JP2023079859A - Crystal vibration element and crystal vibration device - Google Patents

Abstract

To provide a crystal vibration element and a crystal vibration device capable of suppressing fluctuations in vibration characteristics and achieving miniaturization.SOLUTION: A crystal vibration element includes a vibrating portion 11, a frame portion 12 provided at a predetermined distance from the outer periphery of the vibrating portion 11, and connecting portions 13 and 14 made of metal films having a predetermined width and thickness, and first and second excitation electrodes 111 and 112 of the vibrating portion 11 and electrodes 121 and 122 of the frame portion 12 are electrically connected via the connecting portions 13 and 14, and the vibrating portion 11 is held by the frame portion 12 using the connecting portions 13 and 14.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a crystal oscillator element and a crystal oscillator device.

Conventionally, in a crystal oscillator device, the oscillation region of the crystal oscillator is electromechanically connected to the package via a conductive adhesive or through a crystal connecting portion provided in the crystal oscillator. (See Patent Document 1, for example). In such a configuration, when an external force acts on the package, there is a problem that stress is likely to be transmitted to the vibration region and the vibration characteristics are likely to fluctuate.

Therefore, a crystal resonator element has been proposed in which a vibration region (vibrating portion) is held by a frame portion using a plurality of wires (see Patent Documents 2 and 3, for example). With this configuration, it is possible to prevent external vibrations and impacts from being directly transmitted to the vibrating section, and to suppress sudden fluctuations in vibration characteristics.

JP 2010-252051 A JP 2012-4625 A JP 2019-47373 A

However, in the configuration using wires as described above, there is a possibility that the vibration characteristics may fluctuate due to the influence of stress (pulling each other) due to a plurality of wire bridges. Moreover, since it is necessary to secure a formation area for the wire connection pads, it is feared that miniaturization will become difficult.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described circumstances, and provides a crystal oscillator element and a crystal oscillator device that are capable of suppressing fluctuations in oscillation characteristics and that can be miniaturized. for the purpose.

The present invention constitutes means for solving the above-described problems as follows. That is, the present invention provides a crystal oscillator, comprising: a vibrating portion; a frame portion provided at a predetermined distance from the outer periphery of the vibrating portion; the electrode of the vibrating portion and the electrode of the frame portion are electrically connected via the connecting portion, and the vibrating portion is held by the frame portion by the connecting portion. It is characterized by

According to the above configuration, since a space is formed between the vibrating portion and the frame portion, and the vibrating portion is separated from the frame portion, environmental stress due to heat acting on the vibrating portion and external force can be reduced. and suppress fluctuations in vibration characteristics. In addition, compared to a configuration in which a plurality of wires are used to support the vibrating portion, the vibrating portion is not affected by the stress caused by the mutual pulling of the wires, so fluctuations in vibration characteristics can be suppressed. Furthermore, since it is not necessary to secure a formation area for the wire connection pads in the vibrating portion and the frame portion, the size can be reduced.

In the above configuration, it is preferable that the frame portion has at least three sides. According to this configuration, by holding the vibrating portion by at least three sides of the frame portion, it is possible to ensure the stability of holding of the vibrating portion by the connecting portion.

In the above configuration, it is preferable that the vibrating portion has a rectangular shape in a plan view, and the connecting portion is formed on at least a pair of opposing sides of the vibrating portion. With this configuration, the vibrating section is less likely to tilt or rotate with respect to the frame, and the stability of holding the vibrating section by the connecting section can be enhanced.

In the above configuration, it is preferable that the vibrating portion is rectangular in plan view, and that at least one connecting portion is formed on each side of the vibrating portion. According to this configuration, it is possible to stabilize the holding of the vibrating portion by the connecting portion.

In the above configuration, it is preferable that a plurality of the connecting portions are formed with respect to one side of the vibrating portion and each connecting portion has a different width and/or thickness. According to this configuration, when the width and thickness of the outer connecting portion are large and the width and thickness of the inner connecting portion are small, the stress acting on the inner connecting portion can be easily released, and the shock resistance of the vibrating portion can be improved. Since it improves, it can suppress that a connection part fracture|ruptures.

In the above configuration, three or more connecting portions are formed for one side of the vibrating portion, and the width and/or thickness of the connecting portion on the outer side is greater than the width and/or thickness of the connecting portion on the central side in plan view. and/or the thickness is preferably greater. According to this configuration, since the width and thickness of the outer connecting portion are large and the width and thickness of the inner connecting portion are small, the stress acting on the inner connecting portion can be easily released, and the shock resistance of the vibrating portion can be improved. Therefore, breakage of the connecting portion can be suppressed.

In the above configuration, it is preferable that the connecting portion includes at least an Au film. According to this configuration, due to the ductility and malleability of Au, the holding strength of the vibrating portion by the connecting portion is less likely to decrease, and the environmental change and secular change of the connecting portion can be suppressed.

In the above configuration, it is preferable that the connection portion with the vibrating portion and the connection portion with the frame portion in the connection portion have a structure in which an Au film is laminated on a Cr film or a Ti film. According to this configuration, since Cr or Ti has good adhesion to crystal, it is possible to improve the bonding strength between the connecting portion and the vibrating portion and the bonding strength between the connecting portion and the frame portion.

In the above configuration, the frame portion is rectangular in plan view, and the vibration portion is held by connecting the connecting portions at diagonal positions of corners of the inner circumference of the frame portion. preferably. According to this configuration, since the corners of the inner circumference of the frame, which are portions having a large rotational moment with respect to the center of the vibrating portion, are held by the connecting portions, the rotating motion of the vibrating portion is suppressed. As a result, the stability of holding the vibrating portion by the connecting portion can be improved.

In the above configuration, the vibrating portion has a rectangular shape in plan view, the connecting portion is formed only on the long side on one main surface of the vibrating portion, and the short side is formed on the other main surface of the vibrating portion. It is preferable that the connecting portion is formed only on the sides. According to this configuration, no connecting portion is formed on the short side of the vibrating portion on one main surface, and no connecting portion is formed on the long side of the vibrating portion on the other main surface. When the outer shape of the vibrating portion is processed by wet etching, the etching process can be performed with high accuracy.

In the above configuration, it is preferable that the coupling portion is provided with a buffer portion. According to this configuration, the connecting portion can be elastically expanded and contracted, and the impact resistance of the vibrating portion can be improved.

In the above configuration, it is preferable that the connecting portion is also provided on a side wall of the frame portion and/or a side wall of the vibrating portion. According to this configuration, it is possible to improve the joint strength between the connecting portion and the frame portion and/or the vibrating portion, and it is possible to suppress breakage of the connecting portion even when an external impact is applied.

In the above configuration, the vibrating portion is rectangular in plan view, and the connecting portion has a structure in which a metal film is formed over the entire circumference of each of the inner peripheral portion of the frame portion and the outer peripheral portion of the vibrating portion. It is preferable that the connecting portion bridges the frame portion and the vibrating portion. According to this configuration, even if a portion of the connecting portion is broken when an external impact is applied, electrical connection can be ensured by the metal film formed over substantially the entire circumference, thereby improving reliability. can be enhanced.

In the above configuration, it is preferable that a wide metal film is bridged on both the frame portion and the vibrating portion, and the connecting portion is formed by providing a plurality of openings in the metal film. According to this configuration, the stress acting on the connecting portion can be relieved by the connecting portion provided with the plurality of openings.

In the above configuration, it is preferable that a thin portion having substantially the same thickness as the vibrating portion and thinner than the frame portion is provided on the vibrating portion side of the frame portion. According to this configuration, there is no height difference between the thin portion and the vibrating portion, and unnecessary tension is less likely to act on the connecting portion, so that stable electrical connection can be secured and reliability can be improved. can.

Further, the present invention is a crystal oscillation device, wherein the crystal oscillation element configured as described above is hermetically sealed by an upper sealing member and a lower sealing member. According to this configuration, the same effect as that of the crystal oscillator having the above configuration can be obtained in the crystal oscillator device having the crystal oscillator having the above configuration.

In the above configuration, it is preferable that the upper sealing member and the lower sealing member each have a concave portion formed on the crystal vibrating element side, and that the vibrating portion be opposed to the bottom surface of each concave portion. With this configuration, it is possible to secure a movable area for the vibrating section, and even if the vibrating section slightly moves due to an external impact or the like, contact with the upper sealing member or the lower sealing member is suppressed. can.

In the above configuration, it is preferable that a convex portion is formed on the bottom surface of each concave portion at a position facing the vibrating portion. According to this configuration, each concave portion secures a movable region for the region where the excitation electrode of the vibrating portion is formed due to an external impact or the like, and the region where the excitation electrode of the vibrating portion is not formed on the bottom surface of each concave portion. By providing the convex portion at the position facing the , it is possible to suppress the amount of displacement of the vibrating portion in the vertical direction. As a result, breakage of the connecting portion can be suppressed.

According to the present invention, fluctuations in vibration characteristics can be suppressed, and moreover, miniaturization can be achieved.

1 is an exploded perspective view showing a schematic configuration of a crystal oscillator according to this embodiment; FIG. FIG. 2 is a perspective view showing a second main surface side of a crystal diaphragm of the crystal oscillator of FIG. 1; 2 is a cross-sectional view taken along line A1-A1 of FIG. 1; FIG. FIG. 10 is a perspective view showing the first main surface side of the crystal diaphragm according to Modification 1; FIG. 5 is a perspective view showing the second main surface side of the crystal diaphragm of FIG. 4 ; FIG. 11 is a plan view showing the first main surface side of a quartz diaphragm according to Modification 2; FIG. 11 is a plan view showing the first main surface side of a crystal diaphragm according to Modification 3; FIG. 11 is a cross-sectional view showing a connecting portion of a crystal diaphragm according to Modification 4; FIG. 11 is a cross-sectional view showing a connecting portion of a crystal diaphragm according to Modification 5; FIG. 11 is a plan view showing the first main surface side of a crystal diaphragm according to Modification 6; FIG. 11 is a plan view showing the first main surface side of a crystal diaphragm according to Modification 7; FIG. 21 is a plan view showing the first main surface side of a crystal diaphragm according to Modification 8; FIG. 21 is a plan view showing the first main surface side of a crystal diaphragm according to Modification 9; FIG. 20 is a cross-sectional view showing a crystal diaphragm according to Modification 10;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that in the following embodiments, a case where the crystal oscillator device to which the present invention is applied is a crystal resonator will be described.

First, the basic structure of the crystal oscillator 100 according to this embodiment will be described. As shown in FIGS. 1 to 3, the crystal oscillator 100 includes a crystal plate (crystal oscillator) 10, and an upper sealing member 20 and a lower sealing member 30 made of crystal. . In the crystal oscillator 100, the crystal plate 10 and the upper sealing member 20 are joined by the sealing portion 115, and the crystal plate 10 and the lower sealing member 30 are joined by the sealing portion 116, thereby forming a substantially rectangular parallelepiped. A package with a three-ply structure is constructed. An internal space (cavity) 110 of the package is formed by bonding the upper sealing member 20 and the lower sealing member 30 to both main surfaces of the crystal diaphragm 10 , respectively. is hermetically sealed. Specifically, a concave portion 21 formed in the surface of the upper sealing member 20 facing the crystal plate 10 and a concave portion 31 formed in the surface of the lower sealing member 30 facing the crystal plate 10 An internal space 110 capable of accommodating the vibrating portion 11 of the crystal plate 10 is formed. Protrusions 22 and 32 are formed on the bottom surfaces of the recesses 21 and 31 . The crystal resonator 100 can be mounted on an external circuit board (mounting board) provided outside, for example, by using solder or the like.

As shown in FIGS. 1 and 2, the crystal plate (crystal vibration element) 10 according to the present embodiment is a piezoelectric substrate made of crystal, and has both main surfaces (a first main surface 101 and a second main surface). 102) is formed as a flat smooth surface (mirror finish). In this embodiment, an AT-cut crystal plate that performs thickness-shear vibration is used as the crystal plate 10 . In the crystal diaphragm 10 of this embodiment, both main surfaces 101 and 102 of the crystal diaphragm 10 are XZ' planes. In this XZ′ plane, the direction parallel to the short side direction (short side direction) of the crystal diaphragm 10 is the Z′ axis direction, and the direction parallel to the longitudinal direction (long side direction) of the crystal diaphragm 10 is the X axis. direction. In addition, the AT cut is 35° around the X axis with respect to the Z axis among the three crystal axes of artificial quartz, the electrical axis (X axis), the mechanical axis (Y axis), and the optical axis (Z axis). This is a processing method for cutting at an angle inclined by 15'. In an AT-cut quartz plate, the X-axis coincides with the crystallographic axis of the quartz. The Y'-axis and Z'-axis are inclined approximately 35°15' from the Y-axis and Z-axis of the quartz crystal axis, respectively (this cut angle may be changed slightly within the range of adjusting the frequency-temperature characteristics of the AT-cut quartz diaphragm. (may be). The Y'-axis direction and the Z'-axis direction correspond to the cutting direction when cutting out an AT-cut crystal plate.

The crystal diaphragm 10 includes a vibrating portion 11 that is substantially rectangular in plan view, a frame-like frame portion 12 that is spaced apart from the outer circumference of the vibrating portion 11 by a predetermined distance, and a predetermined width and thickness. and connection portions 13 and 14 made of a metal film having The excitation electrodes 111 and 112 formed on the vibrating portion 11 and the electrodes 121 and 122 formed on the frame portion 12 are connected via the connecting portions 13 and 14 (connecting portions 13a and 14a in FIGS. 1 and 2). are electrically connected. The vibrating portion 11 and the frame portion 12 are electrically and mechanically connected through the connecting portions 13 and 14, which are metal films, but are not integrally connected as crystal, which is the same material. An annular space is provided between the vibrating portion 11 and the frame portion 12 .

As shown in FIGS. 1 to 3, a pair of excitation electrodes (a first excitation electrode 111 and a second excitation electrode 112) each having a substantially rectangular shape in a plan view are formed on both main surfaces of the vibrating portion 11. there is A plurality of connecting portions 13 are formed on the first main surface 101 side of the crystal diaphragm 10 . The plurality of connecting portions 13 are provided on a pair of opposing sides of the vibrating portion 11 that face each other in the short side direction (Z′-axis direction). The plurality of connecting portions 13 are provided along the short side direction of the vibrating portion 11 and arranged so as to straddle the vibrating portion 11 and the frame body portion 12 . The plurality of connecting portions 13 are arranged at predetermined intervals in the long side direction (X-axis direction) of the vibrating portion 11 .

One end of one connecting portion (connecting portion located in the center) 13a among the plurality of connecting portions 13 is connected to the first excitation electrode 111 of the vibrating portion 11, and the other end of this connecting portion 13a is connected to the frame portion. It is connected to an electrode 121 formed on 12 . The electrode 121 is connected to the bottom surface of the lower sealing member 30 (package is electrically connected to an external connection terminal 34 formed on the bottom surface of the . A pair of external connection terminals 34 are provided at a predetermined interval on the bottom surface of the lower sealing member 30 . A pair of external connection terminals 34 are provided along the long side direction (X-axis direction) of the lower sealing member 30 .

A plurality of connecting portions 14 are formed on the second main surface 102 side of the crystal diaphragm 10 . The plurality of connecting portions 14 are provided on a pair of opposing sides of the vibrating portion 11 that face each other in the long side direction (X-axis direction). The plurality of connecting portions 14 are provided along the long side direction of the vibrating portion 11 and are arranged so as to straddle the vibrating portion 11 and the frame body portion 12 . The plurality of connecting portions 14 are arranged at predetermined intervals in the short side direction (Z′-axis direction) of the vibrating portion 11 . A connecting portion 14a is also provided on one side of the vibrating portion 11 in the short side direction. One end of the connecting portion 14 a is connected to the second excitation electrode 112 of the vibrating portion 11 , and the other end of the connecting portion 14 a is connected to the electrode 122 formed on the frame portion 12 . The electrodes 121 are electrically connected to external connection terminals 34 formed on the bottom of the lower sealing member 30 via electrodes in through holes 36 formed in the lower sealing member 30 .

The plurality of connecting portions 13 and 14 are formed with the same thickness. The connecting portions 13 are formed to have the same width (width in the X-axis direction) and the same length (width in the Z′-axis direction) except for the connecting portion 13a connected to the first excitation electrode 111. . The connecting portion 13 a has a larger width in the Z′-axis direction than the other connecting portions 13 . The connecting portions 14 are formed to have the same width (width in the Z′-axis direction) and the same length (width in the X-axis direction) except for the connecting portion 14a connected to the second excitation electrode 112. . The connecting portion 14 a has a larger width in the Z′-axis direction than the other connecting portions 14 .

The first and second excitation electrodes 111 and 112, the electrodes 121 and 122, and the connecting portions 13 and 14 are formed by laminating a plurality of metal films on the crystal plate 10. As shown in FIG. For example, the first and second excitation electrodes 111 and 112 and the electrodes 121 and 122 are formed by depositing or sputtering a Ti (titanium) film or a Cr (chromium) film as a base film on the crystal plate 10. , and an Au (gold) film is formed on the underlying film by vapor deposition or sputtering. The connecting portions 13 and 14 are formed of an Au (gold) film by removing a Ti (titanium) film or a Cr (chromium) film as a base film. If the electrodes and the metal film formed on the quartz crystal plate 10 have the same structure, the electrodes and the metal film can be patterned at the same time, which is preferable.

Note that the vibrating portion 11 and the frame portion 12 of the quartz plate 10 are formed by wet etching from one quartz plate. Specifically, when the outer shape of the vibrating portion 11 is formed by wet etching, a space is formed between the vibrating portion 11 and the frame portion 12 to separate the vibrating portion 11 and the frame portion 12 from each other. ing. Then, by leaving a part of the metal mask used in the wet etching and further removing the underlying film, connecting portions 13 and 14 made of Au films are formed. are held by the frame body portion 12 .

The connecting portions 13 and 14 are provided at positions that are not electrically connected to the seal portions 115 and 116 formed on the outer peripheral edge of the crystal plate 10 . The seal portions 115 and 116 and the connecting portions 13 and 14 are provided at positions not electrically connected to the first and second excitation electrodes 111 and 112 except for the connecting portions 13a and 14a. The seal portions 115 and 116 are provided to hermetically seal the vibrating portion 11 of the crystal plate 10 in the crystal oscillator 100, and are formed in an annular shape in plan view. The sealing portion 115 is formed by diffusion bonding (Au -Au bonding). The sealing portion 116 is formed by diffusion bonding ( Au—Au bonding).

In this embodiment, as described above, the first and second excitation electrodes 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, 111, and 112 and the electrodes 121 and 122 of the frame portion 12 are electrically connected, and the vibrating portion 11 is held by the frame portion 12 by the connecting portions 13 and 14 .

According to this embodiment, the internal space 110 is formed between the vibrating portion 11 and the frame portion 12, and the vibrating portion 11 is separated from the frame portion 12. Therefore, the flow from the frame portion 12 to the vibrating portion 11 The transmission of heat and stress is cut off. As a result, it is possible to reduce environmental stress due to heat acting on the vibrating portion 11 and external force, etc., and it is possible to suppress fluctuations in vibration characteristics.

Here, in a configuration in which a plurality of wires are used to support the vibrating portion 11 , the stress caused by the wires pulling each other due to the plurality of wire bridges may affect the vibrating portion 11 and the frame body portion 12 . Since it is necessary to secure a formation area for the wire connection pads, there is a concern that miniaturization of the crystal diaphragm 10 will become difficult. However, in the present embodiment, since the vibrating portion 11 is not affected by such stress, fluctuations in vibration characteristics can be suppressed. In addition, since it is unnecessary to secure a formation area for the wire connection pads in the vibrating portion 11 and the frame portion 12, the size of the crystal plate 10 can be reduced.

In the present embodiment, since the connecting portions 13 and 14 are configured to include at least an Au film, the ductility and malleability of Au make it difficult for the holding strength of the vibrating portion 11 by the connecting portions 13 and 14 to decrease. Environmental changes and secular changes in the parts 13 and 14 can be suppressed.

Further, in the present embodiment, the connection portions with the vibrating portion 11 and the connection portions with the frame body portion 12 in the connecting portions 13 and 14 have a configuration in which an Au film is laminated on a Cr film or a Ti film. there is Since Cr or Ti has good adhesion to crystal, the bonding strength between the connecting portions 13 and 14 and the vibrating portion 11 and the bonding strength between the connecting portions 13 and 14 and the frame portion 12 can be improved.

In this embodiment, since at least one connecting portion 13, 14 is formed on each side of the vibrating portion 11, the holding of the vibrating portion 11 by the connecting portions 13, 14 can be stabilized. Further, since the connecting portions 13 and 14 are formed on at least a pair of opposing sides of the substantially rectangular vibrating portion 11 in plan view, the vibrating portion 11 tilts and rotates with respect to the frame portion 12 . Therefore, the stability of holding the vibrating portion 11 by the connecting portions 13 and 14 can be enhanced.

Further, in the present embodiment, three or more connecting portions 13 are formed for one side of the vibrating portion 11, and the width and/or thickness of the connecting portion 13 on the outer side is greater than the width and/or thickness of the connecting portion 13 on the central side in plan view. The width and/or thickness of 13 are greater. 1 and 2, five connecting portions 13 are formed, and the width of the other connecting portions 13 is larger than the width (width in the X-axis direction) of the central connecting portion 13a. ing. Thus, when the width and thickness of the outer connecting portion 13 are large and the width and thickness of the inner connecting portion 13a are small, the stress acting on the inner connecting portion 13a can be easily released, and the vibration portion 11 can withstand shock. Since the strength is improved, breakage of the connecting portion 13 can be suppressed. Note that breaking of the connecting portion 13 may be suppressed by adjusting either one of the width and thickness of the connecting portion 13 .

The crystal oscillator 100 including the crystal diaphragm 10 according to the present embodiment can also obtain the same effect as the crystal diaphragm 10 having the above configuration. In the crystal resonator 100, the upper sealing member 20 and the lower sealing member 30 are formed with the concave portions 21 and 31 on the side of the crystal diaphragm 10, respectively, and the vibrating portion 11 is formed on the bottom surfaces of the concave portions 21 and 31, respectively. , the movable area of the vibrating portion 11 can be secured, and even if the vibrating portion 11 slightly moves due to an external impact or the like, the upper sealing member 20 or the lower sealing member 30 does not move. You can prevent contact. Moreover, since the convex portions 22 and 32 are formed on the bottom surfaces of the concave portions 21 and 31 at positions facing the vibrating portion 11, the first and second excitation electrodes 111 and 112 of the vibrating portion 11 may be displaced by an external impact or the like. While securing a movable region by the recesses 21 and 31 for the region where is formed, the region where the first and second excitation electrodes 111 and 112 of the vibrating portion 11 are not formed on the bottom surface of each recess 21 and 31 By providing the protrusions 22 and 32 at positions facing the , the amount of vertical displacement of the vibrating portion 11 can be suppressed. As a result, breakage of the connecting portions 13 and 14 can be suppressed. In addition, the number of each protrusion 22, 32 is not limited to two, and may be one or three or more.

The embodiments disclosed this time are illustrative in all respects, and are not grounds for restrictive interpretation. Therefore, the technical scope of the present invention is not to be interpreted only by the above-described embodiments, but is defined based on the description of the claims. In addition, all changes within the meaning and range of equivalents to the scope of claims are included.

The size and shape of the vibrating portion 11 and the arrangement position on the crystal plate 10 described above are examples, and can be changed in various ways. The sizes, shapes, and numbers of the connecting portions 13 and 14 described above, and the arrangement positions on the crystal plate 10 are only examples, and can be changed in various ways.

Also, the electrical wiring to the first and second excitation electrodes 111 and 112 of the vibrating section 11 described above is an example, and various modifications are possible. In the above embodiment, the through holes 35, 36, 123 are formed for electrical connection, but instead of such through holes, castellations are formed on the side surfaces of the lower sealing member 30, Electrical connection may be made by forming electrodes on the inner wall surface. Alternatively, through holes and castellations may be used in combination.

In the above-described embodiment, as the crystal resonator 100, a crystal resonator having a three-layer structure in which the crystal diaphragm 10 is sandwiched between the upper sealing member 20 and the lower sealing member 30 is used. A crystal oscillator 100 having a structure may be used. For example, a crystal resonator having a structure in which the crystal plate 10 is housed inside a base (lower sealing member) having a recess and a lid (upper sealing member) is bonded to the base may be used. In this case, the quartz plate 10 is bonded to the base by, for example, a conductive adhesive.

In the above embodiment, the upper sealing member 20 and the lower sealing member 30 are made of crystal, but the upper sealing member 20 and the lower sealing member 30 may be made of ceramic, glass, or the like. .

In the above embodiment, the case where the present invention is applied to the crystal oscillator 100 has been described, but the present invention is not limited to this, and may be applied to, for example, a crystal oscillator or the like.

Hereinafter, a plurality of modified examples will be described, but the description of the same parts as the above embodiment will be omitted, and the different parts from the above embodiment will be mainly described.

Modification 1 shown in FIGS. 4 and 5 is mainly different from the above-described embodiment in the configuration of connecting portions 13 and 14 and electrodes 15 for mounting on the base.

As shown in FIGS. 4 and 5, a pair of mounting electrodes 15 are provided on one end side of the crystal diaphragm 10 in the long side direction (X-axis direction). A plurality of connecting portions 13 are provided along the short side direction (Z′-axis direction) of the crystal plate 10 on the first main surface 101 side of the crystal plate 10 . The plurality of connecting portions 13 are bridged between the vibrating portion 11 and the frame portion 12 only in the long side direction of the crystal plate 10 . Among the plurality of connecting portions 13 , one connecting portion (connecting portion located in the center) 13 a is connected to the first excitation electrode 111 . A plurality of (three in FIG. 4) connecting portions 13 including the connecting portion 13 a are connected to the mounting electrode 15 . In this case, the plurality of connecting portions 13 including the connecting portion 13a are electrically connected by a connecting electrode 16a formed on the vibrating portion 11 side and a connecting electrode 16b formed on the frame portion 12 side. The connection electrodes 16 a and 16 b are formed along the long side direction of the crystal plate 10 , and one end of the connection electrode 16 b is connected to the mounting electrode 15 . In this manner, a plurality of connecting portions 13 are commonly connected to the mounting electrodes 15 . Note that the connection electrode 16a may be formed over the entire circumference of the vibrating portion 11 .

A plurality of connecting portions 14 are provided along the long side direction of the crystal diaphragm 10 on the second main surface 102 side of the crystal diaphragm 10 . The plurality of connecting portions 14 are bridged between the vibrating portion 11 and the frame portion 12 only in the short side direction of the crystal plate 10 . An extraction electrode 16 c extending from the second excitation electrode 112 is connected to one connecting portion (connecting portion located at an end) 14 b of the plurality of connecting portions 14 . The connecting portion 14 b is connected to the mounting electrode 15 . In this case, all of the plurality of connecting portions 14 including the connecting portion 14b are electrically connected by the connecting electrode 16d formed on the vibrating portion 11 side and the connecting electrode 16e formed on the frame portion 12 side. there is The connection electrodes 16d and 16e are formed along the short side direction of the crystal diaphragm 10. As shown in FIG. In this manner, a plurality of connecting portions 14 are commonly connected to the mounting electrodes 15 . Note that the connection electrode 16 d may be formed over the entire outer periphery of the vibrating portion 11 .

In the crystal diaphragm 10 according to Modification 1, the vibrating portion 11 is substantially rectangular in plan view, and the connecting portion 13 is provided only on the long side of the vibrating portion 11 on the first main surface 101 of the crystal diaphragm 10 . A connecting portion 14 is formed only on the short side of the vibrating portion 11 on the second main surface 102 of the crystal plate 10 . According to this configuration, the connecting portion 13 is not formed on the short side of the vibrating portion 11 on the first main surface 101 of the crystal plate 10, and the second main surface 102 of the crystal plate 10 has Since the connecting portion 14 is not formed on the long side of the vibrating portion 11, when performing the outer shape processing of the vibrating portion 11 by wet etching, the etching can be performed with high accuracy.

In addition, since the plurality of connecting portions 13 and 14 are commonly connected to the mounting electrode 15, even if one of the plurality of connecting portions 13 and 14 is broken, the remaining connecting portions 13 and 14 can be used. , the first and second excitation electrodes 111 and 112 and the mounting electrode 15 can be secured.

Modification 2 shown in FIG. 6 is mainly different from the above-described embodiment in the configuration of mounting electrodes 15 on the base. As shown in FIG. 6, electrodes 15 for mounting on the base are provided at the four corners of the frame portion 12 of the crystal diaphragm 10 .

When the crystal plate 10 shown in FIGS. 4 and 5 is mounted on the base, the mounting electrodes 15 of the crystal plate 10 are bonded to the mounting pads of the base by, for example, a conductive adhesive. Since the mounting electrode 15 is provided only on one end side of the crystal diaphragm 10 in the long side direction (X-axis direction), the crystal diaphragm 10 is supported by the base in a cantilevered state. However, in the crystal diaphragm 10 according to Modification 21, since the mounting electrodes 15 are provided at the four corners of the crystal diaphragm 10, the crystal diaphragm 10 can be stably supported on the base. As a result, no unnecessary stress acts on the connecting portions 13 and 14, which is preferable in terms of impact resistance of the vibrating portion 11. FIG.

Modification 3 shown in FIG. 7 is mainly different from the above-described embodiment in the configuration of connecting portions 13 and 14 . As shown in FIG. 7 , two connecting portions 13 among the plurality of connecting portions 13 are provided at a pair of diagonal positions of the crystal plate 10 on the first main surface 101 side of the crystal plate 10 . The two connecting portions 13 are provided over a corner portion of the vibrating portion 11 and a corner portion on the inner peripheral side of the frame portion 12 . One end of one connecting portion 13a among the plurality of connecting portions 13 is connected to the first excitation electrode 111 of the vibrating portion 11, and the other end of this connecting portion 13a is connected to the electrode formed on the frame portion 12. 121.

On the second main surface 102 side of the crystal plate 10 , two of the plurality of connection portions 14 are provided at the remaining pair of diagonal positions of the crystal plate 10 . The two connecting portions 14 are provided over a corner portion of the vibrating portion 11 and a corner portion on the inner peripheral side of the frame portion 12 . One end of one connecting portion 14 a of the plurality of connecting portions 14 is connected to the second excitation electrode 112 of the vibrating portion 11 , and the other end of this connecting portion 14 a is connected to the electrode formed on the frame portion 12 . 122.

In the crystal diaphragm 10 according to the third modification, the frame portion 12 is substantially rectangular in plan view, and the connecting portions 13 and 14 are connected to the corners of the inner periphery of the frame portion 12 at diagonal positions. Thus, the vibrating portion 11 is held. According to this configuration, since the corners of the inner periphery of the frame body 12, which are portions having a large rotational moment with respect to the center of the vibrating part 11, are held by the connecting parts 13 and 14, the rotating motion of the vibrating part 11 is suppressed. be done. Thereby, the stability of holding the vibrating portion 11 by the connecting portions 13 and 14 can be improved. Note that the shape of the vibrating portion 11 may be other than rectangular.

In Modified Example 4 shown in FIG. 8, a cushioning portion is provided in the connecting portion 13 (the same applies to the connecting portion 14). In FIG. 8A, the cross-sectional shape of the central portion of the connecting portion 13 is circular, and the width of the central portion of the connecting portion 13 (the width in a plan view) is larger than the widths of the portions on both sides thereof. ing. In FIG. 8B, a portion with a large width (width in plan view) and a portion with a small width of the connecting portion 13 are repeatedly provided. In FIG. 8C, the central portion of the connecting portion 13 is hollow. In FIG. 8D, the width of the central portion of the connecting portion 13 (the width in plan view) is smaller than the width of the portions on both sides thereof.

In the crystal diaphragm 10 according to the fourth modification, the width and/or thickness of the central portion in the longitudinal direction of the connecting portions 13 and 14 are larger than those of the portions on both sides thereof. Alternatively, the connecting portions 13, 14 are smaller in width and/or thickness in the central portion in the longitudinal direction than in the portions on both sides thereof. As a result, the connecting portions 13 and 14 are flexible and elastically expandable, so that the impact resistance of the vibrating portion 11 can be improved.

In Modified Example 5 shown in FIG. 9, the connection portion 13 includes a connection portion 13c provided on the side wall of the frame portion 12 and 13d provided on the side wall of the vibrating portion 11 (the connection portion 14 as well). In the crystal diaphragm 10 according to the fifth modification, the connecting portions 13 and 14 are also provided integrally with the side wall of the frame portion 12 and the side wall of the vibrating portion 11. Therefore, the connecting portions 13 and 14 and the vibrating portion 11 and the frame body portion 12 can be improved, and breakage of the connecting portions 13 and 14 can be suppressed even when an external impact is applied. Note that the connecting portions 13 and 14 may be provided on either one of the side wall of the frame portion 12 and the side wall of the vibrating portion 11 .

Modified Example 6 shown in FIG. 10 is mainly different from the above-described embodiment in the configuration of the frame portion 12 . As shown in FIG. 10, the frame portion 12 has a three-sided configuration, and one end side of the crystal plate 10 in the long side direction (X-axis direction) is open. By holding the vibrating portion 11 by at least three sides of the frame portion 12 in this way, the stability of holding the vibrating portion 11 by the connecting portions 13 and 14 can be ensured.

The width (width in the X-axis direction) and/or thickness of the connecting portion 13 provided near the open end of the frame portion 12 is larger than the width and/or thickness of the other connecting portions 13. Therefore, it is possible to suppress breakage of the connecting portion 13 provided in the vicinity of the open end of the frame portion 12 .

Modification 7 shown in FIG. 11 is mainly different from the above embodiment in the configuration of connecting portions 13 and 14 . As shown in FIG. 11 , on the first main surface 101 side of the crystal diaphragm 10 , the width (the width in the X-axis direction) and/or the thickness of the connecting portion 13 on the central side in a plan view are greater than the width (the width in the X-axis direction) and/or the thickness of the connecting portion 13 on the outer side. is greater in width and/or thickness. Specifically, the width of the connecting portion 13 is gradually reduced toward the central side.

In addition, on the second main surface 102 side of the crystal diaphragm 10, the width and/or thickness of the outer connecting portion 14 is greater than the width (the width in the Z′-axis direction) and/or the thickness of the central connecting portion 14 in plan view. Or the thickness is greater.

In the crystal diaphragm 10 according to the modification 7, the width and thickness of the outer connecting portions 13 and 14 are increased, and the width and thickness of the inner connecting portions 13 and 14 are decreased. Since the stress acting on 14 is easily released and the impact resistance of vibrating portion 11 is improved, breakage of connecting portions 13 and 14 can be suppressed. In addition, the width and thickness of the connecting portions 13 and 14 near the corners of the inner circumference of the frame body portion 12 are large, and the width of the connecting portions 13 and 14 at portions where the rotational moment with respect to the center of the vibrating portion 11 is large. , the thickness is increased, so that the rotating motion of the vibrating portion 11 is suppressed. Thereby, the stability of holding the vibrating portion 11 by the connecting portions 13 and 14 can be improved. Note that breaking of the connecting portions 13 and 14 may be suppressed by adjusting either one of the width and thickness of the connecting portions 13 and 14 .

Modification 8 shown in FIG. 12 is mainly different from the above embodiment in the configuration of connecting portions 13 and 14 . As shown in FIG. 12, the connecting portions 13 and 14 are configured to have bent portions. The connecting portions 13 and 14 have a bent portion in the central portion in the length direction, and the bent portion is formed in a shape having a curvature. In the connecting portion 14, the bent portions of adjacent connecting portions 14 are connected to each other. The connecting portions 13 and 14 are formed, for example, in a "<" shape, an X shape, a mesh shape, or the like in plan view.

On the first main surface 101 side of the crystal diaphragm 10, the plurality of connecting portions 13 are electrically connected by the connection electrodes 16a formed on the vibrating portion 11 side and the connection electrodes 16b formed on the frame portion 12 side. connected to each other. The connection electrodes 16a and 16b are formed along the long side direction (X-axis direction) of the crystal diaphragm 10. As shown in FIG. In this manner, the connection electrodes 16a and 16b connect the plurality of connecting portions 13 to the first excitation electrode 111 in common.

On the second main surface 102 side of the crystal diaphragm 10, the plurality of connecting portions 14 are electrically connected by the connection electrodes 16d formed on the vibrating portion 11 side and the connection electrodes 16e formed on the frame portion 12 side. connected to each other. The connection electrodes 16 d and 16 e are formed along the short side direction (Z′-axis direction) of the crystal plate 10 . In this way, a plurality of connecting portions 14 are commonly connected to the second excitation electrode 112 by the connection electrodes 16d and 16e.

In the crystal diaphragm 10 according to Modification 8, the connecting portions 13 and 14 are elastically expandable and contractable when stress acts, so breakage of the connecting portions 13 and 14 can be suppressed, and the vibrating portion 11 impact resistance can be improved. Moreover, since the bent portions of the connecting portions 13 and 14 have a curved shape, breakage of the connecting portions 13 and 14 can be suppressed more reliably. Further, since the plurality of connecting portions 13 and 14 are commonly connected to the first and second excitation electrodes 111 and 112, even if one of the plurality of connecting portions 13 and 14 is broken, the remaining Electrical connection between the first and second excitation electrodes 111 and 112 and the electrodes 121 and 122 of the frame portion 12 can be ensured by the connecting portions 13 and 14 .

Metal films (connection electrodes 16a, 16b, 16d, and 16e) are formed on the inner periphery of the frame portion 12 and the outer periphery of the vibrating portion 11, respectively. , 14 bridge the frame portion 12 and the vibrating portion 11 . According to this configuration, even if some of the plurality of connecting portions 13 and 14 are disconnected when an external impact is applied, electrical connection can be ensured by the metal film formed over substantially the entire circumference. can improve reliability.

Modification 9 shown in FIG. 13 is mainly different from the above embodiment in the configuration of connecting portions 13 and 14 . As shown in FIG. 13 , on the first main surface 101 side of the crystal diaphragm 10 , the connecting portion 13 has a sheet-like configuration that is wide in the long side direction (X-axis direction) of the crystal diaphragm 10 . A plurality of circular or elliptical through holes (openings) 13e are formed in a portion of the connecting portion 13 located between the vibrating portion 11 and the frame portion 12, for example. The plurality of through holes 13 e are arranged in a line along the long side direction of the crystal plate 10 . The connecting portion 13 has, for example, a configuration in which the plurality of connecting portions 13 and the connection electrodes 16a and 16b of Modification 8 described above are integrally formed.

On the second main surface 102 side of the crystal diaphragm 10 , the connecting portion 14 has a sheet-like configuration that is wide in the short side direction (Z′-axis direction) of the crystal diaphragm 10 . A plurality of through holes 14 e having a circular or oval shape, for example, are formed in a portion of the connecting portion 14 located between the vibrating portion 11 and the frame portion 12 . A plurality of through-holes (openings) 14 e are arranged in a row along the short side direction of the crystal plate 10 . The connecting portion 14 has, for example, a configuration in which the plurality of connecting portions 14 and the connection electrodes 16d and 16e of Modification 8 described above are integrally formed.

In the crystal diaphragm 10 according to the ninth modification, both the frame portion 12 and the vibrating portion 11 are bridged by a wide metal film, and the metal film is provided with a plurality of through holes 13e and 14e to form the connection portion. 13 and 14 are formed. According to this configuration, the stress acting on the connecting portions 13 and 14 can be relieved by the connecting portions 13 and 14 provided with the plurality of openings 13e and 14e. Moreover, since the inner peripheries of the plurality of through holes 13e and 14e are curved surfaces and do not have corners, the stress acting on the connecting portions 13 and 14 can be further alleviated. Note that the plurality of through holes 13e and 14e may be arranged in a plurality of rows (for example, two rows).

Modification 10 shown in FIG. 14 is mainly different from the above embodiment in the configurations of vibrating portion 11 and frame portion 12 . As shown in FIG. 14, the thicknesses of the vibrating portion 11 and the frame portion 12 are not the same, but are varied.

In FIG. 14A, the thickness of the vibrating portion 11 is smaller than the thickness of the frame portion 12 (reverse mesa structure). The thickness of the vibrating portion 11 is the same throughout. A stepped portion 12a is formed in the frame portion 12, and the stepped portion 12a is continuously formed in a circumferential shape in plan view. The steps 12 a are provided on both the first main surface 101 and the second main surface 102 of the crystal plate 10 . The thickness of the portion of the frame body portion 12 on the inner peripheral side of the step 12 a is substantially the same as the thickness of the vibrating portion 11 . The thickness of the portion of the frame body portion 12 on the outer peripheral side of the step 12 a is larger than the thickness of the vibrating portion 11 .

In this manner, a thin portion having substantially the same thickness as the vibrating portion 11 and thinner than the outer peripheral side of the frame portion 12 is provided on the vibrating portion 11 side (inner peripheral side) of the frame portion 12 . With this configuration, there is no height difference between the thin portion of the frame portion 12 and the vibrating portion 11, and unnecessary tension is less likely to act on the connecting portions 13 and 14, thereby ensuring stable electrical connection. can improve reliability.

In FIG. 14B, the thickness of the central portion of the vibrating portion 11 is larger than the thickness of the outer peripheral portion (mesa structure). A stepped portion 11a is formed in the vibrating portion 11, and the stepped portion 11a is continuously formed in a circumferential shape in plan view. The steps 11a are provided on both the first main surface 101 and the second main surface 102 of the quartz plate 10 . The thickness of the central portion of the vibrating portion 11 on the inner peripheral side of the step 11a is larger than the thickness of the outer peripheral portion of the step 12a on the outer peripheral side. Excitation electrodes 111 and 112 are formed. A stepped portion 12a is also formed in the frame portion 12, and the stepped portion 12a is continuously formed in a circumferential shape in plan view. The steps 12 a are provided on both the first main surface 101 and the second main surface 102 of the crystal plate 10 . The thickness of the portion of the frame body portion 12 on the inner peripheral side of the step 12 a is substantially the same as the thickness of the outer peripheral portion of the vibrating portion 11 . The thickness of the portion of the frame body portion 12 on the outer peripheral side of the step 12 a is larger than the thickness of the central portion of the vibrating portion 11 .

In FIG. 14C, the thickness of the vibrating portion 11 is smaller than the thickness of the frame portion 12 (reverse mesa structure). The thickness of the vibrating portion 11 is the same throughout. A stepped portion 12a is formed in the frame portion 12, and the stepped portion 12a is continuously formed in a circumferential shape in plan view. The step 12a is provided only on the first main surface 101 of the crystal diaphragm 10, and is not provided on the second main surface 102, unlike the case of FIGS. do not have. The thickness of the portion of the frame body portion 12 on the inner peripheral side of the step 12 a is substantially the same as the thickness of the vibrating portion 11 . The thickness of the portion of the frame body portion 12 on the outer peripheral side of the step 12 a is larger than the thickness of the vibrating portion 11 . On the second main surface 102 side of the crystal diaphragm 10, the surface of the vibrating portion 11 and the surface of the frame portion 12 are formed substantially on the same plane.

10 crystal plate (crystal vibration element)
REFERENCE SIGNS LIST 11 vibrating section 12 frame body section 13, 14 connecting section 100 crystal oscillator (crystal oscillation device)
111, 112 first and second excitation electrodes 121, 122 electrodes

Claims (18)

a vibrating part;
a frame portion provided at a predetermined interval from the outer periphery of the vibrating portion;
a connecting portion made of a metal film having a predetermined width and thickness;
An electrode of the vibrating portion and an electrode of the frame are electrically connected to each other through the connecting portion, and the vibrating portion is held by the frame by the connecting portion. Crystal oscillator element to be. In the crystal resonator element according to claim 1,
A quartz-crystal vibrating element, wherein the frame has at least three sides. 3. In the crystal resonator element according to claim 1,
A crystal oscillator according to claim 1, wherein the vibrating portion is rectangular in plan view, and the connecting portion is formed on at least one pair of opposing sides of the vibrating portion. In the crystal resonator element according to claim 1,
A quartz-crystal vibrating element, wherein the vibrating portion is rectangular in plan view, and at least one connecting portion is formed on each side of the vibrating portion. In the crystal resonator element according to any one of claims 2 to 4,
A crystal vibrating element, wherein a plurality of said connecting portions are formed on one side of said vibrating portion, and the width and/or thickness of each connecting portion are different. In the crystal resonator element according to any one of claims 2 to 4,
Three or more connecting portions are formed for one side of the vibrating portion, and the width and/or thickness of the connecting portions on the outer side are greater than the width and/or thickness of the connecting portions on the central side in plan view. 1. A crystal resonator element characterized in that the diameter is larger. In the crystal resonator element according to any one of claims 1 to 6,
A crystal resonator element, wherein the connecting portion includes at least an Au film. In the crystal resonator element according to any one of claims 1 to 7,
A quartz-crystal vibrating element according to claim 1, wherein the connection portion with the vibrating portion and the connection portion with the frame portion of the connecting portion are configured such that an Au film is laminated on a Cr film or a Ti film. . In the crystal resonator element according to any one of claims 1 to 8,
The frame body portion is rectangular in plan view,
A quartz-crystal vibrating element, wherein the vibrating portion is held by connecting the connecting portions to diagonal positions of the corners of the inner periphery of the frame portion. In the crystal resonator element according to any one of claims 1 to 9,
The vibrating portion has a rectangular shape in plan view, and the connecting portion is formed only on the long side on one main surface of the vibrating portion, and the connecting portion is formed only on the short side on the other main surface of the vibrating portion. A quartz-crystal vibrating element, wherein the connecting portion is formed. In the crystal resonator element according to any one of claims 1 to 10,
A crystal resonator element, wherein a buffer portion is provided in the connecting portion. In the crystal resonator element according to any one of claims 1 to 11,
A quartz-crystal vibrating element, wherein the connecting portion is also provided on a side wall of the frame portion and/or a side wall of the vibrating portion. In the crystal resonator element according to any one of claims 1 to 12,
The vibrating portion is rectangular in plan view, and the connecting portion has a structure in which a metal film is formed over the entire circumference of each of the inner peripheral portion of the frame portion and the outer peripheral portion of the vibrating portion,
A quartz-crystal vibrating element, wherein the connecting portion bridges the frame portion and the vibrating portion. In the crystal resonator element according to any one of claims 1 to 12,
A crystal vibrating element, wherein both the frame portion and the vibrating portion are bridged by a wide metal film, and the connecting portion is formed by providing a plurality of openings in the metal film. . In the crystal resonator element according to any one of claims 1 to 14,
A crystal vibrating element, wherein a thin portion having substantially the same thickness as the vibrating portion and being thinner than the frame portion is provided on the vibrating portion side of the frame portion. A quartz crystal oscillation device, wherein the quartz crystal oscillation element according to any one of claims 1 to 15 is hermetically sealed with an upper sealing member and a lower sealing member. 17. The crystal oscillator device of claim 16,
A crystal oscillation device, wherein the upper sealing member and the lower sealing member each have a concave portion formed on the side of the crystal oscillation element, and the vibrating portion faces the bottom surface of each concave portion. 18. The crystal oscillator device of claim 17,
A quartz crystal oscillation device, wherein a projection is formed on the bottom surface of each of the recesses at a position facing the vibrating portion.

Images