JP2019037009A - Piezoelectric vibrating piece and piezoelectric vibrator - Google Patents

Abstract

To provide a piezoelectric vibrating piece and a piezoelectric vibrator, reducing the occurrence of vibration leakage while suppressing a support arm from being damaged, and additionally high in mounting strength.SOLUTION: A piezoelectric vibrating piece 400 includes: a base 410; a pair of vibration arms 420A, 420B extending from the base 410 in a first (+Y) direction and placed so as to be separated from each other in a second (X) direction crossing the first (+Y) direction; and support arm 430 extending from the base 410 in the first (+Y) direction. The support arm 430 includes: a first arm 433 which extends, from between places where the vibration arms 420A, 420B extend in the base 410, in a length direction of the vibration arms 420A, 420B, and in which a width of a length along the second (X) direction is formed so as to gradually narrow toward a distal end 430Z side of the support arm 430; and a second arm 434 which extends from the first arm 433 in the first (+Y) direction and in which a width thereof is formed so as to widen toward the distal end 430Z side.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a piezoelectric vibrating piece and a piezoelectric vibrator.

  Conventionally, a cellular phone or a portable information terminal often employs a piezoelectric vibrator using a crystal or the like as a device used for a time source, a timing source such as a control signal, a reference signal source, or the like. As this type of piezoelectric vibrator, a piezoelectric vibrator in which a piezoelectric vibrating piece is hermetically sealed in a package in which a cavity is formed is known.

  As such a piezoelectric vibrating piece, one having a base and a pair of vibrating arms and support arms extending from the base is known. In addition, the base end part of the support arm is formed in a tapered shape so that the width gradually becomes narrower toward the front end side, and a widened piezoelectric vibrating piece is proposed in the front end part of the support arm. (See Patent Document 1 below).

  The support arm has a second straight line portion extending in parallel with the extending direction of the vibrating arm from the base portion, a curved portion that is continuously formed at the distal end of the second linear portion, and is curved, and the distal end of the curved portion Has been proposed (see Patent Document 2 below). The piezoelectric vibrating piece includes a first linear portion that is provided continuously with the first straight portion extending in parallel with the extending direction of the vibrating arm.

JP 2010-87574 A JP 2009-118302 A

  However, in the piezoelectric vibrating piece described in Patent Document 1, a stepped portion is formed at the boundary portion between the wide portion on the distal end side of the support arm and the tapered portion on the proximal end side. Therefore, so-called etching residue is likely to occur in the stepped portion. For this reason, in the said step part, a chip | tip arises in a support arm or there exists a problem that a support arm breaks.

Further, in the piezoelectric vibrating piece described in Patent Document 2, since the support arm is curved, it may not be possible to reduce the occurrence of vibration leakage (leakage of vibration energy) from the piezoelectric vibrating piece to the package side. .
In addition, since the width dimension of the support arm (the length in the separation direction of the pair of support arms) is constant, a sufficient bonding area cannot be secured on the tip side of the first straight portion mounted on the package, and the mounting is not possible. There is also a problem that the strength becomes insufficient.

  Accordingly, the present invention has been made in view of the above circumstances, and provides a piezoelectric vibrating piece and a piezoelectric vibrator having high mounting strength while reducing occurrence of vibration leakage while suppressing breakage of a support arm portion. .

In order to achieve the above object, the present invention employs the following means.
That is, a piezoelectric vibrating piece according to the present invention includes a base, a pair of vibrating arms that extend in the first direction from the base, and are spaced apart in a second direction intersecting the first direction, and the base. A support arm portion extending in the first direction, and the support arm portion extends in a length direction of the vibrating arm portion from a portion of the base portion where the vibrating arm portion extends. A first arm portion formed such that a width that is a length along the second direction gradually decreases toward the tip end side of the support arm portion, and the first arm portion extends from the first arm portion to the first direction. And a second arm portion formed so that the width becomes wider toward the tip end side.

In the piezoelectric vibrating piece configured as described above, the first arm portion of the support arm portion is formed so that the width gradually becomes narrower toward the distal end portion side, so that occurrence of vibration leakage can be suppressed. .
In addition, since the second arm portion of the support arm portion is formed so that the width gradually increases toward the tip end side, the area on the tip end side of the second arm portion can be increased. Therefore, when the distal end side of the second arm portion is mounted on the package, the mounting area can be increased, and thus the mounting strength of the piezoelectric vibrating piece with respect to the package can be increased.
In addition, the width of the support arm portion where the etching residue is likely to occur, that is, the base end side of the first arm portion, is wider than the distal end side of the first arm portion. Therefore, since the strength on the proximal end side of the first arm portion can be ensured, damage on the proximal end side of the support arm portion can be suppressed. Further, when a stepped portion or a notch is formed in the support arm portion, an etching residue is likely to occur, but the support arm portion is formed so that its width gradually changes in the first direction. Therefore, the generation of etching residue in the support arm portion is suppressed along the first direction.

Further, in the piezoelectric vibrating piece according to the present invention, the support arm portion has a tip arm portion formed continuously with the second arm portion and extending along the length direction,
It is desirable that a mount portion on which the mount electrode is formed is provided on the main surface of the tip arm portion.

  In the piezoelectric vibrating piece according to the present invention, it is preferable that the mount portion on which the mount electrode is formed is provided on the main surface of the first arm portion and the main surface of the second arm portion.

In the piezoelectric vibrating piece according to the present invention, the support arm portion includes an extended arm portion extending from the base portion, a first arm portion formed continuously with the extended arm portion, and the first arm portion. And a second arm portion formed continuously,
It is desirable that a mount portion having a mount electrode is provided from the main surface of the extending arm portion to the first arm portion, and further provided on the main surface of the second arm portion.

In the piezoelectric vibrating piece according to the present invention, it is preferable that both side surfaces of the first arm portion and the second arm portion are formed in a flat shape.

  In the piezoelectric vibrating piece configured as described above, since both side surfaces of the first arm portion and the second arm portion are formed in a planar shape, the support arm portion can be easily manufactured.

  Further, in the piezoelectric vibrating piece according to the present invention, the support arm portion includes an extension arm portion that extends from the base portion side, and a distal end side is connected to the base end side of the first arm portion, and the extension arm A deformed portion may be formed on the base side of the side surface of the portion.

  In the piezoelectric vibrating piece configured as described above, the first arm portion formed so that the width becomes narrower in the first direction is provided closer to the distal end portion of the support arm portion than the extending arm portion. . Therefore, since the base end side of the support arm portion where the deformed portion is likely to occur, that is, the extended arm portion, is formed so that the width is wider than the front end side of the first arm portion, the base end of the support arm portion Damage due to stress concentration on the side can be suppressed.

  In the piezoelectric vibrating piece according to the present invention, the support arm portion may have a tip arm portion that extends in the first direction from the second arm portion and has a constant width.

In the piezoelectric vibrating piece configured as described above, since the width of the tip arm portion is constant compared to the case where the width is narrowed along the first direction, the area of the tip arm portion is widened. In the present invention, the conductive adhesive applied to the tip arm portion for mounting tends to wet and spread along the width direction (second direction) of the support arm portion, so that it may be too wet in the first direction. It is suppressed. Therefore, it is suppressed that the conductive adhesive reaches the first arm portion that does not need to be applied because it is too wet and the tip arm portion and the second arm portion can be reliably mounted on the package.
Moreover, since the width | variety of a front-end | tip arm part is made constant, a conductive adhesive is uniformly apply | coated along a 1st direction in a front-end | tip arm part. Therefore, since the variation in mass along the first direction in the distal arm is suppressed, the mounting strength can be increased.

  In the piezoelectric vibrating piece according to the present invention, a boundary portion between the first arm portion and the second arm portion is located closer to the base side than an intermediate position in the first direction in the support arm portion. Also good.

  In the piezoelectric vibrating piece configured as described above, since the boundary portion is disposed on the base side with respect to the intermediate position in the first direction of the support arm portion, the distance from the distal end portion of the support arm portion to the boundary portion is increased. be able to. Therefore, even if the conductive adhesive applied to the tip end portion of the support arm portion wets and spreads in the first direction, the reaching to the boundary portion is suppressed. Therefore, it is suppressed that a conductive adhesive adheres to a boundary part and a vibration leaks through a conductive adhesive.

  Further, in the piezoelectric vibrating piece according to the present invention, one side surface of the first arm portion and the second arm portion is formed in a planar shape extending in the first direction, and the other side of the first arm portion is formed. The side surface is formed in a planar shape so as to gradually approach the one side surface of the first arm portion as it goes toward the tip portion side, and the other side surface of the second arm portion is gradually set toward the tip portion side. It may be formed in a flat shape so as to be separated from the one side surface of the second arm portion.

  In the piezoelectric vibrating piece configured as described above, one side surface of the first arm portion and the second arm portion is formed in a planar shape extending in the first direction, and thus the support arm portion is easily manufactured. be able to.

  In the piezoelectric vibrating piece according to the present invention, the rate of change along the first direction of the width dimension of the second arm portion is a change along the first direction of the width dimension of the first arm portion. It may be larger than the rate.

  In the piezoelectric vibrating piece configured in this way, the rate of change along the first direction of the width dimension of the second arm portion is larger than the rate of change along the first direction of the width dimension of the first arm portion. Therefore, since the rate of change at which the width of the second arm portion is wide is large, vibration leakage can be reliably suppressed.

  In addition, a piezoelectric vibrator according to the present invention includes a base member, and a lid member that is overlapped and joined to the base member and has a hermetically sealed cavity formed between the base member and the base member. And the piezoelectric vibrating piece according to any one of the above, which is mounted on a mounting surface of the base member and accommodated inside the cavity.

In the piezoelectric vibrator configured as described above, the first arm portion of the support arm portion is formed so that the width gradually becomes narrower toward the distal end portion side, so that occurrence of vibration leakage can be suppressed. .
In addition, since the second arm portion of the support arm portion is formed so that the width gradually increases toward the tip end side, the area of the second arm portion on the tip end side is the width along the first direction. Becomes wider than when it becomes narrower. Therefore, when the distal end side of the second arm portion is mounted on the package, the mounting area can be increased, and thus the mounting strength of the piezoelectric vibrating piece with respect to the package can be increased.
In addition, the width of the support arm portion where the etching residue is likely to occur, that is, the base end side of the first arm portion, is wider than the distal end side of the first arm portion. Therefore, since the strength on the proximal end side of the first arm portion can be ensured, damage on the proximal end side of the support arm portion can be suppressed. Further, when a stepped portion or a notch is formed in the support arm portion, an etching residue is likely to occur, but the support arm portion is formed so that its width gradually changes in the first direction. Therefore, the generation of etching residue in the support arm portion is suppressed along the first direction.

  According to the piezoelectric vibrating piece and the piezoelectric vibrator of the present invention, it is possible to reduce the occurrence of vibration leakage and further increase the mounting strength while suppressing the breakage of the support arm portion.

1 is an external perspective view showing a piezoelectric vibrator according to a first embodiment of the present invention. 1 is an exploded perspective view showing a piezoelectric vibrator according to a first embodiment of the present invention. It is a top view which shows the internal structure of the piezoelectric vibrator which concerns on 1st embodiment of this invention. It is AA sectional drawing in FIG. 1 is an external perspective view showing a piezoelectric vibrating piece constituting a piezoelectric vibrator according to a first embodiment of the present invention. It is (a) top view and (b) side view which show the piezoelectric vibrating piece which comprises the piezoelectric vibrator which concerns on 1st embodiment of this invention. It is (a) top view and (b) side view which show the piezoelectric vibrating piece which comprises the piezoelectric vibrator which concerns on the modification 1 of 1st embodiment of this invention. It is (a) top view which shows the piezoelectric vibrating piece which comprises the piezoelectric vibrator which concerns on the modification 2 of 1st embodiment of this invention, (b) It is a side view. (A) It is a top view of the piezoelectric vibrating piece which concerns on 2nd embodiment of this invention, (b) It is a top view of the piezoelectric vibrating piece which concerns on the modification 1 of 2nd embodiment, (c) 2nd embodiment FIG. 10 is a plan view of a piezoelectric vibrating piece according to Modification Example 2 of FIG.

(First embodiment)
A piezoelectric vibrator will be described as a first embodiment of the present invention.
FIG. 1 is an external perspective view showing a piezoelectric vibrator according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view showing the piezoelectric vibrator according to the first embodiment of the present invention. FIG. 3 is a plan view showing the internal structure of the piezoelectric vibrator according to the first embodiment of the present invention. FIG. 4 is a cross-sectional view taken along the line AA in FIG.
1 to 9 described below, an XYZ coordinate system is set, and the positional relationship of each member will be described with reference to the XYZ coordinate system. At this time, the thickness direction of the piezoelectric vibrator 1 (see FIG. 1) is the Z-axis direction, the longitudinal direction of the piezoelectric vibrator 1 is the Y-axis direction, and the short direction of the piezoelectric vibrator 1 is the Y-axis direction and the Z-axis direction. The direction orthogonal to both of these is the X-axis direction.

(Piezoelectric vibrator)
As shown in FIGS. 1 to 4, the piezoelectric vibrator 1 is a so-called ceramic package type surface-mount vibrator having a substantially rectangular parallelepiped shape. The piezoelectric vibrator 1 includes a package 2 in which a hermetically sealed cavity C1 is formed, and a piezoelectric vibrating piece 100 accommodated in the cavity C1.

  The package 2 includes a package body (base member) 3 and a sealing plate (lid member) 4 that is overlapped and joined to the package body 3.

  The package main body 3 includes a first base substrate 50 and a second base substrate 51 that are joined in a state of being overlapped with each other, and a seal ring 52 that is joined to the upper portion of the second base substrate 51.

  The first base substrate 50 is a ceramic substrate formed in a substantially rectangular shape in plan view. The second base substrate 51 is a ceramic substrate formed in a substantially rectangular shape in plan view having the same outer shape as the first base substrate 50, and is sintered in a state of being stacked on the first base substrate 50. Etc. are integrally joined together.

  At the four corners of the first base substrate 50 and the second base substrate 51, cut-out portions 58 having a ¼ arc shape in plan view are formed over the entire thickness direction of the first base substrate 50 and the second base substrate 51. Yes. The first base substrate 50 and the second base substrate 51 are formed, for example, by stacking and joining two wafer-like ceramic substrates, and then forming a plurality of through-holes penetrating both ceramic substrates in a matrix. It is produced by cutting both ceramic substrates into a lattice shape with the through hole as a reference. At that time, the through-hole is divided into four, so that the above-described notch 58 is obtained.

  The upper surface of the second base substrate 51 is a mounting surface 51A on which the piezoelectric vibrating piece 100 is mounted.

  The second base substrate 51 has a through hole 51H in the thickness direction (Z-axis direction). The through hole 51H is formed in a square shape with rounded four corners in plan view.

  In a state where the second base substrate 51 and the first base substrate 50 are overlapped and joined to each other, the through hole 51H extends from the mounting surface 51A of the second base substrate 51 in the thickness direction (Z It is a recess 51P that is recessed in the axial direction.

  The first base substrate 50 and the second base substrate 51 are made of ceramics. Specific ceramic materials include, for example, alumina HTCC (High Temperature Co-Fired Ceramic), glass ceramics LTCC (LTCC ( Low Temperature Co-Fired Ceramic) and the like.

The seal ring 52 is a conductive frame member that is slightly smaller than the outer shape of the first base substrate 50 and the second base substrate 51. The seal ring 52 is bonded to the mounting surface 51 </ b> A of the second base substrate 51.
Specifically, the seal ring 52 is bonded onto the mounting surface 51A or formed on the mounting surface 51A by baking with a brazing material such as silver solder or a solder material (for example, in addition to electrolytic plating or electroless plating, Bonding is performed by welding or the like to a metal bonding layer formed by vapor deposition or sputtering.

The material of the seal ring 52 includes, for example, a nickel-based alloy. Specifically, the seal ring 52 may be selected from Kovar, Elinvar, Invar, 42-alloy, and the like. In particular, as the material of the seal ring 52, it is preferable to select a material having a thermal expansion coefficient close to that of the first base substrate 50 and the second base substrate 51 which are made of ceramic. For example, when alumina having a thermal expansion coefficient of 6.8 × 10 ⁻⁶ / ° C. is used as the first base substrate 50 and the second base substrate 51, the thermal expansion coefficient is 5.2 × 10 − as the seal ring 52. It is preferable to use 6 / ° C. Kovar or 42-alloy having a thermal expansion coefficient of 4.5 × 10 ⁻⁶ / ° C. or more and 6.5 × 10 ⁻⁶ / ° C. or less.

  The sealing plate 4 is a conductive substrate that is stacked on top of the seal ring 52. The sealing plate 4 is airtightly joined to the seal ring 52 by baking with a brazing material such as silver brazing or a solder material. A space defined by the sealing plate 4, the seal ring 52, and the mounting surface 51A of the second base substrate 51 functions as a hermetically sealed cavity C1.

  In addition, as a welding method of the sealing board 4, seam welding by making a roller electrode contact, laser welding, ultrasonic welding, etc. are mentioned, for example. Further, in order to make the welding between the sealing plate 4 and the seal ring 52 more reliable, a bonding layer such as nickel or gold that is familiar to each other is provided at least on the lower surface of the sealing plate 4 and the upper surface of the seal ring 52. It is preferable to form.

  On the mounting surface 51 </ b> A of the second base substrate 51, convex portions 60 and 60 are provided. The convex portion 60 is formed so as to protrude to the side where the piezoelectric vibrating piece 100 is mounted, and the shape in plan view is not particularly limited, and may be a rectangular shape or another shape (in the drawing). Rectangular).

  The upper surface of the convex portion 60 is parallel to the mounting surface 51A. Two convex portions 60 are provided at symmetrical positions on the mounting surface 51A on the −Y axis direction side of the concave portion 51P with the center in the width direction (X axis direction) of the mounting surface 51A interposed therebetween. Electrode pads 61 </ b> A and 61 </ b> B that are connection electrodes to the piezoelectric vibrating piece 100 are formed on the upper surfaces of the convex portions 60 and 60, respectively.

  On the lower surface of the first base substrate 50, a pair of external electrodes 62 </ b> A and 62 </ b> B are formed at intervals in the longitudinal direction (Y-axis direction) of the piezoelectric vibrator 1.

  The electrode pads 61A and 61B and the external electrodes 62A and 62B are, for example, a single layer film made of a single metal formed by vapor deposition or sputtering, or a stacked film in which different metals are stacked.

  The electrode pad 61A and the external electrode 62A are electrically connected by a first wiring (not shown). The electrode pad 61B and the external electrode 62B are electrically connected by a second wiring (not shown).

The first wiring includes, for example, a first through electrode that passes through the first base substrate 50 in the thickness direction (Z-axis direction) and is electrically connected to the external electrode 62A, and a second base substrate 51 in the thickness direction (Z-axis direction). ) Through the electrode pad 61 </ b> A and a connection wiring that is provided between the first base substrate 50 and the second base substrate 51 and connects the first through electrode and the second through electrode. ,including. The second wiring that connects the electrode pad 61B and the external electrode 62B has the same configuration as the first wiring. The configurations of the first wiring and the second wiring can be selected as appropriate.
Are electrically connected to each other.

(Piezoelectric vibrating piece)
FIG. 5 is an external perspective view showing the piezoelectric vibrating piece 100. 6A is a plan view of the piezoelectric vibrating piece 100, and FIG. 6B is a side view thereof.
As shown in FIGS. 5 and 6, the piezoelectric vibrating piece 100 is formed in a flat plate shape. The piezoelectric vibrating piece 100 includes a base 110, a pair of vibrating arm portions 120A and 120B that are connected to the base portion 110 and arranged side by side in the width direction (X-axis direction), and the width of the vibrating arm portions 120A and 120B in the base portion 110. And a pair of support arm portions 130A and 130B connected to both sides in the direction (X-axis direction).

The piezoelectric vibrating piece 100 is a side arm type vibrating piece formed of a piezoelectric material such as quartz, lithium tantalate, or lithium niobate, and vibrates when a predetermined voltage is applied.
The thickness in the direction perpendicular to the surface of the piezoelectric vibrating piece 100 (length in the Z-axis direction) can be set to 30 μm, for example.

  In the present embodiment, the base 110, the pair of vibrating arm portions 120A and 120B, and the support arm portions 130A and 130B are integrally formed, and adjacent portions are continuous without an interface. In FIG. 6, in order to show the range of each part, the base end or front-end | tip of each part is shown with the dashed-two dotted line.

  The base 110 connects the vibrating arm portions 120A and 120B and the support arm portions 130A and 130B. In a plan view (XY plane view), the base 110 is formed in a rectangular shape. Support arm portions 130A and 130B are connected to end portions on both sides (± X side) in the width direction of the vibrating arm portions 120A and 120B in the base portion 110, respectively. The vibrating arm portions 120A and 120B are connected to one side (+ Y side) in the length direction of the support arm portions 130A and 130B in the base portion 110.

  The vibrating arm portions 120A and 120B extend from the base portion 110 in the length direction (+ Y-axis direction, first direction) of the support arm portions 130A and 130B. The vibrating arm portions 120A and 120B are provided side by side in a direction (second direction, X-axis direction) perpendicular to the longitudinal direction (Y-axis direction) and parallel to the surface of the piezoelectric vibrating piece 100.

  The vibrating arm portions 120A and 120B are provided at the end of the strip portion 121 and the strip portion 121 linearly extending with a uniform width (length in the X-axis direction), and the width (length in the X-axis direction) is strip-shaped. And a hammer portion 122 wider than the portion 121.

The belt-like portion 121 is formed with a groove 121M extending in a belt-like shape in the length direction (+ Y-axis direction) of the support arm portions 130A and 130B.
In the present embodiment, one groove 121M is formed in each vibrating arm 120A, 120B, but a plurality of grooves are formed apart from each other in the length direction (+ Y-axis direction) of the support arms 130A, 130B. May be. For example, a long groove portion in the + Y axis direction is formed on the distal end side of the vibrating arm portions 120A and 120B, and a short groove portion in the + Y axis direction is formed on the proximal end side of the vibrating arm portions 120A and 120B. Also good.

  The hammer portion 122 is formed so as to extend in the length direction (+ Y-axis direction) of the vibrating arm portions 120 </ b> A and 120 </ b> B from the distal end portion of the band-shaped portion 121. The width of the hammer portion 122 (length in the X-axis direction) is formed larger than the width (length in the X-axis direction) of the vibrating arm portions 120A and 120B. The hammer portion 122 is set to a free end that vibrates in the width direction (X-axis direction) with the base portion 110 as a fixed end.

  In addition, excitation electrodes (not shown) that vibrate the pair of vibrating arm portions 120A and 120B are formed on the outer surfaces of the pair of vibrating arm portions 120A and 120B.

  The support arm portions 130A and 130B extend from the base portion 110 in the length direction (+ Y axis direction) of the vibrating arm portions 120A and 120B. The support arm portions 130A and 130B are provided side by side in a direction (X-axis direction) perpendicular to the longitudinal direction (Y-axis direction) and parallel to the surface of the piezoelectric vibrating piece 100.

  The support arm portions 130A and 130B respectively include a base end arm portion 131 extending from the base portion 110 in the width direction (X-axis direction) of the vibrating arm portions 120A and 120B, and lengths of the vibrating arm portions 120A and 120B from the base end arm portion 131. Extending arm 132 extending in the direction (+ Y-axis direction). Further, the support arm portions 130A and 130B include a first arm portion 133 that extends from the extending arm portion 132 in the length direction (+ Y-axis direction) of the vibrating arm portions 120A and 120B, and a vibrating arm portion 120A that extends from the first arm portion 133. , 120B extending in the length direction (+ Y-axis direction). Further, the support arm portions 130A and 130B include a tip arm portion 135 extending from the second arm portion 134 in the length direction (+ Y-axis direction) of the vibrating arm portions 120A and 120B, and an inclined arm portion provided on the tip arm portion 135. 136. The proximal arm portion 131, the extended arm portion 132, the first arm portion 133, the second arm portion 134, the distal arm portion 135, and the inclined arm portion 136 are integrally formed.

  The base end arm portion 131 extends from the −Y axis side of the base portion 1110 in the width direction (X axis direction) of the vibrating arm portions 120A and 120B. The length of the base end arm portion 131 in the Y-axis direction is shorter than the length of the base portion 110 in the Y-axis direction.

  The extending arm part 132 has a constant width (length in the X-axis direction) over the length direction (+ Y-axis direction). The side surface on the base 110 side of the extending arm portion 132, in this embodiment, the side surface 132S facing the vibrating arm portions 120A and 120B side in the extending arm portion 132 and the length direction (+ Y-axis direction) in the base end arm portion 131 are directed. Etching residue E (deformed portion) is formed at the corner formed by the surface 131S. The etching residue E is not formed on the first arm portion 133.

  The first arm 133 has the same width (X-axis direction length) on the base 110 side (−Y axis side) as the width on the distal end side of the extended arm 132, and the distal ends of the support arm portions 130 </ b> A and 130 </ b> B. The width is gradually narrowed toward the part 130Z side, that is, in the + Y-axis direction.

  In the present embodiment, both side surfaces 133S and 133T orthogonal to the main surface (XY surface) 133A of the first arm portion 133 are formed in a planar shape. Both side surfaces 133S and 133T of the first arm portion 133 are formed so as to gradually approach each other in the length direction (+ Y-axis direction) of the support arm portions 130A and 130B.

  The second arm part 134 has the same width (X-axis direction length) on the base 110 side (−Y axis side) as the width on the tip side of the first arm part 133. The second arm portion 134 is formed such that the width gradually increases toward the tip end portion 130Z side of the support arm portions 130A and 130B, that is, in the + Y-axis direction.

  Both side surfaces 134S and 134T orthogonal to the main surface (XY surface) 134A of the second arm portion 134 are formed continuously with the both side surfaces 133S and 133T of the first arm portion 133, respectively. In the present embodiment, both side surfaces 134S and 134T of the second arm portion 134 are formed in a planar shape. Both side surfaces 134S and 134T of the second arm portion 134 are formed so as to gradually become separated from each other in the length direction (+ Y-axis direction) of the support arm portions 130A and 130B.

  In the present embodiment, the first arm portion 133 and the second arm portion 134 are formed symmetrically across the boundary portion 133X between the first arm portion 133 and the second arm portion 134. Thereby, the change rate of the width dimension along the length direction (+ Y-axis direction) of the first arm part 133 is the change rate of the width dimension along the length direction (+ Y-axis direction) of the second arm part 134. , Are identical.

  Further, in the length direction (+ Y-axis direction) of the support arm portions 130A and 130B, the boundary portion 133X between the first arm portion 133 and the second arm portion 134 is an intermediate position in the first direction of the support arm portions 130A and 130B. It is located closer to the base 110 than 130M.

  The distal arm portion 135 is formed continuously with the second arm portion 134 and extends along the length direction (+ Y-axis direction). The width (the length in the X-axis direction) of the distal arm portion 135 is the same as the width on the distal end side of the second arm portion 134 and is constant over the length direction (+ Y-axis direction).

  Mount portions 141A and 141B are provided on the opposing surface (XY surface) 135B surface of the distal arm portion 135. The positions where the mount parts 141A and 141B are provided are positions that become nodes of vibration when the support arm parts 130A and 130B vibrate.

  The inclined arm part 136 is provided at the tip of the tip arm part 135. Of the side surfaces 136S and 136T of the inclined arm portion 136, on the side surface 136T farther from the vibrating arm portions 120A and 120B, the vibrating arm portion 120A gradually increases in the length direction (+ Y-axis direction) of the support arm portions 130A and 130B. , 120B, an inclined surface 136X is provided so as to be close to 120B.

  Then, as shown in FIG. 4, the piezoelectric vibrating piece 100 is arranged such that mount electrodes (not shown) formed on the mount portions 141A and 141B are in contact with the electrode pads 61A and 61B via the conductive adhesive 70. Mounted.

  Accordingly, the piezoelectric vibrating piece 100 is supported in a state where the main surface is parallel to the mounting surface 51A of the second base substrate 51 and is electrically connected to the pair of electrode pads 61A and 61B, respectively. It is said that.

  When operating the piezoelectric vibrator 1 configured as described above, a predetermined drive voltage is applied to the external electrodes 62A and 62B. As a result, a current can be passed through the excitation electrode of the piezoelectric vibrating piece 100, and one vibrating arm 120A and the other vibrating arm 120B can be vibrated at a predetermined frequency along the surface of the piezoelectric vibrating piece 100. it can. By using this vibration, the piezoelectric vibrator 1 can be used as a time source, a control signal timing source, a reference signal source, and the like.

  In addition, it is also possible to use a metal bump instead of the conductive adhesive as the conductive bonding material for bonding the mount electrode to the electrode pads 61A and 61B. The common point between conductive adhesive and metal bump is that it is a paste with fluidity at the early stage of bonding, and it is a conductive bonding material that has the property of solidifying and developing bonding strength at the later stage of bonding. is there.

  In the piezoelectric vibrator 1 configured in this way, the first arm 133 of the support arm portions 130A and 130B is formed so that the width gradually becomes narrower toward the distal end portion 130Z side, so that vibration leakage occurs. Can be suppressed.

  In addition, since the second arm portion 134 of the support arm portions 130A and 130B is formed so that the width gradually increases toward the tip portion 130Z side, the area on the tip side of the second arm portion 134 is increased. Can do. Therefore, when the distal end side of the second arm part 134, that is, when the distal arm part 135 is mounted on the package 2, the mounting area (the area of the mount parts 141A and 141B) can be increased. The mounting strength for the package 2 can be increased.

  Further, the width of the support arm portions 130A and 130B where the etching residue E is likely to occur, that is, the extended arm portion 132, is wider than the distal end side of the first arm portion 133. Therefore, since the rigidity on the base end side of the support arm portions 130A and 130B can be ensured, damage due to stress concentration on the base end side of the support arm portions 130A and 130B can be suppressed.

  Further, if stepped portions or notches are formed in the support arm portions 130A and 130B, an etching residue E is likely to occur, but the width of the support arm portions 130A and 130B gradually changes along the longitudinal direction (Y-axis direction). It is formed to do. Therefore, in the support arm portions 130A and 130B, the generation of the etching residue E is suppressed along the longitudinal direction (Y-axis direction).

  Further, since both side surfaces 133S, 133T, 134S, and 134T of the first arm portion 133 and the second arm portion 134 are formed in a flat shape, the support arm portions 130A and 130B can be easily manufactured.

  In the present embodiment, for example, since the width of the distal arm portion 135 is constant over the longitudinal direction (Y-axis direction) than when the width is narrower along the longitudinal direction (Y-axis direction), the distal arm The area of the part 135 is increased. As a result, the conductive adhesive 70 applied to the mount portions 141A and 141B for mounting is likely to wet and spread along the width direction (X-axis direction) of the support arm portions 130A and 130B. Excessive wetting and spreading in the longitudinal direction (Y-axis direction) is suppressed. Therefore, the conductive adhesive 70 is prevented from reaching the first arm portion 133 that does not need to be applied because it is too wet and spread, so that the tip arm portion 135 can be reliably mounted on the package 2.

  Further, since the width of the distal arm portion 135 is constant, the conductive adhesive 70 is uniformly applied along the longitudinal direction (Y-axis direction) of the piezoelectric vibrator 1 at the distal arm portion 135. Therefore, since the variation in mass along the longitudinal direction (Y-axis direction) of the piezoelectric vibrator 1 in the tip arm portion 135 is suppressed, the mounting strength can be increased.

  Further, since the boundary portion 133X is disposed on the base 110 side with respect to the intermediate position 130M in the longitudinal direction (Y-axis direction) of the piezoelectric vibrator 1 of the support arm portions 130A and 130B, the distal end portions of the support arm portions 130A and 130B The distance from 130Z to the boundary portion 133X can be increased. Therefore, even if the conductive adhesive 70 applied to the mount portions 141A and 141B wets and spreads in the longitudinal direction (Y-axis direction) of the piezoelectric vibrator 1, it does not reach the boundary portion 133X. Therefore, it is suppressed that the conductive adhesive 70 adheres to the boundary portion 133 </ b> X and the vibration leaks through the conductive adhesive 70.

(Modification 1 of the first embodiment)
Next, Modification 1 of the first embodiment described above will be described mainly with reference to FIG.
In addition, in the modified example and embodiment described below, about the structure which is common in embodiment shown above, the same code | symbol is attached | subjected in a figure and the description is abbreviate | omitted.

FIGS. 7A and 7B are a plan view and a side view showing a piezoelectric vibrating piece constituting the piezoelectric vibrator according to the first modification of the first embodiment of the present invention.
As shown in FIG. 7, the inner side surface 233S closer to the vibrating arm portions 120A and 120B among the both side surfaces 233S and 233T of the first arm portion 233 constituting the piezoelectric vibrating piece 200 is the length of the support arm portions 230A and 230B. Along the vertical direction (+ Y-axis direction), it is disposed on the YZ plane orthogonal to the main surface (XY plane).

  Further, the outer surface 233T far from the vibrating arm portions 120A and 120B among the both side surfaces 233S and 233T of the first arm portion 233 is the length direction (+ Y of the support arm portions 230A and 230B, as in the first embodiment. It is formed so as to gradually approach the inner surface 233S facing each other as it goes in the axial direction. In this way, the first arm portion 233 is formed so that the width gradually decreases toward the tip end portion 230Z side of the support arm portions 230A and 230B, that is, in the + Y-axis direction.

  Further, the inner side surface 234S closer to the vibrating arm portions 120A and 120B among the both side surfaces 234S and 234T of the second arm portion 234 constituting the piezoelectric vibrating piece 200 is flush with the inner side surface 233S of the first arm portion 233. Is arranged. That is, they are arranged on the YZ plane that is along the length direction (+ Y-axis direction) of the support arm portions 230A and 230B and orthogonal to the main surface (XY plane).

  Further, the outer side surface 234T far from the vibrating arm portions 120A and 120B among the both side surfaces 234S and 234T of the second arm portion 234 is continuous with the outer side surface 233T of the first arm portion 233 as in the first embodiment. Is formed. The outer side surface 234T of the second arm portion 234 is formed so as to be gradually separated from the inner side surface 234S facing each other in the length direction (+ Y-axis direction) of the support arm portions 230A and 230B. In this way, the second arm portion 234 is formed so that the width gradually increases toward the tip end portion 230Z side of the support arm portions 230A and 230B, that is, in the + Y-axis direction.

In the piezoelectric vibrating piece 200 configured in this manner, the inner side surface 233S of the first arm portion 233 and the inner side surface 234S of the second arm portion 234 are directed in the length direction (+ Y-axis direction) of the support arm portions 230A and 230B. Therefore, the support arm portions 230A and 230B can be easily manufactured.
The outer surface of the first arm part and the outer surface of the second arm part are formed in a planar shape extending in the length direction (+ Y axis direction) of the support arm part, and the inner side surface of the first arm part is The inner side surface of the second arm portion is formed in the length direction (+ Y axis direction) of the support arm portion so as to gradually approach the opposite outer surface as it goes in the length direction (+ Y axis direction) of the support arm portion. You may be comprised so that it may space apart from the outer surface which opposes gradually as it goes.

(Modification 2 of the first embodiment)
Next, Modification 2 of the first embodiment described above will be described mainly with reference to FIG.
FIG. 8A is a plan view and FIG. 8B is a side view showing a piezoelectric vibrating piece constituting a piezoelectric vibrator according to Modification 2 of the first embodiment of the present invention.
As shown in FIG. 8, in the piezoelectric vibrating piece 300, both side surfaces 333S and 333T of the first arm portion 333 gradually approach each other as they go in the length direction (+ Y-axis direction) of the support arm portions 330A and 330B. Is formed. Both side surfaces 334S and 334T of the second arm portion 334 are formed so as to be gradually separated from each other in the length direction (+ Y-axis direction) of the support arm portions 330A and 330B.

  The change rate of the width dimension along the length direction (+ Y axis direction) of the second arm portion 334 is larger than the change rate of the width dimension along the length direction (+ Y axis direction) of the first arm portion 333. . In other words, the width dimension of the first arm portion 333 is gradually narrowed in the length direction (+ Y axis direction), whereas the width dimension of the second arm portion 334 is in the length direction (+ Y axis direction). It is formed so as to widen suddenly.

  In the piezoelectric vibrating piece 300 configured as described above, since the rate of change of the width dimension in which the width of the second arm portion 334 is large is large, vibration leakage can be reliably suppressed.

(Second embodiment)
Next, the piezoelectric vibrating piece according to the second embodiment will be described mainly with reference to FIG.
FIG. 9A is a plan view of the piezoelectric vibrating piece according to the second embodiment of the present invention.
As shown in FIG. 9A, the piezoelectric vibrating piece 400 is a center arm type vibrating piece. The piezoelectric vibrating piece 400 includes a base portion 410, a pair of vibrating arm portions 420A and 420B, and a support arm portion 430.

  The vibrating arm portions 420A and 420B extend from the base portion 410 in the same direction (+ Y-axis direction). The vibrating arm portions 420A and 420B are provided side by side in a direction (X-axis direction) perpendicular to the longitudinal direction (Y-axis direction) and parallel to the surface of the piezoelectric vibrating piece 400. Excitation electrodes (not shown) that vibrate the pair of vibrating arm portions 420A and 420B are formed on the outer surfaces of the vibrating arm portions 420A and 420B.

  Hammer portions 422 are provided at the tip portions of the vibrating arm portions 420A and 420B, respectively. The hammer portion 422 is formed so as to extend in the length direction (+ Y-axis direction) of the vibrating arm portions 420A and 420B from the tip portions of the vibrating arm portions 420A and 420B, respectively. The width of the hammer portion 422 (length in the X-axis direction) is formed larger than the width of the vibrating arm portions 420A and 420B (length in the X-axis direction). The hammer portion 422 is set as a free end that vibrates in the width direction (X-axis direction) with the base portion 410 as a fixed end.

  The support arm portion 430 extends in the length direction (+ Y-axis direction) of the vibrating arm portions 420A and 420B from between the portions of the base portion 410 where the vibrating arm portions 420A and 420B extend. The support arm portion 430 includes a first arm portion 433 extending from the base portion 410, a second arm portion 434 formed continuously with the first arm portion 433, and a tip arm formed continuously with the second arm portion 434. Part 435.

  The first arm portion 433 is formed so that the width gradually decreases toward the tip end portion 430Z side of the support arm portion 430, that is, in the + Y-axis direction.

  Both side surfaces 433S and 433T of the first arm portion 433 are formed in a planar shape. Both side surfaces 433S and 433T of the first arm portion 433 are formed so as to gradually approach each other in the length direction (+ Y-axis direction) of the support arm portion 430.

  The second arm 434 has the same width (X-axis direction length) on the base 410 side (−Y axis side) as the width on the tip side of the first arm portion 433, and the tip portion 430 </ b> Z of the support arm portion 430. The width is gradually increased toward the side, that is, in the + Y-axis direction.

  Both side surfaces 434S and 434T of the second arm portion 434 are formed continuously with both side surfaces 433S and 433T of the first arm portion 433, respectively. Both side surfaces 434S and 434T of the second arm portion 434 are formed in a planar shape. Both side surfaces 434S and 434T of the second arm portion 434 are formed so as to gradually become separated from each other as they go in the length direction (+ Y-axis direction) of the support arm portion 430.

  In the present embodiment, the first arm part 433 and the second arm part 434 are formed symmetrically with a boundary part 433X between the first arm part 433 and the second arm part 434 interposed therebetween. Thereby, the change rate of the width dimension along the length direction (+ Y-axis direction) of the first arm part 433 is the change rate of the width dimension along the length direction (+ Y-axis direction) of the second arm part 434. , Are identical.

  The tip arm portion 435 is formed continuously with the second arm portion 434 and extends along the length direction (+ Y-axis direction). The width of the distal arm portion 435 is the same as the width on the distal end side of the second arm portion 434, and the width (length in the X-axis direction) is constant.

  Mount portions 441A and 441B are provided on the main surface (XY surface) of the distal arm portion 435 so as to be separated from each other in the length direction (+ Y-axis direction) of the support arm portion 430. The positions where the mount parts 141A and 141B are provided are positions that become nodes of vibration when the support arm part 430 vibrates.

  The piezoelectric vibrating reed 400 is mounted via a conductive adhesive (not shown) so that mount electrodes (not shown) formed on the mount portions 441A and 441B are in contact with electrode pads (not shown). Has been.

  As a result, the piezoelectric vibrating reed 400 is supported in a state in which the main surface is parallel to the mounting surface 51A (see FIG. 2) of the second base substrate 51 (see FIG. 2), and each of the pair of electrode pads. It is in an electrically connected state.

  When operating the piezoelectric vibrator 1 configured as described above, a predetermined drive voltage is applied to the external electrodes 62A and 62B. As a result, a current can flow through the excitation electrode of the piezoelectric vibrating piece 400, and one vibrating arm portion 420A and the other vibrating arm portion 420B can be vibrated at a predetermined frequency along the surface of the piezoelectric vibrating piece 400. it can.

(Modification 1 of the second embodiment)
Next, Modification 1 of the second embodiment described above will be described mainly with reference to FIG.
FIG. 9B is a plan view of the piezoelectric vibrating piece according to the first modification of the second embodiment.
As shown in FIG. 9B, the support arm portion 530 constituting the piezoelectric vibrating piece 500 has a first arm portion 533 and a second arm portion 534. Mount portions 541A and 541B are provided on the main surface (XY surface) of the first arm portion 533 and the main surface (XY surface) of the second arm portion 534, respectively.

  In the piezoelectric vibrating piece 500 configured as described above, it is assumed that the conductive adhesive (not shown) applied to the mount portion 541A (541B) wets and spreads in the longitudinal direction (Y-axis direction) of the support arm portion 530. However, since it does not accumulate at the boundary portion 533X and reach the other mount portion 541B (541A) side, a short circuit can be prevented.

(Modification 2 of the second embodiment)
Next, Modification 2 of the second embodiment described above will be described mainly with reference to FIG.
FIG. 9C is a plan view of the piezoelectric vibrating piece according to the second modification of the second embodiment.
As shown in FIG. 9C, the support arm portion 630 constituting the piezoelectric vibrating piece 600 includes an extended arm portion 632 extending from the base portion 410 and a first arm portion formed continuously with the extended arm portion 632. 633, and a second arm portion 634 formed continuously with the first arm portion 633. A mount portion 641A is provided from the main surface (XY surface) of the extended arm portion 632 to the main surface (XY surface) of the first arm portion 433. A mount portion 641B is provided on the main surface (XY surface) of the second arm portion 434.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the embodiment described above, both side surfaces 133S and 133T of the first arm portion 133 and both side surfaces 134S and 134T of the second arm portion 134 are formed in a planar shape, but the present invention is not limited to this. Absent. By forming the side surface of the first arm portion and the side surface of the second arm portion in a curved shape, the first arm portion is formed so that the width gradually decreases toward the tip end side, and the second arm It may be formed such that the width gradually increases as the portion moves toward the tip side.

DESCRIPTION OF SYMBOLS 1 ... Piezoelectric vibrator 2 ... Package 3 ... Package body (base member)
4. Sealing plate (lid member)
DESCRIPTION OF SYMBOLS 100 ... Piezoelectric vibration piece 110 ... Base part 120A, 120B ... Vibrating arm part 130A, 130B ... Support arm part 131 ... Base end arm part 132 ... Extension arm part 133 ... First arm part 134 ... Second arm part 135 ... Tip arm Part 136 ... Inclined arm part 133X ... Boundary parts 141A and 141B ... Mount part C1 ... Cavity E ... Etching residue (deformed part)

Claims (11)

The base,
A pair of vibrating arms extending in a first direction from the base and spaced apart in a second direction intersecting the first direction;
A support arm portion extending in the first direction from the base portion,
The support arm is
In the base portion, extending from between the portions where the vibrating arm portion extends, in the length direction of the vibrating arm portion,
A first arm portion formed such that a width that is a length along the second direction is gradually narrowed toward the distal end side of the support arm portion;
A piezoelectric vibrating piece having a second arm portion extending from the first arm portion in the first direction and having a width that increases toward the tip end side. . The support arm portion has a tip arm portion formed continuously with the second arm portion and extending along the length direction,
The piezoelectric vibrating piece according to claim 1, wherein a mount portion on which a mount electrode is formed is provided on a main surface of the tip arm portion.   2. The piezoelectric vibrating piece according to claim 1, wherein mount portions on which mount electrodes are formed are provided on a main surface of the first arm portion and a main surface of the second arm portion. The support arm includes an extended arm extending from the base, a first arm formed continuously with the extended arm, and a second arm formed continuously with the first arm. And
2. The piezoelectric vibration according to claim 1, wherein a mount portion having a mount electrode is provided from the main surface of the extended arm portion to the first arm portion, and further provided on the main surface of the second arm portion. Piece.   5. The piezoelectric vibrating piece according to claim 1, wherein both side surfaces of the first arm portion and the second arm portion are each formed in a planar shape. The support arm portion has an extended arm portion that extends from the base side, and has a distal end side connected to the base end side of the first arm portion,
6. The piezoelectric vibrating piece according to claim 1, wherein a deformed portion is formed on a base side of a side surface of the extending arm portion. The support arm is
The piezoelectric vibrating piece according to any one of claims 1 to 6, further comprising a tip arm portion extending in the first direction from the second arm portion and having a constant width.   The boundary part of said 1st arm part and said 2nd arm part is located in the said base part side rather than the intermediate position of the said 1st direction in the said support arm part, The Claim 1 to 7 characterized by the above-mentioned. The piezoelectric vibrating piece according to any one of claims. One side surface of the first arm portion and the second arm portion is formed in a planar shape extending in the first direction,
The other side surface of the first arm portion is formed in a flat shape so as to gradually approach the one side surface of the first arm portion as it goes toward the tip end side.
The other side surface of the second arm portion is formed in a flat shape so as to gradually move away from the one side surface of the second arm portion as it goes toward the distal end portion side. The piezoelectric vibrating piece according to any one of the above.   The rate of change along the first direction of the width dimension of the second arm portion is greater than the rate of change along the first direction of the width dimension of the first arm portion. Item 10. The piezoelectric vibrating piece according to any one of Items 1 to 9. A base member;
A lid member that is overlapped and joined to the base member and has a cavity hermetically sealed with the base member;
A piezoelectric vibrator comprising: the piezoelectric vibrating piece according to claim 1 mounted on a mounting surface of the base member and housed in the cavity.

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