Tuning-fork type crystal vibrator, crystal device, and intermediate wafer

Abstract

To provide a tuning-fork type crystal vibrator having a novel structure capable of surely performing an electrode division in a support arm of a tuning-fork type crystal vibrator of three arm structures as compared with a conventional art.SOLUTION: A tuning-fork type crystal vibrator 10 comprises: a base part 11; a first oscillation arm 13a and a second oscillation arm 13b; a support arm 15; a first oscillation electrode 17a and a second oscillation electrode 17b; and a first connection pad provided to a tip end side of the support arm for connecting those oscillation electrodes to an external part 17ax and a second connection pad 17bx provided to the base part side of the support arm. Then, a region as a space between the first and second pads of the support arm, comprises: a first notch 15a that is parallel to a first 1X shaft X1 of a crystal; and a second notch 15b that is parallel to a second 2X shaft X2 caused that the crystal is a trigonal system.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a tuning-fork type quartz crystal resonator having a three-arm structure, a quartz crystal device using the same, and an intermediate wafer for manufacturing the tuning-fork type quartz crystal resonator. [Background technology]

[0002] As a tuning fork type crystal resonator that is advantageous for miniaturization, there is a tuning fork type crystal resonator with a so-called three-arm structure. One example is disclosed in, for example, Patent Document 1. This tuning fork type crystal resonator includes a base, a first vibrating arm and a second vibrating arm extending in parallel in the same direction from the base, and a support arm extending in parallel in the same direction as the vibrating arms from the base between the vibrating arms. The first and second vibrating arms are provided with two excitation electrodes of different polarities in a predetermined arrangement. Extraction electrodes are drawn from these excitation electrodes to the support arms. The ends of these extraction electrodes serve as first and second connection pads for fixing the tuning fork crystal unit to a container.

[0003] Although not described in detail, the above-mentioned excitation electrodes, extraction electrodes, first connection pads, and second connection pads are formed by forming a metal film for forming electrodes on the entire surface of the main body after forming a tuning fork-type crystal piece with a three-arm structure, and then patterning this metal film into a predetermined shape using photolithography and metal etching techniques. In this case, in order to form the first and second connection pads concentrated on the support arms, it is necessary to devise a way to electrically divide the metal film provided on the side of the support arms. Therefore, in the three-arm tuning fork crystal resonator disclosed in Patent Document 1, a notch is provided on each side of the support arm in the width direction in the middle of the support arm in the longitudinal direction, and the metal film is patterned by utilizing the slopes caused by the etching anisotropy of the crystal axis of the crystal that are generated in these two notches. In particular, the notch provided on the -X axis side of the crystal is provided with a two-step structure. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2022-125526 Summary of the Invention [Problem to be solved by the invention]

[0005] Specifically, the idea of ​​dividing the metal film using two notches described in Patent Document 1 is as follows. First, the reason for providing a notch on the +X side of the crystal is that the notch on the +X side of the crystal utilizes a well-known inclined surface that creates an inclined surface that slopes from both main surfaces of the support arm toward the +X axis side of the crystal. Also, the reason for providing a two-stage notch on the -X side of the crystal is to improve the difficulty in dividing the electrode because the side surface on the -X side of the support arm becomes a vertical wall due to the crystallinity of the crystal, and the two-stage notch on the -X side of the support arm intentionally creates an inclined surface to promote division of the metal film. Although the structure disclosed in Patent Document 1 facilitates electrode division in the supporting arms, there is still room for improvement. This application has been made in consideration of the above points, and therefore an object of the present invention is to provide a tuning-fork type quartz crystal resonator having a new structure that can ensure electrode division in the supporting arms of a three-arm tuning-fork type quartz crystal resonator compared to conventional techniques. [Means for solving the problem]

[0006] In order to achieve this object, a tuning-fork type crystal resonator of the present invention comprises a base, first and second vibrating arms extending parallel to each other from the base, a support arm extending from the base between the vibrating arms, a first excitation electrode and a second excitation electrode disposed on the first and second vibrating arms, a first connection pad provided on a tip side of the support arm and a second connection pad provided on a base side of the support arm in order to connect the first excitation electrode and the second excitation electrode to an outside, and at least a pair of notches provided on both sides along the width direction of the support arm in a region midway in the longitudinal direction of the support arm and between the first connection pad and the second connection pad, When the X-axis of the crystal parallel to the width direction of the tuning fork crystal unit is defined as the first X-axis, and the X-axes 120 degrees symmetrical to the first X-axis due to the fact that the crystal is a trigonal crystal system are defined as the second X-axis and the third X-axis, respectively, a first notch of the pair of notches is parallel to the first X-axis and terminates in a -X direction of the first X-axis; The second notch of the pair of notches is parallel to the second X-axis or the third X-axis and terminates in the -X direction of this axis. It is characterized by:

[0007] In carrying out the invention of the tuning-fork type quartz crystal resonator, a third notch may be provided on the tip side, which is opposite to the base part of the supporting arm, in parallel with the second X-axis or the third X-axis and terminates in the -X direction of this axis (see FIG. 2(B)). Furthermore, in carrying out the invention of the tuning-fork type quartz crystal resonator, in addition to the pair of notches, one or more third notches may be provided midway along the longitudinal direction of the supporting arm, the third notches being parallel to the first X-axis, the second X-axis or the third X-axis and terminating in the -X direction of this axis.

[0008] Furthermore, in carrying out the invention of the tuning fork type quartz crystal unit, when the first notch, the second notch, and the third notch are provided, the third notch must have appropriate width and depth dimensions (shown as D1, W1, etc. in FIG. 2(B)) that can provide a crystal face (inclined face) originating from the +X face of the quartz crystal at the end of the notch and that can facilitate exposure. Moreover, since the first notch, the second notch, and the third notch are formed by wet etching, the width and depth dimensions are determined in consideration of the thickness of the tuning fork type quartz crystal unit (the dimension in the Z' direction in FIG. 1(A)). Specific examples will be described in the embodiment section.

[0009] Also, if the tuning fork type quartz crystal resonator is too thin, it is difficult to close the ends of the notches, making it difficult to produce the desired crystal faces (inclined faces), so the thickness of the tuning fork type quartz crystal resonator should be 50 μm or more, preferably 60 μm or more. On the other hand, if the thickness is too thick, problems such as wet etching becoming difficult to process the tuning fork occur, so the upper limit of the thickness should be approximately the thickness of currently available commercially available tuning fork type quartz crystal resonators, for example, about 100 to 120 μm. Effect of the Invention

[0010] The tuning fork type quartz crystal resonator of the present invention uses a structure that focuses on the 120-degree symmetry of the crystal axis due to the fact that quartz crystal is a trigonal crystal system, as an electrode division structure in the support arms of a tuning fork type quartz crystal resonator with a three-arm structure. That is, it is known that when a notch is provided with a -X side as a terminus along the X axis of the quartz crystal, a slope that slopes downward from both main faces of the notch toward the +X side is generated in the notch, but by generating this phenomenon in the second X axis or the third X axis in addition to the first X axis in the support arms, electrode division of the support arms is achieved. Therefore, it is possible to provide a tuning fork type quartz crystal resonator having a new structure that can perform electrical division between the first connection pad and the second connection pad in the support arms more reliably than before. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram for explaining a tuning-fork type crystal resonator 10 according to the first embodiment. [Diagram 2] FIG. 2 is a diagram for explaining an example of a tuning-fork type crystal resonator according to another embodiment. [Diagram 3] FIG. 3 is a scanning electron microscope (SEM) photograph of the first and second notches of an element of an example of the tuning-fork type crystal resonator 10 according to the first embodiment. [Figure 4] FIG. 4 is a diagram for explaining an example of a crystal device using the tuning-fork crystal resonator 10 according to the first embodiment. [Diagram 5] 3A to 3C are diagrams illustrating an example of a method for manufacturing the tuning-fork type crystal resonator 10 according to the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of a tuning fork type crystal resonator of the present invention will be described with reference to the drawings. Note that each drawing used in the description is merely a schematic view to the extent that the present invention can be understood. In addition, in each drawing used in the description, similar components are indicated by the same numbers, and their description may be omitted. Furthermore, the shapes, dimensions, materials, etc. described in the following description are merely preferred examples within the scope of the present invention. Therefore, the present invention is not limited to only the following embodiments.

[0013] 1. Tuning-fork crystal resonator 10 according to the first embodiment FIG. 1 is an explanatory diagram of a tuning fork type quartz crystal resonator 10 according to the first embodiment. In particular, FIG. 1(A) is a development showing the tuning fork type quartz crystal resonator 10 with its front, back and side surfaces developed, and FIG. 1(B) is a cross-sectional view taken along line PP in FIG. 1(A). Also, FIG. 1(C) is a cross-sectional view taken along line QQ in the vicinity of the second notch 15b. In the development view of FIG. 1(A), a three-dimensional tuning fork type quartz crystal resonator 10 can be constructed by folding back the view and connecting it at the α-α point. Here, the coordinate axis in FIG. 1(A) is the crystal axis of the quartz crystal when viewed from the tuning fork part on the right side of the view. In these coordinate axes, X1 is the first X-axis of the quartz crystal, and X2 is the second X-axis of the quartz crystal. In this example, X1, which is the first X-axis of the quartz crystal, is an axis parallel to the width direction of the tuning fork type quartz crystal resonator 10. The second X-axis X2 is an axis that is 120° symmetrical with respect to the first X-axis X1, with the Z-axis of the quartz being the center of rotation due to the trigonal crystal system of the quartz. The Y' and Z' axes are also axes that are shifted by a predetermined angle that depends on the well-known directional angle of the tuning fork type quartz crystal unit 10 with respect to the Y-axis and X-axis of the quartz crystal.

[0014] The tuning-fork-type quartz crystal resonator 10 of the first embodiment comprises a base 11, a first vibrating arm 13a and a second vibrating arm 13b extending parallel to each other from the base 11, a support arm 15 extending from the base between these vibrating arms, a first excitation electrode 17a and a second excitation electrode 17b arranged on the first and second vibrating arms, a first connection pad 17ax provided by drawing out wiring to the tip side of the support arm and a second connection pad 17bx provided on the base side of the support arm in order to connect the first excitation electrode and the second excitation electrode to the outside, and at least a pair of notches, a first notch 15a and a second notch 15b, provided on both sides along the width direction of the support arm in a region midway along the longitudinal direction of the support arm and between the first connection pad and the second connection pad. The first notch 15a is a notch that is parallel to the first X-axis X1 and terminates in the -X direction of this axis. The second notch 15b is a notch that is parallel to the second X-axis X2 and terminates in the -X direction of this axis. In this case, the second notch 15b is a notch that opens in a slightly oblique direction toward the tip side of the support arm 15. If the second notch 15b is open toward the tip side of the support arm, when developing the resist in the second notch 15b by photolithography technology or performing metal etching, the developer or metal etching can easily enter the inside of the notch, which is considered to be preferable for resist development and metal etching during metal film patterning. In the tuning fork crystal resonator 10 of the first embodiment, grooves 13c are provided on the front and back of each of the first vibrating arm 13a and the second vibrating arm 13b (see FIG. 1B). Although the grooves 13c are not essential, providing the grooves 13c increases the electric field efficiency in each vibrating arm compared to when the grooves 13c are not provided, making it easier to drive the tuning fork crystal resonator (reducing the crystal impedance).

[0015] Here, the cross section of the first notch 15a taken along line PP in Fig. 1(A) has a shape including an inclined surface 15aa that descends along the first X-axis X1 from the front and back of the support arm 15, as shown in Fig. 1(B). Also, the cross section of the second notch 15b taken along line QQ in Fig. 1(c) has a shape including an inclined surface 15ba that descends along the second X-axis X2 from the front and back of the support arm 15, as shown in Fig. 1(C). These inclined surfaces including inclined surface 15aa that descends toward the +X-axis and inclined surface including 15ba are well-known shapes that arise due to the etching anisotropy of the X-, Y-, and Z-axes of quartz, but the present invention is characterized in that the electrode is divided using the above-mentioned special inclined surfaces of the two X-axes that are generated symmetrically at 120°. By providing the notches 15a, 15b using the two X-axes in this manner, the wiring that is routed from the excitation electrodes 17a, 17b to the support arm 15 and reaches the first connection pad 17ax and the second connection pad 17bx can be reliably divided on the side surface of the support arm 15 by the inclined surface.

[0016] 2. Tuning fork type crystal resonator according to another embodiment Next, a tuning-fork type crystal resonator according to another embodiment will be described with reference to FIGS. First, the second embodiment will be described. Fig. 2(A) is a plan view for explaining a tuning-fork type crystal resonator 20 of the second embodiment. The tuning-fork type crystal resonator 20 of the second embodiment differs from the tuning-fork type crystal resonator 10 of the first embodiment in the configuration of the second notch. That is, in the tuning-fork type crystal resonator 10 of the first embodiment, the second notch 15b (see Fig. 1(A)) is provided parallel to the second X-axis located at a position 120 degrees symmetrical in the positive direction with respect to the first X-axis around the Z-axis as the center of rotation, and the -X direction of the axis is the terminal point, whereas in the case of the second embodiment, the second notch 15c (see Fig. 2(A)) is provided parallel to the third X-axis X3 located at a position 120 degrees symmetrical in the opposite direction to Fig. 2(A) around the Z-axis as the center of rotation, and the -X direction of the axis is the terminal point. In this case, the second cutout 15c is a cutout that opens toward the base side of the support arm 15, and actually opens in a slightly oblique direction. In the case of the tuning fork type crystal resonator 20 of the second embodiment, similarly to the first embodiment, it is possible to perform electrode division using two predetermined inclined surfaces along the +X axis.

[0017] Next, a third embodiment will be described. Fig. 2(B) is a plan view for explaining a tuning-fork type crystal resonator 30 of the third embodiment. The tuning-fork type crystal resonator 30 of the third embodiment differs from the tuning-fork type crystal resonator 10 of the first embodiment in that a third notch 15d is provided. That is, in the tuning-fork type crystal resonator 30 of the third embodiment, a third notch 15d is provided at the tip of the support arm 15, which is parallel to the second X-axis X2 and terminates in the -X direction of that axis. In the case of the tuning-fork type crystal resonator 30 of the third embodiment, the electrodes on the side surface of the supporting arm can be divided into three locations. In the case of the tuning-fork type crystal resonator 30 of the third embodiment, the tip of the supporting arm 15 is obliquely shaped with a contour perpendicular to the second X-axis X2. With such an oblique shape, it is easier to form the third notch 15d than if it were not so. Of course, the tuning-fork type crystal resonator 20 according to the second embodiment shown in FIG. 2(A) may be provided with the third notch 15d shown in FIG. 2(B).

[0018] In each of the above-mentioned embodiments, it is important that the width dimension W1 and depth dimension D1 of the first notch 15a, the width dimension W2, the first depth dimension D21 and the second depth dimension D22 of the second notch 15b, and the width dimension W3 and depth dimension D3 of the third notch 15d shown in Fig. 2(B) are determined to be appropriate width and depth dimensions that can form a predetermined crystal plane (inclined surface) at the end of the notch to properly divide the electrode and do not reduce the strength of the support arm. For example, when the width dimension of the support arm is defined as W0, each of W1, W2, W3, D1, D21, D22, and D3 can be selected from, for example, 0.1W0 to 0.4W0, preferably 0.15W0 to 0.35W0, and more preferably 0.15W0 to 0.30W0.

[0019] In particular, the depth dimensions of the second notch 15b are shown as D21 and D22 as shown in FIG. 2(B). In this case, the second notch 15b is obliquely intersected with the support arm 15, so that a first depth dimension D21 with a large depth and a second depth dimension D22 with a small depth are generated. Moreover, the depth dimension that has a large effect on generating a crystal plane in the second notch 15b is the second depth dimension D22 with a small depth dimension. That is, in the case of the present invention, if the second depth dimension D22 is too short for the second notch 15b, the desired crystal plane cannot be generated. Therefore, the dimension of the second depth dimension D22 is important for the second notch 15b. In this regard, an example of an element produced as a prototype of the tuning fork type crystal resonator 10 of the first embodiment will be described below.

[0020] 3A and 3B are scanning electron microscope (SEM) photographs of an element that is an actual prototype of the tuning-fork type quartz crystal resonator 10 of the first embodiment, focusing in particular on the support arm 15, the first notch 15a, and the second notch 15b. In particular, Fig. 3A is a planar photograph, Fig. 3B is a cross-sectional photograph taken along line RR in Fig. 3A, and Fig. 3C is a cross-sectional photograph taken along line SS in Fig. 3A. The inventors of this application made various prototypes by changing the width W2 of the second notch 15b and the second depth dimension D22 to multiple levels while setting the thickness of the tuning fork type quartz crystal unit to 100 μm. As a result, it was found that in order to form a desired crystal face at the end of the second notch 15b, the width W2 and the second depth dimension D22 of the second notch should be 10 μm or more, preferably 20 μm or more, and more preferably 25 μm or more. The upper limit of the depth dimension D22 is determined so that the strength of the support arm 15 is not reduced. Although not limited to this, in the case of the prototype element shown in FIG. 3, the width dimension W2 is 30 μm and the depth dimension D22 is 40 μm. In addition, in the case of this element, the width W0 of the support arm is 260 μm. The above conditions regarding the width W2 and the second depth dimension D22 of the second cutout 15b may also be applied to the case where the third cutout 15d is disposed obliquely with respect to the support arm 15.

[0021] It was also found that if the tuning fork crystal unit is too thin, it becomes difficult to leave inclined surfaces originating from the crystal plane at the ends of the first, second, and third notches. To avoid this, it was found that the thickness of the tuning fork crystal unit should be 50 μm or more, preferably 60 μm or more. However, if the tuning fork crystal unit is too thick, wet etching becomes difficult, so the upper limit of the thickness should be, for example, about 100 to 120 μm, which is used for commercially available tuning forks. In the embodiment, a pair of first notches 15a and second notches 15b are provided in support arm 15, but in addition to the pair of notches, one or more third notches may be provided midway along the longitudinal direction of the support arm, which are parallel to the first X-axis, second X-axis, or third X-axis and terminate in the -X direction of this axis. This makes it possible to more reliably perform electrode division.

[0022] 2. Examples of crystal devices The tuning fork type crystal resonator according to the present invention can be used as a tuning fork type crystal resonator for constituting various crystal devices including a crystal resonator and a crystal oscillator. As an example for deepening understanding, an example of a crystal device 50 using the tuning fork type crystal resonator 10 of the first embodiment will be described. Figure 4 is a diagram for this purpose, in particular Figure 4(A) is a plan view, Figure 4(B) is a cross-sectional view taken along line PP in Figure 4(A), and Figure 4(C) is a rear view. The crystal device 50 uses a ceramic container 51 having a recess 51a for accommodating the tuning fork crystal unit 10. A connection pad 51b on the container side is provided on the bottom surface of the recess 51a. An external mounting terminal 51c is provided on the outer bottom surface of the container 51. The connection pad 51b and the external mounting terminal 51c are connected by via wiring (not shown). The tuning fork type crystal unit 10 is connected and fixed to the container 51 at the positions of the first connection pad 17ax and the second connection pad 17bx of the support arm 15 and the connection pad 51b on the container side by a conductive adhesive 53. A lid member 55 is bonded to the top surface of the container 51, sealing the tuning fork type crystal unit 10 in the container 51. In the above description, a crystal device having a container 51 with a recess 51a is exemplified as a container, but the container is not limited to the above example and may be any suitable container.

[0023] 3. An example of a manufacturing method Next, in order to deepen understanding of the tuning-fork type crystal resonator of the present invention, an example of a method for manufacturing the tuning-fork type crystal resonator 10 of the first embodiment will be described. Figures 5(A) and (B) are explanatory diagrams for this purpose. In this manufacturing method example, first, as shown in Fig. 5(A), a large number of external shapes 10a of the tuning fork type quartz crystal resonators, each of which is composed of a base, first and second vibrating arms, and a supporting arm, are formed in a matrix on a quartz crystal wafer Wa. This can be performed by known film formation techniques, photolithography techniques, and wet etching techniques. Specifically, a metal film is formed on both main surfaces of a crystal wafer Wa, then a resist pattern is formed on the crystal wafer to cover the tuning fork outline 10a and the portions that will become the bars (not shown) that hold the outline of each tuning fork, and the metal film is selectively etched using the resist pattern as a mask. The crystal wafer is then immersed in a hydrofluoric acid-based etchant to obtain a wafer on which a large number of tuning fork pieces corresponding to the outline 10a are arranged in a matrix.

[0024] Next, as shown in FIG. 5B, an etching mask having a first notch forming opening 15ax for forming a first notch and a second notch forming opening 15bx for forming a second notch is formed on the crystal wafer Wa on which the outer shape 10a has been formed. Then, the crystal wafer is immersed in a hydrofluoric acid-based etchant. This step is preferably performed together with the step of forming the window 13cx for forming a groove in the vibrating arm, and is performed in this embodiment. After this etching step, a structure having the first notch 15a and the second notch 15b of the tuning fork type crystal resonator 10 of the first embodiment shown in FIG. 1 is obtained. After that, a metal film for forming the excitation electrodes is formed on the entire surface of the crystal wafer, and then the metal film is patterned to form the first excitation electrode, the second excitation electrode, and the first connection pad and the second connection pad. In this patterning process, the first connection pad and the second connection pad are electrically separated using the inclined surface generated on the predetermined +X side of the first notch and the second notch. The crystal wafer thus formed is an intermediate wafer for manufacturing the tuning fork type crystal unit 10. In addition, the tuning fork type crystal unit 10 is cut from this intermediate wafer and mounted in, for example, a container 51 shown in FIG. 4 to manufacture a piezoelectric device 50. [Explanation of symbols]

[0025] 10: tuning fork type crystal resonator according to the first embodiment 11: base 13a: First vibrating arm 13b: Second vibrating arm 13c: Groove 15: Support arm 15a: 1st notch 15aa: Inclined surface 15b: 2nd notch 15ba: Slanted surface 15c: Another example of the second notch 15d: Third notch 17a: First excitation electrode 17b: Second excitation electrode 17ax: 1st connection pad 17bx: 2nd connection pad X1: 1st X-axis X2: 2nd X-axis X3: 3rd X axis 50: Quartz crystal device Wa: Intermediate wafer

Claims

1. a tuning-fork type crystal resonator comprising: a base; first and second vibrating arms extending from the base in parallel to each other; a support arm extending from the base between the vibrating arms; a first excitation electrode and a second excitation electrode disposed on the first and second vibrating arms; a first connection pad provided on a tip side of the support arm and a second connection pad provided on a base side of the support arm for connecting the first excitation electrode and the second excitation electrode to an outside; and at least one pair of notches provided on both sides along a width direction of the support arm in a region midway in a longitudinal direction of the support arm and between the first connection pad and the second connection pad, When the X-axis of the quartz crystal parallel to the width direction of the tuning fork quartz crystal unit is defined as the first X-axis, and the X-axes 120 degrees symmetrical to the first X-axis due to the fact that the quartz crystal is a trigonal crystal system are defined as the second X-axis and the third X-axis, respectively, A first notch of the pair of notches is parallel to the first X-axis and terminates in a -X direction of the first X-axis; The tuning-fork type quartz crystal resonator is characterized in that the second notch of the pair of notches is a notch that is parallel to the second X-axis or the third X-axis and terminates in the -X direction of this axis.

2. 2. The tuning-fork type quartz crystal resonator according to claim 1, wherein each of the first notch and the second notch includes an inclined surface that slopes downward from the front and rear surfaces of the support arm toward a +X-axis direction of each notch.

3. 2. The tuning-fork type crystal resonator according to claim 1, wherein the second cutout is open at a tip end side of the supporting arm.

4. 2. The tuning-fork type crystal resonator according to claim 1, wherein the second cutout is open toward a base side of the supporting arm.

5. 2. The tuning-fork type quartz crystal resonator according to claim 1, wherein, when the width dimension of the first notch is defined as W1, the depth dimension thereof is defined as D1, the width dimension of the second notch is defined as W2, the first depth dimension is defined as D21, the second depth dimension is defined as D22, and the width dimension of the support arm is defined as W0, each of W1, D1, W2, D21, and D22 is the same or different dimensions selected from 0.1 W to 0.4 W (wherein the first depth dimension D21 and the second depth dimension D22 refer to the left and right depth dimensions of the second notch, and have a relationship of D21>D22).

6. When the width dimension of the second cutout is defined as W2, and the depth dimension of the shorter side of the left and right depth dimensions of the second cutout is defined as a second depth dimension D22, 2. The tuning-fork type crystal resonator according to claim 1, wherein the width dimension W2 and the second depth dimension D22 are the same or different and are selected from a range of 10 μm or more.

7. 2. The tuning-fork type quartz crystal resonator according to claim 1, wherein, when the thickness of the tuning-fork type quartz crystal resonator is defined as T, said T is 60 μm or more.

8. A quartz crystal device comprising: the tuning fork type quartz crystal resonator according to any one of claims 1 to 7; and a container in which the tuning fork type quartz crystal resonator is mounted.

9. 8. An intermediate wafer for manufacturing tuning-fork type quartz crystal resonators, comprising a large number of tuning-fork type quartz crystal resonators according to claim 1 arranged in a matrix.

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