JP5774295B2 - Piezoelectric device - Google Patents

Description

  The present invention relates to a piezoelectric device used in electronic equipment and the like.

Conventional piezoelectric vibrators are mainly composed of, for example, an element mounting member, a tuning fork-type bent quartz crystal vibration element, and a lid.
The element mounting member includes a substrate part and a frame part.
In this element mounting member, a frame portion is provided on one main surface of the substrate portion to form a recessed space.
A pair of piezoelectric vibration element mounting pads are provided on one main surface of the substrate portion exposed in the concave space, and a tuning fork type crystal vibration element is mounted thereon.
The substrate portion has a laminated structure, and an inner layer of the substrate portion is provided with a wiring pattern (not shown). With this wiring pattern, the piezoelectric vibration element mounting pad is connected to an external connection electrode terminal provided on the other main surface of the substrate portion of the element mounting member.
The top surface of the frame portion of the element mounting member that surrounds the tuning fork-type bent quartz crystal vibration element is covered with and joined to a metal lid. Thereby, the recessed space is hermetically sealed.

Such a tuning-fork type bending crystal resonator element includes a base portion and two flat plate-shaped vibrating arm portions extending in the same direction from the side surface of the base portion.
On the surface of the base and the vibrating arm, a connection electrode, an excitation electrode, and a frequency adjusting metal film that are electrically connected to the piezoelectric vibration element mounting pad of the element mounting member are formed.
This tuning fork-type bending crystal resonator element is cantilevered by fixing a connection electrode to a piezoelectric resonator element mounting pad with a conductive adhesive. In the vibrating arm portion at this time, an end portion facing the side opposite to the base portion is a tip portion (see, for example, Patent Document 1).
In addition, since the frequency fluctuates when the tip portion contacts the bottom surface in the recess space of the element mounting member, in the conventional piezoelectric device, bumps are formed on the piezoelectric vibration element mounting pad on the bottom surface in the recess space of the element mounting member. A formed structure has been proposed (see, for example, Patent Document 2).
The bumps support the tuning fork-type bending quartz crystal vibration element, and the principle of the lever works, so that the tip of the vibrating arm portion of the tuning-fork type bending quartz crystal vibration element can be floated so as not to contact the bottom surface in the recess space.

JP 2008-252800 A JP 2001-102891 A

  However, when the conventional piezoelectric device is mounted with a tuning fork type quartz crystal resonator element, when the tip of the vibrating arm portion of the tuning fork type crystal resonator element comes into contact with the substrate portion exposed in the recessed space of the element mounting member, Since the vibration is inhibited, there is a problem that the oscillation frequency of the piezoelectric device fluctuates.

  This invention is made | formed in view of the said subject, and makes it a subject to provide the piezoelectric device with which the oscillation frequency of a tuning fork type bending quartz crystal vibration element does not fluctuate.

The piezoelectric device of the present invention includes a substrate portion, an element mounting member in which a frame portion is provided on one main surface of the substrate portion to form a recessed space, and one of the substrate portions being exposed in the recessed space. Mounted on a pair of piezoelectric vibration element mounting pads provided on the main surface of the base, and a base, two vibrating arms extending in the same direction from the side of the base, and the two vibrating arms A tuning fork-type bent quartz crystal vibration element provided with a balance arm portion extending in the same direction as the vibrating arm portion from the side surface of the base portion positioned between, and a lid for hermetically sealing the concave space A first bump provided on the piezoelectric vibration element mounting pad, and a second bump provided on the element mounting member, wherein the balance arm portion extends in the extending direction of the balance arm portion. Is formed shorter than the length of the vibrating arm in the extending direction, The second bump is provided at a position facing the balance arm, and the tuning fork-type bending quartz crystal vibration element is in contact with the second bump while the balance arm is insulated. It is arrange | positioned in the said recessed space.

  Further, the second bump is made of metal, and the tip of the second bump is arranged so as to come into contact with a portion where the electrode of the balance arm is not provided. Is.

  In addition, the second bump is provided by an insulating resin.

  According to the piezoelectric device of the present invention, the piezoelectric device includes a first bump provided on the piezoelectric vibration element mounting pad and a second bump provided on the element mounting member. The first bump comes into contact with the base portion of the tuning fork type bending quartz crystal vibration element and the second bump comes into contact with the balance arm portion. It is possible to reduce the contact of the tip of the vibrating arm portion with the substrate portion exposed in the recessed space of the element mounting member. Thereby, the piezoelectric device of the present invention can reduce the fluctuation of the oscillation frequency.

  Further, the second bump is provided with a metal, and the tip of the second bump is arranged so as to be in contact with a portion where the electrode of the balance arm is not provided. It is possible to reduce a short circuit between the excitation electrodes provided in the pair of vibrating arms.

  In addition, since the second bump is provided by an insulating resin, the vibrating arm portion is lowered while preventing the excitation electrodes provided on the two pairs of vibrating arm portions from being short-circuited. Can be prevented.

1 is an exploded perspective view showing a piezoelectric device according to a first embodiment of the present invention. It is AA sectional drawing of FIG. (A) is a top view which shows the element mounting member of the state which mounted the tuning fork type piezoelectric vibration element which comprises the piezoelectric device which concerns on the 1st Embodiment of this invention, (b) is 1st of this invention. It is a top view which shows the element mounting member which comprises the piezoelectric device which concerns on this embodiment. It is the fragmentary sectional view which expanded the 2nd bump of the piezoelectric device concerning a 1st embodiment of the present invention. It is sectional drawing which shows the piezoelectric device which concerns on the 2nd Embodiment of this invention.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. A case where quartz is used for the piezoelectric vibration element will be described.

1st Embodiment demonstrates the piezoelectric vibrator which is one of the examples of a piezoelectric device.
As shown in FIGS. 1 and 2, the piezoelectric vibrator 200 mainly includes an element mounting member 210, a tuning fork type bending piezoelectric vibration element 100, and a lid body 230. In the piezoelectric vibrator 200, the tuning fork type bending crystal resonator element 100 is mounted in the first recessed space K 1 formed in the element mounting member 210. The first recessed space K1 is hermetically sealed by the lid 230.

(Tuning fork type crystal vibrating element)
As shown in FIGS. 1 to 3, the tuning-fork type bending crystal resonator element 100 includes a crystal piece 110, excitation electrodes 121a, 121b, 122a and 122b provided on the surface of the crystal piece 110, and a connection electrode 123a. And 123b, frequency adjusting metal films 124a and 124b, and conductive wiring patterns 125 and 126.

As shown in FIGS. 1 and 3A, the crystal piece 110 includes a base portion 111, a vibrating arm portion 112, and a balancing arm portion 113, and the vibrating arm portion 112 includes the first vibrating arm portion 112a and the second vibrating arm portion 112a. The vibrating arm portion 112b.
When the base 111 is an orthogonal coordinate system in which the electrical axis is the X axis, the mechanical axis is the Y axis, and the optical axis is the Z axis as the crystal axis direction, the base 111 is within a range of −5 ° to + 5 ° around the X axis This is a flat plate having a substantially rectangular shape in a plan view in which the direction of the rotated Z ′ axis is the thickness direction.
The first vibrating arm portion 112a and the second vibrating arm portion 112b extend from one side of the base portion 111 in parallel to the Y′-axis direction.
Further, the balance arm 113 extends in parallel with the Y ′ axis from one side of the base 111 located between the first vibrating arm 112 a and the second vibrating arm 112 b.
The crystal piece 110 has a tuning fork shape in which the base portion 111, the vibrating arm portions 112, and the balance arm portion 113 are integrally formed, and is manufactured by a photolithography technique and a chemical etching technique.

The crystal piece 110a includes a base portion 111 having a flat plate shape, a pair of vibrating arm portions 112 extending from one side of the base portion 111 in the same direction, and extending from one side of the base portion 111 in the same direction. The balance arm 113 is provided between the pair of vibrating arm portions 112.
In addition, since the vibration arm part 112 is a pair of two, it demonstrates as the 1st vibration arm part 112a and the 2nd vibration arm part 112b.

Moreover, as shown in FIG. 1, the excitation electrode 122a is provided on the front and back main surfaces of the first vibrating arm portion 112a. The excitation electrode 122b is provided on both opposing side surfaces of the first vibrating arm portion 112a.
The frequency adjusting metal film 124a is provided on the front main surface and the front end of the side surface of the first vibrating arm portion 112a.
The connection electrode 123 a is provided on the front and back main surfaces of the base 111 on the first vibrating arm portion 112 a side of the base 111.

As shown in FIG. 1, the excitation electrode 121a is provided on the front and back main surfaces of the second vibrating arm portion 112b. The excitation electrode 121b is provided on both opposite side surfaces of the second vibrating arm portion 112b.
The frequency adjusting metal film 124b is provided on the front main surface and the front end portions of both side surfaces of the second vibrating arm portion 112b.
The connection electrode 123 b is provided on the front and back main surfaces of the base 111 on the second vibrating arm 112 b side of the base 111.

  The tuning-fork type bending crystal resonator element 100 can adjust the vibration frequency value to a desired value by increasing / decreasing the amount of the metal constituting the frequency adjusting metal films 124a and 124b.

As shown in FIG. 1, the excitation electrodes 121a and 122b, the frequency adjusting metal film 124a, and the connection electrode 123a are electrically connected by, for example, a conductive wiring pattern 125 provided on the surface of the crystal base plate 110. ing.
The connection electrode 123 a is electrically connected to the excitation electrode 121 a through a conductive wiring pattern 125 provided on the base 111. The connection electrode 123a is electrically connected to the excitation electrode 122b.

In addition, as shown in FIG. 1, the excitation electrodes 121b and 122a, the frequency adjusting metal film 124b, and the connection electrode 123b are electrically connected by, for example, a conductive wiring pattern 126 provided on the surface of the crystal piece 110. doing.
The connection electrode 123b is electrically connected to the excitation electrode 121b and the frequency adjusting metal film 124b. In addition, the conductive wiring pattern 126 provided on the front main surface of the base 111 is electrically connected to the excitation electrode 122a and the excitation electrode 121b.

  The excitation electrodes 121a, 121b, 122a and 122b, the connection electrodes 123a and 123b, the frequency adjusting metal films 124a and 124b, and the conductive wiring patterns 125 and 126 are, for example, a Cr layer as a base metal. , And an Au layer provided on the base metal.

The balance arm 113 extends in the same direction from one side of the base 111 and is provided between the pair of vibrating arms 112.
The balance arm 113 is a relay point for electrically connecting the excitation electrodes 121a, 121b, 122a, and 122b. Further, the balance arm portion 113 plays a role of balancing the positions of the first vibrating arm portion 112a and the second vibrating arm portion 112b.

  When this tuning fork type bending crystal resonator element 100 is vibrated, an alternating voltage is applied to the connection electrodes 123a and 123b. When an electrical state after application is instantaneously captured, the excitation electrode 121b of the second vibrating arm portion 112b has a + (plus) potential, the excitation electrode 121a has a-(minus) potential, and changes from + to-. An electric field is generated. On the other hand, the excitation electrode of the first vibrating arm portion 112a at this time has a polarity opposite to the polarity generated in the exciting electrode of the second vibrating arm portion 112b. These applied electric fields cause an expansion / contraction phenomenon in the first vibrating arm portion 112a and the second vibrating arm portion 112b, and a bending vibration having a resonance frequency set in each vibrating arm portion 112 is obtained.

As shown in FIGS. 1-2, the element mounting member 210 is mainly comprised by the board | substrate part 210a and the frame part 210b (refer FIG. 2).
In the element mounting member 210, a frame portion 210b is provided on one main surface of the substrate portion 210a to form a recessed space K1.
An annular sealing conductor pattern 212 is formed on the entire periphery of the opening-side top surface of the frame portion 210b that surrounds the recessed space K1 of the element mounting member 210.
Two pairs of piezoelectric vibration element mounting pads 211 are provided on one main surface of the substrate portion 110a exposed in the recessed space K1.
Two pairs of first bumps BP1 are provided on the principal surface of the piezoelectric vibration element mounting pad 211, respectively.
A second bump BP2 is provided on the main surface of the element mounting member 210.
External connection electrode terminals G are provided at both ends of the other main surface of the substrate portion 210 a of the element mounting member 210.
A wiring pattern (not shown) or the like is provided on the inner layer of the substrate part 210a, and a predetermined piezoelectric vibration element mounting pad 211 and an external connection electrode terminal G are connected.

As shown in FIG. 3, the first bump BP <b> 1 is provided in a predetermined range on the main surface of the piezoelectric vibration element mounting pad 211.
The first bump BP <b> 1 is provided so as to be at the position of the base 111 of the tuning fork-type bending crystal resonator element 100. That is, the first bump BP1 is in contact with the base 111, and the tip of the vibrating arm portion 112 of the tuning fork-type bending crystal resonator element 100 is lifted with the first bump BP1 as a fulcrum.
Similar to the piezoelectric vibration element mounting pad 211, the first bump BP1 is provided, for example, by applying nickel (Ni) plating, gold (Au) plating, or the like to a metallization such as tungsten (W).
The vertical width of the first bump BP1 shown in FIG. 3 is, for example, 100 to 200 μm, and the horizontal width of the first bump BP1 is, for example, 200 to 300 μm.

Further, as shown in FIG. 3, the conductive adhesive DS is applied to the main surface of the piezoelectric vibration element mounting pad 211 so as not to be applied to the first bump BP1. That is, the conductive adhesive DS is applied to the position of the base 111 of the tuning fork-type bending crystal resonator element 100.
The distance between the conductive adhesive DS and the first bump BP1 is, for example, 100 to 200 μm.
Since the conductive adhesive DS is applied to the piezoelectric vibration element mounting pad 211 in this way, the thickness of the conductive adhesive DS can be increased even if the tuning fork type bending crystal vibration element 100 is mounted on the conductive adhesive DS. Can be secured.
The thickness of the conductive adhesive DS is the same as the thickness of the first bump BP1. That is, the thickness of the conductive adhesive DS at this time is 15 μm to 30 μm in the state where the tuning fork type bending quartz crystal vibration element 100 is mounted.

As shown in FIG. 3, the second bump BP <b> 2 is provided on the main surface of the element mounting member 210 at a position facing the balance arm 113 of the tuning fork type bending crystal resonator element 100. That is, the second bump BP <b> 2 is provided at a position in contact with the balance arm portion 113 of the tuning fork type bending crystal resonator element 100.
Further, the second bump BP2 is in contact with the balance arm 113, and the tip of the vibrating arm 112 of the tuning fork type bending crystal resonator 100 is exposed in the first concave space K1 of the element mounting member 210. Contact with the substrate portion 210a can be prevented.
The second bump BP2 is provided by a metal such as tungsten (W), for example.
Further, as shown in FIG. 4, when the second bump BP2 is made of metal, the tip of the second bump BP2 is in contact with a portion where the electrode of the balance arm 113 is not provided. Is arranged. By doing in this way, it can reduce that the electrodes for excitation provided in two pairs of vibrating arms 112 are short-circuited.
Further, the vertical width of the second bump BP2 shown in FIG. 3 is, for example, 150 to 350 μm, and the horizontal width of the second bump BP2 is, for example, 50 to 250 μm.

Note that the second bump BP2 may be provided with an insulating resin made of, for example, an epoxy resin, a polyimide resin, or the like.
As described above, the second bump BP2 is provided by the insulating resin, thereby preventing the excitation electrodes provided in the two pairs of vibrating arms 112 from being short-circuited, and the vibrating arm. It is possible to prevent the portion 112 from falling.

As shown in FIGS. 1 and 2, the lid 230 is disposed and joined on the sealing conductor pattern 212 of the element mounting member 210 so as to cover the opening of the first recessed space K <b> 1. The lid 230 is provided with a sealing member 231 at a location facing the sealing conductor pattern 212.
Further, such a sealing member 231 can relieve unevenness on the surface of the sealing conductor pattern 212 and prevent deterioration in airtightness.

  Further, the lid 230 disposed on the element mounting member 210 is manufactured by adopting a conventionally known metal processing method and shaping a metal such as 42 alloy into a predetermined shape. A nickel (Ni) layer is formed on the upper surface of the lid 230, and gold tin (Au—Sn) which is a sealing member 231 at least on the upper surface of the nickel (Ni) layer at a position facing the sealing conductor pattern 212. ) Layer is formed. The thickness of the gold tin (Au—Sn) layer is 10 μm to 40 μm. For example, the component ratio is 80% gold and 20% tin.

  The conductive adhesive DS contains conductive powder as a conductive filler in a binder such as silicone resin. Examples of the conductive powder include aluminum (Al), molybdenum (Mo), tungsten ( W), platinum (Pt), palladium (Pd), silver (Ag), titanium (Ti), nickel (Ni), nickel iron (NiFe), or any combination thereof is used. Yes.

  In addition, when the element mounting member 210 is made of alumina ceramic, a piezoelectric vibration element mounting pad 211 and a seal are formed on the surface of a ceramic green sheet obtained by adding and mixing an appropriate organic solvent or the like to a predetermined ceramic material powder. Conductor paste serving as a conductor pattern 212, electrode terminals G for external connection, etc., and a conductor serving as a via conductor in a through hole (not shown) previously punched by punching a ceramic green sheet The paste is applied by conventionally known screen printing, and a plurality of the pastes are laminated and press-molded, and then fired at a high temperature.

  According to the piezoelectric device 200 according to the first embodiment of the present invention, the first bump BP1 provided on the piezoelectric vibration element mounting pad 211 and the second bump BP2 provided on the element mounting member 210 are provided. And the second bump BP2 is provided at a position facing the balance arm 113, so that the first bump BP1 comes into contact with the base 111 of the tuning fork-type bending crystal resonator element 100, and the second bump When BP2 comes into contact with the balance arm 113, the tip of the vibrating arm 112 of the tuning fork-type bent quartz crystal vibrating element 100 comes into contact with the substrate 210a exposed in the first concave space K1 of the element mounting member 210. Can be reduced. Thereby, the piezoelectric device 200 of the present invention can reduce the fluctuation of the oscillation frequency.

(Second Embodiment)
In the second embodiment, a piezoelectric oscillator which is an example of a piezoelectric device will be described. In addition, the illustrated dimensions are partially exaggerated.
The piezoelectric device 300 according to the second embodiment of the present invention includes an integrated circuit element 340 mounted in the second recessed space K2 provided by the substrate portion 310a and the second frame portion 310c of the element mounting member 310. And is different from the first embodiment.

  As shown in FIG. 5, the piezoelectric oscillator 300 according to the third embodiment of the present invention is mainly configured by an element mounting member 310, a tuning fork-type bending crystal resonator element 100, a lid body 230, and an integrated circuit element 340. . In the piezoelectric oscillator 300, the tuning fork type bending crystal resonator element 100 is mounted in the first recessed space K1 formed in the element mounting member 310, and the integrated circuit element 340 is mounted in the second recessed space K2. It is installed. The first recessed space K1 is hermetically sealed by the lid 230.

As shown in FIG. 5, the integrated circuit element 340 is provided with an oscillation circuit or the like for generating an oscillation output from the tuning-fork type bending crystal resonator element 100 on the circuit forming surface, and an output signal generated by this oscillation circuit. Is output to the outside of the piezoelectric oscillator 300 via the external connection electrode terminal G, and is used as a reference signal such as a clock signal, for example.
Further, the integrated circuit element 340 is applied with a control voltage according to the ambient temperature to the variable capacitance element to compensate for fluctuations in the oscillation frequency of the oscillation circuit due to temperature changes. A compensation circuit unit is provided, and a temperature sensor is connected to the cubic function generation circuit.
This temperature sensor is configured to output a temperature data signal (voltage value) generated based on the detected temperature and a voltage value applied to the temperature sensor to a cubic function generation circuit.
The integrated circuit element 340 is mounted on an integrated circuit element mounting pad 314 formed on the substrate portion 310a exposed in the second recessed space K2 of the element mounting member 310 via a conductive bonding material such as solder.

As shown in FIG. 5, the element mounting member 310 is mainly composed of a substrate part 310a and frame parts 310b and 310c.
In the element mounting member 310, a frame portion 310b is provided on one main surface of the substrate portion 310a to form a first recess space K1. In addition, a frame part 310c is provided on the other main surface of the element mounting member 310 to form a second recess space K2.
An annular sealing conductor pattern 312 is formed on the entire circumference of the opening-side top surface of the frame portion 310b that surrounds the first recess space K1 of the element mounting member 310.
A pair of piezoelectric vibration element mounting pads 311 are provided on one main surface of the substrate portion 310a while being exposed in the first recess space K1.
As shown in FIG. 5, in the element mounting member 310, a second recessed space K2 is formed by the other main surface of the substrate portion 310a and the frame portion 210c.
A wiring pattern (not shown) or the like is provided on the inner layer of the substrate portion 310a.
A plurality of integrated circuit element mounting pads 313 and two pairs of piezoelectric vibration element measurement pads (not shown) are formed on the other main surface of the substrate portion 310a while being exposed in the second recess space K2. Yes.
External connection electrode terminals G are provided at the four corners of the other main surface of the frame portion 310 c of the element mounting member 310.

The first bump BP1 is provided in a predetermined range on the main surface of the piezoelectric vibration element mounting pad 311 as in the first embodiment.
The first bump BP <b> 1 is provided so as to be at the position of the base 111 of the tuning fork-type bending crystal resonator element 100. That is, the first bump BP1 is in contact with the base 111, and the tip of the vibrating arm portion 112 of the tuning fork-type bending quartz crystal vibrating element 100 is floated using this as a fulcrum.

The second bump BP <b> 2 is provided on the main surface of the element mounting member 310 at a position facing the balance arm 113 of the tuning fork-type bending crystal resonator element 100. That is, the second bump BP <b> 2 is provided at a position in contact with the balance arm 313 of the tuning fork type bending crystal resonator element 100.
Further, the second bump BP2 is in contact with the balance arm 113, and the tip of the vibrating arm 112 of the tuning fork type bending crystal resonator 100 is exposed in the first recess space K1 of the element mounting member 310. Contact with the substrate portion 310a can be prevented.
Similar to the first bump BP1, the second bump BP2 is provided, for example, by applying nickel (Ni) plating, gold (Au) plating, or the like to a metallization such as tungsten (W).
Further, when the second bump BP2 is made of metal, the tip of the second bump BP2 is disposed so as to come into contact with a portion where the electrode of the balance arm 113 is not provided. By doing in this way, it can reduce that the electrodes for excitation provided in two pairs of vibrating arms 112 are short-circuited.

Note that the second bump BP2 may be provided with an insulating resin made of, for example, an epoxy resin, a polyimide resin, or the like.
As described above, the second bump BP2 is provided by the insulating resin, thereby preventing the excitation electrodes provided in the two pairs of vibrating arms 112 from being short-circuited, and the vibrating arm. It is possible to prevent the portion 112 from falling.

Similarly to the first embodiment, the lid 230 is disposed and joined on the sealing conductor pattern 312 of the element mounting member 310 so as to cover the opening of the first recessed space K1. The lid 230 is provided with a sealing member 231 at a location opposite to the sealing conductor pattern 312.
As in the first embodiment, the conductive adhesive DS is applied to the main surface of the piezoelectric vibration element mounting pad 311 so as not to cover the first bump BP1. That is, the conductive adhesive DS is applied to the position of the first base portion 321a of the tuning fork type bending crystal resonator element 100.

In addition, this invention is not limited to the said embodiment, A various change, improvement, etc. are possible in the range which does not deviate from the summary of this invention.
For example, in the above-described embodiment, the case where quartz is used as the piezoelectric material constituting the piezoelectric vibration element has been described. However, as other piezoelectric materials, lithium niobate, lithium tantalate, or piezoelectric ceramics is used as the piezoelectric material. The piezoelectric vibration element may be used.

DESCRIPTION OF SYMBOLS 100 ... Tuning fork type bending crystal vibrating element 110 ... Crystal base plate 111 ... Base 112a, 112b ... Vibration arm 113 ... Balance arm 121a, 121b, 122a, 122b ... Excitation Electrodes 123a, 123b ... Connecting electrodes 124a, 124b ... Frequency adjusting electrodes 210, 310 ... Element mounting members 210a, 310a ... Substrate portions 210b, 310b ... Frame portions 211, 311 ··· Piezoelectric vibration element mounting pads 212 and 312 ··· Sealing conductor pattern 313 ··· Integrated circuit element mounting pad 230 ··· Lid 350 · · · ..First recess space (recess space)
K2: Second recess space G: External connection electrode terminal BP1: First bump BP2: Second bump DS: Conductive adhesive

Claims (3)

A substrate portion, and an element mounting member in which a frame portion is provided on one main surface of the substrate portion to form a recess space;
A pair of piezoelectric vibration element mounting pads provided on one main surface of the substrate portion while being exposed in the recess space, and mounted in the same direction from the base portion and the side surface of the base portion. A tuning fork-type bending quartz crystal vibration element comprising: a vibrating arm; and a balance arm extending in the same direction as the vibrating arm from a side surface of the base located between the two vibrating arms. ,
A lid for hermetically sealing the recessed space;
A first bump provided on the piezoelectric vibration element mounting pad;
A second bump provided on the element mounting member,
The balance arm portion is formed such that the length of the balance arm portion in the extending direction is shorter than the length of the vibrating arm portion in the extending direction;
The second bump is provided at a position facing the balance arm,
The piezoelectric fork device is characterized in that the tuning fork-type bending crystal resonator element is disposed in the recess space so that the balance arm portion is in contact with the second bump while being insulated.   The second bump is provided with a metal, and the tip of the second bump is arranged so as to be in contact with a portion where the electrode of the balance arm is not provided. 1. The piezoelectric device according to 1.   The piezoelectric device according to claim 1, wherein the second bump is provided by an insulating resin.

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