Vibrating element

Abstract

To provide a vibrating element in which a damage due to an impact or the like can be suppressed.SOLUTION: A vibrating element includes: a vibrating substrate having a plate shape with a first surface and a second surface in a front and back relation and including a vibrating part and a supporting part that supports the vibrating part and is thinner than the vibrating part; an electrode including a first excitation electrode disposed on the first surface of the vibrating part, a second excitation electrode disposed on the second surface of the vibrating part, a first pad electrode disposed on the supporting part and electrically connected to the first excitation electrode, and a second pad electrode disposed on the supporting part and electrically connected to the second excitation electrode; a first metal film disposed in an upper layer of the first pad electrode and being thicker than the first pad electrode; and a second metal film disposed in an upper layer of the second pad electrode and being thicker than the second pad electrode.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] The vibration element described in Patent Document 1 has a vibration substrate and an electrode arranged on the vibration substrate. The vibration substrate also has a vibration part and a support part located around the vibration part, and the support part is thinner than the vibration part. Such a vibration element is fixed to a fixing object such as a package at the support part. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-123881 A Summary of the Invention [Problem to be solved by the invention]

[0004] In such a vibration element of Patent Document 1, the support part is thinner than the vibration part and is fixed to the fixed object at the support part, so that the vibration element is easily deformed by external impact, etc., which may reduce the vibration characteristics and the reliability of the electrical connection. [Means for solving the problem]

[0005] The vibration element of the present invention includes a vibration substrate having a plate shape with a first surface and a second surface which are in a front-back relationship, a vibration portion, and a support portion which supports the vibration portion and has a thickness smaller than that of the vibration portion; an electrode having a first excitation electrode arranged on the first surface of the vibration section, a second excitation electrode arranged on the second surface of the vibration section, a first pad electrode arranged on the support section and electrically connected to the first excitation electrode, and a second pad electrode arranged on the support section and electrically connected to the second excitation electrode; a first metal film disposed on an upper layer of the first pad electrode and having a thickness greater than that of the first pad electrode; The second pad electrode has a second metal film disposed in an upper layer thereof and having a thickness greater than that of the second pad electrode. [Brief description of the drawings]

[0006] [Figure 1] 1 is a cross-sectional view showing a vibrator according to a first embodiment of the present invention. [Diagram 2] 2 is a top view showing a vibration element of the vibrator of FIG. 1. [Diagram 3] FIG. [Figure 4] 3 is a cross-sectional view taken along line AA in FIG. 2. [Diagram 5] FIG. 3 is a cross-sectional view taken along line BB in FIG. [Figure 6] FIG. 4 is a top view of the vibration element with the metal film not shown. [Figure 7] FIG. 13 is a top view showing a modified example of the vibration element. [Figure 8] FIG. 13 is a top view showing a modified example of the vibration element. [Figure 9] FIG. 13 is a top view showing a modified example of the vibration element. [Figure 10] 5A to 5C are cross-sectional views illustrating a method for manufacturing the vibration element. [Figure 11] 5A to 5C are cross-sectional views illustrating a method for manufacturing the vibration element. [Figure 12] 5A to 5C are cross-sectional views illustrating a method for manufacturing the vibration element. [Figure 13] 5A to 5C are cross-sectional views illustrating a method for manufacturing the vibration element. [Figure 14] 5A to 5C are cross-sectional views illustrating a method for manufacturing the vibration element. [Figure 15] 5A to 5C are cross-sectional views illustrating a method for manufacturing the vibration element. [Figure 16] FIG. 4 is a cross-sectional view showing a vibration element according to a second embodiment of the present invention. [Figure 17] FIG. 4 is a cross-sectional view showing a vibration element according to a second embodiment of the present invention. [Figure 18]FIG. 4 is a cross-sectional view showing a vibration element according to a third embodiment of the present invention. [Figure 19] FIG. 4 is a cross-sectional view showing a vibration element according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vibration element of the present invention will be described in detail based on embodiments shown in the accompanying drawings.

[0008] First Embodiment FIG. 1 is a cross-sectional view showing a vibrator according to a first embodiment of the present invention. FIG. 2 is a top view showing a vibration element included in the vibrator of FIG. 1. FIG. 3 is a perspective view of the vibration element. FIG. 4 is a cross-sectional view taken along line AA in FIG. 2. FIG. 5 is a cross-sectional view taken along line BB in FIG. 2. FIG. 6 is a top view of the vibration element with the metal film omitted. FIGS. 7 to 9 are top views showing modified examples of the vibration element. FIGS. 10 to 15 are cross-sectional views for explaining a manufacturing method of the vibration element.

[0009] The vibrator 1 shown in FIG. 1 has a package 2 and a vibrating element 3 housed in the package 2.

[0010] The package 2 also has a base 21 and a lid 22. The base 21 is box-shaped and has a recess 211 that opens on its upper surface. The vibration element 3 is mounted on the bottom surface of the recess 211 by bonding members B1 and B2. On the other hand, the lid 22 is plate-shaped and is bonded to the upper surface of the base 21 via a sealing member 23 such as a seal ring or low-melting glass so as to close the opening of the recess 211. This makes the recess 211 airtightly sealed, and a storage space S is formed in the package 2. The storage space S is airtight and in a reduced pressure state, preferably a vacuum or a state close to it. This reduces viscous resistance and improves the oscillation characteristics of the vibration element 3.

[0011] There are no particular limitations on the materials that make up the base 21 and the lid 22. For example, the base 21 can be made of various ceramic materials such as alumina and titania, and the lid 22 can be made of various metal materials such as kovar. This reduces the difference in linear expansion coefficient between the base 21 and the lid 22, resulting in a package 2 that is less susceptible to thermal stress.

[0012] Further, a pair of internal terminals 241, 242 are arranged on the bottom surface of the recess 211, and a pair of external terminals 251, 252 are arranged on the lower surface of the base 21. The internal terminal 241 is electrically connected to the external terminal 251 via an internal wiring (not shown) formed in the base 21. Similarly, the internal terminal 242 is electrically connected to the external terminal 252 via the internal wiring. Further, the internal terminal 241 is electrically connected to the vibration element 3 via a conductive bonding member B1, and the internal terminal 242 is electrically connected to the vibration element 3 via a conductive bonding member B2.

[0013] The bonding members B1 and B2 are not particularly limited as long as they have both electrical conductivity and adhesiveness, and may be, for example, various metal bumps such as gold bumps, silver bumps, copper bumps, solder bumps, various conductive pastes such as silver paste and copper paste, conductive adhesives in which conductive fillers such as silver fillers are dispersed in various adhesives such as polyimide, epoxy, silicone, and acrylic. When the former metal bumps are used as the bonding members B1 and B2, gas generation from the bonding members B1 and B2 can be suppressed, and environmental changes in the storage space S, particularly pressure increases, can be effectively suppressed. In addition, since the bonding members B1 and B2 do not wet and spread, the bonding members B1 and B2 can be arranged at a narrow pitch, and the vibrator 1 can be made smaller. On the other hand, when the latter conductive adhesive is used as the bonding members B1 and B2, the bonding members B1 and B2 become softer than the metal bumps, and stress is less likely to be transmitted to the vibration element 3.

[0014] As shown in Fig. 2 and Fig. 3, the vibration element 3 has a vibration substrate 4 which is an AT-cut quartz substrate, and an electrode layer 5 and a metal film 6 arranged on the vibration substrate 4. The AT-cut quartz substrate has a thickness-shear vibration mode and has a third-order frequency-temperature characteristic. Therefore, the vibration element 3 has excellent temperature characteristics. However, the cut angle of the vibration substrate 4 is not particularly limited.

[0015] To briefly explain the AT-cut quartz substrate, the quartz substrate has X-axis, Y-axis, and Z-axis, which are crystal axes perpendicular to each other. The X-axis, Y-axis, and Z-axis are called the electrical axis, mechanical axis, and optical axis, respectively. The AT-cut quartz substrate is a "rotated Y-cut quartz substrate" cut along a plane obtained by rotating the XZ plane around the X-axis by a certain angle θ, and a substrate cut along a plane rotated θ=35°15' is called an "AT-cut quartz substrate". In the following, the Y-axis and Z-axis rotated around the X-axis corresponding to the angle θ are called the Y'-axis and Z'-axis. In other words, the quartz substrate has a thickness in the Y'-axis direction and a spread in the X-Z'-plane direction. In the following, the arrow tip side of each axis is also called the "plus side", and the opposite side is also called the "minus side".

[0016] The vibration substrate 4 is plate-shaped and has an upper surface 4a as a first surface and a lower surface 4b as a second surface, which are in a front-back relationship. The vibration substrate 4 is rectangular in plan view, particularly a rectangle with the X-axis direction as its longitudinal direction. However, the shape of the vibration substrate 4 in plan view is not particularly limited. The vibration substrate 4 has a vibration section 41 and a support section 42 that supports the vibration section 41. The support section 42 is located on the negative side of the vibration section 41 in the X-axis direction. As shown in FIG. 2, the vibration element 3 is fixed to the base 21 at the support section 42 via bonding members B1 and B2.

[0017] In this embodiment, the vibrating portion 41 has a uniform thickness over its entirety, but is not limited to this and may be of a so-called "mesa type" or "inverted mesa type."

[0018] Further, the support portion 42 is thinner than the vibrating portion 41. That is, as shown in FIGS. 4 and 5, when the thickness of the vibrating portion 41 is t1 and the thickness of the support portion 42 is t2, t2 < t1. Thereby, the support portion 42 is more likely to deform, and the stress applied from the base 21, particularly the thermal stress caused by the difference in the linear expansion coefficients between the base 21 and the vibrating substrate 4, can be effectively absorbed and relaxed. Therefore, it is difficult for stress to be transmitted to the vibrating portion 41, and fluctuations in the vibration characteristics can be effectively suppressed. Thus, the vibrating element 3 having excellent vibration characteristics is obtained.

[0019] t1 is not particularly limited and varies depending on the frequency of the vibrating element 3. For example, it can be set to about 30 μm or more and 100 μm or less. Also, t2 is not particularly limited and varies depending on the dimensions of the vibrating portion 41 and the like. For example, it is preferably set to about 5 μm or more and 15 μm, and more preferably about 10 μm. Thereby, the support portion 42 becomes sufficiently soft, and the stress from the base 21 can be more effectively absorbed and relaxed.

[0020] Further, the support portion 42 is formed to be recessed on both the upper and lower sides. That is, the upper surface 4a of the support portion 42 is located below the upper surface 4a of the vibrating portion 41, and the lower surface 4b of the support portion 42 is located above the lower surface 4b of the vibrating portion 41. And the thickness center of the vibrating portion 41 and the thickness center of the support portion 42 are located on the same X-Z' plane. Therefore, the vibrating substrate 4 has an axially symmetric shape. Thereby, the vibrating element 3 can be mounted on the base 21 in either the upper or lower direction, facilitating the manufacture of the vibrator 1.

[0021] Further, as shown in FIG. 6, the support portion 42 is divided into two, and has a first support portion 421 and a second support portion 422 that are arranged side by side in the Z' axis direction and spaced apart from each other. The first and second support portions 421 and 422 are symmetrically arranged with respect to the center line extending in the X axis direction passing through the center of the vibrating portion 41.

[0022] Further, the first support portion 421 has a first base portion 421a and a first connecting portion 421b positioned between the first base portion 421a and the vibrating portion 41 and connecting them. Similarly, the second support portion 422 has a second base portion 422a and a second connecting portion 422b positioned between the second base portion 422a and the vibrating portion 41 and connecting them. And the first base portion 421a is joined to the joining member B1, and the second base portion 422a is joined to the joining member B2. According to such a configuration, by deforming the support portion 42 so that the first and second support portions 421 and 422 are separated or approximated, the stress applied from the base 21 can be more effectively absorbed and relaxed. Therefore, it becomes difficult for the stress from the base 21 to be transmitted by the vibrating portion 41, and fluctuations in vibration characteristics can be effectively suppressed. Thus, the vibrating element 3 having excellent vibration characteristics is obtained.

[0023] Here, the width W1b of the first connecting portion 421b is smaller than the width W1a of the first base portion 421a. That is, W1b < W1a. Similarly, the width W2b of the second connecting portion 422b is smaller than the width W2a of the second base portion 422a. That is, W2b < W2a. Thereby, the root portions of the first support portion 421 and the second support portion 422 are softened respectively, and the first support portion 421 and the second support portion 422 are more easily deformed respectively. Therefore, the support portion 42 is more easily deformed, and the stress applied from the base 21 can be more effectively absorbed and relaxed. Therefore, it becomes difficult for the stress from the base 21 to be transmitted by the vibrating portion 41, and fluctuations in vibration characteristics can be effectively suppressed.

[0024] 6, the electrode layer 5 includes a first excitation electrode 511 arranged on the upper surface 4a of the vibrating section 41, a second excitation electrode 521 arranged on the lower surface 4b of the vibrating section 41 so as to face the first excitation electrode 511, a first pad electrode 512 arranged on the first support section 421, a second pad electrode 522 arranged on the second support section 422, a first connection electrode 513 electrically connecting the first excitation electrode 511 and the first pad electrode 512, and a second connection electrode 523 electrically connecting the second excitation electrode 521 and the second pad electrode 522. The first pad electrode 512 is electrically connected to the internal terminal 241 via the bonding member B1, and the second pad electrode 522 is electrically connected to the internal terminal 242 via the bonding member B2. This electrically connects the package 2 and the vibrating element 3.

[0025] Moreover, the first pad electrode 512 is formed on the entire surface of the first support portion 421, and the second pad electrode 522 is formed on the entire surface of the second support portion 422. However, the arrangement of the first and second pad electrodes 512, 522 is not particularly limited.

[0026] Such an electrode layer 5 is formed by patterning a metal film formed on the surface of the vibration substrate 4 using photolithography and etching techniques. The configuration of the electrode layer 5 is not particularly limited as long as it has conductivity, but can be, for example, a laminate of a Cr (chromium) underlayer and a Au (gold) surface layer. The thickness of the electrode layer 5 is not particularly limited, but is about 3000 Å.

[0027] As described above, in the vibration element 3, the supporting portion 42 is made thinner than the vibration portion 41 to absorb and reduce the stress applied from the base 21, but the mechanical strength is accordingly reduced, and there is a risk of breakage due to impact. Therefore, the vibration element 3 further has a metal film 6 for reinforcing the supporting portion 42.

[0028] 2 to 5, the metal film 6 has a first metal film 61 disposed on the first pad electrode 512 and reinforcing the first support portion 421, and a second metal film 62 disposed on the second pad electrode 522 and reinforcing the second support portion 422. This increases the strength of the support portion 42, and can improve the impact resistance of the vibration element 3. Note that by making the support portion 42 thin and compensating for the insufficient strength with the first and second metal films 61 and 62, the toughness of the support portion 42 is increased, and it is possible to achieve a good balance between absorbing and mitigating stress and ensuring mechanical strength.

[0029] In this embodiment, the metal film 6 is disposed directly on the first and second pad electrodes 512, 522, but is not limited to this. In other words, the metal film 6 may be disposed between the first and second pad electrodes 512, 522 and another metal layer. In other words, it is sufficient that the metal film 6 is disposed in an upper layer above the first and second pad electrodes 512, 522.

[0030] Moreover, the first metal film 61 covers the entire surface of the first support portion 421. This makes it possible to more effectively reinforce the first support portion 421. Furthermore, the first metal film 61 is disposed across the first support portion 421 and the vibrating portion 41. This makes it possible for the boundary portion between the first support portion 421 and the vibrating portion 41, which is a portion where stress is likely to concentrate, to be covered with the first metal film 61, improving the mechanical strength of that portion.

[0031] Moreover, the second metal film 62 covers the entire surface of the second support portion 422. This makes it possible to more effectively reinforce the second support portion 422. Furthermore, the second metal film 62 is disposed across the second support portion 422 and the vibrating portion 41. This makes it possible for the boundary portion between the second support portion 422 and the vibrating portion 41, which is a portion where stress is likely to concentrate, to be covered with the second metal film 62, improving the mechanical strength of that portion.

[0032] The thickness t6 of the first and second metal films 61, 62 is larger than the thickness t5 of the electrode layer 5. That is, t6>t5. The thicknesses t6, t5 refer to average thicknesses. This allows the first and second metal films 61, 62 to effectively reinforce the support portion 42. The thickness t6 is not particularly limited and varies depending on the dimensions of the vibration substrate 4, but is preferably, for example, 5 μm or more and 50 μm or less. This makes the first and second metal films 61, 62 sufficiently thick, and the reinforcing effect of the vibration substrate 4 becomes more noticeable.

[0033] The first and second metal films 61, 62 are not particularly limited to a specific material, but in this embodiment, they are made of nickel (Ni). This provides the first and second metal films 61, 62 with high strength. Furthermore, by using a plating method, the first and second metal films 61, 62 can be easily formed to be thick.

[0034] At least one through hole 611 is formed in the first metal film 61 located on the upper surface 4a and the lower surface 4b of the first base portion 421a, and a first pad electrode 512 is exposed from the through hole 611. Similarly, at least one through hole 621 is formed in the second metal film 62 located on the upper surface 4a and the lower surface 4b of the second base portion 422a, and a second pad electrode 522 is exposed from the through hole 621.

[0035] Since the first metal film 61 has conductivity, by bonding the first metal film 61 to the bonding member B1, the first pad electrode 512 and the bonding member B1 can be electrically connected through the first metal film 61. However, there is a risk that the first metal film 61 cannot exhibit sufficient conductivity due to oxidation. Therefore, by exposing the first pad electrode 512 from the first metal film 61 and directly bonding the first pad electrode 512 and the bonding member B1 at that portion, they can be more reliably conducted regardless of the state of the first metal film 61. The shape, number, arrangement, etc. of the through holes 621 are not particularly limited. The same applies to the second metal film 62.

[0036] The configuration of the vibration element 3 has been described above. However, the configuration of the vibration element 3 is not particularly limited, and may be, for example, the configuration as shown in FIG. 7 to FIG. 9. Note that in FIG. 7 to FIG. 9, for convenience of explanation, the electrode layer 5 and the metal film 6 are omitted from illustration. For example, in this embodiment, the first connecting portion 421b in the first support portion 421 is arranged biased toward the outer edge side of the vibration substrate 4 with respect to the first base portion 421a, and the second connecting portion 422b in the second support portion 422 is arranged biased toward the outer edge side of the vibration substrate 4 with respect to the second base portion 422a. However, this is not limited thereto, and for example, as shown in FIG. 7, the first connecting portion 421b in the first support portion 421 may be arranged biased toward the inner side of the vibration substrate 4 with respect to the first base portion 421a, and the second connecting portion 422b in the second support portion 422 may be arranged biased toward the inner side of the vibration substrate 4 with respect to the second base portion 422a. Furthermore, as shown in FIGS. 8 and 9, a plurality of first and second connecting portions 421b, 422b may be formed and aligned in the Z'-axis direction.

[0037] Next, a manufacturing method of the vibration element 3 will be described. First, as shown in FIG. 10, an AT-cut quartz substrate 400, which is a base material of the vibration substrate 4, is prepared. The quartz substrate 400 is larger than the vibration substrate 4, and a plurality of vibration substrates 4 can be formed from the quartz substrate 400. Next, as shown in FIG. 11, the quartz substrate 400 is patterned using a photolithography technique and an etching technique to form the vibration substrate 4. Next, as shown in FIG. 12, an electrode layer 5 is formed on the vibration substrate 4. The electrode layer 5 can be formed by forming a metal film on the surface of the vibration substrate 4 and patterning the formed metal film using a photolithography technique and an etching technique. Next, as shown in FIG. 13, a mask M is formed on the vibration substrate 4, which opens the areas where the first and second metal films 61 and 62 are to be formed. Next, as shown in FIG. 14, a metal film 6 is formed on the surface of the vibration substrate 4 by electroless plating. Finally, as shown in FIG. 15, the mask M is removed. As a result, the vibration element 3 is obtained. According to such a manufacturing method, the vibration element 3 can be easily manufactured.

[0038] The above has described the vibrator 1. As described above, the vibrating element 3 included in such a vibrator 1 has a plate shape with an upper surface 4a as a first surface and a lower surface 4b as a second surface that are in a front-back relationship, and includes a vibrating substrate 4 having a vibrating portion 41 and a supporting portion 42 that supports the vibrating portion 41 and has a thickness smaller than that of the vibrating portion 41, a first excitation electrode 511 arranged on the upper surface 4a of the vibrating portion 41, a second excitation electrode 521 arranged on the lower surface 4b of the vibrating portion 41, an electrode layer 5 having a first pad electrode 512 arranged on the supporting portion 42 and electrically connected to the first excitation electrode 511 and a second pad electrode 522 electrically connected to the second excitation electrode 521, a first metal film 61 arranged on an upper layer of the first pad electrode 512 and thicker than the first pad electrode 512, and a second metal film 62 arranged on an upper layer of the second pad electrode 522 and thicker than the second pad electrode 522. With this configuration, the support portion 42 becomes easily deformable, and can effectively absorb and alleviate the stress applied from the base 21. Therefore, stress is less likely to be transmitted to the vibration portion 41, and fluctuations in vibration characteristics caused by stress can be effectively suppressed. This results in a vibration element 3 with excellent vibration characteristics. Furthermore, by arranging the first and second metal films 61, 62 on the support portion 42, the support portion 42 is reinforced, and the vibration element 3 has excellent impact resistance.

[0039] As described above, the first metal film 61 and the second metal film 62 are disposed across the vibration section 41 and the support section 42, respectively. This allows the boundary between the support section 42 and the vibration section 41, where stress is likely to concentrate, to be covered with the first and second metal films 61, 62, improving the mechanical strength of the relevant portion. This makes it possible to reinforce the vibration substrate 4 more effectively.

[0040] As described above, the support 42 has the first support 421 and the second support 422 spaced apart from each other, the first pad electrode 512 is disposed on the first support 421, and the second pad electrode 522 is disposed on the second support 422. With this configuration, the support 42 deforms so that the first and second support parts 421 and 422 move apart or closer to each other, thereby effectively absorbing and mitigating stress applied from the outside. This results in a vibration element 3 with excellent vibration characteristics.

[0041] As described above, the first support 421 has the first base 421a and the first connecting portion 421b that connects the first base 421a and the vibration portion 41 and is narrower than the first base 421a, and the second support 422 has the second base 422a and the second connecting portion 422b that connects the second base 422a and the vibration portion 41 and is narrower than the second base 422a. This makes the root portions of the first and second support portions 421 and 422 soft, making the first and second support portions 421 and 422 more easily deformable. Therefore, it is possible to more effectively absorb and alleviate stress applied from the outside. Therefore, the vibration element 3 has excellent vibration characteristics.

[0042] As described above, the first metal film 61 covers the entire surface of the first support portion 421, and the second metal film 62 covers the entire surface of the second support portion 422. This makes it possible to reinforce the first and second support portions 421 and 422 more effectively.

[0043] As described above, the first metal film 61 has a through hole 611 exposing the first pad electrode 512, and the second metal film 62 has a through hole 621 exposing the second pad electrode 522. This makes it possible to more reliably establish electrical continuity between the bonding members B1, B2 and the first and second pad electrodes 512, 522.

[0044] <Second embodiment> Fig. 16 and Fig. 17 are cross-sectional views showing a vibration element according to a second embodiment of the present invention, respectively. Fig. 16 is a cross-sectional view taken along line AA in Fig. 2, and Fig. 17 is a cross-sectional view taken along line BB in Fig. 2.

[0045] The vibration element 3 according to this embodiment is similar to the vibration element 3 according to the first embodiment, except that it further includes a third metal film 63 and a fourth metal film 64. In the following description, the vibration element 3 according to this embodiment will be described with a focus on the differences from the first embodiment, and the description of the same points will be omitted. In addition, in each drawing of this embodiment, the same reference numerals are used for the same configurations as those in the above-mentioned embodiment.

[0046] The vibration element 3 shown in FIG. 16 and FIG. 17 further includes a third metal film 63 disposed on the first metal film 61 and a fourth metal film 64 disposed on the second metal film 62. This makes it possible to more effectively reinforce the support portion 42. The third metal film 63 and the fourth metal film 64 are not particularly limited, but are made of Au (gold) in this embodiment. This makes it possible to suppress corrosion and oxidation of the first and second metal films 61 and 62. In addition, this has good compatibility with the gold bumps used as the bonding members B1 and B2, and allows the vibration element 3 to be bonded more firmly to the base 21.

[0047] In this embodiment, the third metal film 63 is disposed directly on the first metal film 61, and the fourth metal film 64 is disposed directly on the second metal film 62, but this is not limited to the above. That is, the third metal film 63 may be disposed on the first metal film 61 via another metal layer, and the fourth metal film 64 may be disposed on the second metal film 62 via another metal layer. In other words, it is sufficient that the third metal film 63 is disposed in an upper layer above the first metal film 61, and it is sufficient that the fourth metal film 64 is disposed in an upper layer above the second metal film 62.

[0048] As described above, the vibration element 3 of this embodiment has the third metal film 63 disposed on the upper layer of the first metal film 61, and the fourth metal film 64 disposed on the upper layer of the second metal film 62. This makes it possible to more effectively reinforce the support portion 42. In particular, by forming the third metal film 63 and the fourth metal film 64 from Au (gold), it is possible to suppress corrosion and oxidation of the first and second metal films 61 and 62. In addition, this has good compatibility with the gold bumps used as the bonding members B1 and B2, and the vibration element 3 can be bonded more firmly to the base 21.

[0049] The second embodiment as described above can also achieve the same effects as the first embodiment described above.

[0050] <Third embodiment> Fig. 18 and Fig. 19 are cross-sectional views showing a vibration element according to a third embodiment of the present invention, respectively. Fig. 18 is a cross-sectional view taken along line AA in Fig. 2, and Fig. 19 is a cross-sectional view taken along line BB in Fig. 2.

[0051] The vibration element 3 according to this embodiment is similar to the vibration element 3 according to the first embodiment described above, except that the shape of the vibration substrate 4 is different. In the following description, the vibration element 3 according to this embodiment will be described with a focus on the differences from the first embodiment described above, and a description of the similar points will be omitted. In addition, in each drawing of this embodiment, the same reference numerals are used for the same configurations as those in the above-mentioned embodiment.

[0052] The vibration element 3 shown in FIG. 18 and FIG. 19 is configured such that the lower surface 4b of the support portion 42 and the lower surface 4b of the vibration portion 41 are continuous flat surfaces. The first metal film 61 is disposed on the lower surface 4b of the first support portion 421, and the second metal film 62 is disposed on the lower surface 4b of the second support portion 422. In other words, the first and second metal films 61 and 62 are not disposed on the upper surface 4a or side surface of the support portion 42. With this configuration, the first and second metal films 61 and 62 can be formed before the outer shape of the vibration substrate 4 is formed. Therefore, the accuracy of forming the first and second metal films 61 and 62 is improved.

[0053] As described above, in the vibration element 3 of this embodiment, the lower surface 4b of the vibration portion 41 and the lower surface 4b of the support portion 42 are continuous flat surfaces, and the first metal film 61 and the second metal film 62 are disposed on the lower surface 4b side. This allows the first and second metal films 61, 62 to be formed before the outer shape of the vibration substrate 4 is formed. Therefore, the accuracy of forming the first and second metal films 61, 62 is improved.

[0054] The third embodiment as described above can also achieve the same effects as the first embodiment described above.

[0055] Although the vibration element of the present invention has been described above based on the illustrated embodiment, the present invention is not limited thereto, and the configuration of each part can be replaced with any configuration having a similar function. In addition, any other configuration may be added to the present invention. In addition, the present invention may be a combination of any two or more configurations of the above-mentioned embodiments.

[0056] In the above-described embodiment, the support portion 42 is divided into the first and second support portions 421 and 422, but this is not limited thereto. In other words, the first and second pad electrodes 512 and 522 may be disposed together on one support portion 42.

[0057] In addition, in the above-described embodiment, the vibration element 3 is applied to the vibrator 1, but this is not limited to this, and it can also be applied to an oscillator in which an oscillation circuit that oscillates the vibration element 3 is implemented within the package 2. [Explanation of symbols]

[0058] 1...vibrator, 2...package, 21...base, 211...recess, 22...lid, 23...sealing member, 241...internal terminal, 242...internal terminal, 251...external terminal, 252...external terminal, 3...vibration element, 4...vibration substrate, 4a...upper surface, 4b...lower surface, 400...quartz substrate, 41...vibration portion, 42...support portion, 421...first support portion, 421a...first base portion, 421b...first connection portion, 422...second support portion, 422a...second base portion, 422b...second connection portion, 5...electrode layer, 511...first Excitation electrode, 512...first pad electrode, 513...first connection electrode, 521...second excitation electrode, 522...second pad electrode, 523...second connection electrode, 6...metal film, 61...first metal film, 611...through hole, 62...second metal film, 621...through hole, 63...third metal film, 64...fourth metal film, B1...joining member, B2...joining member, M...mask, S...accommodation space, t1...thickness, t2...thickness, t3...thickness, t5...thickness, t6...thickness, W1a...width, W1b...width, W2a...width, W2b...width

Claims

1. a plate-like vibration section having a first surface and a second surface that are opposite surfaces to each other; a vibration substrate having a support portion that supports the vibration portion and has a thickness smaller than that of the vibration portion; a first excitation electrode disposed on the first surface of the vibration part; a second excitation electrode disposed on the support portion and electrically connected to the first excitation electrode; a first pad electrode disposed on the support portion and electrically connected to the second excitation electrode; a second pad electrode; A first gold layer is disposed on the upper layer of the first pad electrode and has a thickness greater than that of the first pad electrode. Genus membrane and A second gold layer is disposed on the second pad electrode and has a thickness greater than that of the second pad electrode. A vibration element comprising: a metal film;

2. The first metal film and the second metal film each extend across the vibration section and the support section. The vibration element according to claim 1 , wherein the first and second electrodes are arranged in a direction perpendicular to the surface of the vibration element.

3. the support portion includes a first support portion and a second support portion that are spaced apart from each other; the first pad electrode is disposed on the first support portion; The vibration element according to claim 1 , wherein the second pad electrode is disposed on the second support portion.

4. The first support portion connects the first base portion and the vibration portion, and the first base portion a first connecting portion having a width narrower than The second support portion connects the second base portion and the vibration portion, and the second base portion The vibration element according to claim 3 , further comprising: a second connecting portion having a width narrower than the first connecting portion.

5. the first metal film covers the entire surface of the first support portion, The vibration element according to claim 3 , wherein the second metal film covers the entire surface of the second support portion. 。

6. the first metal film has a through hole exposing the first pad electrode; The second metal film according to claim 3 , wherein the second metal film has a through hole exposing the second pad electrode. Vibration element.

7. the second surface of the vibration portion and the second surface of the support portion are continuous flat surfaces, The first metal film and the second metal film are disposed on the second surface side of the support portion. The vibration element according to claim 1.

8. a third metal film disposed on an upper layer of the first metal film; a fourth metal film disposed on an upper layer of the second metal film, element. ？

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