JP2010103805A - Bending vibration piece, bending vibrator, and piezoelectric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress fluctuation of a Q value resulting from a thermoelastic effect. <P>SOLUTION: A through hole 7 is formed between a first surface 11 and a second surface 12 which alternately extends and are compressed by bending vibration, since the through hole 7 is formed over a base part 2 from a bending vibration part 1, a heat transmission route can not be secured between the first surface 11 and the second surface 12, and can be shielded by the through hole 7. Thus, since the heat transmission route between the first surface 11 and the second surface 12 is shielded by the through hole 7 not only at the bending vibration part 1 but at the base part 2, relaxation oscillation inversely proportional to buffer time until temperature equilibration is performed by heat transmission (heat conduction) is eliminated to suppress inhibition of a bending vibration frequency. Thus, the fluctuation of Q value resulting from the thermoelastic effect is suppressed to attain miniaturization of a crystal vibration chip 10. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bending vibration piece, a bending vibrator, and a piezoelectric device.

Conventionally, it is known that when a flexural vibration piece is miniaturized, the Q value becomes small and the flexural vibration is inhibited. This is due to the thermoelastic effect that occurs when the relaxation vibration that is inversely proportional to the relaxation time until the temperature is balanced by the movement of heat and the vibration frequency of the flexural vibration piece approach each other. That is, elastic deformation is caused by bending vibration of the bending vibration piece, the temperature of the surface to be compressed is increased, and the temperature of the surface to be expanded is decreased, so that a temperature difference is generated inside the bending vibration piece. Bending vibration is inhibited and the Q value is lowered by relaxation vibration that is inversely proportional to the relaxation time until the temperature difference is balanced by heat conduction.
For this reason, a groove or a through-hole is formed in the bending vibration portion of the bending vibration piece to prevent the movement of heat generated on the surface that is expanded from the surface to be compressed of the vibrator, and the Q value resulting from the thermoelastic effect Fluctuation is suppressed (see, for example, Patent Document 1).

Japanese Utility Model Publication No. 2-32229 (pages 4 to 5, FIGS. 1 to 3)

  However, even if the above-described conventional technique is used, the Q value deterioration due to the thermoelastic effect is not sufficiently improved. The inventors of the present application newly found the existence of a phenomenon in which a part of heat generated by bending vibration moves around a groove or a through hole provided in the bending vibration portion, and the movement of heat is bent. It has also been newly found that it becomes particularly prominent on the base side (the base side, not the free end side) of the groove or the through-hole provided in the vibration part. That is, in the above-described prior art, since the through groove or the through hole is not formed up to the one end side where the bending vibration piece is fixed, heat transfer occurs at one end side. Heat transfer cannot be prevented between the stretched surface and the compressed surface. For this reason, there exists a subject that it is difficult to suppress the fluctuation | variation of Q value resulting from a thermoelastic effect.

  The present invention is based on a new discovery that the Q value deterioration caused by the thermoelastic effect occurs not only in the bending vibration part that performs bending vibration but also in the base part connected to the bending vibration part. It was made to solve at least a part. It can be realized by the following forms or application examples.

  [Application Example 1] A bending vibration piece according to this application example includes a base and a bending vibration part that is formed extending from the base and bends and vibrates. The bending vibration parts are arranged to be opposed to each other and bend. A first surface and a second surface that alternately expand and compress by vibration, and a through-hole penetrating between the first surface and the second surface, the through-hole from the bending vibration portion The gist is that it is formed across the base.

  According to this, since the through hole is formed between the first surface and the second surface that are alternately expanded and compressed by the bending vibration, and the through hole is formed from the bending vibration portion to the base portion, A heat transfer path between the first surface and the second surface cannot be secured and can be blocked by the through hole. In this way, the heat transfer path between the first surface and the second surface is blocked not only by the bending vibration part but also by the through-hole at the base part, so that the temperature balance is achieved by heat transfer (heat conduction). It is possible to eliminate relaxation vibration that is inversely proportional to the buffer time, and to inhibit the bending frequency from being inhibited. Thereby, the fluctuation | variation of Q value resulting from a thermoelastic effect can be suppressed, and size reduction of a bending vibration piece can be implement | achieved.

  Application Example 2 In the bending vibration piece according to the application example described above, of the end portions of the through hole, all the end portions provided in the bending vibration portion are half the length in the extension direction of the bending vibration portion. It is preferable that it is arrange | positioned from the position of the said base side.

  According to this, since the through-hole is arranged from the base portion, which is a relatively large portion of heat transfer due to bending vibration, to the base portion side from the half of the length in the extending direction of the bending vibration portion, the above-mentioned There is an effect. And the mechanical strength of the part (free end side) exceeding half the length of the extension direction of the bending vibration part which is a part with comparatively little heat transfer by bending vibration is securable.

  Application Example 3 A bending vibrator according to this application example includes the bending vibration piece described above and a package that houses the bending vibration piece, and the bending vibration piece is hermetically sealed in the package. It is a summary.

  According to this, the bending vibrator can exhibit the same effect as described above.

  Application Example 4 A piezoelectric device according to this application example includes the bending vibration piece described above, an IC chip that drives the bending vibrator, and a package that houses the bending vibration piece and the IC chip. The gist is that the flexural vibration piece and the IC chip are hermetically sealed in the package.

  According to this, the piezoelectric device can exhibit the same effects as described above.

  In the following embodiments, a quartz crystal vibrating piece made of quartz, which is a kind of piezoelectric body, will be described as an example of the bending vibrating piece. Then, as a piezoelectric vibrator and a piezoelectric device using the crystal vibrating piece, a crystal vibrator and a crystal oscillator will be described as examples.

(First embodiment)
The first embodiment will be described below with reference to FIGS. 1 and 2.
FIG. 1 is a schematic diagram illustrating a quartz crystal resonator element 10 according to the first embodiment. FIG. 2 is a schematic cross-sectional view of FIG.

FIG. 1A is a schematic front view of the quartz crystal vibrating piece 10. FIG. 1B is a schematic side view of FIG.
As shown in FIG. 1, the quartz crystal vibrating piece 10 includes a bending vibration portion 1, a base portion 2, a through hole 7, and fixed electrodes 5 and 6.

  The bending vibration part 1 is formed extending from the base part 2. The bending vibration part 1 includes a first surface 11 and a second surface 12 that are arranged to face each other, and a third surface 13 and a fourth surface 14 that are arranged to face each other.

  The through hole 7 is formed to penetrate between the third surface 13 and the fourth surface 14. The through hole 7 is disposed between the first surface 11 and the second surface 12. Further, the through hole 7 is formed from the bending vibration portion 1 to the base portion 2. And the through-hole 7 is formed from the position of the half of the length of the direction where the bending vibration part 1 extends from the base 2 to the base 2 side.

  The fixed electrodes 5 and 6 are disposed on the base 2. Wiring is performed between the fixed electrodes 5 and 6 so that an alternating current flows.

  The flexural vibration portion 1, the base portion 2, and the through-hole 7 are formed by wet etching or the like after being cut out from a quartz crystal. The fixed electrodes 5 and 6 include a base layer made of chromium (Cr) or nickel (Ni) and an electrode layer made of gold (Au) or silver (Ag) on the base layer. These underlayer and electrode layer are formed by vapor deposition or sputtering.

As the bending vibration part 1 bends and vibrates due to out-of-plane vibration indicated by a solid line arrow and a two-dot chain line arrow, the first surface 11 and the second surface 12 are alternately compressed and expanded. The out-of-plane vibration refers to vibration accompanied by a displacement that is substantially perpendicular to both the extending direction of the bending vibration part 1 and the width direction of the bending vibration part 1.
When the first surface 11 is compressed, the second surface 12 is stretched. Conversely, when the first surface 11 is stretched, the second surface 12 is compressed. In this way, the first surface 11 and the second surface 12 that are disposed to face each other alternately expand and compress due to the bending vibration of the bending vibration portion 1.

Fig.2 (a) is AA schematic sectional drawing of FIG.1 (b). FIG. 2B is a schematic cross-sectional view taken along the line BB in FIG.
As shown in FIG. 2A, the excitation electrode 3 is formed on the first surface 11 and the second surface 12 of the bending vibration unit 1. The excitation electrode 4 is formed on the third surface 13 and the fourth surface 14 of the bending vibration part 1.
As shown in FIG. 2B, the excitation electrode 4 is formed in the through hole 7. The excitation electrode 3 is formed on the first surface 11 and the second surface 12 in the same manner as in FIG.
In this way, the excitation electrodes 3 and 4 are wired so that an alternating current flows.

  The excitation electrodes 3 and 4 include a base layer such as chromium (Cr) or nickel (Ni) and an electrode layer made of gold (Au) or silver (Ag) on the base layer. These underlayer and electrode layer are formed by vapor deposition or sputtering.

  The excitation electrode 3 is connected to the fixed electrode 5, and the excitation electrode 4 is connected to the fixed electrode 6 (not shown). By passing an alternating current between the fixed electrodes 5 and 6, an alternating current flows between the excitation electrodes 3 and 4. As a result, an electric field is generated in the bending vibration portion 1 sandwiched between the excitation electrodes 3 and 4. Since the positive and negative charges are alternately charged on the excitation electrodes 3 and 4, the direction of the electric field changes. Depending on the direction in which the electric field is generated, the first surface 11 and the second surface 12 are stretched and compressed by the piezoelectric effect. In this way, the flexural vibration unit 1 performs flexural vibration indicated by solid line arrows and two-dot chain line arrows in FIG.

  Further, the fixed electrode 5 and the fixed electrode 6 are also used for fixing to a package (not shown) for housing the crystal vibrating piece 10.

  Therefore, according to the present embodiment, the through hole 7 is formed between the first surface 11 and the second surface 12 that alternately expand and compress by bending vibration, and the through hole 7 extends from the bending vibration portion 1 to the base portion 2. Therefore, the heat transfer path between the first surface 11 and the second surface 12 cannot be ensured and can be blocked by the through hole 7. In this way, the heat transfer path between the first surface 11 and the second surface 12 is blocked not only by the bending vibration part 1 but also by the through hole 7 in the base part 2, so that heat transfer (heat conduction) It is possible to eliminate relaxation vibration that is inversely proportional to the buffer time until temperature equilibration, and to inhibit the bending frequency from being inhibited. Thereby, the fluctuation | variation of Q value resulting from a thermoelastic effect can be suppressed, and size reduction of the quartz crystal vibrating piece 10 is realizable.

  According to this, since the through-hole 7 is arranged from the base 2 which is a relatively large portion of the heat transfer due to the bending vibration to the base 2 side from a position half the length of the bending vibration part 1 in the extending direction. The above-described effects can be achieved. And the mechanical strength of the part (free end side) exceeding half of the length of the extension direction of the bending vibration part 1 which is a part with comparatively little heat transfer by bending vibration is securable.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to FIGS. 3 and 4.
FIG. 3 is a schematic view showing the crystal vibrating piece 20 of the second embodiment. FIG. 4 is a schematic cross-sectional view of FIG.

  The crystal vibrating piece 20 according to the second embodiment is different in that it includes two bending vibration portions 1 according to the first embodiment shown in FIGS. 1 and 2. For this reason, the same code | symbol is provided and description of a structure is abbreviate | omitted.

FIG. 3A is a schematic front view of the crystal vibrating piece 20. FIG. 3B is a schematic side view of FIG.
As shown in FIG. 3, the quartz crystal vibrating piece 20 includes two bending vibration portions 1 (1 </ b> A and 1 </ b> B), a base portion 2, two through holes 7, and fixed electrodes 5 and 6.

  The two bending vibration parts 1 (1A, 1B) are formed extending from the base part 2, respectively. The two bending vibration parts 1 are each formed with a through hole 7.

As the bending vibration part 1 (1A, 1B) bends and vibrates due to out-of-plane vibration indicated by a solid arrow and a two-dot chain line arrow, the first surface 11 and the second surface 12 are alternately compressed and expanded. As described in the first embodiment, the out-of-plane vibration is vibration accompanied by a displacement that is substantially perpendicular to both the extending direction of the bending vibration unit 1 and the width direction of the bending vibration unit 1. In particular, in the case of the present embodiment, the out-of-plane vibration is vibration with displacement that is substantially perpendicular to both the extending direction of the bending vibration portion 1 (1A, 1B) and the arrangement direction of the bending vibration portion 1 (1A, 1B). It can also be explained.
When the first surface 11 is compressed, the second surface 12 is stretched. Conversely, when the first surface 11 is stretched, the second surface 12 is compressed. In this way, the first surface 11 and the second surface 12 that are arranged to face each other alternately expand and compress due to the bending vibration of the bending vibration portion 1 (1A, 1B).

Fig.4 (a) is AA schematic sectional drawing of FIG.3 (b). FIG. 4B is a schematic cross-sectional view taken along the line BB in FIG.
As shown in FIG. 4A, excitation electrodes 3 and 4 are formed in the flexural vibration portion 1A in the same manner as in FIG. On the other hand, the excitation electrodes 3 and 4 are formed in the bending vibration part 1B differently from FIG. That is, the excitation electrode 4 is formed on the first surface 11 and the second surface 12 of the bending vibration portion 1B, and the excitation electrode 3 is formed on the third surface 13 and the fourth surface 14.
As shown in FIG. 4B, the excitation electrode 3 is formed on the first surface 11 and the second surface 12 in the flexural vibration portion 1A, as in FIG. 2B. On the other hand, the excitation electrodes 3 and 4 are formed in the bending vibration part 1B differently from FIG.2 (b). That is, the excitation electrode 4 is formed on the first surface 11 and the second surface 12 of the bending vibration part 1B. And the excitation electrode 3 is formed in the through-hole 7 of the bending vibration part 1B.
In this way, the excitation electrodes 3 and 4 are wired so that an alternating current flows.

  As described above, when the bending vibration part 1 </ b> A bends and vibrates as indicated by a solid line arrow by passing an alternating current between the excitation electrodes 3 and 4, the bending vibration part 1 </ b> B undergoes bending vibration as indicated by a two-dot chain line arrow. Conversely, when the bending vibration part 1A undergoes bending vibration indicated by a two-dot chain line arrow, the bending vibration part 1B undergoes bending vibration indicated by a solid line arrow.

  Therefore, according to this embodiment, the same effect as the above-mentioned embodiment can be produced.

(Third embodiment)
Hereinafter, the third embodiment will be described with reference to FIGS. 5 and 6.
FIG. 5 is a schematic view showing a crystal vibrating piece 30 according to the third embodiment. FIG. 6 is a schematic cross-sectional view of FIG.

  The difference between the crystal vibrating piece 30 of the third embodiment and the crystal vibrating piece 20 of the second embodiment shown in FIGS. 3 and 4 is the bending vibration direction of the bending vibration portion 1 (1A, 1B). For this reason, the same code | symbol is provided and description of a structure is abbreviate | omitted.

FIG. 5A is a schematic front view of the crystal vibrating piece 30. FIG. 5B is a schematic side view of FIG.
As shown in FIG. 5, the quartz crystal vibrating piece 30 includes two bending vibration portions 1 (1 </ b> A and 1 </ b> B), a base portion 2, two through holes 7, and fixed electrodes 5 and 6.

  The crystal vibrating piece 30 shown in FIG. 5 rotates the two bending vibration parts 1 (1A, 1B) and the two through holes 7 shown in FIG. 3 by 90 ° about the extending direction of the bending vibration part. It is the arrangement that was made.

As the bending vibration part 1 (1A, 1B) bends and vibrates due to the in-plane vibration indicated by the solid arrow and the two-dot chain arrow, the first surface 11 and the second surface 12 are alternately compressed and expanded.
When the first surface 11 is compressed, the second surface 12 is stretched. Conversely, when the first surface 11 is stretched, the second surface 12 is compressed. In this way, the first surface 11 and the second surface 12 that are arranged to face each other alternately expand and compress due to the bending vibration of the bending vibration portion 1 (1A, 1B).

Fig.6 (a) is AA schematic sectional drawing of Fig.5 (a). FIG.6 (b) is BB schematic sectional drawing of Fig.5 (a).
As shown in FIGS. 6A and 6B, excitation electrodes 3 and 4 are formed in the flexural vibration portions 1A and 1B in the same manner as in FIGS. 4A and 4B.
In this way, the excitation electrodes 3 and 4 are wired so that an alternating current flows.

  In this way, when an alternating current is passed between the excitation electrodes 3 and 4, when the bending vibration part 1A bends and vibrates as indicated by the solid line arrow, the bending vibration part 1B similarly performs bending vibration as indicated by the solid line arrow. Conversely, when the bending vibration part 1A undergoes bending vibration indicated by a two-dot chain line arrow, the bending vibration part 1B similarly performs bending vibration indicated by a two-dot chain line arrow.

  Therefore, according to this embodiment, the same effect as the above-mentioned embodiment can be produced.

(Fourth embodiment)
Hereinafter, the fourth embodiment will be described with reference to FIGS. 7 and 8.
FIG. 7 is a schematic view showing a crystal vibrating piece 40 of the fourth embodiment. FIG. 8 is a schematic cross-sectional view of FIG.

  The difference between the crystal vibrating piece 40 of the fourth embodiment and the crystal vibrating piece 30 of the third embodiment shown in FIGS. 5 and 6 is that the bending vibration part 1 (1A, 1B) is provided with the slit parts 16, respectively. Is a point. For this reason, the same code | symbol is provided and description of a structure is abbreviate | omitted.

FIG. 7A is a schematic front view of the crystal vibrating piece 40. FIG. 7B is a schematic side view of FIG.
As shown in FIG. 7, the quartz crystal vibrating piece 40 includes two bending vibration parts 1 (1 </ b> A and 1 </ b> B), a base part 2, two through holes 7, four slit parts 16, and a fixed electrode 5. , 6.

  A crystal vibrating piece 40 shown in FIG. 7 includes slit portions 16 on the third surface 13 and the fourth surface 14 of the bending vibration portion 1 (1A, 1B).

As the bending vibration part 1 (1A, 1B) bends and vibrates due to the in-plane vibration indicated by the solid arrow and the two-dot chain arrow, the first surface 11 and the second surface 12 are alternately compressed and expanded.
When the first surface 11 is compressed, the second surface 12 is stretched. Conversely, when the first surface 11 is stretched, the second surface 12 is compressed. In this way, the first surface 11 and the second surface 12 that are arranged to face each other alternately expand and compress due to the bending vibration of the bending vibration portion 1 (1A, 1B).

Fig.8 (a) is AA schematic sectional drawing of Fig.7 (a). FIG. 8B is a schematic cross-sectional view taken along the line BB in FIG.
As shown in FIG. 8A, the excitation electrode 4 is formed in the slit portion 16 of the bending vibration portion 1A. The excitation electrode 3 is formed in the slit portion 16 of the bending vibration portion 1B.
As shown in FIG. 8B, excitation electrodes 3 and 4 are formed in the bending vibration portions 1A and 1B in the same manner as in FIG. 6B.
In this way, the excitation electrodes 3 and 4 are wired so that an alternating current flows.

  In this way, when an alternating current is passed between the excitation electrodes 3 and 4, when the bending vibration part 1A bends and vibrates as indicated by the solid line arrow, the bending vibration part 1B similarly performs bending vibrations as indicated by the solid line arrow. Conversely, when the bending vibration part 1A undergoes bending vibration indicated by a two-dot chain line arrow, the bending vibration part 1B similarly performs bending vibration indicated by a two-dot chain line arrow.

  Therefore, according to this embodiment, the same effect as the above-mentioned embodiment can be produced.

(Fifth embodiment)
Hereinafter, a crystal resonator will be described as an example of the piezoelectric resonator of the fifth embodiment, and a description will be given with reference to FIGS. 9 and 10.

  The crystal resonator of the fifth embodiment is a crystal resonator using the crystal resonator element of the first to fourth embodiments. For this reason, the quartz crystal resonator element used for the quartz crystal resonator of the fifth embodiment has the same configuration as the quartz crystal resonator element of the first to fourth embodiments, so that the same reference numerals are given and description of the configuration is omitted. . Below, it demonstrates using the crystal vibrating piece 30 of 3rd Embodiment.

FIG. 9 is a schematic plan view of the crystal unit with the internal structure exposed except for the lid. FIG. 10 is a schematic cross-sectional view taken along the line XX in FIG. 9 and shows a lid disposed.
As shown in FIGS. 9 and 10, the crystal resonator 80 houses a crystal resonator element 30 in a package 31. Specifically, as shown in FIG. 10, the crystal resonator 80 includes a first substrate 34, a crystal 31 in a package 31 including a second substrate 35 and a third substrate 36 stacked on the first substrate 34. The vibrating piece 30 is accommodated.

  The package 31 constitutes a first substrate 34, a second substrate 35, and a third substrate 36 which are insulating bases. The second substrate 35 includes an extension 35 a that extends into the package 31. Two electrode portions 32 are formed on the extension portion 35a. The fixed electrode 5 and the fixed electrode 6 of the crystal vibrating piece 30 are fixed to the electrode portion 32 using a conductive paste or the like, and are brought into conduction. Here, as the conductive adhesive 43, one obtained by adding conductive particles such as silver particles to a binder component made of a predetermined synthetic resin can be used.

  The first substrate 34, the second substrate 35, and the third substrate 36 are formed of an insulating material, and ceramic is suitable. In particular, a material having a thermal expansion coefficient that matches or very close to that of the crystal vibrating piece 30 and the lid 37 is selected as a preferable material. In this embodiment, for example, a ceramic green sheet is used. Yes. The green sheet is obtained, for example, by dispersing a ceramic powder in a predetermined solution, forming a kneaded product formed by adding a binder into a sheet-like long tape shape, and cutting it into a predetermined length Is.

  The first substrate 34, the second substrate 35, and the third substrate 36 can be formed by laminating and sintering green sheets molded into the illustrated shape. In this case, the first substrate 34 is a substrate that constitutes the bottom of the package 31, and the second substrate 35 and the third substrate 36 that are stacked on the first substrate 34 have the above-described green sheet as a plate shape, and the internal material is removed. As a frame shape, the internal space S of FIG. 10 is formed, and the crystal vibrating piece 30 is accommodated using the internal space S. A lid 37 made of a metal such as ceramic, glass or Kovar is bonded to the package 31 via a bonding material such as a Kovar ring or a sealing material 47. Thereby, the package 31 is hermetically sealed.

On the first substrate 34, for example, after forming a required conductive pattern using a conductive paste such as silver or palladium or a conductive paste such as tungsten metallization, the first substrate 34, the second substrate 35, and the first substrate 34 are formed. After sintering with the three substrates 36, nickel, gold, silver, or the like is sequentially plated to form the electrode portion 32 described above.
As shown in FIG. 10, the electrode part 32 is connected to at least two mounting terminals 41 exposed on the bottom surface of the package 31 by a conductive pattern (not shown). The conductive pattern for connecting the electrode part 32 and the mounting terminal 41 may be formed on the surface of a castellation (not shown) used when the package 31 is formed, and the outer surface of the package 31 may be drawn around. Alternatively, the first substrate 34 and the second substrate 35 may be connected by a conductive through hole or the like.

  By applying an AC voltage between the two mounting terminals 41, an AC current flows between the fixed electrode 5 and the fixed electrode 6 (see FIG. 4). Thereby, the quartz crystal vibrating piece 30 performs bending vibration indicated by the solid line arrow and the two-dot chain line arrow in the above-described embodiment.

  Therefore, according to the fifth embodiment, it is possible to obtain a crystal resonator that exhibits the same effect as the above-described embodiment.

(Sixth embodiment)
Hereinafter, a crystal oscillator will be described as an example of the piezoelectric device of the sixth embodiment.

  The crystal oscillator of the sixth embodiment is a crystal oscillator using the crystal resonator element of the first to fourth embodiments. For this reason, since the crystal vibrating piece used for the crystal oscillator of the sixth embodiment has the same configuration as the crystal vibrating piece of the first to fourth embodiments, the same reference numerals are given and description of the configuration is omitted. Below, it demonstrates using the crystal vibrating piece 30 of 3rd Embodiment. The fifth embodiment differs from the sixth embodiment in that the crystal oscillator of the sixth embodiment includes an IC chip that includes a drive circuit that drives the crystal resonator to the crystal resonator shown in the fifth embodiment. It is a point with.

  As shown in FIG. 11, an internal connection terminal 89 made of gold (Au) or the like is formed on the upper surface of the first substrate 34 forming the package 31. The IC chip 87 is fixed to the upper surface of the first substrate 34 forming the package 31 using an adhesive or the like. An IC connection pad 82 made of Au or the like is formed on the upper surface of the IC chip 87. The IC connection pad 82 is connected to the internal connection terminal 89 by a metal wire 88. The internal connection terminal 89 is connected to the mounting terminal 41 formed on the lower surface of the first substrate 34 outside the package 31 via an internal wiring. Note that the connection method between the IC chip 87 and the internal connection terminals 89 is not limited to the method using the metal wire 88 but may be the connection method using flip chip mounting.

  Therefore, according to the sixth embodiment, it is possible to obtain a crystal oscillator that exhibits the same effect as the above-described embodiment.

  In the sixth embodiment, a crystal oscillator has been described as an example of a piezoelectric device. However, the present invention is not limited to this, and a gyro sensor having a detection circuit in an IC chip 87 may be used.

  In addition, the deformation | transformation in the range which can solve at least one part of the said subject, improvement, etc. are contained in above-mentioned embodiment.

  For example, in the above description, the excitation electrode 3 is connected to the fixed electrode 5 and the excitation electrode 4 is connected to the fixed electrode 6. However, the present invention is not limited to this, and the excitation electrode 4 is connected to the fixed electrode 5. The excitation electrode 3 may be connected to the fixed electrode 6.

The material of the bending vibration piece is not limited to quartz, but lithium tantalate (LiTaO ₃ ), lithium tetraborate (Li ₂ B ₄ O ₇ ), lithium niobate (LiNbO ₃ ), lead zirconate titanate (PZT). ), A piezoelectric body such as zinc oxide (ZnO) or aluminum nitride (AlN), or a semiconductor such as silicon.

Schematic which shows the quartz crystal vibrating piece of 1st Embodiment. The schematic sectional drawing of FIG. Schematic which shows the quartz crystal vibrating piece of 2nd Embodiment. FIG. 4 is a schematic sectional view of FIG. 3. Schematic which shows the quartz crystal vibrating piece of 3rd Embodiment. FIG. 6 is a schematic sectional view of FIG. 5. Schematic which shows the quartz crystal vibrating piece of 4th Embodiment. FIG. 8 is a schematic sectional view of FIG. 7. The schematic plan view of the crystal oscillator which exposed the internal structure except the cover body of 5th Embodiment. XX schematic sectional drawing of FIG. FIG. 10 is a schematic cross-sectional view showing a crystal oscillator according to a sixth embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Bending vibration part, 2 ... Base part, 3, 4 ... Excitation electrode, 5, 6 ... Fixed electrode, 10 ... Quartz vibration piece, 11 ... 1st surface, 12 ... 2nd surface, 13 ... 3rd surface, 14 ... 4th surface, 16 ... slit part, 20 ... crystal vibrating piece, 30 ... crystal vibrating piece, 40 ... crystal vibrating piece.

Claims (4)

The base,
A bending vibration part formed extending from the base and bending and vibrating,
The bending vibration parts are arranged opposite to each other, and a first surface and a second surface that alternately expand and compress by bending vibration;
A through hole penetrating between the first surface and the second surface;
The bending vibration piece, wherein the through hole is formed to extend from the bending vibration part to the base part. The bending vibration piece according to claim 1,
Of the end portions of the through-holes, all the end portions provided in the bending vibration portion are disposed on the base side from a position half the length of the bending vibration portion in the extending direction. Bending vibration piece. A bending vibrator using the bending vibration piece according to claim 1 or 2,
The bending vibration piece;
A package for storing the bending vibration piece,
A bending vibrator, wherein the bending vibration piece is hermetically sealed in the package. A piezoelectric device using the bending vibration piece according to claim 1 or 2,
The bending vibration piece;
An IC chip for driving the bending vibrator;
A package containing the bending vibration piece and the IC chip;
A piezoelectric device, wherein the bending vibration piece and the IC chip are hermetically sealed in the package.

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