JP4548148B2 - Piezoelectric vibrating piece and piezoelectric device - Google Patents

Description

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

Piezoelectric vibrators and piezoelectrics in small information devices such as HDDs (hard disk drives), mobile computers, IC cards, mobile communication devices such as mobile phones, car phones, and paging systems, and piezoelectric gyro sensors Piezoelectric devices such as oscillators are widely used.
FIG. 5 is a schematic plan view showing an example of a piezoelectric vibrating piece conventionally used in a piezoelectric device, and FIG. 6 is an end view taken along the line BB of FIG.

In the figure, a piezoelectric vibrating reed 1 is formed by etching a piezoelectric material such as quartz to form the outer shape shown in the figure. A rectangular base 2 attached to a package (not shown) or the like, A pair of vibrating arms 3 and 4 extended rightward is provided, and long grooves 3a and 4a are formed on the main surfaces (front and back surfaces) of these vibrating arms, and necessary driving electrodes are formed. (See Patent Document 1).
In such a piezoelectric vibrating piece 1, when a driving voltage is applied via a driving electrode, the piezoelectric vibrating piece 1 is flexibly oscillated so that the distal ends of the vibrating arms 3 and 4 approach and separate from each other. The signal of the frequency of is extracted.

  By the way, such a piezoelectric vibrating piece 1 is required to be formed in a small size in accordance with the downsizing of the above-described various products to which the piezoelectric device using the piezoelectric vibrating piece 1 is attached. It must be formed as small as possible. In particular, it is required to reduce the total length AL1. Since downsizing of products is constantly progressing, the piezoelectric vibrating reed 1 is required to have a structure that can be made smaller.

Here, the frequency f of the piezoelectric vibrating reed 1 that is a tuning fork type piezoelectric vibrating reed as shown in the figure is proportional to w / l × 2 where l is the length of the vibrating arms 3 and 4 and w is the arm width. .
This means that when the size of the total length AL1 in FIG. 5 is reduced in order to reduce the size of the piezoelectric vibrating piece 1 that is long in one direction, the frequency increases when the length l of the vibrating arm is shortened. To do. In addition, the frequency decreases as the width w of the vibrating arm decreases. From this, in order to maintain the conventional frequency and reduce the size, it is necessary to reduce the arm width w while shortening the length of the vibrating arm to some extent.

JP 2002-261575 A

  By the way, in reducing the size of the piezoelectric vibrating reed 1, the length l of the vibrating arms 3 and 4 is shortened and the arm width w is decreased in order to maintain the conventional frequency, for example, 32 kHz (32.768 kHz). However, when processing the small piezoelectric vibrating piece 1, particularly when trying to reduce the arm width w while maintaining the characteristics, there are the following difficulties.

Specifically, it is necessary to process the long grooves 3a and 4a as shown in FIG. For example, when a crystal wafer is used as a material, the dimension t in FIG. 6 is not changed because the material is constrained by processing conditions. For example, when the conventional one is 100 μm, the size is reduced. Is also 100 μm.
On the other hand, the arm width w is assumed to be about 50 μm due to the downsizing of what was previously 100 μm. When the arm width is 100 μm, the groove width C1 is about 70 μm and the side wall thicknesses S1 and S1 are about 15 μm. If the arm width w is about 50 μm, the groove width C1 is about 40 μm and the side wall thicknesses S1 and S1. Must be about 5 μm each.

When such a piezoelectric vibrating piece is made, the rigidity of the vibrating arms 3 and 4 is greatly reduced, and the amplitude in the Z direction in FIG. The bending vibrations along the X direction of the arms 3 and 4 become bending vibrations as exaggerated by arrows SF and SF.
FIG. 7 is a graph showing drive characteristics when the piezoelectric vibrating piece is miniaturized with the conventional structure. When the drive power level is gradually increased along the horizontal axis of the figure, the frequency change on the vertical axis changes. It occurs in the negative direction. This indicates that the component of the Z-direction vibration in FIG. 6 increases, resulting in vibration with a lot of energy loss, which causes an increase in CI (crystal impedance) value.

  As an effective measure for suppressing the CI value, there is a method in which the long grooves 3a and 4a described with reference to FIG. 5 are lengthened to increase the area for forming the driving electrodes. However, the piezoelectric vibrating piece has a plurality of vibration modes, and the fundamental wave that is usually used is, for example, 32.768 kHz, whereas the second harmonic of the piezoelectric vibrating piece 1 is around 250 kHz. . Even if the long grooves 3a and 4a are lengthened and the CI value of the fundamental wave can be lowered, the CI value of the second harmonic is also lowered, so that the CI value which is the CI value of the harmonic / the CI value of the fundamental wave. As the ratio decreases, drive characteristics deteriorate.

  That is, FIG. 8 shows a state in which the CI value ratio is deteriorated. When the CI value ratio is smaller than 1 and becomes negative, the piezoelectric vibrating reed 1 is excited by the fundamental wave. When the drive level is changed by changing the drive voltage, the second harmonic acts on the normal vibration state of the fundamental wave, and an abnormal oscillation called parametric excitation occurs, resulting in excitation. The state becomes unstable.

  The present invention has been made to solve the above-described problems. A piezoelectric vibrating piece that can be reduced in size without suppressing the CI value and without deteriorating the vibration characteristics, and a piezoelectric element using such a piezoelectric vibrating piece. The purpose is to provide a device.

According to the first aspect of the present invention, in the first invention, a base portion formed of a piezoelectric material, a plurality of vibrating arms formed integrally with the base portion and extending from one end side of the base portion, and a longitudinal direction of each vibrating arm And a driving electrode formed in the long groove, and each of the vibrating arms gradually moves from the base side of the vibrating arm toward the distal end side of the vibrating arm. a first reduced width portion s width dimension is provided with the longitudinal groove in the component parts and the reduced width, between the base of the base side of the vibrating arm, to a point where the first reduced width portion begins, a second reduced width portion of reduced width larger width than the first reduced width portion toward the distal end side, and further toward the distal end side from the distal end of the first reduced width portion The arm width extends further to the tip side than the end of the long groove on the tip side. A straight portion having a configuration, the distal end of the straight portion as a change point P, and a widened portion in which the width from the change point P increases gradually toward the distal end side, the piezoelectric vibrating piece having a Achieved.

According to the configuration of the first invention, the vibrating arm is formed with a long groove, and the driving electrode is provided in the groove, so that the electric field efficiency of the piezoelectric material constituting the vibrating arm is enhanced. On the other hand, the rigidity of the region where the long groove is formed is lowered accordingly.
For this reason, by forming the reduced width portion in the vibrating arm, the rigidity in the vicinity of the base of the vibrating arm is increased compared to the tip side, so that the flexural vibration is stabilized, the CI value is reduced, and the secondary value is reduced. It is considered that the “node” of the vibration at the time of the vibration in the higher harmonics can be located on the tip side. As a result, even if the CI value of the second harmonic is suppressed even if the CI value of the fundamental wave is suppressed by elongating the long groove to increase the electric field efficiency of the piezoelectric material and stabilizing the flexural vibration. It is possible to prevent a decrease.
Further, by providing the straight portion, the rigidity of the length range in which the straight portion is formed does not decrease, and the arm width ahead from the change point P is increased. This means that, in the flexural vibration of the vibrating arm, the portion acting as a weight can be positioned on the tip side, and the vibration “node” at the time of vibration in the second harmonic is positioned more on the tip side. Therefore, it is possible to more reliably reduce the CI value of the second harmonic while suppressing the CI value of the fundamental wave, so that oscillation due to the second harmonic is less likely to occur.
Thus, even if the size is reduced, only the CI value of the fundamental wave can be suppressed, and a piezoelectric vibrating piece that does not deteriorate the drive characteristics can be provided.

Further in the structure of the first invention, the reduced width portion first reduced width portion, further from the root to said base of said oscillating arm, between up to which the first reduced width portion begins, the tip And a second reduced width portion having a width that is larger than that of the first reduced width portion toward the side .
According to the configuration of the first invention, the rigidity of the vicinity of the base of the vibrating arm is further reinforced by the second reduced width portion. Thereby, the bending vibration of the vibrating arm can be further stabilized, and the CI value of the fundamental wave can be suppressed.

According to a second aspect of the present invention, in the configuration of the first aspect of the present invention, the base is extended in the width direction from the other end side that is a predetermined distance away from the one end side, and is the same as the vibrating arm outside the vibrating arm. A support arm extending in the direction is provided.
According to the configuration of the third aspect of the invention, the vibrating arm that bends and vibrates extends from one end of the base, and the support arm extends from the other end of the base having a predetermined length. For this reason, when the support arm is bonded to the base of the package or the like by bonding or the like, the stress change generated at the bonded portion due to a change in ambient temperature or a drop impact is caused by the change in the support arm. There is almost no influence on the vibrating arm at a distance from the joint location to the other end of the base, and further at a distance of a predetermined length of the base, and therefore the temperature characteristics are particularly good.
In addition, vibration leakage from a vibrating arm that bends and vibrates on the contrary is hardly reached because the base portion is separated by a predetermined length before reaching the supporting arm that is separated from the base portion. That is, if the base length is extremely short, the leaked component of the bending vibration spreads over the entire support arm, making it difficult to control. However, in the present invention, there is no such fear.
And since such an action can be obtained, the supporting arm is extended in the width direction from the other end of the base portion, and is configured to extend in the same direction as the vibrating arm outside the vibrating arm. The size of can be made compact.

According to a third aspect of the present invention, there is provided a piezoelectric device in which a piezoelectric vibrating piece is housed in a package or case, wherein the piezoelectric vibrating piece is formed of a base portion made of a piezoelectric material, and the base portion. are formed integrally provided with a plurality of vibrating arms extending from one end of the base, said a long groove formed along a longitudinal direction of the vibration arms, and an electrode for driving formed in the long groove, said each vibrating arms, said toward the tip end side of the vibrating arm from the base side to said base portion of the vibrating arm, a first reduced width portion having the longitudinal groove on the component gradually width has reduced width, the A second contraction having a width that is larger than the first contracted width part toward the distal end side from the base on the base side of the vibrating arm to a portion where the first contracted width part starts. and width portion, further front from the tip end of the first reduced width portion It extends toward the serial distal side, and wherein a straight portion having a distal end configured to extend unchanged further Udehaba the free end portion than the end of the elongated groove, changes the tip end of the straight portion P is achieved by a piezoelectric device having , as P, a widened portion in which the width dimension gradually increases from the change point P toward the distal end side.

1 and 2 show a first embodiment of a piezoelectric device of the present invention, FIG. 1 is a schematic plan view thereof, FIG. 2 is an end view taken along line AA of FIG. 1, and FIG. 4 is a partially enlarged plan view of a portion including vibrating arms 35 and 36 of the piezoelectric vibrating piece 32 of FIG.
In these drawings, the piezoelectric device 30 shows an example in which a piezoelectric vibrator is configured. The piezoelectric device 30 houses a piezoelectric vibrating piece 32 in a package 57 as a base.
As shown in FIGS. 1 and 2, the package 57 is formed in a rectangular box shape, for example. Specifically, the package 57 is formed by laminating a first substrate 55 and a second substrate 56. For example, an aluminum oxide ceramic green sheet is formed as an insulating material to form a shape shown in the figure. After that, it is formed by sintering.

As shown in FIG. 2, the package 57 forms a space of the internal space S by removing the material inside the second substrate 56. This internal space S is a housing space for housing the piezoelectric vibrating piece 32. Then, on the electrode portions 31, 31 formed on the first substrate 55, the later-described extraction electrode forming portions of the support arms 61, 62 of the piezoelectric vibrating piece 32 are mounted using the conductive adhesives 43, 43. Put together.
For this reason, after fixing and supporting the piezoelectric vibrating piece 32 by the conductive adhesive 43, due to a difference in linear expansion coefficient between the material constituting the piezoelectric vibrating piece 32 and the material constituting the package 57, etc. Residual stress exists in the base 51.

  The electrode portions 31 are connected to the mounting terminals 41 on the back surface of the package through conductive through holes. The package 57 is hermetically sealed by housing the piezoelectric vibrating piece 32 and then bonding the transparent glass lid 40 using the sealing material 58. Thus, after the lid 40 is sealed, the frequency can be adjusted by trimming the electrodes of the piezoelectric vibrating piece 32 by irradiating laser light from the outside.

The piezoelectric vibrating piece 32 is formed of, for example, quartz, and a piezoelectric material such as lithium tantalate or lithium niobate can be used in addition to quartz. As shown in FIG. 1, the piezoelectric vibrating piece 32 includes a base 51 and a pair of vibrating arms 35 and 36 that extend in parallel from the one end (right end in the drawing) to the right. It has.
Long grooves 33 and 34 extending in the length direction are preferably formed on the front and back surfaces of the main surfaces of the vibrating arms 35 and 36, respectively. As shown in FIGS. 1 and 2, driving electrodes are formed in the long grooves. Excitation electrodes 37 and 38 are provided.

The pair of vibrating arms 35 and 36 of the piezoelectric vibrating piece 32 have the same structure, and the characteristics of the vibrating arm 36 will be described with reference to FIGS. 1 and 3.
The resonating arm 36 has a first reduced width portion 71 that starts from the vicinity of the base with respect to the base portion 51 and extends to the distal end side thereof by a certain length L1. The first reduced width portion 71 is a portion where the arm width W1 is gradually reduced toward the tip. The first reduced width portion 71 continues substantially to the vicinity of the tip of the long groove 34, and the straight portion 72, which is a portion where the arm width W1 does not change over a predetermined distance from the end of the first reduced width portion 71, is L2. The length is formed.
Further, the end of the straight portion 72 is a width change point P, and the distal end side is further the length L3 from this P portion, and a widened portion 73 in which the arm width W1 is gradually widened is formed.
In other words, in this embodiment, the widened portion 73 that is the tip of each vibrating arm 35, 36 is gradually widened in a slightly tapered shape so that the weight is increased and it plays the role of a weight. Thereby, the bending vibration of the vibrating arm is easily performed.

Preferably, the base of the vibrating arm 36 with respect to the base 51 includes a first portion that is abruptly reduced toward the distal end within a distance range of L4 until the first reduced width portion 71 starts. Two reduced width portions 74 are provided.
Accordingly, the rigidity of the vicinity of the base of the vibrating arm 36 is further enhanced by the second reduced width portion 74. For this reason, the flexural vibration of the vibrating arm can be further stabilized, and the CI value of the fundamental wave can be suppressed.

Further, the piezoelectric vibrating piece 32 extends in the width direction of the base 51 at the other end (left end in the drawing) separated by a predetermined distance BL (base length) in FIG. 1 from one end where the vibrating arm of the base 51 is formed. The supporting arms 61 and 36 extending in parallel with the vibrating arms 35 and 36 in the extending direction of the vibrating arms 35 and 36 (rightward in FIG. 1) at positions on both outer sides of the vibrating arms 35 and 36. 62.
The tuning fork-shaped outer shape of the piezoelectric vibrating piece 32 and the long groove provided in each vibrating arm should be precisely formed by wet etching a material such as a quartz wafer with a hydrofluoric acid solution or dry etching, for example. Can do.

Excitation electrodes 37 and 38, which are driving electrodes, are formed in the long grooves 33 and 34 and on the side surfaces of the vibrating arms, so that the electrodes in the long grooves and the electrodes provided on the side surfaces of each vibrating arm are paired. Has been. The excitation electrodes 37 and 38 are routed around the supporting arms 61 and 62 as extraction electrodes 37a and 38a, respectively. As a result, when the piezoelectric device 30 is mounted on a mounting substrate or the like, an external driving voltage is drawn from the mounting terminal 41 through the electrode portions 31 and 31 to the support arms 61 and 62 of the piezoelectric vibrating piece 32. It is transmitted to the electrodes 37a and 38a and is transmitted to the excitation electrodes 37 and 38.
Then, by applying a driving voltage to the excitation electrodes in the long grooves 33 and 34, the electric field efficiency inside the region where the long grooves of the respective vibrating arms are formed can be increased during driving.

Preferably, the base 51 is provided with a recess or notch formed by partially reducing the widthwise dimension of the base 51 on both side edges at a position sufficiently away from the end of the base 51 on the vibrating arm side. Can be provided. For example, the depth of the cut portion is preferably reduced to the extent that it matches the outer side edges of the adjacent vibrating arms 35 and 36, respectively.
Thereby, when the vibrating arms 35 and 36 are bent and vibrated, it is possible to suppress vibration leakage from leaking to the base 51 side and propagating to the supporting arms 61 and 62, and to reduce the CI value.

Here, in this embodiment, the place where the supporting arms 61 and 62 described above extend, that is, the other end 53 of the base 51 has a distance BL sufficiently far from the base 52 of the vibrating arms 35 and 36. Has been.
This distance BL is preferably a dimension that exceeds the arm width dimension W1 in the vicinity of the roots of the vibrating arms 35 and 36.
That is, when the vibrating arms 35 and 36 of the tuning fork-type vibrating piece flexurally vibrate, the range in which the vibration leakage is transmitted toward the base 51 correlates with the arm width dimension W1 of the vibrating arms 35 and 36. The inventor pays attention to this point, and has the knowledge that the base end of the supporting arms 61 and 62 must be provided at an appropriate position.

  Therefore, in the present embodiment, a position exceeding the dimension corresponding to the arm width dimension W1 of the vibrating arm, starting from the root portion 52 of the vibrating arm, at the location 53 serving as the base end of the supporting arms 61 and 62 is determined. By selecting, it can be set as the structure which suppresses more reliably that the vibration leakage from the vibrating arms 35 and 36 propagates to the supporting arms 61 and 62 side. Therefore, in order to suppress the CI value and obtain the effect of the support arm described later, the position of the other end portion 53 is set to the base portion of the vibrating arms 35 and 36 (that is, one end portion of the base portion 51). It is preferable that the distance of the above BL is separated from the position of 52.

Thus, in this embodiment, since the supporting arms 61 and 62 are joined to the package 57 side by the conductive adhesive 43, the stress generated at the joining portion due to a change in ambient temperature, a drop impact, or the like. The vibration arm 35, the change is separated by a bent distance from the joint portion of the support arms 61, 62 to the other end 53 of the base 51 and a distance corresponding to the length of the base 51 exceeding the distance BL. 36 is hardly affected, and therefore the temperature characteristics are particularly good.
In addition, the vibration leakage from the vibrating arms 35 and 36 that bend and vibrate on the contrary is separated by a predetermined length of the base 51 that exceeds the distance BL before reaching the supporting arms 61 and 62 that are separated from the base 51. Because of that, it hardly reaches.

Here, if the length of the base portion 51 is extremely short, it is conceivable that the component in which the bending vibration leaks spreads over the entire support arms 61 and 62, and it becomes difficult to control. Severe situations are avoided sufficiently.
Further, in addition to being able to obtain such an action, the support arms 61 and 62 are extended in the width direction from the other end 53 of the base 51 as shown in the figure, and outside the vibrating arms 35 and 36, Since the configuration extends in the same direction as the vibrating arm, the overall size can be made compact.
Further, in this embodiment, as shown in FIG. 1, the tips of the support arms 61 and 62 are formed so as to be closer to the base 51 than the tips of the vibrating arms 35 and 36. Also in this point, the size of the piezoelectric vibrating piece 32 can be made compact.

Here, FIG. 3 shows an example of dimensions of each part of the resonating arm. Since each dimension is the same in the resonating arms 35 and 36, only the resonating arm 36 will be described.
The groove width MW of the long groove 34 of the vibrating arm 36 is, for example, about 30 to 40 μm. A distance BW between the vibrating arm 35 and the vibrating arm 36 is about 80 μm. Regarding the wall thickness of the wall portion of the piezoelectric material sandwiching the long groove 34 of the vibrating arm 36 from both sides, the wall thickness DW1 in the vicinity of the base 51 is, for example, about 10 μm, and the wall thickness DW2 in the vicinity of the tip of the long groove 34 is, for example, about 5 μm. Has been.

FIG. 4 shows a second embodiment of the piezoelectric vibrating piece.
In the piezoelectric vibrating piece 32-1 in FIG. 4, the same reference numerals as those in the first embodiment in FIGS. 1 and 2 have the same configuration. explain.
The piezoelectric vibrating piece 32-1 is formed of a base 51 made of a piezoelectric material, a plurality of vibrating arms 35, 36 that are formed integrally with the base 51 and extend in parallel with each other from one end side of the base, and each vibrating arm 35. , 36, and the width dimensions of the vibrating arms 35, 36 are gradually increased from the vicinity of the base to the base 51 of the vibrating arm toward the tip side. A first reduced width portion 71 that is reduced in width, a straight portion 72 that extends from the end of the first reduced width portion 71 toward the distal end side without changing in arm width, and the end of the straight portion 72, the width The width change point P is connected to the widened portion 73 whose dimensions gradually increase toward the front end side, and the drive electrode is not shown.
Accordingly, the piezoelectric vibrating piece 32 is the same as that of the first embodiment except that the supporting arms 61 and 62 are not provided.
Here, for example, the length L1 of the first reduced width portion 71, the length L2 of the straight portion 72, and the length L3 of the widened portion 73 are L1: L2: L3 and 0.738: 0.262: 0. .200 (all units are “mm”), and it can be seen that this is a very small piezoelectric vibrating piece.

Therefore, all the functions and effects of the first embodiment other than the functions and effects of the support arm can be exhibited. Since the vibrating arms 35 and 36 have the same configuration, only the vibrating arm 36 will be described. The vibrating arm 36 is provided with a long groove 34 and a driving electrode is provided in the groove. The electric field efficiency of the piezoelectric material constituting is increased. On the other hand, the rigidity of the region where the long groove 36 is formed is reduced accordingly.
For this reason, by forming the first reduced width portion 71 in the vibrating arm 36, the rigidity in the vicinity of the base of the vibrating arm 36 is increased compared to the tip side, so that the flexural vibration is stabilized and the CI value is increased. In addition, it is considered that vibration “nodes” at the time of vibration at the second harmonic can be positioned more on the tip side. Thus, even if the CI value of the second harmonic is suppressed even if the CI value of the fundamental wave is suppressed by elongating the long groove 36 to increase the electric field efficiency of the piezoelectric material and stabilizing the bending vibration. Can be prevented from incurring a decrease.

The present invention is not limited to the above-described embodiment. The configurations of the embodiment and the modified examples can be combined or omitted as appropriate, and can be combined with other configurations not shown.
The present invention is not limited to the case where the piezoelectric vibrating piece is accommodated in a box-shaped package, the case where the piezoelectric vibrating piece is accommodated in a cylindrical container, the piezoelectric vibrating piece functioning as a gyro sensor, Can be applied to any piezoelectric device using a piezoelectric vibrating piece regardless of the name of a piezoelectric vibrator, a piezoelectric oscillator, or the like. Further, the piezoelectric vibrating piece 32 forms a pair of vibrating arms, but is not limited to this, and the number of vibrating arms may be three or four or more.

The schematic plan view which shows embodiment of the piezoelectric device of this invention. The AA cut | disconnection end elevation of FIG. FIG. 2 is a partially enlarged plan view of the vicinity of a vibrating arm of the piezoelectric vibrating piece in FIG. 1. The schematic plan view which shows 2nd Embodiment of the piezoelectric vibrating piece used for the piezoelectric device of this invention. FIG. 6 is a schematic plan view of a conventional piezoelectric vibrating piece. FIG. 6 is an end view taken along line B-B in FIG. 5. The graph which shows the temperature-frequency characteristic of the piezoelectric vibrating piece used for the piezoelectric device of FIG. The graph which shows the temperature-CI value characteristic of the piezoelectric vibrating piece used for the piezoelectric device of FIG.

Explanation of symbols

  30 ... piezoelectric device, 32 ... piezoelectric vibrating piece, 33,34 ... long groove, 35,36 ... vibrating arm, 61,62 ... supporting arm

Claims (3)

A base formed of piezoelectric material;
A plurality of vibrating arms formed integrally with the base and extending from one end side of the base;
A long groove formed along the longitudinal direction of each vibrating arm;
An electrode for driving formed in the long groove,
And each vibrating arm, the first reduced width portion having a width dimension gradually toward the base side to the tip side of the vibrating arm with respect to said base of said oscillating arm is provided with the longitudinal groove in the component parts and the reduced width,
A second width that is larger than the first reduced width portion toward the distal end side from the base side of the vibrating arm to the base portion to a location where the first reduced width portion starts. A reduced width portion;
Straight having the structure extends further toward the tip side, and extending no change in Udehaba further to the distal side than the distal end of the elongated groove from the tip end of the first reduced width portion And
A piezoelectric vibrating piece comprising: an end on the tip side of the straight portion as a change point P ; and a widened portion whose width dimension gradually increases from the change point P toward the tip side. A support arm that extends in the width direction from the other end side of the base portion away from the one end side by the predetermined distance and extends in the same direction as the vibrating arm outside the vibrating arm. Item 2. The piezoelectric vibrating piece according to Item 1 . A piezoelectric device containing a piezoelectric vibrating piece in a package or case,
The piezoelectric vibrating piece is
A base formed of piezoelectric material;
A plurality of vibrating arms formed integrally with the base and extending from one end side of the base;
A long groove formed along the longitudinal direction of each vibrating arm;
An electrode for driving formed in the long groove,
Each of the vibrating arms includes a first reduced width portion including the long groove in a component portion whose width dimension is gradually reduced from the base side of the vibrating arm toward the distal end side of the vibrating arm ;
A second width that is larger than the first reduced width portion toward the distal end side from the base side of the vibrating arm to the base portion to a location where the first reduced width portion starts. A reduced width portion;
Straight having the structure extends further toward the tip side, and extending no change in Udehaba further to the distal side than the distal end of the elongated groove from the tip end of the first reduced width portion And
With the end of the straight portion on the tip side as a change point P, a widened portion where the width dimension gradually increases from the change point P toward the tip side ,
A piezoelectric device comprising:

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