further, as set forth in claim 3, the solder bonding film may be constituted by an extraction electrode extended from the excitation electrode to both ends of the bottom surface of the crystal blank.

With the above structure, even if the solder is scraped and intervened into the gap between the crystal piece and the base, the solder is drawn out of one of the extraction electrodes formed at both ends of the bottom face of the crystal piece. It adheres to and hardens. As a result, no solder ball is formed and the solder ball does not come out of the gap, so that the solder ball does not adhere to the crystal blank, thereby preventing problems such as non-oscillation and frequency fluctuation. Since the extraction electrode can be formed integrally when the excitation electrode is formed, it can be manufactured very efficiently without a post-process.

The solder bonding film may be constituted by an independent electrode which is not electrically connected to the excitation electrode and is formed on a bottom surface of the crystal blank. .

According to the above configuration, even if the solder is scraped and interposed in the gap between the crystal piece and the base, the solder adheres to the independent electrode formed at the center of the bottom surface of the crystal piece and hardens. As a result, no solder ball is formed and the solder ball does not come out of the gap, so that the solder ball does not adhere to the crystal blank, thereby preventing problems such as non-oscillation and frequency fluctuation. Since the independent electrode is independent of the excitation electrode without being electrically connected thereto, the area of the excitation electrode does not change. Therefore, a desired oscillation frequency can be obtained without changing the set capacitance (C ₀ ). Also, when this independent electrode is formed at the same time as the formation of the excitation electrode, it can be manufactured extremely efficiently without a post-process. When the independent electrode is formed in a separate step, a material different from that of the excitation electrode can be used for the independent electrode. Therefore, a metal material (for example, Au) having better wettability and less oxidization is used. In addition, it is possible to improve the adhesion of the solder and further prevent the solder from peeling after curing.

[0012]

Next, a first embodiment of the present invention will be described with reference to the drawings, taking a tuning fork type crystal resonator as an example. FIG. 1 is an exploded perspective view of a tuning-fork type crystal resonator according to a first embodiment of the present invention. FIG. 2 is a perspective plan view showing a deposition mask for forming electrodes in the first embodiment, and FIG. 3 is a perspective plan view showing a spacer for forming electrodes in the first embodiment. still,
The same parts as those in the related art are denoted by the same reference numerals.

The tuning-fork type crystal blank 1 includes tuning fork legs 11 and 12 as a resonance portion, and a base 13 as a supporting portion for supporting and supporting the resonance portion. An excitation electrode 2 and a second excitation electrode 3 are formed.

The first excitation electrode 2 has an electrode 21 (rear surface not shown) on the front and back surfaces of the leg portion 11 and an electrode 22 (inner surface not shown) on the inner and outer surfaces of the leg portion 12. These electrodes are connected to the extraction electrodes 2 provided on the front and back surfaces of the base 13.
3 (the back surface is not shown), an extraction electrode 24 provided on one end of the bottom surface of the base 13, and an extraction electrode 25 provided on the leg 12.

The second excitation electrode 3 has an electrode 31 (rear surface not shown) on the front and back surfaces of the leg portion 12 and an electrode 32 (outer surface not shown) on the inner and outer surfaces of the leg portion 11. These electrodes are connected to extraction electrodes 3 provided on the front and back surfaces of the base 13.
3 (the back surface is not shown), an extraction electrode 34 provided on the other end of the bottom surface of the base 13, and an extraction electrode 35 provided on the leg 11.

As a method for providing these electrode structures, the tuning-fork type quartz piece is accommodated in a metal spacer 7 as shown in FIG. 3, and a metal evaporation mask 8 as shown in FIG.
Are used to sandwich the front and back surfaces of the tuning-fork type quartz piece 1 with the vapor deposition masks facing each other. For example, chromium,
Electrode materials such as silver and gold were attached. 2 and 3
A dotted line indicates a tuning-fork type crystal piece sandwiched between evaporation masks.

As described above, the cylindrical metal base 4 on which the tuning fork type quartz piece having the electrodes formed thereon is mounted is connected to the lead terminals 5, 5.
6 are hermetically and insulated through the glass G, and the outer lead portions 51 and 61 and the inner lead portions 52 and 62 are provided.
Is composed.

The inner lead portions 52, 62
To the inner lead portion 5
After inserting the tuning-fork type quartz piece 1 between 2 and 62 and arranging it upright, the solder is hardened and mechanically joined, and the excitation electrode and the lead terminal are electrically connected. Then, the metal base portion on the side of the inner lead portion on which the tuning fork crystal pieces are mounted is hermetically sealed with a metal cap (not shown) to complete the tuning fork crystal resonator.

In the first embodiment of the present invention, the extraction electrodes 24,
Since the layer 34 also functions as a solder bonding film, the solder that has been scraped out and interposed between the tuning-fork type crystal blank 1 and the base 4 can be adhered, and the solder peeling after curing can be prevented.

Next, a second embodiment of the present invention will be described with reference to the drawings, taking a tuning-fork type quartz resonator as an example. FIG. 4 is an exploded perspective view of a tuning-fork type crystal resonator according to a second embodiment of the present invention. FIG. 5 is a perspective plan view showing a deposition mask for forming electrodes in the second embodiment, and FIG. 6 is a perspective plan view showing a spacer for forming electrodes in the second embodiment.
The same parts as in the conventional embodiment and the first embodiment are denoted by the same reference numerals.

The tuning-fork type crystal blank 1 includes tuning fork legs 11 and 12 as a resonance portion, and a base 13 as a supporting portion for supporting and supporting the resonance portion. An excitation electrode 2 and a second excitation electrode 3 are formed. In addition, an independent electrode 9 that is not electrically connected to the first excitation electrode 2 and the second excitation electrode 3 is formed at the center of the bottom surface of the base 13.

The first excitation electrode 2 has an electrode 21 (rear surface not shown) on the front and back surfaces of the leg portion 11 and an electrode 22 (inner surface not shown) on the inner and outer surfaces of the leg portion 12. These electrodes are connected to the extraction electrodes 2 provided on the front and back surfaces of the base 13.
3 (the back surface is not shown), and are commonly connected via an extraction electrode 25 provided on the leg 12.

The second excitation electrode 3 has an electrode 31 (rear surface not shown) on the front and back surfaces of the leg portion 12 and an electrode 32 (outer surface not shown) on the inner and outer surfaces of the leg portion 11. These electrodes are connected to extraction electrodes 3 provided on the front and back surfaces of the base 13.
3 (the back surface is not shown), and are commonly connected via an extraction electrode 35 provided on the leg 11.

As a method of providing these electrode structures, as shown in FIG. 6, the tuning fork type quartz piece is accommodated in a metal spacer 71, and a metal evaporation mask 81 as shown in FIG.
Are used to sandwich the front and back surfaces of the tuning-fork type quartz piece 1 with the vapor deposition masks facing each other. For example, chromium,
Electrode materials such as silver and gold were attached. 5 and 6
A dotted line indicates a tuning-fork type crystal piece sandwiched between evaporation masks.

As described above, the tuning fork type crystal blank having the electrodes formed thereon is coated with cream solder H on the inner lead portions 52 and 62 of the base 4, and the In the meantime, after inserting the tuning fork type crystal blank 1 and arranging it upright, the solder is hardened and mechanically joined, and the excitation electrode and the lead terminal are electrically connected. Then, the metal base portion on the inner lead portion side on which the tuning fork type crystal pieces are mounted is hermetically sealed with a metal cap to complete the tuning fork type crystal resonator.

In the second embodiment of the present invention, the independent electrode 9 formed at the center of the bottom surface of the tuning-fork type quartz piece 1 is
Since it functions as a solder bonding film, the solder that is scraped out into the gap between the tuning-fork type quartz piece 1 and the base 4 and adheres to the interposed part can be prevented from being peeled after curing.

In the first and second embodiments, the solder bonding film is formed of an electrode, but may be formed of a film of an insulating material which is easily bonded to solder. In addition, an extraction electrode or an independent electrode serving as a solder bonding film may be formed of a metal material (for example,
Au, etc.). With this configuration, it is possible to improve the adhesiveness of the solder and further prevent the solder from peeling after curing. When the solder bonding film is made of a material different from that of the excitation electrode, it is necessary to form the solder bonding film by a process different from the process of forming the excitation electrode. However, as in the case of the extraction electrode and the independent electrode shown in the first and second embodiments, the formation of the solder bonding film using the same electrode material as the excitation electrode is not performed simultaneously with the excitation electrode using a vapor deposition mask. Since it can be formed, it can be said that it is more preferable in that it can be manufactured extremely efficiently.

Further, in the first and second embodiments, a tuning fork type crystal resonator using a tuning fork type crystal piece is taken as an example.
Needless to say, as shown in (a) and (b), the present invention can also be applied to a crystal resonator using a rectangular crystal piece.

[0029]

According to the first and second aspects of the present invention, even if the solder is scraped off and interposed in the gap between the crystal piece and the base, the cured solder remains on the solder bonding film formed on the bottom surface of the crystal piece. Attaches to and cures. As a result, no solder ball is formed and the solder ball does not come out of the gap portion, so that the solder ball does not adhere to the crystal blank, thereby preventing problems such as non-oscillation and frequency fluctuation. A high crystal oscillator can be provided.

According to the third aspect of the present invention, even when the solder is scraped and intervened in the gap between the crystal piece and the base, the solder ball does not come out of the gap, so that the solder ball adheres to the crystal piece. In addition to providing a more reliable crystal unit that prevents defects such as non-oscillation and frequency fluctuation, the electrode that is the solder bonding film can be formed integrally with the excitation electrode, so that the manufacturing efficiency is extremely high A crystal resonator can be provided.

According to the present invention, even if the solder is scraped and intervened in the gap between the crystal piece and the base, the solder ball does not come out of the gap, so that the solder ball adheres to the crystal piece. This prevents problems such as non-oscillation and frequency fluctuation. Since the independent electrode is independent of the excitation electrode without being electrically connected thereto, the desired oscillation frequency can be obtained without changing the excitation electrode area and the set capacitance (C ₀ ). Etc.
In addition to providing a more reliable crystal unit, the electrode that is the solder bonding film can be formed simultaneously with the excitation electrode.
A crystal oscillator with extremely high manufacturing efficiency can be provided.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a tuning-fork type crystal resonator according to a first embodiment of the present invention.

FIG. 2 is a perspective plan view showing a deposition mask for forming a first electrode of the present invention.

FIG. 3 is a perspective plan view showing a first electrode forming spacer of the present invention.

FIG. 4 is an exploded perspective view of a tuning-fork type crystal resonator according to a second embodiment of the present invention.

FIG. 5 is a perspective plan view showing a deposition mask for forming a second electrode according to the present invention.

FIG. 6 is a perspective plan view showing a spacer for forming a second electrode of the present invention.

FIG. 7 is an exploded perspective view showing a conventional tuning-fork type crystal resonator.

FIG. 8 is a sectional view of a base portion of a conventional tuning-fork type quartz resonator.

FIG. 9 is a perspective view of a crystal blank showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tuning fork type crystal piece 2 ... 1st excitation electrode 3 ... 1st excitation electrode 4 ... Metal base 5, 6 ... Lead terminal 7 ... Spacer 8 ... Vapor deposition Mask 9: Independent electrode 10: Quartz piece

Claims (4)

[Claims] 1. A base having an excitation electrode formed thereon and a plurality of lead terminals hermetically and insulatedly implanted through a glass material to form an outer lead portion and an inner lead portion. A cap that hermetically seals a region including the crystal piece and the inner lead portion of the base, and the crystal piece is placed upright between the inner lead portions of the lead terminals, and the excitation electrode and the inner lead are provided. A quartz oscillator, wherein a portion is electrically and mechanically connected to each other by solder, wherein a solder bonding film is formed on a bottom surface of the quartz piece. 2. A crystal blank having at least two legs and formed with a first excitation electrode and a second excitation electrode, and a plurality of lead terminals are hermetically and insulated through a glass material. A base formed by implanting and forming an outer lead portion and an inner lead portion; and a cap hermetically sealing a region including the crystal blank and the inner lead portion of the base. In a crystal resonator in which the crystal piece is placed upright between lead portions and the excitation electrode and the inner lead portion are electrically and mechanically connected by solder, a solder bonding film is formed on the bottom surface of the crystal piece. A quartz oscillator characterized by being formed. 3. The quartz vibrating device according to claim 1, wherein the solder bonding film is formed of an extraction electrode that extends from the excitation electrode to both ends of the bottom surface of the crystal piece. Child. 4. The solder bonding film according to claim 1, wherein said solder bonding film is not electrically connected to said excitation electrode and is constituted by an independent electrode formed on a bottom surface of said crystal blank. 2. The crystal resonator according to 2.