JP2010103802A - Electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an electronic device which is miniaturized and durable to use for a long time. <P>SOLUTION: A package 10 is composed of: a substrate 11; a first frame-like sidewall 13 which is joined on the substrate 11; and a second frame-like sidewall 15 to be joined on the first frame-like sidewall 13. Castellation 12 which reaches from a lower surface 11a to an upper surface 11b is formed on a side 11c of the substrate 11, and castellation 14 which reaches from a lower surface 13a to an upper surface 13b is formed on a side 13c of the first frame-like sidewall 13, and castellation 16 which reaches from a lower surface 15a to an upper surface 15b is formed on a side 15c of the second frame-like sidewall 15. Then, the depth of the castellation 16 is formed so as to be shallower than the depth of the castellation 12. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to an electronic device such as a piezoelectric oscillator, and is particularly suitable for obtaining long-term electrical quality without causing an increase in size.

In recent years, piezoelectric oscillators have been used in many fields from communication devices such as mobile phones to consumer devices such as quartz watches due to their frequency stability, small size and light weight, robustness, and low price. In particular, a temperature compensated piezoelectric oscillator (TCXO) that compensates for the frequency temperature characteristics of a piezoelectric vibrator is widely used in mobile phones and the like that require frequency stability.
Patent Document 1 discloses a temperature-compensated crystal oscillator that is miniaturized and surface-mounted.
FIG. 6 is an exploded perspective view thereof. FIG. 6A is a metal cap, FIG. 6B is a crystal resonator element, and FIG. 6C is a metal cap removed so that the inside can be seen. It is a perspective view of a temperature compensation type crystal oscillator.
As shown in FIG. 6, a temperature-compensated crystal oscillator 70 includes a multilayer ceramic substrate 72 that forms a sealing chamber 71, a circuit element 73 that is disposed in the sealing chamber 71 and forms an oscillation circuit and a compensation circuit, and a sealing chamber. The quartz crystal vibration element X fixed to a multilayer ceramic substrate (hereinafter simply referred to as “substrate”) 72 in 71 and a metal cap 76 welded to a Kovar seal ring 75 provided on the upper surface of the substrate 72. It is configured. Here, the crystal resonator element X is fixed on a pair of cages 77 and 78 provided in the sealing chamber 71 via a conductive paste.

The cages 77 and 78 are made of a conductive elastic material, and have distal end portions 77a and 78a and proximal end portions 77b and 7.
8b, and the tip portions 77a and 78a are formed in a substantially hook shape. Cage 7
7 and 78, only the base end portions 77b and 78b are fixed on the substrate 72, and the tip end portion 77a thereof.
, 78 a are floating from the substrate 72. The lead electrodes 75c and 75d connected to the excitation electrodes 75a and 75b of the crystal resonator element X are fixed to the tip portions 77a and 78a via conductive paste, respectively. If the crystal resonator element X is directly fixed on the substrate 72, a minute strain generated in the substrate 72 by seam welding affects the crystal resonator element X, causing variations in the frequency of the crystal resonator element X. Therefore, when the frequency is to be highly accurate, the cage 77 is used as described above.
, 78, the crystal vibrating element X is fixed to the substrate 72.
The spring function of a and 78a absorbs minute distortion of the substrate 72 caused by seam welding and reduces the influence on the crystal resonator element X.

Patent Document 2 discloses a crystal oscillator including a test terminal having a DLD characteristic (drive level characteristic). FIG. 7A is a perspective view in which the package 81 is turned upside down. A pair of DLD characteristic test terminals 86 and 86 are provided on the bottom surface of the package 81, a power supply (Vcc) input terminal electrode 82, and a GND terminal electrode. 83, an OUT terminal electrode 84, and a Cont terminal electrode 85. The pair of test terminal electrodes 86 and 86 are electrically connected to the terminals A and B drawn from the switch 98 shown in FIG. The switcher 98 includes analog switches 95 and 96 and an inverter 97. The terminal C is connected to the power input terminal electrode 82 of the crystal oscillator. When testing the crystal resonator, if the power input terminal electrode 82 is grounded, the output of the inverter 97 becomes “H level” and the analog switch 96 is “ON”.
Thus, the test terminal electrodes 86 and 86 of the package 81 connected to the terminals A and B and the blank electrode 93 are electrically connected. Therefore, the DLD characteristic test can be performed by using the test terminal electrodes 86 and 86.
During operation of the crystal oscillator, a voltage is applied to the power input terminal electrode 82, so that the terminal C is “
H level ”. For this reason, the analog switch 95 is turned “ON”, the blank electrode 93 is connected to the vibrator connection terminal electrode 92 of the LSI 91, and the crystal oscillator enters an oscillation operation state. At this time, since the output of the inverter 97 becomes “L level”, the analog switch 96 becomes “OFF”, and the test terminal electrodes 86 and 86 and the blank electrode 5 are electrically disconnected.
Japanese Utility Model Publication No. 7-16413 JP 2001-102870 A

By the way, the piezoelectric oscillator disclosed in Patent Document 1 or 2 adheres a crystal vibration element not covered by a package to a cage provided in a multilayer ceramic package or a stepped portion in the package via a conductive adhesive. The configuration is fixed.
However, the piezoelectric oscillator having such a conventional configuration is small (for example, 7.0 × 5.0 ×
1.5 mm), and when used in a temperature compensated piezoelectric oscillator that guarantees electrical quality over a long period of time (for example, 10 to 20 years), the solder in the package is subject to repeated temperature changes or aging changes. Gas is generated from electronic parts. The gas is the substrate surface of the crystal resonator element,
There has been a problem that the frequency is changed by adhering to an electrode or the like, and the oscillation frequency may not satisfy the required standard.
The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide an electronic device that is small in size and can obtain long-term quality.

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 First and second main surfaces, side surfaces continuous with the first and second main surfaces, and a first surface that reaches the second main surface from the first main surface to the side surface. A substrate having a notch, a frame-shaped side wall disposed on the substrate and having a second notch extending from the upper surface to the lower surface on a side surface continuous with the upper surface and the lower surface, and the substrate and the frame-shaped side wall A piezoelectric vibrator housed in a space and an electronic component housed in a space made up of the substrate and the frame-shaped side wall, and the depth of at least a part of the second notch is the first. The electronic device is shallower than the depth of the notch.

By configuring the depth of a part of the second notch formed on the frame-shaped side wall disposed on the substrate to be shallower than the depth of the first notch formed on the substrate, the strength of the frame-shaped side wall is increased. Without lowering
It is possible to reduce the wall thickness and increase the internal space.
This makes it possible to mount a hermetically sealed piezoelectric vibrator inside the electronic device, so that the electronic device can maintain electrical quality for a long period of time without increasing the size of the electronic device. Can be configured.

[Application Example 2] The electronic device according to Application Example 1 is characterized in that at least the first cutout portion is plated out of the first cutout portion and the second cutout portion.

If at least the first cutout portion is plated out of the first cutout portion and the second cutout portion, the lid body is sealed when the lid body is sealed in the space formed by the substrate and the frame-like side wall. A short circuit with the first notch can be prevented.

Application Example 3 The electronic device according to Application Example 1, wherein the space is filled with an inert gas or is in a vacuum state, and the space is sealed with a lid.

By injecting an inert gas into the space formed by the substrate and the frame-shaped side wall and forming an electronic device hermetically sealed with a lid, electronic components, connection conductors, electrode terminals, etc. accommodated in the space As a result, it is possible to construct an electronic device that can withstand long-term use.

Application Example 4 The electronic device according to Application Example 1 is characterized in that resin is injected into the space to seal the space.

By constructing an electronic device in which the space formed by the substrate and the frame-shaped side wall is hermetically sealed with resin, the electronic components, connection conductors, electrode terminals, etc. accommodated in the space are protected from vibration, impact, oxidation, etc. In addition, there is an effect that an electronic device with more stable quality can be configured.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the present embodiment, a piezoelectric oscillator will be described as an example of an electronic device.
FIG. 1 is a schematic diagram showing the internal configuration of a piezoelectric oscillator according to an embodiment of the present invention.
1A is a plan view, FIG. 1B is a cross-sectional view taken along the line Q-Q, FIG. 1C is a composite view of a cross-sectional view taken along the left side of the left half and the right half of FIG. 2A and 2B are schematic views showing the external configuration of the piezoelectric oscillator of the present embodiment, in which FIG. 2A is a side view and FIG. 2B is a bottom view.
The piezoelectric oscillator 1 of the present embodiment includes a laminated ceramic package (hereinafter simply referred to as “package”) 10 in which ceramics are laminated as an airtight container. The package 10 includes a substrate 11, a first frame-like side wall 13 bonded on the substrate 11, and a first frame-like side wall 13.
It consists of the 2nd frame-shaped side wall 15 joined on the top. On the upper surface 15b of the second frame-shaped side wall 15,
A metal (Kovar material) seal ring 18 is joined.

The substrate 11 is made of a plate-like ceramic having a first main surface (lower surface) 11a, a second main surface (upper surface) 11b, and a side surface 11c continuous with the lower surface 11a and the upper surface 11b. On the side surface 11c of the substrate 11, as shown in FIG.
A castellation (first notch) 12 reaching 1b is formed.
As shown in FIG. 1B, the first frame-shaped side wall 13 includes a lower surface 13 a and a side surface 13 c continuous with the upper surface 13 b and is disposed on the substrate 11. On the side surface 13c of the first frame-like side wall 13, as shown in FIG. 1C, a castellation (from the lower surface 13a to the upper surface 13b)
A first notch 14) is formed.
As shown in FIG. 1B, the second frame-shaped side wall 15 also includes a lower surface 15a and a side surface 15c continuous with the upper surface 15b, and is disposed on the first frame-shaped side wall 13. Second frame-like side wall 15
As shown in FIG. 1C, a castellation (second notch portion) 16 reaching the upper surface 15b from the lower surface 15a is formed on the side surface 15c.
As will be described later, the piezoelectric oscillator 1 of the present embodiment is characterized in that at least the depth of the castellation 16 formed on the second frame-shaped side wall 15 is shallower than the depth of the castellation 12 formed on the substrate 11. There is. Here, if the castellation has a semi-cylindrical shape, the radius of the castellation corresponds to the depth.

A packaged piezoelectric vibrator 20 and various electronic components 25 and 26 are accommodated in the interior (space) of the package 10. The piezoelectric vibrator 20 and the various electronic components 25 and 26, for example, provide voltage. A control type temperature compensated piezoelectric oscillator is configured.
The piezoelectric vibrator 20 is, for example, one in which the piezoelectric vibration element X shown in FIG. 6B is housed in a ceramic package and hermetically sealed with an inert gas (N ₂ ). Is mounted via a conductive adhesive 33 on the conductor film 32 shown in FIG.
Further, a terminal electrode 21a as shown in FIG.
21b is formed.
The electronic component 26 is, for example, a chip capacitor or the like, and the wiring conductor 31 in the package 10.
, 31 are mounted via solder.

The electronic component 25 is, for example, an IC incorporating an oscillation circuit, a temperature sensor, a variable capacitance element, a temperature compensation circuit, and the like. The electronic component 25 is smaller in size than the piezoelectric vibrator 20 and is mounted on the upper surface of the piezoelectric vibrator 20 mounted in the package 10 via a conductive adhesive while avoiding the terminal electrodes 21a and 21b.
A plurality of terminal electrodes 25a, 25a... Are formed on the peripheral edge of the upper surface of the electronic component 25, and one of the terminal electrodes 25a is connected to the terminal electrode 21a by a bonding wire 34.
The other one of the terminal electrodes 25a is connected to the terminal electrode 21b by a bonding wire 34. Further, the remaining terminal electrode 25a is a stepped portion of the package 10, that is, the first frame-shaped side wall 1.
3 is connected to the pad electrode 30 formed on the upper surface 13b of the substrate 3 by a bonding wire 34.

The pad electrode 30 includes a wiring conductor 31, an internal conductor (not shown), castellations 12, 1
4, terminal electrodes VSS, VCO, CONT on the bottom surface of the package 10 shown in FIG.
, OUT, etc.
A metal (Kovar) lid 40 (not shown) is seam welded to the seal ring 18 formed on the upper surface of the package 10. At this time, the inside of the package 10 is inert gas (nitrogen gas N ₂ ) to suppress the secular change of the electronic components 25 and 26, the wiring conductor, the terminal electrode, and the like.
Is enclosed. Note that the inside of the package 10 may be in a vacuum state.
In the piezoelectric oscillator 1 configured as described above, a piezoelectric vibrator 2 in which a piezoelectric vibration element is packaged (hermetically sealed) in a space of a package 10 hermetically sealed in an inert gas atmosphere or vacuum.
By mounting 0, for example, it is configured to withstand long-term use of 10 to 20 years.

However, in the case of such a configuration, since it is necessary to mount the packaged piezoelectric vibrator 20 in the package 10 of the piezoelectric oscillator 1, the piezoelectric vibrator 20 of the piezoelectric vibrator 20 is compared with the case where only the piezoelectric vibration element is mounted. It is necessary to enlarge the internal space of the package 10 by the amount of the package, and there is a problem that the piezoelectric oscillator 1 is increased in size.
In order to increase the internal space of the package 10 without increasing the size of the piezoelectric oscillator 1, it is conceivable to reduce the thickness of the first and second frame-shaped side walls 13 and 15 constituting the package 10. However, in this case, the thickness of the castellations 14 and 16 formed on the first and second frame-like side walls 13 and 15, particularly the thickness of the second frame-like side wall 15 is reduced, and sufficient strength is obtained. There was a risk that it could not be secured.

Therefore, in the piezoelectric oscillator 1 of the present embodiment, in order to secure the internal space of the package 10 without increasing the size of the piezoelectric oscillator 1, a side view and a sectional view of FIG. ), The depth of the castellations 12 and 14 formed on the substrate 11 and the first frame-shaped side wall 13 (the radius if it is a semi-cylindrical shape), and the second frame-shaped side wall 15 The castellations 16 formed were made to have different depths. That is, in this embodiment, the depth of the castellation 16 of the second frame-shaped side wall 15 having the smallest thickness is made shallower than the castellations 12 and 14 formed on the substrate 11 and the first frame-shaped side wall 13. As a result, the internal space (internal volume) of the package 10 is increased while the second frame-shaped side wall 15 is kept thick enough. Thereby, the packaged piezoelectric vibrator 20 can be mounted inside the package 10 without increasing the size of the package 10 of the piezoelectric oscillator 1. That is, the piezoelectric oscillator 1 that is small and can maintain the electrical quality for a long time can be realized.

FIG. 3 is a cross-sectional view when forming a laminated sheet for a package of the piezoelectric oscillator of this embodiment. In this case, a green sheet provided with a plurality of holes 14 ′ having a predetermined size and an opening OP 1 on a green sheet G 1 (to be the substrate 11) having a plurality of holes 12 ′ having a predetermined size. G2 (becomes the first frame-shaped side wall 13) is stacked, and a green sheet G3 (the second frame-shaped side wall 15 and the plurality of holes 16 'having a predetermined size and an opening OP2 are further provided thereon. Become)
Are fired. At this time, the hole 12 ′ of the green sheet G1 and the hole 14 ′ of the green sheet G2 are made to penetrate through the inside with the conductive material attached to the inner wall surfaces 12a, 14a. This can be formed by sucking the conductive material in the holes 12 ′ and 14 ′ after filling the holes 12 ′ and 14 ′ of the green sheets G 1 and G 2 with the conductive material.

Next, by plating the plating solution through the holes 12 ', 14', 16 ', it is possible to plate the conductive material of the desired inner wall surfaces 12a, 14a.
Therefore, after that, if the green sheets G1, G2, and G3 laminated by BB are divided, the ceramic package 10 including the castellations 12, 14, and 16 can be obtained.
As an example, when the hole 12 ′ is cylindrical, the diameter is 0.15 mm, and the diameter of the hole 16 ′ is 0.
. It is about 08 mm to 0.1 mm.

As described above, the depth of the castellations 12, 14, 16 can be set to a desired depth by appropriately selecting the sizes of the holes 12 ', 14', 16 '.
The castellation 16 can also be plated up to a predetermined position (height). When the lid 40 is seam welded to the seal ring 18 of the package 10, the lid 40 and the castellation 16 are short-circuited. There is also an advantage that can be prevented.
Further, the shape of the holes 12 ', 14', 16 'is generally cylindrical, but may be oval, rectangular or the like.

In the present embodiment, the sizes of the holes 12 ′ and 14 ′ are the same, and the size of the hole 16 ′ is the same as the hole 12 ′.
In this case, the depth of the castellations 12 and 14 is the same, and the depth of the castellations 16 is shallower than the depth of the castellations 12 and 14. Further, when the holes 14 ′ and 16 ′ have the same size and are smaller than the hole 12 ′, the castellations 14 and 16 have the same depth and are shallower than the castellation 12.
In any case, it is important to keep the depth of the castellation 12 at the same level as the depth of the conventional package so that the bonding strength with the mounting substrate can be maintained. Further, it is important that the depth of the castellations 16 or 14 and 16 is maintained so that the strength of the package 10 can be maintained at the same level as the conventional strength.

In the present embodiment, the case where the number of green sheets is three is described as an example. However, the number of green sheets is not limited to three, and may be a number suitable for a desired package.
As described above, in this embodiment, when the green sheet is divided into the package 10, the castellation 12 on the side wall 11 c of the substrate 11 or the castellation 12 on the side wall 11 c of the substrate 11 and the first frame shape. Since the depth of the castellation 14 on the side wall 14c of the side wall 14 can be increased, the bonding strength with the mounting substrate can be maintained.
In the embodiment, since the depth of the castellation 16 on the side wall 16c of the second frame-shaped side wall 16 can be made shallower than that of the castellations 12 and 14, the piezoelectric oscillator 1 can be reduced in size while ensuring the strength of the package 10. It is possible to
In addition, by injecting an inert gas into the space of the package 10 and forming an electronic device hermetically sealed with a lid, aging of electronic components, connection conductors, electrode terminals, etc. accommodated in the multilayer ceramic package can be reduced. There is an effect that an electronic device which can be improved and can withstand use for 10 to 20 years can be configured.

FIG. 4 is a cross-sectional view showing the configuration of the piezoelectric oscillator according to the second embodiment. The difference from the piezoelectric oscillator 1 of the first embodiment shown in FIGS. The metal lid 40 is removed and the package 10 is filled with a moisture-resistant resin 45.
The amount of the resin 45 is filled up to about the upper surface 15 b of the second frame-like side wall 15 of the package 10.
Thus, by constructing an electronic device in which the space of the package 10 of the piezoelectric oscillator 2 is hermetically sealed with resin, the electronic components, connection conductors, electrode terminals, etc. accommodated in the package 10 can be prevented from vibration, impact, oxidation, etc. There is an effect that an electronic device that is protected and has a more stable quality can be configured.
In the present embodiment, a castellation 12 formed on the side surface 11c of the substrate 11,
The depth of the castellation 16 formed on the side surface 15c of the second frame-shaped side wall 15 having the smallest thickness is the same as the depth of the castellation 14 formed on the side surface 13c of the first frame-shaped side wall 13. The case where the depth is smaller than the depth of the castellation 12 (14) has been described as an example. However, this is only an example, and the side surfaces 13c and 1c of the first and second frame-like side walls 13 and 15 are provided.
The castellations 14 and 16 formed on 5c have the same depth, and the side surface 11c of the substrate 11
The depth may be shallower than the depth of the castellation 12 to be formed.
In the present embodiment, a piezoelectric oscillator has been described as an example of an electronic apparatus. However, this is merely an example, and the present invention can be applied to electronic apparatuses other than the piezoelectric oscillator.

Next, a manufacturing method of the piezoelectric oscillator according to the first embodiment will be described with reference to FIGS.
First, pad electrode 30, wiring conductor 31, conductor film 32, castellations 12, 14,
A monolithic ceramic package 10 having 16 or the like is prepared.
First, as procedure 1, solder is applied onto the capacitor wiring conductor 31 of the package 10 shown in FIG. 1 using a dispenser.
Next, as procedure 2, a capacitor (chip capacitor) 26 is mounted on the solder using a mounting device, and then this is passed through a reflow device having a predetermined temperature distribution, and the chip capacitor 26 is fixed with solder.
Next, as a procedure 3, a conductive adhesive 33 is applied to the central portion of the conductor film 32 for mounting the piezoelectric vibrator 20 using a dispenser or the like.
Next, as procedure 4, the piezoelectric vibrator 20 is mounted on the conductive adhesive 33, and the conductive adhesive is dried and cured at a predetermined temperature.
Next, as a procedure 5, a conductive adhesive is applied to the center between the end of the terminal electrodes 21a and 21b of the piezoelectric vibrator 20 and the longitudinal end of the piezoelectric vibrator 20 using a dispenser or the like. .

Next, as a procedure 6, an electronic component (IC including an oscillation circuit, a temperature compensation circuit, etc.) 25 is mounted on the conductive adhesive on the piezoelectric vibrator 20. The conductive adhesive is dried and cured at a predetermined temperature (for example, 150 ° C., 0.5 H). Note that the IC 25 does not deviate from a predetermined position of the piezoelectric vibrator 20 at this time.
Next, as procedure 7, the terminal electrodes 21 a and 21 b of the piezoelectric vibrator 20 and a predetermined terminal electrode 25 a on the IC 25 are connected by a bonding wire 34. Further, a predetermined terminal electrode 25 a on the IC 25 and a predetermined pad electrode 30 of the package 10 are bonded to the bonding wire 34.
Connect with.

Next, as procedure 8, a metal lid 40 is welded to the seal ring 18 of the package 10 using a seam welder or the like. Check for airtightness after welding.
Next, as a procedure 9, a predetermined display is engraved on the lid 40 with a laser. The piezoelectric oscillator of the present invention is completed through the above steps.
In the case of manufacturing the piezoelectric oscillator 2 according to the second embodiment shown in FIG. 4, the sealing process of the procedure 8 is changed to the process of filling the resin 45 in the process procedure shown in FIG. 4. Can only be realized.
By adopting the manufacturing method of the piezoelectric oscillator as described above, it is small in size and has an electrical quality of 10
It becomes possible to manufacture a piezoelectric oscillator that can be used for 20 to 20 years.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic which showed the structure of the piezoelectric oscillator based on this invention, (a) is a top view, (b) is sectional drawing, (c) is a composite figure of a side surface and a cross section. (A) is a side view, (b) is a bottom view. Sectional drawing of the lamination | stacking green sheet before dividing | segmenting into a package. Sectional drawing of the piezoelectric oscillator of 2nd Example. Process procedure figure. (A), (b), (c) is an exploded perspective view of the conventional piezoelectric oscillator. (A) is the perspective view which reversed the upper and lower sides of the package, (b) is a circuit diagram of a switching device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 ... Piezoelectric oscillator, 10 ... Package, 11 ... Board | substrate, 11a ... 1st main surface, 11b ... 2nd main surface, 11c ... Side surface, 12, 14, 16 ... Castellation, 12 ', 14', 1
6 '... hole, 12a, 14a, 16a ... inner wall surface, 13 ... first frame-like side wall, 13a ... upper surface,
13b ... lower surface, 13c ... side surface, 15 ... second frame-like side wall, 15c ... side surface, 18 ... seal ring, 20 ... piezoelectric vibrator, 21a, 21b ... terminal electrode, 25 ... electronic component (IC), 25a ...
Terminal electrode, 26 ... electronic component (chip capacitor), 30 ... pad electrode, 31 ... wiring conductor,
32 ... Conductive film, 33 ... Conductive adhesive, 34 ... Bonding wire, 40 ... Lid, 45 ... Resin

Claims (4)

First and second main surfaces, side surfaces continuous with the first and second main surfaces, and the first surface on the side surfaces
A substrate having a first notch that reaches the second main surface from the main surface of
A frame-like side wall disposed on the substrate and having a second cutout portion extending from the upper surface to the lower surface on a side surface continuous with the upper surface and the lower surface;
A piezoelectric vibrator housed in a space composed of the substrate and the frame-shaped side wall;
An electronic component housed in a space composed of the substrate and the frame-shaped side wall,
An electronic device, wherein a depth of at least a part of the second notch is shallower than a depth of the first notch. 2. The electronic device according to claim 1, wherein at least the first notch portion is plated out of the first notch portion and the second notch portion. The electronic device according to claim 1, wherein the space is filled with an inert gas or is in a vacuum state, and the space is sealed with a lid. The electronic device according to claim 1, wherein resin is injected into the space to seal the space.

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