Piezoelectric vibrating reed and piezoelectric vibrator using the same

Abstract

To provide a piezoelectric vibration piece capable of suppressing occurrence of a failure caused by discharge between electrodes, and a piezoelectric vibrator using the same.SOLUTION: The crystal vibration piece 2 includes a crystal piece 6 having a pair of main surfaces 61, an excitation electrode 7 provided on the main surface 61, and an extraction electrode 8 extracted from the excitation electrode 7. The main surface 61 includes a first main-surface 61a portion and a second main-surface 61a portion facing the first main-surface 61b portion, the excitation electrodes 7 include a first excitation-electrode 61a portion provided on the first main-surface 7a portion and a second excitation-electrode 61b portion provided on the second main-surface 7b portion, and the lead-out electrodes 8 include a first lead-out electrodes 7a portion led out from the first excitation-electrode 8a portion and a second lead-out electrodes portion led out from the second excitation-electrode portion. 7b 8b. The crystal piece 6 includes a creepage distance expansion portion 62 that is a portion for expanding the creepage distance between the first excitation electrodes 7a and the second lead-out electrodes 8b and / or the creepage distance between the second excitation electrodes 7b and the first lead-out electrodes 8a.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present invention relates to a piezoelectric vibrating piece and a piezoelectric vibrator using the same. [Background technology]

[0002] Japanese Patent Application Laid-Open No. 2023-148198 discloses a quartz crystal vibrating piece that mainly includes a pair of excitation electrodes provided on each of the main surfaces of the quartz crystal piece and a pair of extraction electrodes drawn from each of the pair of excitation electrodes. For convenience in mounting the quartz crystal vibrating piece in a container, specifically to eliminate the difference between the front and back of the quartz crystal vibrating piece and to eliminate the need to align the front and back during mounting, the extraction electrode drawn from one of the excitation electrodes is located on the same main surface as the one excitation electrode and is also located on the opposite main surface (the main surface on which the other excitation electrode is located) via the side of the quartz crystal piece. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-148198 Summary of the Invention [Problem to be solved by the invention]

[0004] As quartz crystal resonator elements become smaller, the distance between one excitation electrode and an extraction electrode extending from the other excitation electrode to the same principal surface as the one excitation electrode inevitably becomes shorter. Accordingly, in small quartz crystal resonator elements, when a voltage is applied to the excitation electrode or extraction electrode due to insulation testing, static electricity, or the like, discharges are likely to occur between the excitation electrode and extraction electrode, which are the closest electrodes to each other. Such discharges are particularly likely to be a problem between an excitation electrode provided on one principal surface and an extraction electrode extending from the other principal surface to the one principal surface.

[0005] As quartz crystal resonator elements become smaller, the distance between one excitation electrode and the extraction electrode extending from the other excitation electrode to the same principal surface as the one excitation electrode inevitably becomes shorter. Therefore, when a voltage caused by an insulation test or static electricity is applied to the quartz crystal resonator, discharges are likely to occur, particularly between the excitation electrode provided on one principal surface and the extraction electrode extending from the other principal surface to the one principal surface. This discharge may damage a portion of the excitation electrode, which in turn causes problems such as fluctuations in the electrical characteristics of the quartz crystal resonator element.

[0006] An object of the present invention is to provide a piezoelectric vibrating piece that can suppress the occurrence of defects caused by discharge between electrodes, and a piezoelectric vibrator using the same. [Means for solving the problem]

[0007] The piezoelectric vibrating reed of the present invention includes a piezoelectric piece having a rectangular shape in a plan view and a pair of main surfaces, excitation electrodes provided on the main surfaces, and extraction electrodes extended from the excitation electrodes. The main surfaces include a first main surface and a second main surface opposite to the first main surface, the excitation electrodes include a first excitation electrode provided on the first main surface and a second excitation electrode provided on the second main surface, the extraction electrodes include a first extraction electrode extended from the first excitation electrode and a second extraction electrode extended from the second excitation electrode, and the piezoelectric piece includes a portion that extends the creepage distance between the first excitation electrode and the second extraction electrode and / or a creepage distance extension portion that extends the creepage distance between the second excitation electrode and the first extraction electrode.

[0008] In the above-described piezoelectric vibrating reed, the first extraction electrode may be formed on the first main surface, a side surface of the piezoelectric reed connected to the first main surface, and the second main surface, and / or the second extraction electrode may be formed on the second main surface, a side surface of the piezoelectric reed connected to the second main surface, and the first main surface. In this case, the first extraction electrode and / or the second extraction electrode may include a first extraction portion arranged on the same main surface as the excitation electrode from which the extraction originates, and a second extraction portion led from the first extraction portion and arranged on the main surface opposite the excitation electrode from which the extraction originates. Furthermore, the creepage distance extension portion may include one or more through holes provided between the excitation electrode and the second extraction portion, which are arranged on the same main surface, and penetrating in a direction intersecting the creepage distance direction between the excitation electrode and the second extraction portion.

[0009] Furthermore, in the above-mentioned piezoelectric vibrating piece, the first extraction electrode may be formed only on the first main surface and on a side surface of the piezoelectric piece connected to the first main surface, and not on the second main surface, and / or the second extraction electrode may be formed only on the second main surface and on a side surface of the piezoelectric piece connected to the second main surface, and not on the first main surface, and the creeping distance extension portion may be constituted by a portion of the second main surface where the first extraction electrode is not formed and / or a portion of the first main surface where the second extraction electrode is not formed.

[0010] The piezoelectric vibrator of the present invention includes the above-described piezoelectric vibrating piece and a container that is rectangular in plan view and that houses the piezoelectric vibrating piece, and the container has a long side dimension of 1.6 mm or less and a short side dimension of 1.2 mm or less. [Effects of the Invention]

[0011] The piezoelectric vibrating piece and the piezoelectric vibrator including the same of the present invention can increase the creepage distance between the excitation electrode provided on one main surface and the extraction electrode provided on the other main surface, even if the piezoelectric vibrating piece is small, thereby suppressing the occurrence of defects caused by discharge between the electrodes. [Brief explanation of the drawings]

[0012] [Figure 1A] 1 is a plan view of a quartz crystal resonator including a quartz crystal resonator element according to a first embodiment of the present invention. FIG. [Figure 1B] 1B is a cross-sectional view of the quartz crystal resonator taken along line IB-IB in FIG. 1A. [Figure 2] FIG. 2 is a plan view of the quartz crystal vibrating piece. [Figure 3] FIG. 10 is a plan view of a quartz crystal vibrating piece according to a first modified example of the first embodiment. [Figure 4] FIG. 10 is a plan view of a quartz crystal vibrating piece according to a second modified example of the first embodiment. [Figure 5] FIG. 10 is a plan view of a quartz crystal vibrating piece according to a third modified example of the first embodiment. [Figure 6] FIG. 10 is a plan view of a quartz crystal vibrating piece according to a fourth modified example of the first modified embodiment. [Figure 7A] FIG. 10 is a plan view of a quartz crystal vibrating piece according to a fifth modified example of the first embodiment. [Figure 7B] FIG. 7B is an enlarged view of part VIIB in FIG. 7A. [Figure 8] FIG. 13 is a plan view showing another modified example of the quartz crystal vibrating piece according to the fifth modified example. [Figure 9] FIG. 13 is a plan view showing another modified example of the quartz crystal vibrating piece according to the fifth modified example. [Figure 10A] FIG. 10 is a plan view of a quartz crystal resonator including a quartz crystal resonator piece according to a second embodiment. [Figure 10B] 10B is an end view of the crystal resonator taken along line XB-XB in FIG. 10A. [Figure 10C] 10D is an end view of the crystal resonator taken along line XC-XC in FIG. 10C. [Figure 11] 10 is a flowchart showing a bonding process. DETAILED DESCRIPTION OF THE INVENTION

[0013] <Piezoelectric vibrating element overview> An overview of the piezoelectric vibrating reed of the present invention will be described. The piezoelectric vibrating reed mainly comprises a piezoelectric piece, a pair of excitation electrodes, and a pair of extraction electrodes. The piezoelectric piece is formed in a rectangular shape when viewed from above. The piezoelectric piece has a pair of main surfaces, each of which is provided with an excitation electrode, and an extraction electrode is extracted from each excitation electrode. The piezoelectric piece has a creepage distance extension portion that extends the creepage distance between the excitation electrode provided on one main surface and the extraction electrode extracted from the excitation electrode provided on the other main surface, and / or the creepage distance between the excitation electrode provided on the other main surface and the extraction electrode extracted from the excitation electrode provided on the one main surface. As a result, the piezoelectric vibrating reed and a piezoelectric vibrator including the same can suppress defects in the piezoelectric vibrating reed caused by discharge between electrodes, even if the piezoelectric piece is small.

[0014] In other words, as the creepage distance decreases with the miniaturization of piezoelectric vibrators, electrostatic breakdown of the piezoelectric vibrating reed due to discharge between electrodes becomes more likely to occur. For example, the problem of electrostatic breakdown becoming more likely to occur becomes apparent in small piezoelectric vibrating reeds housed in a container that is approximately rectangular in plan view, with long sides of 1.6 mm or less and short sides of 1.2 mm or less. In contrast, the piezoelectric vibrating reed of the present invention extends the creepage distance to suppress discharge between electrodes and reduce electrostatic breakdown of the piezoelectric vibrating reed.

[0015] <1. First embodiment> <1-1. Structure of Crystal Unit 1> Hereinafter, each embodiment of the invention according to this application will be described with reference to the drawings. Note that each drawing used for the description is merely a schematic illustration to the extent that the invention can be understood. Furthermore, in each drawing used for the description, similar components are designated by the same numerals, and their description may be omitted. Furthermore, the shapes, materials, manufacturing methods, etc. described in the following embodiments are merely preferred examples within the scope of this invention. Therefore, the present invention is not limited to the following embodiments.

[0016] First, the configuration of a quartz crystal resonator 1, which is an example of a piezoelectric resonator according to a first embodiment, will be described with reference to Figures 1A and 1B. Figure 1A is a plan view of the quartz crystal resonator 1 including a quartz crystal vibrating piece 2 according to the first embodiment of the present invention, and Figure 1B is a cross-sectional view of the quartz crystal resonator 1 taken along line IB-IB in Figure 1A. Note that Figure 1A illustrates a state in which a lid 4, which will be described later, has been removed.

[0017] As shown in Figure 1, the quartz crystal vibrator 1 mainly comprises a quartz crystal vibrating piece 2 as a piezoelectric vibrating piece that vibrates in thickness shear mode, a container 3 that houses the quartz crystal vibrating piece 2, and a lid 4 that covers an opening 31a formed in the container 3.

[0018] The container 3 is a box-shaped member formed into a generally rectangular shape in a plan view. The container 3 mainly includes a concave storage section 31 having an opening on one side, a bank section 32 surrounding an opening 31a of the storage section 31, an adhesive pad 33 provided on a bottom surface 31b of the storage section 31, and an external connection terminal 34 provided on the outer bottom surface of the storage section 31.

[0019] The accommodation section 31 is formed to be able to accommodate the quartz crystal vibrating piece 2. The bank section 32 is a section that supports the lid 4 and is formed in a frame shape in a plan view. The adhesive pads 33 are members that fix and adhere the quartz crystal vibrating piece 2 to the bottom surface 31b of the accommodation section 31. The quartz crystal vibrating piece 2 is adhered to the adhesive pads 33 using a conductive adhesive 35 and is cantilevered on the adhesive pads 33 while floating above the bottom surface 31b. The external connection terminals 34 are terminals that electrically connect the quartz crystal vibrating piece 2 to an external electronic device (not shown). The adhesive pads 33 are electrically connected to the external connection terminals 34, and the quartz crystal vibrating piece 2 is electrically connected to the external electronic device via the conductive adhesive 35, the adhesive pads 33, and the external connection terminals 34.

[0020] <1-2. Schematic configuration of the quartz crystal resonator element 2> Next, a schematic configuration of the quartz crystal vibrating piece 2 will be described with reference to Figures 1A to 2. Figure 2 is a partially enlarged plan view of a portion of the quartz crystal vibrating piece 2.

[0021] As shown in FIGS. 1A and 1B, the quartz crystal vibrating piece 2 includes a quartz crystal blank 6, a pair of excitation electrodes 7, and a pair of extraction electrodes 8. The quartz crystal blank 6 is a piezoelectric piece made of quartz crystal and has a generally rectangular shape in a plan view. The quartz crystal blank 6 is an AT-cut quartz crystal blank, with its Y' plane (XZ plane) rotated approximately 35 degrees in the -Y-axis direction around the quartz crystal's X-axis as the rotation center, resulting in a Y' plane as its principal surface 61. Hereinafter, the axial direction of the AT-cut quartz crystal blank will be used as the reference, and the new tilted axes will be used as the Y'-axis and Z'-axis. The direction of the long side of the quartz crystal blank 6 (left-right direction in FIG. 2) will be the X-direction, the direction of the short side of the quartz crystal blank 6 (up-down direction in FIG. 2) will be the Z'-direction, and the direction perpendicular to the X- and Z'-axis directions (perpendicular to the plane of the paper in FIG. 2) will be the Y'-direction.

[0022] The crystal blank 6 mainly comprises a pair of principal surfaces 61 on the front and back sides, and a creepage distance widening portion 62. The principal surfaces 61 are formed as flat surfaces and include a first principal surface 61a and a second principal surface 61b opposite the first principal surface 61a. An excitation electrode 7 and an extraction electrode 8 are provided on each principal surface 61. The creepage distance widening portion 62 is a portion provided between the excitation electrode 7 and the extraction electrode 8 when the crystal blank 6 is viewed from the Y' direction (when the crystal blank 6 is viewed from above). The creepage distance widening portion 62 comprises two through holes 63 formed to penetrate along the Y' direction, and a dividing portion 64 located between the two through holes 63. Specifically, the dividing portion 64 is located between the two through holes 63 aligned in the Z' direction when the crystal blank 6 is viewed from the Y' direction.

[0023] The excitation electrodes 7 are electrodes that are rectangular in plan view and are provided on the principal surfaces 61, and one excitation electrode 7 is provided for each principal surface 61. Specifically, the excitation electrodes 7 include a first excitation electrode 7a provided on the first principal surface 61a and a second excitation electrode 7b provided on the second principal surface 61b, and each excitation electrode 7 is disposed in a central portion of each principal surface 61 at a position offset in the −X direction (right side in FIG. 2) (see FIG. 1A).

[0024] The extraction electrodes 8 are electrodes extracted from the excitation electrodes 7, and one extraction electrode 8 is extracted from one excitation electrode 7. Specifically, the extraction electrodes 8 include a first extraction electrode 8a extracted from the first excitation electrode 7a and a second extraction electrode 8b extracted from the second excitation electrode 7b. Each extraction electrode 8 also includes a first extraction portion 81 arranged on the same main surface 61 as the excitation electrode 7 from which it originates, and a second extraction portion 82 extracted from the first extraction portion 81 and arranged on the main surface 61 opposite to the excitation electrode 7 from which it originates.

[0025] Specifically, in this embodiment, the quartz-crystal vibrating piece 2 is disposed with the first principal surface 61a facing the bottom surface 31b of the housing 31 and the second principal surface 61b facing the opening 31a of the housing 31. A first lead portion 81 of the first lead electrode 8a led from the first excitation electrode 7a is provided on the first principal surface 61a, and a second lead portion 82 of the first lead electrode 8a led from the first lead portion 81 is provided on the second principal surface 61b. Below, the relationship between the first lead portion 81 of the second excitation electrode 7b and the second lead electrode 8b provided on the second principal surface 61b and the second lead portion 82 of the first lead electrode 8a will be described with reference to the drawings. However, the same relationship also applies to the relationship between the first lead portion 81 of the first excitation electrode 7a and the first lead electrode 7a provided on the first principal surface 61a and the second lead portion 82 of the second lead electrode 8b.

[0026] As shown in FIG. 2, on the second principal surface 61b, the first lead portion 81 is biased toward the +X direction (left side in FIG. 2) and the -Z' direction (lower side in FIG. 2) of the principal surface 61. Specifically, the first lead portion 81 is extended from the excitation electrode 7 to the edge of the principal surface 61 on the -Z' side, and is extended along the long side of the -Z' side of the principal surface 61 to the edge of the +X side of the principal surface 61. Furthermore, the first lead portion 81 is extended in the +Z' direction (upper side in FIG. 2) along the short side of the +X side of the principal surface 61. Note that FIGS. 1A and 2 illustrate the crystal blank 6 as viewed from the +Y' direction (the second principal surface 61b in plan view), and a portion of the first lead portion 81 of the first lead electrode 8a provided on the first principal surface 61a is illustrated by a dashed line.

[0027] The second lead portion 82 is biased toward the +X direction and the +Z' direction (upper side in FIG. 2) on the second principal surface 61b. Specifically, the second lead portion 82 on the second principal surface 61b is led from the first lead portion 81 of the first lead electrode 8a on the first principal surface 61a to the second principal surface 61b via the side surface of the crystal blank 6, and is then led in the -Z' direction along the short side on the +X' side of the second principal surface 61b.

[0028] <1-3. Detailed configuration of the creepage distance extension section 62> Next, we will explain the detailed configuration of the creepage distance widening portion 62. The creepage distance widening portion 62 is a portion provided to widen the creepage distance between the first excitation electrode 7a provided on the first main surface 61a and the second extraction portion 82 of the second extraction electrode 7b, or the creepage distance between the second excitation electrode 7b provided on the second main surface 61b and the second extraction portion 82 of the first extraction electrode 7a.

[0029] 2, with regard to the shape of the through holes 63 as viewed from the Y' direction, the through holes 63 are formed in a generally rectangular shape in plan view with the longer sides extending in the Z' direction. By providing the through holes 63 between the excitation electrodes 7 and the second lead portion 82 on each of the main surfaces 61, two through holes 63 are formed in the crystal blank 6. Note that in this embodiment, the through holes 63 are formed so that their longitudinal direction is aligned with the Y' direction, but it is sufficient that the longitudinal direction of the through holes 63 is formed so that it intersects the creepage distance direction between the excitation electrodes 7 and the second lead portion 82 (i.e., intersects the X direction and the Z' direction).

[0030] Here, the through hole 63 is provided between the excitation electrode 7 and the second lead portion 82, which are arranged on the same main surface 61. Specifically, if the region of the main surface 61 sandwiched between the excitation electrode 7 and the second lead portion 82 in the X direction (the region surrounded by the two-dot chain line in FIG. 2) is defined as a first region S1, the through hole 63 is provided so as to cross the first region S1 in the Z' direction.

[0031] That is, a first virtual line L1 connecting the +X side short side of the excitation electrode 7 and the -X side long side of the second lead portion 82, which are opposed to each other in the X direction, over the shortest distance (straight-line distance) passes through the first region S1. In contrast, the through hole 63 is disposed so as to cross the first region S1. Therefore, the shape of the second virtual line L2 connecting the excitation electrode 7 and the second lead portion 82 at a creeping distance includes a shape that follows the outline of the through hole 63. As a result, the second virtual line L2 is longer than the linear first virtual line L1.

[0032] In this way, the crystal vibrating piece 2 can prevent discharges from occurring between the excitation electrode 7 and the second lead portion 82, which are arranged on the same principal surface 61, by making the creepage distance between both the excitation electrode 7 and the through hole 63 (i.e., the length of the second imaginary line L2) greater than the linear distance between them (i.e., the length of the first imaginary line L1). Therefore, the crystal vibrating piece 2 can prevent malfunctions caused by discharges between the electrodes.

[0033] Furthermore, a portion of each through hole 63 is formed in a position that protrudes more inward (toward the first lead portion 81) than the second lead portion 82 in the Z' direction. Also, a portion of each through hole 63 is formed in a position that protrudes more outward (opposite the first lead portion 81) than the excitation electrode 7 in the Z' direction. In other words, the through hole 63 extends beyond the first region S1 in the Z' direction. This allows the quartz-crystal vibrating piece 2 to ensure a large creepage distance from the excitation electrode 7 to the second lead portion 82 (i.e., the length of the second imaginary line L2).

[0034] That is, the second imaginary line L2 passes through one of the short sides of the through hole 63. Therefore, the further the short side on the -Z' side of the through hole 63 is from the second lead portion 82, the longer the creepage distance. Similarly, the further the short side on the +Z' side of the through hole 63 is from the excitation electrode 7, the longer the creepage distance. In this way, since the through hole 63 of the quartz-crystal vibrating piece 2 protrudes in the Z' direction from the first region S1, discharge between the excitation electrode 7 and the second lead portion 82 can be effectively suppressed.

[0035] Furthermore, with respect to the position of the through hole 63, the linear distance D1 in the X direction between the second lead portion 82 and the through hole 63 is smaller than the dimension W1 of the through hole 63 in the X direction (the dimension of the short side of the through hole 63 as viewed from the Y' direction). Therefore, the quartz-crystal vibrating piece 2 can reduce the distance between the second lead portion 82 and the through hole 63 in the X direction.

[0036] That is, with respect to the second imaginary line L2 that starts at the excitation electrode 7 and extends to the second lead portion 82, the second imaginary line L2 moves along the +X direction from the excitation electrode 7 to the through hole 63, but moves in the +X direction and the +Z′ direction (diagonally upward and left in FIG. 2 ) from the through hole 63 to the second lead portion 82. In this case, if the position of the short side of the through hole 63 in the −Z′ direction is the same, the length of the second imaginary line L2 increases as the position of the through hole 63 in the X direction is closer to the +X side, i.e., the closer the distance between the through hole 63 and the second lead portion 82 in the X direction. In this way, by shortening the distance between the through hole 63 and the second lead portion 82 in the X direction, the crystal vibrating piece 2 can ensure a larger creepage distance between the excitation electrode 7 and the second lead portion 82.

[0037] Furthermore, since the crystal blank 6 includes the dividing portion 64, the decrease in strength of the creepage distance widening portion 62 due to the formation of the through hole 63 can be suppressed compared to when the creepage distance widening portion 62 is a single through hole 63 without the dividing portion 64. Therefore, the crystal vibrating blank 2 can maintain its drop resistance while widening the creepage distance from the excitation electrode 7 to the second lead portion 82.

[0038] Furthermore, the through hole 63 is formed so that the dimension W1 of the through hole 63 in the X direction (the dimension of the short side of the through hole 63 when viewed from the Y' direction) is smaller than the dimension W2 of the second lead portion 82 in the X direction (the dimension of the short side of the second lead portion 82). This allows the quartz crystal vibrating piece 2 to increase the creepage distance from the excitation electrode 7 to the second lead portion 82 while suppressing the effect of the through hole 63 on the characteristics of the quartz crystal contained in the quartz crystal piece 6.

[0039] As described above, the crystal vibrating piece 2 is provided with the creepage distance widening portion 62 between the excitation electrode 7 and the second lead portion 82 of the lead electrode 8. Therefore, compared to when the crystal vibrating piece 2 does not have the creepage distance widening portion 62, the crystal vibrating piece 2 has an extended creepage distance between the excitation electrode 7 and the second lead portion 82, which are arranged on the same main surface 61, making it possible to suppress the occurrence of discharge between them. As a result, the crystal vibrating piece 2 and the crystal resonator 1 using it can suppress the occurrence of defects caused by discharge between the electrodes.

[0040] <1-4-1. First Variation> Next, modifications of the first embodiment will be described with reference to Figures 3 to 9. First, a first modification of the first embodiment will be described with reference to Figure 3. While two through holes 63 are provided in the quartz crystal vibrating piece 2 in the first embodiment, only one through hole 163 is provided in the quartz crystal vibrating piece 102 in the first modification. Figure 3 is a partially enlarged plan view of the quartz crystal vibrating piece 102 in the first modification of the first embodiment.

[0041] As shown in FIG. 3 , the quartz crystal vibrating piece 102 of the first modification includes a quartz crystal blank 106, an excitation electrode 7, and an extraction electrode 8. The quartz crystal blank 106 includes a principal surface 61 and a creepage distance widening portion 162, and the creepage distance widening portion 162 includes one through-hole 163. The through-hole 163 is formed to cross both the first region S1 on one principal surface 61 and the first region S1 on the other principal surface 61 in the Z′ direction. The through-hole 163 is also formed to extend beyond the first region S1 on each principal surface 61 toward the +Z′ and −Z′ sides. This allows the quartz crystal vibrating piece 102 to ensure a larger creepage distance between the excitation electrode 7 and the second extraction portion 82. As a result, the quartz crystal vibrating piece 102 can suppress discharge between the excitation electrode 7 and the second extraction portion 82, which are arranged on the same principal surface 61, thereby reducing the occurrence of defects in the quartz crystal vibrating piece 102 caused by discharge between the electrodes.

[0042] <1-4-2. Second modified example> Next, a second modified example of the first embodiment will be described with reference to Fig. 4. While the quartz crystal vibrating piece 2 in the first embodiment has two through holes 63, the quartz crystal vibrating piece 202 in the second modified example has three through holes 263. Fig. 4 is a partially enlarged plan view of the quartz crystal vibrating piece 202 in the second modified example of the first embodiment.

[0043] 4, the quartz crystal vibrating piece 202 in the second modified example includes a quartz crystal piece 206, an excitation electrode 7, and an extraction electrode 8. The quartz crystal vibrating piece 202 includes a main surface 61 and a creepage distance widening portion 262, and the creepage distance widening portion 262 includes two first holes 263, a dividing portion 64, and one second hole 265. Note that the first hole 263 in this modified example has the same configuration as the two through holes 63 in the first embodiment.

[0044] The second holes 265 are through-holes with a substantially rectangular shape when viewed from the Y' direction, with the longer sides extending in the Z' direction. In the X direction, the second holes 265 are formed at positions overlapping the dividing portions 64 and at positions overlapping at least a portion of each of the first holes 263 (i.e., positions overlapping the second lead portion 82 and the first region S1). In this case, the second imaginary line L22 connecting the excitation electrode 7 and the second lead portion 82 at a creeping distance includes a meandering shape following the shapes of the first hole 263 and the second hole 265. Therefore, the quartz-crystal vibrating piece 202 can ensure a larger creeping distance between the excitation electrode 7 and the second lead portion 82. Therefore, the quartz-crystal vibrating piece 206 can suppress discharge between the excitation electrode 7 and the second lead portion 82, which are arranged on the same principal surface 61, thereby suppressing defects in the quartz-crystal vibrating piece 2 caused by discharge between the electrodes. Furthermore, compared to the crystal blank 106 of the first modification, the crystal blank 206 can suppress the decrease in strength that occurs with the formation of the creepage distance widening portion 262, and therefore the drop resistance of the crystal blank 206 can be maintained.

[0045] <1-4-3.Third modified example> Next, a third modified example of the first embodiment will be described with reference to Fig. 5. In the quartz crystal vibrating piece 2 of the first embodiment, the through-holes 63 are formed in a generally rectangular shape in plan view, whereas in the quartz crystal vibrating piece 302 of the third modified example, the through-holes 363 are formed in a generally L-shape in plan view. Fig. 5 is a partially enlarged plan view of the quartz crystal vibrating piece 302 of the third modified example of the first embodiment.

[0046] As shown in FIG. 5, the quartz crystal vibrating piece 302 of the third modified example includes a quartz crystal piece 306, an excitation electrode 7, and an extraction electrode 8. The quartz crystal piece 306 includes a principal surface 61 and a creepage distance widening portion 362. The creepage distance widening portion 362 includes two through holes 363 and a dividing portion 364. When viewed from the +Y′ direction, the through hole 363 is formed in a generally L-shape in plan view, surrounding the vertices located on the −X and −Z′ sides of the second extraction portion 82. Specifically, when viewed from the X direction, the through hole 363 is formed to extend beyond the first region S1 in the +Z direction (upper side in FIG. 5) and the −Z′ direction (lower side in FIG. 5), and also extends further in the +X direction (leftward in FIG. 5) from the portion of the through hole 363 that extends in the −Z′ direction. In other words, if the region of the crystal piece 6 located between the first lead portion 81 and the second lead portion 82 in the Z' direction (the vertical direction in Figure 5) (the region surrounded by a dotted line in Figure 5) is defined as the second region S2, the through hole 363 is formed at a position that includes at least a portion of the second region S2.

[0047] Here, the second imaginary line L32 connecting the excitation electrode 7 and the second lead portion 82 with a creepage distance includes a shape that follows the shape of the through hole 363, so the shape of the second imaginary line L32 extends in the +X direction by the same amount as the through hole 363 extends in the +X direction. This allows the quartz-crystal vibrating piece 302 to ensure a larger creepage distance between the excitation electrode 7 and the second lead portion 82. Therefore, the quartz-crystal vibrating piece 302 can suppress discharge between the excitation electrode 7 and the second lead portion 82, which are arranged on the same principal surface 61, and therefore suppress the occurrence of defects in the quartz-crystal vibrating piece 302 caused by discharge between the electrodes.

[0048] <1-4-4. Fourth modified example> Next, a fourth modification of the first embodiment will be described with reference to Fig. 6. Compared to the quartz-crystal vibrating piece 2 of the first embodiment, the quartz-crystal vibrating piece 402 of the fourth embodiment has a larger linear distance in the X direction between the second lead portion 82 and the through-hole 462. Fig. 6 is a partially enlarged plan view of the quartz-crystal vibrating piece 402 of the fourth modification of the first embodiment.

[0049] 6, the quartz crystal vibrating piece 402 in the fourth modified example includes a quartz crystal piece 406, an excitation electrode 7, and an extraction electrode 8. The quartz crystal piece 406 includes a main surface 61 and a creepage distance widening portion 462, and the creepage distance widening portion 462 includes two through holes 463 and a dividing portion 464. The two through holes 463 and the dividing portion 464 have the same configuration as the through hole 63 in the first embodiment, except for their positions in the X direction.

[0050] In the quartz-crystal vibrating piece 402, the linear distance D2 between the second lead portion 82 and the through hole 463 in the X direction is greater than the dimension W1 of the through hole 463 in the X direction (the dimension of the short side of the through hole 463 as viewed in the Y' direction). In this way, by increasing the distance between the second lead portion 82 and the through hole 463 in the X direction, the width of the quartz-crystal vibrating piece 402 from the short side of the quartz-crystal piece 406 in the -X direction to the through hole 463 can be reduced. Therefore, the load applied to the periphery of the through hole 463 in the quartz-crystal vibrating piece 402 is reduced, thereby preventing a decrease in strength of the quartz-crystal piece 6 due to the formation of the through hole 463. Note that in this modification, the number of through holes 463 may be one, like the through hole 163 in the quartz-crystal vibrating piece 106 in the first modification (see FIG. 3).

[0051] <1-4-5. Fifth Modification> Next, a fifth modified example of the first embodiment will be described with reference to Figures 7A and 7B. While the creepage distance widening portion 262 in the second modified example has one second hole 265, the creepage distance widening portion 562 in the fifth modified example has multiple second holes 566. Figure 7 is a partially enlarged plan view of a quartz crystal vibrating piece 502 in the fifth modified example of the first embodiment.

[0052] 7A and 7B, the quartz crystal vibrating piece 502 of the fifth modified example includes a quartz crystal piece 506, an excitation electrode 7, and an extraction electrode 8. The quartz crystal piece 506 includes a principal surface 61 and a creepage distance widening portion 562. The creepage distance widening portion 562 is a portion provided on each of the principal surfaces 61 on both sides so as to cross the first region S1 in the Z′ direction, and includes two through-hole groups 563 and a dividing portion 564.

[0053] The through-hole group 563 includes a plurality of first holes 565 and a plurality of second holes 566. The first holes 565 are through-holes that are generally circular in plan view, and the plurality of first holes 565 are arranged along the Z' direction. The second holes 566 are through-holes that are generally circular in plan view and are formed at positions that are shifted in the -X direction with respect to the second drawn-out portion 82 from the first holes 565, and the plurality of second holes 566 are arranged along the Z' direction. That is, the through-hole group 563 has a plurality of first holes 565 and a plurality of second holes 566 arranged in a staggered pattern.

[0054] The dividing portion 564 includes a large dividing portion 567, a first small dividing portion 568, and a second small dividing portion 569. The large dividing portion 564 has the same configuration as the dividing portion 64 in the first embodiment, and is located between two through-hole groups 563 aligned in the Z' direction when the crystal blank 506 is viewed from the Y' direction. The first small dividing portion 568 is a portion located between adjacent first holes 565, and the multiple first holes 565 are aligned along the Z' direction with the first dividing portion 568 sandwiched between them. The second small dividing portion 569 is a portion located between adjacent second holes 566, and the multiple second holes 566 are aligned along the Z' direction with the second dividing portion 569 sandwiched between them.

[0055] Here, the second hole 566 is formed at a position overlapping the first dividing portion 568 in the X direction, and the first hole 565 is formed at a position overlapping the second dividing portion 569 in the X direction. As a result, the second imaginary line L52 connecting the excitation electrode 7 and the second lead portion 82 at a creepage distance includes a shape that follows at least the shape of the first hole 565, so that the quartz-crystal vibrating piece 502 can ensure a larger creepage distance between the excitation electrode 7 and the second lead portion 82. Therefore, the quartz-crystal vibrating piece 502 can suppress discharge between the excitation electrode 7 and the second lead portion 82, which are arranged on the same principal surface 61, and therefore suppress the occurrence of defects in the quartz-crystal vibrating piece 502 caused by discharge between the electrodes.

[0056] Although the present embodiment has been described with reference to an example in which the first holes 565 and the second holes 566 have the same shape when the crystal blank 6 is viewed in a plan view, they may have different shapes. Furthermore, the present embodiment has been described with reference to an example in which the multiple first holes 565 all have the same shape when the crystal blank 6 is viewed in a plan view, but they may have different shapes, and the same applies to the second holes 566. Furthermore, the present embodiment has been described with reference to an example in which the spacing between the multiple first holes 565 and the spacing between the multiple second holes 566 arranged in the Z′ direction are the same, but they do not have to be the same. Furthermore, the present embodiment has been described with reference to an example in which the spacing between the multiple first holes 565 is constant when the crystal blank 6 is viewed in a plan view, but it does not have to be constant, and the same applies to the second holes 566.

[0057] Furthermore, in the present embodiment, the case where two through-hole groups 563 are separated by the major dividing portion 567 has been described as an example, but the present invention is not limited to this, and the major dividing portion 567 may be omitted. That is, the dividing portion may include a first small dividing portion 568 and a second small dividing portion 569, and in the present embodiment, a first hole 565 and a second hole 566 may also be formed in the portion where the major dividing portion 567 is formed, and the creepage distance expansion portion may include one through-hole group.

[0058] Next, another variation of the fifth variation, which combines the third or fourth variation, will be described with reference to Figures 8 and 9. Figures 8 and 9 are partially enlarged plan views of quartz crystal vibrating pieces 602 and 702, respectively, which are variations of the fifth variation. Figure 8 shows quartz crystal vibrating piece 602, which is a variation of the fifth variation, combining the third variation with the fifth variation, and Figure 9 shows quartz crystal vibrating piece 702, which is a variation of the fifth variation, combining the fourth variation with the fifth variation.

[0059] 8, the quartz-crystal vibrating piece 602 has two through-hole groups 663 arranged side by side in the Z′ direction with a large dividing portion 667 sandwiched between them. The through-hole groups 663 are composed of a plurality of first holes 665 and a plurality of second holes 666 arranged in a generally L-shape in plan view, following the shape of the second lead-out portion 82. That is, in the quartz-crystal vibrating piece 602, the first holes 665 and the second holes 666 are formed not only in the first region S1 but also in the second region S2.

[0060] Specifically, in the second region S2 of the second main surface 61b, the first holes 665 include a plurality of through holes aligned in the X direction with a first dividing portion 668 sandwiched between them, and the second holes 666 include a plurality of through holes aligned in the X direction with a second dividing portion 669 sandwiched between them. Of the second holes 666, the through holes arranged in the second region S2 are located farther away from the second lead portion 82 in the -Z′ direction than the first holes 665 and are formed at positions overlapping with the first dividing portion 668 in the Z′ direction. That is, in the through hole group 663, the plurality of first holes 665 and the plurality of second holes 666 are arranged in a staggered pattern along the Z′ direction in the first region S1, and are arranged in a staggered pattern along the X direction in the second region S2. The plurality of first holes 665 and the plurality of second holes 666 are arranged such that an imaginary line connecting the excitation electrode 7 and the second lead portion 82 at a creeping distance includes a shape that follows at least the shape of the first hole 665 or the second hole 666.

[0061] This allows the quartz-crystal vibrating piece 602 to ensure a larger creepage distance between the excitation electrode 7 and the second lead portion 82. Therefore, the quartz-crystal vibrating piece 602 can suppress discharge between the excitation electrode 7 and the second lead portion 82, which are arranged on the same main surface 61, and therefore suppress the occurrence of defects in the quartz-crystal vibrating piece 602 caused by discharge between the electrodes.

[0062] 9, in the quartz-crystal vibrating piece 702, a linear distance D3 in the X direction between the second lead portion 82 and the through-hole group 763 (first hole 765) is greater than a diameter W2 of each through-hole constituting the through-hole group 763. The through-hole group 763 is formed in a generally C-shape in plan view, surrounding the short side of the excitation electrode 7 in the -X direction.

[0063] Specifically, the first holes 765 are through holes arranged in a C-shape with a first divided portion 768 sandwiched between them when viewed from the Y′ direction, and the second holes 766 are through holes arranged in a C-shape with a second small divided portion 769 sandwiched between them when viewed from the Y′ direction, and are formed at a position closer to the excitation electrode 7 than the first holes 765. That is, in the through hole group 763, the first holes 765 and the second holes 766 arranged in a C-shape are arranged in a staggered pattern. The first holes 765 and the second holes 766 are arranged so that an imaginary line connecting the excitation electrode 7 and the second lead portion 82 at a creeping distance includes a shape that follows at least the shape of the first hole 765 or the second hole 766.

[0064] This allows the quartz-crystal vibrating piece 702 to ensure a larger creepage distance between the excitation electrode 7 and the second lead portion 82. Therefore, the quartz-crystal vibrating piece 702 can suppress discharge between the excitation electrode 7 and the second lead portion 82, which are arranged on the same principal surface 61, thereby suppressing malfunctions of the quartz-crystal vibrating piece 702 caused by discharge between the electrodes. Furthermore, because the width dimension from the short side of the quartz-crystal vibrating piece 702 in the -X direction to the through-hole group 763 can be reduced, the quartz-crystal vibrating piece 702 can suppress a decrease in strength of the quartz-crystal vibrating piece 706 that occurs when the through-hole group 763 is formed.

[0065] 2. Second Embodiment <2-1. Structure of the crystal vibrating piece 1002> Next, a quartz crystal vibrating piece 1002, which is an example of a piezoelectric vibrator according to the second embodiment, will be described with reference to FIGS. 10A to 10C. FIG. 10A is a plan view of a quartz crystal vibrating piece 1001 including the quartz crystal vibrating piece 1002 according to the second embodiment. FIG. 10B is an end view of the quartz crystal vibrating piece 1001 taken along line XB-XB in FIG. 10A. FIG. 10C is an end view of the quartz crystal vibrating piece 1001 taken along line XC-XC in FIG. 10A. Note that in FIGS. 10B and 10C, the shape of the applied conductive adhesive 35 is schematically illustrated to clearly explain the positional relationship between the conductive adhesive 35 and the excitation electrodes 7.

[0066] As shown in Figures 10A to 10C, the quartz crystal vibrator 1001 mainly comprises a quartz crystal vibrating piece 1002, a container 3, and a lid 4, and the quartz crystal vibrating piece 1002 comprises a quartz crystal piece 1006, a pair of excitation electrodes 7, and a pair of extraction electrodes 1008.

[0067] The quartz crystal blank 1006 is an AT-cut quartz crystal blank made of quartz crystal and rectangular in plan view. The pair of principal surfaces 61 includes a first principal surface 61a and a second principal surface 61b facing the first principal surface 61a. Each principal surface 61 is provided with an excitation electrode 7 and an extraction electrode 1008. The extraction electrode 1008 includes a first extraction electrode 1008a extracted from the first excitation electrode 7a and a second extraction electrode 1008b extracted from the second excitation electrode 7b. In this embodiment, the quartz crystal vibrating blank 1002 is positioned with the first principal surface 61a facing the bottom surface 31b of the container 3 and the second principal surface 61b facing the opening 31a.

[0068] Here, the first extraction electrode 1008a is formed only on the first principal surface 61a and the side surface of the quartz-crystal vibrating piece 1002 that is connected to the first principal surface 61a, but is not formed on the second principal surface 61b. Similarly, the second extraction electrode 1008b is formed only on the second principal surface 61b and the side surface of the quartz-crystal vibrating piece 1002 that is connected to the second principal surface 61b, but is not formed on the first principal surface 61a. In other words, each extraction electrode 1008 does not have a configuration equivalent to the second extraction portion (see FIG. 2) that the extraction electrode 8 in the first embodiment had, and the extraction electrode 1008 is not arranged on the principal surface 61 of the quartz-crystal vibrating piece 1002 that is opposite the excitation electrode 7 from which it is extracted.

[0069] Then, on the second principal surface 61b directly behind the position on the first principal surface 61a where the first extraction electrode 1081a is arranged, there is formed a creepage distance widening portion 1063 configured by a portion where the first extraction electrode 1008a is not formed (a portion where neither the excitation electrode 7 nor the extraction electrode 1008 is arranged). Similarly, on the first principal surface 61a directly behind the position on the second principal surface 61b where the second extraction electrode 1081b is arranged, there is formed a creepage distance widening portion 1063 configured by a portion where the second extraction electrode 1008b is not formed.

[0070] In this way, the quartz crystal vibrating piece 1002 is provided with the creepage distance extension portion 1063, which allows for an extension of the creepage distance between one excitation electrode 7 and the extraction electrode 1008 extracted from the other excitation electrode 7. Therefore, the quartz crystal vibrating piece 1002 can suppress the occurrence of defects caused by discharge between the electrodes.

[0071] 11, a description will be given of the bonding process for fixing the crystal vibrating piece 1002 to the bonding pad 33 with the conductive adhesive 35. FIG. 11 is a flowchart showing the bonding process.

[0072] 11, the bonding process begins by applying a conductive adhesive 35 to one of the two bonding pads 33 mounted on the bottom surface 31b of the container 3 (first adhesive application process S1). Specifically, the first adhesive application process S1 is a process of applying the conductive adhesive 35 to the bonding pad 33 to which the extraction electrode 1008 (first extraction electrode 1008a in this embodiment) provided on the main surface 61 (first main surface 61a in this embodiment) of the quartz crystal vibrating piece 1002 facing the bottom surface 31b is bonded.

[0073] Next, in the bonding process, the conductive adhesive 35 is applied to one of the bonding pads 33 in the first adhesive application process S1, and then the quartz-crystal vibrating piece 1002 is placed (the vibrating piece placement process S2). Specifically, in the vibrating piece placement process S2, one of the main surfaces 61 (the first main surface 61a in this embodiment) is positioned facing the bottom surface 31b, and the conductive adhesive 35 applied to one of the bonding pads 33 is bonded to one of the extraction electrodes 8 (the first extraction electrode 8a). In the first adhesive application process S1, it is preferable to adjust the amount of conductive adhesive 35 applied so that the conductive adhesive 35 is in reliable contact with the first main surface 61a while preventing the conductive adhesive 35 from adhering to the second main surface 61b. This prevents the conductive adhesive 35 from adhering to the creepage distance extension portion 1063 formed on the second main surface 61b, thereby suppressing discharge between the electrode provided on the second main surface 61b and the conductive adhesive 35.

[0074] Next, in the bonding step, with one extraction electrode 8 adhered to the bonding pad 33, a conductive adhesive 35 is applied to the other extraction electrode 8, and the other extraction electrode 8 is bonded to the other bonding pad 33 (second adhesive application step S3). Specifically, in the second adhesive application step S3, with the quartz-crystal vibrating piece 1002 fixed to the bottom surface 3 with the other main surface 61 (second main surface 61b in this embodiment) facing the opening 31a, the conductive adhesive 35 is applied to the other extraction electrode 1008 (second extraction electrode 1008b in this embodiment) provided on the other main surface 61 from the opening 31a side, and the other extraction electrode 1008 is bonded to the other bonding pad 33.

[0075] The amount of conductive adhesive 35 applied in this second adhesive application step S3 is sufficient as long as the other extraction electrode 1008 and the other bonding pad 33 are electrically connected via the conductive adhesive 35. In this regard, it is preferable to use less conductive adhesive 35 for the second extraction electrode 1008b than for the first extraction electrode 1008a. This makes it possible to prevent the conductive adhesive 35 applied to the second extraction electrode 1008b from adhering to the creepage distance extension portion 1063 formed on one main surface 61. This makes it possible to prevent discharge from occurring between the conductive adhesive 35 and the electrode provided on one main surface 61.

[0076] Furthermore, in the bonding process, since the conductive adhesive 35 is applied to the second extraction electrode 1008b from the opening 31a side in the second adhesive application process S3 while the quartz vibrating piece 1002 is fixed to the container 3 in the vibrating piece placement process S2, the flow of the applied conductive adhesive 35 can be easily controlled. That is, as described above, in the second adhesive application process S3, it is preferable to prevent the conductive adhesive 35 from adhering to the creepage distance extension portion 1063 formed on the first main surface 61a. However, when the conductive adhesive 35 is applied to the bonding pad 33, and the quartz vibrating piece 1002 is then placed and bonded to the bonding pad 33, the conductive adhesive 35 is compressed and spreads, and it is difficult to control how the conductive adhesive 35 spreads. In contrast, when the conductive adhesive 35 is applied to the second extraction electrode 1008b from the opening 31a side, the conductive adhesive 35 is not compressed between the quartz crystal vibrating piece 1002 and the bonding pad 33, making it easier to control the flow of the conductive adhesive 35 so that it does not adhere to the first main surface 61a. Therefore, the quartz crystal vibrating piece 1002 can reduce the occurrence of defects caused by discharge between the conductive adhesive 35 and the electrode.

[0077] In this way, the quartz crystal unit 1001 manufactured through the bonding process can ensure a creepage distance between the conductive adhesive 35 applied to the second extraction electrode 1008b and the excitation electrode 7 provided on one main surface 61. Therefore, the quartz crystal unit 1001 can suppress discharge occurring between the conductive adhesive 35 and the excitation electrode 7, thereby reducing the occurrence of defects caused by discharge.

[0078] On the other hand, by using a larger amount of conductive adhesive 35 for the first extraction electrode 1008a than for the second extraction electrode 1000b, the quartz crystal vibrating piece 1002 can be securely fixed to the container 3.

[0079] This embodiment is intended for a small resonator, specifically a quartz crystal resonator having a container 3 with a long side dimension of 1.6 mm or less and a short side dimension of 1.2 mm or less, commonly referred to as a 1612 size or less. Therefore, it is intended for application to a quartz crystal resonator piece 1002 of a size that can be accommodated in this container 3, which is lightweight and small. Therefore, the amount of conductive adhesive 35 required to secure the quartz crystal resonator piece 1002 to the container 3 is considered to be small enough to provide sufficient adhesive strength compared to a quartz crystal resonator piece 1002 used in a container 3 larger than the above dimensions. In this regard, it is considered that the amount of conductive adhesive 35 applied to the first extraction electrode 1008a does not need to be larger than that for a quartz crystal resonator piece 1002 used in a container 3 larger than the above dimensions.

[0080] <3. Other variations> In the above embodiments, the piezoelectric piece is a quartz crystal piece 6, but the piezoelectric piece may be a piezoelectric material other than quartz. Also, in the present embodiment, the quartz crystal piece 6 is an AT-cut quartz crystal piece, but it may be other than an AT-cut (for example, an SC-cut).

[0081] In the above-described first embodiment, first modified example, second modified example, and fourth modified example, the through-holes 63, 163, 463, the first holes 263, and the second holes 265 have been described as being generally rectangular in plan view, but this is not limiting and they may have other shapes such as an ellipse. Similarly, in the fifth modified example, the first holes 565, 665, 765, and the second holes 665, 666, 766 have been described as being generally circular in plan view, but this is not limiting and they may have other shapes such as a rectangle. [Explanation of symbols]

[0082] 2,102,202,302,402,502,602,702,1002: quartz crystal vibrating piece (piezoelectric vibrating piece), 6,106,206,306,406,506,606,706,1006: quartz crystal piece (piezoelectric piece), 61: main surface, 61a: first main surface, 61b: second main surface, 62,162,262,362,462,562,1062: creepage distance extension portion, 63,163,363,463: through hole, 563,663,763: through hole group, 64,364,464,564: dividing portion, 263,565,665,765: first hole, 265,566,666,766: second hole, 567, 667: large dividing portion (dividing portion), 568, 668: first small dividing portion (dividing portion), 569, 669: second small dividing portion, 7: excitation electrode, 7a: first excitation electrode, 7b: second excitation electrode, 8, 1008: extraction electrode, 8a, 1008a: first extraction electrode, 8b, 1008b: second extraction electrode 81: first extraction portion, 82: second extraction portion, D1, D2: linear distance between the second extraction portion and the through hole (linear distance between the second extraction portion and the through hole in the long side direction of the piezoelectric piece), L1: first virtual line (an example of a linear distance), L2, L12, L22, L32, L42, L52: second virtual line (an example of a creepage distance), S1: first overlapping region, S2: second overlapping region, W1: Short side dimension of the through hole (dimension of the through hole in the long side direction of the piezoelectric strip), W2: Short side dimension of the second lead-out portion (dimension of the second lead-out portion in the long side direction of the piezoelectric strip)

Claims

1. A piezoelectric element having a rectangular shape in a plan view and a pair of main surfaces, and an excitation electrode provided on the main surfaces; a lead electrode led out from the excitation electrode, the main surface includes a first main surface and a second main surface opposite to the first main surface, the excitation electrodes include a first excitation electrode provided on the first principal surface and a second excitation electrode provided on the second principal surface, the extraction electrodes include a first extraction electrode extracted from the first excitation electrode and a second extraction electrode extracted from the second excitation electrode, The piezoelectric vibrating piece has a portion that expands the creepage distance between the first excitation electrode and the second extraction electrode, and / or a creepage distance expansion portion that expands the creepage distance between the second excitation electrode and the first extraction electrode.

2. the first extraction electrode is formed on the first main surface, a side surface of the piezoelectric piece connected to the first main surface, and the second main surface; and / or the second extraction electrode is formed on the second main surface, a side surface of the piezoelectric piece connected to the second main surface, and the first main surface; The first extractor electrode and / or the second extractor electrode are a first extraction portion disposed on the same principal surface as the excitation electrode from which the electrode is extracted; a second lead portion that is led out from the first lead portion and is disposed on the main surface opposite to the excitation electrode from which the lead is led out; Equipped with The creepage distance expansion portion is 2. The piezoelectric vibrating piece according to claim 1, further comprising one or more through holes formed between the excitation electrode and the second extraction portion, arranged on the same main surface, and extending in a direction intersecting the creepage distance direction between the excitation electrode and the second extraction portion.

3. The piezoelectric vibrating piece according to claim 2 , wherein a dimension of the through hole in a long side direction of the piezoelectric piece is smaller than a dimension of the second lead portion in the long side direction.

4. 3. The piezoelectric vibrating piece according to claim 2, wherein the creepage distance widening portion crosses a region located between the excitation electrode and the second lead portion in the short side direction when the main surface is viewed in plan.

5. The creepage distance expansion portion is A plurality of the through holes; a dividing portion located between the plurality of through holes; The piezoelectric vibrating reed according to claim 4 , comprising:

6. The plurality of through holes are a plurality of first holes which are the through holes arranged in the short side direction with the dividing portion interposed therebetween; a second hole which is the through hole formed at a position shifted in the long side direction with respect to the first hole and overlapping with the dividing portion when viewed from the long side direction; Including, The piezoelectric vibrating piece according to claim 5 , wherein the second holes are formed at positions overlapping at least a portion of each of the first holes when viewed from the long side direction.

7. The plurality of through holes are Two of the first holes; one of the second holes; The piezoelectric vibrating reed according to claim 6 , comprising:

8. the second holes are a plurality of the through holes arranged in the short side direction with the dividing portion interposed therebetween, The piezoelectric vibrating piece according to claim 6 , wherein the creepage distance widening portion includes a through-hole group in which the plurality of first holes and the plurality of second holes are arranged in a staggered pattern.

9. The piezoelectric vibrator according to claim 4 , wherein a portion of the through hole is formed at a position that protrudes further toward the first lead portion than the second lead portion.

10. The piezoelectric vibrating piece according to claim 9 , wherein the creepage distance expansion portion includes one of the through holes.

11. The piezoelectric vibrator according to claim 9 , wherein a portion of the through hole is formed between the first lead portion and the second lead portion in the short side direction when the main surface is viewed in plan.

12. The piezoelectric vibrating piece according to claim 2 , wherein a linear distance between the second lead portion and the through hole in the long side direction is smaller than a dimension of the through hole in the long side direction.

13. The piezoelectric vibrating piece according to claim 2 , wherein a linear distance between the second lead portion and the through hole in the long side direction is equal to or greater than a dimension of the through hole in the long side direction.

14. the first extraction electrode is formed only on the first main surface and a side surface of the piezoelectric piece connected to the first main surface, and is not formed on the second main surface; and / or the second extraction electrode is formed only on the second main surface and a side surface of the piezoelectric piece that is continuous with the second main surface, and is not formed on the first main surface; The piezoelectric vibrating piece according to claim 1 , wherein the creepage distance expansion portion is formed by a portion of the second main surface where the first extraction electrode is not formed and / or a portion of the first main surface where the second extraction electrode is not formed.

15. The piezoelectric vibrating piece according to any one of claims 1 to 14, A piezoelectric vibrator including a container having a rectangular shape in a plan view that accommodates the piezoelectric vibrating piece, The piezoelectric vibrator, wherein the container has a long side dimension of 1.6 mm or less and a short side dimension of 1.2 mm or less.

16. The piezoelectric vibrating piece according to claim 14, a container that accommodates the piezoelectric vibrating piece and is electrically connectable to an external electronic device; a conductive adhesive that adheres the piezoelectric vibrating piece to the container and electrically connects the first extracted electrode and the second extracted electrode to the container; A piezoelectric vibrator comprising: When the piezoelectric piece is disposed with the first main surface facing the bottom surface of the container, A piezoelectric vibrator, wherein the amount of the conductive adhesive used for the second extraction electrode is less than the amount of the conductive adhesive used for the first extraction electrode.

17. The piezoelectric vibrating piece according to claim 14, a container that accommodates the piezoelectric vibrating piece and is electrically connectable to an external electronic device; a conductive adhesive that adheres the piezoelectric vibrating piece to the container and electrically connects the first extracted electrode and the second extracted electrode to the container; A piezoelectric vibrator comprising: When the piezoelectric piece is disposed with the first main surface facing the bottom surface of the container, the conductive adhesive on the first extraction electrode side is provided only on a partial region on the first main surface of the first extraction electrode and on a side surface of the piezoelectric piece connected thereto, A piezoelectric vibrator in which the conductive adhesive on the second extracted electrode side is provided only on a partial area on the second main surface of the second extracted electrode and on a side surface of the piezoelectric piece connected thereto.

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