Vibration device

Abstract

To provide a vibration device in which strain due to implementation of a vibration element or stress due to temperature change is suppressed.SOLUTION: A vibration device 1 includes a vibration element 3 having a first surface 31 where a first connection electrode 36 and a second connection electrode 37 are disposed, a substrate 10 having a third surface 13 facing the first surface 31 of the vibration element 3, where a first electrode pad 11 and a second electrode pad 12 are disposed, a first metal bump 41 to bond the first connection electrode 36 and the first electrode pad 11, a second metal bump 42 to bond the second connection electrode 37 and the second electrode pad 12, and a non-conductive resin 40 that overlaps with at least a part of a region including the first metal bump 41 and the second metal bump 42 in a plan view and bonds the vibration element 3 and the substrate 10. When the length of the vibration element 3 is L1, the length of the first metal bump 41 is L2, the length of the second metal bump 42 is L3, and the distance between an outer edge of the first metal bump 41 and an outer edge of the second metal bump 42 is D, L2+L3<D≤L1 / 2 is satisfied.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a vibration device. [Background technology]

[0002] For example, Patent Document 1 discloses a quartz crystal device in which an insulating adhesive is used to bond the quartz crystal element to a substrate, and a conductive adhesive is applied from the top surface of the quartz crystal element to the electrode pads of the substrate, thereby electrically connecting the connection electrodes on the top surface of the quartz crystal element to the electrode pads of the substrate. The insulating adhesive that bonds the quartz crystal element to the substrate has a stronger adhesive force than the conductive adhesive, so a smaller amount of adhesive is needed to ensure the bonding strength between the quartz crystal element and the substrate compared to bonding with a conductive adhesive. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-120264 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the crystal device described in Patent Document 1, the two connection electrodes of the crystal element are provided at the corners at both ends of one side of the crystal element, and are fixed to the substrate at two separate points. Therefore, there is a risk that stress will easily occur due to distortion when the insulating adhesive or conductive adhesive hardens or due to differences in the linear expansion coefficient with the substrate, which may cause the frequency to fluctuate. [Means for solving the problem]

[0005] The vibration device includes a vibration element having excitation electrodes, a first surface on which a first connection electrode and a second connection electrode connected to the excitation electrodes are disposed, and a second surface having a front-back relationship with the first surface, a substrate having a third surface facing the first surface of the vibration element and on which a first electrode pad and a second electrode pad are disposed, a first metal bump that joins and electrically connects the first connection electrode and the first electrode pad, a second metal bump that joins and electrically connects the second connection electrode and the second electrode pad, a non-conductive resin that overlaps at least a part of a region including the first metal bump and the second metal bump in a plan view and joins the vibration element and the substrate. When the length of the vibration element along the direction in which the first metal bump and the second metal bump are arranged is L1, the length of the first metal bump along the direction is L2, the length of the second metal bump along the direction is L3, and the distance between the outer edge of the first metal bump on the side opposite to the second metal bump side and the outer edge of the second metal bump on the side opposite to the first metal bump side is D, L2 + L3 < D ≦ L1 / 2 is satisfied.

Brief Description of the Drawings

[0006] [Figure 1] A plan view showing a schematic structure of a vibration device according to a first embodiment. [Diagram 2] A cross-sectional view taken along line A1-A1 in FIG. 1. [Diagram 3] A plan view for explaining the positional relationship between the vibration element and the metal bump. [Figure 4] A cross-sectional view showing a schematic structure of a vibration device according to a second embodiment. [Diagram 5] A cross-sectional view showing a schematic structure of a vibration device according to a third embodiment. [Figure 6] A plan view showing a schematic structure of a vibration device according to a fourth embodiment. [Figure 7] A cross-sectional view taken along line A2-A2 in FIG. 6. [Figure 8] A plan view showing a schematic structure of a vibration device according to a fifth embodiment. [Figure 9] A cross-sectional view taken along line A3-A3 in FIG. 8. [Figure 10] FIG. 13 is a plan view showing a schematic structure of a vibration device according to a sixth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] 1. First embodiment First, a resonator in which a resonator element 3 is housed between a substrate 10 and a lid 20 will be described with reference to FIGS. 1, 2, and 3 as an example of a resonator device 1 according to a first embodiment. In FIG. 1, for the sake of convenience in explaining the internal configuration of the vibration device 1, the cover 20 is removed. For the sake of convenience in explanation, each of the following figures illustrates three mutually perpendicular axes: an X axis, a Y axis, and a Z axis. The direction along the X axis is called the "X direction", the direction along the Y axis is called the "Y direction", and the direction along the Z axis is called the "Z direction". The tip side of the arrow in each axial direction is also called the "plus side", the base end side is called the "minus side", and the plus side of the Z direction is called the "upper".

[0008] As shown in FIGS. 1 and 2, the vibration device 1 includes a substrate 10, a lid 20, a vibration element 3, a first metal bump 41, a second metal bump 42, and a non-conductive resin 40.

[0009] The substrate 10 has a third surface 13 and a fourth surface 14, which are opposite surfaces, and the third surface 13 faces the first surface 31 of the vibration element 3. On the third surface 13, a first electrode pad 11 and a second electrode pad 12 for bonding the vibration element 3 are arranged side by side along the Y direction, and on the fourth surface 14, a plurality of external terminals 15 used for supplying power and outputting frequencies are provided. The first electrode pad 11 and the second electrode pad 12 are electrically connected to the external terminals 15 by wiring or through electrodes (not shown). Silicon is suitable as a constituent material of the substrate 10, but glass, ceramic, etc. may also be used.

[0010] The lid 20 is provided with a recess 21 that opens to the substrate 10 side, and is joined to the third surface 13 of the substrate 10 via a joining member 25, and together with the substrate 10, forms an accommodation space 22 that accommodates the vibration element 3. The lid 20 and the substrate 10 may be joined directly without using the joining member 25. The accommodation space 22 is in a reduced pressure state, preferably a state closer to a vacuum. This reduces viscous resistance and improves the oscillation characteristics of the vibration element 3. Silicon is a suitable material for the lid 20, but glass, ceramics, etc. may also be used.

[0011] The vibration element 3 has a vibration substrate 30, an excitation electrode 33, a first connection electrode 36, and a second connection electrode 37. The vibration substrate 30 is rectangular in plan view, with the X direction as the long side direction, the Y direction as the short side direction, and the Z direction as the thickness direction. The vibration substrate 30 has a first surface 31 and a second surface 32, which are opposite sides, and the first surface 31 faces the third surface 13 of the substrate 10. The first surface 31 is provided with an excitation electrode 33, and a first connection electrode 36 and a second connection electrode 37 on the negative side of the excitation electrode 33 in the X direction, and the second surface 32 is provided with the excitation electrode 33. The excitation electrode 33 provided on the first surface 31 is electrically connected to the first connection electrode 36 via a lead electrode 34. The excitation electrode 33 provided on the second surface 32 is electrically connected to the second connection electrode 37 provided on the first surface 31 via the lead electrode 34 and a side electrode 35 provided on the side surface of the vibration substrate 30 on the negative side in the X direction. The excitation electrodes 33 provided on the first surface 31 and the excitation electrodes 33 provided on the second surface 32 are arranged so as to overlap each other in a plan view. The vibration substrate 30 is made of quartz crystal, and an AT-cut quartz crystal substrate is preferable.

[0012] The first metal bump 41 and the second metal bump 42 are arranged side by side along the Y direction which is the short side direction of the vibration element 3. The first metal bump 41 joins and electrically connects the first connection electrode 36 and the first electrode pad 11. The second metal bump 42 joins and electrically connects the second connection electrode 37 and the second electrode pad 12. Also, the first metal bump 41 and the second metal bump 42 are arranged at the center in the short side direction at the end on the minus side in the X direction of the rectangular vibration element 3 together with the non-conductive resin 40.

[0013] As shown in FIG. 3, the positional relationship between the vibration element 3, the first metal bump 41, and the second metal bump 42 is such that, with respect to the length of the vibration element 3 along the Y direction (the direction in which the first metal bump 41 and the second metal bump 42 are arranged side by side) being L1, the length of the first metal bump 41 along the Y direction being L2, the length of the second metal bump 42 along the Y direction being L3, and the distance between the outer edge of the first metal bump 41 on the side opposite to the second metal bump 42 side and the outer edge of the second metal bump 42 on the side opposite to the first metal bump 41 side being D, L2 + L3 < D ≦ L1 / 2 is satisfied. That is, the distance D between the outer edge of the first metal bump 41 and the outer edge of the second metal bump 42 is greater than L2 + L3 and is less than or equal to half of the length L1 in the short side direction of the vibration element 3. Therefore, compared with the case where they are joined at both ends in the short side direction of the vibration element 3, the interval between the two joining positions becomes shorter, so that the influence of the stress accompanying the temperature change caused by the difference in the linear expansion coefficients between the vibration element 3 and the substrate 10 can be suppressed.

[0014] In particular, by joining the vibration element 3 and the substrate 10 using the first metal bump 41 and the second metal bump 42, since there is no spreading like a conductive adhesive, the first metal bump 41 and the second metal bump 42 can be arranged closer to each other, and the influence of the stress accompanying the temperature change can be suppressed more effectively. Incidentally, the constituent materials of the first metal bump 41 and the second metal bump 42 are Au, Cu, Sn-Pd alloy, etc.

[0015] The non-conductive resin 40 is a non-conductive adhesive, which overlaps at least a part of the region including the first metal bump 41 and the second metal bump 42 in a plan view, and joins the vibration element 3 and the substrate 10. Further, the non-conductive resin 40 is disposed from the second surface 32 of the vibration element 3 to the third surface 13 of the substrate 10. By using the non-conductive resin 40 that can increase the bonding area and enhance the bonding strength compared with the first metal bump 41 and the second metal bump 42, and further joining the vibration element 3 and the substrate 10, the bonding strength between the vibration element 3 and the substrate 10 can be further improved. Incidentally, the constituent material of the non-conductive resin 40 is a silicone resin, an epoxy resin, a polyimide resin, or the like.

[0016] As described above, in the vibration device 1 of the present embodiment, in the short side direction of the vibration element 3, the relationship between the length L1 of the vibration element 3, the lengths L2 and L3 of the first metal bump 41 and the second metal bump 42, and the distance D between the outer edge on the side opposite to the second metal bump 42 side of the first metal bump 41 and the outer edge on the side opposite to the first metal bump 41 side of the second metal bump 42 satisfies L2 + L3 < D ≦ L1 / 2. Therefore, the distance between the first metal bump 41 and the second metal bump 42 can be shortened, and the influence of the strain generated during the joining of the vibration element 3 to the substrate 10 and the stress accompanying the temperature change on the vibration element 3 can be suppressed.

[0017] Further, since the first metal bump 41 and the second metal bump 42 are used for the mechanical and electrical joining between the vibration element 3 and the substrate 10, there is no risk of spreading like a conductive adhesive. Therefore, it is possible to bring the distance between the first connection electrode 36 and the second connection electrode 37 of the vibration element 3 and the distance between the first electrode pad 11 and the second electrode pad 12 of the substrate 10 closer, and suppress the strain generated by the joining of the vibration element 3 to the substrate 10 and the stress accompanying the temperature change.

[0018] Furthermore, since the vibration element 3 and the substrate 10 are also joined by the non-conductive resin 40, the bonding strength between the vibration element 3 and the substrate 10 can be sufficiently ensured.

[0019] 2. Second Embodiment Next, a vibration device 1a according to a second embodiment will be described with reference to FIG.

[0020] The resonator device 1a of this embodiment is similar to the resonator device 1 of the first embodiment, except that the position of the non-conductive resin 40a is different from that of the resonator device 1 of the first embodiment. Note that the following description will focus on the differences from the first embodiment, and will omit a description of the similar points.

[0021] 4, in the vibration device 1a, the non-conductive resin 40a overlaps at least a part of the region including the first metal bump 41 and the second metal bump 42 in a plan view, and bonds the vibration element 3 and the substrate 10. The non-conductive resin 40 is disposed from the second surface 32 of the vibration element 3 to the third surface 13 of the substrate 10, and is also disposed on the first surface 31 of the vibration element 3. Therefore, the bonding area between the vibration element 3 and the substrate 10 by the non-conductive resin 40 is increased, and the bonding strength between the vibration element 3 and the substrate 10 can be further improved.

[0022] With this configuration, the bonding strength between the vibration element 3 and the substrate 10 can be further improved, and the same effects as those of the first embodiment can be obtained.

[0023] 3. Third embodiment Next, a vibration device 1b according to a third embodiment will be described with reference to FIG.

[0024] The resonator device 1b of this embodiment is similar to the resonator device 1 of the first embodiment, except that the position of the non-conductive resin 40b is different from that of the resonator device 1 of the first embodiment. Note that the following description will focus on the differences from the first embodiment, and will omit the description of the similar points.

[0025] 5, in the resonator device 1b, the non-conductive resin 40b is an underfill, and the non-conductive resin 40b is disposed between the first surface 31 of the resonator element 3 and the third surface 13 of the substrate 10. Therefore, the bonding area of ​​the non-conductive resin 40b can be reduced, and stress caused by temperature changes can be reduced. In addition, since the non-conductive resin 40b is also disposed around the first metal bump 41 and the second metal bump 42, the first metal bump 41 and the second metal bump 42 can be protected.

[0026] With this configuration, the bonding area of ​​the non-conductive resin 40b is reduced, which reduces the stress caused by temperature changes, and the metal bumps 41 and 42 can be protected, and further, the same effects as those of the first embodiment can be obtained.

[0027] 4. Fourth embodiment Next, a vibration device 1c according to a fourth embodiment will be described with reference to Fig. 6 and Fig. 7. In Fig. 6, for the sake of convenience in describing the internal configuration of the vibration device 1c, a state in which the lid 20 is removed is illustrated.

[0028] The resonator device 1c of this embodiment is similar to the resonator device 1 of the first embodiment, except that the number of first metal bumps 41c and second metal bumps 42c is different from that of the resonator device 1 of the first embodiment. Note that the following description will focus on the differences from the first embodiment, and descriptions of similar matters will be omitted.

[0029] As shown in Figures 6 and 7, in the vibration device 1c, the first connection electrode 36 and the first electrode pad 11 are joined and electrically connected by a plurality of first metal bumps 41c, and the second connection electrode 37 and the second electrode pad 12 are joined and electrically connected by a plurality of second metal bumps 42c.

[0030] By using multiple first metal bumps 41c and second metal bumps 42c to bond the vibration element 3 to the substrate 10, the bonding strength between the vibration element 3 and the substrate 10 can be further improved compared to the case where only one first metal bump 41c and one second metal bump 42c are used.

[0031] Furthermore, by arranging a plurality of first metal bumps 41c and second metal bumps 42c in a line along the long side direction of the vibration element 3, the interval between the vibration element 3 and the substrate 10 after bonding can be made more uniform. Note that, although four first metal bumps 41c and four second metal bumps 42c are arranged in this embodiment, the present invention is not limited to this, and the number of first metal bumps 41c and second metal bumps 42c may be any number as long as it is two or more.

[0032] By adopting such a configuration, the bonding strength between the vibration element 3 and the substrate 10 can be improved, and the distance between the vibration element 3 and the substrate 10 can be made more uniform, and further, the same effects as those of the first embodiment can be obtained.

[0033] 5. Fifth embodiment Next, a vibration device 1d according to a fifth embodiment will be described with reference to Fig. 8 and Fig. 9. In Fig. 8, for the sake of convenience in describing the internal configuration of the vibration device 1d, a state in which the lid 20 is removed is illustrated.

[0034] The resonator device 1d of this embodiment is similar to the resonator device 1 of the first embodiment, except that the structure of the resonator substrate 30d is different from that of the resonator device 1 of the first embodiment. Note that the following description will focus on the differences from the first embodiment, and descriptions of the similar points will be omitted.

[0035] As shown in Figures 8 and 9, in the vibration device 1d, a through hole 38 that penetrates from the first surface 31 to the second surface 32 is arranged on the vibration substrate 30d of the vibration element 3d between the excitation electrode 33 and the first connection electrode 36 and the second connection electrode 37 in a planar view.

[0036] By providing the through holes 38, it is possible to prevent the non-conductive resin 40 from wetting and spreading into the vibration region where the excitation electrodes 33 are provided. In addition, the transmission of distortion generated by bonding the vibration element 3 to the substrate 10 and stress associated with temperature changes to the vibration region of the vibration element 3 can be reduced, and the transmission of vibration energy generated in the vibration region of the vibration element 3 to the bonded portion can be reduced, thereby improving the vibration characteristics of the vibration element 3.

[0037] With this configuration, it is possible to suppress the non-conductive resin 40 from spreading over the vibration region, and it is also possible to improve the vibration characteristics of the vibration element 3, and further to obtain the same effects as the first embodiment.

[0038] 6. Sixth embodiment Next, a vibration device 1e according to a sixth embodiment will be described with reference to Fig. 10. In Fig. 10, for the sake of convenience in describing the internal configuration of the vibration device 1e, a state in which the lid 20 is removed is illustrated.

[0039] The resonator device 1e of this embodiment is similar to the resonator device 1 of the first embodiment, except that the joining position between the resonator element 3e and the substrate 10e is different from that of the resonator device 1 of the first embodiment. Note that the following description will focus on the differences from the first embodiment, and descriptions of similar matters will be omitted.

[0040] As shown in FIG. 10, in the resonator device 1e, the first metal bump 41, the second metal bump 42, and the non-conductive resin 40 are arranged on one end side in the short side direction of the resonator element 3e in accordance with the arrangement positions of the first electrode pad 11e and the second electrode pad 12e provided on the substrate 10e. Specifically, they are arranged on the end on the negative Y side of the resonator element 3e. Therefore, the lengths along the short side direction of the first connection electrode 36e and the second connection electrode 37e provided on the first surface 31 are different, and the first connection electrode 36e is longer than the second connection electrode 37e. In this embodiment, the first metal bump 41, the second metal bump 42, and the non-conductive resin 40 are arranged on the end on the negative Y side of the resonator element 3e, but this is not limited thereto, and the first metal bump 41, the second metal bump 42, and the non-conductive resin 40 may be arranged on the end on the positive Y side of the resonator element 3e.

[0041] Furthermore, compared to a case where the first metal bump 41, the second metal bump 42, and the non-conductive resin 40 are disposed at the center in the short side direction of the vibration element 3e, the first metal bump 41, the second metal bump 42, and the non-conductive resin 40 are located farther from the vibration region of the vibration element 3e. Therefore, it is possible to further reduce the influence of distortion caused by bonding the vibration element 3e to the substrate 10e and stress caused by temperature change.

[0042] With this configuration, the metal bumps 41, 42 and the non-conductive resin 40 can be arranged in accordance with the positions of the electrode pads 11e, 12e of the substrate 10e, and the distance between the non-conductive resin 40 and the metal bumps 41, 42 and the vibration region of the vibration element 3e is increased, thereby further reducing the effects of distortion caused by bonding the vibration element 3e to the substrate 10e and stress due to temperature changes, and further providing effects equivalent to those of the first embodiment. [Explanation of symbols]

[0043] 1, 1a, 1b, 1c, 1d, 1e...vibration device, 3...vibration element, 10...substrate, 11...first electrode pad, 12...second electrode pad, 13...third surface, 14...fourth surface, 15...external terminal, 20...lid, 21...recess, 22...accommodation space, 25...joint member, 30...vibration substrate, 31...first surface, 32...second surface, 33...excitation electrode, 34...lead electrode, 35...side electrode, 36...first connection electrode, 37...second connection electrode, 38...through hole, 40...non-conductive resin, 41...first metal bump, 42...second metal bump, D...distance, L1, L2, L3...length.

Claims

1. a vibration element having an excitation electrode, a first surface on which a first connection electrode and a second connection electrode connected to the excitation electrode are arranged, and a second surface which is in a front-back relationship with the first surface; a substrate having a third surface facing the first surface of the vibration element and on which a first electrode pad and a second electrode pad are arranged; a first metal bump that joins and electrically connects the first connection electrode and the first electrode pad; a second metal bump that joins and electrically connects the second connection electrode and the second electrode pad; a non-conductive resin that overlaps at least a portion of a region including the first metal bump and the second metal bump in a plan view and bonds the vibration element and the substrate; Including, The length of the vibration element along the direction in which the first metal bump and the second metal bump are arranged is L1, The length of the first metal bump along the direction is L2. The length of the second metal bump along the direction is L3. When the distance between the outer edge of the first metal bump on the opposite side to the second metal bump side and the outer edge of the second metal bump on the opposite side to the first metal bump side is D, L2+L3<D≦L1 / 2 is satisfied. Vibration devices.

2. the non-conductive resin is a non-conductive adhesive, the non-conductive resin is disposed across from the second surface of the vibration element to the third surface of the substrate. The vibration device according to claim 1 .

3. the non-conductive resin is an underfill, the non-conductive resin is disposed between the first surface of the vibration element and the third surface of the substrate. The vibration device according to claim 1 .

4. moreover, a plurality of other first metal bumps that join and electrically connect the first connection electrode and the first electrode pad; a plurality of other second metal bumps that join and electrically connect the second connection electrode and the second electrode pad; Including, A vibration device according to any one of claims 1 to 3.

5. In the vibration element, a through hole is arranged between the excitation electrode and the first connection electrode and between the excitation electrode and the second connection electrode in a plan view. A vibration device according to any one of claims 1 to 3.

6. The vibration element has a rectangular shape in a plan view, the first metal bump, the second metal bump, and the non-conductive resin are disposed at a center portion in a short side direction of the rectangle; A vibration device according to any one of claims 1 to 3.

7. The vibration element has a rectangular shape in a plan view, the first metal bump, the second metal bump, and the non-conductive resin are arranged on one end side in a short side direction of the rectangle; A vibration device according to any one of claims 1 to 3.

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