Method for manufacturing a vibrating element

Abstract

Method for manufacturing a vibrating element. The profile and the groove can be formed at the same time. The method for manufacturing a vibrating element includes: a first protective film forming step of forming a first protective film; a first dry etching step of forming a first groove and a profile of a vibrating arm by dry etching through the first protective film; a second protective film forming step of forming a second protective film in the first groove; a second dry etching step of dry etching through the second protective film; a third protective film forming step of forming a third protective film; a third dry etching step of forming a second groove and a profile of the vibrating arm by dry etching through the third protective film; a fourth protective film forming step of forming a fourth protective film in the second groove; and a fourth dry etching step of dry etching through the fourth protective film.

Description

Technical Field

[0001] This invention relates to a method for manufacturing a vibrating element. Background Technology

[0002] Patent Document 1 describes a method for forming a tuning fork-type oscillator by wet etching and dry etching, wherein the tuning fork-type oscillator has a bottomed groove on the vibrating arm. In this manufacturing method, the shape of the tuning fork-type oscillator is formed by wet etching of a quartz substrate, and then the groove is formed by dry etching.

[0003] Patent Document 2 describes a method for forming a tuning fork-type oscillator by dry etching, wherein the tuning fork-type oscillator has a bottomed groove on the vibrating arm. In this manufacturing method, when dry etching a substrate made of piezoelectric material, the width of the groove is narrowed relative to the width between a pair of vibrating arms, thereby utilizing the micro-load effect to make the etching depth of the groove shallower relative to the etching depth between a pair of vibrating arms, thus forming the groove and the outer shape of the oscillator.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2013-175933

[0005] Patent Document 2: Japanese Patent Application Publication No. 2007-013382

[0006] In the manufacturing method of Patent Document 1, the wet etching for forming the shape and the dry etching for forming the groove are different processes. Therefore, the manufacturing process is complex and prone to problems such as misalignment of the groove relative to the shape. Consequently, the vibration element based on this manufacturing method is prone to generating unwanted vibrations.

[0007] On the other hand, in the manufacturing method of Patent Document 2, the shape and groove are formed in the same process, so the above-mentioned problems do not occur. However, in this manufacturing method, the shape and groove are formed in the same process using the micro-load effect in dry etching, so the setting of dimensions such as the width of the vibrating arm and the width and depth of the groove is restricted, resulting in a low degree of design freedom.

[0008] Therefore, a manufacturing method is required that can form the shape and groove of the vibrating element simultaneously and has a high degree of design freedom. Summary of the Invention

[0009] In the manufacturing method of the vibration element of the present invention, the vibration element has a first vibration arm and a second vibration arm extending along a first direction and arranged along a second direction intersecting the first direction. The first vibration arm and the second vibration arm each have a first surface and a second surface, a first groove with a bottom opening on the first surface, and a second groove with a bottom opening on the second surface. The first surface and the second surface are arranged in a positive-negative relationship in a third direction intersecting the first direction and the second direction. A preparation step involves preparing a quartz substrate having a first substrate surface and a second substrate surface in a positive-negative relationship. A first protective film forming step involves forming a first protective film in the first substrate surface in the regions where the first vibration arm forms (the regions where the first vibration arm forms) and the second vibration arm forms (the regions where the second vibration arm forms) are located, excluding the region where the first groove forms. A first dry etching step involves dry etching the quartz substrate from the first substrate surface side through the first protective film to form the first groove and the second vibration arm. The process includes: a first protective film forming process, forming a second protective film in the first groove; a second dry etching process, dry etching the quartz substrate from the first substrate side through the second protective film to form the first surface and the outlines of the first and second vibrating arms; a third protective film forming process, forming a third protective film in the areas of the first and second vibrating arms formed on the second substrate side, excluding the area of ​​the second groove formed; a third dry etching process, dry etching the quartz substrate from the second substrate side through the third protective film to form the second groove and the outlines of the first and second vibrating arms; a fourth protective film forming process, forming a fourth protective film in the second groove; and a fourth dry etching process, dry etching the quartz substrate from the second substrate side through the fourth protective film to form the second surface and the outlines of the first and second vibrating arms. Attached Figure Description

[0010] Figure 1 This is a top view showing the vibrating element of Embodiment 1.

[0011] Figure 2 yes Figure 1 Sectional view along line A1-A1 in the diagram.

[0012] Figure 3 This is a diagram illustrating the manufacturing process of the vibration element according to Embodiment 1.

[0013] Figure 4 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0014] Figure 5It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0015] Figure 6 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0016] Figure 7 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0017] Figure 8 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0018] Figure 9 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0019] Figure 10 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0020] Figure 11 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0021] Figure 12 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0022] Figure 13 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0023] Figure 14 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0024] Figure 15 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0025] Figure 16 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0026] Figure 17 This is a cross-sectional view used to illustrate the manufacturing method of the vibration element in Embodiment 2.

[0027] Figure 18 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0028] Figure 19 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0029] Figure 20 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0030] Figure 21 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0031] Figure 22This is a top view showing a modified example of the vibrating element.

[0032] Figure 23 yes Figure 22 Sectional view along line A3-A3 in the diagram.

[0033] Figure 24 This is a top view showing a modified example of the vibrating element.

[0034] Figure 25 yes Figure 24 Sectional view along line A4-A4 in the diagram.

[0035] Figure 26 yes Figure 24 Sectional view along line A5-A5.

[0036] Figure 27 This is a top view showing a modified example of the vibrating element.

[0037] Figure 28 yes Figure 27 Sectional view along line A6-A6 in the diagram.

[0038] Figure 29 yes Figure 27 Sectional view along line A7-A7 in the diagram.

[0039] Label Explanation

[0040] 1. Vibrating element; 2. Vibrating substrate; 2A. First surface; 2B. Second surface; 3. Electrode; 20. Quartz substrate; 20A. First substrate surface; 20B. Second substrate surface; 21. Base; 22. First vibrating arm; 23. Second vibrating arm; 221, 231. First groove; 222, 232. Second groove; 225, 235. First embankment; 226, 236. Second embankment; 51, 51a. First protective film; 52. Second protective film; 61, 61a. Third protective film; 62. Fourth protective film; Q1. First groove forming area; Q2. First vibrating arm forming area; Q3. Second vibrating arm forming area; Q4. Inter-arm area Q5 Inter-component area; Q6 Second trench formation area; Qd1 First embankment formation area; Qd2 Second embankment formation area; S1 Preparation process; S2 First protective film formation process; S3 First dry etching process; S4 Second protective film formation process; S5 Second dry etching process; S6 First protective film removal process; S7 Second protective film removal process; S8 Third protective film formation process; S9 Third dry etching process; S10 Fourth protective film formation process; S11 Fourth dry etching process; S12 Third protective film removal process; S13 Fourth protective film removal process; S14 Electrode formation process. Detailed Implementation

[0041] 1. Implementation Method 1

[0042] The manufacturing method of the vibration element 1 in Embodiment 1 will be described.

[0043] First, refer to Figure 1 and Figure 2 The structure of vibrating element 1 will be explained, and then, referring to... Figures 3 to 10 The manufacturing method of vibration element 1 is explained.

[0044] For ease of explanation, except Figure 3 In the figures other than those shown, the X-axis, Y-axis, and Z-axis are shown as three mutually orthogonal axes. Furthermore, the direction along the X-axis, which is considered the second direction, is also called the X-direction; the direction along the Y-axis, which is considered the first direction, is also called the Y-direction; and the direction along the Z-axis, which is considered the third direction, is also called the Z-direction. Additionally, the arrow side of each axis is also called the positive side, and the opposite side is also called the negative side. Furthermore, the positive side of the Z-direction is also called "up," and the negative side is also called "down." Additionally, the view from the Z-direction is simply referred to as "top view." Furthermore, as described later, the X-axis, Y-axis, and Z-axis correspond to the crystal axes of quartz.

[0045] like Figure 1 and Figure 2 As shown, the vibrating element 1 is a tuning fork type vibrating element, having a vibrating substrate 2 and electrodes 3 formed on the surface of the vibrating substrate 2.

[0046] The vibrating substrate 2 is formed by patterning a Z-cut quartz substrate, which is a Z-cut quartz plate, into a desired shape. It extends along the XY plane, defined by the X-axis and Y-axis, which are the axes of the quartz crystal, and has a thickness along the Z-direction. The X-axis is also called the electrical axis, the Y-axis is also called the mechanical axis, and the Z-axis is also called the optical axis. In addition, the thickness along the Z-direction is also simply referred to as "thickness".

[0047] The vibrating substrate 2 is plate-shaped and has a first surface 2A and a second surface 2B arranged opposite each other along the Z direction. Furthermore, the vibrating substrate 2 has a base 21 and a first vibrating arm 22 and a second vibrating arm 23 extending from the base 21 along the Y direction and arranged along the X direction.

[0048] The first vibrating arm 22 has a first groove 221 with a bottom that opens on a first surface 2A, a first embankment 225 that defines the first groove 221, a second groove 222 with a bottom that opens on a second surface 2B, a second embankment 226 that defines the second groove 222, and a side surface 101 connecting the first surface 2A and the second surface 2B. The first embankment 225 is the portion on the first surface 2A arranged along the X direction and separated by the first groove 221 when viewed from above. The second embankment 226 is the portion on the second surface 2B arranged along the X direction and separated by the second groove 222 when viewed from above.

[0049] Similarly, the second vibrating arm 23 has a bottomed first groove 231 opening on the first surface 2A, a first embankment 235 defining the first groove 231, a bottomed second groove 232 opening on the second surface 2B, a second embankment 236 defining the second groove 232, and a side surface 103 connecting the first surface 2A and the second surface 2B. The first embankment 235 is the portion on the first surface 2A arranged along the X direction, separated by the first groove 231, when viewed from above. The second embankment 236 is the portion on the second surface 2B arranged along the X direction, separated by the second groove 232, when viewed from above.

[0050] The first grooves 221 and 231 and the second grooves 222 and 232 extend along the Y direction. Furthermore, the first embankments 225 and 235 are formed on both sides of the first grooves 221 and 231 in the X direction and extend along the Y direction. The second embankments 226 and 236 are formed on both sides of the second grooves 222 and 232 in the X direction and extend along the Y direction. Therefore, the first vibrating arm 22 and the second vibrating arm 23 each have a generally H-shaped cross-sectional shape. This results in a vibrating element 1 that reduces thermoelastic losses and possesses excellent vibration characteristics.

[0051] Electrode 3 has a signal electrode 31 and a ground electrode 32. The signal electrode 31 is disposed on the first surface 2A and the second surface 2B of the first vibrating arm 22 and on the side surface 103 of the second vibrating arm 23. Conversely, the ground electrode 32 is disposed on the side surface 101 of the first vibrating arm 22 and on the first surface 2A and the second surface 2B of the second vibrating arm 23. When a drive signal is applied to the signal electrode 31 with the ground electrode 32 grounded, as... Figure 1 As indicated by the arrows, the first vibrating arm 22 and the second vibrating arm 23 undergo bending vibration in the X direction by repeatedly approaching and separating.

[0052] The above provides a brief description of the vibrating element 1.

[0053] Next, the manufacturing method of the vibrating element 1 will be described. For example... Figure 3As shown, the manufacturing method of the vibrating element 1 includes: a preparation step S1, preparing a quartz substrate 20 as the parent material for the vibrating substrate 2; a first protective film formation step S2, forming a first protective film 51 on a first substrate surface 20A of the quartz substrate 20; a first dry etching step S3, dry etching the quartz substrate 20 through the first protective film 51 to form first grooves 221 and 231; a second protective film formation step S4, forming a second protective film 52 in the first grooves 221 and 231; a second dry etching step S5, dry etching the quartz substrate 20 through the second protective film 52; a first protective film removal step S6, removing the first protective film 51 remaining on the first substrate surface 20A; and a second protective film removal step S7, removing the second protective film 52 remaining in the first grooves 221 and 231. The process includes: a third protective film forming process S8, forming a third protective film 61 on the second substrate surface 20B of the quartz substrate 20; a third dry etching process S9, dry etching the quartz substrate 20 through the third protective film 61 to form the second trenches 222 and 232; a fourth protective film forming process S10, forming a fourth protective film 62 in the second trenches 222 and 232; a fourth dry etching process S11, dry etching the quartz substrate 20 through the fourth protective film 62; a third protective film removal process S12, removing the third protective film 61 remaining on the second substrate surface 20B; a fourth protective film removal process S13, removing the fourth protective film 62 remaining on the second trenches 222 and 232; and an electrode forming process S14, forming an electrode 3 on the surface of the vibrating substrate 2 obtained through the above processes.

[0054] Furthermore, the first protective film removal step S6 corresponds to the "first removal step" in this invention. The third protective film removal step S12 corresponds to the "second removal step" in this invention.

[0055] The following sections will explain each of these processes in turn.

[0056] <<Preparation Process S1>>

[0057] like Figure 4 As shown, a quartz substrate 20 is prepared as the base material for the vibrating substrate 2. Multiple vibrating elements 1 are formed together from the quartz substrate 20. The quartz substrate 20 is plate-shaped and has a first substrate surface 20A and a second substrate surface 20B arranged opposite each other in the Z direction. Through grinding or polishing processes, the quartz substrate 20 is adjusted to a desired thickness, and the first substrate surface 20A and the second substrate surface 20B are sufficiently smoothed. Alternatively, if necessary, a surface treatment based on wet etching can be performed on the quartz substrate 20.

[0058] Furthermore, the region where the first vibrating arm 22 is formed will be referred to as the first vibrating arm forming region Q2. The region where the second vibrating arm 23 is formed will also be referred to as the second vibrating arm forming region Q3. In addition, the region located between the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 will also be referred to as the inter-arm region Q4. Furthermore, the region located between adjacent vibrating substrates 2 will also be referred to as the inter-element region Q5.

[0059] The first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 have a first groove forming region Q1 that forms the first grooves 221 and 231 and a first embankment forming region Qd1 that forms the first embankment portions 225 and 235. In other words, the first embankment forming region Qd1 corresponds to the region in the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 other than the first groove forming region Q1. The first grooves 221 and 231 and the first embankment portions 225 and 235 are formed by the first dry etching process S3 described later.

[0060] Furthermore, the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 have a second groove forming region Q6 that forms the second grooves 222 and 232, and a second embankment forming region Qd2 that forms the second embankments 226 and 236. In other words, the second embankment forming region Qd2 corresponds to the region in the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 other than the second groove forming region Q6. The second grooves 222 and 232 and the second embankments 226 and 236 are formed by the third dry etching process S9 described later.

[0061] <<First Protective Film Forming Process S2>>

[0062] like Figure 5 As shown, a first protective film 51 is formed on the first substrate surface 20A of the quartz substrate 20. The first protective film 51 is formed in the first embankment forming region Qd1 on the first substrate surface 20A.

[0063] In this embodiment, the first protective film 51 is a resin film formed from resin. For example, the first protective film 51 can be formed by coating a photoresist material, which is a photosensitive resin, onto the first substrate surface 20A and patterning it using photolithography. Alternatively, the first protective film 51 can also be formed by selectively coating resin using a printing method such as screen printing or embossing. In this way, a resin film can be easily formed, and by making the first protective film 51 a resin film, the first protective film formation process S2 can be simplified.

[0064] In this embodiment, the first protective film 51 is formed to be thick enough that it remains in the first embankment formation region Qd1 at the end of the first dry etching process S3 and the second dry etching process S5, which will be described later. However, the first protective film 51 may also be formed to be thinner so that it can be removed from the first embankment formation region Qd1 at the end of the first dry etching process S3 or the second dry etching process S5.

[0065] In this embodiment, the first protective film 51 is formed of resin, but it may also be formed of a material other than resin. For example, the first protective film 51 may also be a metal film formed of metal.

[0066] <<First Dry Etching Process S3>>

[0067] like Figure 6 As shown, the quartz substrate 20 is dry etched from the first substrate surface 20A side through the first protective film 51, simultaneously forming the first grooves 221 and 231 and the outline of the vibrating substrate 2. Furthermore, "simultaneous formation" means forming both in a single process. More specifically, this process is reactive ion etching, performed using a reactive ion etching apparatus (RIE apparatus). Additionally, the reactive gas introduced into the RIE apparatus is not particularly limited; for example, SF6, CF4, C2F4, C2F6, C3F6, C4F8, etc., can be used.

[0068] In this process, the first protective film 51 formed in the first dam formation region Qd1 is used as a mask to etch the area outside the dam formation region Qd1. The area outside the first dam formation region Qd1 is the first trench formation region Q1, the inter-arm region Q4, and the inter-element region Q5. The first trenches 221 and 231 are formed by etching the first trench formation region Q1 of the quartz substrate 20 from the first substrate surface 20A side. The etching depth in the first trench formation region Q1 is equivalent to the depth of the first trenches 221 and 231. The shape of the vibrating substrate 2 is formed by etching the inter-arm region Q4 and the inter-element region Q5 of the quartz substrate 20 from the first substrate surface 20A side. The etching depth in the inter-arm region Q4 and the inter-element region Q5 is equivalent to the depth of the shape of the vibrating substrate 2. In addition, the "shape of the vibrating substrate 2" is also referred to as the "shape of the first vibrating arm 22 and the second vibrating arm 23".

[0069] The first dry etching process S3 ends when the depth of the first grooves 221 and 231 reaches the desired depth Wa. In this embodiment, the depth of the shape of the vibrating substrate 2 at the end of this process is approximately equal to the depth Wa of the first grooves 221 and 231. Furthermore, "approximately equal" is a concept that includes cases where they are not strictly equal due to deviations in etching conditions, etc.

[0070] Furthermore, in this embodiment, as described above, the first protective film 51 is formed in the first embankment forming region Qd1 on the first substrate surface 20A, but not in the first trench forming region Q1, the inter-arm region Q4, and the inter-component region Q5. That is, the first trench forming region Q1, the inter-arm region Q4, and the inter-component region Q5 on the first substrate surface 20A are exposed. Therefore, in the first dry etching process S3, etching of the first trench forming region Q1, the inter-arm region Q4, and the inter-component region Q5 begins simultaneously with the start of dry etching. Therefore, the first dry etching process S3 can be performed in a short time.

[0071] <<Second Protective Film Forming Process S4>>

[0072] like Figure 7 As shown, a second protective film 52 is formed in the first grooves 221 and 231.

[0073] In this embodiment, the second protective film 52 is a resin film formed from resin. The second protective film 52 is formed by filling the first grooves 221 and 231 with resin. For example, the second protective film 52 can be formed by coating a photoresist material as a photosensitive resin onto the quartz substrate 20 from the first substrate surface 20A side and patterning it using photolithography. Alternatively, for example, the second protective film 52 can also be formed by selectively coating resin using a printing method such as screen printing or embossing. In this way, a resin film can be easily formed, so by making the second protective film 52 a resin film, the second protective film formation process S4 can be simplified.

[0074] In this embodiment, the thickness of the second protective film 52 is formed to be greater than or equal to the depth Wa of the first trenches 221 and 231 at the end of the second dry etching process S5 described later. However, the thickness of the second protective film 52 is formed to be thick enough that the second protective film 52 remains on the bottom surface of the first trenches 221 and 231 at the end of the second dry etching process S5.

[0075] In addition, in this embodiment, the second protective film 52 is a thick film formed by filling the first grooves 221 and 231 with resin, but it can also be a thin film covering the sidewalls and bottom surface of the first grooves 221 and 231 respectively.

[0076] In this embodiment, the second protective film 52 is formed of resin, but it can also be formed of materials other than resin. For example, the second protective film 52 can also be a metal film formed of metal.

[0077] <<Second Dry Etching Process S5>>

[0078] like Figure 8As shown, the quartz substrate 20 is dry-etched from the first substrate surface 20A side through the second protective film 52, simultaneously forming the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23, as well as the outline of the vibrating substrate 2. This process is reactive ion etching and is performed using a RIE device.

[0079] In this process, the second protective film 52 formed in the first trench formation region Q1 is used as a mask to etch the area outside the first trench formation region Q1. However, in this embodiment, as described above, the first protective film 51 remains in the first embankment formation region Qd1. Therefore, in this process, the first protective film 51 and the second protective film 52 are used as masks to etch the area of ​​the quartz substrate 20 other than the first trench formation region Q1 and the first embankment formation region Qd1. The area outside the first trench formation region Q1 and the first embankment formation region Qd1 is the inter-arm region Q4 and the inter-element region Q5.

[0080] Thus, the shape of the vibrating substrate 2 is formed by etching the inter-arm region Q4 and inter-element region Q5 of the quartz substrate 20 from the first substrate surface 20A side.

[0081] The second dry etching process S5 ends when the depth of the outer shape of the vibrating substrate 2 reaches the desired depths Aa and Ba. That is, at the end of this process, the etching depth of the inter-arm region Q4 is depth Aa, and the etching depth of the inter-component region Q5 is depth Ba. In this embodiment, depths Aa and Ba are approximately equal.

[0082] In this embodiment, at the end of this process, the depths Aa and Ba of the outer shape of the vibrating substrate 2 are more than half the thickness Ta of the quartz substrate 20.

[0083] Furthermore, in this embodiment, the depths Aa and Ba of the outer shape of the vibrating substrate 2 are shallower than the difference Ta-Wb between the thickness Ta of the quartz substrate 20 and the depth Wb of the second trenches 222 and 232 formed in the third dry etching process S9 described later. <Ta-Wb,Ba<Ta-Wb。

[0084] Furthermore, in this embodiment, the dry etching process S5 ends with the first protective film 51 remaining on the first substrate surface 20A of the quartz substrate 20. That is, the first embankment formation region Qd1 on the first substrate surface 20A is protected by the first protective film 51 and is not etched in the first dry etching process S3 and the second dry etching process S5. In the first protective film removal process S6, described later, the first embankment formation region Qd1 on the first substrate surface 20A becomes the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23.

[0085] In the second dry etching process S5, the dry etching can also be completed before the first protective film 51 remains on the first substrate surface 20A. That is, the first embankment formation region Qd1 can also be etched. In this case, the surface etched in the second dry etching process S5 becomes the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23.

[0086] Thus, the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23 is formed by etching or not etching the first embankment forming region Qd1 of the first substrate surface 20A.

[0087] Here, the first protective film formation process S2, the first dry etching process S3, the second protective film formation process S4, and the second dry etching process S5 are summarized as follows.

[0088] According to dry etching, the process can be carried out without being affected by the quartz crystal plane, so the shapes of the first grooves 221, 231, the first vibrating arm 22, and the second vibrating arm 23 can be formed with excellent dimensional accuracy.

[0089] Furthermore, by forming the first grooves 221 and 231 and the outer shape of the vibrating substrate 2 together, the manufacturing process of the vibrating element 1 can be reduced, thereby lowering the cost of the vibrating element 1. In addition, since the positional displacement of the first grooves 221 and 231 relative to the outer shape is prevented, the forming accuracy of the vibrating substrate 2 can be improved.

[0090] Furthermore, the shapes of the first grooves 221 and 231, as well as the first vibrating arm 22 and the second vibrating arm 23, can be formed without utilizing the micro-load effect. Therefore, there are no restrictions on setting the dimensions such as the width of the inter-arm region Q4, the width of the inter-element region Q5, and the width of the first grooves 221 and 231, which can improve the design freedom of the vibrating element 1. For example, in the first protective film forming process S2, the external dimensions of the first grooves 221 and 231, as well as the first vibrating arm 22 and the second vibrating arm 23, can be controlled by adjusting the thickness or width of the first protective film 51.

[0091] Furthermore, since the micro-load effect is not utilized, the constraints of dry etching conditions, such as the selection of reactive gases used in dry etching, are mitigated. Therefore, compared with the case of utilizing the micro-load effect, it is easier to manufacture the vibrating element 1.

[0092] <<First Protective Film Removal Process S6>>

[0093] like Figure 9As shown, the first protective film 51 remaining on the first substrate surface 20A of the quartz substrate 20 is removed. Thus, the first substrate surface 20A becomes the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23. The first surface 2A of the first vibrating arm 22 and the second vibrating arm 23 is not etched in the first dry etching process S3 and the second dry etching process S5. Therefore, the thickness of the first vibrating arm 22 and the second vibrating arm 23 and the surface roughness of the first surface 2A maintain the thickness of the quartz substrate 20 and the surface roughness of the first substrate surface 20A. Therefore, the thickness accuracy of the first vibrating arm 22 and the second vibrating arm 23 is improved, suppressing the generation of unwanted vibrations such as torsional vibration.

[0094] Alternatively, if the first protective film 51 is removed from the first substrate surface 20A without any residue at the end of the second dry etching process S5, the first protective film removal process S6 may not be performed.

[0095] <<Second Protective Film Removal Process S7>>

[0096] like Figure 10 As shown, the second protective film 52 remaining in the first groove 221 and 231 is removed.

[0097] Furthermore, the order in which the first protective film removal step S6 and the second protective film removal step S7 are performed is not limited to this order, and the execution order can be changed. Alternatively, the first protective film removal step S6 and the second protective film removal step S7 can be performed as a single step, removing the first protective film 51 and the second protective film 52 together.

[0098] After the second protective film removal process S7 is completed, the process is transferred to the second substrate surface 20B of the quartz substrate 20.

[0099] <<Third protective film formation process S8>>

[0100] This process is performed in the same manner as the first protective film formation process S2.

[0101] like Figure 11 As shown, a third protective film 61 is formed on the second substrate surface 20B of the quartz substrate 20. The third protective film 61 is formed in the second embankment region Qd2 on the second substrate surface 20B.

[0102] In this embodiment, the third protective film 61 is a resin film formed from resin. By making the third protective film 61 a resin film, the third protective film forming process S8 can be simplified.

[0103] In this embodiment, the third protective film 61 is formed to be thick enough that it remains in the second embankment formation region Qd2 at the end of the third dry etching process S9 and the fourth dry etching process S11, which will be described later. However, the third protective film 61 may also be formed to be thinner so that it can be removed from the second embankment formation region Qd2 at the end of the third dry etching process S9 or the fourth dry etching process S11.

[0104] In this embodiment, the third protective film 61 is formed of resin, but it may also be formed of a material other than resin. For example, the third protective film 61 may also be a metal film formed of metal.

[0105] <<Third Dry Etching Process S9>>

[0106] This process is performed in the same way as the first dry etching process S3.

[0107] like Figure 12 As shown, the quartz substrate 20 is dry-etched from the second substrate surface 20B side through the third protective film 61, while forming the second grooves 222 and 232 and the shape of the vibrating substrate 2.

[0108] In this process, using the third protective film 61 formed in the second embankment formation region Qd2 as a mask, the quartz substrate 20 is etched in the second trench formation region Q6, the inter-arm region Q4, and the inter-element region Q5. The second trenches 222 and 232 are formed by etching the second trench formation region Q6 of the quartz substrate 20 from the second substrate surface 20B side. The etching depth in the second trench formation region Q6 corresponds to the depth of the second trenches 222 and 232. The shape of the vibrating substrate 2 is formed by etching the inter-arm region Q4 and the inter-element region Q5 of the quartz substrate 20 from the second substrate surface 20B side.

[0109] The third dry etching process S9 ends when the depth of the second trenches 222 and 232 reaches the desired depth Wb. In this embodiment, the depth of the outer shape of the vibrating substrate 2 at the end of this process is approximately equal to the depth Wb of the second trenches 222 and 232.

[0110] Furthermore, in this embodiment, as described above, the third protective film 61 is formed in the second embankment forming region Qd2 on the second substrate surface 20B, but not in the second trench forming region Q6, the inter-arm region Q4, and the inter-component region Q5. That is, the second trench forming region Q6, the inter-arm region Q4, and the inter-component region Q5 on the second substrate surface 20B are exposed. Therefore, in the third dry etching process S9, etching of the second trench forming region Q6, the inter-arm region Q4, and the inter-component region Q5 begins simultaneously with the start of dry etching. Therefore, the third dry etching process S9 can be performed in a short time.

[0111] <<4th Protective Film Forming Process S10>>

[0112] This process is performed in the same manner as the second protective film formation process S4.

[0113] like Figure 13 As shown, a fourth protective film 62 is formed in the second grooves 222 and 232.

[0114] In this embodiment, the fourth protective film 62 is a resin film formed from resin. The fourth protective film 62 is formed by embedding resin into the second grooves 222 and 232. By making the fourth protective film 62 a resin film, the fourth protective film formation process S10 can be simplified.

[0115] In this embodiment, the thickness of the fourth protective film 62 is formed to be greater than or equal to the depth Wb of the second trenches 222 and 232 at the end of the fourth dry etching process S11 described later. However, the thickness of the fourth protective film 62 is formed to be sufficient so that the fourth protective film 62 remains on the bottom surface of the second trenches 222 and 232 at the end of the fourth dry etching process S11.

[0116] In addition, in this embodiment, the fourth protective film 62 is a thick film formed by embedding resin into the second grooves 222 and 232, but it can also be a thin film covering the sidewalls and bottom surfaces of the second grooves 222 and 232 respectively.

[0117] In this embodiment, the fourth protective film 62 is formed of resin, but it may also be formed of a material other than resin. For example, the fourth protective film 62 may also be a metal film formed of metal.

[0118] <<Fourth Dry Etching Process S11>>

[0119] This process is performed in the same way as the second dry etching process S5.

[0120] like Figure 14 As shown, the quartz substrate 20 is dry-etched from the second substrate surface 20B side through the fourth protective film 62, thereby forming the second surface 2B of the first vibration arm 22 and the second vibration arm 23, as well as the outline of the vibration substrate 2.

[0121] In this process, the fourth protective film 62 formed in the second trench formation region Q6 is used as a mask to etch the area outside the second trench formation region Q6. However, in this embodiment, as described above, the third protective film 61 remains in the second embankment formation region Qd2. Therefore, in this process, the third protective film 61 and the fourth protective film 62 are used as masks to etch the inter-arm region Q4 and the inter-element region Q5 of the quartz substrate 20.

[0122] Thus, the shape of the vibrating substrate 2 is formed by etching the inter-arm region Q4 and inter-element region Q5 of the quartz substrate 20 from the second substrate surface 20B side.

[0123] The fourth dry etching process S11 ends when the depth of the outer shape of the vibrating substrate 2 reaches the desired depths Ab and Bb. That is, at the end of this process, the etching depth of the inter-arm region Q4 is depth Ab, and the etching depth of the inter-component region Q5 is depth Bb. In this embodiment, depth Ab and depth Bb are approximately equal.

[0124] In this embodiment, at the end of this process, the depths Ab and Bb of the outer shape of the vibrating substrate 2 are more than half the thickness Ta of the quartz substrate 20. By making the depths Aa and Ba and the depths Ab and Bb more than half the thickness Ta of the quartz substrate 20, the inter-arm region Q4 and the inter-element region Q5 are respectively connected in the fourth dry etching process S11. By connecting the inter-arm region Q4 and the inter-element region Q5, the first vibrating arm 22 and the second vibrating arm 23 are formed.

[0125] Furthermore, in this embodiment, the dry etching process S11 ends with the third protective film 61 remaining on the second substrate surface 20B of the quartz substrate 20. That is, the second embankment formation region Qd2 on the second substrate surface 20B is protected by the third protective film 61 and is not etched in the third dry etching process S9 and the fourth dry etching process S11. In the third protective film removal process S12, described later, the second embankment formation region Qd2 on the second substrate surface 20B becomes the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23.

[0126] Alternatively, in the fourth dry etching process S11, the dry etching can be completed when the third protective film 61 does not remain on the second substrate surface 20B. In this case, the surface etched in the fourth dry etching process S11 becomes the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23.

[0127] Thus, the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23 is formed by etching or not etching the second embankment forming region Qd2 of the second substrate surface 20B.

[0128] Here, the third protective film formation process S8, the third dry etching process S9, the fourth protective film formation process S10, and the fourth dry etching process S11 are summarized as follows.

[0129] According to dry etching, the process can be carried out without being affected by the quartz crystal plane, so the shape of the second groove 222, 232 and the first vibrating arm 22 and the second vibrating arm 23 can be formed with excellent dimensional accuracy.

[0130] Furthermore, by forming the second grooves 222 and 232 and the outer shape of the vibration substrate 2 together, it is possible to reduce the manufacturing process of the vibration element 1 and lower the cost of the vibration element 1. In addition, by preventing the second grooves 222 and 232 from shifting position relative to the outer shape, the forming accuracy of the vibration substrate 2 can be improved.

[0131] Furthermore, since the shapes of the second grooves 222 and 232, as well as the first and second vibrating arms 22 and 23, can be formed without utilizing micro-load effects, there are no restrictions on setting dimensions such as the width of the inter-arm region Q4, the width of the inter-element region Q5, and the width of the second grooves 222 and 232, thus increasing the design freedom of the vibrating element 1. For example, in the third protective film forming process S8, the external dimensions of the second grooves 222 and 232, as well as the first and second vibrating arms 22 and 23, can be controlled by adjusting the thickness or width of the third protective film 61.

[0132] Furthermore, since the micro-load effect is not utilized, the constraints of dry etching conditions, such as the selection of reactive gases used in dry etching, are mitigated. Therefore, compared with the case of utilizing the micro-load effect, it is easier to manufacture the vibrating element 1.

[0133] <<Third Protective Film Removal Process S12>>

[0134] This process is performed in the same manner as the first protective film removal process S6.

[0135] like Figure 15 As shown, the third protective film 61 remaining on the second substrate surface 20B of the quartz substrate 20 is removed. Thus, the second substrate surface 20B becomes the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23. The second surface 2B of the first vibrating arm 22 and the second vibrating arm 23 is not etched in the third dry etching process S9 and the fourth dry etching process S11. Therefore, the thickness of the first vibrating arm 22 and the second vibrating arm 23 and the surface roughness of the second surface 2B maintain the thickness of the quartz substrate 20 and the surface roughness of the second substrate surface 20B. Therefore, the thickness accuracy of the first vibrating arm 22 and the second vibrating arm 23 is improved, suppressing the generation of unwanted vibrations such as torsional vibration.

[0136] Alternatively, if the third protective film 61 is removed from the second substrate surface 20B without any residue after the fourth dry etching process S11 is completed, the third protective film removal process S12 may not be performed.

[0137] <<Step 4: Protective Film Removal S13>>

[0138] This process is performed in the same way as the second protective film removal process S7.

[0139] like Figure 16As shown, the fourth protective film 62 remaining in the second grooves 222 and 232 is removed.

[0140] Furthermore, the order in which the third protective film removal step S12 and the fourth protective film removal step S13 are performed is not limited to this order, and the execution order can be changed. Alternatively, the third protective film removal step S12 and the fourth protective film removal step S13 can be performed as a single step, removing the third protective film 61 and the fourth protective film 62 together.

[0141] Alternatively, the first protective film removal step S6 can be omitted, and the first protective film 51 and the third protective film 61 can be removed together in the third protective film removal step S12. Alternatively, the second protective film removal step S7 can be omitted, and the second protective film 52 and the fourth protective film 62 can be removed together in the fourth protective film removal step S13. Alternatively, the first protective film removal step S6, the second protective film removal step S7, and the third protective film removal step S12 can be omitted, and the first protective film 51, the second protective film 52, the third protective film 61, and the fourth protective film 62 can be removed together in the fourth protective film removal step S13.

[0142] Through the above processes S1 to S13, as follows Figure 16 As shown, multiple vibrating substrates 2 are formed together from the quartz substrate 20.

[0143] <<Electrode Formation Process S14>>

[0144] A metal film is formed on the surface of the vibrating substrate 2, and an electrode 3 is formed by patterning the metal film.

[0145] Thus, vibration element 1 is obtained.

[0146] As described above, the following effects can be obtained according to this embodiment.

[0147] In the manufacturing method of the vibrating element 1, the vibrating element 1 has a first vibrating arm 22 and a second vibrating arm 23 extending along the Y direction (a first direction) and arranged along the X direction (a second direction) intersecting the Y direction. The first vibrating arm 22 and the second vibrating arm 23 each have a first surface 2A and a second surface 2B, a first groove 221 and 231 with a bottom opening on the first surface 2A, and a second groove 222 and 232 with a bottom opening on the second surface 2B. The first surface 2A and the second surface 2B are arranged in a positive-negative relationship along the Z direction (a third direction) intersecting the Y and X directions. The manufacturing method includes: quasi- Preparation step S1: Prepare a quartz substrate 20 having a first substrate surface 20A and a second substrate surface 20B in a front-back relationship; First protective film formation step S2: Form a first protective film 51 in the first vibrating arm forming region Q2 (forming the first vibrating arm 22) and the second vibrating arm forming region Q3 (forming the second vibrating arm 23) on the first substrate surface 20A, excluding the first trench forming region Q1 (forming the first trenches 221 and 231), i.e., the first embankment forming region Qd1; First dry etching step S3: Dry etch the quartz substrate 20 from the first substrate surface 20A side through the first protective film 51 to form the first trench. The outer shapes of 221, 231, and the first vibrating arm 22 and the second vibrating arm 23 are formed; in the second protective film formation process S4, a second protective film 52 is formed in the first grooves 221 and 231; in the second dry etching process S5, the quartz substrate 20 is dry etched from the first substrate surface 20A side through the second protective film 52 to form the first surface 2A and the outer shapes of the first vibrating arm 22 and the second vibrating arm 23; in the third protective film formation process S8, the outer shapes of the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 on the second substrate surface 20B, excluding the second groove forming region Q6 that forms the second grooves 222 and 232, are formed. The third protective film 61 is formed in the area Qd2 of the second embankment; in the third dry etching process S9, the quartz substrate 20 is dry etched from the side of the second substrate surface 20B through the third protective film 61 to form the shape of the second grooves 222 and 232 and the shape of the first vibrating arm 22 and the second vibrating arm 23; in the fourth protective film forming process S10, the fourth protective film 62 is formed in the second grooves 222 and 232; and in the fourth dry etching process S11, the quartz substrate 20 is dry etched from the side of the second substrate surface 20B through the fourth protective film 62 to form the shape of the second surface 2B and the shape of the first vibrating arm 22 and the second vibrating arm 23.

[0148] Therefore, the shapes of the first vibrating arm 22 and the second vibrating arm 23, the first grooves 221 and 231, and the second grooves 222 and 232 can be formed simultaneously. Furthermore, there are no restrictions on the setting of dimensions such as the width of the inter-arm region Q4, the width of the inter-element region Q5, the width of the first grooves 221 and 231, and the width of the second grooves 222 and 232, which provides a manufacturing method for a vibrating element 1 with a high degree of design freedom.

[0149] Furthermore, as described above, by making the first protective film 51 and the third protective film 61 formed in the first embankment forming region Qd1 and the second embankment forming region Qd2, respectively, and the second protective film 52 and the fourth protective film 62 formed in the first trench forming region Q1 and the second trench forming region Q6, respectively, into resin films, the first protective film forming process S2, the second protective film forming process S4, the third protective film forming process S8, and the fourth protective film forming process S10 can be simplified.

[0150] 2. Implementation Method 2

[0151] Reference Figures 17-21 The manufacturing method of the vibration element 1 in Embodiment 2 is described below. Furthermore, structures identical to those in Embodiment 1 are labeled with the same reference numerals, and repeated descriptions are omitted.

[0152] In Embodiment 2, the first protective film 51a formed in the first embankment forming region Qd1 in the first protective film forming step S2 is a metal film, and the first protective film 51a has a first metal film 511 and a second metal film 512. The third protective film 61a formed in the second embankment forming region Qd2 in the third protective film forming step S8 is a metal film, and the third protective film 61a has a third metal film 611 and a fourth metal film 612. In the first protective film forming step S2, the first metal film 511 is formed in the region other than the first embankment forming region Qd1. In the third protective film forming step S8, the third metal film 611 is formed in the region other than the second embankment forming region Qd2. Otherwise, it is the same as Embodiment 1.

[0153] Furthermore, the first metal film 511 formed in the first groove forming region Q1 in the region other than the first dike forming region Qd1 corresponds to the fifth protective film 55 in this invention. The third metal film 611 formed in the second groove forming region Q6 in the region other than the second dike forming region Qd2 corresponds to the sixth protective film 65 in this invention. The first metal film 511 formed in the inter-arm region Q4 and inter-element region Q5 in the region other than the first dike forming region Qd1 corresponds to the seventh protective film 57 in this invention. The third metal film 611 formed in the inter-arm region Q4 and inter-element region Q5 in the region other than the second dike forming region Qd2 corresponds to the eighth protective film 67 in this invention.

[0154] The preparation process S1 is the same as in Embodiment 1, so the description is omitted and the description will proceed from the first protective film formation process S2.

[0155] <<First Protective Film Forming Process S2>>

[0156] like Figure 17As shown, firstly, a first metal film 511 is formed on the first substrate surface 20A of the quartz substrate 20. The first metal film 511 is a base film used to promote the formation of the second metal film 512, which will be described later. The first metal film 511 can be formed, for example, from copper (Cu), chromium (Cr), etc. The first metal film 511 can be formed, for example, using a vapor phase deposition method such as sputtering or evaporation.

[0157] Next, a first resist film R1 is formed on the side of the first metal film 511 opposite to the quartz substrate 20 using photolithography. The side of the first metal film 511 opposite to the quartz substrate 20 is the positive side of the first metal film 511 in the Z direction. The first resist film R1 has an opening in the first embankment forming region Qd1. In other words, the first resist film R1 is patterned in a manner that allows the second metal film 512 to be formed in the first embankment forming region Qd1.

[0158] Next, a second metal film 512 is formed on the surface of the first metal film 511 opposite to the quartz substrate 20 through the opening of the first resist film R1. That is, the first resist film R1 is used as a mask to laminate the second metal film 512 on the first metal film 511. In this way, a first protective film 51a having the first metal film 511 and the second metal film 512 is formed in the first embankment forming region Qd1 on the first substrate surface 20A. The second metal film 512 can be formed, for example, by nickel (Ni). The second metal film 512 can be formed, for example, by an electroless plating method.

[0159] After the first protective film 51a is formed, the first resist film R1 is removed. Thus, it becomes... Figure 18 That way.

[0160] like Figure 18 As shown, a first protective film 51a having a first metal film 511 and a second metal film 512 is formed in the first embankment forming region Qd1 on the first substrate surface 20A.

[0161] In this embodiment, the thickness of the first protective film 51a is formed to be sufficiently thick so that the first protective film 51a remains on the first substrate surface 20A at the end of the second dry etching process S5. Furthermore, "residual first protective film 51a" means "at least a portion of the first protective film 51a remains". For example, at the end of the second dry etching process S5, the second metal film 512 of the first metal film 511 and the second metal film 512 constituting the first protective film 51a may also be removed.

[0162] In this embodiment, the first protective film 51a is a metal film formed of metal. Generally, the etching rate of metal is lower than that of the photosensitive resin used as the resist material. Therefore, by making the first protective film 51a a metal film, its thickness can be reduced compared to a resin film. This improves the dimensional accuracy of the first vibrating arm 22 and the second vibrating arm 23, the first grooves 221 and 231, etc., formed in the first dry etching process S3.

[0163] Additionally, a first metal film 511, serving as a fifth protective film 55, is formed in the first trench forming region Q1 on the first substrate surface 20A. A first metal film 511, serving as a seventh protective film 57, is formed in the inter-arm region Q4 and inter-element region Q5 on the first substrate surface 20A. The thickness of the first metal film 511, serving as the fifth protective film 55 and the seventh protective film 57, is thinner than that of the first protective film 51a.

[0164] <<First Dry Etching Process S3>>

[0165] like Figure 19 As shown, the quartz substrate 20 is dry-etched from the first substrate surface 20A side via the first protective film 51a.

[0166] In this embodiment, dry etching begins with a first metal film 511 formed in the first trench forming region Q1, the inter-arm region Q4, and the inter-element region Q5 on the first substrate surface 20A. The first metal film 511 formed in the first trench forming region Q1 as the fifth protective film 55 and the first metal film 511 formed in the inter-arm region Q4 and the inter-element region Q5 as the seventh protective film 57 are thinner than the first protective film 51a formed in the first embankment forming region Qd1. Therefore, the fifth protective film 55 and the seventh protective film 57 are easier to remove in the first dry etching step S3 compared to the first protective film 51a.

[0167] Therefore, even when the first metal film 511, which serves as the fifth protective film 55, is formed in the first groove forming region Q1, the shapes of the first grooves 221 and 231 and the vibrating substrate 2 can be formed simultaneously. Therefore, the process of removing the first metal film 511, which serves as the fifth protective film 55, is not required, and the manufacturing process of the vibrating substrate 2 can be reduced.

[0168] Furthermore, even when the first metal film 511, which serves as the seventh protective film 57, is formed in the inter-arm region Q4 and the inter-element region Q5, the shapes of the first grooves 221 and 231 and the vibrating substrate 2 can be formed simultaneously. Therefore, the process of removing the first metal film 511, which serves as the seventh protective film 57, is not required, and the manufacturing process of the vibrating substrate 2 can be reduced.

[0169] When the first dry etching process S3 is completed, the process moves to the second protective film formation process S4.

[0170] The second protective film formation process S4, the second dry etching process S5, the first protective film removal process S6, and the second protective film removal process S7 are the same as in Embodiment 1, so the description is omitted and will be explained from the third protective film formation process S8.

[0171] <<Third protective film formation process S8>>

[0172] This process is performed in the same manner as the first protective film formation process S2.

[0173] like Figure 20 As shown, firstly, a third metal film 611 is formed on the second substrate surface 20B of the quartz substrate 20. Next, a second resist film (not shown) is formed. The second resist film is patterned such that a fourth metal film 612 can be formed in the second embankment forming region Qd2. Then, using the second resist film as a mask, the fourth metal film 612 is stacked on the third metal film 611. Thus, a third protective film 61a having the third metal film 611 and the fourth metal film 612 is formed in the second embankment forming region Qd2 of the second substrate surface 20B.

[0174] After the third protective film 61a is formed, the second resist film is removed.

[0175] In this embodiment, the thickness of the third protective film 61a is formed to be sufficiently thick so that the third protective film 61a remains on the second substrate surface 20B at the end of the fourth dry etching process S11. Furthermore, "residual third protective film 61a" means "at least a portion of the third protective film 61a remains." For example, at the end of the fourth dry etching process S11, the fourth metal film 612, which constitutes the third protective film 61a, may also be removed.

[0176] In this embodiment, the third protective film 61a is a metal film formed of metal. Therefore, compared with a resin film, the thickness of the third protective film 61a can be reduced. As a result, the dimensional accuracy of the first vibrating arm 22 and the second vibrating arm 23, the second grooves 222 and 232, etc., formed in the third dry etching process S9 can be improved.

[0177] Additionally, a third metal film 611, serving as a sixth protective film 65, is formed in the second trench forming region Q6 on the second substrate surface 20B. A third metal film 611, serving as an eighth protective film 67, is formed in the inter-arm region Q4 and inter-element region Q5 on the second substrate surface 20B. The thickness of the third metal film 611, serving as the sixth protective film 65 and the eighth protective film 67, is thinner than that of the third protective film 61a.

[0178] <<Third Dry Etching Process S9>>

[0179] This process is performed in the same way as the first dry etching process S3.

[0180] like Figure 21 As shown, the quartz substrate 20 is dry-etched from the second substrate surface 20B side through the third protective film 61a.

[0181] In this embodiment, dry etching begins with a third metal film 611 formed in the second trench forming region Q6, the inter-arm region Q4, and the inter-element region Q5 on the second substrate surface 20B. The thickness of the third metal film 611 formed in the second trench forming region Q6 as the sixth protective film 65, and the thickness of the third metal film 611 formed in the inter-arm region Q4 and the inter-element region Q5 as the eighth protective film 67, are thinner than the thickness of the third protective film 61a formed in the second embankment forming region Qd2. Therefore, the sixth protective film 65 and the eighth protective film 67 are easier to remove in the third dry etching step S9 compared to the third protective film 61a.

[0182] Therefore, even when the third metal film 611, which serves as the sixth protective film 65, is formed in the second groove forming region Q6, the shapes of the second grooves 222 and 232 and the vibrating substrate 2 can be formed simultaneously. Therefore, the process of removing the third metal film 611, which serves as the sixth protective film 65, is not required, and the manufacturing process of the vibrating substrate 2 can be reduced.

[0183] Furthermore, even when the third metal film 611, which serves as the eighth protective film 67, is formed in the inter-arm region Q4 and the inter-element region Q5, the shapes of the second grooves 222 and 232 and the vibrating substrate 2 can be formed simultaneously. Therefore, the process of removing the third metal film 611, which serves as the eighth protective film 67, can be eliminated, thus reducing the number of manufacturing steps for the vibrating substrate 2.

[0184] When the third dry etching process S9 ends, the process moves to the fourth protective film formation process S10.

[0185] The fourth protective film formation process S10, the fourth dry etching process S11, the third protective film removal process S12, the fourth protective film removal process S13, and the electrode formation process S14 are the same as in Embodiment 1, so the description is omitted.

[0186] Thus, vibration element 1 is obtained.

[0187] According to this embodiment, in addition to the effects of embodiment 1, the following effects can also be obtained.

[0188] By making the first protective film 51a and the third protective film 61a, which are formed in the first embankment forming region Qd1 and the second embankment forming region Qd2 respectively, into metal films, the dimensional accuracy of the first vibrating arm 22 and the second vibrating arm 23, and the first grooves 221, 231 and the second grooves 222, 232, etc., can be improved.

[0189] The manufacturing method of the vibration element 1 has been described above according to Embodiments 1 and 2. However, the present invention is not limited thereto, and the structure of each part can be replaced with any structure having the same function. In addition, other arbitrary components can be added to the present invention. Furthermore, the embodiments can be appropriately combined.

[0190] For example, at least one of the first protective film 51, the second protective film 52, the third protective film 61 and the fourth protective film 62 may be a resin film.

[0191] Alternatively, for example, at least one of the first protective film 51, the second protective film 52, the third protective film 61, and the fourth protective film 62 may be a metal film.

[0192] Furthermore, for example, a seventh protective film 57 may be formed in the interarm region Q4 of the first substrate surface 20A, while an eighth protective film 67 may not be formed in the interarm region Q4 of the second substrate surface 20B. Alternatively, the seventh protective film 57 may not be formed in the interarm region Q4 of the first substrate surface 20A, while the eighth protective film 67 may be formed in the interarm region Q4 of the second substrate surface 20B. That is, at least one of the interarm regions Q4 of the first substrate surface 20A and the interarm regions Q4 of the second substrate surface 20B may be exposed. In other words, at least one of the interarm regions Q4 of the first substrate surface 20A and the interarm regions Q4 of the second substrate surface 20B may not have a protective film formed.

[0193] Alternatively, for example, a seventh protective film 57 may be formed in the inter-component region Q5 of the first substrate surface 20A, while an eighth protective film 67 may not be formed in the inter-component region Q5 of the second substrate surface 20B. Alternatively, the seventh protective film 57 may not be formed in the inter-component region Q5 of the first substrate surface 20A, while the eighth protective film 67 may be formed in the inter-component region Q5 of the second substrate surface 20B. That is, at least one of the inter-component region Q5 of the first substrate surface 20A and the inter-component region Q5 of the second substrate surface 20B may be exposed. In other words, at least one of the inter-component region Q5 of the first substrate surface 20A and the inter-component region Q5 of the second substrate surface 20B may not have a protective film formed.

[0194] Furthermore, the vibration element manufactured by the manufacturing method of the vibration element of the present invention is not particularly limited.

[0195] The vibration element manufactured by the method of manufacturing the vibration element of the present invention may be, for example, a vibrating element. Figure 22 and Figure 23 The double tuning fork type vibrating element 7 is shown. Additionally, in... Figure 22 and Figure 23The electrodes are omitted from the diagram. The double tuning fork type vibrating element 7 has a pair of bases 711 and 712 and a first vibrating arm 72 and a second vibrating arm 73 connecting the bases 711 and 712. In addition, the first vibrating arm 72 and the second vibrating arm 73 have a first groove 721 and 731 with a bottom that opens on the first surface 7A, a second groove 722 and 732 with a bottom that opens on the second surface 7B, a first embankment 725 and 735 that defines the first groove 721 and 731, and a second embankment 726 and 736 that defines the second groove 722 and 732.

[0196] Alternatively, for example, the vibrating element can also be Figure 24 , Figure 25 as well as Figure 26 The gyroscope oscillating element 8 is shown. Additionally, in... Figure 24 , Figure 25 as well as Figure 26 The electrodes are omitted from the diagram. The gyroscope vibration element 8 has a base 81, a pair of detection vibration arms 82 and 83 extending from the base 81 in the Y direction, a pair of connecting arms 84 and 85 extending from the base 81 in the X direction, drive vibration arms 86 and 87 extending from the front end of the connecting arm 84 in the Y direction, and drive vibration arms 88 and 89 extending from the front end of the connecting arm 85 in the Y direction. In this gyroscope vibration element 8, when the drive vibration arms 86, 87, 88, and 89 are directed towards... Figure 24 When the angular velocity ωz about the Z-axis is applied under the bending vibration state in the direction of arrow SD, the detection vibration arms 82 and 83 are re-excited to bend in the direction of arrow SS by the Coriolis force, and the angular velocity ωz is detected based on the charge output from the detection vibration arms 82 and 83 through this bending vibration.

[0197] In addition, the detection vibration arms 82 and 83 have a first groove 821 and 831 with a bottom that opens on the first surface 8A, a second groove 822 and 832 with a bottom that opens on the second surface 8B, a first embankment 825 and 835 that delineates the first groove 821 and 831, and a second embankment 826 and 836 that delineates the second groove 822 and 832. Furthermore, the driving vibration arms 86, 87, 88, and 89 have bottomed first grooves 861, 871, 881, 891, and 891 with openings on the first surface 8A; bottomed second grooves 862, 872, 882, and 892 with openings on the second surface 8B; first embankments 865, 875, 885, and 895 dividing the first grooves 861, 871, 881, and 891; and second embankments 866, 876, 886, and 896 dividing the second grooves 862, 872, 882, and 892. In this gyroscope vibration element 8, for example, the driving vibration arms 86 and 88 or the driving vibration arms 87 and 89 become the first vibration arm and the second vibration arm.

[0198] Alternatively, for example, the vibrating element can also be Figure 27 , Figure 28 and Figure 29 The gyroscope oscillating element 9 is shown. Additionally, in... Figure 27 , Figure 28 and Figure 29 The electrodes are omitted from the diagram. The gyroscope vibration element 9 has a base 91, a pair of driving vibration arms 92 and 93 extending from the base 91 in the positive Y direction and arranged in the X direction, and a pair of detection vibration arms 94 and 95 extending from the base 91 in the negative Y direction and arranged in the X direction. In this gyroscope vibration element 9, when the driving vibration arms 92 and 93 are directed towards... Figure 27 When the angular velocity ωy around the Y-axis is applied under the bending vibration state in the direction of arrow SD, the bending vibration in the direction of arrow SS is re-excited on the detection vibration arms 94 and 95 by the Coriolis force, and the angular velocity ωy is detected based on the charge output from the detection vibration arms 94 and 95 through this bending vibration.

[0199] Furthermore, the driving vibration arms 92 and 93 have a first groove 921 and 931 with a bottom that opens on the first surface 9A, a second groove 922 and 932 with a bottom that opens on the second surface 9B, a first embankment 925 and 935 that delineates the first groove 921 and 931, and a second embankment 926 and 936 that delineates the second groove 922 and 932. Additionally, the detection vibration arms 94 and 95 have a first groove 941 and 951 with a bottom that opens on the first surface 9A, a second groove 942 and 952 with a bottom that opens on the second surface 9B, a first embankment 945 and 955 that delineates the first groove 941 and 951, and a second embankment 946 and 956 that delineates the second groove 942 and 952. In this gyroscope vibration element 9, the driving vibration arms 92 and 93 or the detection vibration arms 94 and 95 become the first vibration arm and the second vibration arm, respectively.

Claims

1. A method for manufacturing a vibrating element, the vibrating element having a first vibrating arm and a second vibrating arm extending along a first direction and arranged along a second direction intersecting the first direction, the first vibrating arm and the second vibrating arm each having a first surface and a second surface, a first groove with a bottom opening on the first surface and a second groove with a bottom opening on the second surface, the first surface and the second surface being arranged in a positive-negative relationship in a third direction intersecting the first direction and the second direction. The manufacturing method includes: Preparation process: Prepare a quartz substrate with a first substrate surface and a second substrate surface that are in a positive and negative relationship. In the first protective film forming process, a first protective film is formed in the areas of the first vibration arm forming area where the first vibration arm is formed and the second vibration arm forming area where the second vibration arm is formed, excluding the area where the first groove is formed. The first dry etching process involves dry etching the quartz substrate from the side of the first substrate through the first protective film to form the shape of the first groove, the first vibrating arm, and the second vibrating arm. The process ends when the depth of the first groove reaches the first depth. The second protective film forming process involves forming a second protective film in the first groove; In the second dry etching process, the quartz substrate is dry etched from the first substrate side through the second protective film to form the first surface, and the outline is formed until the depth of the outline of the first vibrating arm and the second vibrating arm formed in the first dry etching process becomes a second depth that is deeper than the first depth. In the third protective film forming process, a third protective film is formed in the areas of the first vibration arm forming area and the second vibration arm forming area on the second substrate surface, excluding the second groove forming area where the second groove is formed. The third dry etching process involves dry etching the quartz substrate from the side of the second substrate through the third protective film to form the second groove and the shapes of the first and second vibrating arms. The process ends when the depth of the second groove reaches the third depth. The fourth protective film forming process involves forming a fourth protective film in the second groove. as well as In the fourth dry etching process, the quartz substrate is dry etched from the second substrate side through the fourth protective film to form the second surface, and the shape is formed until the depth of the shape of the first vibrating arm and the second vibrating arm formed in the third dry etching process becomes a fourth depth that is deeper than the third depth.

2. The method for manufacturing a vibrating element according to claim 1, wherein, At least one of the first protective film, the second protective film, the third protective film, and the fourth protective film is a resin film.

3. The method for manufacturing a vibrating element according to claim 1, wherein, At least one of the first protective film, the second protective film, the third protective film, and the fourth protective film is a metal film.

4. The method for manufacturing a vibrating element according to any one of claims 1 to 3, wherein, In the first protective film forming process, a fifth protective film with a thickness thinner than the first protective film is formed in the first groove forming region. In the third protective film forming process, a sixth protective film with a thickness thinner than the third protective film is formed in the second groove forming area.

5. A method for manufacturing a vibrating element according to any one of claims 1 to 3, wherein, In the first protective film forming process, a seventh protective film with a thickness thinner than the first protective film is formed in the inter-arm region on the first substrate surface located between the first vibrating arm forming region and the second vibrating arm forming region. In the third protective film forming process, an eighth protective film with a thickness thinner than the third protective film is formed in the interarm region on the second substrate surface.

6. A method for manufacturing a vibrating element according to any one of claims 1 to 3, wherein, At least one of the inter-arm region located between the first vibration arm forming region and the second vibration arm forming region on the first substrate surface and the inter-arm region on the second substrate surface is not formed with a protective film.

7. A method for manufacturing a vibrating element according to any one of claims 1 to 3, wherein, In the second dry etching process, the dry etching is completed while the first protective film remains on the surface of the first substrate. The manufacturing method further includes a first removal step to remove any residue of the first protective film.

8. The method for manufacturing a vibrating element according to claim 7, wherein, In the fourth dry etching process, the dry etching is completed while the third protective film remains on the surface of the second substrate. The manufacturing method further includes a second removal step to remove any residue of the third protective film.

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