JP2009152989A - Piezoelectric vibration chip and piezoelectric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piezoelectric vibration chip or piezoelectric device which hardly causes a discharge so as to avoid damaging an electronic element in the piezoelectric vibration chip or piezoelectric device owing to electrostatic discharge reaction. <P>SOLUTION: The piezoelectric vibration chip includes: a base formed with first and second base electrodes; a first vibration arm portion and a second vibration arm portion protruding from the base; first and second excitation electrodes formed at the first and second vibration arm portions; and a first connection electrode portion connecting the first base electrode and first excitation electrode to each other by an electrode formed in a curved-line shape, and a second connection electrode portion connecting the second base electrode and second excitation electrode to each other by an electrode formed in a curved-line shape. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of a piezoelectric vibrating piece and a piezoelectric device in which a piezoelectric vibrating piece is accommodated in a package.

  A piezoelectric device using a piezoelectric vibrating piece is widely used as a clock source for a clock, a computer, a mobile phone or the like, or for measuring an angular velocity. In recent years, the degree of integration of piezoelectric components has increased, and accordingly, further downsizing of piezoelectric devices has been required. The miniaturization of piezoelectric devices has also weakened electrostatic resistance. As a miniaturized piezoelectric vibrating piece, for example, Patent Literature 1 discloses a tuning fork type piezoelectric vibrating piece.

  A piezoelectric device must prevent the device from being destroyed by static electricity stored in the human body. For this reason, the ESD test is an HBM (Human Body Model) test. In addition, MM (machine model) tests are performed so that the piezoelectric device is not destroyed by static electricity accumulated in the assembly device of the piezoelectric device. Recently, due to further miniaturization of the piezoelectric vibrating piece or the piezoelectric device, rapid charge transfer occurs when the charge charged to the capacitance inherent to the device approaches or contacts a conductor having a different potential potential. (Charged device model) Tests are also being conducted.

  The ESD withstand voltage of the piezoelectric device using the piezoelectric vibrating piece is about 500 V, which is lower than that of other piezoelectric components. For this reason, it is required to improve the ESD withstand voltage of the piezoelectric vibrating piece or the piezoelectric device. In particular, with the miniaturization of the piezoelectric vibrating piece or the piezoelectric device, the pattern is often destroyed by electrostatic discharge in a thin electrode pattern.

FIG. 7 shows an example of a tuning fork-type piezoelectric vibrating piece 120 as disclosed in Patent Document 1. The tuning-fork type piezoelectric vibrating piece 120 includes, for example, a small vibrator having a resonance frequency of 32.768 kHz, and finally. Is used by being incorporated in precision equipment such as a watch.
The tuning fork type piezoelectric vibrating piece 120 is configured such that the left and right arm portions 121 vibrate when an electric current is applied from the outside. Specifically, the groove electrode 123d and the groove electrode 125d are formed in the groove 131 of the arm 121 shown in FIG. On the other hand, the side electrode 123c and the side electrode 125c are formed on both side surfaces where the grooves 131 are not provided. When a current is applied, an electric field is generated between the groove electrode 123d and the groove electrode 125d and the side electrode 123c and the side electrode 125c, so that the arm portion 121 vibrates.

Base electrodes 123a and 125a are formed on the base 129 of the tuning fork type piezoelectric vibrating piece 120, and current is supplied to the base electrodes 123a and 125a from the outside. In order to supply current from the base electrodes 123a and 125a to the groove electrode 123d and the groove electrode 125d, the side electrode 123c, and the side electrode 125c, connection electrodes 123b and 125b are formed.
The adjacent connection electrode 123b and connection electrode 125b have a very narrow width, for example, only about 0.01 mm to 0.03 mm. In particular, a short circuit due to discharge occurs in a region DC surrounded by a circle.
JP 2002-261575 A

  The electrostatic charge of the piezoelectric vibrating piece causes an electrostatic discharge reaction through particles in the atmosphere through the discharge protrusion. For this reason, it is conceivable that the short circuit due to the discharge is likely to occur in the region DC because a corner portion of 90 degrees exists in a part of the connection electrode 123b or the connection electrode 125b.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a piezoelectric vibrating piece or a piezoelectric device in which discharge is unlikely to occur in order to avoid damage to an electronic element in the piezoelectric vibrating piece or piezoelectric device due to an electrostatic discharge reaction.

A piezoelectric vibrating piece according to a first aspect includes a base portion on which first and second base electrodes are formed, a first vibrating arm portion and a second vibrating arm portion protruding from the base portion, and first and second vibrating arms. First and second excitation electrodes formed on the first portion, a first connection electrode portion connecting the first base electrode and the first excitation electrode with a curved electrode, a second base electrode and a second base electrode A second connection electrode portion that connects the excitation electrode with a curved electrode.
According to the configuration of the first aspect, the first connection electrode portion and the second connection electrode portion are formed in a curved shape. For this reason, since there is no corner in the first connection electrode portion and the second connection electrode portion, it is difficult for a discharge to occur between the adjacent first connection electrode portion and second connection electrode portion. Conventionally, as shown in FIG. 7 (a), a corner portion has been generated, so that a large proportion of discharge has occurred. That is, the present invention can reduce the occurrence of disconnection or short circuit.

The piezoelectric vibrating piece according to the second aspect is the first connection electrode in that the straight side of the first base electrode or the straight side of the first excitation electrode coincides with the curved side of the first connection electrode unit. The tangential direction of the curved side of the part coincides with the direction of the straight side.
According to the configuration of the second aspect, the tangent direction of the curve coincides with the direction of the straight side at a point where the straight side of the electrode contacts the curved side of the first connection electrode portion. For this reason, since the transition from the straight side to the curve can be made smoothly, no corner is generated at the contact point between the straight side and the curved side of the first connection electrode portion.

In the piezoelectric vibrating piece according to the third aspect, the sides where the first base electrode and the second base electrode face each other are formed in a curved shape.
In the piezoelectric vibrating piece according to the third aspect, when corners exist on opposite sides of the base electrode, discharge may occur. However, if the base electrode is configured with a curve, the probability of occurrence of discharge is reduced.

In the piezoelectric electrode piece according to the fourth aspect, one side of the first connection electrode portion is formed with a constant curvature, and the other side is formed with a different constant curvature.
When designing a curved electrode pattern on the piezoelectric vibrating piece according to the fourth aspect, it can be designed easily.

In the piezoelectric electrode piece according to the fifth aspect, one side of the first connection electrode portion and one side of the first base electrode are formed with the same curvature.
In the piezoelectric electrode piece according to the fifth aspect, since one side of the base electrode and one side of the connection electrode appearing at the base all have the same curvature, the portion where the predetermined curve and the curve contact each other may form a corner. Absent.

A piezoelectric device according to a sixth aspect includes the piezoelectric vibrating piece according to any one of the first to fifth aspects, a package that accommodates the piezoelectric vibrating piece, and a sealing portion that seals the package.
According to the structure of the 6th viewpoint, a piezoelectric device can be comprised using the piezoelectric vibrating piece with few discharges.

<Configuration of tuning fork type crystal vibrating piece 20>
FIG. 1A is a diagram showing an overall configuration of the tuning-fork type crystal vibrating piece 20, and FIG. 1B is a side view of FIG. FIG. 2 is a cross-sectional view taken along line C2-C2 of FIG.
The base material of the tuning fork type crystal vibrating piece 20 is formed of a crystal single crystal wafer 10 processed into a Z-cut. In order to obtain the required performance in a small size, as shown in FIG. 1A, a tuning fork type crystal vibrating piece 20 is divided into a bifurcated and parallel to a base 29 and upward from the base 29 in FIG. A pair of extending vibrating arms 21 is provided.

  The tuning fork type crystal vibrating piece 20 is a vibrating piece that transmits a signal at, for example, 32.768 KHz, and is an extremely small vibrating piece. The overall length is about 2.1 mm and the width is about 0.5 mm. Grooves 31 are formed on the front and back surfaces of the vibrating arm 21 of the tuning fork type crystal vibrating piece 20. Two groove portions 31 are formed on the surface of one vibrating arm 21, and two groove portions 31 are similarly formed on the back surface side of the vibrating arm 21. That is, four groove portions 31 are formed in the pair of vibrating arms 21. The depth of the groove 31 is about 35 to 45% of the thickness of the quartz single crystal wafer 10. The groove part 31 is provided in order to suppress an increase in the CI value.

The size of the tuning fork type crystal vibrating piece 20 is as follows.
The longitudinal length L2 of the base portion 29 of the tuning fork type crystal vibrating piece 20 is, for example, 0.58 mm to 0.64 mm. On the other hand, the longitudinal length L1 of the vibrating arm 21 and the vibrating arm 22 disposed so as to protrude from the base portion 29 is formed to be about 1.45 mm to 1.65 mm. Accordingly, the length of the base 29 with respect to the vibrating arm 21 is about 40 percent. The arm width W3 of the vibrating arm 21 is about 0.08 to 0.12 mm. The width of the groove 31 is about 0.07 mm to 0.1 mm, which is about 80% of the arm width W3 of the vibrating arm 21. The thickness D1 of the tuning fork type crystal vibrating piece 20 is about 0.08 mm to 0.12 mm. This is equivalent to the thickness of a quartz single crystal wafer.

The base portion 29 on the vibrating arm 21 side has a length (width) in the X direction of W1, and the base portion on the opposite side of the vibrating arm 21 has a length (width) in the X direction that is greater than the width W1. Wide width W2. The width W1 is about 75 to 90 percent of the width W2. For example, the width W1 is 0.42 mm and the width W2 is 0.50 mm. For this reason, the leakage vibration leaking from the groove portion 31 due to the vibration of the vibrating arm 21 is not easily transmitted to the connecting portion 28 side of the base portion 29.
The base portion 29 is formed with two connecting portions 28. The two connecting portions 28 are members that remain when the tuning fork type crystal vibrating piece 20 is cut from the crystal single crystal wafer. After the exposure process and the crystal etching process, several thousands of connection parts 28 are formed on one crystal single crystal wafer. A tuning fork type crystal vibrating piece 20 is connected.

  The base 29 of the tuning fork type crystal vibrating piece 20 is formed in a substantially plate shape as a whole. The length of the base 29 with respect to the vibrating arm 21 is about 36%. Two connecting portions 28 are provided on the base 29 of the tuning fork type crystal vibrating piece 20. The connecting portion 28 is a portion for connecting the crystal single crystal wafer 10 and the tuning fork type crystal vibrating piece 20 when the tuning fork shape shown in FIG. 1 is formed from the crystal single crystal wafer 10 by photolithography and wet etching.

<Electrode pattern>
A first electrode pattern 23 and a second electrode pattern 25 are formed on the vibrating arm 21 and the base 29 of the tuning fork type crystal vibrating piece 20. Both the first electrode pattern 23 and the second electrode pattern 25 have a structure in which a gold (Au) layer of 100 Å to 5000 Å is formed on a chromium (Cr) layer of 150 Å to 5000 Å. That is, when the first layer and the second layer are combined, the thickness of the electrode pattern is 250 Å to 10000 Å. Further, a tungsten (W) layer, a nickel (Ni) layer, a nickel tungsten layer, or a titanium (Ti) layer may be used instead of the chromium (Cr) layer, and silver instead of the gold (Au) layer. An (Ag) layer may be used. In some cases, an aluminum (Al) layer, a copper (Cu) layer, or a silicon (Si) layer is used.

  As shown in FIG. 1A, a first base electrode 23 a and a second base electrode 25 a are formed on the base 29 of the tuning fork type crystal vibrating piece 20, and the first groove is formed on the groove 31 of the vibrating arm 21. An electrode 23d and a second groove electrode 25d are formed, respectively. Further, as shown in FIG. 2, a second side electrode 25c and a first side electrode 23c are formed on both side surfaces of the left and right vibrating arms 21 in FIG.

  The first side electrode 23c and the second side electrode 25c are connected to the first base electrode 23a and the second base electrode 25a via the first connection electrode 23b and the second connection electrode 25b. As shown in FIG. 1A, the first base electrode 23a and the second base electrode 25a, and the first connection electrode 23b and the second connection electrode 25b have an electrode shape having no corners. For this reason, it is difficult for electric discharge to occur between the first base electrode 23a and the first connection electrode 23b and the second base electrode 25a and the second connection electrode 25b.

<Other electrode patterns>
FIG. 3A shows an electrode pattern in which the connection portions of the connection electrode, the side surface electrode, and the groove electrode coincide with each other, and FIG. Is shown.

  In the lower region LC of FIG. 3A, the side where the base electrode 23-2a and the base electrode 25-2a face each other is connected to one side of the connecting portion 28. In the connecting portion 28 depicted in (a), the electrode pattern has a straight side. The electrode pattern 23-2a and the electrode pattern 25-2a are formed so that the tangent at the end of the curve matches the linear side of the electrode pattern. That is, since the tangent direction of the curve coincides with the direction of the straight line at the point where the straight side and the curved side are in contact with each other, there is no corner portion in the portion, and the discharge is less likely to occur.

  Further, in the upper region LC of FIG. 3A, the connection electrode 23-2b and the connection electrode 25-2b are the first side electrode 23c and the second side electrode 25c, and the first groove electrode 23d and the second groove electrode. Connect to 25d. At this time, the first side surface electrode 23 c and the second side surface electrode 25 c, and the first groove electrode 23 d and the second groove electrode 25 d are formed linearly on the vibrating arm 21. For this reason, the side of the straight line and the side of the curve coincide with each other, and the discharge is less likely to occur.

  In FIG. 3B, the sides where the base electrode 23-3a and the base electrode 25-3a face each other are formed with sides having a certain curvature from the center, including the connection electrode 23-3b and the connection electrode 25-3b. Has been. Further, the connection electrode 23-2b and the connection electrode 25-2b are also formed with sides having a certain curvature from the center. The side on the vibrating arm 21 side of the connection electrode 23-2b has a curvature R1, and the side on the base 29 side of the connection electrode 23-2b has a curvature R2. Since the curvature is constant, electric discharge hardly occurs. The side on the vibrating arm 21 side of the connection electrode 25-2b is formed with a curvature R3, and the side of the base 29 side of the connection electrode 25-2b and the side of the base electrode 25-3a are formed with a curvature R4. The base 29 side of the other connection electrode 23-2b and the side of the base electrode 23-3a are formed with a curvature R5. Since all the sides have a constant curvature, it is easy to design and discharge is not easily generated.

  Although not shown, the electrode pattern 23 or the electrode pattern 25 may be formed by a curve composed of sides drawn by a quadratic function or a cubic function. For example, it may be a cycloid curve, a cardioid curve or an asteroid curve.

FIG. 4 is a diagram showing the electrostatic withstand voltage test result (HBM), in which the vertical axis represents the failure frequency (%) and the horizontal axis represents the withstand voltage (V). This is a test result of the tuning-fork type piezoelectric vibrating piece 120 having an electrode pattern in which the chain line is only a straight line as shown in FIG. On the other hand, the solid line is a test result of the tuning-fork type piezoelectric vibrating piece 20 in which the connection electrode is formed by only a curve as shown in FIG.
As can be seen from the test results of FIG. 4, the tuning fork type piezoelectric vibrating piece 20 of the present invention does not have a defect up to about 1700V. Further, at an electrostatic voltage of 1700 V or higher, the failure frequency of the tuning fork type piezoelectric vibrating piece 20 of the present invention is lower than the failure frequency of the tuning fork type piezoelectric vibrating piece 120.

<Piezoelectric vibration device manufacturing process>
FIG. 5 is a flowchart showing all steps of manufacturing the package tuning fork resonator 50 of the present embodiment.
<< Step of forming outer shape of piezoelectric vibrating piece and forming groove of vibrating arm >>
In step S112, a corrosion resistant film is formed on the entire surface of the quartz single crystal wafer 10 by a technique such as sputtering or vapor deposition. That is, when using the crystal single crystal wafer 10 as a piezoelectric material, it is difficult to directly form a film of gold (Au), silver (Ag), or the like, so that chromium (Cr), titanium (Ti), etc. Is used. That is, in this embodiment, a metal film in which a gold layer is stacked on a chromium layer is used as the corrosion resistant film. For example, the thickness of the chromium layer is about 500 angstroms, and the thickness of the gold layer is about 500 angstroms.

  In step S114, a photoresist layer is uniformly applied to the entire surface of the quartz single crystal wafer 10 on which the chromium layer and the gold layer are formed by a technique such as spin coating. As the photoresist layer, for example, a positive photoresist made of novolak resin can be used.

  Next, in step S116, the quartz single crystal wafer 10 on which the photoresist layer is applied to the external pattern of the tuning fork type quartz vibrating piece 20 drawn on a photomask (not shown) is exposed using an exposure apparatus. In step S116, the pattern of the tuning-fork type crystal vibrating piece 20 drawn on the photomask is exposed on both sides of the crystal single crystal wafer 10 using i-line exposure light of 365 nm using a double-side exposure apparatus.

  In step S118, the photoresist layer of the crystal single crystal wafer 10 is developed, and the exposed photoresist layer is removed. Further, the gold layer exposed from the photoresist layer is etched using, for example, an aqueous solution of iodine and potassium iodide. Next, the chromium layer exposed by removing the gold layer is etched with, for example, an aqueous solution of ceric ammonium nitrate and acetic acid. The concentration of the aqueous solution, the temperature, and the time of immersion in the aqueous solution are adjusted so that excess portions are not eroded. Thus, the corrosion resistant film can be removed.

In step S120, a photoresist layer for forming the groove 31 is uniformly applied to the entire surface by a technique such as spin coating or spray coating.
In step S122, a photomask corresponding to the groove 31 is prepared, and the quartz single crystal wafer 10 coated with the photoresist layer is exposed in the groove 31. Since the groove portions 31 need to be formed on both surfaces of the tuning fork type crystal vibrating piece 20, both surfaces of the tuning fork type crystal vibrating piece 20 are exposed using exposure light. The double-sided exposure apparatus can be used to expose both sides of the tuning-fork type crystal vibrating piece 20 at once, and the single-sided exposure apparatus can be used to expose one side of the tuning-fork type crystal vibrating piece 20 so that the tuning-fork type crystal vibrating piece 20 can be exposed. It can also be turned over to expose the other side.
In step S124, after the photoresist layer is developed, the exposed photoresist is removed. The remaining photoresist becomes a photoresist corresponding to the groove 31. The gold layer exposed from the photoresist layer is not etched here, but is etched in step S128.

In step S126, wet etching is performed on the quartz material exposed from the photoresist layer and the corrosion-resistant film so that the outer shape of the tuning-fork type quartz vibrating piece 20 is obtained using a hydrofluoric acid solution as an etchant. This wet etching takes about 6 hours to about 15 hours, although the time varies depending on the concentration, type and temperature of the hydrofluoric acid solution.
Next, in step S128, the groove 31 is etched. That is, the exposed gold layer corresponding to the groove 31 is etched with, for example, an aqueous solution of iodine and potassium iodide.

Subsequently, in step S <b> 130, wet etching is performed using the hydrofluoric acid solution as an etchant so that the quartz material exposed from the corrosion-resistant film has the outer shape of the groove 31. Half-etching is performed in which the etching is terminated halfway so that the groove 31 does not become a through hole. Through these steps, the groove 31 is formed in the tuning fork type crystal vibrating piece 20 at an accurate position.
In step S132, the photoresist layer and the corrosion resistant film that are no longer needed are removed.

<< Electrode Formation Process >>
In step S134, the tuning fork type crystal vibrating piece 20 is washed with pure water, and a metal film for forming an excitation electrode or the like as a drive electrode is formed on the entire surface of the tuning fork type crystal vibrating piece 20 by a technique such as vapor deposition or sputtering. .
In step S136, a photoresist is applied to the entire surface using a spray. Since the grooves 31 or the corners are formed, the photoresist is uniformly applied to the grooves 31 and the like.

  In step S138, a photomask (not shown) corresponding to the electrode pattern 23 and the electrode pattern 25 is prepared, and the crystal single crystal wafer 10 coated with the photoresist layer is exposed to the electrode pattern. It is necessary to form the electrode pattern 23 and the electrode pattern 25 on both surfaces of the tuning fork type crystal vibrating piece 20. In the photomask corresponding to the electrode pattern, the sides of the electrode pattern are formed in a curved shape like the electrode pattern shown in FIG.

In step S140, after the photoresist layer is developed, the exposed photoresist is removed. The remaining photoresist becomes a photoresist corresponding to the electrode pattern. Next, the metal film to be an electrode is etched. That is, the gold layer exposed from the photoresist layer corresponding to the electrode pattern is etched with, for example, an aqueous solution of iodine and potassium iodide, and then the chromium layer is etched with an aqueous solution of, for example, ceric ammonium nitrate and acetic acid.
Subsequently, the photoresist is removed in step S142. Through these steps, an excitation electrode or the like is formed on the tuning fork type crystal vibrating piece 20 with an accurate position and electrode width.

<Packaging>
<< Configuration of tuning fork crystal unit >>
FIG. 6A is a sectional view showing a ceramic package tuning fork type crystal resonator 50 according to the present embodiment. This package tuning fork type resonator 50 made of ceramic uses the tuning fork type crystal vibrating piece 20 of the plurality of embodiments described above. The tuning fork type crystal vibrating piece 20 is mounted on a package 51 by a conductive adhesive 31. Thereafter, the lid 56 and the sealing material 58 are fixed by seam welding or the like, so that the tuning fork type crystal vibrating piece 20 is sealed in the package 51.

<< Configuration of tuning fork crystal oscillator >>
FIG. 9B shows the tuning fork crystal oscillator 60. The tuning fork crystal oscillator 60 has the same configuration in many parts as the above-described ceramic package tuning fork resonator 50. Therefore, the configurations, operations, and the like of the ceramic package tuning fork vibrator 50 and the tuning fork crystal vibrating piece 20 are denoted by the same reference numerals, and the description thereof is omitted.

  The tuning fork type crystal oscillator 60 shown in FIG. 9B includes an integrated circuit 61 on the base portion 51a below the tuning fork type crystal vibrating piece 20 of the ceramic package tuning fork vibrator 50 shown in FIG. 9A. It is arranged. That is, in the tuning fork crystal oscillator 60, when the tuning fork type crystal vibrating piece 20 disposed therein vibrates, the vibration is input to the integrated circuit 61, and then functions as an oscillator by extracting a predetermined frequency signal. Will do. Such an integrated circuit 61 is mounted on the package 51, and then the tuning fork type crystal vibrating piece 20 is mounted on the package 51 with the conductive adhesive 31.

<< Configuration of Cylinder Type Tuning Fork Crystal Oscillator >>
FIG. 9C is a schematic view showing a cylinder type tuning fork vibrator 70. The cylinder type tuning fork vibrator 70 uses the tuning fork type crystal vibrating piece 20 described above. The cylinder type tuning fork vibrator 70 has a metal cap 75 for accommodating the tuning fork type crystal vibrating piece 20 therein. The cap 75 is press-fitted into the stem 73 so that the inside thereof is maintained in a vacuum state. Two leads 71 for holding the tuning fork type crystal vibrating piece 20 accommodated in the cap 75 are arranged. The lead 71 and the tuning-fork type crystal vibrating piece 20 are conductively joined with a conductive adhesive 31. The tuning fork type crystal vibrating piece 20 vibrates when a constant current is applied from the electrode portion.

  In each embodiment, the tuning-fork type crystal vibrating piece 20 forms the vibrating arm 21 and the vibrating arm 22. However, the present invention is not limited to this, and the number of vibrating arms may be three or four or more. Further, although the embodiments using a quartz single crystal wafer have been described, piezoelectric materials such as lithium tantalate and lithium niobate can be used in addition to quartz. The present invention can also be applied to a gyro that detects angular acceleration.

(A) is a top view of the tuning fork type | mold crystal vibrating piece 20 of this invention, (b) is the side view. FIG. 2 is a cross-sectional view taken along C2-C2 illustrated in FIG. (A) is the second electrode patterns 23-2 and 25-2, and (b) is the third electrode patterns 23-3 and 25-3. It is the figure which showed the result of the electrostatic withstand voltage test. It is a flowchart of the process of a piezoelectric vibrating piece and an electrode pattern. It is a figure which shows the aspect of the packaged piezoelectric device. It is the front view and side view which show the conventional tuning fork type crystal vibrating piece 120.

Explanation of symbols

20 ... tuning-fork type crystal vibrating pieces 21, 22 ... vibrating arms 23, 25 ... electrode, 23a, 25a ... base electrode, 23b, 25b ... connection electrode, 23c, 25c ... side electrode, 23d, 25d ... surface electrode 28 ... connection part 29 ... Base 50 ... Package tuning fork type vibrator 51 ... Package 60 ... Tuning fork type crystal vibrator 70 ... Cylinder type tuning fork vibrator 120 ... Conventional tuning fork type crystal vibrating piece

Claims (6)

A base on which first and second base electrodes are formed;
A first vibrating arm portion and a second vibrating arm portion protruding from the base portion;
First and second excitation electrodes formed on the first and second vibrating arms;
A first connection electrode portion for connecting the first base electrode and the first excitation electrode with a curved electrode;
A second connection electrode part for connecting the second base electrode and the second excitation electrode with a curved electrode;
A piezoelectric vibrating piece comprising: At the point where the straight side of the first base electrode or the straight side of the first excitation electrode matches the curved side of the first connection electrode unit, the curved side of the first connection electrode unit The piezoelectric vibrating piece according to claim 1, wherein a tangential direction coincides with a direction of a side of the straight line. 3. The piezoelectric vibrating piece according to claim 1, wherein a side where the first base electrode and the second base electrode face each other is formed in a curved shape. 3. The piezoelectric vibrating piece according to claim 1, wherein one side of the first connection electrode portion is formed with a constant curvature, and the other side is formed with a different constant curvature. 4. The piezoelectric vibrating piece according to claim 1, wherein one side of the first connection electrode portion and one side of the first base electrode are formed with the same curvature. 5. A piezoelectric vibrating piece according to any one of claims 1 to 5,
A package containing the piezoelectric vibrating piece;
A piezoelectric device comprising: a sealing portion that seals the package.