JP2004242132A - Piezoelectric vibration device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable piezoelectric vibration device which prevents disconnection of an extraction electrode, forms an electrode with the higher flexibility of design and has stable electric properties. <P>SOLUTION: This piezoelectric vibration device 1 configured by forming a central portion, an outer frame portion and a step portion connecting the central portion and the outer frame portion integrally has an exciting electrode 21 and a first extraction electrode 23 formed in the central portion, and a second extraction electrode 25 formed in the central portion and the outer frame portion. The first extraction electrode extends toward a particular area where step portions with different surface directions adjoin each other. The second extraction electrode is formed on and connected electrically to the upper surface of the first extraction electrode in the particular area and formed from the particular area to an edge part of the outer frame portion of the piezoelectric vibration device via the respective step portions with different surface directions to constitute an external connection terminal. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a piezoelectric vibrating device represented by a quartz oscillator or the like. In particular, a mesa structure in which a central portion having a main vibrating portion, an outer frame portion formed so as to surround the central portion, and a step portion connecting the central portion and the outer frame portion are integrally formed of a piezoelectric material. Alternatively, the present invention relates to an electrode structure of a piezoelectric vibration device having an inverted mesa structure.
[0002]
[Prior art]
Higher frequencies of communication devices and higher operating frequencies of microcomputers are also demanding higher frequencies of piezoelectric vibrating devices such as quartz resonators and quartz filters. Generally, thickness shear vibration of an AT-cut quartz plate is often used as a quartz plate (quartz plate) corresponding to a higher frequency, and as is well known, the frequency is determined by the thickness of the quartz plate. It is inversely proportional to thickness. For example, when trying to obtain a fundamental vibration frequency of 600 MHz, an ultra-thin quartz plate of 3 μm or less is required. In the processing of such an ultra-thin plate, the polishing operation is difficult, and it is difficult to improve the production yield.
[0003]
In order to solve this problem, as disclosed in Patent Literature 1, a concave portion is formed in a central portion of a quartz vibrating plate by a processing technique such as etching, and a main vibrating portion (central portion which is thin-walled) is formed on a bottom portion of the concave portion. ), And a so-called inverted mesa configuration in which a vibration region is reinforced by a thick reinforcing portion (outer frame portion) around the step portion through a step portion has been proposed. This type of quartz vibrating plate has a configuration in which an excitation electrode and an extraction electrode are formed on a quartz vibrating plate having a thinned main vibrating portion and a reinforcing portion formed around the main vibrating portion. By adopting such a configuration, the main vibrating portion can be made considerably thinner than the conventional one, and the yield can be improved.
[0004]
[Patent Document 1]
JP-A-2-231808
[Problems to be solved by the invention]
By the way, in the above-mentioned crystal diaphragm, the extraction electrode has a step portion connecting the main vibrating portion and the outer frame portion, and when the extraction electrode is thin, a top portion of the step portion is used at the time of manufacturing or the like. At the (ridge), disconnection of the extraction electrode was sometimes caused. In particular, since the quartz vibrating plate is an anisotropic piezoelectric crystal, the etching speed is different depending on the etching direction (crystal axis). The order of the etching speed is Z ′> + X>−X> Y ′. (In the case of AT-cut quartz, a new axis shifted from the Z axis by θ ° is called Z ′, and the new axis is shifted by θ ° from the Y axis. The new axis is referred to as Y '.) For this reason, since the inclination angle of the stepped portion differs depending on the direction, the peak portion (ridge portion) that becomes an acute angle and the peak portion (ridge portion) that becomes an obtuse angle are mixed, and the disconnection rate of the extraction electrode at the step portion that becomes an acute angle is extremely high. Met. Patent Document 1 proposes that the above-described disconnection is prevented by forming an electrode on the entire surface on the side where the concave portion is formed.
[0006]
However, in the configuration of Patent Literature 1, since the electrode on one main surface is a full-surface electrode, there is also a region where the electrodes face each other even in the extraction electrode portion other than the excitation electrode. And adversely affect electrical characteristics such as CI value (crystal impedance), and it is difficult to obtain more stable electrical characteristics. Further, since the electrode on one main surface is a full-surface electrode, the degree of freedom in designing the excitation electrode, the extraction electrode, and the like is limited.
[0007]
Furthermore, since the configuration of Patent Document 1 can be applied only to a configuration in which a concave portion is formed only on one main surface, when the main vibrating portion is thin-walled, it is more stepped than when a concave portion is formed in both main surfaces. Since the depth of the portion becomes deeper, the processing time becomes longer as the frequency becomes higher (the thickness of the main vibrating portion is reduced), and the yield is likely to be reduced due to the surface roughness of the main vibrating portion.
[0008]
The present invention has been made in view of such a point, and an object of the present invention is to provide a piezoelectric vibrating device having a step portion connecting a main vibrating portion and an outer frame portion capable of coping with high frequency, and disconnection of an extraction electrode. An object of the present invention is to provide a highly reliable piezoelectric vibrating device in which the formation of electrodes with a higher degree of freedom in design can be performed while electrical characteristics are more stable.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a central part having a main vibrating part, an outer frame part formed so as to surround the central part, and a step part connecting the central part and the outer frame part. Is a piezoelectric vibration device integrally formed of a piezoelectric material, and is formed at an excitation electrode and a first extraction electrode formed at a central portion of the piezoelectric vibration device, and at a central portion and an outer frame portion of the piezoelectric vibration device. A second extraction electrode, wherein the first extraction electrode is extended toward a specific region in which step portions having different plane directions are close to each other, and the second extraction electrode is provided in the specific region. It is formed on and electrically connected to the upper surface of the first extraction electrode, and is formed from this specific region to the end of the outer frame portion of the piezoelectric vibration device via each stepped portion having the different surface direction. And an external connection terminal.
[0010]
More specifically, the central portion has a polygonal shape, and the specific region where the step portions having different surface directions approach each other is a corner portion of the central portion.
[0011]
Also, a piezoelectric vibrator in which a central portion provided with a main vibrating portion, an outer frame portion formed so as to surround the central portion, and a step portion connecting the central portion and the outer frame portion is integrally formed of a piezoelectric material. A device, wherein a part of the central portion is formed with a central extension portion extending to near an edge of the outer frame portion, and an excitation electrode formed at a central portion of the piezoelectric vibration device. A first extraction electrode, a second extension electrode formed on a central extension portion and an outer frame portion of the piezoelectric vibrating device, wherein the first extension electrode is provided in a plane direction of the central extension portion. Different step portions are extended toward a specific region adjacent to each other, and the second extraction electrode is formed on the upper surface of the first extraction electrode in the specific region and is electrically connected to the specific region. The piezoelectric vibration device is moved from a specific area through the steps having the different surface directions. Characterized by the between the ends of the outer frame portion formed by comprising constitute an external connection terminal.
[0012]
【The invention's effect】
According to the first aspect of the present invention, the extraction electrode that extends the excitation electrode of the piezoelectric vibration device to the external connection terminal is connected to the first extraction electrode that is formed integrally with the excitation electrode, and is externally connected via the step. By separately forming the second extraction electrodes that form the connection terminals and electrically connecting them, it is possible to form the electrodes in a separate process, so that the extraction electrodes that are less likely to be disconnected can be formed.
[0013]
Further, since the first extraction electrode and the second extraction electrode are extended only to a specific region where the step portions having different plane directions are close to each other and are electrically connected to each other, the first extraction electrode and the second extraction electrode are electrically connected to each other. Electrodes having different polarities do not face each other on the front and back surfaces, and variations in electrode formation do not adversely affect electrical characteristics such as a CI value (crystal impedance), thereby obtaining more stable electrical characteristics. Thus, an electrode having a higher degree of design freedom can be formed.
[0014]
In addition, since the second extraction electrode is formed at the end of the outer frame portion of the piezoelectric vibration device via each step portion having a different surface direction, at the top (ridge) of one step portion, Even if a part of the second extraction electrode is disconnected, conduction can be secured at another step. In particular, in the case of a quartz vibrating plate, the second extraction electrode passes not only through the top portion of the step portion that becomes acute but also through the top portion of the step portion that becomes more obtuse. At the top, the second extraction electrode is not disconnected, and stable conduction can be ensured.
[0015]
According to the second aspect of the present invention, in addition to the above-described functions and effects, the central portion has a polygonal shape, and a corner portion of the central portion is a specific region where the step portions having different surface directions are close to each other. By doing so, it is easy to perform positioning when forming each of the extraction electrodes, and it is possible to form electrodes with high accuracy.In addition, mechanical contact is less likely to occur than at the center of the top of the step, and the risk of disconnection is extremely high. It has a low configuration.
[0016]
According to the third aspect of the present invention, the extraction electrode for extending the excitation electrode of the piezoelectric vibrating device to the external connection terminal is connected to the first extraction electrode formed integrally with the excitation electrode, and externally via the step portion. By separately forming the second extraction electrodes that form the connection terminals and electrically connecting them, it is possible to form the electrodes in a separate process, so that the extraction electrodes that are less likely to be disconnected can be formed.
[0017]
Further, since the first extraction electrode and the second extraction electrode are extended only to a specific region where the stepped portions of the central extension portion having different plane directions are close to each other and are electrically connected to each other, the excitation is performed. Electrodes having different polarities do not face each other in a region other than the electrodes, and variations in electrode formation do not adversely affect electrical characteristics such as a CI value (crystal impedance). Characteristics can be obtained and an electrode can be formed with a higher degree of design freedom.
[0018]
Further, since the first extraction electrode and the second extraction electrode are formed in a central extension portion extending to a portion near the edge of the outer frame portion, a part of the central portion is formed in a plane direction. Are arranged in a state of being close to the respective extraction electrodes, so that mechanical contact at the top of the step is unlikely to occur and the risk of disconnection can be drastically reduced. Since a part of the central part is formed in the central extension part extended to near the edge of the outer frame part, the second part does not adversely affect the excitation electrode formed in the central part. Can be formed.
[0019]
Further, since the second extraction electrode is formed at the end of the outer frame portion of the piezoelectric vibration device via each step portion having a different center direction of the central extension portion, the top portion of one step portion ( Even if a part of the second extraction electrode is disconnected at the ridge portion, conduction can be secured at another step portion. In particular, in the case of a quartz vibrating plate, the second extraction electrode passes not only through the top portion of the step portion that becomes acute but also through the top portion of the step portion that becomes more obtuse. At the top, the second extraction electrode is not disconnected, and stable conduction can be ensured.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case will be described in which the present invention is applied to a quartz vibrating plate constituting an AT-cut quartz oscillator as a piezoelectric vibrating device.
[0021]
(First embodiment)
-Structure of crystal diaphragm 1-
FIG. 1 is a plan view of a quartz vibrating plate 1 according to a first embodiment of the present invention, and FIG. 2 is a bottom view of FIG. FIG. 3 is a sectional view taken along line AA in FIG. 4 to 6 are views showing the manufacturing method of the present embodiment.
[0022]
The quartz vibrating plate 1 according to the present embodiment is formed of, for example, a flat rectangular AT-cut quartz vibrating plate, and has a central portion 11 having an inverted mesa structure, an outer frame portion 12 surrounding the central portion 11, the central portion and the outer frame portion. And stepped portions 13 and 14 as internal side walls connecting them are integrally formed.
[0023]
In the central portion 11, for example, step portions 131, 132, 133, and 134 having different surface directions are formed as front surface side step portions 13, and as the rear surface side step portion 14, for example, step portions 141 having different surface directions. , 142, 143 and 144 are formed, and a rectangular concave portion forming an extremely thin main vibrating portion (piezoelectric vibrating region) is formed on each of the front and back main surfaces. The outer frame portion 12 is formed as a reinforcing portion having a thickness several times as large as that of the central portion. In the quartz vibrating plate of the present invention, the front and back directions are the Y-axis direction (the front side is the + Y ′ axis, and the back side is the −Y axis), and the direction in which the steps 131 and 133 extend is the quartz vibrating plate. (The direction of the step 131 is the + X axis, and the direction of the step 133 is the -X axis), and the direction in which the steps 132 and 134 extend is the Z ′ of the quartz vibrating plate. It is an axial direction (the direction of the step 132 is a + Z axis, and the direction of the step 134 is a -Z 'axis). The formation of such a concave portion is performed by a wet etching method described later.
[0024]
Excitation electrodes 21 and 22 are formed in the central portions of the concave portions on the front and back surfaces, respectively. The excitation electrode 21 is extended by a first extraction electrode 23 from an end toward a central corner 151 at which stepped portions 131 and 132 having different surface directions approach each other. It is formed to the corner 121 of the outer frame 12 via the stepped portions 131 and 132. The excitation electrode 22 has a first extraction electrode 24 extending from an end toward a corner 164 at a central portion where stepped portions 141 and 144 having different plane directions are close to each other, and is close to the corner. It is formed to the corner 122 of the outer frame 12 via the step portions 141 and 144 that are formed. These electrodes are formed by a vacuum deposition method or the like, and each electrode material is, for example, a material in which gold is laminated on the upper surface of chromium.
[0025]
Further, at the corners 121 and 122 of the outer frame portions on the front and back surfaces, second extraction electromagnets 25 and 26 which are electrically connected to the excitation electrodes 21 and 22 and constitute external connection terminals are formed. I have. These second extraction electrodes are formed in separate steps after the excitation electrode and the first extraction electrode are formed. The second extraction electrode 25 passes through the stepped portions 131 and 132 from the vicinity of the central corner portion 151 so as to overlap with a part of the first extraction electrode 23 at the upper portion. Thus, the external connection terminal is formed at the corner 121 of the outer frame 12. The second extraction electrode 26 passes through the steps 143 and 144 from near the corner 163 at the center to approach the corner so as to overlap a part of the first extraction electrode 24 at the upper part. Thus, it is formed on the corner 122 of the outer frame 12 to form an external connection terminal. These electrodes are formed by a vacuum deposition method or the like, and each electrode material is, for example, a material in which silver is laminated on the upper surface of chromium and chromium is further laminated on the upper surface. It is preferable that these second extraction electrodes are formed wider than the width of the first extraction electrodes.
[0026]
With the above configuration, since the first extraction electrode and the second extraction electrode are separately configured, for example, the second extraction electrode can be formed in another process closer to the final process. In addition, it is possible to form an extraction electrode that is less likely to be disconnected. Further, since the second extraction electrode is formed at the end of the outer frame portion of the piezoelectric vibration device via two step portions having different surface directions, at the top (ridge) of one step portion, Even if a part of the second extraction electrode is disconnected, conduction can be secured at another step. In particular, in the case of using a quartz vibrating plate as in this embodiment, the second extraction electrode does not pass only through the tops of the tops of the steps 132 and 144 that become acute, but the steps that become more obtuse. Since it also passes through the tops of 131 and 143, the second extraction electrode does not break at the top of the step portion on the obtuse angle side, and stable conduction can be secured.
[0027]
The role of the second extraction electrode is to conduct to the first extraction electrode, and to be connected to an external electrode pad of a ceramic package described later via a conductive bonding material as an external connection terminal. Therefore, as in the present invention, the excitation electrode and the first extraction electrode are made of chromium + gold, and the second extraction electrode is made of chromium + silver + chromium, whereby the first extraction electrode and the second extraction electrode are made. The continuity with the electrodes is stable, and the connection with the conductive bonding material (especially silicon-based) is good, so the continuity with the external electrode pads of the ceramic package is also stabilized.
[0028]
Then, although not shown, such a piezoelectric vibration device is housed in a package made of ceramics such as alumina, and is electrically connected to external electrode pads of the ceramic package in order to lead the external connection terminals to the outside. Then, a surface mount type crystal resonator can be obtained by airtight bonding with the upper surface of the package with the cover plate.
[0029]
In the above-described embodiment, the first extraction electrode extends only at one corner of the square central portion as a specific area where the step portions having different plane directions are close to each other, and the second extraction electrode and the second extraction electrode are electrically connected to each other. Although it is electrically connected, it may be another polygonal shape as the center part, and the first extraction electrode may be extended to a plurality of corners and electrically connected to the second extraction electrode. .
[0030]
-Processing method of crystal diaphragm 1-
Next, a method of processing the quartz vibrating plate 1 according to the above embodiment will be described with reference to FIGS.
[0031]
Fig. 4 <Etching of quartz plate>
1- A resist film MR having a two-layer structure of Cr and Au is deposited on the entire front and back surfaces of the quartz vibrating plate 1.
2- Form a negative type resist film NR on the upper surface.
3- Using a photolithographic technique, an area excluding an area corresponding to the central portion 11 on the front and back surfaces of the quartz vibrating plate 1 is exposed and developed.
4-Metal etching is performed on the resist film MR (Au and Cr) in a region corresponding to the central portion 11 using an etchant.
5-By removing the negative type resist film NR and performing wet etching with an etching solution such as a hydrofluoric acid + ammonium fluoride solution, a thin central portion 11, step portions 13 and 14 (not shown), And the outer frame part 12 is formed.
6- Metal etching is performed on the entire surface of the resist film MR using an etchant.
[0032]
Fig. 5 <Formation of excitation electrode and first extraction electrode>
7- After the above-described process, an electrode film M1 having a two-layer structure of Cr and Au is deposited on the entire front and back surfaces of the quartz vibrating plate 1.
8- Form a positive type resist film PR on the upper surface.
Using 9-photolithography technology, regions other than regions corresponding to the excitation electrodes 21 and 22 (not shown) and the first extraction electrodes 23 and 24 (not shown) are exposed and developed.
10- Metal etching is performed on the electrode film M1 (Au and Cr) in the region using an etchant.
11-Removing the positive type resist film PR.
[0033]
FIG. 6 <Second electrode formation>
12-After the above-described steps, Cr and Ag are applied from the vicinity of the corner 151 or 164 (not shown) at the center of the quartz vibrating plate 1 to the corner 121 or 122 (not shown) of the outer frame 12. The second extraction electrodes 25 and 26 are formed by depositing an electrode film M2 having a three-layer structure of Cr and Cr. At this time, since the second extraction electrode is also formed on the side end surface of the outer frame portion of the quartz vibrating plate, the configuration is easy to handle as an external connection terminal.
[0034]
Through the above steps, as shown in FIGS. 1 to 3, the crystal diaphragm 1 having the central portion 11 and the outer frame portion 12 connected by the step portions 13 and 14 surrounding the central portion 11 is formed.
[0035]
(Second Embodiment)
Next, a second embodiment will be described. This embodiment is a modification of the shape of the central portion 2, and other configurations are the same as those of the above-described first embodiment. Therefore, only the differences from the first embodiment will be described here.
[0036]
FIG. 7 is a plan view of a quartz plate 1 according to a second embodiment of the present invention, and FIG. 8 is a bottom view of FIG. FIG. 9 is a sectional view taken along line BB in FIG.
As shown in this figure, the quartz vibrating plate 1 according to the present embodiment has a center portion 11 having an inverted mesa structure, an outer frame portion 12 surrounding the center portion, and step portions 13 and 14 connecting the center portion and the outer frame portion. And centrally extending portions 111 and 112 in which a part of the central portion 11 extends to the vicinity of an edge of the outer frame portion 12 on the same plane as one main surface of the central portion. Is provided.
[0037]
The central extension portion 111 has step portions 1311 and 1312 formed continuously from the portions adjacent to the step portions 131 and 132 on the front surface side, and the step portions 1311 and 1312 are further formed near the corner portion 121 of the outer frame portion. The step 1313 is formed at the center portion, so that a portion of the central portion extends to the vicinity of the edge of the outer frame portion on the same plane (same depth) as the front side of the central portion.
[0038]
The central extending portion 112 is formed with steps 1441 and 1442 continuously from the portions adjacent to the steps 141 and 144 on the front surface side and adjacent to the steps 141 and 144, and further near the corner 122 of the outer frame portion. The step portion 1443 is formed at the center portion, so that a part of the center portion extends to the vicinity of the edge of the outer frame portion on the same plane (same depth) as the back side of the center portion.
[0039]
As described above, the quartz vibrating plate 1 according to the present embodiment has a rectangular concave portion forming an ultra-thin main vibrating portion (piezoelectric vibrating region) on each of the front and back main surfaces, and a part of the concave portion is an end of the outer frame portion. A concave portion extending to near the edge is formed. The formation of such a concave portion is performed by a wet etching method.
[0040]
Excitation electrodes 21 and 22 are formed in the central portions of the concave portions on the front and back surfaces, respectively. The excitation electrode 21 is extended from an end toward a step 1313 which is an end of the central extension 112 by the first extraction electrode 23. The excitation electrode 22 is extended from the end toward the step 1443 which is the end of the central extension 112 by the first extraction electrode 24. These electrodes are formed by a vacuum deposition method or the like, and each electrode material is, for example, a material in which gold is laminated on the upper surface of chromium.
[0041]
Further, at the corners 121 and 122 of the outer frame portions on the front and back surfaces, second extraction electromagnets 25 and 26 which are electrically connected to the excitation electrodes 21 and 22 and constitute external connection terminals are formed. I have. These second extraction electrodes are formed in a separate step after the excitation electrode and the first extraction electrode are formed. The second extraction electrode 25 is formed so as to overlap a part of the first extraction electrode 23 at an upper portion, from a portion near an end of the central extension portion 111 to a position close to an end of the central extension portion. Via the parts 1311, 1312, 1313, they are formed on the corners 121 of the outer frame part 12 to constitute external connection terminals. The second extraction electrode 26 is formed so as to overlap a part of the first extraction electrode 24 at an upper portion from a portion near an end of the central extension 112 to an end of the center extension. It is formed on the corner 122 of the outer frame 12 via the parts 1441, 1442, 1443 to constitute an external connection terminal. These electrodes are formed by a vacuum deposition method or the like, and each electrode material is, for example, a material in which silver is laminated on the upper surface of chromium and chromium is further laminated on the upper surface. It is preferable that these second extraction electrodes are formed wider than the width of the first extraction electrodes.
[0042]
With the above configuration, since the first extraction electrode and the second extraction electrode are separately configured, for example, the second extraction electrode can be formed in another process closer to the final process. In addition, it is possible to form an extraction electrode that is less likely to be disconnected. Further, since the second extraction electrode is formed to the end of the outer frame portion of the piezoelectric vibration device via three step portions having different surface directions close to the end of the central extension portion, one second extraction electrode is formed. Even if a part of the second extraction electrode is disconnected at the top (ridge) of the step, conduction can be ensured at another step. In particular, in the present embodiment, since a part of the central portion is formed in the central extension portion extending to near the edge of the outer frame portion, a step portion having a different surface direction is formed by each of the extraction electrodes. , And mechanical contact at the top of the stepped portion is unlikely to occur, so that the risk of disconnection can be drastically reduced. Since a part of the central part is formed in the central extension part extended to near the edge of the outer frame part, the second part does not adversely affect the excitation electrode formed in the central part. Can be formed.
[0043]
In the above-described embodiment, an example is described in which a central extension is formed at one corner of a square central portion, but a central extension is formed at a side of the square central portion. Alternatively, a plurality of central extension portions may be formed, and the first extraction electrode may extend to the plurality of central extension portions, and may be electrically connected to the second extraction electrode.
[0044]
-Other embodiments-
In each of the embodiments described above, the concave portion (step portion) is formed on the front and back main surfaces, but the present invention is also applied to the case where the concave portion (step portion) is formed only on one of the front and back main surfaces. it can. In addition, an inverted mesa in which a thin center portion, a thick outer frame portion formed so as to surround the center portion, and a step portion connecting the center portion and the outer frame portion are integrally formed by a quartz vibrating plate. Although the structure is described, a thick central portion, a thin outer frame portion formed so as to surround the central portion, and a step portion connecting the central portion and the outer frame portion are integrally formed by a quartz vibrating plate. The present invention is also applicable to a formed mesa structure. In addition, a step portion may be formed between the center portion and the outer frame portion as a step-like inner side wall, so that even when stress acts on the outer frame portion, it can be easily relieved. As a result, local stress concentration can be avoided. Further, in each of the embodiments described above, the case where the quartz vibrating plate is adopted as the piezoelectric vibrating device has been described. The present invention is not limited to this, and is applicable to a piezoelectric vibration device made of another piezoelectric material.
[Brief description of the drawings]
FIG. 1 is a plan view of a crystal diaphragm according to a first embodiment.
FIG. 2 is a bottom view of FIG. 1;
FIG. 3 is a sectional view taken along line AA in FIG. 1;
FIG. 4 is a diagram showing a manufacturing method according to the first embodiment.
FIG. 5 is a diagram showing a manufacturing method according to the first embodiment.
FIG. 6 is a view showing a manufacturing method according to the first embodiment;
FIG. 7 is a plan view of a quartz plate according to a second embodiment.
FIG. 8 is a bottom view of FIG. 7;
FIG. 9 is a sectional view taken along the line BB in FIG. 7;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Quartz diaphragm 11 Center part 12 Outer frame parts 13, 14 Step part

Claims (3)

A piezoelectric vibration device in which a central portion having a main vibrating portion, an outer frame portion formed so as to surround the central portion, and a step connecting the central portion and the outer frame portion are integrally formed of a piezoelectric material. So,
An excitation electrode and a first extraction electrode formed at the center of the piezoelectric vibration device, and a second extraction electrode formed at the center and the outer frame of the piezoelectric vibration device;
The first extraction electrode extends toward a specific region in which step portions having different plane directions are close to each other,
The second extraction electrode is formed on the upper surface of the first extraction electrode in the specific region and is electrically connected to the second extraction electrode, and from the specific region via each step portion having a different surface direction. A piezoelectric vibration device, which is formed on an end of an outer frame portion of the piezoelectric vibration device to form an external connection terminal. 2. The piezoelectric vibrating device according to claim 1, wherein the central portion has a polygonal shape, and the specific region where the step portions having different surface directions approach each other is a corner portion of the central portion. A piezoelectric vibration device in which a central portion having a main vibrating portion, an outer frame portion formed so as to surround the central portion, and a step connecting the central portion and the outer frame portion are integrally formed of a piezoelectric material. So,
A part of the central portion is formed with a central extension portion extended to near an edge of the outer frame portion,
An excitation electrode and a first extraction electrode formed at the center of the piezoelectric vibration device, and a second extraction electrode formed at the center extension and the outer frame of the piezoelectric vibration device;
The first extraction electrode is extended toward a specific region in which step portions having different surface directions of the central extension portion are close to each other,
The second extraction electrode is formed on the upper surface of the first extraction electrode in the specific region and is electrically connected to the second extraction electrode, and from the specific region via each step portion having a different surface direction. A piezoelectric vibration device, which is formed on an end of an outer frame portion of the piezoelectric vibration device to form an external connection terminal.

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