JP4830071B2 - Piezoelectric vibration device and method of manufacturing the same - Google Patents

Description

  The present invention relates to a piezoelectric vibration device and a method for manufacturing the piezoelectric vibration device.

Conventionally, in a piezoelectric vibration device, there is no deterioration in vibration characteristics due to a change in mounting state of the piezoelectric body,
As a fixed connection electrode structure having excellent impact resistance, a structure is known in which the cross section of the fixed connection electrode has a concave shape, a conductive fixing member is applied to the concave portion, and the piezoelectric body is fixedly connected to the fixed connection electrode (for example, Patent Document 1).

JP 2002-26681 A

However, in recent years, the piezoelectric body (hereinafter referred to as a piezoelectric vibrating piece) has become thinner than before as the frequency of the piezoelectric vibration device has increased and the package has become smaller and thinner.
For this reason, the piezoelectric vibrating piece is likely to be deformed by contraction at the time of fixing a conductive fixing member (hereinafter referred to as a fixing agent) that fixes the piezoelectric vibrating piece to a fixed connection electrode (hereinafter referred to as an internal electrode).

Here, FIG. 11 schematically shows a result of investigation by the inventors of the present invention on a deformation state after the piezoelectric vibrating piece is fixed in the conventional structure.
11A is a schematic plan view of the piezoelectric vibration device 101, FIG. 11B, FIG. 11C, and FIG.
), (E) shows the JJ line, KK line, LL line, and MM line in FIG.
It is sectional drawing in a line. Note that the lid, the bonding material, and the like of the piezoelectric vibration device 101 are omitted. In addition, the deformed shape of the piezoelectric vibrating piece 103 is exaggerated for easy understanding.

The fixing agent 105 is applied to the recesses 104c and 104d of the internal electrodes 104a and 104b having a concave cross section formed on the inner surface of the package 102, and the piezoelectric vibrating piece 103 is attached to the internal electrode 104a and
It adheres to 104b. Note that the fixing agent 105 has a property of shrinking upon curing, and the amount of shrinkage increases as the thickness increases.
When the fixing agent is cured, the portions of the piezoelectric vibrating piece 103 located on the recesses 104c and 104d are contracted by the fixing agent 105, so that the recesses 104c and 104c are formed as shown in FIGS.
It may be deformed to be pulled into 104d.

At the same time, with the edges of the recesses 104c and 104d as fulcrums, the portions of the piezoelectric vibrating piece 103 located around the internal electrodes 104a and 104b may be deformed to warp. Then, as shown in FIGS. 11 (d) and 11 (e), this deformation causes the vibrating portion 1 of the piezoelectric vibrating piece 103.
May extend to 03a.

That is, in the conventional example described in Patent Document 1, the concave portions 10 of the internal electrodes 104a and 104b are provided.
Due to the shrinkage of the fixing agent 105 applied to 4c and 104d, the vibrating portion 10 of the piezoelectric vibrating piece 103
There is an unsolved problem that 3a may be deformed.
The present invention has been made paying attention to this unsolved problem, and an object of the present invention is to provide a piezoelectric vibration device and a method of manufacturing the piezoelectric vibration device that can reduce the deformation of the vibration part of the piezoelectric vibration piece. To do.

In order to solve the above-described problem, a piezoelectric vibration device according to a first aspect of the present invention is a substrate, two protrusions formed to protrude from one surface of the substrate, and the two protrusions. A piezoelectric vibrating piece having a gap between one surface and a fixing agent for fixing the piezoelectric vibrating piece to each of the two protrusions, wherein the piezoelectric vibrating piece connects the protrusions to each other. In one direction, a vibration part that extends outward from each of the two protrusions and generates a piezoelectric vibration of the piezoelectric vibrating piece intersects the first direction when viewed in a plan view. In two directions, it is formed so as to extend away from the two protrusions starting from positions outside the two protrusions, and the fixing agent, the substrate, and the two protrusions. And cut the piezoelectric vibrating piece along the first direction. When the cross section is viewed, the sticking agent exceeds the other edge at the position of the two protrusions, starting from the range from one edge on the side between the protrusions to the other edge, It extends outside the range, and is sandwiched between the substrate and the piezoelectric vibrating piece outside the range.

According to the first invention, in the first direction, the thickness of the sticking agent is thicker outside this range than the range from the starting point of the sticking agent to the other edge. And as the thickness of the fixing agent increases, the amount of shrinkage during curing increases. Accordingly, the piezoelectric vibrating piece is subjected to a force that is pulled away from the protrusions due to the difference in contraction amount between the range from the starting point of the fixing agent to the other edge and the outside of this range.

As a result, the portion spanned between the protrusions of the piezoelectric vibrating piece and the vibration part formed so as to extend outward from the protrusion in the second direction are not easily deformed due to a flat tension. . Thereby, the deformation | transformation in the 1st direction of the vibration part of a piezoelectric vibrating piece can be reduced.

According to a second aspect of the present invention, in the piezoelectric vibration device according to the first aspect, the piezoelectric vibrating piece extends outward from each of the two protrusions in a direction away from the vibration portion with the two protrusions interposed therebetween. When the cross-section of the fixing agent, the substrate, the two protrusions, and the piezoelectric vibrating piece cut along the second direction is viewed, the fixing agent is positioned at the two protrusions. In the range from one edge of the projecting portion to the other edge on the opposite side of the one edge, over the other edge and from the one edge to the other edge. It extends outside the range to the other edge, and is sandwiched between the substrate and the piezoelectric vibrating piece outside the range.

According to the second invention, in the second direction, the thickness of the sticking agent is thicker outside this range than the range from the starting point of the sticking agent to the other edge. And as the thickness of the fixing agent increases, the amount of shrinkage during curing increases. Therefore, the piezoelectric vibrating piece is subjected to a force that is sandwiched between the protruding portion and the other side of the vibrating portion due to a difference in contraction amount between the range from the starting point to the other edge and outside this range.

As a result, the vibrating portion of the piezoelectric vibrating piece can easily secure a gap with the substrate. Thereby, the deformation | transformation in the 2nd direction of the vibration part of a piezoelectric vibrating piece can be reduced.

According to a third aspect of the present invention, there is provided a piezoelectric vibration device including a substrate, two protrusions formed so as to protrude from one surface of the substrate, and spanned between the two protrusions, between the one surface. A piezoelectric vibrating piece having a gap, and a fixing agent for fixing the piezoelectric vibrating piece to each of the two protrusions, each of the two protrusions being moved from the inside of the protrusion toward the outer periphery, The piezoelectric vibrating piece is formed in a first direction that connects the maximum protrusions with the largest thickness of each of the two protrusions in the first direction. The vibration part that extends outward from the maximum projecting part and generates the piezoelectric vibration of the piezoelectric vibrating piece in a second direction that intersects the first direction when viewed in a plan view, Starting from the position outside each of the two protrusions, The cross section is formed so as to extend away from the two protrusions, and the adhesive, the substrate, the two protrusions, and the piezoelectric vibrating piece are cut along the first direction. When the sticking agent is at the position of the two protrusions,
From the first edge on the side between the protrusions to the second edge opposite to the first edge, starting from the range from the maximum protrusion to the second edge, the second edge And is sandwiched between the protrusion and the piezoelectric vibrating piece.

According to the third invention, in the first direction, the thickness of the sticking agent of the protrusion is made thicker in the vicinity of the second edge than in the vicinity of the starting point of the sticking agent. And as the thickness of the fixing agent increases, the amount of shrinkage during curing increases. Therefore, a force that is pulled toward the direction away from the protrusions acts on the piezoelectric vibrating piece due to the difference in shrinkage between the vicinity of the starting point of the fixing agent and the vicinity of the second edge.

As a result, a flat tension is applied to the portion spanned between the protrusions of the piezoelectric vibrating piece and the vibrating portion of the piezoelectric vibrating piece formed to extend outward from the protrusion in the second direction. Therefore, it is difficult to deform. Thereby, the deformation | transformation in the 1st direction of the vibration part of a piezoelectric vibrating piece can be reduced.

According to a fourth aspect of the present invention, there is provided the piezoelectric vibration device according to the third aspect of the invention, wherein the piezoelectric vibrating piece is positioned in a direction away from the vibration portion with the two protrusions sandwiched between the maximum protrusions of the two protrusions. The sticking agent extends outward, and the sticking agent has the protrusion when viewed in a cross-section of the sticking agent, the substrate, the two protrusions, and the piezoelectric vibrating piece cut along the second direction. From the third edge on the vibration part side of the part to the fourth edge on the opposite side to the third edge,
Starting from the range up to the edge, it extends over the fourth edge, and is sandwiched between the protrusion and the piezoelectric vibrating piece at the position of the protrusion.

According to the fourth invention, in the second direction, the thickness of the sticking agent of the protrusion is made thicker in the vicinity of the fourth edge than in the vicinity of the starting point of the sticking agent. And as the thickness of the fixing agent increases, the amount of shrinkage during curing increases. Accordingly, the piezoelectric vibrating piece is subjected to a force that is sandwiched between the protrusion and the other side of the vibrating portion due to the difference in contraction between the vicinity of the starting point and the vicinity of the fourth edge.

As a result, the vibrating portion of the piezoelectric vibrating piece can easily secure a gap with the substrate. Thereby, the deformation | transformation in the 2nd direction of the vibration part of a piezoelectric vibrating piece can be reduced.

According to a fifth aspect of the present invention, in the piezoelectric vibration device according to any one of the first to fourth aspects, each of the two protrusions is an internal electrode to which a driving voltage for driving the piezoelectric vibrating piece is applied. A pair of excitation electrodes for exciting the vibrating portion based on the driving voltage is formed on the piezoelectric vibrating piece, and the driving voltage is extracted from the exciting electrode to the outside of the vibrating portion. A pair of lead electrodes led to the excitation electrode from the outside of the part is formed, and the lead electrodes are fixed to the internal electrodes with a conductive fixing agent.

According to the fifth aspect of the present invention, the connection between the electrodes and the fixation of the piezoelectric vibrating piece to the internal electrode are the same by connecting the lead electrode of the piezoelectric vibrating piece and the internal electrode with a conductive fixing agent. Since it can be performed at a location, space efficiency is improved and a smaller piezoelectric vibration device can be provided.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a piezoelectric vibration device, wherein two internal electrodes having a quadrilateral shape in plan view are formed on a substrate, the two internal electrodes project from one surface of the substrate, and the two internal electrodes A step of forming by screen printing so that each one side of
Forming a pair of excitation electrodes for exciting the piezoelectric vibration piece and a pair of extraction electrodes connected to the excitation electrode on the piezoelectric vibration piece, and among the four sides of each of the two internal electrodes, One side is the first side, the side opposite to the first side in the first direction connecting the two internal electrodes is the second side, and the remaining sides excluding the first side and the second side Of the two sides, when one side facing the same side of the two internal electrodes is the third side and the other side is the fourth side, a conductive adhesive is applied to each of the two internal electrodes. A region to be separated from the first side by a distance of three times the maximum thickness of the internal electrode that is closer to the second side and protrudes from the one surface of the internal electrode in the plan view. The first imaginary line and the third side from the third side by a distance of three times the maximum thickness. A second imaginary line spaced four sides side, said second side, said fourth
The sticking agent is applied so that the sticking agent is applied within a region surrounded by a side and within a range from each of the second side and the fourth side to the inside by a distance of three times the maximum thickness. A gap is formed between the piezoelectric vibrating piece and the one surface of the substrate, and the excitation electrode is moved along the second direction intersecting the first direction in a plan view. Positioned outside the third side, at each position of the two internal electrodes, positioned so that the ends of the pair of extraction electrodes are within the range, and each of the pair of extraction electrodes is And a step of mounting so as to connect to each of the two internal electrodes via the fixing agent.

Here, the inventor of the present invention has found that the distance from each side of the fixing agent applied to the internal electrode is three times the maximum thickness of the internal electrode as a value having the following effects. It is a thing.

According to the sixth aspect of the invention, the fixing agent is sandwiched between the internal electrode and the piezoelectric vibrating piece by setting the application range of the fixing agent and the mounting position of the piezoelectric vibrating piece as described above. At this time, since the internal electrode is formed by the screen printing method, the thickness of the electrode is smaller on the outer periphery than on the inner side of the internal electrode. That is, the distance between the piezoelectric vibrating piece and the internal electrode is wider on the outer periphery than on the inner side of the internal electrode.

Accordingly, the thickness of the fixing agent is thicker in the vicinity of the second side and the fourth side than in the vicinity of the maximum protrusion. And the amount of contraction of the fixing agent increases as the thickness increases. Therefore, the piezoelectric vibrating piece is pulled toward the second side in the first direction due to the difference in shrinkage between the vicinity of the maximum protrusion of the adhesive and the second side and the fourth side, and in the second direction. The force pulled to the fourth side works.

As a result, in the first direction, the excitation electrode portion (vibrating portion) of the piezoelectric vibrating piece formed so as to be located outside the third side of the internal electrode and the portion spanned between the internal electrodes of the piezoelectric vibrating piece. Is difficult to deform because of the tension that makes it flat. In addition, since the second vibrating portion is pulled toward the fourth side, the vibrating portion of the piezoelectric vibrating piece can easily secure a gap with the substrate.
Accordingly, it is possible to manufacture a piezoelectric vibration device that can reduce the deformation of the vibration portion of the piezoelectric vibrating piece in both the first direction and the second direction.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1A is a plan view of the piezoelectric vibration device 1 with the lid 7 removed, and FIG. 1B is a diagram in which the lid 7 taken along line AA in FIG. The sectional view of the state, FIG. 10C, is a sectional view of the state where the lid body 7 is attached at the NN line in FIG.

The piezoelectric vibration device 1 includes a package 2, a piezoelectric vibrating piece 3, an internal electrode 4a, an internal electrode 4b, a fixing agent 5, a pillow portion 6, a lid 7, a bonding material 8, and the like.
The package 2 includes a base portion 2a and a frame portion 2b, and is formed of an insulating material such as a ceramic having a thermal expansion coefficient close to that of a piezoelectric vibrating piece 3 described later. The base part 2a and the frame part 2b are integrated by sintering.

The piezoelectric vibrating reed 3 is obtained by cutting a quartz crystal having an X axis as an electric axis, a Y axis as a mechanical axis, and a Z axis as an optical axis in a direction having a predetermined angle with respect to the Z axis. It is formed by etching from a quartz wafer polished to a predetermined thickness corresponding to the vibration frequency. In this embodiment,
The piezoelectric vibrating piece 3 is an AT-cut quartz vibrating piece obtained by cutting a quartz ore in a direction of about 35 degrees with respect to the Z axis, and has a thickness of about 30 μm.

An excitation electrode 3 a is formed on the surface of the piezoelectric vibrating piece 3, and an excitation electrode 3 b is formed on the back surface. Further, the extraction electrode 3 c extends from the excitation electrode 3 a to the end of the fixed portion 3 e of the piezoelectric vibrating piece 3. Similarly, the extraction electrode 3 d extends from the excitation electrode 3 b to the fixed portion 3 e of the piezoelectric vibrating piece 3.
It extends to the end of the.
The extraction electrode 3c is formed so as to go from the front surface to the back surface. Extraction electrode 3
d is formed so as to wrap around from the back surface to the front surface. That is, the extraction electrode 3c and the extraction electrode 3d are arranged side by side on both the front surface and the back surface.

The internal electrodes 4 a and 4 b are provided on the inner surface 21 of the base portion 2 a of the package 2, the internal electrode 4 a is provided on the lead electrode 3 c of the piezoelectric vibrating piece 3, and the internal electrode 4 b is provided on the lead electrode 3 d on the piezoelectric vibrating piece 3.
They are formed at opposite positions. These internal electrodes 4 a and 4 b have a quadrilateral planar shape and are formed so as to protrude from the inner surface 21.
The internal electrodes 4a and 4b are arranged so that the first sides 42 face each other along the direction intersecting the direction connecting the excitation electrodes 3a and 3b of the piezoelectric vibrating piece 3 and the fixed portion 3e. The side opposite to the first side 42 is the second side 44, and of the remaining two sides, the excitation electrodes 3 a and 3 b of the piezoelectric vibrating piece 3.
The side on the side is the third side 41, and the side on the opposite side is the fourth side 43.

The fixing agent 5 is called a conductive adhesive in which conductive particles such as silver particles are added to a binder component made of a synthetic resin such as silicone, for example. It is applied close to the four sides 43 (details will be described later), and after placing the piezoelectric vibrating piece 3,
It is cured by being heated, and the piezoelectric vibrating piece 3 is fixed to the internal electrodes 4a and 4b.

As shown in FIG. 1B, the pillow portion 6 is formed on the inner surface 21 of the base portion 2 a of the package 2 so as to protrude from the inner surface 21. The pillow portion 6 supports the tip portion 3f so that the piezoelectric vibrating piece 3 does not tilt toward the base portion 2a until the fixing agent 5 is cured.
The lid 7 is made of a metal such as Kovar, or ceramic or glass, and hermetically seals the package 2 via a bonding material 8 such as low-melting glass.

The piezoelectric vibrating piece 3 is stretched between the internal electrode 4a and the internal electrode 4b with a gap between the piezoelectric vibrating piece 3 and the base portion 2a of the package 2. The piezoelectric vibrating reed 3 includes the internal electrode 4 along a direction in which the excitation electrodes 3a and 3b intersect the direction connecting the internal electrodes 4a and 4b in plan view.
It is located outside the third side 41 of a and 4b. At the same time, the piezoelectric vibrating reed 3 is applied to the application range of the fixing agent 5 on the internal electrodes 4a and 4b, and the extraction electrodes 3c and 3d are connected to the internal electrode 4.
It is mounted so that it may be connected to a and 4b through the sticking agent 5.
When a driving voltage is applied to the excitation electrodes 3a and 3b from the outside via the internal electrodes 4a and 4b, the fixing agent 5 and the extraction electrodes 3c and 3d, the piezoelectric vibrating piece 3 oscillates thickness shear vibration.

Here, the outline of the manufacturing process of the piezoelectric vibration device 1 will be described.
First, as shown in FIG. 2 (a), a conductive pattern to be used as the internal electrodes 4a, 4b and the pillow portion 6 is formed on the inner surface 21 of the base portion 2a of the package 2 by using a conductive paste such as silver, palladium, tungsten metallization or the like. And formed by screen printing.
Note that the internal electrodes 4a and 4b formed by the screen printing method are formed from the base portion 2a over the entire circumference of the internal electrodes as shown in FIG. 2B, which is an arrow view of FIG. The electrode thickness is not uniform, and a portion called “sag” (hereinafter referred to as a sag portion 45) is generated in which the electrode thickness gradually decreases from the inner side toward the outer periphery.

Next, as shown in FIG.2 (c), the frame part 2b of the package 2 is mounted on the base part 2a,
The base portion 2a and the frame portion 2b are sintered at about 800 ° C. for about 2 hours.
Next, a metal film such as gold or silver with nickel as a base is formed on the surface of the internal electrodes 4a and 4b by plating.
Next, the package 2 is placed on an index table (not shown), and an image recognition device (
The package 2 is positioned using a not-shown) or the like.

Next, as shown in FIG. 3, the fixing agent 5 is applied onto the internal electrodes 4a and 4b using a dispenser (not shown).
Here, the region where the fixing agent 5 is applied will be described. First, in each of the internal electrodes 4a and 4b, as shown in FIG. 4A, a first imaginary line 51 that is closer to the second side 44 by a distance L from the first side 42, and a distance from the third side 41. Second imaginary line 52 approaching the fourth side 43 side by L
And a third virtual line 53 that is closer to the first side 42 by a distance L from the second side 44, and a fourth virtual line 54 that is closer to the third side 41 by a distance L from the fourth side 43. . The region to which the fixing agent 5 is applied is a region surrounded by the first virtual line 51, the second virtual line 52, the second side 44, and the fourth side 43.

In other words, in each of the internal electrodes 4a and 4b, the first virtual line 51 and the first side 42
The region surrounded by the third side 41 and the fourth side 43, and the region surrounded by the second virtual line 52, the third side 41, the first side 42, and the second side 44 are fixed. This is a region where the agent 5 is not applied.
Further, the sticking agent 5 is applied to the essential area excluding the area surrounded by the first imaginary line 51, the second imaginary line 52, the third imaginary line 53, and the fourth imaginary line 54 from the application area, that is, the application. It is applied so as to be surely applied within a range from the second side 44 and the fourth side 43 to the inside by a distance L in the region. That is, for example, as shown in FIG. 3, the fixing agent 5 is applied so as to cover an essential area in the application area.

Here, the distance L is as shown in FIG. 4B, which is a cross-sectional view taken along line BB in FIG.
When the maximum thickness of each of the internal electrodes 4a and 4b is t, the distance L ≧ 3t. This is because the inventor of the present invention has found that the mass production variation generated by the sag portion 45 falls within approximately 3 t. In the present embodiment, since the maximum thickness of each of the internal electrodes 4a and 4b is about 20 μm, the distance L is set to a value of about 60 μm or more. The first
A region surrounded by the virtual line 51, the second virtual line 52, the third virtual line 53, and the fourth virtual line 54 is hereinafter referred to as a sag convergence region 55.

Next, the application range of the fixing agent 5 is inspected by an image recognition device or the like, and those that do not satisfy the application range are removed as defective products.
Further, in another process, the excitation electrodes 3a and 3b and the extraction electrodes 3c and 3d are formed on the piezoelectric vibrating piece 3 using a metal film such as gold or silver using a photolithography technique or the like.
Next, as shown in FIG. 5, the piezoelectric vibrating reed 3 is turned into a sag portion 45 (on the second side 44 and the fourth side 43 side of the internal electrodes 4 a and 4 b by an image recognition device or the like. 6), positioning is performed so as to be applied to the pillow portion 6, and the electrodes are placed on the internal electrodes 4 a and 4 b and the pillow portion 6.

Next, the fixing agent 5 is heated at about 200 ° C. for about 2 hours to cure the fixing agent 5 and fix the piezoelectric vibrating reed 3 to the internal electrodes 4a and 4b.
Next, a method of applying a drive signal to the excitation electrodes 3a and 3b via the internal electrodes 4a and 4b and vibrating the piezoelectric vibrating piece 3 to measure the frequency while cutting or thickening the excitation electrodes 3a and 3b. Thus, the frequency of the piezoelectric vibrating piece 3 is finely adjusted.

Next, as shown in FIG. 1B, the lid 7 is joined to the package 2 using a joining material 8 such as low melting point glass, and the package 2 is hermetically sealed. Through the above manufacturing process, the piezoelectric vibration device 1 is completed.
Here, as shown in FIG. 6A, the adhesive 5 is a direction in which the package 2, the internal electrodes 4a and 4b, and the piezoelectric vibrating piece 3 are connected to each other between the internal electrodes 4a and 4b. When the cross-sectional view cut along the line is viewed, the sagging convergence region 55 is between the first side 42 and the second side 44.
Starting from the inside, it extends over the second side 44 and is sandwiched between the sag portion 45 of each of the internal electrodes 4 a and 4 b and the piezoelectric vibrating piece 3.

Further, the adhesive 5 cuts the package 2, the internal electrodes 4 a and 4 b and the piezoelectric vibrating piece 3 along the line DD in FIG. 5 which is a direction intersecting the direction connecting the internal electrodes 4 a and 4 b. As shown in FIG. 6B, which is a cross-sectional view, it extends from the third side 41 to the fourth side 43, starting from the sagging convergence region 55 and extending to the fourth side 43, and the internal electrode 4a. 4b, and is sandwiched between the respective sag portions 45 and the piezoelectric vibrating piece 3.

By forming the piezoelectric vibration device 1 as described above, there are the following operations and effects.
FIG. 7 schematically shows a deformed shape of the piezoelectric vibrating piece 3 in the piezoelectric vibrating device 1 of the present embodiment. Note that the deformed shape is exaggerated for easy understanding.
7A is a cross-sectional view taken along the line DD in FIG. 5, FIG. 7B is a cross-sectional view taken along the line EE in FIG. 5, and FIG. FIG. 7D is a cross-sectional view taken along line GG in FIG. 5.

As shown in FIGS. 7A and 7D, the gap between the internal electrode 4 b and the piezoelectric vibrating piece 3 is wider in the sag portion 45 than in the sag convergence region 55.
Therefore, the thickness of the sticking agent 5 is less than the sagging convergence region 55 of the internal electrodes 4a and 4b.
Is thicker. As described above, when the fixing agent 5 is cured, the amount of shrinkage increases as the thickness increases.

For this reason, in the direction crossing the direction connecting the internal electrodes 4a, 4b, the fixing agent 5
Is fixed, the fixing portion 3e of the piezoelectric vibrating piece 3 has a contraction amount of the sag convergence region 55 and the sag portion 45 of the internal electrode 4b of the fixing agent 5 as indicated by an arrow in FIG. Due to the difference, it is pulled outside the internal electrode 4b along the sag portion 45 of the internal electrode 4b.
As a result, the distal end portion 3f of the piezoelectric vibrating piece 3 is pulled toward the outside of the internal electrode 4b on the fixed portion 3e side, so that it is easy to secure a gap with the pillow portion 6.

In the direction connecting the internal electrodes 4a and 4b, as shown in FIG.
On the frame 2b side of a and 4b, the sagging convergence region 55 of the fixing agent 5 in the internal electrodes 4a and 4b.
Due to the difference in contraction amount between the sag portion 45 and the sag portion 45, the fixed portion 3e of the piezoelectric vibrating piece 3 is indicated by an arrow,
Pulled outside the internal electrodes 4a and 4b.

As a result, a flat tension is applied between the internal electrodes 4a and 4b of the fixed portion 3e of the piezoelectric vibrating piece 3 so that it is not easily deformed. Accordingly, as shown in FIGS. 7B and 7C, the vibrating portion 3g and the tip portion of the piezoelectric vibrating piece 3 extending from the vicinity of the fixed portion 3e to the pillow portion 6 side of the piezoelectric vibrating piece 3 are provided. It is possible to easily suppress the deformation of 3f.
As described above, by making it easy to suppress deformation of the vibrating portion 3g of the piezoelectric vibrating piece 3 when the fixing agent is cured, the residual stress of the entire piezoelectric vibrating piece 3 is reduced, and temperature characteristics and long-term reliability are maintained. And the improved piezoelectric vibration apparatus 1 can be provided.

In addition, the connection between the extraction electrodes 3c and 3d and the internal electrodes 4a and 4b and the fixation of the piezoelectric vibrating piece 3 to the internal electrodes 4a and 4b are performed at the same place via the fixing agent 5 which is a conductive adhesive. Therefore, the space efficiency in the piezoelectric vibration device 1 is improved, and the piezoelectric vibration device 1 can be downsized.
In the present embodiment, the base portion 2a of the package 2 corresponds to the substrate, and the internal electrode 4a,
4b corresponds to two protrusions.

In the present embodiment, the application range of the sticking agent 5 starts from the inside of the sag convergence region 55, and the second
Although it covers the side 44 (the fourth side 43), as shown in FIG. 8, the fixing agent 5 may be applied so as to be within the essential region. According to this, the fixing portion 3e of the piezoelectric vibrating piece 3 is the same as described above.
Can be pulled outward, and the same effect as in the above embodiment can be obtained.

In the present embodiment, the application range of the fixing agent 5 is the range within the internal electrodes 4a and 4b.
As shown in FIG. 9, the adhesive 5 is applied to the outside of the internal electrodes 4 a and 4 b beyond the internal electrodes 4 a and 4 b, and the adhesive 5 is interposed between the piezoelectric vibrating piece 3 and the base portion 2 a of the package 2. It may be sandwiched. According to this, regardless of the presence or absence of the sag portion 45 of the internal electrodes 4a and 4b, the fixed portion 3e of the piezoelectric vibrating piece 3 can be pulled outward as in the above embodiment, and the same effect as in the above embodiment can be obtained. Obtainable.

In this embodiment, the shape of the side surfaces of the internal electrodes 4a and 4b has no step, but as shown in FIG. 10, the tip 3f side of the piezoelectric vibrating piece 3 is higher and the fixed portion 3e side of the piezoelectric vibrating piece 3 is higher. It may be a low stepped shape.
According to this, the fixed portion 3e side of the piezoelectric vibrating reed 3 has the internal electrode 4a,
The piezoelectric vibrating piece 3 is attracted to the first stage (lower stage) of 4b and the sag portion 49 of the second stage (higher stage) of the internal electrodes 4a, 4b serves as a fulcrum, as indicated by an arrow. When the force which lifts the front-end | tip part 3f side acts, it becomes easy to ensure a clearance gap between the front-end | tip parts 3f with respect to the pillow part 6.

Further, in the stepped internal electrodes 4a and 4b, as shown in FIG. 10B, the relationship between the fixing range W2 of the piezoelectric vibrating reed 3 and the second stage sag convergence range W1 of the internal electrodes 4a and 4b. May be set to 1/2 × W2 <W1 <W2.
By setting the sag convergence range W <b> 1 to the above range, the lifting of the tip portion 3 f of the piezoelectric vibrating piece 3 due to the shrinkage of the fixing agent 5 can be suppressed, and the interference between the piezoelectric vibrating piece 3 and the lid 7 can be suppressed. it can.

In the present embodiment, the AT-cut quartz crystal vibrating piece is used as the piezoelectric vibrating piece of the piezoelectric vibrating device. However, the present invention is not limited to this, and a tuning-fork type quartz vibrating piece may be used. The material of the piezoelectric vibrating piece is not limited to quartz, but may be ceramic, lithium tantalate, lithium niobate, or the like.

The figure explaining the structure of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining the manufacturing process of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining application | coating of the sticking agent in the manufacturing process of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining the application | coating range of the sticking agent in the manufacturing process of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining mounting of the piezoelectric vibration piece in the manufacturing process of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining the relationship between the internal electrode of the piezoelectric vibration apparatus in embodiment of this invention, a fixing agent, and a piezoelectric vibrating piece. The figure explaining the effect in embodiment of this invention. The figure explaining the other example of the application | coating range of the sticking agent of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining the further another example of the application | coating range of the sticking agent of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining another example of the piezoelectric vibration apparatus in embodiment of this invention. The figure explaining the subject of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Piezoelectric vibration apparatus, 2 ... Package, 2a ... Base part, 3 ... Piezoelectric vibration piece, 4a, 4b ...
Internal electrodes, 5 ... sticking agent, 21 ... inner surface.

Claims (6)

A substrate, two protrusions formed to protrude from one surface of the substrate, a piezoelectric vibrating piece spanned between the two protrusions and having a gap between the one surface, and the piezoelectric A fixing agent for fixing a vibrating piece to each of the two protrusions;
The piezoelectric vibrating piece extends outward from each of the two protrusions in a first direction connecting the protrusions, and the vibration part that generates the piezoelectric vibration of the piezoelectric vibrating piece is a plan view. In the second direction intersecting with the first direction, the first projection is formed to extend away from the two projections, starting from a position outside the two projections. When the cross-section of the sticking agent, the substrate, the two protrusions, and the piezoelectric vibrating piece cut along the first direction is viewed, the sticking agent is positioned at the two protrusions. In the range between the one edge on the side between the protrusions and the other edge, the starting point is beyond the other edge, outside the range, and outside the range, the substrate and the Being sandwiched between piezoelectric vibrating pieces The piezoelectric vibration device according to symptoms. The piezoelectric vibrating piece extends outward from each of the two protrusions in a direction away from the vibration part with the two protrusions interposed therebetween, and the adhesive, the substrate, and the two protrusions. When the cross section of the piezoelectric vibrating piece cut along the second direction is viewed, the fixing agent is at the position of the two protrusions from one edge of the protrusion on the vibration part side, Starting from within the range to the other edge opposite to the one edge, it extends beyond the other edge, extends beyond the range from the one edge to the other edge, and the range. The piezoelectric vibration device according to claim 1, wherein the piezoelectric vibration device is sandwiched between the substrate and the piezoelectric vibrating piece. A substrate, two protrusions formed to protrude from one surface of the substrate, a piezoelectric vibrating piece spanned between the two protrusions and having a gap between the one surface, and the piezoelectric A fixing agent for fixing a vibrating piece to each of the two protrusions;
Each of the two protrusions is formed so that the thickness of the protrusion from the one surface decreases as it goes from the inside to the outer periphery of the protrusion, and the piezoelectric vibrating piece is the two protrusions In the first direction connecting the largest protrusions with the largest thickness of the protrusions, the vibration part that extends outward from the largest protrusion part and generates piezoelectric vibration of the piezoelectric vibrating piece is a plane. When viewed from the outside, in a second direction intersecting with the first direction, it starts from a position outside each of the two protrusions and extends away from the two protrusions. When the cross-section of the fixing agent, the substrate, the two protrusions, and the piezoelectric vibrating piece cut along the first direction is viewed, the fixing agent has the two protrusions. At the position of the part, From the first edge to the second edge opposite to the first edge, starting from within the range from the maximum protrusion to the second edge, the second edge and the protrusion A piezoelectric vibration device characterized in that the piezoelectric vibration device is sandwiched between a portion and the piezoelectric vibrating piece. The piezoelectric vibrating piece extends outward from the maximum protrusion of each of the two protrusions in a direction away from the vibration part with the two protrusions interposed therebetween, and the adhesive agent, the substrate, and each of the two protrusions. When the cross section of the two protrusions and the piezoelectric vibrating piece cut along the second direction is viewed, the fixing agent is removed from the third edge of the protrusion on the vibration part side. And extending to the fourth edge on the opposite side, starting from the range from the maximum protrusion to the fourth edge, spanning the fourth edge, and at the position of the protrusion, The piezoelectric vibration device according to claim 3, wherein the piezoelectric vibration device is sandwiched between the piezoelectric vibration piece. Each of the two protrusions is an internal electrode to which a driving voltage for driving the piezoelectric vibrating piece is applied, and the piezoelectric vibrating piece has a pair of excitations for exciting the vibrating unit based on the driving voltage. An electrode is formed, and a pair of extraction electrodes is formed that is extracted from the excitation electrode to the outside of the vibration unit and guides the driving voltage from the outside of the vibration unit to the excitation electrode. 5. The piezoelectric vibration device according to claim 1, wherein the piezoelectric vibration device is fixed to each of the internal electrodes with a conductive fixing agent. Two internal electrodes having a quadrilateral shape in plan view are formed on the substrate so that the two internal electrodes protrude from one surface of the substrate and the one side of each of the two internal electrodes faces each other. Forming by a printing method;
Forming a pair of excitation electrodes for exciting the piezoelectric vibration piece and a pair of extraction electrodes connected to the excitation electrode on the piezoelectric vibration piece;
Of the four sides of each of the two internal electrodes, the one side is the first side, and the side opposite to the first side in the first direction connecting the two internal electrodes is the second side. When the other two sides excluding the first side and the second side are the third side and the other side is the fourth side of the two inner electrodes facing the same side, The area where the conductive adhesive is applied to each of the two internal electrodes is, in plan view, from the first side of the internal electrode to the second side.
A first imaginary line separated from the first side by a distance of three times the maximum thickness that is close to the side and protrudes from the one surface of the internal electrode, and a distance that is three times the maximum thickness from the third side The maximum thickness is within a region surrounded by the second imaginary line, the second side, and the fourth side that are separated only by the fourth side, and from each of the second side and the fourth side Applying the sticking agent so that the sticking agent is applied within a range up to the inside by a distance of three times the distance;
A gap is formed between the piezoelectric vibrating piece and one surface of the substrate, and the excitation electrode is arranged in a third direction of the two internal electrodes along a second direction intersecting the first direction in a plan view. Positioned outside the side, at each position of the two internal electrodes, positioned so that the ends of the pair of extraction electrodes are within the range, and each of the pair of extraction electrodes is positioned within the two internal electrodes And a step of mounting the electrodes so as to be connected to each of the electrodes via the fixing agent.

Images