Tuning fork-type piezoelectric vibration piece

Abstract

To provide a tuning fork-type piezoelectric vibration piece with a larger strength.SOLUTION: A tuning fork-type piezoelectric vibration piece 2 is in the shape of a tuning fork in plan view, and includes: a base part 20; a pair of vibration arm parts 21, 22 extending from one end side of the base part 20; and a supporting arm part 23 extending from the base part 20. The supporting arm part 23 includes: metal bumps 7a, 7b joined to the container 3; and a thick part 24, the thick part protruding in the thickness direction in the region between the metal bumps 7a, 7b and the base part 20 in plan view. The tuning fork-type piezoelectric vibration piece 2 is equipped in the container 3 and serves as a tuning fork-type piezoelectric vibrator 1.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a tuning-fork type piezoelectric vibrating piece in which a pair of vibrating arms vibrates in a flexural vibration mode. [Background technology]

[0002] Tuning-fork type piezoelectric vibrating pieces have been widely used as frequency generating sources for reference signals for clocks, etc. Such tuning-fork type piezoelectric vibrating pieces are bonded and mounted inside the concave shape of an insulating base (container), and are used as surface-mount tuning-fork type piezoelectric vibrators in which the concave portion is hermetically sealed with a lid.

[0003] As such a tuning fork-type piezoelectric vibrator, a tuning fork-type quartz crystal vibrator has been disclosed that incorporates a three-arm tuning fork-type quartz crystal piece therein, the tuning fork-type quartz crystal piece having first and second vibrating arms extending parallel to each other from a base and a support arm extending from the base between the vibrating arms (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication 2019-165348 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a configuration having supporting arms joined to a tuning-fork type piezoelectric vibrator as described in Patent Document 1, vibrations from the two vibrating arms are concentrated on the supporting arms, and there is a risk that vibration characteristics such as equivalent series resistance value (crystal impedance, CI value) may deteriorate. In other words, a tuning-fork type piezoelectric vibrating piece having supporting arms with improved vibration characteristics has been desired.

[0006] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a tuning-fork type piezoelectric vibrating piece having improved vibration characteristics. [Means for solving the problem]

[0007] The present invention is characterized in that the tuning-fork-type piezoelectric vibrating piece has a tuning fork shape in a planar view and is mounted inside a container to become a piezoelectric vibrator, the tuning fork-type piezoelectric vibrating piece comprising a base, a pair of vibrating arms extending from one end side of the base, and a support arm extending from the base, the support arm having a joint joined to the container and a thick portion that is convex in the thickness direction between the joint and the base in a planar view.

[0008] In other words, the tuning-fork type piezoelectric vibrating piece of the present invention has a thick portion that is convex in the thickness direction between the joint and the base in a plan view. With this configuration, the thick portion can stop the transmission of vibration from the vibrating arm portion, thereby improving the vibration characteristics.

[0009] Furthermore, in the event that an impact is applied to a tuning fork-type piezoelectric vibrator equipped with a tuning fork-type piezoelectric vibrating piece, there is a risk that the supporting arm having a joint may break; however, by improving the physical strength of the supporting arm with the thick portion, it is possible to prevent the supporting arm from breaking.

[0010] The thick portion may be formed so as to protrude from at least the main surface on the back side of the main surface having the joint portion. With such a configuration, it is possible to ensure a sufficient thickness of the thick portion, and to more reliably improve the vibration characteristics.

[0011] The joining member constituting the joining portion may be formed of a bump made of metal. In such a configuration, the tuning-fork-type piezoelectric vibrating piece and the container can be joined by metal bump joining. Furthermore, if the joining is by metal bump joining, the joining strength between the container and the tuning-fork-type piezoelectric vibrating piece can be improved compared to joining by adhesive. Furthermore, although the improved joining strength makes it easier for external impacts to be transmitted to the tuning-fork-type piezoelectric vibrating piece, the tuning-fork-type piezoelectric vibrating piece of the present invention has improved physical strength of the supporting arms, and therefore can prevent the supporting arms from being damaged. Effect of the Invention

[0012] According to the present invention, it is possible to provide a tuning-fork type piezoelectric vibrating piece having improved vibration characteristics. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a top view of a tuning-fork type piezoelectric vibrator according to a first embodiment. [Diagram 2] 2 is a cross-sectional view taken along the line AA of the tuning-fork-type piezoelectric vibrator in the state where it is hermetically sealed with a lid in FIG. 1. [Diagram 3] 1 is a schematic plan view of one main surface of a tuning-fork type piezoelectric vibrating piece according to a first embodiment. [Figure 4] 4 is a cross-sectional view of the tuning-fork type piezoelectric vibrating piece shown in FIG. [Diagram 5] BB cross-sectional view showing a first modified example of the tuning-fork type piezoelectric vibrating piece in FIG. [Figure 6] BB cross-sectional view showing a second modified example of the tuning-fork type piezoelectric vibrating piece in FIG. [Figure 7] FIG. 11 is a schematic plan view of one main surface of a tuning-fork type piezoelectric vibrating piece according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this specification, the description of various electrodes formed on the piezoelectric vibrating piece (tuning fork type piezoelectric vibrating piece) is omitted. Also, the X-axis direction (X-direction) described in each drawing and this specification is the same as the X-axis direction of the crystal axis of the quartz crystal, the Y-axis direction (Y-direction) is the same as the Y-axis direction of the crystal axis of the quartz crystal (or the Y' direction tilted from the Y-axis by several degrees), and the Z-axis direction (Z-direction) is the same as the Z-axis direction of the crystal axis of the quartz crystal (or the Z' direction tilted from the Z-axis by several degrees).

[0015] FIG. 1 is a top view of a tuning-fork type piezoelectric vibrator 1 according to the first embodiment, and FIG. 2 is a cross-sectional view taken along line AA of the tuning-fork type piezoelectric vibrator 1 in FIG. 1 in a state where it is hermetically sealed with a lid 4. As shown in FIG. In this specification, the depth direction in FIG. 1 is the bottom side of tuning fork type piezoelectric vibrator 1, and the front direction is the top side of tuning fork type piezoelectric vibrator 1, and the bottom and top are described.

[0016] The tuning fork type piezoelectric vibrator 1 (quartz crystal vibrator 1) in the first embodiment (present embodiment) is a surface mount type quartz crystal vibrator having a package structure of a substantially rectangular parallelepiped shape. The external dimensions of the quartz crystal vibrator 1 are not particularly limited, and may be any of various known dimensions depending on the application.

[0017] 2, in the quartz crystal resonator 1 according to this embodiment, a tuning-fork type piezoelectric vibrating piece 2 (quartz crystal vibrating piece 2) is accommodated in a recess 5 of a container 3 made of an insulating material, and then a flat lid 4 is bonded to the open end of the container 3 so as to cover the recess 5, thereby hermetically sealing the quartz crystal vibrating piece 2 in the internal space. The container 3 and the lid 4 are bonded together via a sealing material (not shown).

[0018] The container 3 is a box-shaped body made of an insulating material mainly composed of ceramic such as alumina, and is formed by, for example, stacking three ceramic green sheets and sintering them together to form a bottom layer 3a, a middle layer 3b, and an upper layer 3c. In this embodiment, of the bottom layer 3a, the middle layer 3b, and the upper layer 3c, the rectangular frame-shaped middle layer 3b is stacked on the bottommost layer 3a, and the rectangular frame-shaped upper layer 3c is stacked on the middle layer 3b. Therefore, the container 3 has a rectangular recess 5 in plan view, with the upper surface of the bottom layer 3a as the bottom surface and the middle layer 3b and the upper layer 3c as the frame-shaped bank portion 30. The middle layer 3b protrudes toward the recess 5 on the upper surface of the bottom layer 3a, and a part of it forms a step portion 31 on which the quartz crystal vibrating piece 2 is mounted. A sealing material (not shown) is formed in a frame shape in a plan view on the upper surface 300 of the bank portion 30 (upper layer portion 3c).

[0019] The step 31 forms an edge 32 as an end face in a direction protruding toward the recess 5 in a plan view. The step 31 in this embodiment is formed from near the center of the short side of the container 3 in a plan view and protrudes toward the recess 5, and has a substantially rectangular shape with a uniform width with the protruding direction as the longitudinal direction in a plan view. The step 31 also has two mounting pads 6a, 6b on the upper surface thereof that are conductively bonded to the crystal vibrating piece 2. The mounting pads 6a, 6b are formed in parallel with a gap between them, and are connected to the metal bumps 7a, 7b of the tuning fork type piezoelectric vibrating piece 2 by bump bonding, respectively. That is, the mounting pads 6a, 6b correspond to the mounting portion in the present invention. In this embodiment, the mounting pads 6a, 6b are arranged in parallel in the long side direction of the container 3 in a plan view (the longitudinal direction of the step 31), but the width of the step 31 may be formed to be sufficiently large and arranged in parallel in the short side direction of the container 3 in a plan view. The two mounting pads 6a, 6b have opposite polarities and are electrically connected to a plurality of external connection terminals 8 provided on the outer bottom surface of the container 3 through internal wiring and vias (not shown).

[0020] In this embodiment, the two mounting pads 6a and 6b are formed by laminating nickel and gold in this order on the upper surface of a tungsten metallization layer using a method such as plating. Note that molybdenum may be used as the metallization layer instead of tungsten.

[0021] The lid 4 may be, for example, a metal lid body having a rectangular shape in plan view and made of Kovar as a base. Also, for example, the lid 4 may be configured such that a brazing material made of metal is formed in a circumferential shape on a nickel-plated layer on the outer periphery of the joint surface side with the container 3. Furthermore, the joint between the lid 4 and the container 3 may be made by brazing or seam welding.

[0022] FIG. 3 is a schematic plan view of one main surface side of the tuning-fork type piezoelectric vibrating piece 2 according to the embodiment of the present invention. For ease of explanation, of the two opposing main surfaces of the quartz crystal vibrating piece 2, the main surface that faces the mounting pads 6a, 6b when mounted on the container 3 will be referred to as the back surface, and the main surface opposite the back surface will be referred to as the front surface. That is, Fig. 3 is a plan view of the quartz crystal vibrating piece 2 as seen from the front surface side.

[0023] The quartz crystal vibrating piece 2 is a thin-plate-shaped quartz crystal Z plate having a thickness in the Z direction. The quartz crystal vibrating piece 2 includes a base 20, a pair of vibrating arms 21, 22 formed side by side from one end side of the base 20 and protruding (extending) in the Y direction (first direction), and a support arm 23 formed protruding in the Y direction (the same direction as the vibrating arms 21, 22) from between the pair of vibrating arms 21, 22 at one end side of the base 20. Therefore, the quartz crystal vibrating piece 2 is a tuning fork-shaped piezoelectric vibrating piece having a tuning fork shape in a plan view, and is formed into a three-arm shape by the support arm 23 extending in the same direction as the longitudinal vibrating arms 21, 22 and the pair of vibrating arms 21, 22. In this embodiment, the vibrating arms 21, 22 and the support arm 23 are formed to extend in the +Y direction, but may be formed to extend in the -Y direction.

[0024] The shape of the quartz crystal vibrating piece 2 of this embodiment (the vibrating arms 21, 22, base 20, and support arms 23 that constitute the quartz crystal vibrating piece 2) is formed, for example, by wet etching a quartz crystal blank (not shown), which is a quartz crystal piece made of anisotropic material.

[0025] In this embodiment, the base 20 has a shape that is symmetrical (symmetrical in the X direction) in a plan view. The base 20 is formed to be wider (longer in the X direction) than the vibrating arms 21, 22 and the supporting arm 23. The side of the base 20 is formed to be gradually narrower from the vibrating arms 21, 22 side to the other end side. The base 20 may have one or more through holes penetrating in the Z direction. Such a configuration having through holes can ensure the conduction of the extraction electrodes described later. In addition, the mechanical vibration of the tuning fork vibrating arm part during operation can be efficiently attenuated and the propagation of the vibration to the supporting arm 23 can be suppressed, thereby reducing acoustic leakage and lowering the series resonance resistance (equivalent series resistance value, crystal impedance, CI value).

[0026] The pair of vibrating arms 21, 22 are formed continuously from the base 20. The pair of vibrating arms 21, 22 are formed with narrow parts 214, 224 that are gradually narrower from the base 20, long parts 215, 225 that are formed continuously from the narrow parts 214, 224 and have a uniform width, wide parts 212, 222 that are further formed continuously from the long parts 215, 225 and gradually widen toward the tip side, and wide parts 211, 221 (weight parts) that are further formed continuously from the wide parts 212, 222 and are wider than the width of the long parts 215, 225 (the arm dimension in the second direction of the long parts 215, 225). That is, the wide parts 211, 221 form the tip parts of the vibrating arms 21, 22 in the second direction (X direction). The corners on the tip side of each of the wide portions 211, 221 are chamfered. The vibrating arms 21, 22 have a pair of main surfaces facing each other in the Z direction and a pair of side surfaces facing each other in the X direction.

[0027] A long groove is formed on the main surface of the pair of vibrating arms 21 and 22 in order to further reduce the equivalent series resistance value (Crystal Impedance, CI value). More specifically, a long groove 213 is formed on the front main surface (front surface) of the vibrating arm 21, and a long groove (not shown) is formed on the back main surface (back surface) of the vibrating arm 21, so that the long grooves are formed to face each other. In addition, a long groove 223 is formed on the front main surface (front surface) of the vibrating arm 22, and a long groove (not shown) is formed on the back main surface (back surface) of the vibrating arm 22, so that the long grooves are formed to face each other. The long grooves 213 and 223 formed on the front surface of each of the vibrating arms 21 and 22 and the long groove (not shown) formed on the back surface are formed with a predetermined depth (length in the Z direction) and width (length in the X direction) on the front and back main surfaces of each of the vibrating arms 21 and 22. Moreover, one end of each long groove in the Y direction is formed up to the region of the base 20, and the other end is formed at the boundary between the long portions 215, 225 and the widened portions 212, 222. That is, all the long grooves have a longitudinal direction along the direction in which the vibrating arms 21, 22 protrude (first direction, Y direction) and a width direction along the direction in which the vibrating arms 21, 22 are arranged side by side (second direction, X direction). Moreover, an excitation electrode (not shown) described later is formed inside each long groove. Moreover, each long groove is formed by wet etching.

[0028] The supporting arm 23 is formed so as to protrude in the Y direction from one end side of the base 20 (the side from which the vibrating arms 21 and 22 protrude). That is, the supporting arm 23 is formed so as to protrude in the first direction from one end side of the base 20. It is preferable that the supporting arm 23 is disposed at equal intervals with respect to each of the vibrating arms 21 and 22. That is, it is preferable that the supporting arm 23 is formed so as to protrude from the exact center of the protruding positions of the two vibrating arms 21 and 22 on the base 20. Moreover, the supporting arm 23 in this embodiment has a substantially rectangular shape having a uniform width with the first direction as the longitudinal direction.

[0029] The support arm 23 has a metal bump 7b on the back side near the tip end extending in the longitudinal direction (first direction), and a metal bump 7a on the back side on the base 20 side as viewed from the metal bump 7b. The metal bumps 7a and 7b are plated bumps formed by electrolytic plating. The metal bump 7a is bonded to the mounting pad 6a of the container 3 when the quartz crystal vibrating piece 2 is mounted on the container 3, and the metal bump 7b is bonded to the mounting pad 6b. That is, the metal bumps 7a and 7b correspond to the bonding portion in the present invention, and the bonding portion is composed of the metal bump. In this embodiment, the metal bump 7b is provided at the tip end of the support arm 23, but is not limited thereto. For example, the metal bump 7b may be provided near the center of the support arm 23 in the first direction, or may be provided at a position further toward the base 20 side from the center. Also, as long as the multiple metal bumps are bonded to both of the mounting pads 6a, 6b (mounting portions) of the container 3, the positions, shapes, and number of the metal bumps on the support arm 23 are not particularly limited. That is, the metal bumps 7a, 7b in this embodiment are elliptical and of the same size, but the shapes of the metal bumps 7a, 7b are not particularly limited and may be of various shapes, and the metal bumps 7a and 7b may be different in size or shape from each other. Also, in this embodiment, the support arm 23 is configured to have two metal bumps 7a, 7b, but it is sufficient that the support arm 23 has multiple (two different polarity) metal bumps, and may have three or more metal bumps.

[0030] Figure 4 is a B-B cross-sectional view of the tuning-fork-type piezoelectric vibrating piece 2 in Figure 3, Figure 5 is a B-B cross-sectional view showing a first modified example of the tuning-fork-type piezoelectric vibrating piece in Figure 3, and Figure 6 is a B-B cross-sectional view showing a second modified example of the tuning-fork-type piezoelectric vibrating piece in Figure 3. Moreover, the support arm 23 has a thick portion 24 formed between the metal bumps 7a, 7b and the base 20 in a plan view, which is thicker in the thickness direction than other regions of the support arm 23. That is, the support arm 23 has a shape that protrudes in the thickness direction at a predetermined position between the metal bumps 7a, 7b and the base 20. The thick portion 24 is the portion of the quartz crystal vibrating piece 2 that is formed to be the thickest. Furthermore, the height of the thick portion 24 protruding in the thickness direction is not particularly limited, but is preferably 30% or more, and more preferably 50% or more, of the thickness of the portion of the support arm 23 excluding the thick portion 24. Furthermore, the thick portion 24 is preferably formed to both ends of the support arm 23 in the width direction (X direction). As shown in Fig. 3, the thick portion 24 in this embodiment protrudes from the surface (front surface) opposite to the surface on which the metal bumps 7a, 7b are provided, but the protruding direction in the thickness direction is not particularly limited as long as it is formed at a predetermined position between the metal bumps 7a, 7b and the base 20. For example, as shown in Fig. 5, the thick portion 24 may have a shape protruding from the back surface side (the side on which the metal bumps 7a, 7b are provided), or as shown in Fig. 6, the thick portion 24 may have a shape protruding from both the back surface side and the front surface side. It is preferable that the thick portion 24 is formed so as to protrude from at least the surface that faces the step portion 31 when mounted on the container 3 (the surface on which the metal bumps 7a, 7b are provided).

[0031] In this embodiment, the thick portion 24 is formed integrally with the support arm 23. Such a thick portion 24 can be formed at the same time as forming the shape of the quartz crystal vibrating piece 2 by wet etching, for example. The thick portion 24 may also be formed by adding it to the main surface of the quartz crystal vibrating piece 2 that has already been formed by wet etching or the like. In this case, the addition added as the thick portion 24 is made of an insulating material. Examples of such insulating materials that can be used include quartz crystal, silicate compounds other than quartz crystal, and resin compositions such as epoxy resin.

[0032] In addition, the quartz crystal vibrating piece 2 is formed with a first excitation electrode and a second excitation electrode configured with different potentials, and an extraction electrode drawn from each of the first excitation electrode and the second excitation electrode via a wiring electrode. The first excitation electrode is formed on the front and back main surfaces including the inner circumferential surface of the long groove of one vibrating arm 21, and on the outer and inner surfaces of the other vibrating arm 22 via the wiring electrode. Similarly, the second excitation electrode is formed on the front and back main surfaces including the inner circumferential surface of the long groove of the other vibrating arm 22, and on the outer and inner surfaces of one vibrating arm 21 via the wiring electrode. The extraction electrode drawn from the first excitation electrode is connected to the metal bump 7b via the surface of the base 20 and the support arm 23, and the extraction electrode drawn from the second excitation electrode is connected to the metal bump 7a via the surface of the base 20 and the support arm 23. Note that illustration of each electrode pattern is omitted in each drawing.

[0033] The quartz crystal vibrating piece 2 is mounted on the container 3 by bonding the metal bumps 7a, 7b of the quartz crystal vibrating piece 2 to the mounting pads 6a, 6b. The metal bumps 7a, 7b and the mounting pads 6a, 6b are conductively bonded to each other by FCB (Flip Chip Bonding). That is, the quartz crystal vibrating piece 2 is bonded and mounted on the container 3 by bumps made of metal plating (plated bumps). Note that in this embodiment, bump bonding is performed using plated bumps, but bump bonding using stud bumps may also be used.

[0034] With the above configuration, it is possible to provide a tuning-fork type piezoelectric vibrating piece with improved vibration characteristics. The tuning-fork type piezoelectric vibrating piece 2 (quartz crystal vibrating piece 2) of the present invention is configured such that the supporting arm 23 has a thick portion 24 that is convex in the thickness direction between the metal bumps 7a, 7b and the base 20 in a plan view. With this configuration, the propagation of vibration from the vibrating arms 21, 22 can be stopped by the thick portion 24, thereby improving the vibration characteristics.

[0035] Furthermore, in the event of an impact being applied to tuning-fork-type piezoelectric vibrator 1 equipped with quartz crystal vibrating piece 2, there would normally be a risk of support arm 23 having metal bumps 7a, 7b joined to container 3 breaking; however, the thick portion 24 can improve the physical strength of support arm 23, thereby preventing support arm 23 from breaking.

[0036] Furthermore, in the quartz crystal vibrating piece 2 of the present invention, the thick portion 24 is formed so as to protrude (be convex) from the surface opposite to the surface having the metal bumps 7a, 7b in the thickness direction. With this configuration, it is possible to ensure a sufficient thickness of the thick portion 24, and to more reliably improve the vibration characteristics. Furthermore, when the quartz crystal vibrating piece 2 is mounted in the container 3 to form the tuning fork type piezoelectric vibrator 1, even if the tuning fork type piezoelectric vibrator 1 receives an impact from the outside, it is possible to prevent the internal quartz crystal vibrating piece 2 from vibrating and causing the thick portion 24 to come into contact with the container 3.

[0037] Furthermore, in the quartz crystal vibrating piece 2 of the present invention, the thick portion 24 protrudes in the thickness direction by 30% or more of the thickness of the portion of the supporting arm 23 excluding the thick portion 24. With this configuration, it is possible to ensure a sufficient thickness of the thick portion 24, and it is possible to more reliably improve the vibration characteristics.

[0038] Furthermore, in the quartz crystal vibrating piece 2 of the present invention, the supporting arms 23 are formed to both ends in the width direction (X direction). With this configuration, when vibrations generated in the vibrating arms 21 and 22 try to propagate to the metal bumps 7a and 7b, they must pass through the thick portion 24, so that the vibration damping effect of the thick portion 24 can be more reliably achieved. Furthermore, when vibrations are generated due to an external impact on the container 3, they propagate from the metal bumps 7a and 7b to the quartz crystal vibrating piece 2, but when the vibrations try to propagate to the vibrating arms 21 and 22, they must pass through the thick portion 24, so that the vibration damping effect of the thick portion 24 can be more reliably achieved.

[0039] In addition, in the crystal vibrating piece 2 of the present invention, the bonding member constituting the bonding portion bonded to the container 3 is formed of metal plated bumps (metal bumps 7a, 7b). With this configuration, the support arm 23 and the step portion 31 of the container 3 are bonded (bump bonded) by bumps made of metal plating, and the bonding strength between the container 3 and the crystal vibrating piece 2 can be improved compared to bonding by adhesive. In addition, by improving the bonding strength, external impacts tend to be concentrated and transmitted to the support arm 23 where the metal bumps 7a, 7b of the crystal vibrating piece 2 are provided. However, in the crystal vibrating piece 2 of the present invention, the physical strength of the support arm 23 is improved by the thick portion 24, so that the crystal vibrating piece 2 can be prevented from breaking (breakage, destruction). More specifically, the bump bonding shown in this embodiment can firmly bond the container and the crystal vibrating piece. That is, it is a configuration that can be bonded electrically and mechanically firmly and stably. On the other hand, there is a concern that the cushioning function of the bonding material is less effective than when an adhesive is used as the bonding material, and impact resistance is reduced. The structure of the present invention can achieve stable and strong bonding electrically and mechanically, and can also improve impact resistance. Note that the adhesive referred to here is, for example, a conductive resin adhesive containing a conductive material such as a metal filler.

[0040] It should be noted that the present invention is not limited to the configurations of the above-described embodiments, and many other embodiments can be obtained. FIG. 7 is a schematic plan view of one main surface of a tuning-fork type piezoelectric vibrating piece according to the second embodiment. In the second embodiment, only the arrangement and shape of the support arm portion 23 of the quartz crystal vibrating piece 2 differs from that of the first embodiment. Since the other configurations are similar to the corresponding configurations of the first embodiment, detailed explanations are omitted.

[0041] The quartz crystal vibrating piece 102 is a thin-plate-shaped quartz crystal Z plate having a thickness in the Z direction. The quartz crystal vibrating piece 102 includes a base 120, a pair of vibrating arms 121 and 122 formed side by side from one end of the base 120 and protruding (extending) in the Y direction (first direction), and a support arm 123 formed protruding in the -Y direction (opposite the vibrating arms 121 and 122) from the other end opposite the one end of the base 120. The support arm 123 protrudes in the -Y direction from the other end opposite the one end of the base 120, and further protrudes in the X direction near its tip. Therefore, the quartz crystal vibrating piece 2 is a tuning fork-type piezoelectric vibrating piece having a tuning fork shape in a plan view, and the end opposite the vibrating arms 121 and 122 in the longitudinal direction is formed into a substantially L-shape by the support arm 123 in a plan view. In this embodiment, the vibrating arms 121 and 122 are formed to extend in the +Y direction, but may be formed to extend in the -Y direction. Also, in this embodiment, the supporting arm 123 is formed to protrude in the +X direction, but may be formed to protrude in the -X direction.

[0042] The supporting arm 123 has a metal bump 107b on one main surface side of one end (the end in the +X direction in this embodiment) protruding in the X direction, and has a metal bump 107a on the other end (the end in the -X direction in this embodiment) as viewed from the metal bump 107b. The supporting arm 123 has a thick portion 124 formed to be thicker in the thickness direction than other regions of the supporting arm 123 between the metal bumps 107a, 107b and the base 120 in a plan view. That is, the supporting arm 123 has a shape protruding in the thickness direction at a predetermined position between the metal bumps 107a, 107b and the base 120.

[0043] The quartz crystal vibrating piece 102 can be mounted inside a container (not shown) to form a tuning-fork type piezoelectric vibrator, similar to the quartz crystal vibrating piece 2. In this case, the container in which the quartz crystal vibrating piece 102 is mounted has a configuration corresponding to the step portion 31 and mounting pads 6a, 6b in the first embodiment. The arrangement and shape of each component of the container are appropriately set to correspond to the metal bumps 107a, 107b of the quartz crystal vibrating piece 102. Even with the configuration of the second embodiment, it is possible to obtain the same effects as those of the first embodiment.

[0044] The embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present invention is not interpreted solely by the above-described embodiments, but is defined by the claims. Also, all modifications within the scope and meaning equivalent to the claims are included. [Industrial Applicability]

[0045] The tuning-fork-type piezoelectric vibrating piece of the present invention can be used in the industry of manufacturing and selling tuning-fork-type piezoelectric vibrators in which the tuning-fork-type piezoelectric vibrating piece of the present invention is mounted inside a container. [Explanation of symbols]

[0046] 1...Tuning fork type piezoelectric vibrator 2...Piezoelectric vibrating piece 20…Base 21, 22... Vibrating arm 23...Support arm 24...Thick wall part 3…Container 31...Double part 6a, 6b...Mounting pad 7a, 7b...Metal bumps

Claims

1. A tuning-fork type piezoelectric vibrating piece having a tuning fork shape in a plan view and mounted inside a container to become a piezoelectric vibrator, A base and A pair of vibrating arms extending from one end side of the base portion; a support arm extending from the base; The support arm portion is a joint joined to the container; A thick portion that is convex in a thickness direction between the joint portion and the base portion in a plan view. Tuning fork type piezoelectric vibrating piece.

2. The thick portion is The joint is formed so as to protrude from at least the main surface on the back side of the main surface having the joint portion.

2. The tuning-fork type piezoelectric vibrating piece according to claim 1.

3. The bonding member constituting the bonding portion is formed of a bump made of metal.

3. The tuning-fork type piezoelectric vibrating piece according to claim 1.

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