JP2007208891A - Package for piezoelectric device and piezoelectric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining structure of a downsized piezoelectric resonator chip whereby a mount area of a piezoelectric device utilizing the piezoelectric resonator chip can furthermore be reduced, and to provide the piezoelectric device. <P>SOLUTION: In a package 20 for the piezoelectric device disclosed herein provided with an internal space S1 for housing the piezoelectric resonator chip 30, at least one side 20c of inner walls exposed in the internal space S1 has an area greater than a projected area of a principal face of the piezoelectric resonator chip 30, and an inner bottom 20a exposed in the internal space S1 is provided with joining parts 28 with which a side edge part 32a of the piezoelectric resonator chip 30 is joined. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a piezoelectric device package and a piezoelectric device.

FIG. 10 shows a conventional piezoelectric device 1 widely used in small information devices such as HDDs (hard disk drives), mobile computers, or IC cards, and mobile communication devices such as mobile phones and automobile phones. It is a schematic longitudinal cross-sectional view.
The piezoelectric device 1 in this figure is configured to accommodate a piezoelectric vibrating piece 2 in a package 3 (see, for example, Patent Document 1).

That is, the package 3 has a rectangular shape as a whole, and has an internal space S inside thereof. The bottom surface 3a exposed to the internal space S is electrically connected to the mounting terminals 4 and 4 (see FIG. Not shown). The electrodes (not shown) and the piezoelectric vibrating piece 2 are connected by conductive adhesives 5 and 5 so that the main surface of the piezoelectric vibrating piece 2 is horizontal.
However, in recent years, electronic devices described above have been remarkably miniaturized, and it is desired to reduce the mounting area of the piezoelectric device 1 used in the electronic device.

  In this regard, as shown in FIG. 11 showing another example of the conventional piezoelectric device, if the main surface of the piezoelectric vibrating piece 7 is set up along the height direction, the mounting area of the piezoelectric device 6 seems to decrease. . That is, the piezoelectric device 6 in FIG. 11 is supported by a plurality of frames 9 electrically connected to the mounting terminals 8 via lead wires so as to sandwich the main surface of the piezoelectric vibrating piece 7. (See, for example, Patent Document 2).

Japanese Patent Application Laid-Open No. 2004-343541 Japanese Patent Laid-Open No. 2004-36397

  However, due to recent technological advances, the size of piezoelectric vibrating reeds has been remarkably reduced. At present, for example, a so-called tuning fork-type piezoelectric vibrating reed having two resonating arms extending in parallel with each other from the base portion has a width. It has dimensions of 1.2 mm, length of 2 mm, and thickness of 0.6 mm, and is extremely miniaturized. For this reason, the main surface of the piezoelectric vibrating piece 7 no longer has a space necessary to be supported and fixed by being sandwiched by the frame 9 as shown in FIG. It is difficult to stand the piece 7 vertically.

  An object of the present invention is to provide a piezoelectric device package and a piezoelectric device that can further reduce the mounting area of a piezoelectric device using a miniaturized piezoelectric vibrating piece.

  According to the first aspect of the present invention, there is provided a package for a piezoelectric device provided with an internal space for accommodating a piezoelectric vibrating piece, wherein at least one surface of an inner wall exposed to the internal space is formed of the piezoelectric vibrating piece. The piezoelectric device has a larger area than the projected area of the main surface, and has an inner bottom exposed to the inner space provided with a joint for joining a side edge of the piezoelectric vibrating piece. Achieved.

According to the configuration of the first invention, at least one surface of the inner wall exposed in the internal space of the package has an area larger than the projected area of the main surface of the piezoelectric vibrating piece (that is, the piezoelectric vibrating piece has It has dimensions larger than the outer dimensions of the main surface). For this reason, the piezoelectric vibrating piece can be accommodated in the package such that the main surface thereof faces the inner wall of the package. Therefore, the inner bottom exposed in the internal space of the package is opposed to the side edge portion that is significantly smaller than the area of the main surface of the piezoelectric vibrating piece, and is formed corresponding to the side edge portion of this small area. I'll do it.
The inner bottom exposed in the internal space of the package is provided with a joint for joining the side edge of the piezoelectric vibrating piece. Therefore, even if the piezoelectric vibrating piece is downsized with no space on the main surface, the piezoelectric vibrating piece can be bonded and fixed to the package by bonding the side edge portion of the piezoelectric vibrating piece and the bonding portion of the package. .
Thus, according to the present invention, it is possible to provide a piezoelectric device package that can further reduce the mounting area of the piezoelectric device that uses the miniaturized piezoelectric vibrating piece.

According to a second invention, in the configuration of the first invention, the package is provided with a through hole that communicates the internal space with the outside and is sealed with a sealing material. It is characterized by.
According to the configuration of the second invention, the package is provided with a through hole that communicates the internal space with the outside and is sealed with a sealing material. For this reason, for example, components such as gas generated from the adhesive when the piezoelectric vibrating piece is bonded are sucked from the through hole, and then the through hole is sealed to achieve an excellent vacuum atmosphere in the package. can do. Therefore, it is possible to provide a piezoelectric device that obtains excellent vibration characteristics even with a miniaturized package that adversely affects vibration characteristics even with a minute gas component or the like.

According to a third invention, in the configuration of the first or second invention, the package includes a frame-like substrate having an opening having an area larger than the projected area of the main surface of the piezoelectric vibrating piece to be housed. The whole is formed by laminating a substantially flat substrate in the horizontal direction and in the thickness direction of the piezoelectric vibrating piece.
According to the configuration of the third invention, the package has an opening having an area larger than the projected area of the main surface of the piezoelectric vibrating piece to be accommodated (that is, an opening size larger than the outer size of the main surface of the piezoelectric vibrating piece). A frame-like substrate having an opening) and a substantially flat substrate are stacked in the horizontal direction and in the thickness direction of the piezoelectric vibrating piece. For this reason, the opening of the frame-shaped substrate becomes the opening of the package, and the piezoelectric vibrating piece is inserted into the package from this opening. The opening has an area larger than the projected area of the main surface of the piezoelectric vibrating piece. Therefore, the piezoelectric vibrating piece can be easily inserted into the package.

According to a fourth invention, in the configuration of the third invention, the opening of the frame-shaped substrate is sealed with a substrate that transmits light.
According to the structure of 4th invention, the opening part of a frame-shaped board | substrate is sealed with the board | substrate which permeate | transmits light. For this reason, even if the piezoelectric vibrating piece is erected and joined to the package, the main surface of the piezoelectric vibrating piece and the substrate that transmits light can be made to face each other. Accordingly, the frequency can be adjusted by the mass reduction method by irradiating the metal film portion of the piezoelectric vibrating piece with the laser light transmitted through the light transmitting substrate.

  According to a fifth aspect of the present invention, there is provided a piezoelectric device including a piezoelectric vibrating piece and a package provided with an internal space for accommodating the piezoelectric vibrating piece, wherein the package At least one surface of the inner wall exposed in the space has a larger area than the projected area of the main surface of the piezoelectric vibrating piece, and a side edge portion of the piezoelectric vibrating piece is formed on the inner bottom exposed in the inner space. This is achieved by a piezoelectric device provided with a joint for joining.

According to the configuration of the fifth invention, at least one surface of the inner wall exposed in the internal space of the package has an area larger than the projected area of the main surface of the piezoelectric vibrating piece (that is, the piezoelectric vibrating piece has Therefore, the inner bottom exposed in the internal space of the package is a side that is significantly smaller than the area of the main surface of the piezoelectric vibrating piece, as in the first aspect of the invention. It will be opposed to the edge, and it may be formed corresponding to the side edge of this small area.
Since the inner bottom exposed in the internal space of the package is provided with a joint for joining the side edge of the piezoelectric vibrating piece, the piezoelectric vibration can be reduced in size with no space on the main surface. Even if it is a piece, the piezoelectric vibrating piece can be bonded and fixed to the package by joining the side edge of the piezoelectric vibrating piece and the joint of the package.
Thus, according to the present invention, it is possible to provide a piezoelectric device that can further reduce the mounting area of a piezoelectric device that uses a miniaturized piezoelectric vibrating piece.

  According to a sixth aspect of the present invention, there is provided a piezoelectric device comprising a piezoelectric vibrating piece and a package provided with an internal space for accommodating the piezoelectric vibrating piece, wherein the piezoelectric vibrating piece comprises: A fixed arm joined to the package side is formed so as to extend from a region other than the excitation part having the excitation electrode, and at least one surface of the inner wall exposed to the internal space of the package has the piezoelectric vibration A joint portion for joining the fixed arm to the inner bottom exposed to the internal space and / or the surface in contact with the inner bottom is configured to have an area larger than the projected area of the main surface of the piece. This is achieved by the piezoelectric device provided.

According to the configuration of the sixth aspect of the invention, at least one surface of the inner wall exposed in the internal space of the package has an area larger than the projected area of the main surface of the piezoelectric vibrating piece (that is, the piezoelectric vibrating piece Therefore, the inner bottom exposed in the internal space of the package corresponds to the side edge portion of the piezoelectric vibrating piece having a small area, as in the first aspect of the invention. It only needs to be formed.
Then, in the case where the joint portion with the piezoelectric vibrating piece is provided on the inner bottom exposed in the internal space of the package, the side edge portion of the piezoelectric vibrating piece, the inner bottom of the package, and the like, as in the first invention Even if the piezoelectric vibrating piece is downsized and has no space on the main surface, the piezoelectric vibrating piece can be bonded and fixed to the package.
In addition, a joint may be provided on the surface contacting the inner bottom exposed in the internal space, but the portion to which the piezoelectric vibrating piece is joined is formed so as to extend from a region other than the excitation portion. It is an arm. Therefore, the piezoelectric vibrating piece can be bonded and fixed to the package even if the piezoelectric vibrating piece is reduced in size and has no space on the main surface.

In a seventh aspect based on the sixth aspect, the joint projects from the inner bottom exposed to the inner space and / or from the surface in contact with the inner bottom so as to sandwich the fixed arm. It is characterized by.
According to the structure of 7th invention, the junction part protrudes so that a fixed arm may be pinched | interposed from the inner bottom exposed to internal space, and / or the surface which contact | connects this inner bottom. Therefore, when mounting the piezoelectric vibrating piece on the package, it is effective that the protruding portion of the joint restricts the movement of the piezoelectric vibrating piece and the piezoelectric vibrating piece falls down before the adhesive is cured. Can be prevented.

1 to 4 show a piezoelectric device 10 according to a first embodiment of the present invention, and FIG. 1 is a schematic plan view of the piezoelectric device 10 (that is, when the piezoelectric device 10 is connected to a mounting substrate, FIG. 2 is a schematic cross-sectional view taken along line AA of FIG. 1, FIG. 3 is a schematic view of the main surface of the piezoelectric vibrator 30 used in the piezoelectric device 10, and FIG. -B line end view.
For convenience of understanding, FIG. 1 shows a lid that will be described later through. Further, the portions indicated by the parallel oblique lines in FIGS. 1 to 3 are shown for convenience of understanding, and do not represent a cross section or the like.
In addition, the term “piezoelectric device” as used herein means all products in which a piezoelectric vibrating piece is accommodated in a package, regardless of the names of a piezoelectric vibrator, a piezoelectric oscillator, a piezoelectric gyro sensor, and the like.

The piezoelectric device 10 in these drawings shows an example in which a surface-mount type piezoelectric vibrator is configured. The piezoelectric device 10 houses a piezoelectric vibrating piece 30 in a package 20.
The piezoelectric vibrating piece 30 is formed of, for example, quartz or the like, and a piezoelectric material such as lithium tantalate or lithium niobate can be used in addition to the quartz.

  The piezoelectric vibrating reed 30 is formed with substantially the same thickness D1 except for a long groove 50 described later. As shown in FIG. 2 and FIG. 44 and 45 are provided to form the excitation portion 30a, and extraction electrodes 46 and 47 are provided so as to draw out the excitation electrodes 44 and 45 to form the extraction portion 30b.

Since the piezoelectric vibrating piece 30 of the present embodiment is erected and joined to the package 20 as described later, the following configuration is employed to reduce the size (in the present embodiment, 2 mm × 1.2 mm × 0. It is designed to be 6 mm), preventing overturning.
First, the piezoelectric vibrating piece 30 is a so-called tuning fork type piezoelectric vibrating piece. In other words, the pair of vibrating arms 34 and 35 extending in parallel with each other of the piezoelectric vibrating piece 30 serves as the excitation unit 30a, and the base portion that supports the pair of vibrating arms 34 and 35 serves as the extraction unit 30b.

  In addition, as shown in FIGS. 3 and 4, the vibrating arms 34 and 35 separated into two forks from the lead-out portion 30 b are formed with long grooves 50 extending along the longitudinal direction on the front and back surfaces, respectively. It is almost H-shaped. An excitation electrode 44 is formed in the long groove 50 of the vibrating arm 35, and an excitation electrode 45 is formed on the side surface of the vibrating arm 35 so as to face the excitation electrode 44 in the long groove 50. An excitation electrode 45 is formed in the long groove 50 of the vibrating arm 34, and the excitation electrode 44 is formed on the side surface of the vibrating arm 34 so as to face the excitation electrode 45 in the long groove 50. The excitation electrodes 44 and 45 are electrically connected to a pair of extraction electrodes 46 and 47 drawn to the base and have different polarities.

As a result, the electric field efficiency can be increased in the vibrating arms 34 and 35 and the crystal impedance value (CI value) can be lowered, so that the piezoelectric vibrating piece 30 can be reduced in size.
Further, although not shown in the drawing, the lead-out portion 30b that is a base portion that supports the pair of vibrating arms 34 and 35 is formed with a notch portion (not shown) facing the side surface so as to reduce the width direction. Of course, so-called vibration leakage is prevented and the piezoelectric vibrating piece 30 can be downsized.

As shown in FIG. 1 and FIG. 2, the package 20 has an inner bottom 20 a that is surrounded by inner walls and to which the piezoelectric vibrating piece 30 is bonded.
Specifically, the package 20 is formed by, for example, laminating a first substrate 21 and a second substrate 22 formed by molding an aluminum oxide ceramic green sheet as an insulating material, and then sintering. Has been.

The first substrate 21 is formed with a predetermined hole inside thereof, so that when the first substrate 21 is stacked on the second substrate 22, a predetermined internal space S <b> 1 is formed inside the package 20.
This internal space S1 is a cavity for accommodating the piezoelectric vibrating piece 30 and is formed in a rectangular shape in this embodiment.
Further, the opening end surface 21a on the opening 20b side that opens upward in FIG. 2 of the first substrate 21 is made of, for example, a metal such as Kovar (Fe-Ni-Co) using a Koval seam ring 24 or the like. The lid body 26 formed of the alloy is joined, and the internal space S1 is sealed with the lid. Thus, the lid 26 is made of metal, so that it can be grounded and have a shielding effect.

The entire second substrate 22 has a flat plate shape, and mounting terminals 23 are provided on both ends of the bottom surface in the longitudinal direction.
In addition, a pair of mount electrodes 28 and 28 formed by nickel plating and gold plating on, for example, tungsten metallization are provided on the bottom surface exposed to the internal space S1 of the second substrate 22, that is, the inner bottom 20a of the package 36. Yes.
The mount electrodes 28, 28 provided on the package 20 serve as a joint for joining the piezoelectric vibrating piece 30.

As shown in FIG. 2, each of the mount electrodes 28, 28 is connected to the mounting terminal portions 23, 23 on the back surface via conductive patterns 29, 29 in via holes provided in the second substrate 22. Thus, the electrodes have different polarities and serve as electrodes for supplying a driving voltage to the piezoelectric vibrating piece 30.
Specifically, the mount electrodes 28 and 28 are provided at positions facing connection electrodes 48 and 49 of the piezoelectric vibrating piece 30 described later. Then, a conductive adhesive such as silicone, epoxy, or polyimide is applied as an adhesive 40, 40 on the mount electrodes 28, 28, and the piezoelectric vibrating piece 30 is mounted on the adhesive 40, 40. As a result, the mounting electrodes 28 and 28 and the piezoelectric vibrating piece 30 are electrically and mechanically connected. In addition, it is preferable to use the flexible silicone type conductive adhesive which can absorb the impact from the outside as the adhesives 40 and 40.

Here, the package 20 and the piezoelectric vibrating piece 30 of the present embodiment have the following characteristic structures.
First, as shown in FIG. 2, for the package 20, at least one surface 20 c of the inner wall (inner side surface) exposed in the internal space S <b> 1 has an area larger than the projected area of the main surface of the piezoelectric vibrating piece 30. It has become. In addition, since the internal space S <b> 1 of the present embodiment is formed in a substantially rectangular shape, two opposing surfaces of the inner wall have an area larger than the projected area of the main surface of the piezoelectric vibrating piece 30.

  In other words, the inner wall surface 20c exposed in the internal space S1 and the main surface of the piezoelectric vibrating piece 30 face each other so that the piezoelectric vibrating piece 30 can be accommodated. Have. Specifically, as shown in FIG. 1 and FIG. 2, the longest side of the main surface of the piezoelectric vibrating piece 30 is the length L1, and the vertical direction of the main surface with respect to the length L1 is the width W1. When the thickness is D1, the height H2 of the internal space S1 of the package 20 corresponds to the width W1 of the piezoelectric vibrating piece 30, the length L2 of the internal space S1 corresponds to the length L1 of the piezoelectric vibrating piece 30, A depth D2 of the space S1 is formed corresponding to the thickness D1 of the piezoelectric vibrating piece 30.

The inner bottom 20a exposed in the internal space S1 is provided with joint portions (hereinafter referred to as “mount electrodes”) 28 and 28 for joining the side edge portion 32a of the piezoelectric vibrating piece 30.
Preferably, the mount electrodes 28, 28 provided at two locations along the longitudinal direction of the package 30 are arranged on both sides of the width direction virtual line CL1 passing through the center of gravity OP of the piezoelectric vibrating piece 30. Yes. As a result, when the piezoelectric vibrating piece 30 is mounted, the piezoelectric vibrating piece 30 can be effectively prevented from falling or tilting.

  Next, as for the piezoelectric vibrating piece 30, as shown in FIGS. 2 and 4, the side edge portion 32 a other than the excitation portion 30 a is directly joined to the inner bottom 20 a of the package 20. That is, as described above, the inner wall 20c exposed in the internal space S1 of the package 20 is made larger than the projected area of the main surface of the piezoelectric vibrating piece 30, so that the main surface of the piezoelectric vibrating piece 30 is the inner wall 20c. It can now be accommodated in the package 20 so as to face the surface. For this reason, the side edge portion 32 a of the piezoelectric vibrating piece 30 is joined to the inner bottom 20 a of the package 20.

In the case of the present embodiment, the piezoelectric vibrating piece 30 is formed with a fixed arm 32 joined to the package 20 side so as to extend the lead-out portion 30 b, and the side edge portion 32 a of the fixed arm 32 is connected to the package 20. It is joined to the inner bottom 20a.
In other words, the fixed arm 32 is formed integrally with the lead-out portion 30 b and is a member formed to join the piezoelectric vibrating piece 30 to the package 20, and an adhesive that can maintain the posture of the piezoelectric vibrating piece 30. It has a length that can be applied.

Specifically, the fixed arm 32 is positioned at the end 30c farthest from the excitation portion 30a of the extraction portion 30b (in the present embodiment, near the corner portion at the end opposite to the excitation portion 30a of the extraction portion 30b). Is formed along the longitudinal direction of the piezoelectric vibrating piece 30 so as to face the side edge of the excitation unit 30a.
In this way, the piezoelectric vibrating piece 30 makes it difficult to transmit the vibration of the excitation unit 30a to the package 20 by joining the fixed arm 32 away from the excitation unit 30a actively participating in the vibration to the package 20. It is possible to make it difficult for vibration on the package 20 side and stress of the conductive adhesive 40 to be transmitted to the excitation unit 30a.

The fixed arm 32 is provided with a pair of connection electrodes 48 and 49 that are electrically connected to the mount electrodes 28 and 28 on the package 20 side so that the extraction electrodes 46 and 47 extend. A portion of the pair of connection electrodes 48 and 49 drawn around the side edge portion 32a outside the fixed arm 32 is connected to the mount electrodes 28 and 28 on the package 20 side.
For the fixed arm 32, a groove 52 is formed between the pair of polarized electrodes 48, 49 of the connection electrodes 48, 49, and the conductive adhesive 48 attached to the connection electrode 48 and the connection electrode 49. 48 should be prevented from contacting each other.

  The pair of polarized electrodes of the extraction electrodes 46 and 47 and the connection electrodes 48 and 49 have substantially the same area. That is, among the electrodes having different polarities, the extraction electrode 46, the connection electrode 48 formed integrally with the extraction electrode 46, the extraction electrode 47 and the connection electrode 49 formed integrally with the extraction electrode 47, Are provided on the surface of the piezoelectric body with substantially the same area. Thereby, the mutual electric capacity is made the same, and the voltage is supplied to the excitation unit 30a in a balanced manner.

The first embodiment of the present invention is configured as described above. Since one surface 20c of the inner wall (inner side surface) of the package 20 has an area larger than the projected area of the main surface of the piezoelectric vibrating piece 30, the piezoelectric The resonator element 30 can be accommodated in the package 20 such that the main surface thereof stands up to face one surface 20c of the inner wall. Therefore, the inner bottom 20a of the package 20 is opposed to the side edge 32a that is significantly smaller than the area of the main surface of the piezoelectric vibrating piece 30, and is formed corresponding to the side edge 32a having this smaller area. As a result, the mounting area can be greatly reduced.
Further, a joint portion (mount electrode) 28 for joining the side edge portion 32 a of the piezoelectric vibrating piece 30 is provided on the inner bottom 20 a of the package 20. Therefore, even if the piezoelectric vibrating piece 30 is reduced in size with no space on the main surface, the side edge portion 32a of the piezoelectric vibrating piece 30 and the bonding portion (mount electrode) 28 of the package 20 are bonded, The piezoelectric vibrating piece 30 can be bonded and fixed to the package 20.

In this embodiment, as shown in FIG. 2, the adhesive 40 is also attached to the main surface of the piezoelectric vibrating piece 30, but the portions to which the adhesive 40 is attached are the excitation part 30 a and the extraction part 30 b. Since this is the main surface of the fixed arm 32 provided separately, the influence on the vibration characteristics of the piezoelectric vibrating piece 30 is small and there is no problem.
Further, as described above, a so-called tuning fork type piezoelectric vibrating piece is used for the piezoelectric vibrating piece 30 of the present embodiment, but the present invention is not limited to such a piezoelectric vibrating piece. It may be a so-called AT-cut resonator element, or a SAW resonator or the like.

FIG. 5 is a schematic longitudinal sectional view corresponding to FIG. 2, which is a modification of the first embodiment of the present invention. In addition, the part of the parallel oblique line of this figure is shown for the convenience of understanding, Comprising: A cross section etc. are not represented.
In this figure, the portions denoted by the same reference numerals as those used in the description of FIGS. 1 to 4 have the same configuration, and therefore, a duplicate description will be omitted, and hereinafter, differences will be mainly described.

The piezoelectric device 12 is different from the piezoelectric device 10 of FIGS. 1 to 5 only in the through hole provided in the package 20.
That is, the package 20 is provided with a through hole 51 that communicates the internal space S1 with the outside and is sealed with the sealing material 50.

  Specifically, the substrate 22 constituting the bottom of the package 20 is formed by laminating two substrates 22a and 22b, and through holes 51a and 51b are formed in the substrates 22a and 22b, respectively. Thus, a through hole 51 opened to the outside is provided. Of the two through holes 51a and 51b, the through hole 51a, which is an outer hole, has a larger inner diameter than the through hole 51b opened in the internal space S1 of the package 20. Thus, the through hole 51 is a stepped opening including a downward stepped portion 52, and a metal film is formed on the surface of the stepped portion 52.

  As the sealing material 50, a solder ball or the like can be used. That is, the package 20 is arranged so that the mounting terminal portion 23 faces upward, the solder ball is placed on the stepped portion 52 described above, and the solder ball is melted by irradiating a laser with the solder ball. The through hole 51 is sealed by wetting and spreading the film.

  The modification of the first embodiment of the present invention is configured as described above, and the package 20 communicates with the internal space S1 and the outside and is sealed with a sealing material 50. A through-hole 51 is provided. Therefore, in the manufacturing process, the gas generated by heating the conductive adhesive 40, the brazing material 24, and the like is exhausted from the through hole 50 to prevent the gas from adhering to the piezoelectric vibrating piece 30 and The vibration frequency of the vibration piece 30 is prevented from changing. In particular, when the piezoelectric device 12 is formed in a small size, the adhesion of the gas has a great effect on the vibration characteristics.

6 and 7 show a piezoelectric device 14 according to a further modification of the modification of the first embodiment of the present invention. FIG. 6 is a schematic longitudinal sectional view corresponding to FIG. 2, and FIG. It is a schematic sectional drawing at the time of cut | disconnecting in the position of CC line. 6 are shown for convenience of understanding, and do not represent a cross section or the like.
In this figure, the portions denoted by the same reference numerals as those used in the description of FIGS. 1 to 5 have a common configuration, and therefore, a duplicate description will be omitted, and hereinafter, differences will be mainly described.

The piezoelectric device 14 differs from the piezoelectric devices 10 and 12 of FIGS. 1 to 5 only in the joint portion of the package 20 with the piezoelectric vibrating piece 30.
That is, the joint portions 28 and 56 protrude so as to sandwich the fixed arm 32 from the inner bottom 20a exposed to the inner space S1 and / or the surface 20c in contact with the inner bottom 20a.
1 to 5 is only the portion where the mount electrode 28 is provided, but in the present embodiment, the portion 56 where the mount electrode 28 is not provided is also the piezoelectric vibrating piece 30. Are joined to form a joint.

Specifically, the first substrate 21 for forming the internal space S1 is formed by laminating a plurality of substrates 21a and 21b, and the main surface of the fixed arm 32 of the substrate 21b in contact with the inner bottom 20a and The opposed inner walls 56 a are close to the main surface of the fixed arm 32.
Then, a conductive adhesive 40 is applied on the mount electrode 28, and the side edge 32a of the fixed arm 32 is placed thereon, so that the side edge 32a and the side edge 32a of the fixed arm 32 are placed. A conductive adhesive 40 is attached to the main surface in contact therewith.

The piezoelectric device 14 according to a further modification of the above-described first modification of the present invention is configured as described above, and the joint portions 28 and 56 include the inner bottom 20a exposed to the inner space S1 and / or the inner bottom 20a. It protrudes so that the fixed arm 32 may be pinched | interposed from the surface 20c which touches the inner bottom 20a. Therefore, when the piezoelectric vibrating piece 30 is mounted on the package 20, the inner wall 56 a facing the main surface of the fixed arm 32 of the joint portion 56 restricts the movement of the piezoelectric vibrating piece 30, and the conductive adhesive 40 is cured. It is possible to effectively prevent the piezoelectric vibrating piece 30 from tipping over before.
Since the joining portion 56 is sandwiched between the main surfaces of the fixed arm 32 provided separately from the excitation portion 30a and the extraction portion 30b, the influence on the vibration characteristics of the piezoelectric vibrating piece 30 is small.
Note that the mount electrode 28 may also be provided on the inner wall 56 a facing the main surface of the fixed arm 32.

8 and 9 show a piezoelectric device 16 according to the second embodiment of the present invention, in which FIG. 8 is a schematic longitudinal sectional view corresponding to FIG. 2, and FIG. 9 is a position along line DD in FIG. It is a schematic sectional drawing at the time of cut | disconnecting. In addition, the part of the parallel oblique line of FIG. 8 is shown for convenience of understanding, and does not represent a cross section or the like.
In this figure, the portions denoted by the same reference numerals as those used in the description of FIGS. 1 to 7 have a common configuration, and therefore, a duplicate description will be omitted, and hereinafter, differences will be mainly described.

The piezoelectric device 16 is mainly different from the piezoelectric devices 10, 12, and 14 of FIGS. 1 to 7 in the stacked structure of the package 20 and the lid.
That is, the package 20 of the piezoelectric device 16 includes a frame-shaped substrate 62, 63 having an opening 63a having an area larger than the projected area of the main surface of the piezoelectric vibrating piece 30 to be accommodated, and a substantially flat substrate. 60 and 61 are stacked in the horizontal direction in the thickness D1 direction of the piezoelectric vibrating piece 30 (the left-right direction in FIG. 9).

  And after accommodating in the inside of this frame-shaped board | substrate 62,63 so that the main surface of the piezoelectric vibrating piece 30 may oppose the inner wall 20c exposed to internal space S1, the opening part of this frame-shaped board | substrate 62,63 63a (which becomes the opening of the package 20) is sealed (sealed in the internal space S1) with a substrate 68 that transmits light, such as glass, using a brazing material 66 such as low-melting glass. For this reason, the substrate 62 that transmits light is disposed on the side surface of the package 20 that faces the main surface of the piezoelectric vibrating piece 30.

More specifically, the frame-shaped substrate 63 and the substantially flat substrate 61 are stacked in a horizontal direction via another frame-shaped substrate 62. Through holes 62a and 63a are formed in the frame-like substrates 62 and 63, respectively, and the internal space S1 is formed by overlapping the through holes 62a and 63a.
Further, the through hole 63a provided in the substrate 63 on the side of the substrate 68 that transmits light is formed larger than the through hole 62a provided in the substrate 62 on the side opposite to the substrate 68 that transmits light. Then, by laminating the two frame-shaped substrates 62 and 63, the substrate 62 on the side opposite to the substrate 68 that transmits light is exposed to the internal space S1 and faces the main surface of the fixed arm 32. An inner wall 62b is formed.
The region of the inner wall 62b becomes a joint portion. That is, the mount electrode 28 is disposed on the inner wall 62 b and the fixing arm 32 is joined with the conductive adhesive 40.

Further, as shown in FIG. 9, the package 20 is also disposed on the lower side (mounting terminal 23 side) of the substrate 68 that transmits light. Specifically, the frame-like substrate 63 on the substrate 68 side that transmits light forms an upward stepped portion 63b on the end surface of the opening on the mounting terminal 23 side. A material 66 is applied to join the lower end surface 68a (mounting terminal 23 side) of the substrate 68 that transmits light.
Accordingly, the mounting terminal 23 is also formed at the bottom of the package 20 disposed on the lower side of the substrate 68 that transmits light, and the space below the substrate 68 that transmits light is effectively utilized. Mounting strength can be increased. In addition, the package 20 disposed below the light-transmitting substrate 68 can protect the end surface 68a of the substrate 68 that transmits light such as glass that is easily chipped.

  The second embodiment of the present invention is configured as described above, and the package 20 has a frame-like substrate having an opening 63a having an area larger than the projected area of the main surface of the piezoelectric vibrating piece 30 to be accommodated. The main surface 63 and the main surface of the substantially flat substrate 61 are laminated in the horizontal direction in the thickness D1 direction of the piezoelectric vibrating piece 30. Therefore, the opening 63a of the frame-shaped substrate 63 becomes the opening of the package 20, and the opening 63a has an area larger than the projected area of the main surface of the piezoelectric vibrating piece 30, so that the piezoelectric vibrating piece 30 can be easily formed. Can be inserted into the package 20.

  Further, the opening 63a of the frame-shaped substrate 63 is open in the horizontal direction and in the direction of the thickness D1 of the piezoelectric vibrating piece 30, and the opening 63a is sealed with a substrate 68 that transmits light. Therefore, even if the piezoelectric vibrating piece 30 is erected and joined to the package 20, the main surface of the piezoelectric vibrating piece 30 can be opposed to the substrate 68 that transmits light. Therefore, as shown in FIG. 9, the laser beam LB is transmitted through the substrate 68 that transmits light, and is irradiated onto the metal film portion of the piezoelectric vibrating piece 30, and the frequency can be adjusted by a mass reduction method.

  The present invention is not limited to the above-described embodiment. Each configuration of the embodiment and each modified example can be appropriately combined or omitted, and can be combined with other configurations not shown.

1 is a schematic plan view of a piezoelectric device according to a first embodiment of the present invention. FIG. 2 is a schematic sectional view taken along line AA in FIG. 1. 1 is a schematic view of a main surface of a piezoelectric vibrator used in a piezoelectric device according to a first embodiment of the present invention. FIG. 4 is an end view taken along line BB in FIG. 3. It is a modification of the 1st Embodiment of this invention, Comprising: The schematic longitudinal cross-sectional view corresponding to FIG. FIG. 5 is a schematic longitudinal sectional view corresponding to FIG. 2, illustrating a piezoelectric device according to a further modification of the modification of the first embodiment of the present invention. The schematic sectional drawing at the time of cut | disconnecting in the position of CC line of FIG. It is a piezoelectric device which concerns on the 2nd Embodiment of this invention, Comprising: The schematic longitudinal cross-sectional view corresponding to FIG. FIG. 9 is a schematic cross-sectional view taken along the line DD in FIG. 8. The schematic longitudinal cross-sectional view of the conventional piezoelectric device. The longitudinal cross-sectional view which showed the other example of the conventional piezoelectric device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10, 12, 14, 16 ... Piezoelectric device, 20 ... Package, 20a ... Inner bottom, 20c ... One surface of inner wall, 30 ... Piezoelectric vibrating piece, 30a ... Excitation part, 30b ... Extraction part, 32 ... Fixed arm, 32a ... Side edge, 44,45 ... Excitation electrode, 46,47 ... Extraction electrode

Claims (7)

A package for a piezoelectric device provided with an internal space for accommodating a piezoelectric vibrating piece,
At least one surface of the inner wall exposed in the internal space has a larger area than the projected area of the main surface of the piezoelectric vibrating piece,
A package for a piezoelectric device, characterized in that a bonding portion for bonding a side edge portion of the piezoelectric vibrating piece is provided on the inner bottom exposed in the internal space. 2. The piezoelectric device according to claim 1, wherein the package is provided with a through hole that communicates the internal space with the outside and is sealed with a sealing material. package.   The package includes a frame-like substrate having an opening having an area larger than a projected area of a main surface of a piezoelectric vibrating piece to be accommodated, and a substrate having a substantially flat plate as a whole in a horizontal direction. The piezoelectric device package according to claim 1, wherein the piezoelectric device package is formed by laminating in a thickness direction.   4. The package for a piezoelectric device according to claim 3, wherein the opening of the frame-shaped substrate is sealed with a substrate that transmits light. A piezoelectric device comprising a piezoelectric vibrating piece and a package provided with an internal space for accommodating the piezoelectric vibrating piece,
The package is
At least one surface of the inner wall exposed in the internal space has a larger area than the projected area of the main surface of the piezoelectric vibrating piece,
A piezoelectric device characterized in that a bonding portion for bonding a side edge portion of the piezoelectric vibrating piece is provided on the inner bottom exposed in the internal space. A piezoelectric device comprising a piezoelectric vibrating piece and a package provided with an internal space for accommodating the piezoelectric vibrating piece,
The piezoelectric vibrating piece is
A fixed arm joined to the package side is formed so as to extend from a region other than the excitation part having the excitation electrode,
The package is
At least one surface of the inner wall exposed in the internal space has a larger area than the projected area of the main surface of the piezoelectric vibrating piece,
A piezoelectric device comprising: a joint portion for joining the fixed arm to an inner bottom exposed to the inner space and / or a surface in contact with the inner bottom.   The piezoelectric device according to claim 6, wherein the joint portion protrudes from the inner bottom exposed in the internal space and / or a surface in contact with the inner bottom so as to sandwich the fixed arm.

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