Vibration element manufacturing method, quartz plate, and vibration element

Abstract

To provide a vibration element manufacturing method that can reduce variations of a breaking position in breaking off a vibration substrate.SOLUTION: A vibration element manufacturing method includes: performing wet etching on a quartz plate to form a vibration substrate, a frame part, and a connection part for connecting the vibration substrate to the frame part; and breaking off the vibration substrate at the connection part to cut off the vibration substrate from the frame part. Forming the vibration substrate, the frame part, and the connection part includes forming, in the connection part, a notch part that is a groove or a through hole along a width direction of the connection part. The notch part includes a first end on one side in the width direction, and a second end on the other side in the width direction. At least one of the first end and the second end has a first side facing the vibration substrate and a second side facing the frame part. The distance between the first side and the second side is gradually reduced as moving away from the center of the notch part in the width direction.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a vibration element, a quartz plate, and a vibration element. [Background technology]

[0002] Patent Document 1 discloses a method for manufacturing a vibration element, including the steps of etching a quartz substrate to form a quartz piece, a frame portion, and an arm portion as a connecting portion connecting the quartz piece and the frame portion, forming electrodes on the surface of the quartz piece, and mechanically breaking the arm portion to separate the quartz piece. In the method for manufacturing a vibration element disclosed in Patent Document 1, a first arm portion extending from the frame portion and a second arm portion narrower than the first arm portion are formed in the arm portion, and the second arm portion is broken in the step of separating the quartz piece. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-186847 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the method of manufacturing a vibration element disclosed in Patent Document 1, the breaking position of the second arm portion is prone to variation, and the shape of the remaining part of the arm portion that remains on the crystal piece after it is broken off also varies. [Means for solving the problem]

[0005] One aspect of the method for manufacturing a vibration element according to the present invention is to forming a vibration substrate, a frame portion, and a connecting portion that connects the vibration substrate to the frame portion by wet etching a quartz plate; Breaking off the vibration substrate at the connecting portion to separate the vibration substrate from the frame portion; Including, The formation of the vibration substrate, the frame portion, and the connecting portion includes: forming a notch portion, which is a groove or a through hole, in the connecting portion along a width direction of the connecting portion; The cutout portion includes a first end portion on one side in the width direction and a second end portion on the other side in the width direction, At least one of the first end and the second end is A first side is located on the vibration substrate side and a second side is located on the frame side, The distance between the first side and the second side gradually decreases with increasing distance from the center of the cutout portion in the width direction.

[0006] One aspect of the quartz crystal plate according to the present invention is A vibration substrate; A frame portion and A connecting portion that connects the vibration substrate to the frame portion; Including, The connecting portion has a notch portion, which is a groove or a through hole, formed along a width direction of the connecting portion, The cutout portion has a first end portion on one side in the width direction and a second end portion on the other side in the width direction. and At least one of the first end and the second end is A first side is located on the vibration substrate side and a second side is located on the frame side, The distance between the first side and the second side gradually decreases with increasing distance from the center of the cutout portion in the width direction.

[0007] One aspect of the vibration element according to the present invention is A quartz crystal substrate having the crystal axes of the quartz crystal as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and X-axis as the front and back principal surfaces; a recess provided on a side included in an outer edge of one main surface of the quartz crystal substrate; Including, The recessed portion is A first outer edge along the side; a second outer edge connected to one end of the first outer edge and inclined relative to the first outer edge; a third outer edge connected to the other end of the first outer edge and having an arcuate shape; Includes.

[0008] One aspect of the vibration element according to the present invention is A quartz crystal substrate having the crystal axes of the quartz crystal as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and X-axis as the front and back principal surfaces; a protrusion provided at an end of the quartz crystal substrate; Including, the protrusion has a first groove formed on one main surface of the quartz crystal substrate, the first groove includes a first surface and a second surface inclined with respect to the one main surface, The corner formed by the first surface and the second surface forms the bottom of the first groove. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a plan view illustrating a vibration element manufactured by the vibration element manufacturing method according to the first embodiment. [Diagram 2] FIG. 2 is a diagram for explaining an AT-cut quartz crystal substrate. [Diagram 3] 4 is a flowchart showing an example of a method for manufacturing the vibration element according to the first embodiment. [Figure 4] 3A to 3C are diagrams illustrating a manufacturing process of the vibration element. [Diagram 5] 3A to 3C are diagrams illustrating a manufacturing process of the vibration element. [Figure 6] 3A to 3C are diagrams illustrating a manufacturing process of the vibration element. [Figure 7] 3A to 3C are diagrams illustrating a manufacturing process of the vibration element. [Figure 8] 3A to 3C are diagrams illustrating a manufacturing process of the vibration element. [Figure 9] FIG. 4 is a plan view illustrating a first cutout portion. [Figure 10] Graph showing the miniaturization index Wi and the miniaturization index Li. [Figure 11] Graph showing the relationship between the angle θ1 and the bond compaction index Wi×Li. [Figure 12] 12 is a graph showing an enlarged view of the peak position of the graph shown in FIG. 11. [Figure 13] FIG. 4 is a cross-sectional view illustrating a first cutout portion. [Figure 14] A graph showing the miniaturization index Di and the miniaturization index Wi. [Figure 15] Graph showing the relationship between the angle θ4' and the bond miniaturization index Di×Wi. [Figure 16] 16 is a graph showing an enlarged view of the peak position of the graph shown in FIG. 15. [Figure 17] Scanning electron microscope image of the first notch. [Figure 18] 5A to 5C are cross-sectional views each showing a schematic manufacturing process of the vibration element. [Figure 19] 5A to 5C are cross-sectional views each showing a schematic manufacturing process of the vibration element. [Figure 20] 11A to 11C are cross-sectional views each showing a schematic diagram of a modified example of the manufacturing process of the vibration element. [Figure 21] 5A to 5C are cross-sectional views each showing a schematic manufacturing process of the vibration element. [Figure 22] FIG. 13 is a plan view illustrating a vibration element according to a fifth embodiment. [Figure 23] FIG. 4 is a plan view illustrating a first protrusion. [Figure 24] FIG. 4 is a cross-sectional view illustrating a first protrusion. [Diagram 25] FIG. 13 is a cross-sectional view illustrating a first protrusion of a vibration element according to a sixth embodiment. [Figure 26] FIG. 13 is a cross-sectional view illustrating a first protrusion of a vibration element according to a seventh embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, not all of the configurations described below are necessarily essential components of the present invention.

[0011] 1. First embodiment 1.1. Vibration element First, a vibration element manufactured by the vibration element manufacturing method according to the first embodiment will be described with reference to the drawings. Fig. 1 is a plan view showing a schematic example of a vibration element 100 manufactured by the vibration element manufacturing method according to the first embodiment.

[0012] As shown in FIG. 1, the vibration element 100 includes a vibration substrate 110, a first excitation electrode 120, and a second excitation electrode .

[0013] The vibrating substrate 110 is an AT-cut quartz substrate. That is, the vibrating substrate 110 is a quartz plate whose front and back principal surfaces are ±Y' planes including the Z' axis and the X axis, with the crystal axes of the quartz being the X-axis, Y-axis, and Z-axis, and the Y-axis and Z-axis being rotated counterclockwise around the X axis to become the Y' axis and Z' axis.

[0014] FIG. 2 is a diagram for explaining the AT-cut quartz crystal substrate 111. Piezoelectric materials such as quartz crystal are generally trigonal crystals and have crystal axes (X, Y, Z) as shown in FIG. 2. The X-axis is the electrical axis, the Y-axis is the mechanical axis, and the Z-axis is the optical axis. The quartz crystal substrate 111 is a flat plate of a so-called rotated Y-cut quartz crystal substrate cut out from a piezoelectric material along a plane obtained by rotating the XZ plane by an angle θ around the X-axis. The Y-axis and the Z-axis are also rotated θ around the X-axis to become the Y'-axis and the Z'-axis, respectively. The quartz crystal substrate 111 is a substrate whose main surface is a plane including the X-axis and the Z'-axis, and whose thickness is in the direction along the Y'-axis. Here, when θ=35°15′, the quartz crystal substrate 111 becomes an AT-cut quartz crystal substrate. Therefore, the quartz crystal substrate 111 can vibrate with the XZ' plane perpendicular to the Y'-axis as the main vibration, and the thickness-shear vibration is the main vibration.

[0015] The vibration substrate 110 has a thickness direction in the Y' direction, and has a rectangular shape with its long sides in the X direction and its short sides in the Z' direction when viewed from the Y' direction.

[0016] The first excitation electrode 120 is provided on the main surface of the vibration substrate 110 on the +Y' side. The second excitation electrode 130 is provided on the main surface of the vibration substrate 110 on the -Y' side. The first excitation electrode 120 and the second excitation electrode 130 overlap each other in a plan view from the Y' direction. The first excitation electrode 120 and the second excitation electrode 130 are formed by stacking a metal layer such as gold or silver on a base layer such as chromium or nickel. The first excitation electrode 120 and the second excitation electrode 130 are electrodes for applying a voltage to the vibration substrate 110.

[0017] The first excitation electrode 120 is connected to a first electrode pad 124 via a first extraction electrode 122. The second excitation electrode 130 is connected to a second electrode pad 134 via a second extraction electrode 132. is connected to

[0018] In the vibration element 100, the vibration substrate 110 can be vibrated in a thickness-shear vibration mode as a main vibration by applying a voltage to the vibration substrate 110 via the first excitation electrode 120 and the second excitation electrode 130. Although not shown, the vibration element 100 may be a mesa-type vibration element in which a peripheral portion and a vibration portion surrounded by the peripheral portion and thicker than the peripheral portion are formed on the vibration substrate 110.

[0019] 1.2. Manufacturing method Next, a method for manufacturing the vibration element according to the first embodiment will be described with reference to the drawings. Fig. 3 is a flowchart showing an example of the method for manufacturing the vibration element according to the first embodiment. Figs. 4 to 8 are diagrams that typically show the manufacturing process of the vibration element 100.

[0020] (1) Step S2: wet etching the quartz plate First, as shown in FIG. 4, a quartz plate 2 is wet-etched to form a plurality of vibration substrates 110, a frame portion 200, and first and second connecting portions 300 and 400 that connect each vibration substrate 110 to the frame portion 200.

[0021] Specifically, first, the quartz plate 2 is prepared. Next, the quartz plate 2 is patterned using photolithography and etching techniques. For example, a metal thin film made of Cr, Au, or the like is formed on the surface of the quartz plate 2 as a corrosion-resistant film, and the metal thin film is patterned by photolithography to form a mask. Next, the quartz plate 2 on which the mask is formed is wet-etched using an etching solution such as hydrofluoric acid or ammonium fluoride. This allows the formation of a quartz plate 2 including a plurality of vibration substrates 110, a frame portion 200, and a first connecting portion 300 and a second connecting portion 400 that connect each vibration substrate 110 to the frame portion 200. In the quartz plate 2, each of the plurality of vibration substrates 110 is connected to the frame portion 200 by the first connecting portion 300 and the second connecting portion 400, and the plurality of vibration substrates 110 are integrally formed with the frame portion 200.

[0022] In a plan view seen from the Y' direction, the first connecting part 300 is connected to the -Z' side of one side 112 of the vibrating substrate 110 that is aligned in the Z' direction, and the second connecting part 400 is connected to the +Z' side of the side 112 of the vibrating substrate 110. In a plan view seen from the Y' direction, the vibrating substrate 110 is a rectangle having four sides, and the side 112 is the -X side of the two short sides that are aligned in the Z' direction.

[0023] In step S2, as shown in FIG. 5, a first cutout 310 is formed in the first connecting portion 300 along the width direction of the first connecting portion 300, and a second cutout 410 is formed in the second connecting portion 400 along the width direction of the second connecting portion 400. The width direction of the first connecting portion 300 and the width direction of the second connecting portion 400 are along the Z' axis. The first cutout 310 and the second cutout 410 are grooves formed in the main surface 2a of the quartz plate 2. The first cutout 310 is formed to reduce the variation in the break position in the first connecting portion 300 when the vibration substrate 110 described later is broken off. The second cutout 410 is formed to reduce the variation in the break position in the second connecting portion 400 when the vibration substrate 110 described later is broken off.

[0024] Although not shown, a third cutout portion is formed in the first connecting portion 300 along the width direction of the first connecting portion 300, and a fourth cutout portion is formed in the second connecting portion 400 along the width direction of the second connecting portion 400, similarly on the main surface 2b of the quartz plate 2.

[0025] The first cutout portion 310, the second cutout portion 410, the third cutout portion, and the fourth cutout portion are, for example, 0 is formed by wet etching. Since the first cutout portion 310 has a small area on the main surface of the quartz plate 2, a groove is formed by half-etching when the vibration substrate 110 and the like are wet-etched. The second cutout portion 410, the third cutout portion, and the fourth cutout portion are also half-etched to form grooves in the same manner.

[0026] In step S2, the shape of the first cutout portion 310 can be controlled by adjusting the shape of the mask, the type of etching solution, the etching time, the etching rate, etc. The same applies to the second cutout portion 410, the third cutout portion, and the fourth cutout portion.

[0027] Note that the process of forming the vibration substrate 110 etc. by wet etching and the process of forming the first notch portion 310, the second notch portion 410, the third notch portion, and the fourth notch portion by wet etching may be separate. For example, after the outer shape of the vibration substrate 110 etc. is formed by wet etching, the first notch portion 310, the second notch portion 410, the third notch portion, and the fourth notch portion may be formed by wet etching.

[0028] Fig. 6 is a plan view that typically shows the first cutout portion 310. Fig. 7 is a cross-sectional view that typically shows the first cutout portion 310. Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 6.

[0029] As shown in Fig. 6, the first cutout portion 310 includes a first end portion 312 on one side in the width direction of the first connecting portion 300, and a second end portion 314 on the other side in the width direction of the first connecting portion 300. In the example shown in Fig. 6, the first end portion 312 is an end portion on the +Z' side of the first connecting portion 300, and the second end portion 314 is an end portion on the -Z' side of the first connecting portion 300. Although not shown, the first end portion 312 may be an end portion on the -Z' side of the first connecting portion 300, and the second end portion 314 may be an end portion on the +Z' side of the first connecting portion 300.

[0030] The first end 312 has a first side 3a on the vibration substrate 110 side and a second side 3b on the frame portion 200 side. In the example shown in Fig. 6, the first side 3a is the side on the +X side of the first end 312, and the second side 3b is the side on the -X side of the first end 312. The first side 3a and the second side 3b are sides that define the outline of the first end 312 on the main surface 2a.

[0031] The distance between the first side 3a and the second side 3b in the X direction gradually decreases as it moves away from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300. In the example shown in FIG. 6, the distance between the first side 3a and the second side 3b gradually decreases from the -Z' side to the +Z' side. The distance between the first side 3a and the second side 3b in the X direction can also be called the width W of the first cutout portion 310 at the first end 312. That is, the first end 312 has a tapered shape in which the width W gradually narrows from the -Z' side to the +Z' side. The tip of the first end 312 is, for example, rounded. The tip of the first end 312 may be pointed.

[0032] As shown in FIG. 6, the first cutout portion 310 has a first side 3a and a second side 3b constituting the first end portion 312, a third side 3c connected to the first side 3a, a fourth side 3d connected to the second side 3b, and a fifth side 3e constituting the second end portion 314 in a plan view seen from the Y' direction. The third side 3c is a side of the first cutout portion 310 on the vibration substrate 110 side, and the fourth side 3d is a side of the first cutout portion 310 on the frame portion 200 side. That is, the third side 3c is a side of the first cutout portion 310 on the +X side, and the fourth side 3d is a side of the first cutout portion 310 on the -X side. In the portion of the first cutout portion 310 constituted by the third side 3c and the fourth side 3d, the width W of the first cutout portion 310 is, for example, constant. The third side 3c and the fourth side 3d are, for example, parallel to each other.

[0033] Here, when the angle between the first side 3a and the second side 3b is θ1, by satisfying 22°≦θ1≦76°, the first cutout portion 310 can be made smaller in the width direction and the length direction. Furthermore, by satisfying 27°≦θ1≦65°, the first cutout portion 310 can be made even smaller in the width direction and the length direction. Furthermore, by satisfying 35°≦θ1≦52°, the first cutout portion 310 can be made even smaller in the width direction and the length direction. The reason for this will be explained in "1.3.1. Reducing the size of the first cutout portion (W, L)" below.

[0034] When the angle between the first side 3a and the third side 3c is θ2, θ2=180°-(θ1 / 2) is satisfied. Therefore, by satisfying 142°≦θ2≦169°, the first cutout portion 310 can be made smaller in the width direction and the length direction. Furthermore, by satisfying 147.5°≦θ2≦166.5°, the first cutout portion 310 can be made even smaller in the width direction and the length direction. Furthermore, by satisfying 154°≦θ2≦162.5°, the first cutout portion 310 can be made even smaller in the width direction and the length direction.

[0035] Similarly, when the angle between the second side 3b and the fourth side 3d is θ3, θ3=180°-(θ1 / 2) is satisfied. Therefore, by satisfying 142°≦θ3≦169°, the first cutout portion 310 can be made smaller in the width direction and the length direction. Furthermore, by satisfying 147.5°≦θ3≦166.5°, the first cutout portion 310 can be made even smaller in the width direction and the length direction. Furthermore, by satisfying 154°≦θ3≦162.5°, the first cutout portion 310 can be made even smaller in the width direction and the length direction.

[0036] The second end 314 has, for example, a fifth side 3e having an arc shape. One end of the fifth side 3e is connected to the third side 3c, and the other end of the fifth side 3e is connected to the fourth side 3d. In the illustrated example, the second end 314 has a shape different from that of the first end 312, but the second end 314 and the first end 312 may have the same shape. That is, the second end 314 may have a side on the vibration substrate 110 side and a side on the frame portion 200 side, and the distance between the two sides may be gradually reduced as it moves away from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300.

[0037] As shown in FIG. 7, the first cutout 310 is composed of a plurality of inclined surfaces having different inclination angles with respect to the main surface 2a. The first cutout 310 has a first inclined surface 4a and a second inclined surface 4b that intersect with each other. A corner portion 5 formed by the first inclined surface 4a and the second inclined surface 4b forms the bottom of the groove. As shown in FIG. 6, the corner portion 5 extends in the width direction of the first connecting portion 300, that is, in the Z' direction. In the example shown in FIG. 7, the first cutout 310 is composed of four inclined surfaces, but the number of inclined surfaces that constitute the first cutout 310 is not particularly limited, and the first cutout 310 may be composed of five or more inclined surfaces.

[0038] Here, when the angle between the first inclined surface 4a and the second inclined surface 4b is θ4, by satisfying 30°≦θ4≦121°, the first cutout portion 310 can be made smaller in the width direction and the depth direction. Furthermore, by satisfying 35°≦θ4≦112°, the first cutout portion 310 can be made even smaller in the width direction and the depth direction. Furthermore, by satisfying 43°≦θ4≦100°, the first cutout portion 310 can be made even smaller in the width direction and the depth direction. The reason for this will be explained in "1.3.2. Reducing the size of the first cutout portion (W, D)" described later.

[0039] The third cutout portion 320 has the same shape as the first cutout portion 310. That is, the third cutout portion 320 has an end portion on the +Z' side of the first connecting portion 300 and an end portion on the -Z' side of the first connecting portion 300, and the distance between the two sides constituting the end portion on the +Z' side gradually decreases with increasing distance from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300. Furthermore, the third cutout portion 320 is made up of a plurality of inclined surfaces having different inclination angles with respect to the main surface 2a, and has two inclined surfaces that form the bottom of the groove.

[0040] The second cutout portion 410 formed in the second connecting portion 400 has a shape similar to that of the first cutout portion 310 , and the fourth cutout portion has a shape similar to that of the third cutout portion 320 .

[0041] As described above, by wet etching the quartz plate 2, a quartz plate 2 can be manufactured which includes a plurality of vibration substrates 110, a frame portion 200, and a first connecting portion 300 and a second connecting portion 400 which connect each vibration substrate 110 to the frame portion 200, in which a first cutout portion 310 and a second cutout portion 410 are formed in the first connecting portion 300, and in which a second cutout portion 410 and a fourth cutout portion are formed in the second connecting portion 400.

[0042] (2) Step S4 of forming electrodes Next, an electrode material is deposited on the principal surface 2a and the principal surface 2b of the vibration substrate 110, and the deposited electrode material is patterned by photolithography. As a result, the first excitation electrode 120, the first extraction electrode 122, the first electrode pad 124, the second excitation electrode 130, the second extraction electrode 132, and the second electrode pad 134 can be formed on the vibration substrate 110.

[0043] (3) Process S6 of singulating the vibration substrate Next, the vibration substrate 110 is broken off at the first connecting portion 300 and the second connecting portion 400, thereby separating the vibration substrate 110 from the frame portion 200. Specifically, a suction nozzle is pressed against the vibration substrate 110. This breaks the first connecting portion 300 and the second connecting portion 400, allowing the vibration substrate 110 to be separated from the frame portion 200. The vibration substrate 110 separated from the frame portion 200 is supported by the suction nozzle.

[0044] Here, the first connecting portion 300 is formed with a first cutout portion 310, and the first end portion 312 of the first cutout portion 310 has a shape in which the distance between the first side 3a and the second side 3b gradually decreases as it moves away from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300. Therefore, when the vibration substrate 110 is broken off, stress is concentrated at the tip of the first end portion 312. That is, at the end of the first cutout portion 310 in the +Z' direction, the point where stress is concentrated is the tip of the first end portion 312. Therefore, as shown in FIG. 8, the first connecting portion 300 breaks at or near the broken line A that passes through the tip of the first end portion 312 and is parallel to the Z' axis. Therefore, the variation in the breakage position in the first connecting portion 300 can be reduced.

[0045] Furthermore, when the vibration substrate 110 is broken off, stress is concentrated at a corner 5 formed by the first inclined surface 4a and the second inclined surface 4b that form the bottom of the groove of the first cutout portion 310. Therefore, it is possible to reduce the variation in the breaking position in the first connecting portion 300. Furthermore, since the third cutout portion 320 has a similar shape to the first cutout portion 310, stress is concentrated at a similar position to the first cutout portion 310. Therefore, it is possible to reduce the variation in the breaking position in the first connecting portion 300.

[0046] In this manner, by forming the first cutout portion 310 and the third cutout portion 320 in the first connecting portion 300, the variation in the breaking position can be reduced.

[0047] Similarly to the first connecting portion 300, the second connecting portion 400 is also formed with the second cutout portion 410 and the fourth cutout portion, so that the variation in the breaking position can be reduced.

[0048] Through the above steps, the vibration element 100 can be manufactured.

[0049] 1.3. Calculation 1.3.1. Downsizing of the first cutout (W, L) 9 is a plan view showing a schematic diagram of the first cutout portion 310. As shown in FIG. 9, in the Z' direction, the distance between the end of the first side 3a on the -Z' side and the intersection P of the extension line of the first side 3a and the extension line of the second side 3b is defined as L1. In addition, in the X direction, the distance between the third side 3c and the fourth side 3d is defined as W1. The distance L1 corresponds to the length of the first end portion 312, and the distance W1 corresponds to the width W of the first cutout portion 310.

[0050] First, the distance L1 was fixed, and the relationship between the angle θ1 and the distance W1 was obtained, and a miniaturization index Wi was obtained as an index representing the effect of miniaturization in the width direction of the first cutout portion 310, i.e., in the X direction. Furthermore, the distance W1 was fixed, and the relationship between the angle θ1 and the distance L1 was obtained, and a miniaturization index Li was obtained as an index representing the effect of miniaturization in the length direction of the first cutout portion 310, i.e., in the Z' direction.

[0051] Here, the miniaturization index Wi is expressed as Wi = (Wmax - W1) / Wmax. Wmax is the maximum distance W1 that the first cutout portion 310 can have. The maximum distance Wmax can be set to any value. The larger the miniaturization index Wi, the greater the effect of miniaturization. Moreover, the miniaturization index Li is expressed as Li = (Lmax - L1) / Lmax. Lmax is the maximum distance L1 that the first cutout portion 310 can have. The maximum distance Lmax can be set to any value. The larger the miniaturization index Li, the greater the effect of miniaturization.

[0052] Fig. 10 is a graph showing the miniaturization index Wi and the miniaturization index Li. The horizontal axis of the graph shown in Fig. 10 is the angle θ1, and the vertical axis is the miniaturization index.

[0053] Next, the miniaturization index Wi and the miniaturization index Li were multiplied together and corrected to a maximum value of 1.0. This value was taken as the joint miniaturization index Wi×Li, and the relationship with the angle θ1 was determined. The larger the joint miniaturization index Wi×Li, the more the first cutout portion 310 can be made smaller.

[0054] Fig. 11 is a graph showing the relationship between the angle θ1 and the bond miniaturization index Wi×Li. The graph shown in Fig. 11 shows the relationship between the angle θ1 and the bond miniaturization index Wi×Li, with the horizontal axis representing the angle θ1 and the vertical axis representing the bond miniaturization index Wi×Li. Fig. 12 is a graph in which the peak positions of the graph shown in Fig. 11 are enlarged.

[0055] 12, when 22°≦θ1≦76°, the coupling miniaturization index Wi×Li is 0.90 or more, and it is understood that the first cutout portion 310 can be miniaturized in the width direction and the length direction. Also, when 27°≦θ1≦65°, the coupling miniaturization index Wi×Li is 0.95 or more, and it is understood that the first cutout portion 310 can be further miniaturized in the width direction and the length direction. Also, when 35°≦θ1≦52°, the coupling miniaturization index Wi×Li is 0.99 or more, and it is understood that the first cutout portion 310 can be further miniaturized in the width direction and the length direction.

[0056] 1.3.2. Downsizing of the first cutout (W, D) Fig. 13 is a cross-sectional view showing the first cutout portion 310. As shown in Fig. 13, in the X direction, the distance between the third side 3c and the fourth side 3d is W1, the height of an isosceles triangle with the straight line connecting the third side 3c and the fourth side 3d as the base is D1, and the angle of the apex is θ4'. In Fig. 13, an isosceles triangle with the base W1 and the height D1 is shown by a broken line. The height D1 corresponds to the depth D of the first cutout portion 310, and the angle θ4' corresponds to the angle θ4 between the first inclined surface 4a and the second inclined surface 4b.

[0057] First, the distance W1 was fixed, and the relationship between the angle θ4' and the height D1 was obtained, and a miniaturization index Di was obtained as an index representing the effect of miniaturization in the depth direction of the first cutout portion 310, i.e., in the Y' direction. Furthermore, the height D1 was fixed, and the relationship between the angle θ1 and the distance W1 was obtained, and a miniaturization index Wi was obtained as an index representing the effect of miniaturization in the width direction of the first cutout portion 310, i.e., in the X direction.

[0058] Here, the miniaturization index Di is expressed as Di=(Dmax-D1) / Dmax. Here, Dmax is the maximum depth that the first cutout portion 310 can have. The maximum depth Dmax can be set to any value. The larger the miniaturization index Di, the greater the effect of miniaturization. The miniaturization index Wi is expressed as Wi=(Wmax-W1) / Wmax, and the larger the miniaturization index Wi, the greater the effect of miniaturization.

[0059] Fig. 14 is a graph showing the miniaturization index Di and the miniaturization index Wi. The horizontal axis of the graph shown in Fig. 14 is the angle θ4', and the vertical axis is the miniaturization index.

[0060] Next, the miniaturization index Di and the miniaturization index Wi were multiplied together and corrected to a maximum value of 1.0. This value was taken as the joint miniaturization index Di×Wi, and the relationship with the angle θ4′ was obtained. The larger the joint miniaturization index Di×Wi, the more the first cutout portion 310 can be made small.

[0061] Fig. 15 is a graph showing the relationship between the angle θ4' and the bond compaction index Di×Wi. The graph shown in Fig. 15 shows the relationship between the angle θ4' and the bond compaction index Di×Wi, with the horizontal axis representing the angle θ4' and the vertical axis representing the bond compaction index Di×Wi. Fig. 16 is a graph in which the peak positions of the graph shown in Fig. 15 are enlarged.

[0062] 16, when 30°≦θ4′≦121°, the coupling miniaturization index Di×Wi is 0.85 or more, and it is understood that the first cutout portion 310 can be miniaturized in the depth direction and the width direction. Also, when 35°≦θ4′≦112°, the coupling miniaturization index Di×Wi is 0.90 or more, and it is understood that the first cutout portion 310 can be further miniaturized in the depth direction and the width direction. Also, when 43°≦θ4′≦100°, the coupling miniaturization index Di×Wi is 0.95 or more, and it is understood that the first cutout portion 310 can be further miniaturized in the depth direction and the width direction.

[0063] 1.4. Effects The method for manufacturing the vibration element according to the first embodiment includes a step S2 of forming the vibration substrate 110, the frame portion 200, and the first connecting portion 300 and the second connecting portion 400 that connect the vibration substrate 110 to the frame portion 200 by wet etching the quartz plate 2, and a step S6 of separating the vibration substrate 110 from the frame portion 200 by breaking off the vibration substrate 110 at the first connecting portion 300 and the second connecting portion 400. The step S2 also includes a step of forming a first cutout portion 310, which is a groove along the width direction of the first connecting portion 300, in the first connecting portion 300. The first cutout portion 310 also includes a first end portion 312 on one side of the first connecting portion 300 in the width direction and a second end portion 314 on the other side of the first connecting portion 300 in the width direction. In addition, at least one of the first end 312 and the second end 314 has a first side 3a on the vibration substrate 110 side and a second side 3b on the frame portion 200 side, and the distance between the first side 3a and the second side 3b gradually decreases as it moves away from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300.

[0064] Thus, the first cutout portion 310 has a first end portion 312 in which the distance between the first side 3a and the second side 3b gradually decreases as it moves away from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300. Therefore, when the vibration substrate 110 is broken off, stress is concentrated at the tip of the first end portion 312. Therefore, in the manufacturing method of the vibration element according to the first embodiment, it is possible to reduce the variation in the breakage position, and the first end portion 312 remaining in the vibration element 100 after breaking off can be reduced. This reduces variation in the shape of the remaining portion of the connecting portion 300.

[0065] In the method for manufacturing a vibration element according to the first embodiment, when the angle between the first side 3a and the second side 3b is θ1, the relationship 22°≦θ1≦76° is satisfied. Therefore, in the method for manufacturing a vibration element according to the first embodiment, the first cutout portion 310 can be made smaller in the width direction and the length direction. Therefore, in the method for manufacturing a vibration element according to the first embodiment, the variation in the breakage position can be reduced even when manufacturing a small vibration element.

[0066] The method for manufacturing a vibration element according to the first embodiment satisfies 27°≦θ1≦65°. Therefore, the method for manufacturing a vibration element according to the first embodiment can reduce the size of the first cutout portion 310 in the width direction and the length direction. Therefore, the method for manufacturing a vibration element according to the first embodiment can reduce the variation in the breakage position even when manufacturing a smaller vibration element.

[0067] The method for manufacturing a vibration element according to the first embodiment satisfies 35°≦θ1≦52°. Therefore, the method for manufacturing a vibration element according to the first embodiment can further reduce the size of the first cutout portion 310 in the width direction and the length direction. Therefore, the method for manufacturing a vibration element according to the first embodiment can reduce variation in the breakage position even when manufacturing even smaller vibration elements.

[0068] In the manufacturing method of the vibration element according to the first embodiment, the first cutout portion 310 has a third side 3c connected to the first side 3a and a fourth side 3d connected to the second side 3b, and when the angle between the third side 3c and the first side 3a is θ2, the angle satisfies 142°≦θ2≦169°, and when the angle between the fourth side 3d and the second side 3b is θ3, the angle satisfies 142°≦θ3≦169°. When the angles θ2 and θ3 satisfy 142°≦θ2≦169°, the angle θ1 satisfies 22°≦θ1≦76°. Therefore, in the manufacturing method of the vibration element according to the first embodiment, the first cutout portion 310 can be made smaller in the width direction and the length direction.

[0069] In the method for manufacturing the vibration element according to the first embodiment, the first cutout portion 310 is a groove, which can reduce the possibility that the vibration element 100 falls off the frame portion 200 during the manufacturing process.

[0070] In the manufacturing method of the vibration element according to the first embodiment, the first cutout portion 310 includes a first inclined surface 4a and a second inclined surface 4b that are two inclined surfaces intersecting each other, and a corner portion 5 formed by the first inclined surface 4a and the second inclined surface 4b forms the bottom of the groove. In addition, when the angle between the first inclined surface 4a and the second inclined surface 4b is θ4, 30°≦θ4≦121° is satisfied. Therefore, in the manufacturing method of the vibration element according to the first embodiment, the first cutout portion 310 can be made small in the depth direction and the width direction. Therefore, in the manufacturing method of the vibration element according to the first embodiment, even when a small vibration element is manufactured using a thin vibration substrate 110, the variation in the breakage position can be reduced.

[0071] In the method for manufacturing a vibration element according to the first embodiment, 35°≦θ4≦112° is satisfied. Therefore, in the method for manufacturing a vibration element according to the first embodiment, the first cutout portion 310 can be made smaller in the depth direction and width direction. Therefore, in the method for manufacturing a vibration element according to the first embodiment, even when a small vibration element is manufactured using a thinner vibration substrate 110, the variation in the breakage position can be reduced.

[0072] In the method for manufacturing a vibration element according to the first embodiment, 43°≦θ4≦100° is satisfied. Therefore, in the method for manufacturing a vibration element according to the first embodiment, the first cutout portion 310 can be made even smaller in the depth direction and width direction. Therefore, in the method for manufacturing a vibration element according to the first embodiment, even in the case of manufacturing a small vibration element using a thinner vibration substrate 110, , the variation in the fracture position can be reduced.

[0073] In the manufacturing method of the vibration element according to the first embodiment, the quartz plate 2 is a quartz plate having the crystal axes of the quartz as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and the ±Y' planes including the Z'-axis and the X-axis as the front and back principal surfaces. In addition, the process of forming the vibration substrate 110, the frame portion 200, the first connecting portion 300, and the second connecting portion 400 includes a process of forming, as the connecting portion, the first connecting portion 300 connected to the -Z' side of one side along the Z' direction of the vibration substrate 110, and the second connecting portion 400 connected to the +Z' side of the one side, and the distance between the first side 3a and the second side 3b gradually decreases from the -Z' side toward the +Z' side. In this way, in the manufacturing method of the vibration element according to the first embodiment, even when the quartz plate 2 is an AT-cut quartz substrate, the variation in the breakage position can be reduced.

[0074] The quartz crystal plate 2 includes a vibration substrate 110, a frame portion 200, and a first connecting portion 300 and a second connecting portion 400 that connect the vibration substrate 110 to the frame portion 200. The first connecting portion 300 includes a first cutout portion 310 that is a groove along the width direction of the first connecting portion 300, and the first cutout portion 310 includes a first end portion 312 on one side of the first connecting portion 300 in the width direction and a second end portion 314 on the other side of the first connecting portion 300 in the width direction. At least one of the first end portion 312 and the second end portion 314 includes a first side 3a on the vibration substrate 110 side and a second side 3b on the frame portion 200 side, and the distance between the first side 3a and the second side 3b gradually decreases as it moves away from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300.

[0075] Thus, the first cutout portion 310 has a first end portion 312 in which the distance between the first side 3a and the second side 3b gradually decreases with increasing distance from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300. Therefore, when the vibration substrate 110 is broken off, stress is concentrated at the tip of the first end portion 312. Therefore, in the quartz plate 2, the variation in the breakage position can be reduced, and the variation in the shape of the remaining portion of the first connecting portion 300 that remains on the vibration element 100 after being broken off can be reduced.

[0076] Fig. 17 is a scanning electron microscope image of the first cutout portion 310. As shown in Fig. 17, by wet etching the quartz crystal plate 2, a first cutout portion can be formed in which the distance between the first side 3a and the second side 3b at the end portion is gradually reduced with increasing distance from the center O of the first cutout portion 310 in the width direction of the first connecting portion 300.

[0077] 2. Second embodiment Next, a method for manufacturing a vibration element according to a second embodiment will be described with reference to the drawings. Fig. 18 is a cross-sectional view that shows a schematic diagram of a manufacturing process of the vibration element 100. Hereinafter, in the method for manufacturing a vibration element according to the second embodiment, detailed description of the same points as in the method for manufacturing a vibration element according to the first embodiment will be omitted.

[0078] 18, in the method for manufacturing the vibration element according to the second embodiment, in step S2 of etching the quartz plate 2, a first groove 316 is formed that connects the first end 312 of the first cutout portion 310 and the sidewall 302 on the +Z' side of the first connecting portion 300. In addition, in step S2 of etching the quartz plate 2, a second groove 318 is formed that connects the second end 314 of the first cutout portion 310 and the sidewall 304 on the -Z' side of the first connecting portion 300.

[0079] The first groove 316 connects the side wall 302 of the first connecting portion 300 and the tip of the first end 312 of the first cutout portion 310. The width of the first groove 316 is smaller than the width of the first cutout portion 310. The depth of the first groove 316 is smaller than the depth of the first cutout portion 310.

[0080] The second groove 318 is formed between the side wall 304 of the first connecting portion 300 and the second end of the first cutout portion 310. The second groove 318 connects the tip of the first cutout portion 310 to the tip of the second groove 314. The width of the second groove 318 is smaller than the width of the first cutout portion 310. The depth of the second groove 318 is smaller than the depth of the first cutout portion 310.

[0081] The first groove 316 and the second groove 318 can be formed by wet etching the quartz crystal plate 2. For example, when the vibration element 100 is a mesa-type vibration element in which a peripheral portion and a vibration portion surrounded by the peripheral portion and thicker than the peripheral portion are formed on the vibration substrate 110, the first groove 316 and the second groove 318 may be formed during etching to form the vibration portion. This can simplify the manufacturing process. The depth of the first groove 316 and the depth of the second groove 318 may be the same as the height of the vibration portion.

[0082] Although not shown, the third cutout portion 320 is also provided with a groove connecting an end portion of the third cutout portion 320 and a side wall of the first connecting portion 300, similar to the first cutout portion 310. The configuration of the second connecting portion 400 is similar to the configuration of the first connecting portion 300, and therefore a description thereof will be omitted.

[0083] In the manufacturing method of the vibration element according to the second embodiment, in the process S2 of etching the quartz plate 2, the first groove 316 and the second groove 318 are formed in the first connecting portion 300, so that the variation in the breakage position can be reduced compared to, for example, a case where the first groove 316 and the second groove 318 are not formed.

[0084] 3. Third embodiment Next, a method for manufacturing a vibration element according to a third embodiment will be described with reference to the drawings. Fig. 19 is a cross-sectional view that shows a schematic diagram of a manufacturing process of the vibration element 100. Hereinafter, in the method for manufacturing a vibration element according to the third embodiment, detailed description of the same points as in the method for manufacturing a vibration element according to the first embodiment will be omitted.

[0085] In the manufacturing method of the vibration element according to the first embodiment described above, in the process S2 of etching the quartz plate 2, a first cutout portion 310 is formed on the main surface 2a of the quartz plate 2, and a third cutout portion 320 is formed on the main surface 2b of the quartz plate 2, as shown in FIG. 7.

[0086] In contrast, in the manufacturing method of the vibration element of the third embodiment, in process S2 of etching the quartz plate 2, as shown in FIG. 19, a first cutout portion 310 is formed on the main surface 2a of the quartz plate 2, and no cutout portion is formed on the main surface 2b of the quartz plate 2.

[0087] In the method for manufacturing a vibration element according to the third embodiment, the first cutout portion 310 is formed in the main surface 2a of the quartz plate 2, thereby reducing the variation in the fracture position. Although not shown, the cutout portion may be formed in the main surface 2b of the quartz plate 2 without being formed in the main surface 2a of the quartz plate 2. Even when the cutout portion is formed in the main surface 2b of the quartz plate 2, the variation in the fracture position can be reduced.

[0088] 20 is a cross-sectional view that typically illustrates a modified example of the manufacturing process of the vibration element 100. In the manufacturing method of the vibration element according to the first embodiment described above, the first cutout portion 310 is a groove with a bottom, as illustrated in FIG.

[0089] 20, the first cutout 310 may be a through-hole penetrating the quartz crystal plate 2. Even when the first cutout 310 is a hole penetrating the quartz crystal plate 2, stress is concentrated at the tip of the first end 312 of the first cutout 310, so that the variation in the fracture position can be reduced.

[0090] 4. Fourth embodiment Next, a method for manufacturing a vibration element according to a fourth embodiment will be described with reference to the drawings. 21A to 21C are cross-sectional views that diagrammatically show the manufacturing process of the vibration element 100. Hereinafter, in the manufacturing method of the vibration element according to the fourth embodiment, detailed description of the same points as in the manufacturing method of the vibration element according to the first embodiment will be omitted.

[0091] 21, the tip of the first end 312 of the first cutout portion 310 is in contact with the side wall 302 of the first connecting portion 300. This can further reduce the variation in the breaking position.

[0092] Although not shown, the tip of the second end 314 may be in contact with the side wall 304 of the first connecting portion 300.

[0093] 5. Modifications The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the present invention.

[0094] In the above-mentioned first to fourth embodiments, the quartz crystal plate 2 has been described as an AT-cut quartz crystal substrate, but the quartz crystal plate 2 may be another type of quartz crystal substrate. For example, the quartz crystal plate 2 may be a Z-plate. A Z-plate is a quartz crystal substrate that is cut along a plane defined by the X-axis and the Y'-axis and processed into a flat plate shape, and has a predetermined thickness in the Z' direction perpendicular to the plane.

[0095] Furthermore, in the above-described first to fourth embodiments, the vibration substrate 110 is connected to the frame portion 200 by the first connecting portion 300 and the second connecting portion 400, but the vibration substrate 110 may be connected to the frame portion 200 only by the first connecting portion 300, or only by the second connecting portion 400.

[0096] 6. Fifth embodiment 6.1. Vibration element Next, a vibration element according to a fifth embodiment will be described with reference to the drawings. Fig. 22 is a plan view that shows a vibration element 500 according to the fifth embodiment. Hereinafter, in the vibration element 500 according to the fifth embodiment, members having the same functions as those of the vibration element 100 shown in Fig. 1 and the quartz plate 2 shown in Figs. 4 to 7 are given the same reference numerals, and detailed description thereof will be omitted.

[0097] The vibration element 500 is an example of a vibration element manufactured by the vibration element manufacturing method according to the first embodiment described above. The vibration element 500 includes a vibration substrate 110, a first excitation electrode 120, and a second excitation electrode 130. The vibration substrate 110 is a quartz substrate in which the crystal axes of quartz are the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis are rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and ±Y' planes including the Z'-axis and X-axis are the front and back principal surfaces.

[0098] A first protrusion 510 and a second protrusion 520 are provided at an end of the vibration substrate 110. The first protrusion 510 is a remaining portion of the first connecting portion 300 shown in FIG. 5. The second protrusion 520 is a remaining portion of the second connecting portion 400 shown in FIG.

[0099] The first protrusion 510 and the second protrusion 520 are provided at the end of the vibration substrate 110 on the -X side. The first protrusion 510 and the second protrusion 520 are portions of the vibration substrate 110 that protrude in the -X direction. The first protrusion 510 is provided on the -Z' side of the vibration substrate 110, and the second protrusion 520 is provided on the +Z' side of the vibration substrate 110. In a plan view seen from the Y' direction, the first protrusion 510 is connected to the -Z' side of one side of the vibration substrate 110 that is aligned in the Z' direction. The second protrusion 520 is connected to the +Z' side of one side of the vibration substrate 110 that is aligned in the Z' direction. The vibration substrate 110 is shaped like a rectangle having a long side aligned along the X axis and a short side aligned along the Z' direction. The first protrusion 510 and the second protrusion 520 The first protrusion 510 and the second protrusion 520 are provided on the short side of the vibration substrate 110 on the -X side.

[0100] Fig. 23 is a plan view that typically illustrates the first protrusion 510. Note that Fig. 23 illustrates the first protrusion 510 as viewed from the Y' direction.

[0101] The first protrusion 510 includes a first recess 6 provided on a side 6d included in the outer edge of one main surface 2a of the vibration substrate 110. The side 6d is along the Z' axis. The side 6d is a side formed by breaking the first connection portion 300.

[0102] The first recess 6 includes a first outer edge 6a, a second outer edge 6b, and a third outer edge 6c. The first outer edge 6a, the second outer edge 6b, and the third outer edge 6c are sides included in the outer edge of the main surface 2a. The first outer edge 6a, the second outer edge 6b, and the third outer edge 6c form the outer edge of the main surface 2a of the vibration substrate 110 on the -X side.

[0103] The first outer edge 6a is along the side 6d. The first outer edge 6a is along the Z' axis. The first outer edge 6a is located on the +X side of the side 6d. The first outer edge 6a forms the bottom of the first recess 6. The first outer edge 6a is linear. The first outer edge 6a corresponds to the third side 3c of the first cutout portion 310 shown in FIG. 6.

[0104] The second outer edge 6b is connected to one end of the first outer edge 6a. The second outer edge 6b is connected to the end of the first outer edge 6a on the +Z' side. The end of the second outer edge 6b on the -Z' side is connected to the first outer edge 6a, and the end of the second outer edge 6b on the +Z' side is connected to the side 6d. The second outer edge 6b is inclined with respect to the first outer edge 6a. The second outer edge 6b is inclined with respect to the Z' axis. The second outer edge 6b is linear. The second outer edge 6b corresponds to the first side 3a of the first cutout portion 310 shown in FIG. 6.

[0105] The third outer edge 6c is connected to the other end of the first outer edge 6a. The third outer edge 6c is connected to the end of the first outer edge 6a on the -Z' side. The end of the third outer edge 6c on the -Z' side is connected to the side 6d, and the end of the third outer edge 6c on the +Z' side is connected to the first outer edge 6a. The third outer edge 6c is arc-shaped. The third outer edge 6c corresponds to the fifth side 3e of the first cutout portion 310 shown in FIG. 6.

[0106] Angle θ between the first outer edge 6a and the second outer edge 6b A corresponds to the angle θ2. Therefore, the angle θ A 142°≦θ A ≦169°. Also, the angle θ A 147.5°≦θA ≦166.5° or 154°≦θ A ≦162.5° may be satisfied.

[0107] The second protrusion 520 shown in Fig. 22 has a similar shape to the first protrusion 510 shown in Fig. 23. That is, the second protrusion 520 includes a second recess 7 provided on a side included in the outer edge of the main surface 2a of the vibration substrate 110. The second recess 7 has a similar shape to the first recess 6. The first recess 6 is provided on the -Z' side of the vibration substrate 110, and the second recess 7 is provided on the +Z' side of the vibration substrate 110.

[0108] Fig. 24 is a cross-sectional view that diagrammatically shows the first protrusion 510. Fig. 24 is a cross-sectional view taken along line XXIV-XXIV in Fig. 23.

[0109] 24, the first protruding portion 510 includes a first groove 512. The first groove 512 is formed in one main surface 2a of the vibration substrate 110. The first groove 512 corresponds to the first cutout portion 310 of the first connecting portion 300.

[0110] The first groove 512 includes a first surface 8a and a second surface 8b. The first surface 8a and the second surface 8b are inclined with respect to the main surface 2a. The first surface 8a and the second surface 8b intersect with each other. A corner 5a formed by the first surface 8a and the second surface 8b forms the bottom of the first groove 512.

[0111] The first surface 8a corresponds to the first inclined surface 4a of the first cutout portion 310 shown in Fig. 7. The second surface 8b corresponds to the second inclined surface 4b of the first cutout portion 310 shown in Fig. 7. The second surface 8b is a part of the second inclined surface 4b. The corner 5a formed by the first surface 8a and the second surface 8b corresponds to the corner 5 formed by the first inclined surface 4a and the second inclined surface 4b.

[0112] The angle between the first surface 8a and the second surface 8b is θ B corresponds to the angle θ4 between the first inclined surface 4a and the second inclined surface 4b. Therefore, the angle θ B 30°≦θ B≦121°. Also, the angle θ B 35°≦θ B ≦112° or 43°≦θ B ≦100° may be satisfied.

[0113] The first inclined surface 4a and the second inclined surface 4b are wet-etched surfaces formed by half-etching the quartz plate 2 in the above-mentioned step S2 of wet-etching the quartz plate 2. Therefore, the first surface 8a and the second surface 8b are wet-etched surfaces.

[0114] The first protruding portion 510 includes a third surface 8c that is inclined with respect to the main surface 2a. The third surface 8c is connected to the second surface 8b, and a corner 9 formed by the second surface 8b and the third surface 8c constitutes the tip of the first protruding portion 510. The tip of the first protruding portion 510 is a portion of the first protruding portion 510 that is located closest to the -X side. The third surface 8c is a fracture surface formed by breaking the first connecting portion 300 in the step S6 of dividing the vibration substrate 110 into individual pieces.

[0115] The first protrusion 510 includes an inclined portion 513 as shown in FIG. 24. The inclined portion 513 is formed on the other main surface 2b of the vibration substrate 110. The inclined portion 513 is composed of a plurality of inclined surfaces inclined with respect to the main surface 2b. The inclined portion 513 connects the main surface 2b and the third surface 8c. The inclined portion 513 is composed of a part of a plurality of inclined surfaces constituting the third cutout portion 320. In the illustrated example, the inclined portion 513 corresponds to two inclined surfaces located on the +X side from the bottom of the groove of the third cutout portion 320 among the plurality of inclined surfaces constituting the third cutout portion 320 shown in FIG. 7.

[0116] 6.2. Manufacturing method The method for manufacturing the vibration element 500 is similar to the method for manufacturing the vibration element according to the first embodiment described above, and therefore the description thereof will be omitted.

[0117] Effects The vibration element 500 includes a vibration substrate 110 made of a quartz substrate having crystal axes of quartz as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis being rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and the X-axis as the front and back principal surfaces, and a first recess 6 provided on a side 6d included in the outer edge of one principal surface 2a of the vibration substrate 110. The first recess 6 also includes a first outer edge 6a along the side 6d, a second outer edge 6b connected to one end of the first outer edge 6a and inclined with respect to the first outer edge 6a, and a third outer edge 6c connected to the other end of the first outer edge 6a and having an arc shape.

[0118] In this way, in the vibration element 500, the first recess 6 is provided on the side 6d included in the outer edge of the vibration substrate 110, so that the bonding strength can be improved when the vibration element 500 is mounted on a mounting substrate using a bonding material such as a conductive adhesive or solder. By forming the recess, the contact area with the bonding member can be made larger than when there is no recess on the side 6d, and therefore the bonding strength when mounted on a mounting board can be improved.

[0119] In the vibration element 500, the first outer edge 6a is aligned along the Z' axis, the second outer edge 6b is connected to the end of the first outer edge 6a on the +Z' side, and the third outer edge 6c is connected to the end of the first outer edge 6a on the -Z' side. Therefore, in the vibration element 500, the bonding strength when mounted on a mounting board can be improved compared to when the edge 6d does not have a recess.

[0120] In the vibration element 500, the angle between the first outer edge 6a and the second outer edge 6b is θ A In this case, 142°≦θ A ≦169°. Therefore, in the vibration element 500, the first cutout portion 310 can be made smaller, and therefore the first connecting portion 300 can be made smaller. Therefore, in the vibration element 500, the first protruding portion 510, which is the remaining portion of the first connecting portion 300 that remains in the vibration element 500 after being broken off, can be made smaller, and a vibration element with less variation in characteristics can be realized.

[0121] The vibration element 500 includes, as recesses, a first recess 6 provided on the -Z' side of the vibration substrate 110 and a second recess 7 provided on the +Z' side of the vibration substrate 110. Therefore, the vibration element 500 can improve the bonding strength when mounted on a mounting substrate, compared to a case where there is only one recess.

[0122] The vibration element 500 includes a vibration substrate 110 made of a quartz substrate having the crystal axes of quartz as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and the X-axis as the front and back principal surfaces, and a first protrusion 510 provided at an end of the vibration substrate 110. The first protrusion 510 has a first groove 512 formed in one principal surface 2a of the vibration substrate 110, the first groove 512 including a first surface 8a and a second surface 8b inclined with respect to the principal surface 2a, and a corner 5a formed by the first surface 8a and the second surface 8b forms the bottom of the first groove 512.

[0123] In this way, in the vibration element 500, since the first protrusion 510 has the first groove 512, it is possible to improve the bonding strength when the vibration element 500 is mounted on a mounting substrate. Since the first protrusion 510 has the first groove 512, it is possible to increase the contact area with the bonding member compared to a case where the first protrusion 510 does not have a groove. In addition, an anchor effect is obtained by the bonding member entering the first groove 512. Therefore, in the vibration element 500, it is possible to improve the bonding strength when the vibration element 500 is mounted on a mounting substrate.

[0124] In the vibration element 500, the first protrusion 510 includes a third surface 8c connected to the second surface 8b, and a corner 9 formed by the second surface 8b and the third surface 8c constitutes the tip of the first protrusion 510. Therefore, in the vibration element 500, the bonding strength when mounted on a mounting board can be improved compared to a case where the tip of the first protrusion 510 does not have the corner 9.

[0125] In the vibration element 500, 30°≦θ B By satisfying 35°≦θ≦121°, the first cutout portion 310 can be made smaller in the width direction and the depth direction, and therefore the first protrusion portion 510 can be made smaller. BBy satisfying 43°≦θ≦112°, the first cutout portion 310 can be made smaller in the width direction and the depth direction, and the first protrusion portion 510 can be made smaller. B By satisfying ≦100°, the first cutout portion 310 can be made even smaller in the width direction and the depth direction, thereby making it possible to further reduce the size of the first protrusion 510. In this manner, in the vibration element 500, the first protrusion 510, which is the remaining portion of the first connection portion 300 that remains in the vibration element 500 after it is broken off, can be made small, thereby realizing a vibration element with less variation in characteristics.

[0126] The vibration element 500 includes, as the protrusions, a first protrusion 510 provided on the -Z' side of the vibration substrate 110 and a second protrusion 520 provided on the +Z' side of the vibration substrate 110. Therefore, in the vibration element 500, the bonding strength when mounted on a mounting board can be improved compared to when there is one protrusion.

[0127] 7. Sixth embodiment 7.1. Vibration element Next, the vibration element according to the sixth embodiment will be described with reference to the drawings. Fig. 25 is a cross-sectional view showing a first protrusion 510 of the vibration element 600 according to the sixth embodiment. Hereinafter, in the vibration element 600 according to the sixth embodiment, the same reference numerals are used for components having the same functions as those of the vibration element 500 according to the fifth embodiment described above, and detailed description thereof will be omitted.

[0128] 24, the first protrusion 510 has a first groove 512 formed in one main surface 2a and an inclined portion 513 formed in the other main surface 2b. In contrast, in the vibration element 500 shown in FIG 25, the first protrusion 510 has a first groove 512 formed in one main surface 2a and a second groove 514 formed in the other main surface 2b.

[0129] The second groove 514 is formed on the main surface 2b side of the vibration substrate 110. The second groove 514 corresponds to the third cutout portion 320 of the second connecting portion 400.

[0130] The second groove 514 includes a fourth surface 8d and a fifth surface 8e. The fourth surface 8d and the fifth surface 8e are inclined with respect to the main surface 2b. The fourth surface 8d and the fifth surface 8e intersect with each other. A corner 5b formed by the fourth surface 8d and the fifth surface 8e forms the bottom of the second groove 514.

[0131] The fourth surface 8d and the fifth surface 8e correspond to two inclined surfaces that form the bottom of the groove of the third cutout portion 320 shown in Fig. 7. The corner 5b formed by the fourth surface 8d and the fifth surface 8e corresponds to a corner formed by the two inclined surfaces that form the bottom of the groove of the third cutout portion 320.

[0132] The two inclined surfaces forming the bottom of the groove of the third cutout portion 320 are wet-etched surfaces formed by half-etching the quartz plate 2 in the above-mentioned step S2 of wet-etching the quartz plate 2. Therefore, the fourth surface 8d and the fifth surface 8e are wet-etched surfaces.

[0133] The third surface 8c connects the second surface 8b and the fifth surface 8e. The third surface 8c is a fracture surface formed by breaking the first connecting portion 300 in the step S6 of dividing the vibration substrate 110. Therefore, in the vibration element 600, the first surface 8a, the second surface 8b, the fourth surface 8d, and the fifth surface 8e are wet-etched surfaces, and the third surface 8c is a fracture surface.

[0134] Although not shown, in the vibration element 600, the shape of the second protrusion 520 is similar to the shape of the first protrusion 510.

[0135] 7.2. Manufacturing method The manufacturing method of the vibration element 600 is similar to the manufacturing method of the vibration element 500, except that in step S6 of singulating the above-mentioned vibration substrate 110, the breaking positions of the first connecting portion 300 and the second connecting portion 400 differ due to differences in the stresses, etc. applied to the first connecting portion 300 and the second connecting portion 400.

[0136] Effect In the vibration element 600, the first protrusion 510 is a first protrusion formed on the main surface 2b of the vibration substrate 110. The vibration element 600 has two grooves 514, and the second groove 514 includes a fourth surface 8d and a fifth surface 8e that are inclined with respect to the main surface 2b, and a corner 5b formed by the fourth surface 8d and the fifth surface 8e forms the bottom of the second groove 514. In this way, in the vibration element 600, the first protruding portion 510 has the first groove 512 and the second groove 514, and therefore, compared to, for example, a case in which the first protruding portion 510 has one groove, it is possible to enhance the anchor effect and improve the bonding strength when mounted on a mounting board.

[0137] In the fifth and sixth embodiments, the first protruding portion 510 and the second protruding portion 520 have the same shape, but at least one of the first protruding portion 510 and the second protruding portion 520 may have the configuration in Fig. 24 or 25. In addition, one of the first protruding portion 510 and the second protruding portion 520 may have the configuration in Fig. 24 and the other may have the configuration in Fig. 25.

[0138] 8. Seventh embodiment 8.1. Vibration element Next, the vibration element according to the seventh embodiment will be described with reference to the drawings. Fig. 26 is a cross-sectional view showing a first protrusion 510 of the vibration element 700 according to the seventh embodiment. Hereinafter, in the vibration element 700 according to the seventh embodiment, the same reference numerals are used for components having the same functions as those of the vibration element 500 according to the fifth embodiment and the vibration element 600 according to the sixth embodiment described above, and detailed description thereof will be omitted.

[0139] 25, the first protrusion 510 has the first groove 512 formed in one main surface 2a and the second groove 514 formed in the other main surface 2b. In contrast, in the vibration element 700 shown in Fig. 26, the first protrusion 510 has the first groove 512 formed in one main surface 2a, and no groove is formed in the other main surface 2b.

[0140] The third surface 8c is a fracture surface formed by breaking the first connecting portion 300 in the step S6 of dividing the vibration substrate 110 into individual pieces, and connects the second surface 8b and the main surface 2b.

[0141] Although not shown, in the vibration element 600, the shape of the second protrusion 520 is similar to the shape of the first protrusion 510.

[0142] 8.2. Manufacturing method The method for manufacturing the vibration element 700 is similar to the method for manufacturing the vibration element according to the third embodiment described above, and therefore the description thereof will be omitted.

[0143] Effect Like the vibration element 500 described above, the vibration element 700 can improve the bonding strength when mounted on a mounting substrate.

[0144] In this embodiment, the first protrusion 510 and the second protrusion 520 have been described as having the same shape, but it is sufficient that at least one of them has the configuration of FIG.

[0145] The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations with the same functions, methods and results, or configurations with the same purpose and effect). The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects as the configurations described in the embodiments or that can achieve the same purpose. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments.

[0146] The following can be derived from the above-described embodiment.

[0147] One aspect of the method for manufacturing a vibration element includes: forming a vibration substrate, a frame portion, and a connecting portion that connects the vibration substrate to the frame portion by wet etching a quartz plate; Breaking off the vibration substrate at the connecting portion to separate the vibration substrate from the frame portion; Including, The formation of the vibration substrate, the frame portion, and the connecting portion includes: forming a notch portion, which is a groove or a through hole, in the connecting portion along a width direction of the connecting portion; The cutout portion includes a first end portion on one side in the width direction and a second end portion on the other side in the width direction, At least one of the first end and the second end is A first side is located on the vibration substrate side and a second side is located on the frame side, The distance between the first side and the second side gradually decreases with increasing distance from the center of the cutout portion in the width direction.

[0148] In this method for manufacturing a vibration element, the distance between the first side and the second side of at least one of the first end and the second end of the connecting portion gradually decreases in the width direction of the connecting portion as it moves away from the center of the notch portion. Therefore, when the vibration substrate is broken off, stress is concentrated on the tip of at least one of the first end and the second end. Therefore, in this method for manufacturing a vibration element, it is possible to reduce the variation in the breakage position and the variation in the shape of the remaining part of the connecting portion that remains on the vibration element after breaking off.

[0149] In one embodiment of the method for manufacturing a vibration element, When the angle between the first side and the second side is θ1, the angle may satisfy 22°≦θ1≦76°.

[0150] With this method for manufacturing a vibration element, the cutout portion can be made smaller in both the width and length directions.

[0151] In one embodiment of the method for manufacturing a vibration element, When the angle between the first side and the second side is θ1, the angle may satisfy 27°≦θ1≦65°.

[0152] With this method for manufacturing a vibration element, the cutout portion can be made smaller in both the width and length directions.

[0153] In one embodiment of the method for manufacturing a vibration element, When the angle between the first side and the second side is θ1, the angle may satisfy 35°≦θ1≦52°.

[0154] With this method for manufacturing a vibration element, the cutout portion can be made even smaller in both the width and length directions.

[0155] In one embodiment of the method for manufacturing a vibration element, the cutout portion has a third side connected to the first side and a fourth side connected to the second side, When the angle between the third side and the first side is θ2, 142°≦θ2≦169° is satisfied; When the angle between the fourth side and the second side is θ3, the angle may satisfy 142°≦θ3≦169°.

[0156] In this method of manufacturing the vibration element, since 22°≦θ1≦76° is satisfied, the cutout portion can be made smaller in both the width and length directions.

[0157] In one embodiment of the method for manufacturing a vibration element, The cutout portion may be a groove.

[0158] This method of manufacturing the vibration element can reduce the possibility that the vibration element will fall off the frame during the manufacturing process.

[0159] In one embodiment of the method for manufacturing a vibration element, The cutout portion includes two inclined surfaces that intersect with each other, a corner formed by the two inclined surfaces forms a bottom of the groove; When the angle between the two inclined surfaces is θ4, the angle may satisfy 30°≦θ4≦121°.

[0160] With this method for manufacturing a vibration element, the cutout portion can be made smaller in both the depth and width directions.

[0161] In one embodiment of the method for manufacturing a vibration element, The cutout portion includes two inclined surfaces that intersect with each other, a corner formed by the two inclined surfaces forms a bottom of the groove; When the angle between the two inclined surfaces is θ4, the angle may satisfy 35°≦θ4≦112°.

[0162] With this method for manufacturing a vibration element, the cutout portion can be made smaller in both the depth and width directions.

[0163] In one embodiment of the method for manufacturing a vibration element, The cutout portion includes two inclined surfaces that intersect with each other, a corner formed by the two inclined surfaces forms a bottom of the groove; When the angle between the two inclined surfaces is θ4, the angle may satisfy 43°≦θ4≦100°.

[0164] With this method for manufacturing a vibration element, the cutout portion can be made even smaller in both depth and width directions.

[0165] In one embodiment of the method for manufacturing a vibration element, The quartz crystal plate has crystal axes defined as X-axis, Y-axis, and Z-axis, and the Y-axis and Z-axis are rotated counterclockwise around the X-axis to define the Y'-axis and Z'-axis, and has ±Y' planes including the Z'-axis and X-axis as front and back principal surfaces; The formation of the vibration substrate, the frame portion, and the connecting portion includes: The method includes forming, as the connecting portion, a first connecting portion that connects to a -Z' side of one side along the Z' direction of the vibration substrate, and a second connecting portion that connects to a +Z' side of the one side, The distance between the first side and the second side may gradually decrease from the -Z' side to the +Z' side.

[0166] This method of manufacturing a vibration element can reduce variation in the break position even when the quartz plate is an AT-cut quartz plate.

[0167] One embodiment of the quartz crystal plate is A vibration substrate; A frame portion and A connecting portion that connects the vibration substrate to the frame portion; Including, The connecting portion has a notch portion, which is a groove or a through hole, formed along a width direction of the connecting portion, The cutout portion includes a first end portion on one side in the width direction and a second end portion on the other side in the width direction, At least one of the first end and the second end is A first side is located on the vibration substrate side and a second side is located on the frame side, The distance between the first side and the second side gradually decreases with increasing distance from the center of the cutout portion in the width direction.

[0168] In this quartz crystal plate, the distance between the first side and the second side of at least one of the first and second ends of the connecting portion gradually decreases in the width direction of the connecting portion as it moves away from the center of the notch portion. Therefore, when the vibration substrate is broken off, stress is concentrated on the tip of at least one of the first and second ends. Therefore, in this quartz crystal plate, the variation in the breakage position can be reduced, and the variation in the shape of the remaining part of the connecting portion that remains on the vibration element after breaking off can be reduced.

[0169] One aspect of the vibration element is A quartz crystal substrate having the crystal axes of the quartz crystal as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and X-axis as the front and back principal surfaces; a recess provided on a side included in an outer edge of one main surface of the quartz crystal substrate; Including, The recessed portion is A first outer edge along the side; a second outer edge connected to one end of the first outer edge and inclined relative to the first outer edge; a third outer edge connected to the other end of the first outer edge and having an arcuate shape; Includes.

[0170] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0171] In one embodiment of the vibration element, The first outer edge is along the Z′ axis, The second outer edge is connected to an end of the first outer edge on the +Z' side, The third outer edge may be connected to an end on the -Z' side of the first outer edge.

[0172] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0173] In one embodiment of the vibration element, The angle between the first outer edge and the second outer edge is defined as θ A In this case, 142°≦θ A ≦169° may be satisfied.

[0174] In this vibration element, the remaining part of the connection part that remains on the vibration element after being broken off can be made small. This makes it possible to realize a vibration element with little variation in characteristics.

[0175] In one embodiment of the vibration element, The recess may include a first recess provided on the -Z' side of the quartz crystal substrate, and a second recess provided on the +Z' side of the quartz crystal substrate.

[0176] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0177] One aspect of the vibration element is A quartz crystal substrate having the crystal axes of the quartz crystal as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and X-axis as the front and back principal surfaces; a protrusion provided at an end of the quartz crystal substrate; Including, the protrusion has a first groove formed on one main surface of the quartz crystal substrate, the first groove includes a first surface and a second surface inclined with respect to the one main surface, The corner formed by the first surface and the second surface forms the bottom of the first groove.

[0178] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0179] In one aspect of the vibration element the protrusion includes a third surface connected to the second surface; A corner formed by the second surface and the third surface may constitute a tip of the protrusion.

[0180] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0181] In one aspect of the vibration element the protruding portion has a second groove formed in the other main surface, the second groove includes a fourth surface and a fifth surface inclined with respect to the other main surface, A corner formed by the fourth surface and the fifth surface may form a bottom of the second groove.

[0182] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0183] In one aspect of the vibration element The angle between the first surface and the second surface is defined as θ B When θ is 30° or less, B ≦121° may be satisfied.

[0184] With this vibration element, the protruding portion, which is the remaining portion of the connecting portion that remains on the vibration element after it is broken off, can be made small, making it possible to realize a vibration element with little variation in characteristics.

[0185] In one aspect of the vibration element The angle between the first surface and the second surface is defined as θ B When 35°≦θ B≦112° may be satisfied.

[0186] With this vibration element, the protruding portion, which is the remaining portion of the connecting portion that remains on the vibration element after it is broken off, can be made small, making it possible to realize a vibration element with little variation in characteristics.

[0187] In one aspect of the vibration element The angle between the first surface and the second surface is defined as θ B When θ is 43° or less, B ≦100° may be satisfied.

[0188] With this vibration element, the protruding portion, which is the remaining portion of the connecting portion that remains on the vibration element after it is broken off, can be made small, making it possible to realize a vibration element with little variation in characteristics.

[0189] In one aspect of the vibration element The protrusion may include a first protrusion provided on the -Z' side of the quartz crystal substrate, and a second protrusion provided on the +Z' side of the quartz crystal substrate.

[0190] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0191] In one aspect of the vibration element the first surface and the second surface are wet etched surfaces; The protrusion may include a fracture surface connecting to the second surface.

[0192] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0193] In one aspect of the vibration element the first surface and the second surface are wet etched surfaces; The third surface may be a fracture surface.

[0194] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved.

[0195] In one embodiment of the vibration element, the first surface, the second surface, the fourth surface, and the fifth surface are wet-etched surfaces; The protrusion may include a fracture surface connecting the second surface and the fourth surface.

[0196] With this vibration element, the bonding strength when it is mounted on a mounting board can be improved. [Explanation of symbols]

[0197] 2...quartz plate, 2a...main surface, 2b...main surface, 3a...first side, 3b...second side, 3c...third side, 3d...fourth side, 3e...fifth side, 4a...first inclined surface, 4b...second inclined surface, 5...corner, 5a...corner, 5b...corner, 6...first recess, 6a...first outer edge, 6b...second outer edge, 6c...third outer edge, 6d...side, 7...second recess, 8a...first surface, 8b...second surface, 8c...third surface, 8d...fourth surface, 8e...fifth surface, 9...corner, 100...vibration element, 110...vibration substrate, 111...quartz substrate, 112...side, 120...first excitation electrode, 122...first extraction electrode , 124...first electrode pad, 130...second excitation electrode, 132...second extraction electrode, 134...second electrode pad, 200...frame portion, 300...first connecting portion, 302...side wall, 304...side wall, 310...first notch portion, 312...first end portion, 314...second end portion, 316...first groove, 318...second groove, 320...third notch portion, 400...second connecting portion, 410...second notch portion, 500...vibration element, 510...first protrusion portion, 512...first groove, 513...inclined portion, 514...second groove, 520...second protrusion portion, 600...vibration element, 700...vibration element

Claims

1. forming a vibration substrate, a frame portion, and a connecting portion that connects the vibration substrate to the frame portion by wet etching a quartz plate; Breaking off the vibration substrate at the connecting portion to separate the vibration substrate from the frame portion; Including, The formation of the vibration substrate, the frame portion, and the connecting portion includes: forming a notch portion, which is a groove or a through hole, in the connecting portion along a width direction of the connecting portion; The cutout portion includes a first end portion on one side in the width direction and a second end portion on the other side in the width direction, At least one of the first end and the second end is A first side is located on the vibration substrate side and a second side is located on the frame side, A method for manufacturing a vibration element, wherein the distance between the first side and the second side gradually decreases with increasing distance from the center of the cutout portion in the width direction.

2. In claim 1, A method for manufacturing a vibration element, wherein, when an angle between the first side and the second side is θ1, 22°≦θ1≦76° is satisfied.

3. In claim 1, A method for manufacturing a vibration element, wherein, when an angle between the first side and the second side is θ1, 27°≦θ1≦65° is satisfied.

4. In claim 1, A method for manufacturing a vibration element, wherein, when an angle between the first side and the second side is θ1, 35°≦θ1≦52° is satisfied.

5. In claim 1, the cutout portion has a third side connected to the first side and a fourth side connected to the second side, When an angle between the third side and the first side is θ2, 142°≦θ2≦169° is satisfied, A method for manufacturing a vibration element, wherein, when an angle between the fourth side and the second side is θ3, 142°≦θ3≦169° is satisfied.

6. In claim 1, The method for manufacturing a vibration element, wherein the cutout portion is a groove.

7. In claim 6, The cutout portion includes two inclined surfaces that intersect with each other, a corner formed by the two inclined surfaces forms a bottom of the groove; A method for manufacturing a vibration element, wherein, when the angle between the two inclined surfaces is θ4, 30°≦θ4≦121° is satisfied.

8. In claim 6, The cutout portion includes two inclined surfaces that intersect with each other, a corner formed by the two inclined surfaces forms a bottom of the groove; When the angle between the two inclined surfaces is θ4, the following relationship is satisfied: 35°≦θ4≦112°. A method for manufacturing a vibration element.

9. In claim 6, The cutout portion includes two inclined surfaces that intersect with each other, a corner formed by the two inclined surfaces forms a bottom of the groove; A method for manufacturing a vibration element, wherein, when the angle between the two inclined surfaces is θ4, 43°≦θ4≦100° is satisfied.

10. In any one of claims 1 to 9, The quartz crystal plate has crystal axes defined as X-axis, Y-axis, and Z-axis, and the Y-axis and Z-axis are rotated counterclockwise around the X-axis to define the Y'-axis and Z'-axis, and has ±Y' planes including the Z'-axis and X-axis as front and back principal surfaces; The formation of the vibration substrate, the frame portion, and the connecting portion includes: The method includes forming, as the connecting portion, a first connecting portion connected to a −Z′ side of one side along the Z′ direction of the vibration substrate, and a second connecting portion connected to a +Z′ side of the one side, A method for manufacturing a vibration element, wherein the distance between the first side and the second side gradually decreases from the -Z' side toward the +Z' side.

11. A vibration substrate; A frame portion and A connecting portion that connects the vibration substrate to the frame portion; Including, The connecting portion has a notch portion, which is a groove or a through hole, formed along a width direction of the connecting portion, The cutout portion includes a first end portion on one side in the width direction and a second end portion on the other side in the width direction, At least one of the first end and the second end is A first side is located on the vibration substrate side and a second side is located on the frame side, A quartz crystal plate, wherein the distance between the first side and the second side gradually decreases with increasing distance from the center of the cutout portion in the width direction.

12. A quartz crystal substrate having the crystal axes of the quartz crystal as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and X-axis as the front and back principal surfaces; a recess provided on a side included in an outer edge of one main surface of the quartz crystal substrate; Including, The recessed portion is A first outer edge along the side; a second outer edge connected to one end of the first outer edge and inclined relative to the first outer edge; a third outer edge connected to the other end of the first outer edge and having an arcuate shape; A vibration element comprising:

13. In claim 12, The first outer edge is along the Z′ axis, The second outer edge is connected to an end of the first outer edge on the +Z′ side, A vibration element, wherein the third outer edge is connected to an end on the -Z' side of the first outer edge.

14. In claim 12 or 13, The angle between the first outer edge and the second outer edge is θ Ａ In this case, 142°≦θ Ａ < A vibration element that satisfies 169°.

15. In claim 12 or 13, The vibration element includes, as the recess, a first recess provided on the -Z' side of the quartz substrate and a second recess provided on the +Z' side of the quartz substrate.

16. A quartz crystal substrate having the crystal axes of the quartz crystal as the X-axis, Y-axis, and Z-axis, the Y-axis and Z-axis rotated counterclockwise around the X-axis to become the Y'-axis and Z'-axis, and having ±Y' planes including the Z'-axis and X-axis as the front and back principal surfaces; a protrusion provided at an end of the quartz crystal substrate; Including, the protrusion has a first groove formed on one main surface of the quartz crystal substrate, the first groove includes a first surface and a second surface inclined with respect to the one main surface, A vibration element, wherein a corner formed by the first surface and the second surface forms a bottom of the first groove.

17. In claim 16, the protrusion includes a third surface connected to the second surface; A vibration element, wherein a corner formed by the second surface and the third surface constitutes a tip of the protrusion.

18. In claim 16, the protrusion has a second groove formed on the other main surface of the quartz crystal substrate, the second groove includes a fourth surface and a fifth surface inclined with respect to the other main surface, A vibration element, wherein a corner formed by the fourth surface and the fifth surface forms a bottom of the second groove.

19. In any one of claims 16 to 18, The angle between the first surface and the second surface is defined as θ Ｂ When 30°≦θ Ｂ A vibration element that satisfies ≦121°.

20. In any one of claims 16 to 18, The angle between the first surface and the second surface is defined as θ Ｂ When 35°≦θ Ｂ A vibration element that satisfies ≦112°.

21. In any one of claims 16 to 18, The angle between the first surface and the second surface is defined as θ Ｂ When 43°≦θ Ｂ A vibration element that satisfies ≦100°.

22. In any one of claims 16 to 18, The vibration element includes, as the protrusion, a first protrusion provided on the -Z' side of the quartz substrate and a second protrusion provided on the +Z' side of the quartz substrate.

23. In claim 16, the first surface and the second surface are wet etched surfaces; The protrusion includes a fractured surface that connects to the second surface.

24. In claim 17, the first surface and the second surface are wet etched surfaces; The vibration element, wherein the third surface is a fracture surface.

25. In claim 18, the first surface, the second surface, the fourth surface, and the fifth surface are wet-etched surfaces; The protrusion includes a fractured surface connecting the second surface and the fourth surface.

Images