JP2013110492A - Package for electronic device, electronic device, electronic apparatus, and manufacturing method of electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package for an electronic device which reliably prevents a sealing member from being scattered by gas discharged from a sealing hole by using a simple method without using a cover plate causing the productivity deterioration.SOLUTION: A package for an electronic device has a container 2 having a void space therein and a sealing hole allowing the void space to communicate with the exterior; and a sealing member 38 which solidifies after melting thereby sealing the sealing hole. A first metal film 45 is formed over entire peripheries of a surface of an outer peripheral edge of the sealing hole and an inner wall. Further, a second metal film 45 is formed on at least a part of the surface 37a' of the outer peripheral edge of the sealing hole. The melting point of the second metal film is lower than the melting point of the first metal film.

Description

  The present invention relates to improvements in a package for an electronic device in which a piezoelectric vibration element and other electronic components are housed in a container, an electronic device, an electronic apparatus, and an electronic device manufacturing method.

In recent years, in small information devices such as HDDs (hard disk drives), mobile computers, and IC cards, and mobile communication devices such as mobile phones, car phones, and paging systems, the size and thickness of devices have been dramatically reduced. The piezoelectric devices used for them are also required to be small and thin. In addition, there is a need for a surface-mount type piezoelectric device that can be surface-mounted on a circuit board of the apparatus.
In the manufacturing process of an electronic device having a structure in which a piezoelectric vibration element is hermetically sealed in a container like a piezoelectric vibrator, after the piezoelectric vibration element is accommodated in a container having a sealing hole, the container is The gas inside the container is discharged from the sealing hole by being placed in a vacuum chamber and heated while being vacuumed, and the sealing hole is sealed using a sealing member when the discharge is completed.
In the sealing step, the container is set so that the sealing hole faces upward in the vacuum chamber, and a spherical metal sealing member is placed so as to close the sealing hole, and then the laser beam is applied to the sealing member. The sealing hole is sealed by irradiation and melting (Patent Document 1).
With the miniaturization of electronic devices, the sealing member is also miniaturized. For example, metal balls having a diameter of about 0.3 mm are used. Such a small, lightweight metal sphere is easily pushed out of the container by the gas discharged from the inside of the container through the sealing hole when vacuumed, and the sealing process cannot be carried out when scattered. This is a cause of reducing the productivity of the piezoelectric device.
In order to prevent the sealing member from being scattered by evacuation, the evacuation speed is reduced, but not only the cost for remodeling the vacuum chamber is increased, but the productivity is lowered. This is a cause of deterioration of the properties of the finished product due to a decrease in the degree of vacuum in the electronic device and variations.

On the other hand, Patent Document 2 discloses a method for manufacturing a small piezoelectric device capable of hermetically sealing a piezoelectric vibration element in a container. In this manufacturing method, a spherical sealing member is disposed in a sealing hole of a container disposed in a vacuum chamber, and then the inside of the container is decompressed by depressurizing the inside of the vacuum chamber, and the inner periphery of the sealing hole and the sealing are sealed. The gas inside the container is discharged to the outside through a gap with the member. At this time, the cover plate is arranged so that the gap between the outer bottom surface of the container in which the sealing hole is formed and the cover plate is smaller than the diameter of the sealing member. When a spherical sealing member tries to jump out of the sealing hole due to the pressure of the gas discharged from the internal space, the sealing member is received by the cover plate.
However, when the container is downsized to a few mm square, a spherical sealing member for sealing the sealing hole formed in the container has a diameter of 1 mm or less, for example, and a plurality of spherical sealing members are set on the tray. It is extremely difficult to maintain a proper gap between all the containers and the cover. In addition, there is a problem that productivity decreases as the work for preparing and setting and removing the cover plate increases.

JP 2003-158439 A JP 2011-129735 A

  The present invention has been made in view of the above, and it is ensured that the sealing member is scattered by the gas discharged from the sealing hole by a simple method without using a cover plate that causes a decrease in productivity. An object of the present invention is to provide an electronic device package, an electronic device, and a method for manufacturing the electronic device that can be prevented.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A package for an electronic device according to the present invention has a void inside, communicates the void with the outside, and further seals by melting and solidifying the sealing member. A package for an electronic device having a container having a hole, wherein a first metal film is formed on a peripheral surface outside the sealing hole, and the outside of the sealing hole A second metal film is formed on at least a part of the peripheral surface of the first metal film, and the melting point of the second metal film is lower than the melting point of the first metal film.

  According to this application example, before the decompression step and the main sealing step, a cover plate that causes a decrease in productivity is used to perform a melting step for temporarily fixing the sealing member to the sealing hole. In addition, it is possible to reliably prevent the sealing member from being scattered by the gas discharged from the sealing hole by a simple method. As a method of temporarily fixing the sealing member, the second metal film is formed around the sealing hole and the second metal film is melted, so that productivity can be improved.

  Application Example 2 The electronic device package according to the present invention is characterized in that, in Application Example 1, the second metal film is formed on the first metal film.

  The second metal film may be formed on the first metal film. Since the sealing member can be temporarily fixed by melting the second metal film, scattering of the sealing member can be prevented and the decompression process can be made efficient.

  Application Example 3 In the electronic device package according to the application example 1, in the application example 1, the second metal film is formed on a peripheral surface outside the sealing hole where the first metal film is not present. It is characterized by.

  The second metal film may be formed in a portion where the first metal film does not exist. Since the sealing member can be temporarily fixed by melting the second metal film, scattering of the sealing member can be prevented and the decompression process can be made efficient.

  Application Example 4 In the electronic device package according to the application example 1 to 3, in the application examples 1 to 3, gold is used as the first metal film, and a gold-tin alloy is used as the second metal film. Features.

  A gold-tin alloy has a low melting point and is suitable as a metal material for temporary fixing.

  Application Example 5 An electronic device according to the present invention is the electronic device package according to any one of Application Examples 1 to 4, the sealing member, and an electronic component disposed in a space of the container. And.

  According to this application example, since the productivity of the electronic device package is increased, the productivity of the electronic device can be increased and the cost can be reduced.

  Application Example 6 The electronic device package according to the present invention is characterized in that, in Application Example 5, a gold-germanium alloy is used as the sealing member.

  According to this application example, since a gold-germanium alloy having a high melting point is used, it does not easily melt when heat is applied in the process of mounting the piezoelectric device after sealing. Is effectively prevented from leaking due to partial melting of the sealing member. Moreover, since the sealing member does not contain lead, environmental pollution caused by lead can be avoided.

  Application Example 7 An electronic apparatus according to the present invention includes the electronic device described in Application Example 6.

  Application Example 8 An electronic device manufacturing method according to the present invention includes a container having a void inside and a sealing hole that communicates the void with the outside, and solidifying after melting. A sealing member that seals the stop hole; and an electronic component that is housed in the container having the sealing hole sealed by the sealing member, and the outer peripheral surface of the sealing hole A first metal film is formed on the upper and inner walls over the entire circumference, and a second metal film is formed on at least a part of the outer peripheral surface of the sealing hole. The melting point of the metal film is a method for manufacturing an electronic device having a melting point lower than that of the first metal film, the step of accommodating the electronic component in the void of the container, and the sealing hole facing upward A container setting step for setting the container on the sealing member, and sealing for disposing the sealing member on the sealing hole. A material disposing step, a first melting step for melting the second metal film, a decompression step for decompressing the void of the container after the first melting step, and a first melting step for melting the sealing member. In the first melting step, in the state in which communication between the empty space of the container and the outside of the container is ensured, the second metal film forms the inside of the sealing hole or the sealing. The sealing member is fixed to a peripheral edge portion of the stop hole.

  According to this application example, before the decompression step and the main sealing step, a cover plate that causes a decrease in productivity is used to perform a melting step for temporarily fixing the sealing member to the sealing hole. In addition, it is possible to reliably prevent the sealing member from being scattered by the gas discharged from the sealing hole by a simple method. As a method of temporarily fixing the sealing member, the second metal film is formed around the sealing hole and the second metal film is melted, so that productivity can be improved.

1 is a schematic plan view of an electronic device using a piezoelectric device package according to an embodiment of the present invention. FIG. 2 is a schematic sectional view taken along line XX in FIG. 1. It is a bottom view of FIG. (A) (b) And (c) is a longitudinal cross-sectional view which shows the procedure which mounts a piezoelectric vibration element in a container main body, the bottom view which shows a sealing hole periphery, and explanatory drawing which shows the procedure which joins a cover body. . It is a flowchart explaining the manufacturing method of the electronic device which concerns on this invention. (A) And (b) is a figure explaining the sealing method using a laser beam, and the principal part enlarged view. (A) And (b) is explanatory drawing which shows the state which irradiates a laser beam toward a 2nd metal film in a 1st fusion | melting process, and sectional drawing which shows the sealing member temporarily fixed. It is the figure which showed an example of the temperature profile in a pressure reduction process. It is sectional drawing explaining the 2nd melting process which fuses a sealing member. (A) And (b) is explanatory drawing which shows the structure of the 2nd metal film in other embodiment of this invention, and a longitudinal cross-sectional view. (A) is a schematic plan view which shows the structure of different embodiment of the piezoelectric device of this invention, (b) is a XX sectional schematic drawing of (a). 1 is a diagram illustrating a schematic configuration of a digital mobile phone device as an example of an electronic apparatus using a piezoelectric device according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
1 to 3 show one embodiment of an electronic device using the electronic device package of the present invention, FIG. 1 is a schematic plan view thereof, and FIG. 2 is a schematic sectional view taken along line XX of FIG. FIG. 3 is a bottom view of FIG. 4 (a), 4 (b) and 4 (c) are longitudinal sectional views showing a procedure for mounting the piezoelectric vibration element in the container body, a bottom view showing the periphery of the sealing hole, and a procedure for joining the lid. It is explanatory drawing.

In these drawings, a piezoelectric vibrator is illustrated as the piezoelectric device 1, and the piezoelectric device 1 has a configuration in which a piezoelectric vibration element (electronic component) 30 is hermetically sealed in a container 2.
The container 2 includes a container main body 3 and a lid body 20 that is assembled to hermetically seal the piezoelectric vibration element 30 mounted on the container main body 3.
The container body 3 is formed of a substrate such as an aluminum oxide sintered body obtained by laminating and sintering ceramic green sheets. Each of the plurality of substrates is formed with a predetermined hole on the inner side thereof so that a predetermined inner space S is formed on the inner side when stacked. That is, as shown in FIG. 2, the container body 3 of the present embodiment includes, for example, a flat plate-like first laminated substrate 11, an annular second laminated substrate 12 overlaid thereon, and an overlaid thereon. And an annular third laminated substrate 13.
In the vicinity of the left end portion in the internal space S of the container main body 3, the second laminated substrate 12 that is exposed to the internal space S and forms the bottom portion is provided with electrode portions 15 and 15 plated with Au and Ni. Is provided. The electrode portions 15 and 15 are connected to the outside to supply a driving voltage. Conductive adhesives 16, 16 are applied on the electrode parts 15, 15, and a base 31 of the piezoelectric vibration element 30 is placed on the conductive adhesives 16, 16, so that the conductive adhesives 16, 16 are placed. Is cured.

An extraction electrode (not shown) for transmitting a driving voltage is formed on a portion of the base 31 of the piezoelectric vibration element 30 that is in contact with the conductive adhesives 16 and 16, whereby the piezoelectric vibration element 30 is driven. The electrode is electrically connected to the electrode parts 15 and 15 on the container body 3 side via the conductive adhesives 16 and 16.
The piezoelectric substrate constituting the piezoelectric vibration element 30 is made of, for example, quartz, and a piezoelectric material such as lithium tantalate or lithium niobate can be used in addition to the quartz. In the case of this embodiment, the piezoelectric vibration element 30 includes a base 31 fixed to the container body 3 side, and a pair of vibrating arms 34 and 35 extending from the base 31 in a bifurcated manner toward the right side of the drawing. A so-called tuning fork type piezoelectric vibration element is used which has a tuning fork shape as a whole.
The open upper surface of the container body 3 is sealed by joining a metal lid 20 via a brazing material 33 such as low melting point glass.

In addition, by substantially forming first and second through holes 37a and 37b in the two laminated substrates 11 and 12 constituting the bottom plate of the container body 3 in the vicinity of the center of the bottom surface of the container body 3, respectively. A sealing hole 37 as a through hole is provided. Out of the two through holes constituting the sealing hole 37, the outer second through hole 37b is concentrically provided with a larger inner diameter with respect to the first through hole 37a opened inside the container body. It is configured. As a result, the sealing hole 37 is an opening having a stepped portion 40. Preferably, the stepped portion of the second through-hole 37b and the inner peripheral surface of the through-hole 37a are sealed with a sealing member 38 to be described later. A metal ball (for example, a gold germanium alloy (Au / Ge)) is covered with a metal having good wettability, for example, gold plating, by being formed on a predetermined underlayer.
Specifically, as shown in FIG. 4B, a first metal film 45 as a gold plating film is circumferentially provided on the outer peripheral surface 37a ′ of the first through hole 37a and the inner wall 37a ″. Films are formed continuously (over the entire circumference). Further, a second metal film 47 is formed on at least a part of the outer peripheral surface 37a ′. The second metal film 47 is made of a material having a melting point lower than that of the first metal film 45. For example, a gold-tin alloy (Au—Sn alloy) is used as the second metal film. The melting point of gold is 1064 ° C., and the melting point of the gold-tin alloy is 356 ° C.
After the piezoelectric vibration element 30 is fixed in the container body 3, a sealing member (metal sealing member) 38 is melt-filled in the sealing hole 37, thereby sealing the inside of the container body 3 in an airtight state. .

In this example, a gold germanium alloy (Au / Ge) is used as the sealing member 38 filled in the sealing hole 37, as will be described in detail in a sealing process described later. Note that any other metal material can be used as the sealing member.
The container 2 and the sealing member 38 that seals the sealing hole 37 constitute a package P of the electronic device.
Further, in this embodiment, the second laminated substrate 12 constituting the container body 3 is formed with a recess 42 corresponding to the thickness of the laminated substrate 12 by forming a hole near the right end of the drawing. . The recess 42 is located below the piezoelectric vibration element 30. Thus, in the present embodiment, when an external impact is applied to the container body 3, even when the free end of the piezoelectric vibration element 30 is displaced in the direction of arrow D and shakes, the container body 3 contacts the inner bottom surface. To prevent it.
The piezoelectric device 1 according to the present embodiment is configured as described above, and the sealing hole 37 provided in the container body 3 is sealed with a sealing member 38 made of a gold germanium alloy (Au / Ge). For this reason, when heat is applied in the process of mounting the piezoelectric device 1 after sealing, the gold germanium alloy has a high melting point and does not melt easily. Leakage due to partial melting is effectively prevented. In addition, since the sealing member 38 does not contain lead, environmental pollution caused by lead can be avoided.

Next, the package P of the electronic device of the present invention has the following characteristic configuration.
That is, the package P of the electronic device seals the sealing hole by solidifying the container 2 having the void S inside and the sealing hole 37 that communicates the void with the outside. A first metal film 45 is continuously formed over the entire circumference on the outer peripheral surface 37a ′ of the first through hole 37a and on the inner wall 37a ″. The second metal film 47 is formed on at least a part of the outer peripheral surface of the sealing hole, and the melting point of the second metal film 47 is lower than the melting point of the first metal film 46. Yes.
In addition, the second metal film 47 may be laminated on the first metal film 45, or directly formed on the outer peripheral surface 37a ′ (underlying metal layer) where the first metal film 45 does not exist. May be.
As shown in FIG. 4B, the first metal film 45 (45a) is continuously formed on the inner peripheral surface of the first through hole 37a over the entire circumference, and the first through hole is formed. The first metal film 45 (45b) continues in the circumferential direction also on the outer peripheral surface 37a ′ of the first through hole located between the inner wall of the hole 37a and the inner wall of the second through hole 37b ( The film is formed over the entire circumference.

Further, a second metal film 47 is laminated and formed on at least a part of the first metal film 45 (45b) on the outer peripheral surface 37a ′. The second metal film 47 may be formed in a continuous annular shape on the outer peripheral surface 37a ′, or may be formed so as to be within a range of 180 degrees as shown. The radial position and the shape of the second metal film 47 are between the inner wall of the second through hole 37b and the outer peripheral edge of the sealing member 38 seated on the periphery of the first through hole 37a. The region is set so that at least a part of the second metal film 47 can be irradiated with laser light from above.
Note that the second metal film 47 may be formed in an annular shape so as to surround the entire circumference of the upper opening of the first through hole 37a. In this case, by limiting the portion irradiated with the laser light to a part of the second metal film, only a part of the second metal film 47 is melted and only a part of the sealing member is the first. It is possible to fix to the periphery of the through hole.

As will be described later, the second metal film 47 is melted and solidified by laser light before the main sealing step, so that the sealing member 38 and the peripheral edge of the first through hole 37a are partially fixed. In order to temporarily fix the sealing member, the second metal film 47 is provided.
In the illustrated embodiment, the first through hole 37a having a small diameter and the second through hole 37b having a large diameter are provided as the sealing holes 37 in the axial direction. The present invention is not limited to the configuration and can be applied to a sealing hole having the same inner diameter over the entire axial length.

Next, the manufacturing method of the electronic device of this invention is demonstrated.
That is, the present invention includes a container 2 having a void S inside and a sealing hole 37 that communicates the void with the outside, and a seal that seals the sealing hole by solidifying after melting. A member 38 and an electronic component 30 housed in a container whose sealing hole is sealed by a sealing member. The outer peripheral surface 37a 'of the sealing hole and the inner wall 37a'' The first metal film 45 is continuously formed over the circumference, and the second metal film 47 is formed on at least a part of the outer peripheral surface 37a ′ of the front sealing hole. The present invention relates to a method for manufacturing an electronic device having a melting point lower than that of a first metal film.
The characteristic configuration of the manufacturing method according to the present invention includes a step of accommodating the electronic component 30 in the space S of the container 2, a container setting step of setting the container 2 so that the sealing hole 37 faces upward, A sealing member placement step for placing the sealing member 38 on the sealing hole 37, a first melting step for melting the second metal film 47, and the container 2 that has undergone the first melting step in the chamber 51a. And a decompression step for decompressing the space S of the container by decompressing the inside of the chamber, and a second melting step for melting the sealing member 38 in a state where the space is decompressed, In the first melting step, in a state in which communication between the void of the container and the outside of the container is ensured, a sealing member is formed in the sealing hole by the second metal film 47 and / or in the peripheral portion of the sealing hole. It is in the point of fixing.

Next, FIG. 5 is a flowchart illustrating a method for manufacturing an electronic device according to the present invention.
In FIG. 5, the manufacturing process of the container and the piezoelectric vibration element is not shown, and is simplified and shown as a container body preparation process (step S1) and a piezoelectric vibration element preparation process (step S2).
In the container body 3 preparation step shown in step S1, the container body 3 is manufactured and prepared. The container body 3 can be formed by using an insulating material such as ceramic or glass, and more specifically, an aluminum oxide ceramic green sheet can be formed and used. A material such as a ceramic green sheet is formed, two laminated substrates 11 and 12 having concentric through holes 37a and 37b having different diameters are laminated, and a rectangular annular shape is formed on the second laminated substrate 12. The third laminated substrate 13 is laminated and then fired to obtain the outer shape of the container body 3 in which the concave portions having steps are formed.
Each through-hole 37a, 37b may be a circular hole or a non-circular hole.

The outer bottom surface of the first multilayer substrate 11 is formed at a suitable position on the outer surface of the container body 3 made of an insulating material, for example, by performing tungsten metallization, nickel plating and gold plating, and using photolithography together. External mounting terminals (not shown) provided on the electrode layer 15, electrode portions 15 provided on the upper surface of the second laminated substrate 12, and the like are formed. At the same time, a metal film that is compatible with the sealing member is formed on the inner peripheral surface and the outer peripheral edge of the sealing hole 37. In addition, said various terminals provided in the container main body 3 connect corresponding terminals to each other by routing wiring or in-layer wiring such as a through hole formed in advance on each laminated substrate.
For example, gold is used as the metal film that is compatible with the sealing member formed on the inner peripheral surface of the sealing hole 37 and the outer peripheral edge, that is, the first metal film 45.
The first metal film 45 is circumferentially formed on the first metal film 45a continuously formed over the entire inner peripheral surface of the first through hole 37a and the outer peripheral surface 37a ′ of the first through hole. The first metal film 45b is continuously formed over the entire length, and both the first metal films 45a and 45b are electrically connected.
Furthermore, a second metal film 47 made of a material having a melting point lower than that of the first metal film 45 is formed on at least a part of the first metal film 45b on the outer peripheral surface 37a ′. .
Note that a region where the first metal film 45b does not exist may be formed in a part of the first metal film 45b, and the second metal film 47 may be disposed in this region. When forming the first metal film 45b, a region where the first metal film 45b does not exist is formed by using a photolithography technique, and then a second metal film 47 is formed in this region using a mask. It is easy.

In the step of preparing the piezoelectric vibration element shown in step S2, the piezoelectric vibration element 30 is manufactured and prepared. In manufacturing the piezoelectric vibration element 30, first, a large-sized piezoelectric substrate cut out at a predetermined cut angle with respect to the crystal axis, for example, a quartz substrate (quartz wafer) is prepared, and wet etching using photolithography or dry etching is performed. The external shape of the quartz substrate is formed by etching.
Next, electrodes such as excitation electrodes and external connection terminals are formed by sputtering or vapor deposition. The electrode can be formed by forming a chromium layer as a base on the surface of a quartz substrate on which the outer shape of the piezoelectric vibration element is formed, by sputtering or vapor deposition, and laminating a gold layer thereon.
Then, by dicing the wafer on which the plurality of piezoelectric vibration elements 30 are formed, a plurality of pieces of piezoelectric vibration elements are obtained.

Next, the piezoelectric vibration element joining step will be described.
In the piezoelectric vibration element joining step shown in step S3, the piezoelectric vibration element 30 is disposed on the electrode portion 15 provided in the concave portion of the container body 3 by using the conductive adhesive 16 to make electrical and mechanical connection. Join with it.
Specifically, in FIG. 4A, a brazing material 33 such as sealing glass is applied in advance to the upper surface of the outer peripheral wall of the container body 3, and a conductive adhesive 16 is applied on the electrode portion 15 in the recess. The piezoelectric vibration element 30 is placed in a container by placing a portion of an extraction electrode (not shown) provided on the base 31 of the piezoelectric vibration element 30, positioning it with a light load, and curing the conductive adhesive 16. Mount in the body 3.

Next, the frequency adjustment process of the piezoelectric vibration element 30 in step S4 is performed.
In the frequency adjustment step, first, the initial frequency of the piezoelectric vibration element 30 is measured, and the difference between the initial frequency and the target frequency is adjusted to a small allowable range. The frequency adjustment of the piezoelectric vibration element 30 is performed, for example, by irradiating the piezoelectric vibration element 30 with a laser or an ion beam and etching a part thereof by a predetermined amount. The piezoelectric vibration element 30 is known to increase the vibration frequency by reducing the mass of the vibration part. For example, a part of the electrode pattern other than the excitation electrode formed on the piezoelectric vibration element 30 is etched. Thus, the frequency of the piezoelectric vibration element 30 can be adjusted to be high without changing the shape of the excitation electrode. In the case of using the frequency adjusting method based on the mass reduction method, the initial frequency of the piezoelectric vibration element 30 is made to be a lower frequency than the target frequency. Contrary to the mass reduction method described above, frequency adjustment can also be performed by adding mass to the vibrating portion of the piezoelectric vibration element 30 to reduce the frequency (mass addition method). As a method for adding mass, a method of depositing a metal film on the vibration part of the piezoelectric vibration element 30 by sputtering or vapor deposition can be used. When the frequency adjustment is performed by this mass addition method, the initial frequency of the piezoelectric vibration element 30 is made to be higher than the target frequency.

Next, as shown in step S <b> 5, the lid 20 is joined to the open upper end of the outer peripheral wall of the container body 3. The container body 3 and the lid 20 are joined to each other by providing a seal ring as a brazing material made of, for example, a Kovar (Fe—Ni—Co) alloy on the upper end surface of the container body 3. It can be performed by seam welding the lid 20.
Specifically, as shown in FIG. 4C, for example, in the chamber 51 for forming a nitrogen atmosphere, the lid body 20 is placed on the tray 54 on the support base 53, and the above-described lid body 20 is placed thereon. The container body 3 is placed upside down so that the brazing material 33 comes into contact with the lid body 20, and the inside of the chamber 51 is heated while applying a load by the weight 52 from above. Thereby, the lid 20 is joined by melting and hardening the brazing material 33. Note that this step may be performed through the piezoelectric device 1 in a belt furnace in which a nitrogen atmosphere is controlled instead of the chamber 51.
The process of housing the piezoelectric vibration element 30 (electronic component) in the container is completed by steps S3 to S5.

The piezoelectric vibration element 30 joined in the internal space S formed by joining the lid 20 on the container body 3 is moved to the sealing step (S6 to S11) and sealed.
The sealing step is performed, for example, by accommodating the container 2 (container main body 3, lid body 20) containing a piezoelectric vibration element inside a vacuum chamber 51a or the like as shown in FIG. At this time, the container 2 is set upside down so that the sealing hole 37 faces upward.
First, as shown in step S6, a spherical sealing member 38 made of an alloy of gold and germanium, an alloy of gold and tin, or the like is disposed in a sealing hole 37 provided on the bottom surface of the container body 3. To do. The spherical sealing member 38 can be arranged by utilizing the inner peripheral shape of the sealing hole 37. That is, by using the step shape of the sealing hole 37 in which the through hole 37a on the inner space S side and the concentric (outer side) through hole 37b larger than the through hole 37a communicate with each other, the container 2 Is placed so that the inner space S side is on the lower side, so that the spherical sealing member 38 inserted from the outer side of the sealing hole 37 is held by the step portion 40 in the sealing hole 37. Is done.

The process of FIG. 6A will be described in more detail. As shown in FIG. 6B, which is an enlarged view of a part of FIG. 6A, a sealing hole 37 in which a sealing member 38 of a spherical gold germanium alloy (Au / Ge) alloy is disposed. Is provided with an inner first through-hole 37a having a predetermined inner diameter n1 and an inner diameter n2 larger than the first through-hole 37a, and is open to the outside. Second through hole 37b. The diameter n3 of the spherical gold germanium alloy (Au / Ge) alloy sealing member 38 is larger than the inner diameter n1 of the first through hole 37a and slightly smaller than the inner diameter n2 of the second through hole 37b. ing.
Therefore, the spherical gold germanium alloy sealing member (Au / Ge) 38 is in contact with the ridgeline of the edge e (step 40) of the inner peripheral edge of the first through hole 37a as shown in the drawing. Is held. At this time, the second metal film 47 is exposed between the inner wall of the second through hole 37 b and the outer peripheral contour of the sealing member 38. That is, when the sealing hole 37 is viewed from above, the presence of the second metal film 47 can be confirmed on the outer peripheral surface 37a ′ located between the sealing member and the inner wall of the second through hole 37b. . Therefore, in the first melting step to be described later, the second metal film 47 can be melted by irradiating the second metal film 47 with laser light from the laser irradiation means 55 as shown in FIG.

Next, in step S7, a first melting step (temporary fixing step of the sealing member) that characterizes the present invention is performed.
In the first melting step, as shown in FIG. 7A, a second exposed and disposed on the outer peripheral surface 37a ′ located between the sealing member 38 and the inner wall of the second through hole 37b. The metal film 47 is melted by being irradiated with laser light from the laser irradiation means 55. The second metal film 47 is melted and then cured, so that the second metal film 47 and a part of the sealing member 38 are fixed, while the sealing member 38 except for the fixed part is fixed. A ventilation gap G is formed between the outer surface and the inner peripheral edge of the first through hole 37a. In this temporarily fixed state, the sealing member maintains a state where a part thereof is fixed to the sealing hole (first through hole 37a) while keeping the internal space S and the outside of the container in communication.
As a result of the sealing member 38 incompletely closing the first through-hole 37a in the first melting step, the gas in the container is caused to become a gap G between the sealing member and the sealing hole by heating in the subsequent decompression step. While being discharged efficiently, the lightweight sealing member does not detach from the periphery of the sealing hole and scatter due to the gas pressure discharged.
A part of the upper surface of the vacuum chamber 51a is a glass plate, and the laser beam L from the laser irradiation means 55 arranged outside is irradiated to the second metal film 47 through the glass plate.

Next, in the depressurization step of Step S8, the internal space S of the container 2 is depressurized by depressurizing the inside of the vacuum chamber, and heated through the gap G between the inner periphery of the sealing hole 37 and the sealing member 38. The gas inside the container 2 generated by the above is discharged to the outside of the container 2. That is, harmful gas (outgas) generated in the curing process of the conductive adhesive 16 such as silver paste used for bonding the piezoelectric vibration element 30 and the electrode unit 15 described in step S3, or the inside of the container 2 (inside The gas in which the water in the space S) is evaporated is discharged to the outside in this decompression step.
That is, in the decompression process of step S8, as shown in FIG. 7, the sealing member 38 is temporarily fixed to the sealing hole 37 by melting and solidifying the second metal film 47 in the first melting process. The container 2 is disposed in the vacuum chamber 51a, and the inside of the vacuum chamber 51a is evacuated by a vacuum exhaust means (not shown), preferably in a high vacuum state.
At this time, the sealing member 38 that has passed through the first melting step is securely fixed around the sealing hole while maintaining a gap for ventilation, so that the sealing member pops out when evacuating. There is no fear of dropping out. For this reason, the speed and strength of evacuation can be increased, and productivity can be increased. At the same time, the degree of vacuum in the container can be increased to eliminate variations in the degree of vacuum, so that device characteristics can be improved and characteristic variations can be reduced.

FIG. 8 shows an example of a temperature profile in the decompression step. That is, the inside of the vacuum chamber 51a is set to a high vacuum of about 10 ⁻³ Pa (pascal), for example. Then, during T1 time (for example, 20 minutes), heating is performed to 250 to 300 degrees, preferably 260 degrees or more. This temperature is maintained for T2 hours (for example, 30 minutes), and a gas component generated from, for example, the conductive adhesive 16 in the container 2 is discharged out of the container 2.
Subsequently, the vacuum hole sealing step (second melting step) is performed for T3 time (for example, 20 minutes) while maintaining the temperature and pressure in the vacuum chamber 51a. At this time, the melting temperature of the gold germanium alloy (Au / Ge) sealing member 38 is high even if the ambient temperature is high. And the gas component can be effectively driven out. Then, the laser beam L is irradiated from the laser irradiation means 55 toward the sealing member 38 to melt and solidify the temporarily fixed sealing member 38, thereby completely closing the through hole 37 (S9, S10). )).

In the second melting step of step S9, the laser beam L is applied to the sealing member 38 of a gold germanium alloy (Au / Ge) alloy temporarily fixed in the sealing hole (FIG. 9). Although the melting point of the sealing member 38 of the gold germanium alloy (Au / Ge) alloy is about 360 degrees, the laser beam L has a property that the sealing member 38 of the present embodiment easily absorbs light. Therefore, the spherical gold germanium alloy (Au / Ge) alloy 38 can be appropriately melted by irradiating under substantially the same conditions as in the case of gold tin.
When the sealing member 38 is melted to seal the sealing hole 37, the molten sealing member is integrated with the first metal film 45 and the second metal film 47 and fixed to the sealing hole. .
Then, the atmosphere is released and the process ends (step S11).
As described above, in the method for manufacturing a piezoelectric device (electronic device) according to the present embodiment, a spherically formed gold germanium alloy (Au / Ge) is sealed with respect to the through hole 37 formed in the bottom of the container body 3. The stop member 38 is arranged, and the sealing member is temporarily fixed (unsealed) to the periphery of the first through-hole 37a by melting the second metal film 45 in the first melting step, and then the second metal film 45 is melted. In the melting step, the sealing member is melted (main sealing).
For this reason, it can prevent reliably that a sealing member disperses with the gas discharged | emitted from a sealing hole by a simple method, without using the cover board which causes productivity fall.

In addition, since the sealing member can be securely fixed to the sealing hole by temporarily fixing the sealing member before melting and main sealing, the sealing member may be lifted and detached in the decompression process. This makes it possible to sufficiently depressurize and degas the space in the container. For this reason, the characteristic variation of the completed electronic device can be reduced. In addition, since the time for vacuuming (reducing pressure) can be shortened, productivity can be improved and cost can be reduced.
The sealing member 38 made of a gold germanium alloy (Au / Ge) has a high melting point, but is easily oxidized, and an oxide film is easily formed on the surface. It becomes difficult. However, when a gold germanium alloy (Au / Ge) is formed into a spherical shape and irradiated with laser light, the oxide film easily absorbs light and is easily melted due to the oxide film, and the oxide film faces the outside of the through-hole 37. Extruded. Thereby, the through-hole 37 can be completely closed by appropriately flowing the alloy component of the sealing member 38 into the through-hole 37. For this reason, when heat is applied in the process of mounting the piezoelectric device 1 after sealing, the sealing member 38 of the gold germanium alloy has a high melting point and does not easily melt. Is effectively prevented from leaking due to partial melting of the sealing member. In addition, since the sealing member 38 does not contain lead, environmental pollution caused by lead can be avoided.

Moreover, in the said embodiment, although the structural example which laminated | stacked the 2nd metal film 47 on the upper surface of the 1st metal film 45 was shown, the top view of the sealing hole periphery of Fig.10 (a) and (b), As shown in the longitudinal sectional view, a portion 49 where the first metal film 45 is not formed is provided on the outer peripheral surface 37 a ′, and the second metal film 47 is filled in this portion 49 to form the first laminated substrate 11. The second metal film 47 may be disposed directly on the outer surface or via a base metal layer (not shown). Even in such a configuration, the sealing member is temporarily fixed in the first through hole 37a and / or on the outer peripheral surface by melting the second metal film in the first melting step. be able to.
The second metal film 47 disposed in the portion 49 where the first metal film 45 is not formed need not be in contact with the first metal film, and may be separated from each other.
Also in this embodiment, the first metal film 45 is continuous in the circumferential direction. That is, the portion 49 where the first metal film 45 does not exist is merely formed in an island shape in the outer peripheral surface 37a ′, and the first portion is formed at the peripheral portion of the portion 49 as shown in FIG. The metal film 45 is continuous in the circumferential direction.

Fig.11 (a) is a schematic plan view which shows the structure of different embodiment of the piezoelectric device of this invention. In FIG. 11, the piezoelectric device 60 shows an example in which a piezoelectric oscillator is formed by using the piezoelectric vibration element 30, and the portions denoted by the same reference numerals as those in the first embodiment have a common configuration. A duplicate description will be omitted, and the difference will be mainly described.
FIG. 11B is a schematic cross-sectional view taken along the line XX of FIG. 11A, and the container body 61 has a larger number of ceramic sheets than the container body 3 of the first embodiment during the production. Manufactured using a laminated substrate. Thus, the container body 61 is formed with a recess 62 near the center using the increased number of laminated substrates, and an electrode (not shown) is provided on the inner bottom thereof. An integrated circuit 63 is mounted on this electrode. The integrated circuit 63 constitutes a predetermined frequency dividing circuit and the like, and is electrically connected to the drive electrode of the piezoelectric vibration element 30 so that the drive voltage output from the integrated circuit 63 is applied to the piezoelectric vibration element 30. It has become.
The sealing member 38 filled in the through hole 37 of the container main body 61 is the same as that described in the first embodiment, and is sealed in the same sealing process. Therefore, this embodiment can also exhibit the same operational effects as the first embodiment. As described above, the present invention is not limited to the piezoelectric vibrator, and the piezoelectric vibration element is housed in the container body and sealed by the lid body regardless of the name of the piezoelectric oscillator or the filter as shown in FIG. Applicable to any piezoelectric device of the configuration.

FIG. 12 is a diagram showing a schematic configuration of a digital mobile phone device as an example of an electronic apparatus using the piezoelectric device according to the above-described embodiment of the present invention. In the figure, a microphone 108 for receiving the voice of the sender and a speaker 109 for outputting the received content as a voice output are provided. The controller 101 is provided. The controller 101 controls an information input / output unit 102 including an LCD as an image display unit and an operation key for inputting information, and an information storage unit 103 including a RAM and a ROM in addition to modulation and demodulation of transmission / reception signals. Is supposed to do. Therefore, the piezoelectric device 1 is attached to the controller 101, and the output frequency is used as a clock signal suitable for the control content by a predetermined frequency dividing circuit (not shown) built in the controller 101. Has been. The piezoelectric device 1 attached to the controller 101 may be a piezoelectric device 60 as shown in FIG. 11 which is an oscillator combining the piezoelectric device 1 and a predetermined frequency dividing circuit, etc. Good.
The controller 101 is further connected to a temperature compensated crystal oscillator (TCXO) 105, and the temperature compensated crystal oscillator 105 is connected to a transmitter 107 and a receiver 106. As a result, even if the basic clock from the controller 101 fluctuates when the environmental temperature changes, it is corrected by the temperature compensated crystal oscillator 105 and supplied to the transmission unit 107 and the reception unit 106.
In this way, by using the piezoelectric device according to the above-described embodiment in an electronic apparatus such as the mobile phone device 110 including the control unit, the piezoelectric vibration element correctly positioned in the container body can be obtained in the manufacturing process. By using the piezoelectric device provided, an accurate clock signal can be generated.

The present invention is not limited to the above-described embodiment. Each configuration of each embodiment can be appropriately combined or omitted, and can be combined with other configurations not shown.
In the above embodiment, the sealing hole is formed on the container body side, but the sealing method according to the present invention can also be applied to an electronic device having a sealing hole on the lid side. In short, the present invention can be applied to general electronic devices having a sealing hole in any part of the outer surface of the container.
Moreover, although the container main body 3 which concerns on the said embodiment was used as the insulated substrate which has a recessed part in the upper surface, it mounts an electronic component on the flat insulating substrate which does not have a recessed part, and the space on the insulated substrate containing an electronic component is made. The sealing method of the present invention can also be applied to an electronic device that is sealed with a bathtub-type (reverse saddle-shaped) lid. In this case, the sealing hole may be provided on the insulating substrate side or may be provided on the lid side.

DESCRIPTION OF SYMBOLS 1 ... Piezoelectric device, 2 ... Container, 3 ... Container main body, 11, 12 ... Laminated substrate, 15 ... Electrode part, 16 ... Conductive adhesive, 20 ... Lid body, 30 ... Piezoelectric vibration element (electronic component), 31 ... Base part 33 ... Brazing material 34, 35 ... Vibrating arm 37 ... Sealing hole 37a, 37b ... Through hole 37a '... Outer peripheral edge surface 37a' '... Inner wall 38 ... Sealing member 40 ... Step part , 42 ... concave portion 45 (45a, 45b) ... first metal film, 47 ... second metal film, 51 ... chamber, 51a ... vacuum chamber, 52 ... weight, 53 ... support base, 54 ... tray, 55 ... Laser irradiation means, 60 ... piezoelectric device, 61 ... container body, 62 ... concave, 63 ... integrated circuit

Claims (8)

For an electronic device having a container having a void inside and having a void which communicates the void with the outside and further seals by melting and solidifying the sealing member A package,
A first metal film is formed on the outer peripheral surface of the sealing hole, and a second metal film is formed on at least a part of the outer peripheral surface of the sealing hole, The electronic device package, wherein the melting point of the second metal film is lower than the melting point of the first metal film.   The electronic device package according to claim 1, wherein the second metal film is formed on the first metal film.   2. The electronic device package according to claim 1, wherein the second metal film is formed on a peripheral surface outside the sealing hole where the first metal film does not exist.   The electronic device package according to claim 1, wherein gold is used as the first metal film, and a gold-tin alloy is used as the second metal film.   An electronic device comprising: the electronic device package according to any one of claims 1 to 4, the sealing member, and an electronic component disposed in a space of the container. .   The electronic device according to claim 5, wherein a gold-germanium alloy is used as the sealing member.   An electronic apparatus comprising the electronic device according to claim 6. A container having a void in the interior and having a sealing hole for communicating the void with the outside; a sealing member for sealing the sealing hole by solidifying after being melted; and the sealing member. An electronic component housed in the container in which the sealing hole is sealed, and a first metal film on the outer peripheral surface of the sealing hole and on the inner wall over the entire circumference. And a second metal film is formed on at least a part of the outer peripheral surface of the sealing hole, and the melting point of the second metal film is higher than the melting point of the first metal film. A low electronic device manufacturing method comprising:
Accommodating the electronic component in a void of the container;
A container setting step for setting the container so that the sealing hole faces upward;
A sealing member disposing step of disposing the sealing member on the sealing hole;
A first melting step for melting the second metal film;
A depressurization step of depressurizing the void of the container after the first melting step;
A second melting step for melting the sealing member;
Including
In the first melting step, in a state in which communication between the void of the container and the outside of the container is ensured, the sealing is performed in the sealing hole or in a peripheral portion of the sealing hole by the second metal film. A method for manufacturing an electronic device, comprising fixing a member.

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