Vibrating pieces and vibrating devices

Abstract

To provide a vibrating piece that can improve production efficiency. [Solution] A vibrating piece comprising a piezoelectric substrate, an electrode provided on the piezoelectric substrate, and a bump provided on the surface of the electrode, wherein the bump has a cross-sectional shape in the thickness direction of the piezoelectric substrate, a first portion, and a second portion protruding from the first portion, the first portion having a first side and a second side extending from the surface of the electrode, the second portion having a third side intersecting the first side, and a fourth side intersecting the second side, and the width of the second portion in the direction perpendicular to the thickness direction is greater than the width of the first portion in the direction perpendicular to the thickness direction.

Description

Technical Field

[0001] The present invention relates to a vibrating piece and a vibrating device.

Background Art

[0002] A vibrating device in which a vibrating piece is housed in a package is applied to, for example, a mobile communication device such as a mobile phone.

[0003] For example, Patent Document 1 describes a piezoelectric vibrator including a housing having a base and a lid, a piezoelectric vibrating piece having a bonding member formed on a surface thereof, and bumps for bonding the piezoelectric vibrating piece to the base via the bonding member.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the piezoelectric vibrator as described above, a space is required between the piezoelectric vibrating piece and the base so that the vibration of the piezoelectric vibrating piece is not inhibited by the base. In Patent Document 1, since the bumps are crushed when the piezoelectric vibrating piece is bonded to the base, the bonding member secures the space. However, in Patent Document 1, the process of forming the bonding member increases and the production efficiency decreases.

Means for Solving the Problems

[0006] One aspect of the vibrating piece according to the present invention is a piezoelectric substrate, an electrode provided on the piezoelectric substrate, bumps provided on a surface of the electrode, and includes in a cross-sectional shape in a thickness direction of the piezoelectric substrate, the bumps It has a first part and a second part that protrudes from the first part, The first portion has a first side and a second side extending from the surface of the electrode, The second portion has a third side intersecting the first side and a fourth side intersecting the second side, The width of the second portion in the direction perpendicular to the thickness direction is greater than the width of the first portion in the direction perpendicular to the thickness direction.

[0007] One aspect of the vibration device according to the present invention is: The vibrating piece and, A container having a connection terminal and containing the vibrating element, Includes, The second portion of the bump is connected to the aforementioned connection terminal.

[0008] One aspect of the vibration device according to the present invention is: The vibrating piece and, A container having a connection terminal and containing the vibrating element, The joint member that secures the bump to the connection terminal, Includes, The joining member extends to the corner where the first and third sides of the bump intersect, and to the corner where the second and fourth sides of the bump intersect. [Brief explanation of the drawing]

[0009] [Figure 1] A schematic cross-sectional view showing the vibration device according to the first embodiment. [Figure 2] A schematic plan view showing the vibrating element of the vibration device according to the first embodiment. [Figure 3] A schematic cross-sectional view showing the vibrating element of the vibration device according to the first embodiment. [Figure 4] A schematic cross-sectional view showing the vibrating element of the vibration device according to the first embodiment. [Figure 5] A schematic cross-sectional view showing the vibrating element of the vibration device according to the first embodiment. [Figure 6]Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 7] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 8] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 9] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 10] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 11] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 12] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 13] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 14] Cross-sectional view schematically showing the manufacturing process of the vibrating piece of the vibration device according to the first embodiment. [Figure 15] Plan view schematically showing the vibrating piece of the vibration device according to the modification of the first embodiment. [Figure 16] Cross-sectional view schematically showing the vibration device according to the second embodiment. [Figure 17] Cross-sectional view schematically showing the vibration device according to the first modification of the second embodiment. [Figure 18] Cross-sectional view schematically showing the first bump of the vibration device according to the second modification of the second embodiment. [Figure 19] Cross-sectional view schematically showing the first bump of the vibration device according to the second modification of the second embodiment. [Figure 20] Cross-sectional view schematically showing the first bump of the vibration device according to the second modification of the second embodiment.

Modes for Carrying Out the Invention

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. The embodiments described below are not intended to unduly limit the scope of the present invention as described in the claims. Furthermore, not all of the configurations described below are necessarily essential components of the present invention.

[0011] 1. First Embodiment 1.1. Vibration Devices 1.1.1. Overall structure First, the vibration device according to the first embodiment will be described with reference to the drawings. Figure 1 is a schematic cross-sectional view showing the vibration device 100 according to the first embodiment. In Figure 1, the three mutually orthogonal axes are shown as the X axis, Y axis, and Z axis.

[0012] As shown in Figure 1, the vibration device 100 includes a container 10, a circuit element 20, and a vibrating piece 30. The vibration device 100 is, for example, an oscillator. For convenience, the vibrating piece 30 is simplified in Figure 1.

[0013] The container 10 houses the circuit element 20 and the vibrating element 30. The container 10 is a package. The container 10 has, for example, a base 11, connection terminals 13 and 14, an external terminal 15, and a lid 16.

[0014] The base 11 is made of a ceramic material such as alumina. A recess 12 with an opening on its upper surface is formed in the base 11. The circuit element 20 and the vibrating piece 30 are housed in the space formed by the recess 12. The space of the recess 12 is airtight and under reduced pressure, preferably closer to a vacuum. This reduces viscous resistance and improves the vibration characteristics of the vibrating piece 30. The space of the recess 12 may be filled with an atmosphere of an inert gas such as nitrogen or argon.

[0015] The recess 12 formed in the base 11 includes, for example, a first recess 12a having an opening on the upper surface of the base 11, a second recess 12b formed on the bottom surface of the first recess 12a, and a third recess 12c formed on the bottom surface of the second recess 12b. The opening width of the second recess 12b is smaller than the opening width of the first recess 12a. The opening width of the third recess 12c is smaller than the opening width of the second recess 12b.

[0016] The connection terminal 13 is provided on the bottom surface of the first recess 12a. The connection terminal 14 is provided on the bottom surface of the second recess 12b. The connection terminals 13 and 14 are electrically connected to each other via wiring (not shown). The external terminal 15 is provided on the outer bottom surface of the base 11. The external terminal 15 is electrically connected to the connection terminals 13 and 14 via wiring (not shown). The external terminal 15 is connected to, for example, an external member (not shown). The connection terminals 13 and 14 and the external terminal 15 are laminates formed by stacking nickel (Ni) layers and gold (Au) layers from the base 11 side, for example.

[0017] The lid 16 is joined to the base 11. The joining of the lid 16 to the base 11 is performed, for example, by placing a seal ring 17 on the base 11, placing the lid 16 on the seal ring 17, and welding the seal ring 17 to the base 11 using a resistance welding machine. The joining of the base 11 to the lid 16 is not particularly limited and may be done using an adhesive or by seam welding.

[0018] The material of the lid 16 is, for example, a metal such as Kovar, or a light-transmitting glass. The lid 16 seals the opening of the recess 12. The shape of the lid 16 is, for example, a plate shape.

[0019] The circuit element 20 is bonded to the bottom surface of the third recess 12c. The circuit element 20 includes, for example, an interface section for communicating with an external host device and an oscillation circuit for causing the vibrating piece 30 to oscillate. The circuit element 20 is electrically connected to the connection terminal 14 via wire bonding 18.

[0020] The vibrating element 30 is joined to the connection terminal 13. The vibrating element 30 is electrically connected to the circuit element 20 via the connection terminals 13, 14 and wire bonding 18. When a drive signal is applied from the circuit element 20 to the vibrating element 30, the vibrating element 30 oscillates at a predetermined frequency.

[0021] In this embodiment, the circuit element 20 is provided in the third recess 12c of the base 11, but a semiconductor substrate in which an integrated circuit including an oscillation circuit is formed on a flat silicon substrate (not shown) can also be used. By placing the vibrating piece 30 on the semiconductor substrate and sealing it with a concave lid, the circuit element and the recess of the base become unnecessary, and the vibration device can be miniaturized.

[0022] The vibration device 100 may also be an oscillator with only a vibrating element mounted on a base. In an oscillator not shown, the vibrating element is connected to an oscillation circuit located on an external member via connection terminals and external terminals on the base.

[0023] Furthermore, it may be used as a sensor other than an oscillator or vibrator, such as an acceleration sensor or an angular velocity sensor. The vibration device 100 may be built into computers, printers, smartphones, tablet devices, watches, televisions, head-mounted displays, video cameras, digital still cameras, car navigation systems, electronic game devices, various medical devices, various measuring instruments, various mobile devices, etc.

[0024] 1.1.2. Vibrating piece Figure 2 is a schematic plan view of the vibrating element 30. Figure 3 is a schematic cross-sectional view of the vibrating element 30 taken along line III-III in Figure 2. Figure 4 is a schematic cross-sectional view of the vibrating element 30 taken along line IV-IV in Figure 2. Figure 5 is a schematic cross-sectional view of the vibrating element 30 taken along line VV in Figure 2.

[0025] As shown in Figures 2 to 5, the vibrating element 30 includes, for example, a piezoelectric substrate 40, an electrode 50, a first bump 60a, and a second bump 60b.

[0026] The piezoelectric substrate 40 is, for example, a Z-cut quartz plate. The vibrating element 30 is, for example, a tuning fork-shaped quartz vibrating element. In the illustrated example, the piezoelectric substrate 40 has a flat plate shape that extends in the XY plane defined by the X and Y axes and has thickness in the Z axis direction. The X, Y, and Z axes correspond to the electrical axis, mechanical axis, and optical axis, which are the crystal axes of the quartz, respectively. The constituent material of the piezoelectric substrate 40 is not particularly limited and may be various piezoelectric materials such as lead zirconate titanate.

[0027] As shown in Figure 2, the piezoelectric substrate 40 includes, for example, a base portion 42, a first vibrating arm 44, and a second vibrating arm 46.

[0028] The base 42 supports the first vibrating arm 44 and the second vibrating arm 46. In plan view, the base 42 has a first fixing portion 42a that overlaps with the first bump 60a and a second fixing portion 42b that overlaps with the second bump 60b. In the illustrated example, the fixing portions 42a and 42b have a shape that extends in the X-axis direction. The first fixing portion 42a is located in the +X-axis direction relative to the first vibrating arm 44. The second fixing portion 42b is located in the -X-axis direction relative to the second vibrating arm 46.

[0029] The first vibrating arm 44 and the second vibrating arm 46 extend from the base 42 in the +Y axis direction. In the illustrated example, the first vibrating arm 44 is positioned in the +X axis direction more than the second vibrating arm 46. The vibrating arms 44 and 46 have, for example, a wide section 47 at the end opposite to the base 42, which is wider in the X axis direction. The wide section 47 allows for an increase in the mass of the vibrating arms 44 and 46, thereby enabling miniaturization of the vibrating piece 30.

[0030] Grooves 48 are formed in the first vibrating arm 44 and the second vibrating arm 46. As shown in Figure 4, the grooves 48 are formed in the first main surface 40a and the second main surface 40b of the piezoelectric substrate 40, which face in opposite directions. The grooves 48 give the vibrating arms 44 and 46 a substantially H-shaped cross-section. The grooves 48 can reduce the CI (Crystal Impedance) value of the vibrating piece 30. In the illustrated example, the first main surface 40a faces the -Z axis direction, and the second main surface 40b faces the +Z axis direction.

[0031] The electrode 50 is provided on the piezoelectric substrate 40. The electrode 50 has a first electrode layer 52 and a second electrode layer 54. The first electrode layer 52 and the second electrode layer 54 are spaced apart from each other. The electrode layers 52 and 54 are provided on the main surfaces 40a, 40b and the side surfaces of the base portion 42. Specifically, the first electrode layer 52 is provided on the main surfaces 40a, 40b and the side surfaces of the first fixed portion 42a. The second electrode layer 54 is provided on the main surfaces 40a, 40b and the side surfaces of the second fixed portion 42b. The side surfaces connect the main surfaces 40a and 40b.

[0032] The first electrode layer 52 is further provided on the side surface of the first vibrating arm 44 and on the inner surface of the groove 48 formed in the second vibrating arm 46. The second electrode layer 54 is provided on the inner surface of the groove 48 formed in the first vibrating arm 44 and on the side surface of the second vibrating arm 46.

[0033] Each of the first electrode layer 52 and the second electrode layer 54 has a first metal layer 56 and a second metal layer 58. The first metal layer 56 is provided on the piezoelectric substrate 40. The first metal layer 56 is provided between the piezoelectric substrate 40 and the second metal layer 58. The first metal layer 56 is, for example, a chromium (Cr) layer. The second metal layer 58 is provided on the first metal layer 56. The second metal layer 58 is, for example, a gold layer.

[0034] The first electrode layer 52 is connected to the first bump 60a. The first electrode layer 52 is electrically connected to the circuit element 20 via the first bump 60a. The second electrode layer 54 is connected to the second bump 60b. The second electrode layer 54 is electrically connected to the circuit element 20 via the second bump 60b. When a drive signal is applied from the circuit element 20 to the electrode layers 52 and 54, the first vibrating arm 44 and the second vibrating arm 46 vibrate at a predetermined frequency.

[0035] The first bump 60a is provided between the base 11 and the piezoelectric substrate 40, as shown in Figure 5. The first bump 60a is provided on the surface 50a of the electrode 50. The first bump 60a is joined to the connection terminal 13. The first bump 60a is metal-jointed to the connection terminal 13. The material of the first bump 60a is, for example, a metal such as gold.

[0036] The length L of the first bump 60a in the Z-axis direction is, for example, 10 μm or more and 100 μm or less. The length L corresponds to the thickness of the first bump 60a. The length L and width of the first bump 60a, which will be described later, are measured, for example, by SEM (Scanning Electron Microscope). As shown in Figure 5, the first bump 60a has a cross-sectional shape in the Z-axis direction, which is the thickness direction of the piezoelectric substrate 40, and comprises a first portion 62 and a second portion 64.

[0037] The first portion 62 of the first bump 60a is provided between the second portion 64 and the piezoelectric substrate 40. The first portion 62 is in contact with the first electrode layer 52 of the electrode 50. The first portion 62 has a first side 62a and a second side 62b extending from the surface 50a of the electrode 50. In the illustrated example, the first side 62a and the second side 62b extend from the surface 50a of the electrode 50 in the +Z axis direction. The first side 62a and the second side 62b are perpendicular to the surface 50a. The first side 62a and the second side 62b are, for example, parallel to each other. In the illustrated example, the shape of the first portion 62 is rectangular.

[0038] The second portion 64 of the first bump 60a is provided between the connection terminal 13 and the first portion 62. The second portion 64 protrudes from the first portion 62 on the side opposite to the first electrode layer 52. In the illustrated example, the second portion 64 protrudes from the first portion 62 in the +Z axis direction. The second portion 64 is connected to the connection terminal 13. The width W2 of the second portion 64 is greater than the width W1 of the first portion 62. The widths W1 and W2 are in directions perpendicular to the thickness direction of the piezoelectric substrate 40. Width W1 is the maximum width in the first portion 62. Width W2 is the maximum width in the second portion 64. The width W2 of the second portion 64 is greater than the length of the second portion 64 in the Z axis direction. The length of the second portion 64 in the Z axis direction is less than the length of the first portion 62 in the Z axis direction.

[0039] The second portion 64 of the first bump 60a has a third side 64a that intersects the first side 62a and a fourth side 64b that intersects the second side 62b. In the illustrated example, the angle θ1 at which the first side 62a and the third side 64a intersect is 90°. The angle θ2 at which the second side 62b and the fourth side 64b intersect is 90°. Note that angles θ1 and θ2 are the angles at which the surface of the first portion 62 intersects with the surface of the second portion 64. The third side 64a and the fourth side 64b are, for example, parallel to the surface 50a of the electrode 50. In the illustrated example, the shape of the second portion 64 is rectangular.

[0040] The second bump 60b is connected to the second electrode layer 54. The shape and material of the second bump 60b are basically the same as those of the first bump 60a. Therefore, a description of it is omitted.

[0041] Furthermore, the vibrating element 30 is not limited to a tuning fork type vibrating element, but may be, for example, an AT vibrating element.

[0042] 1.1.3. Method for manufacturing a vibrating piece Next, the manufacturing method of the vibrating element 30 will be explained with reference to the drawings. Figures 6 to 14 are schematic cross-sectional views showing the manufacturing process of the vibrating element 30. Figures 6 to 11 correspond to the cross-sectional view along line III-III shown in Figure 2. Figures 12 to 14 correspond to the cross-sectional view along line VV shown in Figure 2.

[0043] As shown in Figure 6, a mask layer 70 is formed on the first main surface 40a and the second main surface 40b of the piezoelectric substrate 40. Specifically, a chromium layer 72 is formed on the piezoelectric substrate 40, and a gold layer 74 is formed on the chromium layer 72 to form a mask layer 70 having the chromium layer 72 and the gold layer 74. The chromium layer 72 and the gold layer 74 are formed, for example, by sputtering.

[0044] As shown in Figure 7, the mask layer 70 is patterned. Patterning is performed, for example, by photolithography and etching.

[0045] As shown in Figure 8, a first resist layer 80 is formed on the mask layer 70. The first resist layer 80 is formed into a predetermined shape, for example, by photolithography.

[0046] As shown in Figure 9, the piezoelectric substrate 40 is etched using the mask layer 70 as a mask. This etching process forms the outer shape of the piezoelectric substrate 40.

[0047] As shown in Figure 10, the mask layer 70 is etched using the first resist layer 80 as a mask, and then the piezoelectric substrate 40 is etched to form grooves 48. Next, the first resist layer 80 is peeled off and the mask layer 70 is etched and removed.

[0048] As shown in Figure 11, electrodes 50 are formed on the piezoelectric substrate 40. The electrodes 50 are formed, for example, by sputtering. Next, a second resist layer 82 is formed on the electrodes 50. The second resist layer 82 is formed into a predetermined shape, for example, by photolithography. Next, the electrodes 50 are etched using the second resist layer 82 as a mask to form the first electrode layer 52 and the second electrode layer 54.

[0049] As shown in Figure 3, the second resist layer 82 is peeled off.

[0050] As shown in Figure 12, a third resist layer 84 is formed on the electrode 50. The third resist layer 84 is formed into a predetermined shape, for example, by photolithography.

[0051] As shown in Figure 13, a first bump 60a is formed on the first electrode layer 52. The first bump 60a is formed, for example, by an electroless plating method. In the illustrated example, the first portion 62 of the first bump 60a is surrounded by the third resist layer 84. The second portion 64 of the first bump 60a protrudes from the third resist layer 84. The length of the first bump 60a in the Z-axis direction is longer than the thickness of the third resist layer 84. In the illustrated example, the second portion 64 has an arc shape near its tip.

[0052] As shown in Figure 14, the third resist layer 84 is peeled off. Then, the first bump 60a is placed on the connection terminal 13.

[0053] As shown in Figure 5, the first bump 60a is metal-bonded to the connection terminal 13 of the container 10. This metal bonding is performed by applying pressure to the connection terminal 13 while heating it. This metal bonding is performed, for example, when the connection terminal 13 is at a higher temperature than the first bump 60a. Since the second portion 64 is wider than the first portion 62, heat is easily transferred from the connection terminal 13. Therefore, as shown in Figure 5, the second portion 64 can be selectively crushed, while the first portion 62 can remain uncrushed.

[0054] The second bump 60b is formed on the second electrode layer 54 in the same manner and process as the first bump 60a. Then, the second bump 60b is joined to the container 10 in the same way as the first bump 60a.

[0055] As a result, the vibrating piece 30 joined to the container 10 can be manufactured.

[0056] 1.1.4. Effects The vibrating piece 30 includes a piezoelectric substrate 40, an electrode 50 provided on the piezoelectric substrate 40, and a first bump 60a provided on the surface 50a of the electrode 50. The first bump 60a has a cross-sectional shape in the thickness direction of the piezoelectric substrate 40, a first portion 62, and a second portion 64 protruding from the first portion 62. The first portion 62 has a first side 62a and a second side 62b extending from the surface 50a of the electrode 50. The second portion 64 has a third side 64a intersecting the first side 62a, and a fourth side 64b intersecting the second side 62b. The width W2 of the second portion 64 is greater than the width W1 of the first portion 62.

[0057] Therefore, in the vibrating piece 30, the first portion 62 of the first bump 60a ensures space between the piezoelectric substrate 40 and the connection terminal 13 of the container 10. Consequently, there is no need to provide a separate spacer between the bump 60 and the electrode 50. Thus, compared to the case where a separate spacer is provided, the manufacturing process can be reduced and production efficiency can be improved.

[0058] Furthermore, in the vibrating piece 30, as described above, the second portion 64 of the first bump 60a is selectively crushed when joining with the connection terminal 13, thereby suppressing the amount of indentation of the first bump 60a during joining. As a result, the bonding strength can be improved while ensuring space between the piezoelectric substrate 40 and the connection terminal 13.

[0059] In the vibrating piece 30, the third side 64a and the fourth side 64b are parallel to the surface 50a of the electrode 50. Therefore, in the vibrating piece 30, the thickness of the first portion 62 in the first bump 60a is set to the thickness of the third resist layer 84, and the first bump 60a can be formed thicker than the third resist layer 84 due to the presence of the second portion 64.

[0060] 1.1.5. Variations of the vibrating piece Next, a vibrating piece according to a modified example of the first embodiment will be described with reference to the drawings. Figure 15 is a schematic plan view showing a vibrating piece 130 according to a modified example of the first embodiment. Hereinafter, in the vibrating piece 130 according to a modified example of the first embodiment, components having the same function as the components of the vibrating piece 30 according to the first embodiment described above will be denoted by the same reference numerals, and their detailed descriptions will be omitted.

[0061] In the vibrating piece 30 described above, as shown in Figure 2, one first bump 60a was provided relative to the first fixed part 42a. One second bump 60b was provided relative to the second fixed part 42b.

[0062] In contrast, in the vibrating piece 130, as shown in Figure 15, multiple first bumps 60a are provided on the first fixed part 42a. Multiple second bumps 60b are provided on the second fixed part 42b. In the illustrated example, three first bumps 60a are provided on the first fixed part 42a. Three second bumps 60b are provided on the second fixed part 42b.

[0063] In the vibrating element 130, multiple first bumps 60a are provided. Therefore, the contact area between the first bumps 60a and the first electrode layer 52 can be increased in the vibrating element 130. This improves the bonding strength between the vibrating element 130 and the container 10. Furthermore, the flatness of the piezoelectric substrate 40 can be improved.

[0064] 2. Second Embodiment 2.1. Vibration Devices Next, the vibration device according to the second embodiment will be described with reference to the drawings. Figure 16 is a schematic cross-sectional view showing the vibration device 200 according to the second embodiment. Hereinafter, in the vibration device 200 according to the second embodiment, components having the same function as the components of the vibration device 100 according to the first embodiment described above will be denoted by the same reference numerals, and their detailed descriptions will be omitted.

[0065] The vibration device 200 differs from the vibration device 100 described above in that it includes a connecting member 90, as shown in Figure 16.

[0066] For example, silver paste is used as the joining member 90. The joining member 90 is softer than the first bump 60a. The Young's modulus of the joining member 90 is smaller than, for example, the Young's modulus of the first bump 60a.

[0067] In the vibration device 200, the vibrating piece 30 is placed on the connection terminal 13 without the second portion 64 of the first bump 60a being crushed. The first bump 60a is not heat-pressed to the connection terminal 13. The first bump 60a is not metal-bonded to the connection terminal 13. In the vibration device 200, with the first bump 60a placed on the connection terminal 13, a paste-like bonding member 90 is applied, and then the bonding member 90 is hardened by heating, thereby fixing the vibrating piece 30 to the container 10.

[0068] The joining member 90 fixes the first bump 60a to the connecting terminal 13. As shown in Figure 16, the joining member 90 extends to the first corner 66 and the second corner 68 of the first bump 60a in the cross-sectional shape in the Z-axis direction. The joining member 90 covers the first corner 66 and the second corner 68. The first corner 66 is the part where the first side 62a and the third side 64a of the first bump 60a intersect. The second corner 68 is the part where the second side 62b and the fourth side 64b of the first bump 60a intersect.

[0069] The joining member 90 is separated from the first electrode layer 52. The length L of the first bump 60a in the Z-axis direction is, for example, 20 μm or more. The length L of the first bump 60a is, for example, greater than the width W2 of the second portion 64 of the first bump 60a.

[0070] In the vibration device 200, for example, the second bump 60b is also fixed to the container 10 by a connecting member 90, similar to the first bump 60a.

[0071] In the vibration device 200, the length L of the first bump 60a is 20 μm or more. Therefore, in the vibration device 200, when the vibrating piece 30 is fixed to the container 10, the possibility of the bonding member 90 adhering to the electrode 50 can be reduced. This reduces the possibility of the bonding member 90 adhering to the piezoelectric substrate 40.

[0072] In the vibration device 200, the joining member 90 reaches the first corner 66 where the first side 62a and the third side 64a of the first bump 60a intersect, and the second corner 68 where the second side 62b and the fourth side 64b of the first bump 60a intersect. Therefore, in the vibration device 200, the anchoring effect caused by the joining member 90 penetrating the corners 66 and 68 of the first bump 60a improves the bonding strength of the vibrating piece 30 to the container 10. Consequently, since the bonding strength is sufficiently large even without increasing the size of the first bump 60a, miniaturization can be achieved.

[0073] Furthermore, since the joining member 90 is softer than the first bump 60a, it can absorb the stress generated by the joining of the vibrating piece 30 and the container 10, compared to the case where the second portion 64 is crushed to join the vibrating piece 30 to the container 10, as in the vibration device 100. This suppresses vibration leakage from the piezoelectric substrate 40.

[0074] 2.2. Variations of vibration devices 2.2.1. First Variation Next, a vibration device according to the first modified example of the second embodiment will be described with reference to the drawings. Figure 17 is a schematic cross-sectional view showing a vibration device 210 according to the first modified example of the second embodiment.

[0075] In the following description of the vibration device 210 according to the first modified example of the second embodiment, components having the same function as the components of the vibration device 200 according to the second embodiment described above are denoted by the same reference numerals, and their detailed descriptions are omitted. The same applies to the vibration device according to the second modified example of the second embodiment, which will be described later.

[0076] In the vibration device 200 described above, as shown in Figure 16, the bonding member 90 was separated from the first electrode layer 52.

[0077] In contrast, in the vibration device 210, as shown in Figure 17, the joining member 90 is in contact with the first electrode layer 52. Therefore, in the vibration device 210, the contact area between the joining member 90 and the vibrating piece 30 can be increased. This improves the bonding strength between the vibrating piece 30 and the container 10.

[0078] 2.2.2. Second Variation Next, a vibration device according to a second modified example of the second embodiment will be described with reference to the drawings. Figure 18 is a schematic cross-sectional view showing the first bump 60a of the vibration device 220 according to a second modified example of the second embodiment.

[0079] In the vibration device 220, the shape of the first bump 60a is different from the shape of the first bump 60a in the vibration device 200 described above.

[0080] In the vibration device 210, as shown in Figure 18, at least one of the angles θ1 where the first side 62a and the third side 64a intersect, and θ2 where the second side 62b and the fourth side 64b intersect, is less than 90°. In the illustrated example, both angles θ1 and θ2 are less than 90°. Angles θ1 and θ2 are, for example, 45° or more and less than 90°. If at least one of angles θ1 and θ2 is less than 90°, the anchoring effect is enhanced when the vibrating piece 30 is fixed to the container 10 with the joining member 90, thereby improving the bonding strength between the vibrating piece 30 and the container 10.

[0081] As shown in Figure 19, at least one of angles θ1 and θ2 may be 90° or greater. At least one of angles θ1 and θ2 may be greater than 90°. In the illustrated example, both angles θ1 and θ2 are greater than 90°. Angles θ1 and θ2 are, for example, between 90° and 135°. If at least one of angles θ1 and θ2 is 90° or greater, the strength of the first portion 62 of the first bump 60a can be increased, and the space between the connection terminal 13 of the container 10 and the first electrode layer 52 can be stably secured.

[0082] The magnitudes of the angles θ1 and θ2 can be controlled by the type of third resist layer 84 and the amount of exposure to the third resist layer 84.

[0083] Furthermore, the width W2 of the second portion 64 of the first bump 60a is not particularly limited. For example, the width W2 of the first bump 60a shown in Figure 20 is smaller than the width W2 of the first bump 60a shown in Figure 18. The width W2 is controlled, for example, by the plating time when forming the first bump 60a.

[0084] The embodiments and variations described above are examples only and are not limited thereto. For example, each embodiment and each variation can be combined as appropriate.

[0085] The present invention includes configurations substantially identical to those described in the embodiments, for example, configurations with the same function, method, and results, or configurations with the same purpose and effect. Furthermore, the present invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Furthermore, the present invention includes configurations that produce the same effects or achieve the same purpose as those described in the embodiments. Finally, the present invention includes configurations that add known technology to the configurations described in the embodiments.

[0086] The following can be derived from the embodiments and modifications described above.

[0087] One aspect of the vibrating element is, Piezoelectric substrate and An electrode provided on the piezoelectric substrate, Bumps provided on the surface of the electrode, Includes, The bump has a cross-sectional shape in the thickness direction of the piezoelectric substrate, It has a first part and a second part that protrudes from the first part, The first portion has a first side and a second side extending from the surface of the electrode, The second portion has a third side intersecting the first side and a fourth side intersecting the second side, The width of the second portion in the direction perpendicular to the thickness direction is greater than the width of the first portion in the direction perpendicular to the thickness direction.

[0088] This vibrating element can improve production efficiency.

[0089] In one embodiment of the vibrating piece, The third and fourth sides may be parallel to the surface of the electrode.

[0090] This vibrating element allows for the formation of bumps that are thicker than the resist layer used to form them.

[0091] In one embodiment of the vibrating piece, At least one of the angles at which the first side and the third side intersect, and the angles at which the second side and the fourth side intersect, may be less than 90°.

[0092] This vibrating element allows for improved bonding strength between the vibrating element and the container when the element is joined to the container.

[0093] In one embodiment of the vibrating piece, At least one of the angles at which the first side and the third side intersect, and the angles at which the second side and the fourth side intersect, may be 90° or greater.

[0094] This vibrating element allows for increased strength in the first section.

[0095] In one embodiment of the vibrating piece, The length of the bump in the thickness direction may be 20 μm or more.

[0096] This vibrating element reduces the possibility of the connecting member adhering to the electrode when the vibrating element is joined to the container using a connecting member.

[0097] In one embodiment of the vibrating piece, Multiple bumps may be provided.

[0098] This vibrating element allows for improved bonding strength between the vibrating element and the container when the element is joined to the container.

[0099] One embodiment of a vibration device is, In one embodiment of the vibrating piece, One embodiment of the vibrating piece, A container having a connection terminal and containing the vibrating element, Includes, The second portion of the bump is connected to the aforementioned connection terminal.

[0100] This vibration device can improve production efficiency.

[0101] One embodiment of a vibration device is, One embodiment of the vibrating piece, A container having a connection terminal and containing the vibrating element, The joint member that secures the bump to the connection terminal, Includes, The joining member extends to the corner where the first and third sides of the bump intersect, and to the corner where the second and fourth sides of the bump intersect.

[0102] This vibration device can improve production efficiency. [Explanation of Symbols]

[0103] 10...Container, 11...Base, 12...Recess, 12a...First recess, 12b...Second recess, 12c...Third recess, 13,14...Connecting terminals, 15...External terminal, 16...Lid, 17...Seal ring, 18...Wire bonding, 20...Circuit element, 30...Vibrating piece, 40...Piezoelectric substrate, 40a...First main surface, 40b...Second main surface, 42...Base, 42a...First fixing part, 42b...Second fixing part, 44...First vibrating arm, 46...Second vibrating arm, 47...Wide part, 48...Groove, 50...Electrode, 50a...Surface, 52...First electrode Layers, 54...Second electrode layer, 56...First metal layer, 58...Second metal layer, 60a...First bump, 60b...Second bump, 62...First part, 62a...First edge, 62b...Second edge, 64...Second part, 64a...Third edge, 64b...Fourth edge, 66...First corner, 68...Second corner, 70...Mask layer, 72...Chromium layer, 74...Gold layer, 80...First resist layer, 82...Second resist layer, 84...Third resist layer, 90...Bonding member, 100...Vibration device, 130...Vibrating piece, 200, 210, 220...Vibration device

Claims

1. Piezoelectric substrate and An electrode provided on the piezoelectric substrate, Bumps provided on the surface of the electrode, Includes, The bump has a cross-sectional shape in the thickness direction of the piezoelectric substrate, It has a first part and a second part that protrudes from the first part, The first portion has a first side and a second side extending from the surface of the electrode, The second portion has a third side intersecting the first side and a fourth side intersecting the second side, A vibrating piece wherein the width of the second portion in the direction perpendicular to the thickness direction is greater than the width of the first portion in the direction perpendicular to the thickness direction.

2. In claim 1, A vibrating piece, the third and fourth sides of which are parallel to the surface of the electrode.

3. In claim 1 or 2, A vibrating piece in which at least one of the angles at which the first side and the third side intersect, and the angles at which the second side and the fourth side intersect, is less than 90°.

4. In claim 1 or 2, A vibrating piece in which at least one of the angles at which the first side and the third side intersect, and the angles at which the second side and the fourth side intersect, is 90° or more.

5. In claim 1 or 2, A vibrating piece having a length of 20 μm or more in the thickness direction of the bump.

6. In claim 1 or 2, The aforementioned bump consists of multiple vibrating pieces.

7. A vibrating piece according to claim 1 or 2, A container having a connection terminal and containing the vibrating element, Includes, A vibration device to which the second portion of the bump is connected to the aforementioned connection terminal.

8. A vibrating piece according to claim 1 or 2, A container having a connection terminal and containing the vibrating element, The joint member that secures the bump to the connection terminal, Includes, The connecting member extends to the corner where the first and third sides of the bump intersect, and to the corner where the second and fourth sides of the bump intersect, in a vibration device.

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