JP2013062643A - Vibration piece, vibrator, oscillator, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inhibit the deterioration of a Q value of a vibration piece, and to provide a vibrator, an oscillator, and an electronic apparatus which include a vibration piece where the deterioration of the Q value is inhibited.SOLUTION: A crystal vibration piece 1 includes: a base part 10; vibration arms 11a, 11b, 11c; and excitation electrodes 12a, 12b, 12c which are provided at the vibration arms 11a, 11b, 11c. The excitation electrodes 12a, 12b, 12c have: first electrodes 12a1, 12b1, 12c1 provided at the main surface 10a side of the vibration arms 11a, 11b, 11c; second electrodes 12a2, 12b2, 12c2 which are provided facing the first electrodes 12a1, 12b1, 12c1; and a piezoelectric material 13 extending between the first electrodes 12a1, 12b1, 12c1 and the second electrodes 12a2, 12b2, 12c2. Indium Tin Oxide is used at least either one of the first electrodes 12a1, 12b1, 12c1 and the second electrodes 12a2, 12b2, 12c2.

Description

  The present invention relates to a resonator element, a vibrator, an oscillator, and an electronic device including the resonator element.

  Conventionally, as a vibrating piece, a pair of electrodes including a base portion and an arm portion extending from the base portion and an excitation portion supported by a first section in the length direction of the arm portion, the excitation portion sandwiching the piezoelectric film and the piezoelectric film A piezoelectric vibrating piece (hereinafter referred to as a vibrating piece) having a film is known (for example, see Patent Document 1).

JP 2009-239860 A

The resonator element of Patent Document 1 has a configuration in which an arm portion (hereinafter referred to as a vibrating arm) is flexibly vibrated in a thickness direction by expansion and contraction of a piezoelectric film of an excitation portion (hereinafter referred to as an excitation electrode).
The Q value of the resonator element as described above (a dimensionless number representing the state of vibration, meaning that the larger this value is, the more stable the vibration is). Reduced by providing.
For the excitation electrode of the vibrating piece as described above, a Ti (titanium) / Au (gold) film (a film in which Ti is laminated on the base layer and Au is laminated on the upper layer) is often used as a pair of electrode films sandwiching the piezoelectric film. ing.
However, according to the analysis by the inventors, there is a problem that the degree of decrease in the Q value is large in the configuration using Ti / Au for the pair of electrode films of the excitation electrode.

  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.

  Application Example 1 A vibrating piece according to this application example includes a base including a base, a vibrating arm extending from the base, a first electrode provided on the vibrating arm, and the first. A second electrode provided above the electrode; and a piezoelectric body disposed between the first electrode and the second electrode, wherein at least one of the first electrode and the second electrode This material is characterized by using ITO.

According to this, the resonator element includes ITO (Indium Tin Oxide) containing several percent tin oxide in indium oxide on at least one of the first electrode and the second electrode (corresponding to a pair of electrode films) provided on the vibrating arm. Since the added compound) is used, a decrease in the Q value is suppressed by the properties of ITO, and the Q value can be improved as compared with the conventional technique using Ti / Au.
This relies on the knowledge obtained by the inventors from the results of analysis by experiments.

  Application Example 2 In the resonator element according to the application example described above, it is preferable that an insulator is provided between the first electrode and the piezoelectric body.

According to this, since the resonator element includes the insulator between the first electrode and the piezoelectric body (corresponding to the piezoelectric film), the insulator improves the orientation of the piezoelectric body during polarization, for example. And the fall of Q value is suppressed more, and Q value can be improved greatly with respect to the prior art which uses Ti / Au.
Note that the insulator is preferably in an amorphous state.

Application Example 3 In the resonator element according to Application Example 2, it is preferable that SiO ₂ is used as a material for the insulator.

According to this, the resonator element, since it is used SiO ₂ (silicon dioxide) on the insulator, the SiO _2, for example, such as by improving the orientation property during polarization of the piezoelectric element, decrease in the Q value This is further suppressed, and the Q value can be dramatically improved as compared with the conventional technique using Ti / Au.

  Application Example 4 In the resonator element according to the application example described above, it is preferable that ZnO is used as the material of the piezoelectric body.

  According to this, since the resonator element uses ZnO (zinc oxide) for the piezoelectric body, it is excellent in stretchability when an electric field is applied due to its high orientation, and can efficiently flex and vibrate the substrate. Can do.

  Application Example 5 In the resonator element according to the application example described above, it is preferable that quartz is used as the material of the base material.

  According to this, since the resonator element uses quartz as the base material, it has excellent workability due to its characteristics, and can stably vibrate regardless of the ambient temperature change.

  Application Example 6 In the resonator element according to the application example, it is preferable that silicon is used as a material for the base material.

  According to this, since the resonator element uses silicon for the base material, it is possible to make the potential performance related to the Q value (for example, the Q value of the base material alone) higher than that of quartz due to its characteristics. .

  Application Example 7 A vibrator according to this application example includes the resonator element according to any one of the application examples described above and a package containing the resonator element.

  According to this, since the vibrator includes the resonator element according to any one of the application examples described above and the package that accommodates the resonator element, the effect according to any one of the application examples can be achieved. A vibrator can be provided.

  Application Example 8 An oscillator according to this application example includes the resonator element according to any one of the application examples described above and an oscillation circuit that oscillates the resonator element.

  According to this, since the oscillator includes the resonator element according to any one of the above application examples and the oscillation circuit that oscillates the resonator element, the oscillator having the effect according to any one of the above application examples is provided. Can be provided.

  Application Example 9 An electronic apparatus according to this application example includes the resonator element according to any one of the application examples described above.

  According to this, since the electronic device includes the resonator element according to any one of the application examples, it is possible to provide an electronic device having the effects described in any of the application examples.

It is a schematic diagram which shows schematic structure of the quartz crystal vibrating piece of 1st Embodiment, (a) is a top view, (b) is sectional drawing in the AA of (a). Sectional drawing in the BB line of Fig.1 (a), and the wiring diagram of each excitation electrode. The figure which showed the relationship between the material of each component of the excitation electrode in a quartz-crystal vibrating piece, and Q value. It is a schematic diagram which shows schematic structure of the crystal oscillator of 2nd Embodiment, (a) is a top view which looked down from the lid (lid body) side, (b) is sectional drawing in CC line of (a). . It is a schematic diagram which shows schematic structure of the crystal oscillator of 3rd Embodiment, (a) is the top view seen from the lid side, (b) is sectional drawing in CC line of (a). The model perspective view which shows the mobile telephone of 4th Embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings.

(First embodiment)
Here, a quartz crystal vibrating piece using quartz as a base material will be described as an example of the vibrating piece.
FIG. 1 is a schematic diagram illustrating a schematic configuration of the quartz crystal resonator element according to the first embodiment. FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view taken along line AA in FIG. In addition, each wiring is abbreviate | omitted and the dimension ratio of each component differs from actual.
FIG. 2 is a cross-sectional view taken along line BB in FIG. 1A and a wiring diagram of each excitation electrode.

As shown in FIG. 1, the quartz crystal resonator element 1 includes a base 10 and three vibrating arms 11 a, 11 b, 11 c extending from the base 10 in the Y-axis direction of the crystal crystal axis as a base material. . In this embodiment, a Z-plate quartz substrate is used for the three vibrating arms 11 a, 11 b, 11 c and the base 10.
The vibrating arms 11a, 11b, and 11c are formed in a substantially prismatic shape, arranged in the X-axis direction of the crystal crystal axis orthogonal to the Y-axis direction in plan view, and specified by the Y-axis direction and the X-axis direction. Excitation electrodes 12a, 12b, and 12c are provided on at least one of main surfaces 10a and 10b (here, main surface 10a) along a plane (XY plane).
The vibrating arms 11a, 11b, and 11c are bent (in an out-of-plane vibration: main) by the excitation electrodes 12a, 12b, and 12c in the Z-axis direction (the arrow direction in FIG. 1B) of the crystal axis perpendicular to the main surface 10a. Vibration in a direction not along the surface 10a).

  Excitation electrodes 12a, 12b, and 12c include first electrodes 12a1, 12b1, and 12c1 provided on the main surface 10a side, and second electrodes 12a2, 12b2, and 12c2 provided above the first electrodes 12a1, 12b1, and 12c1, respectively. The piezoelectric body 13 disposed between the first electrodes 12a1, 12b1, 12c1 and the second electrodes 12a2, 12b2, 12c2, and the insulation disposed between the first electrodes 12a1, 12b1, 12c1 and the piezoelectric body 13. And a laminated structure including the body 14.

A film containing ITO is used for the first electrodes 12a1, 12b1, 12c1 and the second electrodes 12a2, 12b2, 12c2 of the excitation electrodes 12a, 12b, 12c, and the piezoelectric material 13 is compared with ZnO. In particular, a piezoelectric material film having high piezoelectricity (high orientation) is used. The insulator 14 is a film containing SiO _{2 in} an amorphous state.
The first electrode 12a1, 12b1, 12c1 and the second electrode 12a2, 12b2, 12c2 are made of a film containing ITO on one side and another material (for example, Ti / Au, Cr (chrome) on the other side. ) / Au etc.) may also be used.
The piezoelectric material 13 may be a piezoelectric material containing AlN (aluminum nitride) having a crystal structure similar to that of ZnO.

  The excitation electrodes 12a, 12b, and 12c extend from the root portions (boundary portions with the base portion 10) of the vibrating arms 11a, 11b, and 11c toward the distal end, and the full lengths (Y-axis direction) of the vibrating arms 11a, 11b, and 11c. It is preferable that the length is about half of the length from the base to the tip.

As shown in FIG. 1B, the thickness of the base 10 in the Z-axis direction is formed to be thicker than the thickness of the vibrating arms 11a, 11b, and 11c in the Z-axis direction.
Further, as indicated by a two-dot chain line in FIG. 1A, on the main surface 10b side of both ends in the X-axis direction of the base portion 10, fixing portions 10c and 10d which are fixing regions to external members such as a package are provided. Is provided. In addition, it is preferable that the fixing | fixed part 10c, 10d is provided in the edge part on the opposite side to the vibrating arms 11a, 11b, 11c side of the base 10 in the Y-axis direction.

By the way, in the quartz crystal resonator element 1, each component is formed by etching using a photolithography technique.
Here, as the first electrodes 12a1, 12b1, and 12c1 of the excitation electrodes 12a, 12b, and 12c, films containing ITO (hereinafter referred to as ITO films: having optical transparency) are used. Therefore, in the crystal vibrating piece 1, the irradiation light irradiated from the main surface 10a side of the vibrating arms 11a, 11b, and 11c at the time of exposure for patterning the resist is formed on the main surface 10a side by sputtering or the like. Will penetrate the ITO film.
The transmitted irradiation light is reflected by an inclined surface (not shown) on the main surface 10b side of the vibrating arms 11a, 11b, and 11c having light transmission like the ITO film, and the resist is exposed from the main surface 10b side (first exposure portion). There is a risk of irradiating a portion which should not be exposed when forming one electrode 12a1, 12b1, 12c1.

To solve this problem, the quartz crystal resonator element 1 is formed by stacking an Mo (molybdenum) film or an Au film on the side on which the insulator 14 is provided of the ITO film that becomes the first electrodes 12a1, 12b1, and 12c1 in the manufacturing process. By forming the film, the transmission of the irradiation light is blocked, the resist is normally patterned, and the first electrodes 12a1, 12b1, 12c1 are devised so as to be formed in a predetermined shape.
Note that the quartz crystal resonator element 1 uses an Mo film or an Au film as a film that blocks the transmission of irradiation light (hereinafter referred to as a light shielding film), so that Al (as a light shielding film) can be used when developing with an alkaline developer. Electrolytic corrosion of the ITO film that occurs remarkably when the (aluminum) film is used is avoided.

Here, the operation of the crystal vibrating piece 1 will be described.
As shown in FIG. 2, the excitation electrodes 12a, 12b, and 12c of the quartz crystal vibrating piece 1 are driven by the first electrodes 12a1, 12b1, and 12c1 and the second electrodes 12a2, 12b2, and 12c2 being connected to an AC power source by cross wiring. An alternating voltage as a voltage is applied.

  Specifically, the first electrode 12a1 of the vibrating arm 11a, the second electrode 12b2 of the vibrating arm 11b, and the first electrode 12c1 of the vibrating arm 11c are connected to be at the same potential, and the second electrode 12a1 of the vibrating arm 11a is connected. The electrode 12a2, the first electrode 12b1 of the vibrating arm 11b, and the second electrode 12c2 of the vibrating arm 11c are connected to have the same potential.

In this state, when an alternating voltage is applied between the first electrode 12a1, 12b1, 12c1 and the second electrode 12a2, 12b2, 12c2, the first electrode 12a1, 12b1, 12c1 and the second electrode 12a2, 12b2, 12c2 An electric field is generated between them, and the piezoelectric body 13 is distorted by the inverse piezoelectric effect, and the piezoelectric body 13 expands and contracts in the Y-axis direction.
In the quartz crystal resonator element 1, the direction of the electric field generated at the excitation electrodes 12a and 12c and the direction of the electric field generated at the excitation electrode 12b by the cross wiring are opposite to each other, and the expansion and contraction of the piezoelectric body 13 is caused by the vibration arms 11a and 11c. And the vibrating arm 11b.
Specifically, when the piezoelectric body 13 of the vibrating arms 11a and 11c expands, the piezoelectric body 13 of the vibrating arm 11b contracts, and when the piezoelectric body 13 of the vibrating arms 11a and 11c contracts, the piezoelectric body of the vibrating arm 11b. 13 expands.

By such expansion and contraction of the piezoelectric body 13, the quartz crystal resonator element 1 has the vibrating arms 11 a, 11 b, and 11 c bent in the direction of the solid arrow when the alternating voltage is one potential, and when the alternating voltage is the other potential. The vibrating arms 11a, 11b, and 11c are bent in the direction of the dashed arrow.
By repeating this, in the quartz crystal vibrating piece 1, the vibrating arms 11a, 11b, and 11c undergo bending vibration (out-of-plane vibration) in the Z-axis direction. At this time, adjacent vibrating arms (here, 11a and 11b, 11b and 11c) bend and vibrate in opposite directions (in reverse phase).

As described above, the quartz crystal resonator element 1 of the present embodiment includes the first electrodes 12a1, 12b1, 12c1, and the second electrodes 12a2, 12b2, of the excitation electrodes 12a, 12b, 12c provided on the vibrating arms 11a, 11b, 11c. Since ITO is used for 12c2, the fall of Q value is suppressed by the characteristic of ITO, and Q value can be improved with respect to the prior art which uses Ti / Au.
This depends on the knowledge obtained by the inventors from the results of analysis by experiments (details will be described later).

  In the quartz crystal resonator element 1, the excitation electrodes 12 a, 12 b, 12 c have the insulator 14 between the first electrodes 12 a 1, 12 b 1, 12 c 1 and the piezoelectric body 13. Thus, the Q value can be drastically improved as compared with the conventional technique using Ti / Au.

Further, since the quartz crystal resonator element 1 uses SiO ₂ for the insulator 14, due to the characteristics of SiO ₂ , for example, the orientation of the piezoelectric body 13 during polarization is improved, and the Q value is further reduced. It is suppressed and the Q value can be dramatically improved as compared with the conventional technique using Ti / Au.
In addition, since the crystal vibrating piece 1 uses SiO ₂ for the insulator 14, for example, the temperature characteristics of the SiO ₂ and the first electrodes 12a1, 12b1, 12c1 and the second electrode 12a2 using ITO are used. , 12b2 and 12c2 are offset, it is possible to suppress frequency fluctuations caused by temperature changes.

  Further, since the crystal vibrating piece 1 uses ZnO for the piezoelectric body 13, it has excellent stretchability at the time of electric field application due to its high orientation, and efficiently vibrates and vibrates the vibrating arms 11a, 11b, and 11c. be able to.

The above will be described with reference to the drawings.
FIG. 3 is a diagram showing the relationship between the material of each component of the excitation electrode and the Q value in the quartz crystal resonator element. FIG. 3 summarizes the analysis results of the experiments using the inventors' samples.
Each sample of FIG. 3 has a configuration in which the outer size is common and only the material of each component of the excitation electrode is different. Moreover, the Q value described uses the data derived | led-out based on the frequency measurement value of each sample by frequency measuring devices, such as a laser Doppler vibrometer, for example.
In FIG. 3, for convenience, the insulator 14 is an insulator A, and an insulator (not used in the present embodiment) provided between the piezoelectric body 13 and the second electrodes 12 a 2, 12 b 2, and 12 c 2 is insulated. The body B is assumed.
Moreover, in FIG. 3, the comparison judgment result of the improvement degree of Q value with respect to the conventional structure product (No. 1) of each sample is described in two stages of ○ (good) and ◎ (excellent).

As shown in FIG. The conventional structure product based on the prior art No. 1 has a Q value of 2500.
On the other hand, no. Since the Q value of the present embodiment product 2 is 9000, the Q value is dramatically higher than the conventional structure product using Ti / Au for the first electrodes 12a1, 12b1, 12c1 and the second electrodes 12a2, 12b2, 12c2. It can be seen that the value has improved.
No. Since the Q value is 9000 in the first modification in which the insulator B is added to the product of this embodiment, the insulator B is added between the piezoelectric body 13 and the second electrodes 12a2, 12b2, and 12c2. Even so, it can be seen that further improvement of the Q value cannot be expected with respect to the present embodiment product.

No. 4, the second electrode 12a2, 12b2, 12c2 of the product of the present embodiment is changed to a Cr / Au film (a film in which Cr is used for the base layer and Au is used for the upper layer), and the product of the second modification has a Q value of 9000. Therefore, it can be seen that the second electrodes 12a2, 12b2, and 12c2 of the present embodiment product are not necessarily ITO films.
No. 5, the third modified example in which the insulator 14 (insulator A) is removed from the product of the present embodiment has a Q value of 3500, so the Q value is improved compared to the conventional structure product. It can be seen that the insulator 14 is necessary for further improvement of the value.

No. 6, the insulator 4 (insulator A) is removed from the product of the present embodiment and the insulator 4 is added to the modified product 4 having a Q value of 3500. Although improved, even if the insulator 14 is removed from the product of the present embodiment and the insulator B is added between the piezoelectric body 13 and the second electrodes 12a2, 12b2, and 12c2, the Q value can be further improved. You can see that you ca n’t expect.
That is, it can be said that it was proved again that the insulator 14 is necessary between the first electrodes 12a1, 12b1, 12c1 and the piezoelectric body 13 in order to further improve the Q value.

No. 7 in which the first electrodes 12a1, 12b1 and 12c1 of the product of the present embodiment are replaced with a Ti / Au film of the prior art, the insulator 14 (insulator A) is removed, and the insulator B is added. Since Q value is 3500, it turns out that Q value improves rather than a conventional structure product by changing only 2nd electrode 12a2, 12b2, 12c2 of a conventional structure product into an ITO film.
No. 4, no. From the result of No. 7, the quartz resonator element can be improved in Q value over the conventional structure product by using at least one of the first electrodes 12a1, 12b1, 12c1 and the second electrodes 12a2, 12b2, 12c2 as an ITO film. It can be said that it was supported.

  As described above, according to the analysis result of the experiment using the samples of the inventors, the quartz crystal vibrating piece 1 of the present embodiment and the quartz crystal vibrating piece of each modification are both in comparison with the quartz crystal vibrating piece of the conventional structure. It was confirmed that the Q value was improved.

Further, since the crystal vibrating piece 1 is provided with the fixing portions 10c and 10d at both ends in the X-axis direction of the base portion 10, the path from the vibrating arms 11a, 11b and 11c to the fixing portions 10c and 10d of the base portion 10 is provided. Can be made longer compared to the case where the fixing portions 10c and 10d are provided in other portions.
As a result, in the quartz crystal resonator element 1, when the fixing portions 10c and 10d of the base portion 10 are fixed to the external member, vibration energy leaking to the external member via the fixing portions 10c and 10d is reduced by the fixing portions 10c and 10d. Since it decreases compared to the case where it is provided in the portion (for example, the case where the fixing portions 10c, 10d are provided in the vicinity of the vibrating arms 11a, 11b, 11c), the reduction in the Q value is suppressed. Can do.

  In addition, since the quartz crystal resonator element 1 uses quartz as a base material, it is excellent in workability due to its characteristics and can stably vibrate regardless of ambient temperature changes.

(Other variations)
Here, another modification of the first embodiment will be described.
In the first embodiment, the crystal vibrating piece using quartz as the base material has been described, but the vibrating piece may be a silicon vibrating piece using silicon as the base material.
The configuration of the silicon vibrating piece is basically the same as the configuration of the quartz crystal vibrating piece 1 shown in FIGS. 1 and 2, and the material (material) of the base material is different from that of the quartz crystal vibrating piece 1.
Similar to the quartz crystal resonator element 1, the silicon resonator element can be combined with the constituent elements of the excitation electrode shown in FIG. 3.

In the case where the silicon vibrating piece is silicon, for example, single crystal silicon doped with impurities such as phosphorus or boron, or low resistance silicon such as polysilicon, the vibrating arms 11a, 11b, and 11c shown in FIGS. It is preferable to provide an insulating film (insulator) using SiO ₂ between the main surface 10a of the first electrode 12a1, 12b1, and 12c1.
Thereby, the silicon vibrating reed can reliably perform the insulation separation between the vibrating arms 11a, 11b, and 11c and the first electrodes 12a1, 12b1, and 12c1.

As described above, since the silicon vibrating piece uses silicon for the base material, it is possible to make the potential performance related to the Q value higher than that of the quartz crystal vibrating piece 1 due to its characteristics (for example, in a single base material) Q value can be about 10 times that of quartz).
The inventors have confirmed that the effect of suppressing the deterioration of the Q value in the silicon vibrating piece is equivalent to that of the quartz vibrating piece 1.

Since the silicon vibrating piece uses silicon (non-light-transmitting material) as a base material, unnecessary exposure at the time of forming the first electrodes 12a1, 12b1, and 12c1, which is necessary for the quartz vibrating piece 1, is avoided. A light shielding film becomes unnecessary. Thereby, the silicon vibrating piece can improve the productivity at the time of manufacture as compared with the quartz vibrating piece 1.
Note that the base material of the resonator element may be made of a material other than quartz or silicon and having a Q value similar to that of quartz or silicon.

(Second Embodiment)
Next, a crystal resonator as a resonator including the crystal resonator element described in the first embodiment will be described.
FIG. 4 is a schematic diagram illustrating a schematic configuration of the crystal resonator according to the second embodiment. 4A is a plan view seen from the lid (lid body) side, and FIG. 4B is a cross-sectional view taken along the line CC in FIG. 4A. In the plan view, the lid is omitted. Each wiring is omitted.
In addition, the same code | symbol is attached | subjected to a common part with the said 1st Embodiment, detailed description is abbreviate | omitted, and it demonstrates centering on a different part from the said 1st Embodiment.

  As shown in FIG. 4, the crystal resonator 5 includes either the crystal vibrating piece 1 described in the first embodiment or the crystal vibrating piece of each modified example (here, the crystal vibrating piece 1), and the crystal vibrating piece. 1 and a package 20 containing 1.

The package 20 includes a package base 21 having a substantially rectangular planar shape and a recess, and a lid 22 having a substantially rectangular planar shape covering the recess of the package base 21 and is formed in a substantially rectangular parallelepiped shape. Yes.
The package base 21 is made of an aluminum oxide sintered body, crystal, glass, silicon, or the like formed by laminating and firing ceramic green sheets.
The lid 22 is made of the same material as the package base 21 or a metal such as Kovar, 42 alloy, or stainless steel.

The package base 21 is provided with internal terminals 24 and 25 on an inner bottom surface (a bottom surface inside the recess) 23.
The internal terminals 24 and 25 are formed in a substantially rectangular shape at positions near the connection electrodes 18 a and 18 b provided on the base 10 of the crystal vibrating piece 1. The connection electrodes 18a and 18b are connected to the first electrode (12b1 and the like) and the second electrode (12b2 and the like) of each excitation electrode (12b and the like) of the crystal vibrating piece 1 by a wiring (not shown).
For example, in the wiring of FIG. 2, the wiring on one side of the AC power supply is connected to the connection electrode 18a, and the wiring on the other side is connected to the connection electrode 18b.

A pair of external terminals 27 and 28 used for mounting on an external member such as an electronic device are formed on the outer bottom surface (the surface opposite to the inner bottom surface 23, the outer bottom surface) 26 of the package base 21. .
The external terminals 27 and 28 are connected to the internal terminals 24 and 25 by internal wiring (not shown). For example, the external terminal 27 is connected to the internal terminal 24, and the external terminal 28 is connected to the internal terminal 25.
The internal terminals 24 and 25 and the external terminals 27 and 28 are made of a metal film obtained by laminating each film such as Ni (nickel) and Au on a metallized layer such as W (tungsten) and Mo by a method such as plating.

In the crystal resonator 5, the fixing portions 10 c and 10 d of the base portion 10 of the crystal resonator element 1 are fixed to the inner bottom surface 23 of the package base 21 via an adhesive 30 such as epoxy, silicone, or polyimide. .
In the crystal resonator 5, the connection electrodes 18 a and 18 b of the crystal resonator element 1 are connected to the internal terminals 24 and 25 by metal wires 31 such as Au and Al.
In the crystal resonator 5, the concave portion of the package base 21 is covered with the lid 22 in a state where the crystal resonator element 1 is connected to the internal terminals 24 and 25 of the package base 21, and the package base 21 and the lid 22 are seamed. The inside of the package 20 is hermetically sealed by being joined by a joining member 29 such as low-melting glass or adhesive.
Note that the inside of the package 20 is in a reduced pressure state (high vacuum state) or in a state filled with an inert gas such as nitrogen, helium, or argon.

The package may include a flat package base and a lid having a recess. The package may have a recess in both the package base and the lid.
Further, the base portion 10 of the quartz crystal resonator element 1 is replaced with the fixing portions 10c and 10d, and is a portion other than the fixing portions 10c and 10d, for example, a portion including a center of a straight line connecting the fixing portion 10c and the fixing portion 10d. It may be fixed in place.
According to this, the quartz crystal resonator element 1 can suppress distortion of the base 10 due to the thermal stress generated in the fixing portion by being fixed at one place.

  The crystal resonator 5 is driven by a drive signal (alternating voltage) applied to the excitation electrode (12b, etc.) via the external terminals 27 and 28, the internal terminals 24 and 25, the metal wire 31, and the connection electrodes 18a and 18b. Each vibrating arm (11b, etc.) of the resonator element 1 oscillates (resonates) in the thickness direction (the arrow direction in FIG. 4B) at a predetermined frequency (for example, about 32 kHz).

As described above, since the crystal resonator 5 according to the second embodiment includes the crystal resonator element 1, a resonator that exhibits the effect described in the first embodiment (for example, suppresses a decrease in Q value). In addition, it is possible to provide a vibrator that can improve the Q value with respect to the prior art.
Note that the crystal resonator 5 can provide a resonator having the same effect as described above even when the crystal resonator element of each modification is provided instead of the crystal resonator element 1.
The quartz resonator 5 is similar to the above in the case where a silicon resonator element of another modification is provided instead of the quartz resonator element 1 (in this case, the quartz resonator 5 is a silicon resonator). A vibrator having an effect can be provided.

(Third embodiment)
Next, a crystal oscillator as an oscillator including the crystal resonator element described in the first embodiment will be described.
FIG. 5 is a schematic diagram showing a schematic configuration of the crystal oscillator of the third embodiment. FIG. 5A is a plan view seen from the lid side, and FIG. 5B is a cross-sectional view taken along the line CC in FIG. 5A. In the plan view, the lid and some components are omitted. Each wiring is omitted.
In addition, the same code | symbol is attached | subjected to the common part with the said 1st Embodiment and 2nd Embodiment, detailed description is abbreviate | omitted, and it demonstrates centering on a different part from the said 1st Embodiment and 2nd Embodiment. .

  As shown in FIG. 5, the crystal oscillator 6 includes either the crystal vibrating piece 1 described in the first embodiment or the crystal vibrating piece of each modified example (here, the crystal vibrating piece 1) and the crystal vibrating piece 1. IC chip 40 as an oscillation circuit that oscillates and a package 20 containing crystal resonator element 1 and IC chip 40.

An internal connection terminal 23 a is provided on the inner bottom surface 23 of the package base 21.
The IC chip 40 incorporating the oscillation circuit is fixed to the inner bottom surface 23 of the package base 21 using an adhesive (not shown).
In the IC chip 40, a connection pad (not shown) is connected to the internal connection terminal 23a by a metal wire 41 such as Au or Al.

The internal connection terminal 23a is made of a metal film in which a film such as Ni or Au is laminated on a metallized layer such as W or Mo by plating or the like, and is connected to external terminals 27 and 28 of the package 20 via internal wiring (not shown). It is connected to internal terminals 24, 25 and the like.
For connecting the connection pads of the IC chip 40 and the internal connection terminals 23a, a connection method by flip chip mounting by inverting the IC chip 40 is used in addition to a connection method by wire bonding using the metal wire 41. May be.

The crystal oscillator 6 generates a crystal resonator element according to a drive signal applied from the IC chip 40 to the excitation electrode (12b, etc.) via the internal connection terminals 23a, the internal terminals 24 and 25, the metal wires 31, and the connection electrodes 18a and 18b. Each vibrating arm (such as 11b) oscillates (resonates) at a predetermined frequency (for example, about 32 kHz).
Then, the crystal oscillator 6 outputs an oscillation signal generated along with this oscillation to the outside via the IC chip 40, the internal connection terminal 23a, the external terminals 27 and 28, and the like.

As described above, since the crystal oscillator 6 of the third embodiment includes the crystal resonator element 1, an oscillator that exhibits the effect described in the first embodiment (for example, suppresses a decrease in the Q value, An oscillator capable of improving the Q value with respect to the technology can be provided.
Note that the crystal oscillator 6 can provide an oscillator that exhibits the same effect as described above even when the crystal resonator element of each modification is provided instead of the crystal oscillator piece 1.
The crystal oscillator 6 has the same effect as described above even when the silicon resonator element of another modification is provided instead of the crystal resonator element 1 (in this case, the crystal oscillator 6 is a silicon oscillator). An oscillator can be provided.
In the crystal oscillator 6 (silicon oscillator), the IC chip 40 is not built in the package 20, but a module structure in which the IC chip 40 is externally attached (for example, a crystal oscillator (silicon oscillator) and an IC chip are individually provided on one substrate). Or a structure mounted on

(Fourth embodiment)
Next, a mobile phone as an electronic apparatus including the quartz crystal resonator element described in the first embodiment will be described.
FIG. 6 is a schematic perspective view showing the mobile phone of the fourth embodiment.
A cellular phone 700 shown in FIG. 6 includes the crystal resonator element 1 described in the first embodiment as a reference clock oscillation source and the like, and further includes a liquid crystal display device 701, a plurality of operation buttons 702, an earpiece 703, and a transmitter. A mouth 704 is provided. Note that the mobile phone 700 may include the quartz crystal resonator element of each modified example or a silicon vibrating piece of another modified example instead of the quartz crystal vibrating piece 1.

  Any of the above-described quartz vibrating piece 1, the quartz vibrating piece of each modified example, and the silicon vibrating piece of another modified example is not limited to the above mobile phone, but an electronic book, a personal computer, a television, a digital still camera, and a video camera. , Video recorders, navigation devices, pagers, electronic notebooks, calculators, word processors, workstations, videophones, POS terminals, reference clock oscillation sources for devices equipped with touch panels, etc. It is possible to provide an electronic device that exhibits the effects described in the above embodiments and modifications.

For example, a Z-cut plate, an X-cut plate, or the like cut out from a raw crystal or the like at a predetermined angle can be used as the crystal serving as the base material of the crystal vibrating piece 1. When a Z-cut plate is used, the etching process is easy due to the characteristics, and when an X-cut plate is used, the temperature-frequency characteristics are good due to the characteristics.
The vibration direction of the resonator element is not limited to the Z-axis direction (thickness direction). For example, by providing excitation electrodes on the side surfaces (surfaces connecting the main surfaces) of the vibrating arm, the X-axis direction (The direction along the main surface) may be used (the bending vibration in this direction is called in-plane vibration).
Further, the number of vibrating arms of the vibrating piece is not limited to three, and may be 1, 2, 4, 5, or n (n is a natural number of 6 or more).
Note that the thickness of the base of the resonator element may be the same as that of the vibrating arm. According to this, since the resonator element has a flat plate shape, the manufacture becomes easy.

  DESCRIPTION OF SYMBOLS 1 ... Crystal vibrating piece as a vibrating piece, 5 ... Crystal oscillator as a vibrator, 6 ... Crystal oscillator as an oscillator, 10 ... Base part, 10a, 10b ... Main surface, 10c, 10d ... Fixed part, 11a, 11b, 11c ... vibrating arm, 12a, 12b, 12c ... excitation electrode, 12a1, 12b1, 12c1 ... first electrode, 12a2, 12b2, 12c2 ... second electrode, 13 ... piezoelectric body, 14 ... insulator, 18a, 18b ... connection electrode 20 ... package, 21 ... package base, 22 ... lid, 23 ... inner bottom surface, 23a ... internal connection terminal, 24,25 ... internal terminal, 26 ... outer bottom surface, 27,28 ... external terminal, 29 ... joining member, 30 ... Adhesive, 31 ... Metal wire, 40 ... IC chip as oscillation circuit, 41 ... Metal wire, 700 ... Cell phone as electronic device, 701 ... Liquid crystal display, 702 ... Create button, 703 ... earpiece, 704 ... mouthpiece.

Claims (9)

A base including a base and a vibrating arm extending from the base;
A first electrode provided on the vibrating arm;
A second electrode provided above the first electrode;
A piezoelectric body disposed between the first electrode and the second electrode,
A vibrating piece using ITO as a material of at least one of the first electrode and the second electrode.   2. The resonator element according to claim 1, further comprising an insulator between the first electrode and the piezoelectric body. The vibrating element according to claim 2, the material of the insulator, resonator element, characterized in that by using SiO _2.   4. The resonator element according to claim 1, wherein ZnO is used as a material of the piezoelectric body. 5.   5. The resonator element according to claim 1, wherein quartz is used as a material of the base material.   5. The resonator element according to claim 1, wherein silicon is used as a material for the base material. A resonator element according to any one of claims 1 to 6,
A package containing the resonator element;
A vibrator characterized by comprising: A resonator element according to any one of claims 1 to 6,
An oscillation circuit for oscillating the resonator element;
An oscillator comprising:   An electronic device comprising the resonator element according to any one of claims 1 to 6.

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