JP2006033458A - Package, piezoelectric device, and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package capable of effectively preventing electronic components such as a piezoelectric vibration chip from being damaged even when a heating light beam intrudes in the package when sealing a degassing sealing hole, and to provide a piezoelectric device and a manufacturing method of the piezoelectric device. <P>SOLUTION: The piezoelectric device is configured such that the piezoelectric vibration chip 32 is contained in the package 37 and a cover 40 air-tightly seals the package, wherein the package is formed by laminating a plurality of insulation base layers, the lamination base includes: a flat lower base plate 55 for forming the bottom; and an upper base 56 laminated on the lower base plate and forming an inner space to contain the piezoelectric vibration chip by removing the interior materials, the lower base is formed with a sealing hole 61 for communicatively connecting the internal space to an external part and an edge 57 inside the upper base is located on the way of the hole diameter of the sealing hole. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a package, a piezoelectric device in which a piezoelectric vibrating piece is accommodated in the package, and a manufacturing method thereof.

Piezoelectric vibrators and oscillators in small information devices such as HDDs (hard disk drives), mobile computers, IC cards, mobile communication devices such as mobile phones, car phones, and paging systems, and gyro sensors Such piezoelectric devices are widely used.
A conventional piezoelectric device is configured, for example, as shown in a schematic sectional view of FIG. 6 (see Patent Document 1).

In the figure, the piezoelectric device 1 has an electrode portion 4 formed in a shallow box-shaped package 2 made of ceramic, and the piezoelectric vibrating piece 3 is fixed to the electrode portion 4 using a conductive adhesive 4a. The package 2 is hermetically sealed by a lid 5.
A through-hole 6 is formed in the bottom of the package 2. The through-hole 6 includes an outer first hole 6 a and a second hole 6 b communicating with the first hole 6 a. Thus, when sealing the lid 5, when the sealing material 5 a is heated in a vacuum atmosphere, for example, gas components generated from the conductive adhesive 4 a and the like are discharged from the through holes 6 to the outside of the package 2. To be discharged. By doing so, harmful gas components are prevented from adhering to the piezoelectric vibrating piece 3 and shifting the frequency.

  Here, after the degassing step using the through hole 6, a metal ball is disposed on the step portion 8 of the through hole 6, and this metal is used by using a heating light beam such as a laser beam LB. The through-hole 6 is closed with a filler 7 obtained by melting a ball so as to seal the hole.

JP 2000-106515 A

However, the through hole 6 formed in the package 2 is formed near the center of the package 2.
For this reason, when the metal ball is irradiated with the laser beam LB to form the filler 7, if the laser beam LB penetrates into the package 2 as indicated by the dotted line while melting the metal ball even for a short time, the piezoelectric material is The lower surface of the vibrating piece 3 itself is irradiated.
The laser beam LB that has entered the package 2 may partially evaporate a metal film such as an electrode of the piezoelectric vibrating piece 3. In this case, the frequency of the piezoelectric vibrating piece 3 may shift. is there.

  The present invention has been made to solve the above problems, and when sealing a degassing sealing hole, an electronic component such as a piezoelectric vibrating piece even if a heating light beam enters the package. It is an object of the present invention to provide a package, a piezoelectric device, and a method for manufacturing the piezoelectric device that can effectively prevent damage to the substrate.

According to the first aspect of the present invention, there is provided a piezoelectric device in which a piezoelectric vibrating piece is accommodated in a package and the package is hermetically sealed by a lid, wherein the package has a plurality of layers. The piezoelectric vibrating piece is formed by laminating an insulating substrate, and the laminated substrate is laminated on the flat lower substrate forming the bottom and the lower substrate, and the inner material is removed. And an upper substrate for forming an internal space for accommodating the internal space, and the lower substrate is formed with a sealing hole that communicates the internal space with the outside. This is achieved by a piezoelectric device in which the inner edge of the upper substrate is located in the middle of the hole diameter.
According to the configuration of the first aspect of the invention, when a filling metal material is disposed in the sealing hole, the edge of the upper substrate is located in the hole. The metal material is held in the package without dropping. For this reason, the metal material can be appropriately held in the sealing hole in the operation of irradiating the metal material with a heating light beam such as a laser beam to melt and fill the metal material.
In addition, when the metal material is irradiated with a light beam, the light beam is irradiated to a position near the edge of the upper substrate, so that the piezoelectric vibrating piece is irradiated even if it enters the package. There is almost no risk of damaging the electrodes of the piezoelectric vibrating piece.
Thus, according to the present invention, when sealing the degassing hole, even if the heating light beam enters the package, the piezoelectric device can be effectively prevented from damaging the electronic components such as the piezoelectric vibrating piece. Can be provided.

According to a second invention, in the configuration of the first invention, the lower substrate is formed of a single insulating substrate.
According to the configuration of the second invention, the following effects can be exhibited. That is, in the prior art, in order to make the sealing hole provided in the bottom of the package stepped, two or more substrates for constituting the bottom must be stacked, and therefore, in the thickness direction of the package. There was an inconvenience that the size was increased accordingly. On the other hand, in this invention, since the edge part of the upper board | substrate exposed inside the above-mentioned sealing hole can be utilized equivalent to the step part of the conventional stepped hole, sealing material is not melted. Therefore, it is not necessary to stack a plurality of substrates constituting the bottom portion in order to form a step portion for disposing the substrate. As a result, the lower substrate can be formed of a single insulating substrate, which is advantageous in reducing the size of the package.

According to a third invention, in the structure of the second invention, the upper substrate is formed of a single insulating substrate.
According to the configuration of the third invention, in addition to forming the lower substrate with a single insulating substrate, the size in the thickness direction of the package is minimized when the upper substrate is also formed with a single insulating substrate. be able to.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the inner periphery of the sealing hole and a step formed by a part of the upper substrate exposed in the sealing hole. A metal coating portion is provided.
According to the structure of 4th invention, the metal of the sealing material with which it fills appropriately adheres in the said sealing hole by providing the said metal coating | coated part in the inner periphery and the said step part of the said sealing hole. Is done.

According to a fifth invention, in any one of the first to fourth inventions, the sealing hole is formed adjacent to a side edge of the package.
According to the configuration of the fifth invention, in the event of sealing the hole, the sealing hole is provided adjacent to or close to the side edge that is near the one end in the width direction of the package. Even when a heating light beam enters the package, it is possible to almost certainly avoid irradiating the internal piezoelectric vibrating piece.

According to a sixth aspect of the present invention, there is provided an insulating package formed by laminating a plurality of layers of insulating substrates and having an internal space for accommodating electronic components, wherein the laminated substrate is A flat lower substrate that forms the bottom, and an upper substrate that is laminated on the lower substrate and forms an internal space for accommodating the piezoelectric vibrating piece by removing the inner material; The lower substrate is formed with a sealing hole that communicates the internal space with the outside, and the inner edge of the upper substrate is located in the middle of the hole diameter of the sealing hole. This is achieved by the structured package.
According to the configuration of the sixth invention, for the same reason as described in the invention of the first invention, after the electronic component is accommodated in the inside, when sealing the degassing hole, it is for heating. It is possible to provide a package that can effectively prevent an electronic component such as a piezoelectric vibrating piece from being damaged even if a light beam enters the package.

According to a seventh aspect of the present invention, there is provided a piezoelectric device manufacturing method in which a piezoelectric vibrating piece is accommodated in a package and hermetically sealed by a lid, wherein a plurality of insulating substrates are laminated. An individual forming step for separately forming the package to be formed, the piezoelectric vibrating piece, and the lid, and a lower substrate for forming a bottom portion of the package among a plurality of insulating substrates constituting the package In contrast, the step of bonding the piezoelectric vibrating piece, the lid sealing step of hermetically sealing the package with the lid, and heating the metal film formed on the piezoelectric vibrating piece from the outside of the package A frequency adjusting step of irradiating a light beam for use and a hole sealing step of sealing the sealing hole after degassing under heating using a sealing hole provided in the lower substrate of the package Including In the process of forming the edge, the lower substrate made of a flat insulating substrate and the upper substrate formed by removing the inner material and forming the internal space for accommodating the piezoelectric vibrating reed are respectively formed and laminated. The piezoelectric device is configured to be sintered and to form a sealing hole in the lower substrate so that the inner edge of the upper substrate is positioned in the middle of the hole diameter in the laminated state during the molding. This is achieved by the manufacturing method.
According to the structure of 7th invention, in the hole sealing process in this manufacturing method, the edge part inside the said upper board | substrate located in the middle of the said sealing hole of the said package is utilized, and it seals on it It is possible to temporarily hold a metal material for use and to melt it by applying a heating light beam thereto. In this case, since the light beam is irradiated to a position near the edge of the upper substrate, even if it enters the package, the piezoelectric vibrating piece is hardly irradiated. There is no risk of damage to the electrodes of the resonator element.
Thus, according to the present invention, when sealing the degassing hole, even if the heating light beam enters the package, the piezoelectric device can be effectively prevented from damaging the electronic components such as the piezoelectric vibrating piece. The manufacturing method of can be provided.

1 to 3 show an embodiment of a piezoelectric device of the present invention, FIG. 1 is a schematic plan view thereof, FIG. 2 is a schematic bottom view thereof, and FIG. 3 is a schematic cross-sectional view taken along line AA of FIG. is there.
In these drawings, the piezoelectric device 30 shows an example in which a piezoelectric vibrator is configured, and the piezoelectric device 30 houses a piezoelectric vibrating piece 32 in a package 37. As will be described later, the package 37 is formed by, for example, laminating a plurality of substrates formed by molding an aluminum oxide ceramic green sheet as an insulating material, followed by sintering.

That is, in this embodiment, the package 37 includes a first laminated substrate (hereinafter referred to as “substrate”) 55 as a lower substrate and a second substrate 56 as an upper substrate as shown in FIG. Is formed. In this embodiment, the bottom of the package 37 is formed by only the first substrate 55 as a single lower substrate.
As shown in FIGS. 2 and 3, the package 37 forms a space of the internal space S by removing the material inside the second substrate 56. This internal space S is a housing space for housing the piezoelectric vibrating piece 32. The piezoelectric vibrating piece 32 is bonded to the first substrate 55 which is only one substrate constituting the bottom portion.

In the inner space S of the package 37, in the vicinity of the left end portion, on the surface side of the first substrate 55 that is exposed to the inner space S and forms the inner bottom portion, for example, nickel plating and gold plating are formed on tungsten metallization. The electrode parts 31, 31 are provided.
The electrode portions 31, 31 are connected to the mounting terminals 41, 42 shown in FIG. 2 and supply a driving voltage applied from the outside to the piezoelectric vibrating piece 32. Specifically, the mounting terminals 41 and 42 and the electrode portions 31 and 31 are connected to each other by a conductive portion that is routed outside the package 37 by metallization, or tungsten metallization or the like is used before firing the first substrate 55. It can be formed by connecting with a conductive through hole or the like formed in this way.

A conductive adhesive 47 is applied on each electrode part 31, 31, and the base end part of the piezoelectric vibrating piece 32 is joined. As the conductive adhesive 47, for example, a binder component using a synthetic resin or the like is mixed with conductive particles such as silver particles, and can perform mechanical joining and electrical connection at the same time. .
In the illustrated case, the package 37 is formed in a shallow box shape having an internal space S and is hermetically sealed by a flat lid 40.
The piezoelectric vibrating piece 32 is formed of, for example, quartz, and a piezoelectric material such as lithium tantalate or lithium niobate can be used in addition to quartz. In the case of this embodiment, the piezoelectric vibrating piece 32 is, for example, an AT cut vibrating piece obtained by cutting a quartz wafer into a rectangle based on a predetermined crystal axis orientation. The piezoelectric vibrating piece is not limited to the AT-cut vibrating piece, and various piezoelectric vibrating pieces such as a tuning fork type vibrating piece and a convex type vibrating piece can be used.

  Here, at the end portions in the length direction of the piezoelectric vibrating piece 32, extraction electrodes that wrap around the front and back are formed at the corner portions at both ends in the width direction. In addition, excitation electrodes serving as driving electrodes connected to the extraction electrodes are formed on the front and back main surfaces of the piezoelectric vibrating piece 32. These electrodes are not shown. Then, as will be described later, the excitation electrode near the tip of the piezoelectric vibrating piece 32 is transmitted through a transparent lid 40 and irradiated with a heating light beam such as laser light, thereby reducing mass. The frequency can be adjusted by the method.

A lid 40 is bonded to the opened upper end of the package 37 so as to be sealed.
The lid 40 is preferably formed of a transparent material so as to enable the above-described frequency adjustment, and is formed of, for example, borosilicate glass to approximate the thermal expansion coefficient with the package 37 side. Has been.

Further, in the piezoelectric device 30 of this embodiment, a sealing hole 61 is provided at the bottom of the package 37. The sealing hole 61 is a hole for degassing the package 37 in a degassing step described later.
Specifically, as shown in FIGS. 2 and 3, the sealing hole 61 is formed by providing a through hole in the first substrate 55 that is the lower substrate. The position of the sealing hole 61 is provided adjacent to or close to the inner side edge of the first substrate 55, which is a position near one end in the width direction (X direction) of the package 37. In this case, the side edge 57 of the first substrate 55 is positioned so as to project to the middle of the hole diameter of the sealing hole 61.

As shown in the drawing, the sealing hole 61 communicates the outside of the package 37 and the internal space S. As described later, after the degassing in the package 37 in the degassing step, for example, Au Filled with a metal sealing material such as -Ge and hermetically sealed. For this reason, a part of the side edge 57 is exposed as a stepped portion 57a in the sealing hole 61 so that the metal sealing material before melting can be easily disposed. And the metal coating | coated part 63 with favorable joining property with a sealing material is formed in the inner periphery of the sealing hole 61, and the step part 57a.
The sealing hole 61 is hermetically sealed by, for example, filling a metal material such as Au—Ge as a sealing material in the hole sealing step after degassing.

The piezoelectric device 30 of the present embodiment is formed as described above. Next, an embodiment of the manufacturing method will be described.
(Piezoelectric device manufacturing method)
An embodiment of a method for manufacturing the piezoelectric device 30 will be described with reference to the flowchart of FIG.
First, the piezoelectric vibrating piece 32, the lid 40, and the package 37 described with reference to FIGS. 1 to 3 are formed separately.
(Formation process of piezoelectric vibrating piece and lid)
The piezoelectric vibrating piece 32 can be manufactured in the same manner as before by, for example, etching the quartz wafer to form the shape already described and forming the necessary excitation electrodes, and detailed description thereof is omitted. To do. If necessary, after the electrode is formed, a drive voltage is applied to roughly adjust the frequency.
The lid 40 is formed separately from the piezoelectric vibrating piece 32. In this case, the lid 40 is formed in a predetermined shape and size using a material that transmits light, for example, glass.

(Package formation process)
The first substrate 55 and the second substrate 56 of FIG. 3 are laminated after being separately molded so as to have the shape described above.
Specifically, first, for example, a ceramic powder is dispersed in a predetermined solution, and a kneaded product formed by adding a binder is formed into a sheet-like long tape shape, which is cut into a predetermined length. A so-called green sheet (not shown) is obtained.
The green sheet can be used in common to form the first and second substrates 55 and 56 described above as sheet substrates.

Next, the process of shaping | molding each board | substrate, electrode pattern printing, and the formation of the through-hole used as a sealing hole is performed.
That is, the first substrate (lower substrate) 55 cuts the above-described green sheet into a predetermined size, and forms a through hole at the above-described position determined by the relationship with the second substrate 56 to be stacked later. Thereby, the sealing hole 61 is formed.
The second substrate (upper substrate) 56 is formed by punching the inside of the green sheet into a rectangle to form a cavity that becomes the internal space S.
Subsequently, for example, tungsten metallization as a conductive paste is applied to the necessary positions of these substrates, that is, the electrode portions 31 and 31, the metal covering portion 63 of the sealing hole 61, and the predetermined routing portion as a conductive material. Part (not shown) is formed.

Next, the second substrate 56 after molding is laminated on the first substrate 55 after molding, and in this case, a binder is applied to the polymerization surface as necessary.
Next, the substrates are cut along the vertical and horizontal cutting lines of the green sheets in a stacked state, and then sintered at 1200 to 1500 degrees (Celsius). After sintering, nickel plating and gold plating are sequentially performed on the tungsten metallization to form electrodes, terminals, conductive patterns, and the like, thereby completing a package 37 as shown in FIGS. A sealing material 45 (see FIG. 3) such as low melting point glass is applied to the upper end of the package 37.
The package 37 manufactured in this way can be used not only when the piezoelectric vibrating piece is housed inside, but also as an insulating container for housing other electronic components.

(Piezoelectric vibrating piece joining process)
FIG. 5 is a process diagram briefly showing the subsequent processes.
After the formation of the package 37, as shown in FIG. 5A, the piezoelectric vibrating piece 32 is bonded onto the electrode portion 31 (see FIG. 1) of the package 37 (ST11). That is, as described with reference to FIGS. 1 and 2, the conductive adhesive 47 is applied on the electrode portion 31 of the package 37, and the portion of the extraction electrode at the base of the piezoelectric vibrating piece 32 is placed thereon, By curing the conductive adhesives 47, 47, the electrode portion 31 and the piezoelectric vibrating piece 32 are electrically and mechanically joined. In this way, the piezoelectric vibrating piece 32 is joined in a cantilever manner to the first substrate 55 that is an insulating base.

(Lid sealing process)
Further, the package 37 and the lid 40 are bonded in a vacuum atmosphere to perform lid sealing (ST12).
Here, it is important that the sealing hole 61 communicates the internal space S of the package 37 and the outside of the package 37 at this stage, and the internal space S of the package 37 is connected to the outside through the sealing hole 61. It is a point that can be ventilated.

(Degassing process)
In this state, as shown in FIG. 5B, in a predetermined jig 65, the package 37 to which the lid 40 is joined is turned upside down and held so that the stepped portion 57a faces upward. This is accommodated in a vacuum chamber (not shown) or the like, and is annealed by heating (ST13). In this process, that is, the degassing step, the gas inside the package 37 passes through the sealing hole 61 and is discharged to the outside of the package 37.

(Hole sealing process)
Next, the sealing hole 61 of FIG. 3 is sealed (ST14).
Specifically, as shown in FIG. 5C, a metal sealing material made of, for example, spherical Au—Ge or the like is formed on the stepped portion 57a of the sealing hole 61 opened to the outside of the first substrate 55. That is, a rigid metal sealing material 62 is placed, and the metal sealing material 62 is irradiated with a heating light beam LB1 such as a laser to be melted. Thus, as shown in FIG. 5D, the sealing hole 61 is filled as the sealing material 62a. In this case, since the heating light beam is highly likely to hit the side edge 57 of the second substrate 56 including the stepped portion 57a when the metal sealing material is melted and cannot be penetrated, the heating beam LB2 is not packaged. 37 does not enter the inside, and there is no possibility that the piezoelectric vibrating piece 32 is irradiated. For this reason, the frequency of the piezoelectric vibrating piece 32 is not shifted.
That is, since the stepped portion 57a can be loaded with a rigid metal sealing material 62, not only the workability is improved, but the area covered by the stepped portion 57a with respect to the hole diameter of the sealing hole 61 is made as large as possible. If only the gap necessary for the above-mentioned gas ventilation is ensured, it is possible to effectively prevent the heating light beam LB1 from entering the package 37. The heating light beam is not limited to laser light, and for example, a light beam using a halogen light can be used.

Here, when the area covered by the stepped portion 57a is set to be relatively large with respect to the hole diameter of the sealing hole 61, a heating beam LB1 such as a laser irradiated on the metal sealing material 62 correspondingly is provided in the package. It is preferable that the probability of entering the space 37 can be lowered.
However, by setting the area covered by the stepped portion 57a to be relatively small with respect to the hole diameter of the sealing hole 61, the heating beam LB1 such as a laser irradiated to the metal sealing material 62 enters the package 37. Even if it is easy, since the sealing hole 61 is formed at a position along the side edge of the second substrate 56, the intruding heating beam LB1 is irradiated to the internal piezoelectric vibrating piece 32. The risk of getting lost is very low.
In particular, in the present embodiment, the sealing hole 61 is provided at a position along the side edge of the second substrate 56 and in the vicinity of the end portion in the X direction of the package 37 as shown in FIG. Therefore, the heating beam LB1 that has passed through the sealing hole 61 and has entered the package 37 is hardly irradiated to the piezoelectric vibrating piece 32. In the hole sealing step, the electrode of the piezoelectric vibrating piece 32 and the like are used. There is no risk of damage, and the sealing hole 61 can be hermetically sealed safely and reliably.

(Frequency adjustment)
Next, as shown in FIG. 5D, a heating light beam, for example, a laser beam LB2 is applied from the outside via a transparent lid 40, or an electrode near the tip of the piezoelectric vibrating piece 32 or Irradiate the metal coating portion to adjust the frequency by the mass reduction method (ST15). Then, necessary marking is performed on the outside of the package 37 (ST16), and finally, necessary inspection is performed (ST17), and the piezoelectric device 30 is completed.

  As described above, according to this embodiment, when sealing the degassing hole, it is effective to damage electronic parts such as the piezoelectric vibrating reed even if the heating light beam enters the package. It is possible to provide a piezoelectric device and a method for manufacturing the same.

The present invention is not limited to the above-described embodiment. Each configuration of the embodiment may be omitted as appropriate and combined with other configurations not shown.
In addition, the present invention provides a piezoelectric vibrator, a piezoelectric oscillator, or the like as long as it is covered with a package or a box-shaped lid and accommodates a piezoelectric vibrating piece or a piezoelectric vibrating piece and an electronic component such as an IC. Regardless of the name, it can be applied to all piezoelectric devices and packages.

The schematic plan view which shows embodiment of the piezoelectric device of this invention. The schematic bottom view of the piezoelectric device of FIG. The AA line schematic sectional drawing of FIG. The flowchart which shows embodiment of the manufacturing method of the piezoelectric device of FIG. The schematic process drawing which concerns on embodiment of the manufacturing method of the piezoelectric device of FIG. The schematic sectional drawing which shows the conventional piezoelectric device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 30 ... Piezoelectric device, 32 ... Piezoelectric vibration piece, 31 ... Electrode part, 37 ... Package, 47 ... Conductive adhesive, 55 ... 1st board | substrate, 56 ... 2nd board | substrate, 61 ... sealing hole.

Claims (7)

A piezoelectric device that houses a piezoelectric vibrating piece in a package and hermetically seals the package with a lid,
The package is formed by laminating a plurality of insulating substrates,
In order to form an internal space for accommodating the piezoelectric vibrating reed by laminating the laminated substrate on the flat substrate forming the bottom and the material on the inner side by removing the inner material. And having an upper substrate of
The lower substrate is formed with a sealing hole that communicates the internal space with the outside,
A piezoelectric device characterized in that an inner edge of the upper substrate is located in the middle of the hole diameter of the sealing hole.   The piezoelectric device according to claim 1, wherein the lower substrate is formed of a single insulating substrate.   The piezoelectric device according to claim 2, wherein the upper substrate is formed of a single insulating substrate.   The metal covering part is provided in the inner periphery of the said sealing hole, and the step part which a part of said upper board | substrate exposed in the said sealing hole forms in any one of Claim 1 thru | or 3 characterized by the above-mentioned. The piezoelectric device described.   The piezoelectric device according to claim 1, wherein the sealing hole is formed adjacent to a side edge of the package. An insulating package formed by laminating a plurality of layers of insulating substrates and having an internal space for accommodating electronic components,
In order to form an internal space for accommodating the piezoelectric vibrating reed by laminating the laminated substrate on the flat substrate forming the bottom and the material on the inner side by removing the inner material. And having an upper substrate of
The lower substrate is formed with a sealing hole that communicates the internal space with the outside,
A package characterized in that an inner edge of the upper substrate is located in the middle of the hole diameter of the sealing hole. A method for manufacturing a piezoelectric device in which a piezoelectric vibrating piece is accommodated in a package and hermetically sealed by a lid,
A separate forming step for separately forming the package formed by laminating a plurality of insulating substrates, the piezoelectric vibrating piece, and the lid;
Bonding the piezoelectric vibrating piece to a lower substrate forming a bottom of the package among a plurality of insulating substrates constituting the package;
A lid sealing step for hermetically sealing the package with the lid;
Degassing under heating using a frequency adjustment step of irradiating a metal film formed on the piezoelectric vibrating piece from the outside of the package with a heating light beam and a sealing hole provided in the lower substrate of the package And a hole sealing step for sealing the sealing hole,
In the package forming step, the lower substrate made of a flat insulating substrate and the upper substrate formed by removing the inner material and forming the internal space for accommodating the piezoelectric vibrating reed are formed and then laminated. Made to sinter,
A sealing hole is formed in the lower substrate so that the inner edge of the upper substrate is positioned in the middle of the hole diameter in the laminated state during the molding. Production method.

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