JP5552878B2 - Vibrating piece, vibrating device and electronic device - Google Patents

Description

  The present invention relates to a resonator element, a vibration device, and an electronic apparatus.

As a vibrating device such as a crystal oscillator, a vibrating device including a tuning fork type vibrating piece including a plurality of vibrating arms is known (for example, see Patent Document 1).
For example, the resonator element disclosed in Patent Document 1 includes a base, three vibrating arms extending from the base so as to be parallel to each other, and a lower electrode film, a piezoelectric film, and an upper electrode film on each vibrating arm. And a piezoelectric element formed and formed in this order. In such a vibrating piece, the piezoelectric element is expanded and contracted by applying an electric field between the lower electrode film and the upper electrode film, and the vibrating arm is flexibly vibrated in the thickness direction of the base. .
A resonator element using such a piezoelectric element has the advantage of being easily reduced in size and weight.

By the way, in the piezoelectric element provided in such a resonator element, when the area of the upper electrode film and the lower electrode film is reduced, the mechanical coupling coefficient is reduced, while the area of the upper electrode film and the lower electrode film is increased. As a result, it is known that the electric parallel capacitance increases.
Therefore, for the purpose of balancing these, conventionally, as disclosed in Patent Document 1, the piezoelectric film is provided so as to cover the proximal end half of the vibrating arm together with the upper electrode film and the lower electrode film. The portion on the tip side of the vibrating arm is not covered with the piezoelectric film.

However, in such a vibrating piece, since the piezoelectric film is partially formed on the vibrating arm as described above, the proximal end portion (the portion covered by the piezoelectric film) and the distal end of the vibrating arm The rigidity of the side portion (the portion not covered with the piezoelectric film) is different, and an unnecessary vibration mode is generated.
This unnecessary vibration mode is due to the vibration of the vibrating arm being bent near the tip of the piezoelectric film. A temperature rise corresponding to the linear expansion coefficient of the material occurs in such a bent portion of the vibrating arm. Therefore, the conventional resonator element has a problem that the internal loss increases and the Q value cannot be sufficiently increased.
Such a problem becomes particularly prominent when the material constituting the piezoelectric film has a high elastic constant.

JP 2009-5022 A

  An object of the present invention is to provide a resonator element having good oscillation characteristics, and a resonator device and an electronic apparatus including the resonator element.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.
The resonator element according to the invention includes a base,
At least one vibrating arm extending from the base;
A first electrode layer, a piezoelectric layer, and a second electrode layer are laminated in this order on the vibrating arm, and a voltage is applied between the first electrode layer and the second electrode layer. A piezoelectric element that expands and contracts the piezoelectric layer and flexibly vibrates the vibrating arm,
The piezoelectric layer is provided from the base side to the vicinity of the tip of the vibrating arm.
As a result, it is possible to prevent a portion where the rigidity changes abruptly in the middle of the extending direction (longitudinal direction) of the vibrating arm. Therefore, it is possible to prevent generation of unnecessary vibration modes of the resonator element and increase the Q value of the resonator element. As a result, the oscillation characteristics of the resonator element can be improved.

In the resonator element according to the aspect of the invention, the end of at least one of the first electrode layer and the second electrode layer opposite to the base is opposite to the base of the piezoelectric layer. It is preferable that it is located in the said base part side rather than the edge.
Thereby, the driving force of the piezoelectric element can be transmitted to a partial range in the extending direction of the vibrating arm.

In the resonator element according to the aspect of the invention, the end of at least one of the first electrode layer and the second electrode layer on the side opposite to the base portion may be near the center in the extending direction of the vibrating arm. It is preferable that it is located in.
Accordingly, by applying the driving force of the piezoelectric element to the proximal end portion of the vibrating arm, the vibrating arm can be efficiently vibrated by the piezoelectric element. In addition, it is possible to prevent the driving force of the piezoelectric element from acting on the tip of the vibrating arm. Therefore, it is possible to prevent an unnecessary vibration mode from occurring in the vibrating arm.

In the resonator element according to the aspect of the invention, it is preferable that the piezoelectric layer is provided over the entire region in the extending direction of the vibrating arm.
Thereby, the bending rigidity of the vibrating arm can be made uniform.
In the resonator element according to the aspect of the invention, the vibrating arm has a plate shape,
The piezoelectric layer is preferably provided over the entire surface of one plate surface of the vibrating arm.
Thereby, the bending rigidity of a vibrating arm can be equalized easily and reliably.

In the resonator element according to the aspect of the invention, it is preferable that an end of the piezoelectric layer on the base side is provided so as to straddle a boundary portion between the vibrating arm and the base.
Thereby, the driving force of the piezoelectric element can be efficiently transmitted to the vibrating arm. In addition, a sudden change in rigidity at the boundary between the vibrating arm and the base can be mitigated. Therefore, the Q value of the resonator element can be increased.
In the resonator element according to the aspect of the invention, it is preferable that the thickness of the end portion of the piezoelectric layer opposite to the base portion gradually decreases from the base end side to the tip end side of the vibrating arm.
Thereby, even if the tip of the piezoelectric layer does not coincide with the tip of the vibrating arm, it is possible to prevent the rigidity from changing suddenly in a part of the extending direction of the vibrating arm.
In the resonator element according to the aspect of the invention, it is preferable that an elastic constant of a material forming the piezoelectric layer is larger than an elastic constant of a material forming the vibrating arm.
In such a case, the piezoelectric layer has a great influence on the vibration characteristics of the vibrating arm. Therefore, the effect becomes remarkable by applying the present invention in such a case.

In the resonator element according to the aspect of the invention, a plurality of the vibrating arms are provided side by side in a direction orthogonal to the extending direction of the vibrating arm and the vibration direction of the bending vibration of the vibrating arm by the piezoelectric element. It is preferable that the two vibrating arms bend and vibrate in opposite directions.
Thereby, a vibration piece with less vibration leakage can be realized.
In the resonator element according to the aspect of the invention, it is preferable that the vibrating arm is made of quartz.
Thereby, the vibration characteristic (especially frequency temperature characteristic) of a vibrating arm can be made excellent. Further, the vibrating arm can be formed with high dimensional accuracy by etching.

The vibrating device of the present invention includes the vibrating piece of the present invention,
And a package for housing the resonator element.
Thereby, a vibration device having excellent oscillation characteristics can be provided.
An electronic apparatus according to the present invention includes the vibration device according to the present invention.
Thereby, an electronic device having excellent reliability can be provided.

It is sectional drawing which shows the vibration device which concerns on 1st Embodiment of this invention. It is a top view which shows the vibration device shown in FIG. FIG. 2 is a bottom view showing a vibrating piece provided in the vibrating device shown in FIG. 1. It is the sectional view on the AA line in FIG. FIG. 3 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG. 2. FIG. 3 is a perspective view for explaining the operation of the resonator element shown in FIG. 2. 2A is a schematic cross-sectional view for explaining flexural vibration of the vibrating arm of the vibrating piece shown in FIG. 2, and FIG. 2B is a schematic cross-sectional view for explaining bending vibration of the vibrating arm of the conventional vibrating piece. FIG. 2A is a schematic cross-sectional view for explaining flexural vibration of the vibrating arm of the vibrating piece shown in FIG. 2, and FIG. 2B is a schematic cross-sectional view for explaining bending vibration of the vibrating arm of the conventional vibrating piece. FIG. It is a top view which shows the vibration device which concerns on 2nd Embodiment of this invention. FIG. 10 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG. 9. It is sectional drawing which shows the vibration device which concerns on 3rd Embodiment of this invention. FIG. 12 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG. 11. It is sectional drawing which shows the vibration device which concerns on 4th Embodiment of this invention. FIG. 14 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG. 13. It is sectional drawing which shows the vibration device which concerns on 5th Embodiment of this invention. It is the sectional view on the AA line in FIG. It is an electronic apparatus (notebook type personal computer) provided with the vibration device of this invention. An electronic apparatus (mobile phone) including the vibration device of the invention. It is an electronic apparatus (digital still camera) provided with the vibration device of the present invention.

Hereinafter, a resonator element and a vibration device of the present invention will be described in detail based on embodiments shown in the accompanying drawings.
<First Embodiment>
1 is a cross-sectional view showing the vibration device according to the first embodiment of the present invention, FIG. 2 is a top view showing the vibration device shown in FIG. 1, and FIG. 3 is a vibration provided in the vibration device shown in FIG. 4 is a bottom view showing the piece, FIG. 4 is a sectional view taken along line AA in FIG. 2, FIG. 5 is a partial sectional perspective view showing the vibrating arm provided in the vibrating piece shown in FIG. 2, and FIG. FIG. 7A and FIG. 8A are schematic cross-sectional views for explaining flexural vibration of the vibrating arm of the vibrating piece shown in FIG. 2, respectively. FIGS. 7B and 8B are schematic cross-sectional views for explaining bending vibration of the vibrating arm of the conventional vibrating piece. In each figure, for convenience of explanation, an X axis, a Y axis, and a Z axis are illustrated as three axes orthogonal to each other. In the following, the direction parallel to the Y-axis (first direction) is the Y-axis direction, the direction parallel to the X-axis (second direction) is the “X-axis direction”, and the direction parallel to the Z-axis (third Is referred to as the Z-axis direction. In the following description, for convenience of explanation, the upper side in FIG. 1 is referred to as “upper”, the lower side as “lower”, the right side as “right”, and the left side as “left”.
A vibrating device 1 illustrated in FIG. 1 includes a vibrating piece 2 and a package 3 that houses the vibrating piece 2.

Hereinafter, each part which comprises the vibration device 1 is demonstrated in detail sequentially.
(Vibration piece)
First, the resonator element 2 will be described.
The resonator element 2 is a three-leg tuning fork type resonator element as shown in FIG. The vibration piece 2 includes a vibration substrate 21, piezoelectric elements 22, 23, and 24 and connection electrodes 41 and 42 provided on the vibration substrate 21.
The vibration substrate 21 has a base portion 27 and three vibration arms 28, 29, and 30.

The constituent material of the vibration substrate 21 is not particularly limited as long as it can exhibit desired vibration characteristics, and various piezoelectric materials and various non-piezoelectric materials can be used.
Examples of the piezoelectric material include crystal, lithium tantalate, lithium niobate, lithium borate, and barium titanate. In particular, the piezoelectric material constituting the vibration substrate 21 is preferably a crystal that is a single crystal that is chemically stable and has good temperature characteristics. When the vibration substrate 21 is made of quartz, the vibration characteristics (particularly the frequency temperature characteristic) of the vibration substrate 21 can be made excellent. In addition, the vibration substrate 21 can be formed with high dimensional accuracy utilizing the anisotropic etching characteristics of quartz.

  Examples of the non-piezoelectric material include silicon and quartz glass. In particular, silicon is preferable as the non-piezoelectric material constituting the vibration substrate 21. When the vibration substrate 21 is made of silicon, a vibration substrate 21 having excellent vibration characteristics can be realized at a relatively low cost. In addition, it is easy to integrate the resonator element 2 and other circuit elements by forming an integrated circuit on the base 27. In addition, if the material is silicon, a fine processing technique used in silicon device manufacturing can be used, so that the vibration substrate 21 can be formed with higher dimensional accuracy.

In such a vibration substrate 21, the base 27 has a substantially plate shape with the Z-axis direction as the thickness direction. As shown in FIGS. 1 and 3, the base portion 27 includes a thin portion 271 formed to be thin and a thick portion 272 formed to be thicker than the thin portion 271. They are arranged side by side in the axial direction.
The thin portion 271 is formed to have a thickness equal to each of the vibrating arms 28, 29, and 30 described later. Therefore, the thick portion 272 is a portion whose thickness in the Z-axis direction is larger than the thickness of each vibrating arm 28, 29, 30 in the Z-axis direction.
By forming the thin portion 271 and the thick portion 272 as described above, the thickness of the vibrating arms 28, 29, 30 is reduced to improve the vibration characteristics of the vibrating arms 28, 29, 30, and the vibrating piece 2 The handling property at the time of manufacturing can be made excellent.

Three vibrating arms 28, 29, and 30 are connected to the opposite side of the thin portion 271 of the base portion 27 to the thick portion 272.
The vibrating arms 28 and 29 are connected to both ends of the base 27 (thin wall portion 271) in the X-axis direction, and the vibrating arm 30 is connected to a center portion of the base 27 (thin wall portion 271) in the X-axis direction. Yes.
The three vibrating arms 28, 29, and 30 are provided so as to extend from the base 27 so as to be parallel to each other. More specifically, the three vibrating arms 28, 29, and 30 extend from the base 27 in the Y-axis direction (the arrow direction of the Y-axis) and are provided side by side in the X-axis direction.

Each of the vibrating arms 28, 29, and 30 has a longitudinal shape, an end portion (base end portion) on the base portion 27 side is a fixed end, and an end portion (tip end portion) opposite to the base portion 27 is a free end. Become.
The vibrating arms 28, 29, and 30 each have a plate shape having a pair of plate surfaces (main surfaces) facing each other.
The vibrating arms 28 and 29 are formed so as to have the same width, and the vibrating arm 30 is formed so as to be twice as wide as the vibrating arms 28 and 29. Thus, by arranging the mass of the vibrating arms 28 and 29 and the vibrating arm 30 and balancing the center of gravity, the vibrating arms 28 and 29 are flexibly vibrated in the Z-axis direction, and the vibrating arm 30 is made to vibrate with the vibrating arms 28 and 29. When bending vibration is performed in the opposite direction (in reverse phase) in the Z-axis direction, vibration leakage can be reduced. However, in the present invention, the widths of the vibrating arms 28, 29, and 30 are not limited to those described above, and can be applied to vibrating pieces having the same arm width, for example.

  In addition, each of the vibrating arms 28, 29, and 30 has a constant width over the entire area in the longitudinal direction. It should be noted that a mass portion (hammer head) having a larger cross-sectional area than the base end portion may be provided at each distal end portion of the vibrating arms 28, 29, and 30 as necessary. In this case, the vibrating piece 2 can be made smaller, and the bending vibration frequency of the vibrating arms 28, 29, and 30 can be further reduced.

  As shown in FIG. 4, the piezoelectric element 22 is provided on such a vibrating arm 28, the piezoelectric element 23 is provided on the vibrating arm 29, and further, on the vibrating arm 30. A piezoelectric element 24 is provided. Thereby, each vibrating arm 28, 29, 30 can be flexibly vibrated in the Z-axis direction. In addition, since each vibrating arm 28, 29, 30 does not have to have piezoelectricity, the range of selection of the material of each vibrating arm 28, 29, 30 is expanded. Therefore, the resonator element 2 having desired vibration characteristics can be realized relatively easily.

The piezoelectric element 22 has a function of causing the vibrating arm 28 to bend and vibrate in the Z-axis direction by expanding and contracting by applying a voltage (that is, expanding and contracting due to the piezoelectric effect). Further, the piezoelectric element 23 has a function of expanding and contracting by applying a voltage to bend and vibrate the vibrating arm 29 in the Z-axis direction. In addition, the piezoelectric element 24 has a function of expanding and contracting by applying a voltage to bend and vibrate the vibrating arm 30 in the Z-axis direction.
As shown in FIG. 4, the piezoelectric element 22 has a first electrode layer 221, a piezoelectric layer (piezoelectric thin film) 222, and a second electrode layer 223 stacked in this order on the vibrating arm 28. Configured.
Similarly, the piezoelectric element 23 is configured by laminating a first electrode layer 231, a piezoelectric layer (piezoelectric thin film) 232, and a second electrode layer 233 on the vibrating arm 29 in this order. The piezoelectric element 24 is configured by laminating a first electrode layer 241, a piezoelectric layer (piezoelectric thin film) 242, and a second electrode layer 243 in this order on the vibrating arm 30.

Hereinafter, each layer constituting the piezoelectric element 22 will be described in detail in order. Note that the configuration of each layer of the piezoelectric elements 23 and 24 is the same as that of the piezoelectric element 22, and therefore the description thereof is omitted.
[First electrode layer]
As shown in FIG. 5, the first electrode layer 221 is provided from the base 27 to the vibrating arm 28 along the extending direction (Y-axis direction).

In the present embodiment, the length L 1 of the first electrode layer 221 is shorter than the length L of the vibrating arm 28 on the vibrating arm 28.
Therefore, the end of the first electrode layer 221 opposite to the base 27 (hereinafter also referred to as “the tip of the first electrode layer 221”) is the end of the piezoelectric layer 222 opposite to the base 27 (hereinafter referred to as “the end of the first electrode layer 221”). , Also referred to as “the tip of the piezoelectric layer 222”). Here, the region where the driving force of the piezoelectric element 22 (expansion and contraction due to the piezoelectric effect) is generated is a region where the first electrode layer 221, the piezoelectric layer 222, and the second electrode layer 223 overlap in plan view. Almost matches. On the other hand, a region where the first electrode layer 221 and the second electrode layer 223 overlap in plan view has a capacity as a plate capacitor. If this is formed over the resonating arm 28, the electric parallel capacitance of the resonator element 2 increases, which affects vibration characteristics (particularly, Q value and phase difference). The driving force of the piezoelectric element 22 is transmitted to a partial range in the extending direction of the first vibrating arm 28 by positioning the tip closer to the base 27 side than the tip of the piezoelectric layer 222 as in the present invention. However, the electric parallel capacity of the vibrating arm 28 can be reduced.

  In particular, the tip of the first electrode layer 221 is located near the center in the extending direction of the vibrating arm 28. Thus, the vibrating arm 28 can be efficiently vibrated by the piezoelectric element 22 by applying the driving force of the piezoelectric element 22 to the proximal end portion of the vibrating arm 28. On the other hand, since the piezoelectric layer 222 is formed on the entire vibrating arm 28, the rigidity of the vibrating arm 28 is constant throughout. Therefore, it is possible to prevent an unnecessary vibration mode from being generated in the vibrating arm 28.

  The first electrode layer 221 is provided over substantially the entire area of the vibrating arm 28 in the X-axis direction. The length (that is, the width) of the first electrode layer 221 in the X-axis direction is set equal to or slightly shorter than the length (that is, the width) of the vibrating arm 28 in the X-axis direction. The present invention is not limited to the positional relationship between the length of the first electrode layer 221 and the length of the second electrode layer 223. Either one may be longer or shorter, but the overlapping portion in plan view is important.

  Such a first electrode layer 221 includes gold (Au), gold alloy, platinum (Pt), aluminum (Al), aluminum alloy, silver (Ag), silver alloy, chromium (Cr), chromium alloy, copper ( Cu), molybdenum (Mo), niobium (Nb), tungsten (W), iron (Fe), titanium (Ti), cobalt (Co), zinc (Zn), zirconium (Zr), and other metal materials, and at least It can be formed of an alloy material containing one or more of these metals.

Among them, as a constituent material of the first electrode layer 221, it is preferable to use a metal (gold, gold alloy) or platinum mainly made of gold, and a metal (especially gold) mainly made of gold. More preferred.
Au is suitable as an electrode material because it has excellent conductivity (low electrical resistance) and excellent resistance to oxidation. Further, Au can be easily patterned by etching as compared with Pt. Furthermore, the orientation of the piezoelectric layer 222 can be improved by forming the first electrode layer 221 with gold or a gold alloy.

  The average thickness of the first electrode layer 221 is not particularly limited, but is preferably about 1 to 300 nm, and more preferably 10 to 200 nm, for example. In particular, it is very important for the formation of the piezoelectric layer 222 to ensure the conductivity of the first electrode layer 221 and to align the crystal surface of the outermost surface of the electrode layer. This is because the orientation of the piezoelectric layer is greatly affected by the interface with the metal layer immediately below. Therefore, the film forming conditions and thickness of the first electrode layer 221 and the electrode patterning process should be performed with great care.

For example, when the first electrode layer 221 is made of gold and the vibration substrate 21 is made of quartz, their adhesion is low. Therefore, in such a case, it is preferable to provide an underlayer made of Ti, Cr, or the like between the first electrode layer 221 and the vibration substrate 21. Thereby, the adhesion between the underlayer and the vibrating arm 28 and the adhesion between the underlayer and the first electrode layer 221 can be made excellent. As a result, the first electrode layer 221 can be prevented from peeling from the vibrating arm, and the reliability of the vibrating piece 2 can be improved.
The average thickness of the underlayer can exert the effect of improving the adhesion as described above while preventing the underlayer from adversely affecting the driving characteristics of the piezoelectric element 22 and the vibration characteristics of the vibrating arm 28. Although it will not specifically limit if possible, For example, it is preferable that it is about 1-300 nm.

[Piezoelectric layer]
As shown in FIG. 5, the piezoelectric layer 222 is provided on the first electrode layer 221 along the extending direction (Y-axis direction) of the vibrating arm 28.
In particular, the piezoelectric layer 222 is provided from the base 27 side to the vicinity of the tip of the vibrating arm 28.
As a result, it is possible to prevent a portion where the rigidity changes suddenly in the middle of the extending direction (longitudinal direction) of the vibrating arm 28. Therefore, it is possible to prevent generation of unnecessary vibration modes of the resonator element 2 and increase the Q value of the resonator element 2. As a result, the oscillation characteristics of the resonator element 2 can be improved.

In particular, the piezoelectric layer 222 is provided over the entire region in the extending direction of the vibrating arm 28. In other words, in the present embodiment, the length L 3 of the piezoelectric layer 222 is equal to the length L of the vibrating arm 28 on the vibrating arm 28. Thereby, the bending rigidity of the vibrating arm 28 can be made uniform.
Further, the piezoelectric layer 222 is provided over the entire surface of one plate surface (main surface) of the vibrating arm 28. That is, it is provided over the entire area in the X-axis direction and the Y-axis direction of one main surface of the vibrating arm 28. Thereby, the bending rigidity of the vibrating arm 28 can be made uniform easily and reliably.

Further, the end portion on the base portion 27 side of the piezoelectric layer 222 (that is, the base end portion of the piezoelectric layer 222) is provided so as to straddle the boundary portion between the vibrating arm 28 and the base portion 27.
Thereby, the driving force of the piezoelectric element 22 can be efficiently transmitted to the vibrating arm 28. In addition, a sudden change in rigidity at the boundary between the vibrating arm 28 and the base 27 can be mitigated. Therefore, the Q value of the resonator element 2 can be increased.

Examples of the constituent material (piezoelectric material) of the piezoelectric layer 222 include zinc oxide (ZnO), aluminum nitride (AlN), lithium tantalate (LiTaO ₃ ), lithium niobate (LiNbO ₃ ), and niobic acid. Potassium (KNbO ₃ ), lithium tetraborate (Li ₂ B ₄ O ₇ ), barium titanate (BaTiO ₃ ), PZT (lead zirconate titanate) and the like can be mentioned, but it is preferable to use AIN or ZnO.

  Among these, it is preferable to use ZnO or AlN as the constituent material of the piezoelectric layer 222. ZnO (zinc oxide) and aluminum nitride (AlN) are excellent in self-orientation in the film formation process. Therefore, the CI value of the resonator element 2 can be reduced by using the piezoelectric layer 222 made of ZnO as a main material. Moreover, these materials can be formed into a film by the reactive sputtering method.

Further, when the elastic constant of the material constituting the piezoelectric layer 222 is larger than the elastic constant of the material constituting the vibrating substrate 21 (that is, the material constituting the vibrating arm 28), the piezoelectric layer 222 has the vibrating arm 28. The effect on the vibration characteristics is large. Therefore, the effect becomes remarkable by applying the present invention in such a case.
For example, the elastic constant of quartz is C11 = 0.86 × 10 ¹¹ [N / m ² ], whereas the elastic constant of ZnO is C11 = 2.1 × 10 ¹¹ [N / m ² ] (quartz The elastic constant of AlN is C11 = 3.45 × 10 ¹¹ [N / m ² ] (about 4 times that of quartz).

  The average thickness of the piezoelectric layer 222 is preferably 50 to 3000 [nm], and more preferably 200 to 2000 [nm]. This is because if the piezoelectric layer is too thin, the crystal orientation is not sufficient and the piezoelectric effect is hardly exhibited. On the other hand, if the piezoelectric layer is too thick, it is difficult to perform patterning, which sometimes leads to a decrease in process yield such as disconnection failure. Therefore, by selecting an appropriate thickness, the driving characteristics of the piezoelectric element 22 can be made excellent.

[Second electrode layer]
As shown in FIG. 5, the second electrode layer 223 is provided on the piezoelectric layer 222 along the extending direction (Y-axis direction) of the vibrating arm 28.
In the present embodiment, the length L 2 of the second electrode layer 223 is shorter than the length L of the vibrating arm 28 on the vibrating arm 28. Further, on the vibrating arm 28, the length L <b> 2 of the second electrode layer 223 is equal to the length L <b> 1 of the first electrode layer 221.

  The second electrode layer 223 includes gold (Au), gold alloy, platinum (Pt), aluminum (Al), aluminum alloy, silver (Ag), silver alloy, chromium (Cr), chromium alloy, copper ( Cu), molybdenum (Mo), niobium (Nb), tungsten (W), iron (Fe), titanium (Ti), cobalt (Co), zinc (Zn), zirconium (Zr), and other metal materials, and at least It can be formed of an alloy material containing one or more of these metals. In particular, as the constituent material of the second electrode layer 223, it is preferable to use gold (gold, gold alloy) or platinum, which is the main material of gold, as in the case of the first electrode layer 221, and metal which is mainly composed of gold. It is more preferable to use (especially gold).

  The average thickness of the second electrode layer 223 is not particularly limited, but is preferably about 1 to 300 nm, and more preferably 10 to 200 nm, for example. The thickness of the second electrode layer 223 should be optimized in view of process defects such as disconnection and etching residue while ensuring conductivity. Thereby, the vibration characteristic of the piezoelectric element 22 can be made excellent.

Note that an insulating layer such as SiO ₂ (silicon oxide) or AlN (aluminum nitride) may be provided between the piezoelectric layer 222 and the second electrode layer 223 as necessary. This insulator layer has a function of protecting the piezoelectric layer 222 and preventing a short circuit between the first electrode layer 221 and the second electrode layer 223. The insulator layer may be formed so as to cover only the upper surface of the piezoelectric layer 222, or the upper surface of the piezoelectric layer 222 and the side surface of the piezoelectric layer 222 (other than the surface in contact with the first electrode layer 221). May also be formed so as to cover the surface.
The average thickness of the insulator layer is not particularly limited, but is preferably 50 to 500 nm. When the thickness is less than the lower limit value, the effect of preventing the short circuit as described above tends to be reduced. On the other hand, when the thickness exceeds the upper limit value, effective voltage application cannot be performed. 22 may be adversely affected.

In the piezoelectric element 22 configured as described above, when a voltage is applied between the first electrode layer 221 and the second electrode layer 223, an electric field in the Z-axis direction is applied to the piezoelectric layer 222. Arise. Due to this electric field, the piezoelectric layer 222 expands or contracts in the Z-axis direction, causing the vibrating arm 28 to bend and vibrate in the Z-axis direction.
Similarly, in the piezoelectric element 23, when a voltage is applied between the first electrode layer 231 and the second electrode layer 233, the piezoelectric layer 232 expands or contracts in the Z-axis direction and vibrates. The arm 29 is bent and vibrated in the Z-axis direction. In the piezoelectric element 24, when a voltage is applied between the first electrode layer 241 and the second electrode layer 243, the piezoelectric layer 242 expands or contracts in the Z-axis direction, and the vibrating arm 30 is bent and vibrated in the Z-axis direction.

  In the piezoelectric elements 22, 23, and 24, the first electrode layers 221 and 232 described above are electrically connected to the second electrode layer 243 through a conduction portion that is not illustrated and includes a through electrode and a wiring. Has been. The second electrode layer 243 is electrically connected to a connection electrode 41 provided on the upper surface of the base portion 27 as shown in FIG. Thus, the first electrode layers 221 and 232 and the second electrode layer 243 are electrically connected to the connection electrode 41, respectively.

  In addition, the first electrode layer 241 is electrically connected to the second electrode layers 223 and 235 through a conduction portion made up of a through electrode and a wiring (not shown). The second electrode layers 223 and 235 are electrically connected to the connection electrode 42 provided on the lower surface of the base portion 27 via the wiring 43 as shown in FIG. Accordingly, the first electrode layer 241 and the second electrode layers 223 and 235 are electrically connected to the connection electrode 42.

  The connection electrodes 41 and 42 and the wiring 43 are gold (Au), gold alloy, platinum (Pt), aluminum (Al), aluminum alloy, silver (Ag), silver alloy, chromium (Cr), chromium alloy, Metal materials such as copper (Cu), molybdenum (Mo), niobium (Nb), tungsten (W), iron (Fe), titanium (Ti), cobalt (Co), zinc (Zn), zirconium (Zr), Further, it can be formed of an alloy material containing at least one of these metals. Further, these can be formed simultaneously with the first electrode layers 221, 232, 242 or the second electrode layers 223, 235, 245.

In the resonator element 2 having such a configuration, when a voltage (voltage for vibrating the vibrating arms 28, 29, 30) is applied between the connection electrode 41 and the connection electrode 42, the first electrode layer 221 and 231 and the second electrode layer 243, and the first electrode layer 241 and the second electrode layer 223 and 233 have opposite polarities, and the piezoelectric layers 222, 232, and 242 described above have Z An axial voltage is applied. Thereby, the vibrating arms 28, 29, and 30 can be flexibly vibrated at a certain frequency (resonance frequency) by the inverse piezoelectric effect of the piezoelectric material. At this time, as shown in FIG. 6, the vibrating arms 28 and 29 bend and vibrate in the same direction, and the vibrating arm 30 bends and vibrates in the direction opposite to the vibrating arms 28 and 29.
In this way, by causing the two adjacent vibrating arms to bend and vibrate in directions opposite to each other, leakage vibration caused by the two adjacent vibrating arms 28, 30 and 29, 30 can be minimized. As a result, vibration leakage can be prevented.

  In such a vibrating piece 2, as described above, the piezoelectric layer 222 is provided from the base 27 side to the vicinity of the tip of the vibrating arm 28, and therefore, as shown in FIGS. 7A and 8A. As described above, it is possible to prevent a portion where the rigidity changes abruptly in the middle of the extending direction (longitudinal direction) of the vibrating arm 28. Similarly, it is possible to prevent formation of a portion where the stiffness suddenly changes in the extending direction (longitudinal direction) of the vibrating arms 29 and 30.

  On the other hand, for example, as shown in FIGS. 7B and 8B, a piezoelectric element 122 having a piezoelectric layer 1221 having a shorter length than the vibrating arm 28 is provided on the vibrating arm 28. In the resonator element 102, the rigidity is different between the proximal end portion (the portion covered with the piezoelectric layer 1221) and the distal end portion (the portion not covered with the piezoelectric layer 1221) of the vibrating arm 28. The vibrating arm vibrates in the vicinity of the tip of the piezoelectric film so as to be bent. When there is a large difference between the elastic constant of the vibrating arm and the elastic constant of the piezoelectric layer as in this embodiment, the vibration mode in which the vibrating arm is bent becomes significant. Therefore, an unnecessary vibration mode is generated. In such a bent portion of the vibrating arm 28 of the vibrating piece 2, a temperature rise occurs according to the linear expansion coefficient of the material. Therefore, in the resonator element 102, the internal loss increases and the Q value cannot be sufficiently increased.

(Manufacturing method of vibrating piece)
Here, an example of a method for manufacturing the above-described resonator element 2 will be briefly described.
The above-described method for manufacturing the resonator element 2 includes: [A] the step of forming the first electrode layers 221, 231 and 241 on the vibrating arms 28, 29 and 30, and [B] the first electrode layers 221, 231 and 241; And forming a second electrode layer 223, 233, 343 on the piezoelectric layer 222, 232, 242 and [C] the piezoelectric layer 222, 232, 242.

Hereafter, each process is demonstrated easily.
[A]
First, a substrate for forming the vibration substrate 21 is prepared.
Then, the vibration substrate 21 is formed by etching the substrate.
More specifically, for example, when the substrate is a quartz substrate, the thin-walled portion 271 of the quartz substrate is removed by anisotropic etching using BHF (buffered hydrogen fluoride) as an etchant. Turn into. Thereafter, the thinned portion is partially removed by anisotropic etching similar to the above to form the vibrating arms 28, 29, and 30. Thereby, the vibration substrate 21 is formed.
Thereafter, first electrode layers 221, 231, and 241 are formed on the vibrating arms 28, 29, and 30. At that time, patterning is performed as necessary, and wiring is simultaneously formed.

The first electrode layers 221, 231, and 241 can be formed by physical vapor deposition such as sputtering or vacuum deposition, chemical vapor deposition called CVD (Chemical Vapor Deposition), ink jet, or the like. In this case, it is preferable to use a physical vapor deposition method (particularly, a sputtering method). In forming the first electrode layers 221, 231 and 241, it is preferable to use a photolithography method.
Note that the first electrode layers 221, 231 and 241 can be collectively formed in the same film formation step.

[B]
Next, piezoelectric layers 222, 232, and 242 are formed on the first electrode layers 221, 231, and 241.
The piezoelectric layers 222, 232, and 242 are formed by a physical vapor deposition method such as sputtering or vacuum deposition, a vapor deposition method called CVD (Chemical Vapor Deposition), or dip coating. Here, it is preferable to use a physical vapor deposition method (particularly reactive sputtering method). In forming (patterning) the piezoelectric layers 222, 232, and 242, it is preferable to use a photolithography method. Further, when patterning the piezoelectric layers 222, 232, and 242 it is preferable to use wet etching to remove unnecessary portions.
Note that the piezoelectric layers 222, 232, and 242 can be collectively formed in the same film forming process.

[C]
Next, second electrode layers 223, 233 and 343 are formed on the piezoelectric layers 222, 232 and 242. At that time, the connection electrodes 41 and 42 are also formed at the same time.
The formation of the second electrode layers 223, 233, and 343 can be performed in the same manner as the first electrode layers 221, 231, and 241 described above.
As described above, the resonator element 2 can be manufactured.

(package)
Next, the package 3 that houses and fixes the resonator element 2 will be described.
As illustrated in FIG. 1, the package 3 includes a plate-like base substrate 31, a frame-like frame member 32, and a plate-like lid member 33. The base substrate 31, the frame member 32, and the lid member 33 are laminated in this order from the lower side to the upper side. The base substrate 31 and the frame member 32 are formed of a ceramic material or the like which will be described later, and are joined by being integrally fired. The frame member 32 and the lid member 33 are joined by an adhesive or a brazing material. The package 3 houses the resonator element 2 in an internal space S defined by the base substrate 31, the frame member 32, and the lid member 33. In addition to the vibrating piece 2, an electronic component that drives the vibrating piece 2 and the like can be housed in the package 3.

As the constituent material of the base substrate 31, those having insulating properties (non-conductive) are preferable. For example, various glass materials, various ceramic materials such as oxide ceramics, nitride ceramics, carbide ceramics, polyimide, etc. Various resin materials can be used.
In addition, as the constituent material of the frame member 32 and the lid member 33, for example, the same constituent material as that of the base substrate 31, various metal materials such as Al and Cu, various glass materials, and the like can be used. In particular, when a material having light transmissivity such as a glass material is used as a constituent material of the lid member 33, if a metal covering portion (not shown) is formed on the vibrating piece 2 in advance, the vibrating piece 2 is packaged. Even after being housed in 3, by irradiating the metal coating part with a laser through the lid member 33, the metal coating part is removed to reduce the mass of the resonator element 2 (by a mass reduction method). ), The frequency of the resonator element 2 can be adjusted.

On the upper surface of the base substrate 31, the above-described vibrating piece 2 is fixed via a fixing material 5. The fixing material 5 is made of, for example, an epoxy, polyimide, or silicone adhesive. In such a fixing material 5, an uncured (unsolidified) adhesive is applied onto the base substrate 31, and the vibration piece 2 is placed on the adhesive, and then the adhesive is cured or solidified. Is formed. Thereby, the resonator element 2 (base portion 27) is securely fixed to the base substrate 31.
In addition, you may perform this fixation using electrically conductive adhesives, such as an epoxy type, a polyimide type, and a silicone type containing electroconductive particle.

In addition, a pair of electrodes 35 a and 35 b are formed on the upper surface of the base substrate 31 so as to be exposed to the internal space S.
The electrode 35a is electrically connected to the connection electrode 42 described above via, for example, a metal wire (bonding wire) 38 formed by a wire bonding technique. The electrode 35b is electrically connected to the connection electrode 41 described above via a metal wire (bonding wire) 37 formed by, for example, a wire bonding technique.
In addition, the connection method of a pair of electrode 35a, 35b and the connection electrodes 41 and 42 is not limited to this, For example, you may carry out with a conductive adhesive. In this case, for example, the front and back of the vibrating piece 2 may be reversed, or the connection electrodes 41 and 42 may be formed on the lower surface of the vibrating piece 2.

Further, four external terminals 34 a, 34 b, 34 c, 34 d are provided on the lower surface of the base substrate 31.
Out of these four external terminals 34a to 34d, the external terminals 34a and 34b are electrically connected to the electrodes 35a and 35b through conductor posts (not shown) provided in via holes formed in the base substrate 31, respectively. It is a connected hot terminal. The other two external terminals 34c and 34d are used to increase the bonding strength and equalize the distance between the package 3 and the mounting board when the package 3 is mounted on the mounting board, respectively. This is a dummy terminal.

Such electrodes 35a and 35b and external terminals 34a to 34d can be formed, for example, by applying gold plating to an underlying layer of tungsten and nickel plating.
When an electronic component is housed inside the package 3, the lower surface of the base substrate 31 can be used to check the characteristics of the electronic component and various information in the electronic component (for example, temperature compensation information of the vibration device) as necessary. A write terminal for rewriting (adjustment) may be formed.

According to the first embodiment as described above, since the piezoelectric layers 222, 232, and 242 are provided from the base 27 side to the vicinity of the tips of the vibrating arms 28, 29, and 30, the vibrating arms 28 and 29 are provided. , 30 in the middle of the extending direction (longitudinal direction) can be prevented from forming a portion where the rigidity changes abruptly. Therefore, it is possible to prevent generation of unnecessary vibration modes of the resonator element 2 and increase the Q value of the resonator element 2. As a result, the oscillation characteristics of the resonator element 2 can be improved.
In addition, the vibration device 1 in which such a resonator element 2 is housed in the package 3 has excellent oscillation characteristics.

<Second Embodiment>
Next, a second embodiment of the vibration device of the present invention will be described.
9 is a top view showing a vibrating device according to the second embodiment of the present invention, and FIG. 10 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG.
Hereinafter, the vibration device according to the second embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.
The vibration device of the second embodiment is substantially the same as the first embodiment except that the length of the first electrode layer is different. 9 and 10, the same reference numerals are given to the same configurations as those in the above-described embodiment.

As shown in FIG. 9, the vibrating device 1 </ b> A of the present embodiment includes a vibrating piece 2 </ b> A and a package 3 that stores the vibrating piece 2 </ b> A.
The resonator element 2 </ b> A includes a piezoelectric element 22 </ b> A provided on the vibrating arm 28, a piezoelectric element 23 </ b> A provided on the vibrating arm 29, and a piezoelectric element 24 </ b> A provided on the vibrating arm 30.
Hereinafter, the piezoelectric element 22A will be described. The piezoelectric elements 23A and 24A are the same as the piezoelectric element 22A, and thus the description thereof is omitted.

As shown in FIG. 10, the piezoelectric element 22A is configured by laminating a first electrode layer 221A, a piezoelectric layer (piezoelectric thin film) 222, and a second electrode layer 223 on the vibrating arm 28 in this order. ing.
The first electrode layer 221 </ b> A is provided on the vibrating arm 28 from the base 27 along the extending direction (Y-axis direction).

In the present embodiment, on the vibrating arm 28, the length L1 of the first electrode layer 221A is longer than the length L2 of the second electrode layer 223. On the vibrating arm 28, the length L1 of the first electrode layer 221A is substantially equal to the length L of the vibrating arm 28.
Accordingly, the piezoelectric layer 222 can be provided on the first electrode layer 221 </ b> A also on the distal end side of the vibrating arm 28. Therefore, the orientation of the piezoelectric layer 222 can be improved by the surface state of the first electrode layer 221 over substantially the entire region of the vibrating arm 28 in the longitudinal direction. As a result, the vibration characteristics of the vibrating arm 28 can be made uniform over the entire area in the longitudinal direction.
Note that the portion of the first electrode layer 221A that protrudes beyond the tip of the second electrode layer 223 hardly contributes to the application of an electric field to the piezoelectric layer 222.

In the present embodiment, the length L1 of the first electrode layer 221A on the vibrating arm 28 is substantially equal to the length L of the vibrating arm 28, but the tip of the second electrode layer 223 is the tip of the piezoelectric layer 222. Therefore, the driving force of the piezoelectric element 22A can be transmitted to a partial range in the extending direction of the vibrating arm 28.
Further, according to the second embodiment as described above, the same effects as those of the first embodiment described above can be exhibited.

<Third Embodiment>
Next, a third embodiment of the vibration device of the invention will be described.
FIG. 11 is a cross-sectional view showing a vibrating device according to the third embodiment of the present invention, and FIG. 12 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG.
Hereinafter, the vibration device according to the third embodiment will be described focusing on differences from the above-described embodiment, and description of similar matters will be omitted.
The vibration device of the third embodiment is substantially the same as that of the first embodiment except that the length of the second electrode layer is different. 11 and 12, the same reference numerals are given to the same configurations as those in the above-described embodiment.

As shown in FIG. 11, the vibration device 1B according to the present embodiment includes a vibration piece 2B and a package 3 that houses the vibration piece 2B.
The resonator element 2 </ b> B includes a piezoelectric element 22 </ b> B provided on the vibrating arm 28, a piezoelectric element 23 </ b> B provided on the vibrating arm 29, and a piezoelectric element 24 </ b> B provided on the vibrating arm 30.
Hereinafter, the piezoelectric element 22B will be described. Since the piezoelectric elements 23B and 24B are the same as the piezoelectric element 22B, the description thereof is omitted.

As shown in FIG. 12, the piezoelectric element 22B is configured by laminating a first electrode layer 221, a piezoelectric layer (piezoelectric thin film) 222, and a second electrode layer 223B in this order on the vibrating arm 28. ing.
The second electrode layer 223B is provided on the piezoelectric layer 222 along the extending direction of the vibrating arm 28 (Y-axis direction).

In the present embodiment, on the vibrating arm 28, the length L2 of the second electrode layer 223B is longer than the length L1 of the first electrode layer 221. On the vibrating arm 28, the length L2 of the second electrode layer 223B is substantially equal to the length L of the vibrating arm 28.
Such a portion of the second electrode layer 223B that protrudes from the tip of the first electrode layer 221 hardly contributes to the application of the electric field to the piezoelectric layer 222. For example, the resonance frequency of the vibrating arm 28 is adjusted. Can be used. Such adjustment of the resonance frequency can be performed by partially removing the portion by laser light irradiation.
Further, according to the third embodiment as described above, the same effects as those of the first embodiment described above can be exhibited.

<Fourth embodiment>
Next, a fourth embodiment of the vibration device of the invention will be described.
FIG. 13 is a cross-sectional view showing a vibrating device according to the fourth embodiment of the present invention, and FIG. 14 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG.
Hereinafter, the vibration device according to the fourth embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.
The vibration device of the fourth embodiment is substantially the same as the first embodiment except that the thickness of the tip portion of the piezoelectric layer is different. In FIGS. 13 and 14, the same reference numerals are given to the same configurations as those in the above-described embodiment.

As shown in FIG. 13, the vibrating device 1 </ b> C of the present embodiment includes a vibrating piece 2 </ b> C and a package 3 that stores the vibrating piece 2 </ b> C.
The resonator element 2 </ b> C includes a piezoelectric element 22 </ b> C provided on the vibrating arm 28, a piezoelectric element 23 </ b> C provided on the vibrating arm 29, and a piezoelectric element 24 </ b> C provided on the vibrating arm 30.
Hereinafter, the piezoelectric element 22C will be described. The piezoelectric elements 23C and 24C are the same as the piezoelectric element 22C, and thus description thereof is omitted.

As shown in FIG. 14, the piezoelectric element 22C is configured by laminating a first electrode layer 221, a piezoelectric layer (piezoelectric thin film) 222C, and a second electrode layer 223 on the vibrating arm 28 in this order. ing.
The piezoelectric layer 222 </ b> C is provided on the first electrode layer 221 along the extending direction (Y-axis direction) of the vibrating arm 28.

In the present embodiment, the length L 3 of the piezoelectric layer 222 C on the vibrating arm 28 is substantially equal to the length L of the vibrating arm 28.
The thickness of the portion (tip portion) of the piezoelectric layer 222C that protrudes beyond the tips of the first electrode layer 221 and the second electrode layer 223 is from the base end side of the vibrating arm 28 toward the tip side. It is gradually decreasing.

As described above, the thickness of the end portion of the piezoelectric layer 222C opposite to the base portion 27 is gradually reduced from the proximal end side to the distal end side of the vibrating arm 28, whereby the distal end of the piezoelectric layer 222C and the vibrating arm are reduced. Even if the tip of 28 does not coincide, it is possible to prevent the rigidity from changing suddenly in a part of the extending direction of the vibrating arm 28.
Further, according to the fourth embodiment as described above, the same effects as those of the first embodiment described above can be exhibited.

<Fifth Embodiment>
Next, a fifth embodiment of the vibration device of the invention will be described.
FIG. 15 is a cross-sectional view showing a vibrating device according to a fifth embodiment of the present invention, and FIG. 16 is a partial cross-sectional perspective view showing a vibrating arm provided in the vibrating piece shown in FIG.
Hereinafter, the vibration device according to the fifth embodiment will be described focusing on the differences from the above-described embodiment, and description of similar matters will be omitted.
The vibration device of the fifth embodiment is substantially the same as that of the first embodiment except that a piezoelectric layer (piezoelectric element) is also provided on the lower surface side of each vibration arm. In FIGS. 15 and 16, the same components as those in the above-described embodiment are denoted by the same reference numerals.

As shown in FIG. 15, the vibration device 1 </ b> D of the present embodiment includes a vibration piece 2 </ b> D and a package 3 that stores the vibration piece 2 </ b> D.
The resonator element 2 </ b> D includes piezoelectric elements 61, 62, and 63 provided on the lower surface of the vibration substrate 21 in addition to the piezoelectric elements 22, 23, and 24 provided on the upper surface of the vibration substrate 21. .
Specifically, the resonator element 2 </ b> D includes a piezoelectric element 61 provided on the vibrating arm 28, a piezoelectric element 62 provided on the vibrating arm 29, and a piezoelectric element 63 provided on the vibrating arm 30. And have.

As shown in FIG. 16, the piezoelectric element 61 is configured by laminating a first electrode layer 611, a piezoelectric layer (piezoelectric thin film) 612, and a second electrode layer 613 on the vibrating arm 28 in this order. Yes.
Such a piezoelectric element 61 is configured to be symmetric with the piezoelectric element 22 via the vibrating arm 28.
In particular, the piezoelectric layer 612 is provided from the base 27 side to the vicinity of the tip of the vibrating arm 28.
Thereby, it can prevent more effectively that the part where rigidity changes rapidly in the middle of the extending direction (longitudinal direction) of the vibrating arm 28 can be prevented.

  Similarly, the piezoelectric element 62 is configured by laminating a first electrode layer 621, a piezoelectric layer (piezoelectric thin film) 622, and a second electrode layer 623 on the vibrating arm 29 in this order. The piezoelectric element 63 is configured by laminating a first electrode layer 631, a piezoelectric layer (piezoelectric thin film) 632, and a second electrode layer 633 in this order on the vibrating arm 30. Thereby, it can prevent more effectively that the part where rigidity changes rapidly in the middle of the extending direction (longitudinal direction) of the vibrating arms 29 and 30 can be prevented.

In such a vibrating piece 2D, the piezoelectric elements 61, 62, 63 need not be operated, and the piezoelectric elements 61, 62, 63 are operated in synchronization with the driving of the piezoelectric elements 22, 23, 24. You may let them. When the piezoelectric elements 61, 62, 63 are operated in synchronization with the driving of the piezoelectric elements 22, 23, 24, for example, wiring may be appropriately formed on the side surface of the vibrating arm 28 and the base portion 27.
Further, according to the fifth embodiment as described above, the same effects as those of the first embodiment described above can be exhibited.
The vibration device of each embodiment as described above can be applied to various electronic devices, and the obtained electronic device has high reliability.

Here, an electronic apparatus including the vibration device according to the invention will be described in detail with reference to FIGS.
FIG. 17 is a perspective view illustrating a configuration of a mobile (or notebook) personal computer to which an electronic apparatus including the vibration device according to the invention is applied.
In this figure, a personal computer 1100 includes a main body portion 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display portion 100. The display unit 1106 is rotated with respect to the main body portion 1104 via a hinge structure portion. It is supported movably.
Such a personal computer 1100 incorporates the vibration device 1 that functions as a filter, a resonator, a reference clock, and the like.

FIG. 18 is a perspective view illustrating a configuration of a mobile phone (including PHS) to which an electronic apparatus including the vibration device of the invention is applied.
In this figure, a cellular phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204, and a mouthpiece 1206, and the display unit 100 is disposed between the operation buttons 1202 and the earpiece 1204.
Such a cellular phone 1200 incorporates the vibration device 1 that functions as a filter, a resonator, or the like.

FIG. 19 is a perspective view illustrating a configuration of a digital still camera to which an electronic apparatus including the vibration device according to the invention is applied. In this figure, connection with an external device is also simply shown.
Here, an ordinary camera sensitizes a silver halide photographic film with a light image of a subject, whereas a digital still camera 1300 photoelectrically converts a light image of a subject with an imaging device such as a CCD (Charge Coupled Device). An imaging signal (image signal) is generated.

A display unit is provided on the back of a case (body) 1302 in the digital still camera 1300, and is configured to display based on an imaging signal from the CCD. The display unit is a finder that displays an object as an electronic image. Function.
A light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided on the front side (the back side in the drawing) of the case 1302.
When the photographer confirms the subject image displayed on the display unit and presses the shutter button 1306, the CCD image pickup signal at that time is transferred and stored in the memory 1308.

In the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312 and a personal computer 1440 is connected to the input / output terminal 1314 for data communication as necessary. Further, the imaging signal stored in the memory 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation.
Such a digital still camera 1300 incorporates the vibration device 1 that functions as a filter, a resonator, and the like.

  In addition to the personal computer (mobile personal computer) shown in FIG. 17, the mobile phone shown in FIG. 18, and the digital still camera shown in FIG. Inkjet printers), laptop personal computers, televisions, video cameras, video tape recorders, car navigation devices, pagers, electronic notebooks (including those with communication functions), electronic dictionaries, calculators, electronic game devices, word processors, workstations, televisions Telephone, crime prevention TV monitor, electronic binoculars, POS terminal, medical equipment (for example, electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring devices, instruments (E.g., vehicle, aircraft, ship total S), it can be applied to a flight simulator or the like.

  As described above, the resonator element, the vibration device, and the electronic apparatus of the present invention have been described based on the illustrated embodiment. However, the present invention is not limited to this, and the configuration of each unit may be any arbitrary function having the same function. It can be replaced with that of the configuration. In addition, any other component may be added to the present invention. Further, the present invention may be a combination of any two or more configurations (features) of the above embodiments.

For example, in the embodiment described above, the case where the resonator element has three vibrating arms has been described as an example. However, the number of vibrating arms may be one or two, or may be four or more. Good.
In addition, the vibration device of the present invention can be applied to a gyro sensor or the like in addition to a piezoelectric oscillator such as a crystal oscillator (SPXO), a voltage controlled crystal oscillator (VCXO), a temperature compensated crystal oscillator (TCXO), a crystal oscillator with a thermostat (OCXO). Applied.

  DESCRIPTION OF SYMBOLS 1 ... Vibration device 1A ... Vibration device 1B ... Vibration device 1C ... Vibration device 1D ... Vibration device 2 ... Vibration piece 2A ... Vibration piece 2B ... Vibration piece 2C ... Vibration piece 2D ... Vibration piece 3 ... Package 5 ... Fixing material 21 ... Vibrating substrate 22 ... Piezoelectric element 22A ... Piezoelectric element 22B ... Piezoelectric element 22C ... Piezoelectric element 23 ... Piezoelectric element 23A ... Piezoelectric element 23B ... Piezoelectric element 23C ... Piezoelectric element 24 ... Piezoelectric element 24A ... Piezoelectric element 24B ... Piezoelectric element 24C ... Piezoelectric element 27 ... Base 28 ... Vibration arm 29 ... Vibration arm 30 ... Vibration arm 31 ... Base substrate 32 ... Frame member 33 ... Lid member 34a ... External terminal 34b ... External terminal 34c ... External terminal 34d ... External terminal 3 a ... Electrode 35b ... Electrode 37 ... Metal wire 38 ... Metal wire 41 ... Connection electrode 42 ... Connection electrode 43 ... Wiring 61 ... Piezoelectric element 62 ... Piezoelectric element 63 ... Piezoelectric element DESCRIPTION OF SYMBOLS 102 ... Vibrating piece 122 ... Piezoelectric element 221 ... 1st electrode layer 221A ... 1st electrode layer 222 ... Piezoelectric body layer 222C ... Piezoelectric body layer 223 ... 2nd electrode layer 223A ... Second electrode layer 223B ... Second electrode layer 231 ... First electrode layer 232 ... Piezoelectric layer 232C ... Piezoelectric layer 233 ... Second electrode layer 233A ... Second electrode layer 233B Second electrode layer 241 First electrode layer 242 Piezoelectric layer 242C Piezoelectric layer 243 Second electrode layer 243A Second electrode layer 243B Second electrode Layer 271, thin Thick part 272 ... Thick part 611 ... First electrode layer 612 ... Piezoelectric layer 613 ... Second electrode layer 621 ... First electrode layer 622 ... Piezoelectric layer 623 ... Second Electrode layer 631 ··· First electrode layer 632 · · · Piezoelectric layer 633 · · · Second electrode layer 1221 · · · Piezoelectric layer 100 · · · Display unit 1100 · · · Personal computer 1102 · · · Keyboard 1104 · · · Body portion 1106 Display unit 1200 Mobile phone 1202 Operation button 1204 Earpiece 1206 Transmission mouth 1300 Digital still camera 1302 Case 1304 Light receiving unit 1306 Shutter button 1308 Memory 1312 Video signal output terminal 1314 Input / output terminal for data communication 1430 TV monitor 1440 ‥‥ personal computer L1 ‥‥ length L2 ‥‥ length L3 ‥‥ length S ‥‥ interior space

Claims (10)

The base,
At least one plate-like vibrating arm extending from the base;
First electrode layer on the vibrating arm, the second electrode layer, and the piezoelectric layer between the first electrode layer and the second electrode layer is the product layer, said first electrode layer by applying a voltage between the second electrode layer, by stretching the piezoelectric layer, anda piezoelectric element to bending vibration of the vibrating arm,
In plan view, the piezoelectric layer extends from the base portion to the tip of the vibrating arm, covers the entire area in the extending direction of the vibrating arm, and further covers the entire surface of one plate of the vibrating arm. A vibrating piece characterized by being provided . The end of at least one of the first electrode layer and the second electrode layer opposite to the base is closer to the base than the end of the piezoelectric layer opposite to the base. The resonator element according to claim 1, wherein The end of at least one of the first electrode layer and the second electrode layer opposite to the base is located at the center in the extending direction of the vibrating arm. The resonator element according to the item. The piezoelectric layer, the vibration element according to any one of claims 1 to 3 is provided to on the base. The thickness of the end of the piezoelectric layer opposite to the base is from the base end of the vibrating arm.
The resonator element according to any one of claims 1 to 4 , wherein the resonator element is gradually reduced toward the tip side. The elastic constant of the material forming the piezoelectric layer, the vibration element according to any one of 5 claims 1 greater than the elastic constant of the material constituting the vibrating arm. A plurality of the vibrating arms are provided side by side in a direction orthogonal to the extending direction of the vibrating arm and the vibration direction of the bending vibration of the vibrating arm by the piezoelectric element, and two adjacent vibrating arms are opposite to each other. resonator element according to any one of claims 1 to bending vibration in the direction 6. The vibrating arm, the vibrating element according to any one of claims 1 to 7 is composed of quartz. A resonator element according to any one of claims 1 to 8 ,
And a package for housing the resonator element. An electronic apparatus comprising the vibration device according to claim 9 .

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