Vibrating element, vibrating device, and method for manufacturing a vibrating element

Abstract

To provide a vibration piece that has improved strength, a vibration device, and a method for manufacturing the vibration piece.SOLUTION: A vibration piece comprises: a vibration part 110 that has a first principal face 101, a second principal face 102, a first side face 103, and a second side face 104; a support part 120 that has a first support-side face 121 arranged separate from the vibration part 110 and arranged opposite to the first side face 103 of the vibration part 110, and a second support-side face 122 extending in a direction intersecting a direction in which the first support-side face 121 extends; and a connection part 130 that has a first connection face 131 connected with the first side face 103 and the first support-side face 121, and a second connection face 132 connected with the second side face 104 and the second support-side face 122. The first connection face 131 has a curved face in at least one of a first portion 131A connected with the first side face 103 and a second portion 131B connected with the first support-side face 121.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vibrating piece, a vibrating device, and a method for manufacturing a vibrating piece. [Background Art]

[0002] Patent Document 1 discloses a piezoelectric vibrating piece configured to include: a vibrating portion provided with a pair of excitation electrodes; a support portion extending apart from the vibrating portion; and a connecting portion extending to connect one end of the support portion to an end of the vibrating portion, wherein extraction electrodes are each drawn from the pair of excitation electrodes to a bonding surface of the support portion, whereby the influence of support stress on vibration is suppressed. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2015-186196 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] However, in the technology described in Patent Document 1, the connecting portion is provided biased to one side of the vibrating piece, and therefore, when an impact is applied from the outside, stress concentrates on the right-angled portion inside the connecting portion, which may cause the piezoelectric vibrating piece to crack or break. [Means for Solving the Problem]

[0005] The vibrating piece comprises a vibrating section having a first main surface, a second main surface facing the first main surface, a first side surface connecting the first main surface and the second main surface, and a second side surface extending in a direction intersecting the direction in which the first side surface extends; a support section having a first support side surface spaced apart from the vibrating section and facing the first side surface of the vibrating section, and a second support side surface extending in a direction intersecting the direction in which the first support side surface extends; and a connecting section having a first connecting surface connected to the first side surface and the first support surface, and a second connecting surface connected to the second side surface and the second support surface, wherein the first connecting surface has a curved surface on at least one of a first portion connected to the first side surface and a second portion connected to the first support surface.

[0006] The vibration device comprises the vibrating piece described above, a base on which the vibrating piece is mounted, and a container for housing the vibrating piece, wherein the support portion of the vibrating piece is joined to the base via a bonding material.

[0007] A method for manufacturing a vibrating piece includes preparing a substrate, forming a protective film on the substrate that constitutes an outer shape pattern, and using the protective film as a mask, etching the substrate to form a vibrating piece with an outer shape corresponding to the outer shape pattern, wherein the vibrating piece has a vibrating portion having a first main surface, a second main surface that is in a front-back relationship with the first main surface, a first side surface connecting the first main surface and the second main surface, and a second side surface extending in a direction intersecting the direction in which the first side surface extends, and the vibrating portion The support portion has a first support surface that is spaced apart from the first side surface of the vibrating portion and is positioned opposite to the first side surface of the vibrating portion, and a second support surface that extends in a direction intersecting the direction in which the first support surface extends, and a connecting portion has a first connecting surface connected to the first side surface and the first support surface, and a second connecting surface connected to the second side surface and the second support surface, wherein the first connecting surface has a curved surface on at least one of the first portion connected to the first side surface and the second portion connected to the first support surface. [Brief explanation of the drawing]

[0008] [Figure 1] A plan view showing the configuration of the vibration device. [Figure 2] A cross-sectional view of the vibration device shown in Figure 1, along line AA. [Figure 3] A plan view showing the configuration of the vibrating element. [Figure 4] A cross-sectional view of the vibrating piece along the BB line shown in Figure 3. [Figure 5] A flowchart illustrating the manufacturing method of a vibrating element. [Figure 6] A plan view showing the configuration of a modified vibrating element. [Figure 7] A plan view showing the configuration of a modified vibrating element. [Figure 8] A plan view showing the configuration of a modified vibrating element. [Figure 9] A plan view showing the configuration of a modified vibrating element. [Figure 10] A plan view showing the configuration of a modified vibrating element. [Modes for carrying out the invention]

[0009] In the following diagrams, the three mutually orthogonal axes are described as the X-axis, Y-axis, and Z-axis. The direction along the X-axis is referred to as the "X direction," the direction along the Y-axis as the "Y direction," and the direction along the Z-axis as the "Z direction." The direction of the arrow is the + direction, and the direction opposite to the + direction is the - direction. The +Z direction is also sometimes referred to as "up" or "upward," and the -Z direction as "down" or "downward." Viewing from the +Z and -Z directions is also called a planar view or planar perspective. Furthermore, the surface on the Z-direction + side is described as the top surface, and the surface on the opposite side of the Z-direction - side is described as the bottom surface.

[0010] First, the configuration of the vibration device 100 will be explained with reference to Figures 1 and 2. Note that, for the sake of clarity, the lid 47 is omitted from Figure 1.

[0011] As shown in Figures 1 and 2, the vibration device 100 comprises a vibration element 1, a container 40 made of ceramic or the like that houses the vibration element 1, and a lid 47 made of glass, ceramic, or metal or the like.

[0012] As shown in Fig. 2, the container 40 is formed by laminating a mounting terminal 44, a first substrate 41, a second substrate 42, and a third substrate 43. In the present embodiment, the second substrate 42 is a base on which the vibrating reed 10, that is, the vibrating element 1 is mounted.

[0013] The container 40 has a cavity 48 opening upward. The inside of the cavity 48 that accommodates the vibrating element 1 is hermetically sealed in a reduced-pressure atmosphere or an inert gas atmosphere such as nitrogen by joining a lid 47 with a joining member 50 such as a seal ring.

[0014] A plurality of the mounting terminals 44 are provided on the outer bottom surface of the first substrate 41. Further, the mounting terminals 44 are electrically connected to connection terminals 45 provided above the second substrate 42 via through electrodes or interlayer wirings (not shown).

[0015] The vibrating element 1 is accommodated in the cavity 48 of the container 40. In the vibrating element 1, mount electrodes 23 and 24 provided on a support portion 120 (see Fig. 3) are respectively joined to connection terminals 45 provided on a mounting surface 46 of the second substrate 42 serving as the base via a joining material 51 such as a conductive adhesive, and are electrically connected to the connection terminals 45.

[0016] The joining material 51 comprises a first conductive adhesive and a second conductive adhesive. The first conductive adhesive electrically connects the first excitation electrode 21 to the second substrate 42. The second conductive adhesive electrically connects the second excitation electrode 22 to the second substrate 42. That is, the excitation electrodes 21 and 22 of the vibrating element 1 and the mounting terminals 44 provided on the container 40 are electrically connected to each other via the mount electrodes 23 and 24, the joining material 51, the connection terminals 45, and the like, respectively.

[0017] Next, the configuration of the vibrating element 1 will be described with reference to Fig. 3 and Fig. 4.

[0018] As shown in Fig. 3 and Fig. 4, the vibrating element 1 comprises a vibrating reed 10, a first excitation electrode 21, a second excitation electrode 22, a first mount electrode 23, and a second mount electrode 24.

[0019] The vibrating piece 10 is capable of thickness-shear vibration, and is formed of various piezoelectric materials including a quartz blank. Typically, it is an AT-cut quartz blank, or a double rotation-cut quartz blank represented by an SC-cut. In the present embodiment, the vibrating piece 10 is an AT-cut quartz blank having a quadrangular planar shape, specifically a rectangular planar shape. Therefore, the positive directions of the X-axis, Y-axis, and Z-axis in the figure respectively correspond to the positive directions of the Z'-axis, X-axis, and Y'-axis of the crystal axes of quartz. Note that the present invention is not necessarily limited thereto, and at least any one of the axes may coincide with the negative direction.

[0020] The vibrating piece 10 is a rectangular flat plate having the Y-direction as a longitudinal direction and the X-direction as a width direction. The vibrating piece 10 includes a vibrating portion 110, a support portion 120 disposed spaced apart from the vibrating portion 110, and a connecting portion 130 that connects the vibrating portion 110 and the support portion 120.

[0021] The vibrating portion 110 includes a first main surface 101, a second main surface 102 that is on the opposite side of the first main surface 101, a first side surface 103 connecting the first main surface 101 and the second main surface 102, and a second side surface 104 extending in a direction intersecting the direction in which the first side surface 103 extends.

[0022] The support portion 120 includes a first support side surface 121 disposed opposite to the first side surface 103 of the vibrating portion 110, and a second support side surface 122 extending in a direction intersecting the direction in which the first support side surface 121 extends.

[0023] The connecting portion 130 includes a first connecting surface 131 connected to the first side surface 103 and the first support side surface 121, and a second connecting surface 132 connected to the second side surface 104 and the second support side surface 122.

[0024] The first connecting surface 131 has a curved surface on at least one of a first portion 131A connected to the first side surface 103 and a second portion 131B connected to the first support side surface 121. In the present embodiment, both the first portion 131A and the second portion 131B have curved surfaces.

[0025] Thus, because the first part 131A and the second part 131B have curved surfaces, when an impact is applied to the vibrating piece 10 from the outside, it is possible to suppress the concentration of stress on only one part of the first part 131A and the second part 131B. In other words, it is possible to distribute the concentration of stress, and it is possible to suppress the cracking or damage of the vibrating piece 10.

[0026] A first excitation electrode 21 is provided approximately in the center of the first main surface 101 of the vibrating piece 10. A second excitation electrode 22 is provided approximately in the center of the second main surface 102 of the vibrating piece 10 so as to overlap with the first excitation electrode 21 in a plan view.

[0027] The first excitation electrode 21 is electrically connected to the first mounting electrode 23 via the first lead electrode 21a. The second excitation electrode 22 is electrically connected to the second mounting electrode 24 via the second lead electrode 22a. The first mounting electrode 23 is electrically connected to the first lead electrode 21a via, for example, a through electrode provided through the vibrating piece 10.

[0028] Next, with reference to Figure 5, the manufacturing method of the vibrating element 10 will be explained.

[0029] As shown in Figure 5, first, in step S11, a substrate that will later become the vibrating element 10 is prepared. The substrate is made of a piezoelectric material and is typically an AT-cut quartz substrate or an SC-cut quartz substrate.

[0030] Next, in step S12, a protective film is formed on the substrate. First, a metal film such as gold is deposited on the entire surface of the substrate using a sputtering apparatus or a vapor deposition apparatus. This metal film will function as a protective film for the substrate during the etching process described later.

[0031] Next, a resist is applied to the entire surface of the substrate on which the metal film has been deposited using a spray or spin resist coating apparatus. Then, a photomask is placed on the resist-coated substrate and exposed to light. The resist is developed, and the metal film exposed from the resist is etched to form a protective film that constitutes the outer pattern of the vibrating piece 10.

[0032] Next, in step S13, using the protective film as a mask, the portion of the substrate other than the outline pattern that is exposed is subjected to dry etching using a reactive ion etching apparatus or the like to form the vibrating piece 10. Since it is dry etching, for example, compared to wet etching, the crystal plane of the substrate is less likely to be exposed, resulting in a shape that better reflects the outline pattern, and further reducing the concentration of stress in only a part of the first part 131A or the second part 131B. Note that it is not limited to dry etching, and wet etching may also be used.

[0033] As described above, the vibrating part 110 has a first main surface 101, a second main surface 102 which is in a front-back relationship with the first main surface 101, a first side surface 103 which connects the first main surface 101 and the second main surface 102, and a second side surface 104 which extends in a direction intersecting the direction in which the first side surface 103 extends, and a first support side surface 121 which is spaced apart from the vibrating part 110 and is positioned opposite the first side surface 103 of the vibrating part 110, and extends in a direction intersecting the direction in which the first support side surface 121 extends The vibrating piece 10 is completed, comprising a support portion 120 having a second support side surface 122, a connecting portion 130 having a first connecting surface 131 connected to the first side surface 103 and the first support side surface 121, and a second connecting surface 132 connected to the second side surface 104 and the second support side surface 122, wherein the first connecting surface 131 has curved surfaces on both the first portion 131A connected to the first side surface 103 and the second portion 131B connected to the first support side surface 121.

[0034] As described above, the vibrating piece 10 of this embodiment has a vibrating section 110 having a first main surface 101, a second main surface 102 which is in a front-back relationship with the first main surface 101, a first side surface 103 which connects the first main surface 101 and the second main surface 102, and a second side surface 104 which extends in a direction intersecting the direction in which the first side surface 103 extends, and a first support side surface 121 which is spaced apart from the vibrating section 110 and is positioned opposite the first side surface 103 of the vibrating section 110, and the first support side surface 121 extends The support portion 120 has a second support side surface 122 extending in a direction intersecting the direction, and the connecting portion 130 has a first connecting surface 131 connected to the first side surface 103 and the first support side surface 121, and a second connecting surface 132 connected to the second side surface 104 and the second support side surface 122, wherein the first connecting surface 131 has a curved surface on at least one of the first portion 131A connected to the first side surface 103 and the second portion 131B connected to the first support side surface 121.

[0035] With this configuration, since the first part 131A and the second part 131B have curved surfaces, when an impact is applied to the vibrating piece 10 from the outside, it is possible to suppress the concentration of stress on only one part of the first part 131A and the second part 131B. In other words, it is possible to distribute the concentration of stress, and thus it is possible to suppress the cracking or damage of the vibrating piece 10.

[0036] Furthermore, in the vibrating piece 10 of this embodiment, it is preferable that the first connecting surface 131 has curved surfaces on both the first portion 131A and the second portion 131B. With this configuration, since both the first portion 131A and the second portion 131B have curved surfaces, when an impact is applied to the vibrating piece 10 from the outside, it is possible to suppress the concentration of stress on only one part of the first portion 131A or the second portion 131B, and thus further suppress cracking or damage to the vibrating piece 10.

[0037] Furthermore, the vibration device 100 of this embodiment comprises the vibrating piece 10 described above, a second substrate 42 on which the vibrating piece is mounted, and a container 40 for housing the vibrating piece 10, and the support portion 120 of the vibrating piece 10 is joined to the second substrate 42 via a bonding material 51.

[0038] This configuration makes it possible to provide a vibration device 100 that is less likely to crack or break even when subjected to external impact.

[0039] Furthermore, in the vibration device 100 of this embodiment, it is preferable that the bonding material 51 includes a first conductive adhesive that electrically connects the first excitation electrode 21 provided on the first main surface 101 and the second substrate 42, and a second conductive adhesive that electrically connects the second excitation electrode 22 provided on the second main surface 102 and the second substrate 42. With this configuration, since the bonding material 51 includes the first conductive adhesive and the second conductive adhesive, electrical transmission and reception can be performed between the first excitation electrode 21 and the second excitation electrode 22 and the outside.

[0040] Furthermore, the method for manufacturing the vibrating piece 10 of this embodiment includes preparing a substrate, forming a protective film on the substrate that constitutes an outer shape pattern, and using the protective film as a mask, etching the substrate to form a vibrating piece 10 with an outer shape corresponding to the outer shape pattern, wherein the vibrating piece 10 has a vibrating portion 110 having a first main surface 101, a second main surface 102 that is in a front-back relationship with the first main surface 101, a first side surface 103 that connects the first main surface 101 and the second main surface 102, and a second side surface 104 that extends in a direction intersecting the direction in which the first side surface 103 extends, and spaced apart from the vibrating portion 110 The support portion 120 has a first support side surface 121 positioned opposite the first side surface 103 of the vibrating portion 110, and a second support side surface 122 extending in a direction intersecting the direction in which the first support side surface 121 extends. The connecting portion 130 has a first connecting surface 131 connected to the first side surface 103 and the first support side surface 121, and a second connecting surface 132 connected to the second side surface 104 and the second support side surface 122, wherein the first connecting surface 131 has a curved surface on at least one of a first portion 131A connected to the first side surface 103 and a second portion 131B connected to the first support side surface 121.

[0041] According to this method, since the first part 131A and the second part 131B of the formed vibrating piece 10 have curved surfaces, when an impact is applied to the vibrating piece 10 from the outside, it is possible to suppress the concentration of stress on only one part of the first part 131A and the second part 131B, that is, it is possible to distribute the concentration of stress, and thus it is possible to suppress the cracking or damage of the vibrating piece 10.

[0042] Furthermore, in the manufacturing method of the vibrating piece 10 of this embodiment, the etching process is preferably dry etching. With this method, since it is dry etching, for example, compared to wet etching, the crystal plane of the substrate is less likely to be exposed, resulting in a shape that better reflects the outer shape pattern, and further reducing the concentration of stress in only a part of the first part 131A or the second part 131B.

[0043] The following describes some variations of the embodiments described above.

[0044] As described above, the first connecting surface 131 is not limited to having curved surfaces in both the first portion 131A and the second portion 131B, but may also be as shown in Figures 6 to 10.

[0045] As shown in Figure 6, in the modified vibrating element 1A, the first portion 131A of the vibrating piece 10 is angular rather than curved. Specifically, the first connecting surface 131 is formed at a predetermined angle with the first side surface 103. The second portion 131B is curved, similar to the embodiment described above.

[0046] With this configuration, the first connecting surface 131 forms a predetermined angle with the first side surface 103, that is, the first portion 131A on the vibrating part 110 side is connected at an angle between two planes, which makes it possible to suppress vibration reflection and prevent a deterioration in the characteristic quality of the vibrating piece 10. Furthermore, since the second portion 131B is curved, it is possible to suppress stress concentration in the second portion 131B.

[0047] Furthermore, as shown in the modified example of the vibrating element 1B in Figure 7, the first part 131A may be curved and the second part 131B may be angular.

[0048] Furthermore, as shown in Figure 8, the vibrating piece 10 of the modified vibrating element 1C is formed in a curved shape with a part of the vibrating portion 110 cut out in the first portion 131A of the first connecting surface 131. The second portion 131B is curved, similar to the embodiment described above.

[0049] With this configuration, since the first part 131A has a shape in which a part of the vibrating section 110 is cut out, when an impact is applied to the vibrating piece 10 from the outside, it is possible to suppress the concentration of stress on only one part of the first part 131A, and thus further suppress cracking or damage to the vibrating piece 10.

[0050] Furthermore, as shown in the modified example of the vibrating element 1D in Figure 9, the second portion 131B of the first connecting surface 131 may have a curved shape with a portion of the support portion 120 cut out. Also, as shown in the modified example of the vibrating element 1E in Figure 10, the first portion 131A may be formed with a curved shape with a portion of the vibrating portion 110 cut out, and the second portion 131B may be formed with a curved shape with a portion of the support portion 120 cut out.

[0051] Furthermore, the shape of the vibrating element 10 described above is not limited to having a vibrating portion 110, a support portion 120, and a connecting portion 130, in other words, having a slit shape on one side of the vibrating element 1, but may also be such that it has two slit shapes extending toward the center of the connecting portion 130, that is, from both sides of the vibrating element 1.

[0052] Furthermore, the thickness of the vibrating piece 10 is not limited to being the same in the vibrating section 110, the support section 120, and the connecting section 130. Depending on the strength and characteristic quality of the vibrating piece 10, the thickness may be made different in the first connecting surface 131, the first section 131A, and the second section 131B, respectively. [Explanation of Symbols]

[0053] 1, 1A, 1B, 1C, 1D…Vibrating element, 10…Vibrating piece, 21…First excitation electrode, 21a…First lead electrode, 22…Second excitation electrode, 22a…Second lead electrode, 23…First mounting electrode, 24…Second mounting electrode, 40…Container, 41…First substrate, 42…Second substrate as base, 43…Third substrate, 44…Mounting terminal, 45…Connection terminal, 46…Mounting surface, 47…Lift D, 48...cavity, 50...jointing member, 51...jointing material, 100...vibration device, 101...first main surface, 102...second main surface, 103...first side surface, 104...second side surface, 110...vibrating part, 120...support part, 121...first support side surface, 122...second support side surface, 130...connecting part, 131...first connecting surface, 131A...first part, 131B...second part, 132...second connecting surface.

Claims

1. A vibrating part having a first main surface, a second main surface that is in a front-back relationship with the first main surface, a first side surface connecting the first main surface and the second main surface, and a second side surface extending in a direction intersecting the direction in which the first side surface extends, A support portion having a first support surface positioned at a distance from the vibrating portion and facing the first side surface of the vibrating portion, and a second support surface extending in a direction intersecting the direction in which the first support surface extends, A connecting portion having a first connecting surface connected to the first side surface and the first support side surface, and a second connecting surface connected to the second side surface and the second support side surface, Equipped with, The first connecting surface has a curved surface on at least one of the first portion connected to the first side surface and the second portion connected to the first support side surface. The first connecting surface is a vibrating piece having a shape in which a part of the vibrating portion is cut out in the first portion.

2. A vibrating piece according to claim 1, The first connecting surface is a vibrating piece having curved surfaces in both the first and second portions.

3. A vibrating piece according to claim 1, The first connecting surface is a vibrating piece that, in the second portion, has a shape in which a part of the support portion is cut out.

4. A vibrating piece according to any one of claims 1 to 3, The base on which the vibrating element is mounted, A container for housing the vibrating piece, Equipped with, A vibrating device in which the support portion of the vibrating piece is joined to the base via a bonding material.

5. A vibration device according to claim 4, The bonding material includes a first conductive adhesive that electrically connects a first excitation electrode provided on the first main surface to the base, and a second conductive adhesive that electrically connects a second excitation electrode provided on the second main surface to the base, in a vibration device.

6. Prepare the circuit board, A protective film forming an outer pattern is formed on the substrate, Using the protective film as a mask, the substrate is subjected to an etching process to form a vibrating piece with an external shape corresponding to the external pattern, Includes, The vibrating piece is, A vibrating part having a first main surface, a second main surface that is in a front-back relationship with the first main surface, a first side surface connecting the first main surface and the second main surface, and a second side surface extending in a direction intersecting the direction in which the first side surface extends, A support portion having a first support surface positioned at a distance from the vibrating portion and facing the first side surface of the vibrating portion, and a second support surface extending in a direction intersecting the direction in which the first support surface extends, A connecting portion having a first connecting surface connected to the first side surface and the first support side surface, and a second connecting surface connected to the second side surface and the second support side surface, Equipped with, The first connecting surface has a curved surface on at least one of the first portion connected to the first side surface and the second portion connected to the first support side surface. A method for manufacturing a vibrating piece, wherein the first connecting surface has a shape in which a part of the vibrating portion is cut out in the first portion.

7. A method for manufacturing a vibrating piece according to claim 6, The etching process is dry etching, a method for manufacturing a vibrating piece.

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