Piezoelectric vibration element and manufacturing method of piezoelectric vibrator

Abstract

To provide a piezoelectric vibration element bonded to a mount part in the package in a state where both of a mechanical bonding strength and a stable electric connection performance are achieved, and provide a manufacturing method of a piezoelectric vibrator, having the piezoelectric vibration element.SOLUTION: A piezoelectric vibration element that is housed in a package 110, and is bonded to a mount part 120 in the package 110 via a conductive adhesive agent 40, contains: a support part 30 that is bonded to the mount part 120 by the conductive adhesive agent 40; a vibration part 20 that is continued from the support part 30, and in which an excitation electrode is formed; and an electrode part 35 that is provided to an opposite surface to the mount part 120 in the support part 30. The electrode part 35 includes: an adhesive agent arrangement region 36 to which the conductive adhesive agent 40 is arranged; and a plurality of groove parts 37 that is scattered and arranged along an edge 36a of the adhesive agent arrangement region 36. Each of the plurality of groove parts 37 is arranged so as to cross the edge 36a of the adhesive agent arrangement region 36.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a piezoelectric vibration element and a method for manufacturing a piezoelectric vibrator. [Background technology]

[0002] Conventionally, a piezoelectric vibrator is known in which a piezoelectric vibration element is housed inside a package made of ceramic and sealed with a lid. The piezoelectric vibration element is, for example, bonded to a mount in the package, and is electrically connected to a circuit element that converts vibrations generated by the piezoelectric vibration element into an electrical signal to realize a predetermined function (for example, a clock, a calendar, etc.). Here, the piezoelectric vibration element may be bonded to an electrode pad on the mount via a conductive adhesive in which conductive filler is dispersed in a binder resin. Patent Document 1 discloses a piezoelectric vibration element in which a joint having a plurality of pinholes is bonded to an electrode pad via a conductive adhesive. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-320297 A Summary of the Invention [Problem to be solved by the invention]

[0004] When target parts are joined together with a conductive adhesive, the mechanical joint strength can be improved by the anchor effect by forming multiple pinholes at the joint as in the above-mentioned Patent Document 1. However, in a piezoelectric vibration element having holes or recesses for obtaining the anchor effect of pinholes or the like, in addition to the above-mentioned mechanical joint strength, stable electrical connection performance due to the conductive filler is also desired.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a piezoelectric vibration element that is joined to a mounting portion of a package in a state that achieves both mechanical bonding strength and stable electrical connection performance, and a method for manufacturing a piezoelectric vibrator that includes such a piezoelectric vibration element. [Means for solving the problem]

[0006] The piezoelectric vibration element of the present invention is a piezoelectric vibration element that is contained in a package and joined to a mounting portion in the package via a conductive adhesive, and includes a support portion that is joined to the mounting portion by the conductive adhesive, a vibration portion that is continuous from the support portion and has an excitation electrode formed thereon, and an electrode portion provided on the support portion's opposing surface facing the mounting portion, wherein the electrode portion has an adhesive placement area in which the conductive adhesive is placed, and a plurality of groove portions distributed along the edge of the adhesive placement area, and each of the plurality of groove portions is arranged across the edge of the adhesive placement area.

[0007] The manufacturing method of a piezoelectric vibrator of the present invention is a manufacturing method of a piezoelectric vibrator in which the electrode portion of the support portion in the piezoelectric vibration element of the present invention is joined via a conductive adhesive that adheres to both the electrode portion and the mounting portion, and the conductive adhesive that adheres to the electrode portion side is arranged in the adhesive arrangement area. Effect of the Invention

[0008] According to the present invention, it is possible to provide a piezoelectric vibration element that is joined to a mounting portion of a package in a state in which both mechanical joining strength and stable electrical connection performance are achieved, and a method for manufacturing a piezoelectric vibrator that includes such a piezoelectric vibration element. [Brief description of the drawings]

[0009] [Figure 1] 1 is an exploded perspective view showing a schematic diagram of a piezoelectric vibrator including a piezoelectric vibration element according to an embodiment; [Diagram 2] 1 is a plan view of a piezoelectric vibration element according to an embodiment. [Diagram 3]10 is a back view of a tip joint portion of a support portion of the piezoelectric vibration element according to the embodiment that is joined to a mount portion. FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. [Diagram 5] 4 is a cross-sectional view (XZ cross-sectional view) that illustrates a state in which a tip joint portion of a support portion of the piezoelectric vibration element according to the embodiment is joined to a mount portion of a package. FIG. [Figure 6] 6 is a cross-sectional view taken along line VI-VI of FIG. 5. [Figure 7] FIG. 4 corresponds to FIG. 3 and shows a groove according to Modification 1. [Figure 8] FIG. 4 is a view corresponding to FIG. 3 and shows a groove according to Modification 2. [Figure 9] FIG. 4 corresponds to FIG. 3 and shows a groove according to Modification 3. [Figure 10A] 4 is a micrograph showing a groove portion of a piezoelectric vibration element according to an example. [Figure 10B] FIG. 10B is a mapping image of Ag (silver) based on the micrograph of FIG. 10A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments will be described with reference to the drawings. Fig. 1 is an exploded perspective view that shows a piezoelectric vibrator 100 including a piezoelectric vibration element 1 according to an embodiment. Fig. 2 is a plan view of the piezoelectric vibration element 1.

[0011] 1, the piezoelectric vibrator 100 includes a package 110 and a piezoelectric vibration element 1 housed in the package 110. The package is made of a material such as ceramic or glass and has a rectangular box shape, and has a housing recess 111 that opens upward in the figure. The piezoelectric vibration element 1 is housed in the housing recess 111, and the housing recess 111 is sealed with a lid (not shown).

[0012] The package 110 has a pair of mounts 120 in the accommodation recess 111. The piezoelectric vibration element 1 is supported by the pair of mounts 120. Each of the pair of mounts 120 is disposed on either side of the bottom of the accommodation recess 111 in the width direction, and in the center in the longitudinal direction. The mounts 120 are formed of convex parts protruding from the bottom, and electrode pads 121 are disposed on the upper surface of the mounts 120. The piezoelectric vibration element 1 is electrically connected to these electrode pads 121. The vibrations generated by the piezoelectric vibrator 1 are converted into electrical signals by circuit elements (not shown) electrically connected via the electrode pads 121, thereby realizing a predetermined function (e.g., a clock, a calendar, etc.).

[0013] The piezoelectric vibration element 1 includes a substrate 10 and an excitation electrode (not shown) formed on the surface of the substrate 10. The piezoelectric vibration element 1 of the embodiment is a quartz vibration element in which the substrate 10 is a thin quartz crystal piece. The substrate 10 is formed by processing a quartz crystal plate cut at a predetermined cut angle into a tuning fork shape of a predetermined shape in an orthogonal coordinate system of a raw quartz crystal with the electric axis as the X-axis, the mechanical axis as the Y-axis, and the optical axis as the Z-axis. The material of the substrate 10 is not limited to the quartz crystal piece, and other materials such as ceramic pieces may be used.

[0014] 1 and 2 show an XYZ orthogonal coordinate system corresponding to the above-mentioned X-axis, Y-axis, and Z-axis. In addition, in Fig. 2, one side (upper side) in the Y-axis direction is indicated by an arrow Y1, and the other side (lower side) is indicated by an arrow Y2. In addition, in Fig. 2, one side (left side) in the X-axis direction is indicated by an arrow X1, and the other side (right side) is indicated by an arrow X2.

[0015] As shown in FIG. 2, the piezoelectric vibration element 1 of the embodiment is a plate-shaped member that is generally rectangular in plan view and has a symmetrical shape when the X-axis direction is taken as the left-right direction. The piezoelectric vibration element 1 includes a base 13, a pair of vibration parts 20 that generate bending vibration, and a pair of support parts 30 that are arranged on both sides of the pair of vibration parts 20 in the X-axis direction. The pair of vibration parts 20 includes a first vibration arm 21 and a second vibration arm 22 that are adjacent to each other in the X-axis direction. The pair of support parts 30 includes a first support arm 31 adjacent to the X1 side of the first vibration arm 21 and a second support arm 32 adjacent to the X2 side of the second vibration arm 22. The first support arm 31, the first vibration arm 21, the second vibration arm 22, and the second support arm 32 are arranged in parallel at equal intervals in this order from the X1 side to the X2 side and extend in the Y-axis direction.

[0016] Each of the first vibrating arm 21 and the second vibrating arm 22 extends from the end of the base 13 on the Y1 side to the Y1 side. The first vibrating arm 21 and the second vibrating arm 22 have the same length (dimension in the Y-axis direction). The first vibrating arm 21 and the second vibrating arm 22 have a shape in which the width on the Y1 side (dimension in the X-axis direction) is larger than the width on the Y2 side. On the Y2 side of the base 13 opposite to the side on which the vibrating arms 21 and 22 extend, a pair of relay parts, the first relay part 15A and the second relay part 15B, are formed via a constriction part 14 continuing to the base 13 and extending in the X-axis direction. The first support arm 31 extends from the end of the first relay part 15A on the X1 side to the Y1 side. The second support arm 32 extends from the end of the second relay part 15B on the X2 side to the Y1 side. The first vibrating arm 21 is continuous to the first supporting arm 31 via the base 13, the constricted portion 14, and the first relay portion 15A. The second vibrating arm 22 is continuous to the second supporting arm 32 via the base 13, the constricted portion 14, and the second relay portion 15B.

[0017] The first support arm 31 and the second support arm 32 have the same length (dimension in the Y-axis direction) and extend to near the middle of the length of each of the vibrating arms 21, 22. The first support arm 31 and the second support arm 32 have the same width (dimension in the X-axis direction) and are uniform.

[0018] The excitation electrodes (not shown) formed on the surface of the substrate 10 include a first excitation electrode provided on the first vibrating arm 21 and a second excitation electrode provided on the second vibrating arm 22. The first excitation electrode and the second excitation electrode 52 have different polarities. The first excitation electrode is electrically connected to an electrode section 35 (described later) arranged on the first support arm 31 side via a first wiring section (not shown) arranged across the base 13, the constricted section 14, the first relay section 15A, and the first support arm 31. The second excitation electrode is electrically connected to an electrode section 35 (described later) arranged on the second support arm 32 side via a second wiring section (not shown) arranged across the base 13, the constricted section 14, the second relay section 15B, and the second support arm 32.

[0019] In the piezoelectric vibration element 1 of the embodiment, the tip joint 38 of the first support arm 31 is joined to one of the mount parts 120 and supported in the above-mentioned package 110, and the tip joint 38 of the second support arm 32 is joined to the other mount part 120 and supported. As a result, the first excitation electrode is electrically connected to each of the electrode pads 121 of each mount part 120 via the above-mentioned first wiring part, and the second excitation electrode is electrically connected via the second wiring part. The tip joint 38 of each support arm 31, 32 is supported by the mount part 120, and each vibrating arm 21, 22 is in a free state. As a result, the impact received by the package 110 is not easily transmitted directly to each vibrating arm 21, 22, and the leakage of the tuning fork vibration generated in these vibrating arms 21, 22 is suppressed.

[0020] FIG. 3 shows the back side of the tip joint 38 of the first support arm 31 joined to the mount 120, that is, the surface side facing the electrode pad 121 of the mount 120. FIG. 3 shows the Y1 direction and the Y2 direction shown in FIG. 2. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. Hereinafter, the configuration of the tip joint 38 of the first support arm 31 will be described. The tip joint 38 of the second support arm 32 also has a common configuration with the first support arm 31. Therefore, the tip joint 38 of the first support arm 31 will be described as a representative, and the description of the second support arm 32 will be omitted. Hereinafter, the first support arm 31 and the second support arm 32 will be described as a common part, so that these support arms 31 and 32 may be collectively referred to as the support 30.

[0021] 3 and 4, an electrode portion 35 is provided on the surface of the substrate 10 that faces the mount portion 120 of the tip joint portion 38. The electrode portion 35 has an adhesive placement region 36 in which a conductive adhesive 40 (described later) is placed, and a plurality of groove portions 37.

[0022] The electrode portion 35 is formed on the outer surface of the substrate 10 and also on the inner surface of each groove portion 37. The electrode portion 35 is a conductive film made of a conductive metal, and is formed on the substrate 10 by a thin film forming means such as vapor deposition or sputtering. The adhesive placement area 36 is an area in the electrode portion 35 where the conductive adhesive 40 is placed, and is disposed in the center of the electrode portion 35. The adhesive placement area 36 has a circular shape. Therefore, an edge 36a of the adhesive placement area 36 has a circular shape. In the illustrated example, the shape of the adhesive placement area 36 is circular in order to clearly show the shape of the adhesive placement area 36, ​​but the shape of the adhesive placement area 36 is not limited to a circular shape.

[0023] After groove processing is performed on the surface of the substrate 10, the electrode portion 35 is formed, thereby forming a groove portion 37 with the electrode portion 35 formed on the inner surface. The multiple groove portions 37 are distributed and disposed along the edge 36a of the adhesive placement area 36. Each groove portion 37 is an elongated slit, and is all disposed across the edge 36a of the adhesive placement area 36.

[0024] The grooves 37 in the embodiment are disposed at two locations, on the Y1 side and the Y2 side of the center of the adhesive placement area 36. At each location, two grooves 37 are formed, that is, in pairs. The pair of grooves 37 are parallel to each other and extend linearly parallel to the extension direction of the support part 30.

[0025] Each groove 37 extends in two directions, the inner direction and the outer direction of the edge 36a of the adhesive placement area 36. The dimensions of the groove 37 are, for example, about 10 μm in width and about 25 μm in depth, but are not limited to these. The length of the groove 37 is, for example, about 60 μm, but is not particularly limited as long as it has a length extending inward and outward of the edge 36a of the adhesive placement area 36, ​​and may be set appropriately depending on the size of the adhesive placement area 36.

[0026] Fig. 5 is a cross-sectional view showing a state in which the tip joint 38 of the support part 30 of the piezoelectric vibration element 1 is joined to the mount part 120, and shows the XZ cross section of the joint part in Fig. 1. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5. As shown in Figs. 5 and 6, the tip joint 38 of the piezoelectric vibration element 1 is joined to the mount part 120 via a conductive adhesive 40.

[0027] The conductive adhesive 40 is an adhesive in which conductive filler 42, which contributes to conductivity, is dispersed in binder resin 41, which contributes to adhesion. The binder resin 41 is a silicone resin, an epoxy resin, or the like, and accounts for more than approximately 20% of the entire conductive adhesive 40. The conductive filler 42 is Ag (silver) or the like, and accounts for more than 70% of the entire conductive adhesive 40. The conductive filler 42 is a chip-like, thin, flat filler, and the average particle diameter is preferably about 5 μm or more and 20 μm or less.

[0028] As shown in FIG. 5 and FIG. 6, the conductive adhesive 40 is interposed between the electrode portion 35 of the support portion 30 and the electrode pad 121 of the mount portion 120. As a result, the electrode portion 35 is electrically connected to the electrode pad 121. In this state, the piezoelectric vibration element 1 is electrically connected to the circuit element described above. In this manner, when bonding the support portion 30 of the piezoelectric vibration element 1 to the mount portion 120, the conductive adhesive 40 in a liquid state (the binder resin 41 is liquid) before hardening is applied to, for example, the electrode pad 121 of the mount portion 120, and the tip joint portion 38 is pressed against the mount portion 120 with the electrode portion 35 facing the conductive adhesive 40. The conductive adhesive 40 is hardened, and the support portion 30 of the piezoelectric vibration element 1 is bonded to the mount portion 120 of the package 110.

[0029] When the tip joint 38 of the piezoelectric vibration element 1 is joined to the mount section 120 of the package 110 as described above, the liquid conductive adhesive 40 adheres to the adhesive placement area 36 of the electrode section 35 of the piezoelectric vibration element 1, and most of it is disposed on the surface of the electrode section 35 and in each groove section 37 within the adhesive placement area 36. When the tip joint 38 is pressed against the mount section 120, the conductive adhesive 40 disposed in the adhesive placement area 36 is pushed outward from the adhesive placement area 36, ​​and some of it flows into each groove section 37 as shown in FIG.

[0030] As shown in FIG. 6, the content of the binder resin 41 and the conductive filler 42 in the conductive adhesive 40 is different between a pair of grooves 37 spaced apart in the Y direction and the center of the adhesive placement region 36 between these grooves 37. That is, the content of the conductive filler 42 is greater than the binder resin 41 in the grooves 37, and the content of the binder resin 41 is greater than the conductive filler 42 in the center between the grooves 37. The reason for this is that the binder resin 41, which has a low viscosity, is likely to enter the narrow gap between the opposing electrode pads 121 in the center by capillary action, and as a result, the content of the binder resin 41 is greater. Then, when a large amount of the binder resin 41 is collected in the center, the conductive filler 42 flows into the grooves 37 on both sides of the center as if being pushed out from the binder resin 41 in the center, and the content of the conductive filler 42 in the grooves 37 increases.

[0031] In the piezoelectric vibration element 1 of the embodiment, the tip joint 38 of the support part 30 is mechanically and firmly joined to the mount part 120 by the binder resin 41 present in a large amount in the center, which behaves as described above. Meanwhile, the electrode part 35 of the piezoelectric vibration element 1 and the electrode pad 121 of the mount part 120 are electrically connected to each other through the conductive filler 42 present in the groove parts 37 spaced apart in the Y direction. The groove parts 37 are distributed and arranged along the edge 36a of the adhesive arrangement area 36, ​​and are arranged on both sides (Y1 side and Y2 side) of the center part of the adhesive arrangement area 36 in the Y direction in which the support part 30 extends. Therefore, around the center part where the binder resin 41 is concentrated and firmly adhered to the mount part 120, the conductive filler 42 present in a large amount concentrated in the groove part 37 comes into contact with the electrode pad 121 of the mount part 120. Therefore, a large amount of conductive filler 42 present in groove 37 is accurately bonded to electrode pad 121 of mounting portion 120, and electrical connectivity by conductive filler 42 is stably ensured. Also, conductive filler 42 flowing from the center to the periphery enters groove 37 in large amounts and remains within groove 37, and the amount of conductive filler 42 flowing further to the periphery is reduced. Therefore, a large amount of conductive filler 42 is concentrated and arranged around the center, which also ensures stable electrical connectivity by conductive filler 42.

[0032] That is, in the manufacturing method of the piezoelectric vibrator 100 in this embodiment, in order to obtain the above-mentioned effect, when the electrode portion 35 of the support portion 30 in the piezoelectric vibration element 1 is joined via a conductive adhesive 40 that adheres to both the electrode portion 35 and the mounting portion 120, it is preferable that the conductive adhesive 40 that adheres to the electrode portion 35 side is arranged only in the adhesive arrangement area 36.

[0033] The adhesive placement region 36 in the embodiment is a region where the conductive adhesive 40 adheres to the electrode portion 35 when the electrode portion 35 of the piezoelectric vibration element 1 is brought into contact with the conductive adhesive 40. The adhesive placement region 36 may be preset in the electrode portion 35 of the piezoelectric vibration element 1, or may be a region that is generated during assembly depending on the viscosity, amount, etc. of the conductive adhesive 40. In any case, the adhesive placement region 36 in the embodiment does not include the entire groove portion 37, but is a region where the groove portion 37 crosses the edge 36a.

[0034] In the piezoelectric vibration element 1 of the embodiment, each of the multiple grooves 37 extends in two directions, the inner direction and the outer direction, of the edge 36a of the adhesive placement area 36. Therefore, by the conductive adhesive 40 flowing into these grooves 37, the bonding strength of the conductive adhesive 40 on both sides of the adhesive placement area 36 is improved, and the electrical connectivity of the conductive filler 42 in the center of the adhesive placement area 36 is stabilized.

[0035] In the piezoelectric vibration element 1 of the embodiment, a plurality of grooves 37 are arranged at two locations on either side of the center of the adhesive placement area 36. Each of the plurality of grooves 37 extends in two directions, that is, inward and outward directions of the edge 36a of the adhesive placement area 36, ​​and the two grooves 37 are arranged substantially parallel to each other at the locations where they are arranged. As a result, the bonding strength of the conductive adhesive 40 around the adhesive placement area 36 is improved, and the electrical connectivity of the conductive filler 42 at the center of the adhesive placement area 36 is stabilized. Note that, in the embodiment, two grooves 37 are formed at each of the locations, but three or more may be formed if possible.

[0036] The above is the piezoelectric vibration element 1 of the embodiment. The piezoelectric vibration element 1 has the following advantages:

[0037] (1) The piezoelectric vibration element 1 according to the embodiment is a piezoelectric vibration element housed in a package 110 and bonded to a mounting portion 120 in the package 110 via a conductive adhesive 40, and includes a support portion 30 bonded to the mounting portion 120 by the conductive adhesive 40, a vibration portion 20 that is continuous with the support portion 30 and has an excitation electrode formed thereon, and an electrode portion 35 provided on the surface of the support portion 30 facing the mounting portion 120, the electrode portion 35 having an adhesive placement area 36 in which the conductive adhesive 40 is placed, and a plurality of groove portions 37 distributed along the edge of the adhesive placement area 36, ​​and each of the plurality of groove portions 37 is arranged across the edge 36a of the adhesive placement area 36.

[0038] As a result, the piezoelectric vibration element 1 is bonded to the mount portion 120 of the package 110 in a state in which both mechanical bonding strength and stable electrical connection performance are achieved.

[0039] (2) In the piezoelectric vibration element 1 according to the embodiment, each of the grooves 37 extends in two directions, that is, inward and outward of the edge 36a of the adhesive application area 36.

[0040] This improves the bonding strength of the conductive adhesive 40 in the center of the adhesive application area 36 , and stabilizes the electrical connectivity of the conductive filler 42 around the periphery of the adhesive application area 36 .

[0041] (3) In the piezoelectric vibration element 1 according to the embodiment, the grooves 37 are disposed in at least two locations on either side of the center of the adhesive application region .

[0042] This improves the bonding strength of the conductive adhesive 40 in the center of the adhesive application area 36 , and stabilizes the electrical connectivity of the conductive filler 42 around the periphery of the adhesive application area 36 .

[0043] (4) In the piezoelectric vibration element 1 according to the embodiment, at the location where the groove portion 37 is arranged, at least two groove portions 37 arranged approximately parallel to each other are arranged.

[0044] This improves the bonding strength of the conductive adhesive 40 in the center of the adhesive application area 36 , and stabilizes the electrical connectivity of the conductive filler 42 around the periphery of the adhesive application area 36 .

[0045] (5) In the manufacturing method of the piezoelectric vibrator of the embodiment, when joining the electrode portion 35 of the support portion 30 in the piezoelectric vibration element 1 via conductive adhesive 40 adhering to both the electrode portion 35 and the mounting portion 120, it is preferable that the conductive adhesive 40 adhering to the electrode portion 35 side is arranged in the adhesive arrangement area 36.

[0046] This makes it easier to obtain a state in which the conductive filler 42 of the conductive adhesive 40 flows into the groove portion 37 and the binder resin 41 is disposed in the center of the adhesive disposing region 36. As a result, it is possible to manufacture a piezoelectric vibrator in which the piezoelectric vibration element 1 is bonded to the mounting portion 120 of the package 110 in a state in which both mechanical bonding strength and stable electrical connection performance are achieved.

[0047] Next, modified examples 1 to 3 of the piezoelectric vibration element in which the configuration of the groove portion 37 in the piezoelectric vibration element 1 of the above embodiment, such as the arrangement and number, are changed will be described. Note that in these modified examples 1 to 3, only the configuration of the groove portion 37 is changed, and other components are common to the above embodiment, so a description of the common components will be omitted and only the differences will be described. Note that Figures 7 to 9 showing modified examples 1 to 3 are all figures corresponding to Figure 3, and show the surface of the tip joint portion 38 of the support portion 30 facing the mount portion 120.

[0048] (Variation 1) The grooves 37 shown in Fig. 7 are disposed on either side of the center of the adhesive placement area 36, ​​one on the Y1 side and one on the Y2 side of the center. All of these grooves 37 extend in the Y direction and are disposed in the center of the support part 30 in the width direction. Each groove 37 crosses the edge 36a of the adhesive placement area 36 and extends in two directions, the inward direction and the outward direction of the edge 36a. According to this modification 1, the grooves 37 can be easily formed in the support part 30 having a small width, which is efficient in terms of productivity.

[0049] (Variation 2) 8 are disposed on either side of the center of the adhesive placement area 36, ​​with two grooves 37 on each of the Y1 and Y2 sides of the center. Each groove 37 extends at an angle with respect to the Y-axis direction so as to be oriented toward the center of the adhesive placement area 36, ​​and is generally disposed radially. According to this second modification, the conductive filler 42 that flows from the center of the adhesive placement area 36 to the periphery flows efficiently in large amounts into each groove 37, and the electrical connectivity by the conductive filler 42 around the center of the adhesive placement area 36 is stabilized.

[0050] (Variation 3) 9 are arranged in a grid pattern that intersects with each other around the center of the adhesive placement area 36. According to this third modification, the grooves 37 are present all around the center of the adhesive placement area 36, ​​so that electrical connectivity by the conductive filler 42 around the center of the adhesive placement area 36 is stable.

[0051] "Example" Next, an example in which a piezoelectric vibration element of the present invention was actually produced will be described. A piezoelectric vibration element having the same configuration as the above embodiment was produced, and the piezoelectric vibration element was bonded to a mounting part of a package with a conductive adhesive using Ag (silver) as a conductive filler. Then, the piezoelectric vibration element and the package were cut along a line corresponding to the XX line in FIG. 3, and the cross section was observed. FIG. 10A is a micrograph showing the state after the cross section was polished. FIG. 10B is a mapping image of Ag based on the micrograph of FIG. 10A.

[0052] The microscope photograph in Fig. 10A confirms that the two grooves formed on the surface of the support arm of the piezoelectric vibration element of the embodiment are filled with conductive adhesive. The conductive adhesive is also attached to one outer surface of the support arm (the left side surface in Fig. 10A). The mapping image in Fig. 10B confirms that the grooves are filled with conductive adhesive with a high Ag concentration, that the conductive adhesive that has penetrated into the narrow gap between the grooves has a low Ag concentration, and that the proportion of binder resin there is high.

[0053] The present invention is not limited to the above-described embodiment, and even if modifications and improvements are made within the scope of the present invention, they will still be included in the scope of the present invention.

[0054] For example, the multiple grooves formed in the tip joint 38 of the support 30 of the piezoelectric vibration element 1 may be disposed at any location as long as they are dispersed along the edge 36a of the adhesive application area 36. Furthermore, as long as the grooves cross the edge 36a of the adhesive application area 36, ​​their shape may be any shape and is not limited to a straight line like the grooves 37 in the above embodiment.

[0055] Although the piezoelectric vibration element 1 of the embodiment has a bilaterally symmetrical shape in plan view, the shape of the piezoelectric vibration element of the present invention is not limited to a bilaterally symmetrical shape. Therefore, the length, width, and spacing between the vibrating arms 21, 22 and the supporting arms 31, 32 are not limited. Furthermore, the supporting arms 31, 32 are not essential components, and the relay parts 15A, 15B and the constricted part 14 extending from the supporting arms 31, 32 to the base part 13 are not essential components, but are optional components.

[0056] There are no limitations on the type of piezoelectric vibration element, as long as it is supported by a support portion so that the vibration portion is free and has an electrode portion joined to the support portion by a conductive adhesive. [Explanation of symbols]

[0057] 1...piezoelectric vibration element, 10...substrate, 20...vibration portion, 30...support portion, 35...electrode portion, 36...adhesive placement area, 36a...edge of adhesive placement area, 37...groove portion, 40...conductive adhesive, 50...excitation electrode, 100...piezoelectric vibrator, 110...package, 120...mounting portion.

Claims

1. A piezoelectric vibration element that is housed in a package and bonded to a mount portion in the package via a conductive adhesive, a support portion joined to the mount portion by the conductive adhesive; a vibration section which is continuous with the support section and has an excitation electrode formed thereon; an electrode portion provided on a surface of the support portion facing the mount portion, The electrode portion has an adhesive placement area in which the conductive adhesive is placed; a plurality of grooves disposed along an edge of the adhesive placement area; A piezoelectric vibration element, wherein each of the plurality of grooves is arranged across an edge of the adhesive placement area.

2. The piezoelectric vibration element according to claim 1 , wherein the grooves are disposed at at least two locations on either side of a center of the adhesive application area.

3. The piezoelectric vibration element according to claim 2 , wherein each of the grooves extends in two directions, an inward direction and an outward direction of the edge of the adhesive placement area.

4. The piezoelectric vibration element according to claim 3 , wherein at least two of the grooves are arranged substantially parallel to each other at the location where the groove is arranged.

5. The piezoelectric vibration element according to claim 1 , wherein the plurality of grooves are arranged in a lattice pattern intersecting each other around a central portion of the adhesive application region.

6. 2. A method for manufacturing a piezoelectric vibrator, comprising the steps of: bonding the electrode portion of the support portion of the piezoelectric vibrating element according to claim 1 to a mounting portion via a conductive adhesive that adheres to both the electrode portion and the mounting portion, A method for manufacturing a piezoelectric vibrator, wherein the conductive adhesive attached to the electrode portion is placed in the adhesive placement area.

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