JP3107414B2 - Quartz crystal resonator and sealing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support for supporting a crystal blank.
The present invention relates to a configuration of a crystal resonator in which a cover for covering the crystal piece is fixed to a member, and a method of sealing the crystal resonator.

[0002]

2. Description of the Related Art Conventionally, a method for sealing a container for accommodating a crystal blank is a method of press-fitting a gap between the support member for supporting and fixing the crystal blank and the lid with a solder interposed therebetween, and a method of sealing the support member and the lid. There are a method of welding, a method of cold-pressing with oxygen-free copper interposed in the gap between the support member and the lid, and a method of joining the support member and the lid with low-melting glass. Hereinafter, a conventional main sealing method will be described with reference to the drawings.

FIG. 5 is a view for explaining a press-fitting method in which solder is interposed, FIG. 6 is a view for explaining a resistance welding method, and FIG. 7 is a view for explaining a low melting point glass joining method. FIG. 3 is a cross-sectional view showing a state where the crystal units are housed in a container. Hereinafter , a conventional method of sealing a crystal unit will be described with reference to FIGS. 5, 6, and 7. FIG.

FIG. 5 shows a sealing method mainly applied to a tuning fork type vibrator. The crystal blank 13 is fixed to the support member 11 with the bonding material 17. Thereafter, the lid 15 made of a metal material forming the lid solder film 15a made of solder, performing encapsulation was pressed in a vacuum to a supporting member 11 forming the support member solder film 11a made of solder. Therefore, solder, which is a low melting point metal, is interposed between the support member 11 and the lid 15.

FIG. 6 shows a sealing method mainly applied to a high-frequency crystal resonator. The crystal blank 19 is supported and fixed to the support member 21. Thereafter, a support member flange 21a of the support member 21;
The upper electrode 2 is connected to the lid flange 23a of the lid 23 made of a metal material.
5 and the lower electrode 27, and the upper electrode 25 and the lower electrode 27 are energized in an inert gas atmosphere so that
Performing sealing by welding the 1a and the lid flange portion 23a.

FIG. 7 shows a method of sealing using low-melting glass, in which a quartz piece is housed in a flat container. The crystal blank 33 is fixed on the extraction electrode 39 of the support member 29 with the bonding material 31. Thereafter, the low melting point glass 37 to the lid 35 and the support member 29, an inert gas atmosphere Chua Rui do sealing by joining in a vacuum.

[0007]

In recent years, most electronic devices using a quartz oscillator use an automatic insertion machine when electronic components including the quartz oscillator are mounted on a substrate. In this case, after the electronic component is inserted into the substrate on which the solder is formed, the solder is melted in a reflow furnace, and the electronic component is soldered to the substrate.

[0008] From the ease of automatic insertion of miniaturization and the electronic component cases, electronic devices mounted using the automatic inserting machine, the surface mount device (hereinafter which is thinner and smaller as electronic parts SMD) is required. Furthermore,
For passage equipped with the substrate an electronic component into a reflow furnace
The temperature at which the solder melts during reflow, for example, 26
The SMD is required to have a performance that can withstand 0 ° C. for 30 seconds.

However, it is impossible for the present quartz oscillator to have the following requirements in order to achieve the above requirements of thinning, miniaturization, and high heat resistance.

[0010] A supporting member for supporting and fixing the crystal piece and a lid,
In the method described with reference to FIG. 5 in which press-fitting is performed with solder interposed, the size of the crystal unit can be reduced. However, there is a disadvantage that the solder, which is a low melting point metal, is interposed between the support member and the lid, so that it cannot withstand the reflow temperature of 260 ° C.

In the resistance welding method described with reference to FIG. 6, there is no problem with heat resistance, but since the support member and the lid are welded,
The support member and the lid have a support member flange and a lid flange, respectively. Therefore, the size of the crystal resonator becomes large in the region of the support member flange and the lid flange, and it is difficult to reduce the size and thickness of the crystal resonator.

Although not shown, the cold welding method is shown in FIG.
Is sealed by a method substantially similar to the resistance welding method described with reference to FIG. That is, the oxygen-free copper is formed on both the support member flange portion and the lid flange portion, then seals to mechanically crimp joining the oxygen-free copper to each other. Therefore, in this cold welding method, similarly to the resistance welding method, since the supporting member and the lid are provided with the supporting member flange and the lid flange, respectively, it is difficult to reduce the size of the crystal unit.

In the sealing method using the low-melting glass shown in FIG. 7, the melting temperature of the low-melting glass is as high as about 450 ° C. An increase in gas pressure in the vibrator vessel occurs,
Further, there is a problem that the electrode material formed on the crystal blank is deteriorated and the characteristics of the crystal resonator are deteriorated.

An object of the present invention is to solve the above-mentioned problems, to seal a support member for supporting and fixing a crystal blank and a lid at a low temperature, and to further reduce the size and thickness of the crystal unit and the sealing. The present invention provides a stopping method and thereby realizes the SMD of the crystal unit.

[0015]

The present invention achieves the above objects.
In order to achieve this, a crystal unit with the following configuration and its sealing method
Act and provide.

A quartz resonator according to the present invention has a support member for supporting a crystal blank, and an outer peripheral portion of the support member.
A lid covering the crystal piece and fixed so as to partially expose, Knitting provided on the outer periphery of the exposed portion and the lid of the outer periphery of the <br/> support member
And a sealing film made of Kel . Consisting of the above nickel
Forming an adhesion improving film made of chromium under the sealing film
Good. Furthermore, silicon oxide or
Is preferable to form a protective film made of aluminum oxide.

In the method for sealing a crystal resonator according to the present invention, a supporting member for supporting a crystal blank is provided with a part of the outer periphery of the supporting member.
The crystal vibrator press-fits the lid that covers the crystal blank so that the
The rotor is placed in a vacuum device, and then the vacuum device is cleaned.
Evacuate to a predetermined vacuum level and then respond to the vacuum device
The exposed portion of the outer periphery of the support member by the vacuum coating forming method
A sealing film is formed on the outer periphery of the lid . Nicking the sealing film
It is desirable to form with Kel. The above vacuum device is
Deposition equipment, sputtering equipment, plasma CVD equipment, etc.
Or an ion plating apparatus,
The formation method is vacuum evaporation, sputtering, plasma C
VD method or ion plating method
No. Furthermore, in the above-mentioned vacuum device, the above-mentioned
Forming the sealing film while rotating the crystal oscillator
desirable.

[0018]

BRIEF DESCRIPTION OF THE PREFERRED embodiment of the present invention with reference to the drawings. Figure 1 is a sectional view showing the structure of an embodiment of a crystal resonator according to the present invention. This crystal resonator has a support member 41 that supports a crystal blank 45 using a bonding material 47, and a part of the outer periphery of the support member 41 is exposed to the support member 41.
A lid 43 which covers the crystal piece 45 by Uni fixed, provided on the outer periphery of the exposed portion and the lid 43 of the outer periphery of the support member 41 nickel
And a sealing film 49 made of. The sealing film 49 digits set in the outer peripheral portion of the support member 41 and the cover 43, the support member 4
1 and the lid 43 are sealed.

[0019] In this case, a crystal piece 45 fixed at the bonding material 47 to the support member 41, press-fitting the cover 43 made of a metallic material
To form a crystal unit. Thus, even if the lid 43 is pressed into the support member 41, the support member 41 and the lid 43
Since no low-melting-point metal such as solder exists between them, the container of the quartz oscillator is not hermetically sealed . Therefore, the gas passes through the inside and outside of the container of the quartz oscillator from the portion A on the outer peripheral portion where the support member 41 and the lid 43 are fixed.

After that, the quartz oscillator is arranged in a vacuum device, and for example, nickel (Ni) is formed by a vacuum deposition method. The Ni melted in the vacuum device is scattered in a fine particle state into the crystal oscillator container, and the support member 41 and the cover 4
The sealing film 49 is formed on the outer peripheral portion of the support member 41 and the lid 43 in a thick or thin film state. Since the supporting member 41 and the lid 43 are cylindrical, the gas passing through the portion A at the outer peripheral portion through which the gas passes is blocked by the sealing film 49, and the sealing between the supporting member 41 and the lid 43 can be performed. Become. Conventionally, the support member 41 and the lid 43 are sealed with solder therebetween, but in the present invention, a material having a high melting point is used .
Since the sealing film 49 is formed of certain nickel, a crystal oscillator having good heat resistance can be obtained.

[0021] The thickness of the sealing film 49, for serving as a fixation of the sealing contact and support member 41 and the cover 43, membrane tens of microns from the lowest few microns to maintain the mechanical strength of the completed Thickness is required.

The sealing film 49 is made of nickel ( N
i ) is preferable, but materials such as titanium nitride (TiN), titanium carbide (TiC), silicon oxide (SiO2), aluminum oxide (Al2 O3), and diamond-like carbon can be used. Materials other than the above can be used as long as the properties can be maintained. That is, not only a single metal film but also an alloy film, a nitride film, a carbide film, and an oxide film can be used as the sealing film 49.

The sealing film 4 is formed between the support member 41 and the lid 43.
If the adhesion of 9 is poor, an adhesion improving film is formed below the sealing film 49. When the sealing film 49 is made of nickel ( Ni ) ,
Chromium as the adhesion enhancing film to be formed on the lower layer (Cr)
Is used, the adhesion of the sealing film 49 is improved. As described above, in order to improve the adhesion of the sealing film 49, a base film of the sealing film 49 can be formed.

Further, a protective film 51 may be further formed on the sealing film 49 as shown in FIG. For example,
When the sealing film 49 is made of nickel ( Ni ) , silicon oxide ( SiO ₂ ) or aluminum oxide ( A
If l ₂ O ₃ ) is formed to have a two-layer structure, the protective film 51 can improve the heat resistance and further prevent solder from being attached to unnecessary portions of the crystal unit during surface mounting. .

As described above, the sealing film 49 can be formed not only of one layer but also of a plurality of different materials to improve the performance of the crystal unit.

[0026] Figure 2 of the present invention, to the conventional illustrated FIG 6
It is obtained by application of the improvement of the high frequency crystal oscillator. FIG.
In a manner similar to the structure described with reference to FIG. 1, a part of the outer periphery of the support member is
The cover 57 covering the crystal piece 55 is press-fitted and fixed ,
At the exposed portion of the outer periphery of the support member 53 and the outer periphery of the lid 57 ,
A sealing film 59 made of Ni is provided. With this sealing film 59, the support member 53 and the lid 57 are sealed. Therefore, the brim portion that is required in the conventional resistance welding method or cold pressure welding method is not required.

Also in this case , the crystal piece 55 is supported by the support member 53, and the lid 57 is pressed into the support member 53. At this time, even if the lid 57 is pressed into the support member 53, the support member 53 and the lid 5
Since no solder is interposed between 7 and 7, gas passes through the inside and outside of the container of the quartz oscillator. Thereafter, as described with reference to FIG. 1, a sealing film 59 made of Ni is formed using a vacuum device, and the support member 53 and the lid 57 are sealed.

Therefore, unlike the conventional cold pressure welding method and the resistance welding method, the present invention eliminates the need for the brim portion conventionally required for sealing, and can achieve a reduction in the size of the crystal resonator. Further, as described with reference to FIG. 1, even in the structure of the crystal resonator described with reference to FIG.
Since nickel has a sealing film 59 is, good crystal oscillator of heat resistance can be obtained.

FIG. 3 does not correspond to the embodiment of the present invention ,
It is sectional drawing which shows the crystal resonator applied to the flat type | mold container, making a crystal resonator compatible with SMD. A quartz piece 63 is supported and fixed by a bonding material 65 on a support member 61 made of ceramic having a concave portion. Thereafter, a lid 69 made of ceramics is disposed on the support member 61, and a sealing film 71 is formed by a vacuum deposition method using a vacuum device.
9 is sealed.

The material of the sealing film 71 of the quartz oscillator of the flat container shown in FIG. 3 is SiO ₂ or Al ₂ O _3.
Use a membrane. The reason for using an insulating film such as SiO ₂ as a sealing film 71, because that does not generate an electrical short circuit due to a solder between the plurality of lead-out electrodes 67 formed on the support member 61.

[0031] corresponding to the SMD, the crystal resonator flat container shown in FIG. 3, although conventionally had been using a low melting glass for bonding of the support member 61 and the lid 69, the present invention
If applied , sealing is performed at a low temperature in a vacuum, so that gas generation from the sealing film 71, the support member 61, and the like is small, and the characteristics of the crystal unit do not deteriorate. Therefore, sealing can be performed at a high yield. Further, as described with reference to FIGS. 1 and 2, also in the structure of the crystal unit described with reference to FIG. 3, since a material having a high melting point is used as the sealing film 71,
A crystal unit having good heat resistance can be obtained.

FIG. 4 shows one embodiment of a method for sealing a quartz oscillator according to the present invention.
Is a sectional view showing an example, which is an example of forming the sealing film 83 by vacuum deposition. For the support member that supports the crystal blank ,
Cover the crystal blank so that part of the outer periphery of the support member is exposed.
The quartz oscillator 81 press-fitted and fixed to the vacuum
The crystal vibrator 81 is fixed to the rotating jig 79 in 3 so as to be rotatable by the motor 87. Evaporation source 7 of vacuum device 73
5 is provided with an evaporating material 89 such as nickel . Evaporation source 75
Is set to a state in which the evaporation material 89 can be heated and melted by resistance heating, electron beam or the like. Thereafter, the inside of the vacuum device 73 is evacuated from the exhaust port 77 using a vacuum pump, and the degree of vacuum is reduced to 1
And 0- ⁵ Toor. At this time, press-fit the support member and lid
The inside of the crystal oscillator 81 is also evacuated through the gap between the parts.
It is. Thereafter, when the evaporation source 75 is heated and the evaporation material 89 is melted, the evaporation material 89 is melted and becomes evaporation particles 85 and scatters in the direction of the vibrator 81. When the vibrator 81 is rotated by the rotating jig 79, the evaporated particles 85
, A sealing film 83 is formed on the outer periphery of the support member and the lid, and the sealing member 83 can seal the support member and the lid.

[0033] In this case, the container of the crystal oscillator 81 becomes high vacuum, since the heat applied to the crystal oscillator 81 is also of the low temperature 200 ° C. approximately, gas generation is small in the container of the crystal oscillator 81, it clean High-vacuum sealing of the crystal unit becomes possible.

[0034] In the above embodiment was formed a sealing film 83 <br/> by a vacuum deposition method using a vacuum deposition apparatus as a vacuum device 73, in addition to vacuum deposition apparatus as a vacuum apparatus, a sputtering apparatus, an ion plating device, or plasma <br/> Ma chemical vapor deposition using (plasma CVD) apparatus, its
Sputtering is a method of forming a vacuum film corresponding to each vacuum device.
Ring method, ion plating method, or plasma
A similar sealing film can be formed by the CVD method .

[0035]

As is apparent from the above description, the use of the quartz resonator and the method of sealing the quartz resonator according to the present invention makes it possible to seal the support member and the lid only at the outer peripheral portion thereof at a low temperature. Can be. In addition, the size of the crystal unit can be made smaller than before. Since a material having a higher melting point is used as the sealing film, a crystal oscillator having good heat resistance can be obtained.
The sealing between the support member and the lid is performed by forming a vacuum coating in a vacuum device.
It is possible to vacuum sealing by law.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structure of an embodiment of a quartz oscillator according to the present invention.

FIG. 2 is a cross-sectional view showing the structure of another embodiment of the crystal resonator according to the present invention.

FIG. 3 is a cross-sectional view illustrating a structure of a crystal unit to which the present invention is applied .

FIG. 4 is a cross-sectional view showing one embodiment of a method for sealing a crystal unit according to the present invention.

FIG. 5 is a cross-sectional view showing a conventional crystal unit.

6 is a sectional view showing an example of a conventional crystal oscillator.

7 is a sectional view showing another example of a conventional crystal oscillator.

[Explanation of symbols]

 41, 53 Support member 43, 57 Lid 45, 55 Quartz piece 47 Bonding material 49, 59,83 Sealing film51 Protective film  73 vacuum equipment75 evaporation source 79 Rotating jig 81 crystal oscillator 89 Evaporation material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-20909 (JP, A) JP-A-3-1605 (JP, A) JP-A-2-228111 (JP, A) JP-A-63-1988 262911 (JP, A) JP-A-61-113292 (JP, A) JP-A-60-400,000 (JP, A) JP-A-51-71084 (JP, A) Japanese Utility Model Laid-Open No. 64-51320 (JP, U) Japanese Utility Model Application Sho 62-19815 (JP, U) Japanese Patent Publication No. 60-16128 (JP, B2) Japanese Patent Publication No. 59-6482 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) H03H 9/00-9/215 H03H 9/54-9/60 H03H 3/00-3/04

Claims (7)

(57) [Claims] 1. A support member for supporting a crystal blank, and fixed to the support member such that a part of the outer periphery of the support member is exposed.
A cover for covering the quartz piece by exposure, and an exposed portion on an outer periphery of the support member.
And a sealing film made of nickel provided on an outer peripheral portion of the lid . 2. The crystal resonator according to claim 1, wherein
A dense layer made of chromium is formed under the sealing film made of nickel.
A crystal unit characterized by forming an adhesion improving film . 3. The crystal resonator according to claim 1, wherein
Silicon oxide or aluminum oxide is formed on the sealing film.
A crystal unit characterized by forming a protective film made of a crystal. The 4. crystal element to a support member for supporting, the support
Lid for covering the crystal blank so that a part of the outer periphery of the member is exposed
Was placed a crystal vibrator pressed into the vacuum apparatus, then the vacuum apparatus is evacuated to a predetermined degree of vacuum, then the
Of the support member by a vacuum film forming method in accordance with the vacuum device
A sealing method for a quartz oscillator , wherein a sealing film is formed on an outer peripheral portion and an outer peripheral portion of the lid . 5. The method according to claim 5, wherein the sealing film is formed of nickel.
The method for sealing a quartz oscillator according to claim 4, wherein: 6. The vacuum device is a vacuum deposition device, a sputtering device, a plasma CVD device, or an ion plating device, and the vacuum film forming method is a vacuum coating method.
Vapor deposition, sputtering, plasma CVD, or
Claims, characterized in that is an ion plating method
Item 6. The method for sealing a quartz oscillator according to item 4 or 5 . 7.The method according to any one of claims 4 to 6,
In the method of sealing a crystal resonator, In the vacuum device, the quartz oscillator is rotated by a rotating jig.
While rotating Forming the sealing film.
How to seal a crystal unit.