JP2013110183A - Manufacturing method of electronic device and falling prevention member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an electronic device which reliably prevents a sealing member from being scattered by a gas discharged from a sealing hole with a simple method, and to provide a falling prevention member of the sealing member.SOLUTION: An electronic device has a container 2 having a sealing hole 37, a sealing member 38, and an electronic component 30 hermetically sealed in the container. A manufacturing method of the electronic device includes: a process where the sealing member is disposed on the sealing hole; a process where a falling prevention member 70, having a cone-shaped falling prevention hole 73 having an inverted conical inner wall 73b where a diameter of a lower opening 73a is larger than a diameter D of the sealing member and the inner diameter gradually increases toward the upper side, is placed so that the sealing member is positioned at the inner side of the lower opening; a decompression process; a heating process; and a melting process where the sealing member is melted.

Description

  The present invention relates to a method for manufacturing an electronic device in which a piezoelectric vibration element and other electronic components are accommodated in a container, and a drop-off preventing member.

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, the spherical sealing member for sealing the sealing hole formed in the container has a diameter of 0.5 mm or less, for example. It is extremely difficult to properly maintain the gaps between all the containers set and the cover.

JP 2003-158439 A JP 2011-129735 A

  The present invention has been made in view of the above, and a method for manufacturing an electronic device that can reliably prevent a sealing member from being scattered by a gas discharged from a sealing hole by a simple technique, and prevention of dropping. The object is to provide a member.

  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 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 of the container, and solidifying after melting. A sealing member for sealing the sealing hole, and an electronic component hermetically sealed in the container having the sealing hole sealed by the sealing member, and the sealing member is sealed with the sealing member. A method of manufacturing an electronic device including a sealing member arranging step of arranging on a stop hole, wherein the container is set so that the sealing hole faces upward, and a lower opening diameter is the sealing member The drop-off prevention member having a drop-prevention through-hole having an inner wall whose inner diameter gradually increases toward the top while holding the drop-off prevention member smaller than the diameter of the sealing member. The sealing member is positioned inside the lower opening of the hole. A stopper member disposing step of location, characterized in that it comprises a pressure reducing step for reducing the cavity of the container after the sealing member placing step and the stopper members arrangement step.

According to this configuration, when the gas inside the container is discharged from the sealing hole in the decompression step, even if the sealing member is lifted by the pressure, it falls before it passes over the upper opening of the through hole for preventing falling off. At the same time, it can be guided by the inner wall of the tapered dropout prevention hole and returned to the sealing hole.
The range of the distance that the sealing member floats during decompression can be assumed by the weight of the sealing member, the volume of the space in the container, the strength of vacuum suction for decompression, etc. The axial length of the dropout prevention hole can be set appropriately.

  [Application Example 2] The present invention is the drop-off preventing member used in the method for manufacturing an electronic device according to Application Example 1, wherein the sealing hole is formed on an outer surface of the container and is formed from the sealing member. A recess having a large opening area, and a small hole that is formed through the inner bottom surface of the recess and is closed when the sealing member is seated, and the diameter of the sealing member is D, The inner diameter of the lower opening of the drop-off preventing through hole is d1, and the inner diameter of the recess is d2, so that the relationship φd1 <φd2 + φD is satisfied.

  According to this configuration, even when the inner diameter of the lower opening of the dropout prevention hole is larger than the inner diameter of the recess, the sealing member is not caught by the step formed there.

  Application Example 3 In the application example 2, the present invention is characterized in that at least one light transmission opening for recognizing an image of the container is provided on a side of the drop-off preventing through hole.

  In determining the irradiation position of the laser spot when the sealing member is melted with the laser beam, the shape of the container and the shape of a part of the container are clues (marks). In order to recognize this mark with a camera, it is convenient to provide a light-transmitting opening in the drop-off prevention member.

  [Application Example 4] In the present invention, in the application example 3, the drop-off prevention member includes a large-area opening that exposes a part of the container, and the thin-walled part provided in the large-area opening has the drop-off prevention member. A through hole is formed so as to penetrate, and the light transmitting opening is formed in the vicinity of the thin portion.

  According to this configuration, since the thin-walled portion and the light-transmitting opening are provided and the through-hole for preventing dropout is formed on the thin-walled portion, there is a portion that blocks the illumination light when the position of the sealing member is recognized by the camera. As a result, the sharpness of the obtained image can be increased.

It is the schematic plan view which showed one Embodiment of the piezoelectric device as an example of the electronic device of this invention. FIG. 2 is a schematic sectional view taken along line XX in FIG. 1. It is a bottom view of FIG. It is a flowchart explaining the manufacturing method of the electronic device which concerns on this invention. (A) And (b) is a longitudinal cross-sectional view which shows the state which mounted the crystal vibration element in the container main body, and the figure which shows the procedure which closes a container main body opening with a cover body. It is a figure explaining a drop-off prevention member arrangement | positioning process, a sealing member arrangement | positioning process, and a sealing process. It is principal part sectional drawing which shows the relationship between a sealing hole and a sealing member. It is sectional drawing to which the sealing hole and the through hole for drop-off prevention were expanded. It is the figure which showed an example of the temperature profile in a pressure reduction process. (A) (b) is sectional drawing which shows the procedure which fuses a sealing member by irradiating a laser beam. (A) And (b) is the outer surface side perspective view which shows the principal part structure of the drop-off prevention member which concerns on other embodiment of this invention, and its YY sectional drawing. (A) is a schematic plan view which shows the structure of different embodiment of the piezoelectric device of this invention, (b) is a ZZ line schematic sectional drawing of (a). 1 is a diagram illustrating a schematic configuration of a digital cellular 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 a first embodiment of a piezoelectric device as an example of an electronic device of the present invention, FIG. 1 is a schematic plan view thereof, and FIG. 2 is a schematic cross-sectional view taken along line XX of FIG. FIG. 3 and FIG. 3 are bottom views of FIG.
In these drawings, the piezoelectric device 1 shows a piezoelectric vibrator as an example, 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 dimensions of the container 2 are, for example, 5 mm in length, 3.2 mm in width, and 0.8 mm in height.

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, and a second laminated substrate 12 having a hole in a part of the first laminated substrate 11. The ring-shaped third laminated substrate 13 and the mounting terminal 17 formed on the outer surface of the first laminated substrate 11 are formed thereon.
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 mounting terminals 17 having a corresponding relationship to supply a driving voltage. A conductive adhesive 16, 16 is applied on each of the electrode portions 15, 15, and a base 31 of the piezoelectric vibration element 30 is placed on the conductive adhesive 16, 16, so that the conductive adhesive 16 16 are 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 the present 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 in parallel from the base 31 in a bifurcated manner toward the right in the drawing. A so-called tuning fork type piezoelectric vibration element having a shape like a tuning fork is used.
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.

Further, in the vicinity of the center of the bottom surface of the container body 3, the first and second through holes 37a and 37b are continuously formed in the two laminated substrates 11 and 12 constituting the bottom plate of the container body 3, respectively. A sealing hole 37 is provided as a hole. Of the two through-holes constituting the sealing hole 37, the outer second through-hole (recess) 37b is more than the first through-hole (small hole) 37a opened inside the container body. Concentric with a large inner diameter. As a result, the sealing hole 37 is an opening having a stepped portion 40, and preferably, the stepped portion of the second through hole 37b and the inner peripheral surface of the first through hole 37a are sealed as described later. A metal ball (for example, a gold germanium alloy (Au / Ge)) that is the member 38 is covered with a metal having good wettability, such as gold plating, by being formed on a predetermined underlayer. .
That is, after fixing the piezoelectric vibration element 30 in the container body 3, a sealing member (metal sealing member) 38 is melt-filled in the sealing hole 37, so that the container body 3 is hermetically sealed. Seal.

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. An arbitrary metal material can be used as the sealing member.
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 in the vicinity of the right end portion in the drawing. Yes. 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 container body 3 of the piezoelectric device 1 is sealed with a sealing member 38 made of a gold germanium alloy (Au / Ge). For this reason, in the process of mounting the piezoelectric device 1 after sealing, when heat is applied, 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 electronic device manufacturing method of the present invention has the following characteristic configuration.
That is, in the present invention, the container 2 having the void S inside and the sealing hole 37 for communicating the void with the outside of the container is melted with the container 2 having the outer wall (laminated substrate 11, 12 or lid 20). An electron having a sealing member 38 that seals the sealing hole 37 by solidifying later, and an electronic component 30 that is hermetically sealed in a container whose main hole is sealed by the sealing member. The present invention relates to a device manufacturing method.
A characteristic configuration of the manufacturing method according to the present invention is that a container setting step for setting the container 2 on an arbitrary support means such that the sealing hole 37 faces upward, and a sealing member 38 on the sealing hole 37 are arranged. And a mortar-shaped sealing member having an inverted conical inner wall 73b in which the inner diameter d1 of the lower opening 73a is larger than the diameter D of the sealing member and the inner diameter gradually increases toward the upper side. The drop-off prevention member 70 having the drop-off prevention through-hole 72 including at least a part of the drop-off prevention hole 73 is kept at a distance t from the outer surface of the container (or the sealing member) smaller than the diameter D of the sealing member. While the sealing member dropping prevention hole 73 is disposed so that the sealing member is positioned inside the lower opening 73a, the container 2 and the dropping prevention member 70 are arranged in the chamber. By depressurizing the container A depressurizing step of depressurizing the place S, a heating step of heating the container 2, a melting step of melting the sealing member 38 in a state where the void is depressurized, a step of opening the chamber to the atmosphere after the melting step, It is in the point which has.
In addition, a sealing member arrangement | positioning process and a drop-off prevention member arrangement | positioning process can replace order. That is, the sealing member arrangement step may be performed after the drop prevention member arrangement step is preceded.

Next, FIG. 4 is a flowchart for explaining an electronic device manufacturing method according to the present invention, and FIGS. 5A and 5B are longitudinal sectional views showing a state in which a crystal resonator element is mounted in a container body, and FIG. 6 is a diagram illustrating a procedure for closing the container main body opening with a lid, FIG. 6 is a diagram illustrating a drop-off prevention member arranging step, a sealing member arranging step, and a sealing step, and FIG. 7 is a diagram illustrating a sealing hole and a sealing step. It is principal part sectional drawing which shows the relationship with a stop member, and FIG. 8 is explanatory drawing which expanded the sealing hole and the through-hole.
In FIG. 4, 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 step of preparing the container body 3 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.
In addition, each through-hole 37a, 37b may be a circular hole or a non-circular (polygonal or other irregular shape) 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.

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. 5A, 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 adjustment method based on this mass reduction method, the initial frequency of the piezoelectric vibration element 30 is made lower 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. 5B, for example, in the chamber 50 for forming a nitrogen atmosphere, the lid 20 is placed on the container placement table 54 on the support table 53, and the top The container body 3 is placed upside down so that the brazing material 33 mentioned above comes into contact with the lid 20, and the inside of the chamber 50 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 50.
Through the above steps, the process of housing the piezoelectric vibration element in the container 2 in an unsealed state is completed.

Next, the container 2 in which the piezoelectric vibration element 30 is accommodated and bonded in the internal space S 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 20) containing a piezoelectric vibration element inside a vacuum chamber 51 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. In this example, the container 2 is set so that the sealing holes 37 face upward in a plurality of container receiving recesses 54 a formed on the upper surface of the container mounting table 54, and the container mounting table 54 is covered so as to cover each container. The sealing member 38 set on the sealing hole 37 is melted by the laser light L through the through hole 72 for preventing the dropout formed in the dropout preventing member 70 with the dropout preventing member 70 disposed thereon.
The vacuum chamber 51 has a configuration in which the upper surface opening of the chamber body 51a is closed by the glass wall 51b, and the laser light L from the laser irradiation means 55 arranged opposite to the glass wall 51b is sealed in each container. It is comprised so that it can irradiate toward the sealing member 38 mounted in the hole 37. FIG. The laser irradiation means 55 is configured to be movable in the X and Y directions along a plane parallel to the glass wall 51b. Further, a camera 56 for image inspection and a ring illumination means 58 for irradiating the periphery of the sealing hole are incorporated in the casing 56 that supports the laser irradiation means 55. Light from a laser light source (not shown) is irradiated onto the sealing member 38 via a prism 59 disposed in the housing 56. The camera 57 obtains information about the optimum position for irradiating the laser beam L by capturing images of the sealing hole and its surroundings via the prism 59. The ring illumination means 58 illuminates the inside of the drop-off preventing through hole 72 so that the camera can capture a clear image.

In the sealing member arranging step of step S6, a spherical sealing member 38 made of an alloy of gold and germanium or an alloy of gold and tin is arranged in the sealing hole 37 provided on the bottom surface of the container 2. To do. The arrangement of the sealing member 38 can be performed using the shape of the inner periphery of the sealing hole 37. That is, the first through hole (small hole) 37a on the inner space S side and the second through hole (recess) 37b concentric (external side) larger than the through hole 37a communicate with each other. By using the step shape of the sealing hole 37 and placing the container 2 so that the inner space S side is on the lower side, a spherical sealing member 38 inserted from the outer side of the sealing hole 37 is formed. It is held and arranged at the stepped portion in the sealing hole 37 (see FIG. 7).
In addition, after setting the drop-off prevention member 70 on each container as described later, the sealing member 38 may be disposed in the seal hole 37 from the through-hole 72 for drop-off prevention.

As shown in FIG. 7, the sealing hole 37 in which the spherical gold germanium alloy (Au / Ge) alloy sealing member 38 is arranged has an inner first through hole (having a predetermined inner diameter n1). (Small hole) 37a and a second through hole (recess) 37b which is provided in communication with the first through hole 37a and has an inner diameter n2 larger than the first through hole 37a and which opens to the outside. It has. The diameter n3 of the spherical gold germanium alloy (Au / Ge) 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. Yes.
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.

Next, in step S7, a drop prevention member arranging step is performed.
6 and 8, in the dropout prevention member arranging step, the dropout prevention member 70 having the dropout prevention through hole 72 has a positional relationship in which the dropout prevention through hole 72 communicates with the sealing hole 37. And placed above the container. The drop-off prevention member 70 is disposed such that the distance t between the lower surface thereof and the upper surface of the container (or the upper portion of the sealing member) is smaller than the diameter D of the sealing member. For this reason, it is possible to prevent the sealing member 38 from entering or leaving the interval t.
The dropout prevention through-hole 72 has a same-axis-shaped sealing member dropout prevention hole 73 in at least a part of its axial direction.
A sealing member dropout prevention hole (hereinafter referred to as a dropout prevention hole) 73 has an inverted conical shape (conical shape) in which the inner diameter d1 of the lower opening 73a is larger than the diameter D of the sealing member and the inner diameter gradually increases toward the upper side. ) Having an inner wall 73b.
When setting the drop-off prevention member 70 so as to face the sealing hole forming surface of the container, the drop-off prevention through hole 72 (drop-off prevention hole 73) and the sealing hole (particularly, the first through hole 37a). ) Are positioned so that they face each other in communication. As a result, the sealing member 38 (first through hole 37a) seated on the opening periphery of the first through hole 37a has a lower opening of the drop prevention hole 73 when the drop prevention through hole 72 is viewed in plan view. It will be located inside 73a. Here, “when the plan view of the dropout prevention through hole 72 is located inside the lower opening 73a of the dropout prevention hole 73” means that the sealing member is inside (inside) the inner peripheral edge of the lower opening 73a. This means that the entire outer contour of the sealing member (first through hole 37a) can be visually recognized when viewed from above. Therefore, in FIG. 8 which is a longitudinal sectional view, it does not necessarily mean that a part of the sealing member 38 seated on the opening peripheral edge of the first through hole 37a enters the drop-off preventing through hole 72. In short, the positional relationship between the first through-hole 37a and the drop-off prevention hole 73 is such that the sealing member 38 lifted by the gas discharged from the internal space S of the container in the decompression step described later is placed in the drop-off prevention hole 73. If it is configured to be able to enter from the opening 73a, and return to the lower opening 73a after being guided by the inner wall 73b when it decelerates and drops after entering, and finally returns to the state seated on the sealing hole 37 Good.

  In the example shown in FIG. 8, the inner diameter of the lower opening 72a of the drop-off prevention through hole 72 does not match the inner diameter of the lower opening 73a of the drop-off prevention hole 73, and the lower opening 72a and the lower opening 73a A non-tapered (substantially vertical) inner wall 72b is interposed therebetween. The non-tapered inner wall 72b may be generated due to an accuracy error or the like when the through-holes 72 for preventing drop including the drop-out preventing holes 73 are processed by a drill or the like. In this case, when the stepped portion U is formed between the outer surface of the container corresponding to the outer peripheral edge of the sealing hole 37 (second through hole 37b) and the inner wall 72b, and the width of the stepped portion U is excessively large, The sealing member 38 that once floated in the drop-off prevention hole and then dropped along the tapered inner wall 73b of the drop-off prevention hole is caught on the stepped portion U and falls onto the first through hole 37a. There is a risk of disappearing.

In order to deal with such a problem, the relationship between the diameter D of the sealing member 38, the inner diameter d1 of the lower opening 73a (72a) of the dropout prevention hole, and the inner diameter d2 of the second through hole 37b is expressed by the following equation. It is effective to specify as follows.
φd1 <φd2 + φD
By configuring in this way, the width of the stepped portion U can be made sufficiently smaller than the diameter of the sealing member, and the sealing member can be prevented from being caught on the stepped portion.
Although it is ideal that the inner diameter d1 of the lower opening 73a (72a) of the dropout prevention hole and the inner diameter d2 of the second through hole 37b coincide, the container 2 moves in the recess 54a of the container mounting table 54. Therefore, it is preferable to configure the inner diameter d1 larger than the inner diameter d2.

In addition, the dimension example of each part in this embodiment is as follows, for example.
First, the diameter D of the sealing member 38 is 0.22 mm, the thickness T of the drop-off prevention member 70 (the axial length of the drop-off prevention through hole 72) is 0.6 mm, and the diameter d1 of the lower opening 73a is The inner diameter d2 of the second through hole 37b is 0.4 mm. Moreover, the space | interval t between the upper surface (sealing hole formation surface) of the container 2, or the sealing member and the lower surface of the drop-off prevention member 70 is about 0.1 mm. The reason why the gap t is provided between the upper surface of the container 2 and the lower surface of the drop-off prevention member 70 is that when both are in contact with each other, the drop-off prevention member is located above the heat of the container heated from below in the decompression step described later. This is to prevent 70 from being taken away and the heating efficiency of the container from being lowered.

  Here, in order to manage and arrange the gap t between the outer bottom surface (sealing member) of the container 2 and the drop-off prevention member 70 within a range satisfying the relationship of t <D, although not illustrated, A spacer having the same thickness as the gap t between the outer bottom surface of the container 2 and the drop-off prevention member 70 may be provided in a region different from the region where the recess 54 a of the container mounting table 54 is provided.

  The thickness T of the drop-off prevention member 70, that is, the axial length of the drop-off prevention through-hole 72 is determined by the upper opening of the drop-off prevention through-hole 72 when the sealing member jumped from the first through-hole 37a by the exhausted gas pressure. It is set to the extent that it does not scatter outside. There are various jumping patterns (jumping distance and direction) of the sealing member during decompression, but there is a limit on the jumping height, so the axial length of the drop-off prevention through hole is set to exceed this limit height. By doing so, scattering from the upper opening can be prevented. Moreover, once the sealing member returns into the dropout prevention hole, it is guided by the tapered inner wall and returned to the sealing hole.

Specifically, even if the sealing member 38 is lifted through a trajectory as indicated by a chain line arrow in FIG. 8, after hitting the inner wall 73 b, it falls along the inner wall or bounces off the inner wall, and the first penetration It can return on the hole 37a.
The range of the distance that the sealing member floats during decompression can be assumed within the predetermined range depending on the weight of the sealing member, the volume of the space in the container, the strength of vacuum suction for decompression, etc. The axial lengths of the through hole and the dropout prevention hole can be set appropriately.

The material of the drop-off prevention member 70 is preferably the same material as that of the container mounting table in order to eliminate the difference in linear expansion from the container mounting table that holds the container. Specifically, for example, titanium or the like is used. If there is a difference in thermal expansion between the container mounting table and the drop-off prevention member in the step of heating the container, the position of the drop-off preventing through hole and the position of the container-side sealing hole 37 set on the container mounting table This is because a misalignment occurs and the alignment state deteriorates.
The taper angle of the inner wall of the dropout prevention hole 73 is set so that the sealing member 38 can easily fall along the wall and return to the first through hole 37a. Specifically, the angle θ formed by the two inner walls facing each other in the longitudinal sectional view of the drop-off prevention hole 73 is set to be 70 to 150 degrees, preferably 80 to 140 degrees. The range of the angle θ is also a value at which the laser beam irradiated in the sealing member melting step described later is not hindered by the inner wall 73b of the dropout prevention hole 73.

Note that the sealing member may be arranged in the sealing hole 37 after the dropping prevention member is arranged by performing the sealing member arranging process after the dropping prevention member arranging process. That is, in this case, since the sealing hole 37 is located inside the drop-off prevention hole 73 formed in the drop-off prevention member 70, the sealing member held by tweezers or mechanically held Is inserted from the upper opening of the drop-off prevention hole 73, the sealing member falls along the tapered inner wall of the drop-off prevention member, and is securely seated on the first through hole 37a constituting the sealing hole. be able to. On the other hand, if the sealing member is inserted into a small sealing hole having a diameter of about 0.4 mm before setting the drop-off preventing member on the container, it is clear that workability is deteriorated. . On the other hand, if the sealing member is inserted using the drop prevention hole having a large upper opening diameter after setting the drop prevention member, workability is greatly improved.
Regardless of which process is preceded, the container mounting table on which the container is set can be moved by moving the container mounting base on the container in which the sealing member is disposed in the sealing hole. The sealing member does not fall when it is set to or other handling is performed.

Next, a decompression step is performed in step S8.
In the depressurization step of step S8, the internal space S of the container 2 is heated while depressurizing by depressurizing the inside of the vacuum chamber 51, and is heated via the gap 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. 6, the container 2 in a state where the sealing member 38 is disposed on the sealing hole 37 is disposed in the vacuum chamber 51, and the interior of the vacuum chamber 51 is not illustrated. A vacuum is evacuated by a vacuum evacuation means, and a high vacuum state is preferable.

In the heating step of heating the container simultaneously with the start of decompression or after the start of decompression, for example, the container is heated by a heater (not shown) via the container mounting table 54 that accommodates the container.
FIG. 9 shows an example of a temperature profile in the decompression step. That is, the inside of the vacuum chamber 51 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 (melting step) is performed for T3 time (for example, 20 minutes) while maintaining the temperature and pressure in the vacuum chamber 51. 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. It is possible to effectively expel the gas component. Then, the laser beam L is irradiated from the laser irradiation means 55 toward the sealing member 38 to melt and solidify the sealing member 38, thereby completely closing the through hole 37 (S9, S10).
In other words, the spherical gold germanium alloy (Au / Ge) alloy sealing member 38 is irradiated with laser light L as shown in FIG. 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.
In the present invention, at least during the decompression step of step S8, as shown in FIGS. 6 and 8, the drop-off prevention member 70 is disposed with a gap parallel to the outer bottom surface where the sealing hole 37 of the container 2 is formed. To do. FIG. 6 shows an example in which a container mounting table (tray) 54 provided with a recess 54a in which a plurality of containers 2 can be set with the sealing holes 37 facing upward is shown in order to increase manufacturing efficiency. ing.

Further, as described above, the dropout prevention member 70 is formed with the dropout prevention through hole 72 at a position directly corresponding to the sealing hole 37, and the dropout prevention through hole 72 tapers upward. A mortar-shaped drop-off preventing hole 73 whose inner diameter is expanded is included.
For this reason, the sealing member 38 that protrudes upward from the sealing hole 37 by the pressure of the gas discharged from the internal space S to the outside in the process of degassing inside the container 2 causes the lower opening 73a ( 72a) enters the drop-off prevention hole 73, falls inside the drop-off prevention hole and returns to the sealing hole 37 before jumping out from the upper opening of the drop-off prevention hole. At this time, since the inner wall 73b of the dropout prevention hole 73 is tapered so that the sealing member can easily fall, the sealing member can surely fall into the sealing hole, and the laser beam can be used as it is. Can shift to the step of melting the sealing member.
In other words, since the sealing member 38 that exhibits the behavior of popping out of the sealing hole 37 can be returned to the predetermined position in the sealing hole 37 by the drop-off preventing member 70 in a shorter time, the decompression time Can be shortened and work efficiency can be improved.
After degassing the inside of the container 2 in the decompression step of step S8, for example, laser light is applied to the spherical sealing member 38 disposed in the sealing hole 37 with the drop-off preventing member set. The sealing member 38 is melted by irradiation. As a result, the melted sealing member 38 wets and spreads on the metal film 45, and the sealing of the sealing hole 37 by the sealing member 38 can be strengthened (step S9).

FIGS. 10A and 10B are cross-sectional views showing a procedure for melting the sealing member by irradiating the laser beam, and the drop-off preventing member 70 is not removed even in the step of irradiating the laser beam.
As shown in FIG. 5B, after the molten sealing member 38 is sufficiently filled in the sealing hole 37, the molten sealing member 38 is cooled and cured (solidified) by stopping the laser beam irradiation. (Step S10). Then, the inside of the vacuum chamber is opened to the atmosphere (step S11), the sealing process from step S6 is completed, and the container mounting table 54 on which the plurality of piezoelectric devices 1 (containers 2) are mounted is taken out from the vacuum chamber. Then, a series of manufacturing steps is completed.

  According to the method for manufacturing the piezoelectric device 1 of the above embodiment, in the decompression step (step S8) in which degassing is performed from the internal space S of the container 2, sealing is performed by the pressure of the gas discharged from the internal space S to the outside. The spherical sealing member 38 that is about to jump out of the container from the hole 37 can be prevented from scattering by the drop-off prevention hole 73 of the drop-off prevention member 70, so that the piezoelectric device 1 of the piezoelectric device 1 by the sealing member 38 jumping out of the sealing hole 37 Sealing failure can be prevented. Therefore, the piezoelectric vibrating device 1 in which the internal space S of the container 2 to which the piezoelectric vibrating element is bonded is reliably hermetically sealed can be manufactured with high yield.

Further, a drop-off prevention hole 73 is provided in at least a part of the through-hole 72 for drop-off prevention, and the inner wall below the small-diameter lower opening and the upper opening of the large-diameter upper opening are provided. Since the inner wall has a configuration in which the inner diameter is not narrower than each opening, the inner wall of the drop-out preventing through hole 72 does not become an obstacle to the irradiation of the laser beam to the sealing member.
Further, in the method of the present embodiment, a sealing member 38 of a gold germanium alloy (Au / Ge) formed in a spherical shape is disposed in the through hole 37 formed in the bottom of the container body 3, and in the melting process. It is melted (mainly sealed).
The gold-germanium alloy (Au / Ge) sealing member 38 has a high melting point, but is easily oxidized, and an oxide film is easily formed on the surface. That makes it 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.

Next, FIGS. 11A and 11B are a top side perspective view and a YY cross-sectional view showing a main part configuration of a sealing member drop-off preventing member according to another embodiment of the present invention.
The sealing member drop-off preventing member 70 according to this embodiment includes a thin portion 82, a translucent opening 84 in a large area opening 80 having an opening area equal to or larger than the area of the container 2, And a structure in which a through hole 72 for drop-off prevention provided with a drop-out prevention hole 73 is formed in the thin wall portion 82 is characteristic.
It should be noted that the opening area and shape of the large-area opening 80 need only be configured so as to expose a part of the opposing surface of the opposing container, and may be narrower than the area of the opposing surface of the container.

The thin-walled portion 82 is a thin-walled and narrow strip-shaped plate-like portion that is disposed across two opposing inner walls of the large-area opening 80, and is configured to be thinner than the maximum thick-walled portion of the drop-off prevention member 70. Yes. In addition, a translucent opening 84 is formed through both sides of the thin portion 82. The translucent opening 84 is an opening for confirming the presence / absence of the container by the camera 57 and, when there is a container, an opening for exposing the mounting terminal 17 on the bottom surface of the container 2 disposed immediately below the container. . When the position of the sealing member 38 on the sealing hole 37 is recognized by the camera 57 shown in FIG. 6, the opening shape is set so that the shape of the mounting terminal 17, the position of the corner portion, and the like can be used as marks. ing. After recognizing the positional relationship between the sealing hole and the drop-off preventing through hole 72 using this mark as a clue, the sealing member is accurately irradiated with laser light.
Forming the thin portion 82 for forming the drop-off preventing through hole 72 is not essential in the process of irradiating the laser beam to melt the sealing member, but the mounting terminal in the light transmitting opening 84 is ring-illuminated. In order to reliably illuminate with the means 58 and improve the image quality of the image captured by the camera 57, it is preferable that there is no thick portion adjacent to the transparent opening 84. That is, by providing the thin portion 82 at the center of the large-area opening, there is no thick portion that obstructs illumination and imaging inside the transparent opening 84.
In the illustrated example, two light-transmitting openings 84 are provided, but the number and shape of the light-transmitting openings can be arbitrarily selected as long as the mounting terminals that serve as a reference for alignment by the camera can be exposed.

Next, FIG. 12A is a schematic plan view showing the configuration of a different embodiment of the piezoelectric device of the present invention. In the figure, the piezoelectric device 60 shows an example in which a piezoelectric oscillator is formed by using the piezoelectric vibration element 30, and portions having the same reference numerals as those in the first embodiment have a common configuration. The description will be omitted, and the difference will be mainly described.
FIG. 12B is a schematic cross-sectional view taken along the line ZZ of FIG. 12A, 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, but includes a piezoelectric vibration element, such as a piezoelectric oscillator or a filter as shown in FIG. 14, regardless of its name, and is sealed with a lid. Applicable to any piezoelectric device of the configuration.

FIG. 13 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 FIG. 13, 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, and an integrated circuit as a control unit connected to the modulation and demodulation unit of the transmission / reception signal 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. 12 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.
Moreover, in the said embodiment, although the sealing hole was formed in the container main body side, the sealing method by this invention is applicable also to the electronic device provided with the sealing hole in the cover body 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, S ... Internal space, 3 ... Container main body, 11 ... 1st laminated substrate, 12 ... 2nd laminated substrate, 13 ... 3rd laminated substrate, 15 ... Electrode part, 16 ... Conductive adhesive, 17 ... mounting terminal, 30 ... piezoelectric vibration element (electronic component), 31 ... base, 33 ... brazing material, 34, 35 ... vibrating arm, 37 ... sealing hole, 37a ... first through hole ( (Small hole), 37b ... second through hole (recess), 38 ... sealing member, 40 ... stepped portion, 50 ... chamber, 51 ... vacuum chamber, 51a ... chamber body, 51b ... glass wall, 52 ... weight, 53 ... support table, 54 ... container mounting table, 55 ... laser irradiation means, 56 ... housing, 57 ... camera, 58 ... ring illumination means, 59 ... prism, 60 ... piezoelectric device, 61 ... container body, 62 ... recess, 63... Integrated circuit, 70. Hole, 72a ... lower opening, 72b ... inner wall, 73 ... drop-off prevention hole, 73a ... lower opening, 73b ... inner wall, 108 ... microphone, 109 ... speaker, 101 ... controller, 102 ... input / output unit, 103 ... information storage means, 105 ... Temperature compensated crystal oscillator, 107 ... Transmitter, 106 ... Receiver, 110 ... Mobile phone device

Claims (4)

A container having a void inside and a sealing hole for communicating the void with the outside of the container; a sealing member for sealing the sealing hole by solidifying after melting; and the sealing member An electronic component hermetically sealed in the container having the sealing hole sealed therein, and including a sealing member disposing step of disposing the sealing member on the sealing hole. A manufacturing method comprising:
A container setting step for setting the container so that the sealing hole faces upward;
A drop-off prevention member having a drop-off prevention through-hole having an inner wall whose lower opening diameter is larger than the diameter of the sealing member and gradually increases toward the upper side is smaller than the diameter of the sealing member. A drop-off prevention member disposing step of disposing the sealing member so as to be located inside a lower opening of the drop-off prevention through-hole while holding,
A decompression step of decompressing the void of the container after the sealing member placement step and the drop-off prevention member placement step;
The manufacturing method of the electronic device characterized by the above-mentioned. The drop-off preventing member used in the method for manufacturing an electronic device according to claim 1,
The sealing hole is formed in a recess formed on the outer surface of the container and having a larger opening area than the sealing member, and is formed through the inner bottom surface of the recess and is closed when the sealing member is seated. A small hole,
When the diameter of the sealing member is D, the inner diameter of the lower opening of the drop-off preventing through hole is d1, and the inner diameter of the recess is d2,
φd1 <φd2 + φD
A dropout prevention member characterized by being configured to satisfy the above relationship.   The drop-off prevention member according to claim 2, further comprising at least one light-transmitting opening for recognizing an image of the container on a side of the drop-off prevention through hole. The drop-off prevention member includes a large-area opening that exposes a part of the container, and the through-hole for drop-off prevention is formed through a thin portion provided in the large-area opening.
4. The dropout prevention member according to claim 3, wherein the light transmission opening is formed in the vicinity of the thin portion.

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