JPH09135146A - Vibrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the corrosion resistance of a conductor in a throughhole part by adopting a copper-nickel alloy with a chromium or titanium used for a bed material for a conductor on an inner face of the throughhole of a cover in 1st and 2nd connection sections. SOLUTION: An end of a lead electrode 11 is inserted into a throughhole 13 and extended to a side opposite to a root through a side of a vibration section 7 to form a connection section. Furthermore, the other end of the lead electrode forms a connection section at the root. Then the conductors 18 in throughholes 16, 17 formed to a cover 3 corresponding to the connection sections are connected to external electrodes 4, 5. The 1st and 2nd connection sections are in continuity with the 1st and 2nd external electrodes 4, 5 via the conductors 18 provided to the inner face of the throughholes 16, 17 of the 1st or 2nd covers 2, 3, and seal films are formed in the throughholes 16, 17 of the covers 2, 3 by using a copper nickel alloy while chromium or a titanium is used as a bed material by the vapor-deposition method or the sputtering method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crystal oscillator or the like used in various electronic devices.

[0002]

2. Description of the Related Art A conventional vibrator of this type includes a diaphragm and first and second covers that cover the front and back surfaces of the diaphragm and sandwich the outer peripheral portion of the diaphragm with the outer peripheral portion. The diaphragm has a tongue-shaped vibrating portion inside the sandwiched by the first and second covers, and excitation electrodes are formed on the front and back surfaces of the diaphragm.

Conventionally, the lead electrodes of the front and back excitation electrodes of the vibrating portion and the first and second external electrodes outside the first or second cover are connected to each other through the through holes of the first or second cover. This is done via a conductor formed of copper with chromium or titanium as a base.

[0004]

In the above-mentioned conventional example, since the through hole provided in the first or second cover is formed by the sandblast method, large irregularities are formed on the inner wall surface of the through hole, or the through hole is formed. The edge of the penetration side of was partially chipped. Further, the through hole provided in the first or second cover is sealed by a conductor formed of copper with chromium or titanium as a base by vapor deposition or sputtering. However, there is a problem that a conductor formed of copper with chromium or titanium as a base has poor corrosion resistance and causes leakage due to corrosion.

Therefore, the present invention aims to enhance the corrosion resistance of the conductor in the through-hole portion.

[0006]

In order to achieve this object, the present invention provides a vibrating plate and a first vibrating plate which covers the front and back surfaces of the vibrating plate and clamps the outer peripheral part of the vibrating plate at its outer peripheral part. , A second cover, and at least one of the first or second cover having first and second external electrodes provided on the side opposite to the diaphragm, the diaphragm being the first and second outer electrodes. Has a tongue-like vibrating part inside the sandwiching part by the cover of
Excitation electrodes are formed on the front and back surfaces of the vibrating section, and lead electrodes are drawn from the front and back excitation electrodes via the roots of the vibrating section. Form a first connection part, the other lead electrode forms a second connection part after penetrating to the one lead electrode side, and these first and second connection parts form the first or second The conductor is formed on the inner surface of the through hole of the cover by a copper-nickel alloy with chromium or titanium as a base.

According to the present invention, the corrosion resistance of the conductor in the through-hole portion can be increased, and a more reliable vibrator can be obtained.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is directed to a diaphragm and first and first diaphragms which cover the front and back surfaces of the diaphragm and sandwich the outer peripheral portion of the diaphragm with the outer peripheral portion thereof. A second cover, and at least one of the first and second covers provided with first and second external electrodes provided on the side opposite to the diaphragm, and the diaphragm includes the first and second covers. The holding part has a tongue-like vibrating part inside, and the excitation electrodes are formed on the front and back sides of this vibrating part. The lead electrode is pulled out, one of the front and back lead electrodes forms a first connection portion, and the other lead electrode forms a second connection portion after penetrating to the one lead electrode side. Chrome provided with the first and second connection portions on the inner surface of the through hole of the first or second cover In addition, it is electrically connected to the first and second external electrodes through a conductor formed of copper-nickel alloy with titanium as a base, and has an effect of enhancing the corrosion resistance of the conductor in the through hole portion. .

The invention according to claim 2 is a copper-nickel alloy of a conductor provided on the inner surface of a through hole, wherein the nickel content is 5 to 20%, and the nickel content is 5%.
If it is below, the corrosion resistance effect is small, and if it is 20% or more, the stress of the film becomes large. Therefore, by setting the nickel content to 5 to 20%, the action of preventing peeling due to the stress of the film while maintaining the corrosion resistance effect. Is to have.

According to the third aspect of the present invention, the conductor provided on the inner surface of the through hole is made of copper-nickel alloy and chromium or copper-nickel alloy and titanium, whereby the adhesion with the sealing film is improved. It is possible to improve the airtightness.

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 is a vibration plate having a plate thickness of 100.
It is composed of a crystal plate of μm. First and second covers 2 and 3 made of a quartz plate having a plate thickness of 400 μm are directly bonded to the front and back surfaces of the diaphragm 1. It should be noted that reference numerals 4 and 5 in FIG. 1 are external electrodes and are arranged on the diagonal line of the back surface of the second cover 3. The diaphragm 1 is shown in FIGS.
As shown in, a U-shaped kerf 6 is formed inside thereof,
As a result, the tongue-shaped vibrating portion 7 is formed. Excitation electrodes 8 and 9 are formed on the front and back surfaces of the vibrating portion 7,
The lead electrode 1 via the root portion 10 of each vibrating portion 7
1, 12 are pulled out. As shown in FIGS. 2 to 5, the end of the inner lead electrode 11 penetrates the diaphragm 1 by the through hole 13, and then passes through the side of the vibrating section 7 as shown in FIG. The connection portion 14 is formed by extending to the side. The lead electrode 12 forms a connection part 15 on the base part 10 side.

Then, the conductor 1 in the through holes 16 and 17 formed in the cover 3 corresponding to these connecting portions 14 and 15 is formed.
8 are connected to external electrodes 4 and 5, respectively. In addition, the first and second covers 2 and 3 have the outer peripheral portion of the front surface of the diaphragm 1,
Although the outer peripheral portion of the back surface is sandwiched and directly joined, it is joined at the outer peripheral portion of the kerf 6 of the diaphragm 1, and the lead electrode 11 is located laterally of the vibrating portion 7. The portion passing through is joined to the second cover 3 on the outside thereof.

In order to form the lead electrode 11 on the side of the vibrating portion 7 on the back surface side of the diaphragm 1 as described above, as is apparent from FIGS.
Increase the plate thickness only at the sandwiching part with the second covers 2 and 3,
The vibrating portion 7 and the portions where the lead electrodes 11 and 12 are formed are thinned by etching. FIG.
It clearly shows the diaphragm 1 after this etching step,
The back surface portion corresponding to the frame line 19 is thinned by etching. Further, the outer peripheral portion of the frame line 19 is a portion to be sandwiched and joined by the covers 2 and 3, and as is apparent from FIG. 4, the sandwiching width 20 on the longitudinal side of the diaphragm 1 is sandwiched in the short direction. It is wider than the width 21.

Since the lead electrode 11 is provided on the lateral side of the vibrating portion 7 as shown in FIG. 3, the vibrating portion 7 is naturally displaced to one side from the central portion of the vibrating plate 1.

The cut groove 6 in the root portion 10 has a semi-circular shape as shown in FIG. 4, whereby cracks are less likely to occur even when an excessive impact is applied.

Now, the characteristic part of this embodiment will be described. In the present embodiment, FIGS.
As shown in FIG. 7, the through holes 16 provided in the second cover 3,
Reference numeral 17 has a conical shape with a smaller diameter on the diaphragm 1 side (the side through which the sandblast is penetrated).

First, as an example, a conductor 18 is formed by depositing copper-nickel or copper-nickel and titanium on the inner surfaces of the through holes 16 and 17 with chromium or titanium as a base by vapor deposition or sputtering. Chromium or titanium is deposited in the range of several hundred to several thousand Å in order to strengthen the adhesive force between crystal and copper, and copper-nickel is deposited in the range of several thousand Å to several μm in order to establish conduction. Also, in order to strengthen the adhesive force with the sealing film to be formed later, several hundred to several thousand Å of chromium or titanium is attached.

Above the conductor 18, the through holes 16 and 17 are provided.
The upper part of the small diameter is sealed, and the connection parts 14,
15 is electrically connected to the lower part of the second cover 3 on the side opposite to the diaphragm 1.
The opening edges of the through holes 16 and 17 are widened.

In this state, the through holes 16 and 17 are formed so as to cover the conductor 18 portion which covers the upper small diameter portions of the through holes 16 and 17.
The sealing film 22 is formed by injecting solder into the inside 17. A good airtightness is ensured in the through holes 16 and 17 due to the sealing body formed by the conductor 18 and the sealing film 22.

Further, when the external electrodes 4 and 5 are formed by screen printing or the like with the sealing film 22 formed, the through holes 16 and 17 are as shown in FIGS. 1, 5, 6 and 7.
It slightly falls into the through holes 16 and 17. Since the external electrodes 4 and 5 also become a part of the sealing body, airtightness is further enhanced.

In the above embodiment, the conductor 18 is formed by depositing copper-nickel and chromium or copper-nickel and titanium by vapor deposition or sputtering, but as the conductor 18, the sealing film 22 is used. Although the adhesive strength is slightly weakened, practical airtightness can be ensured by using only the copper-nickel alloy.

[0022]

As described above, the present invention provides a diaphragm, first and second covers for covering the front and back surfaces of the diaphragm and sandwiching the outer periphery of the diaphragm with the outer periphery thereof. Of the first or second cover, the first and second external electrodes are provided on the opposite side of the diaphragm from the diaphragm, and the diaphragm is tongue inwardly of the holding portion by the first and second covers. It has a piece-shaped vibrating portion, and excitation electrodes are formed on the front and back surfaces of this vibrating portion, and lead electrodes are drawn from these front and back excitation electrodes through the root portion of the vibrating portion, respectively. One of the front and back lead electrodes forms a first connecting portion, the other lead electrode forms a second connecting portion after penetrating to the one lead electrode side, and these first and second lead electrodes are formed. The connecting portions are respectively provided through conductors provided on the inner surface of the through hole of the first or second cover. Note that the first and second external electrodes are electrically connected to each other, and a sealing film is formed in the through-hole of the cover by a vapor deposition method or a sputtering method with chromium or titanium as an underlayer by a copper-nickel alloy. When the conductor on the inner surface is a copper-nickel alloy, the corrosion resistance can be improved by the nickel oxide film as compared with the case where the conductor is formed of only copper. In addition, a more dense film can be formed by using a copper-nickel alloy than by using only copper, and the sealing performance becomes more reliable.

Further, the film formed of the copper-nickel alloy is thinner than that formed only of copper, because the alloy layer formed at the interface with the solder sealing film formed thereon is thinner, so that the film thickness is made thinner. It becomes possible.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a vibrator according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view for explaining a surface state of the diaphragm shown in FIG. 1;

FIG. 3 is an exploded perspective view for explaining a back surface state of the diaphragm shown in FIG. 1;

FIG. 4 is a top view of the diaphragm.

FIG. 5 is a diagram A- of a vibrator in which a cover is joined to the diaphragm of FIG. 4;
A sectional view

FIG. 6 is a cross-sectional view of a vibrator in which a cover is joined to the vibrating plate of FIG.
B sectional view

FIG. 7 is an enlarged cross-sectional view of the relevant part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vibration plate 2 Cover 3 Cover 4 External electrode 5 External electrode 6 U-shaped groove 7 Vibrating part 8 Excitation electrode 9 Excitation electrode 10 Root part 11 Lead electrode 12 Lead electrode 13 Through hole 14 Connection part 15 Connection part 16 Through hole 17 Through hole 18 Conductor 22 Sealing film

Claims (3)

[Claims] 1. A vibrating plate, first and second covers for covering the front and back surfaces of the vibrating plate and sandwiching the outer peripheral part of the vibrating plate with the outer peripheral part thereof, and the first or second cover. At least one of the first and second sides provided on the side opposite to the diaphragm.
A second external electrode is provided, and the vibrating plate has a tongue-shaped vibrating portion inside the holding portion by the first and second covers, and excitation electrodes are formed on the front and back surfaces of the vibrating portion. , Lead electrodes are drawn out from the front and back excitation electrodes via the roots of the vibrating portions, respectively, one of the front and back lead electrodes forms a first connection portion, and the other lead electrode is A second connecting portion is formed after penetrating on the side of the one lead electrode, and these first and second connecting portions are provided on the inner surface of the through hole of the first or second cover. A vibrator which is electrically connected to each of the first and second external electrodes via a conductor formed of a copper-nickel alloy. 2. The vibrator according to claim 1, wherein the conductor is a copper-nickel alloy provided on the inner surface of the through hole, and the content of nickel is 5 to 20%. 3. The vibrator according to claim 1, wherein the conductor provided on the inner surface of the through hole is made of copper-nickel alloy and chromium or copper-nickel and titanium.