Manufacturing method of vibrating element

Abstract

A method for manufacturing a vibrating element. This method allows for the simultaneous formation of the shape and groove. The method includes: a first protective film formation step, forming a first protective film on a first substrate surface of a quartz substrate; a first dry etching step, performing dry etching from the first substrate surface side to form a first groove and the shapes of a first vibrating arm and a second vibrating arm; a second protective film formation step, forming a second protective film on a second substrate surface of the quartz substrate; and a second dry etching step, performing dry etching from the second substrate surface side to form a second groove and the shapes of the first and second vibrating arms. In the first dry etching step, the shapes of the first and second vibrating arms are formed closer to the second substrate surface side than the position where the bottom surface of the second groove is formed.

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 a method for manufacturing a vibrating element, the vibrating element has 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 and second vibrating arms 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 and second directions. The manufacturing method includes: a preparation step of 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 of forming a first protective film on the first substrate surface; and a first drying step. The etching process involves dry etching the quartz substrate from the first substrate surface side through the first protective film to form the first surface, the first groove, and the outlines of the first and second vibrating arms; the second protective film formation process involves forming a second protective film on the second substrate surface; and the second dry etching process involves dry etching the quartz substrate from the second substrate surface side through the second protective film to form the second surface, the second groove, and the outlines of the first and second vibrating arms. In the first dry etching process, the outlines of the first and second vibrating arms are formed closer to the second substrate surface side than the position where the bottom surface of the second groove is formed in the third direction. 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 5 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0015] Figure 6 This is a diagram showing the formation process of the first protective film.

[0016] Figure 7 This is a cross-sectional view used to illustrate the method of forming the first protective film.

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

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

[0019] Figure 10 This is a diagram showing the process of forming the second protective film.

[0020] Figure 11 This is a cross-sectional view used to illustrate the method of forming the second protective film.

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

[0024] Figure 15 This is a cross-sectional view used to illustrate the manufacturing method of the vibration element in Embodiment 3.

[0025] Figure 16 This is a diagram showing the formation process of the first protective film.

[0026] Figure 17 This is a cross-sectional view used to illustrate the method of forming the first protective film.

[0027] Figure 18 This is a cross-sectional view used to illustrate the method of forming the first protective film.

[0028] Figure 19 This is a cross-sectional view used to illustrate the method of forming the first protective film.

[0029] Figure 20 This is a cross-sectional view used to illustrate the method of forming the first protective film.

[0030] Figure 21 This is a cross-sectional view used to illustrate the method of forming the first protective film.

[0031] Figure 22 This is a cross-sectional view used to illustrate the method of forming the first protective film.

[0032] Figure 23 This is a cross-sectional view used to illustrate the method of forming the first protective film.

[0033] Figure 24 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0034] Figure 25 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0035] Figure 26This is a diagram showing the process of forming the second protective film.

[0036] Figure 27 This is a cross-sectional view used to illustrate the method of forming the second protective film.

[0037] Figure 28 This is a cross-sectional view used to illustrate the method of forming the second protective film.

[0038] Figure 29 This is a cross-sectional view used to illustrate the method of forming the second protective film.

[0039] Figure 30 It is a cross-sectional view used to illustrate the manufacturing method of a vibrating element.

[0040] Figure 31 This is a top view showing a modified example of the vibrating element.

[0041] Figure 32 yes Figure 31 Sectional view along line A3-A3 in the diagram.

[0042] Figure 33 This is a top view showing a modified example of the vibrating element.

[0043] Figure 34 yes Figure 33 Sectional view along line A4-A4 in the diagram.

[0044] Figure 35 yes Figure 33 Sectional view along line A5-A5.

[0045] Figure 36 This is a top view showing a modified example of the vibrating element.

[0046] Figure 37 yes Figure 36 Sectional view along line A6-A6 in the diagram.

[0047] Figure 38 yes Figure 36 Sectional view along line A7-A7 in the diagram.

[0048] Label Explanation

[0049] 1. Vibrating element; 2. Vibrating substrate; 2A. First surface; 2B. Second surface; 5, 5b. First protective film; 6, 6b. Second protective film; 20. Quartz substrate; 20A. First substrate surface; 20B. Second substrate surface; 21. Base; 22. First vibrating arm; 23. Second vibrating arm; 51. First base film; 53. Third protective film; 61. Second base film; 63. Fourth protective film; 221, 231. First groove; 222, 232. Second groove; 222A, 232A. Bottom surface; 225, 235. First embankment; 226, 236. Second embankment; Q1. First groove forming area; Q2. First vibrating arm forming area. Q3 Second vibrating arm forming area; Q4 Inter-arm area; Q5 Inter-element area; Q6 Second trench forming area; Qd1 First embankment forming area; Qd2 Second embankment forming area; S1 Preparation process; S2 First protective film forming process; S3 First dry etching process; S4 First protective film removal process; S5 Second protective film forming process; S6 Second dry etching process; S7 Second protective film removal process; S8 Electrode forming process; S100 First base film forming process; S110 Third protective film forming process; S120 Second base film forming process; S130 Fourth protective film forming process. Detailed Implementation

[0050] Next, embodiments of the present invention will be described with reference to the accompanying drawings.

[0051] For ease of explanation, except Figure 3 , Figure 6 , Figure 10 , Figure 16 as well as Figure 26 In the figures other than those shown, the X-axis, Y-axis, and Z-axis are depicted as three mutually orthogonal axes. The direction along the X-axis is referred to as the "X-direction," the direction along the Y-axis as the "Y-direction," and the direction along the Z-axis as the "Z-direction." Furthermore, the front end of the arrow in each direction is referred to as the "positive side," and the base end as the "negative side." For example, the Y-direction includes both the positive and negative sides. The positive side of the Z-direction is referred to as "up," and the negative side as "down." The view from the Z-direction is simply referred to as "top view." The thickness along the Z-direction is simply referred to as "thickness." The Y-direction is referred to as the "first direction," the X-direction as the "second direction," and the Z-direction as the "third direction." In this embodiment, as described later, the X-axis, Y-axis, and Z-axis correspond to the crystal axes of quartz.

[0052] 1. Implementation Method 1

[0053] The manufacturing method of the vibration element 1 in Embodiment 1 will be described.

[0054] First, refer to Figure 1 and Figure 2The structure of vibrating element 1 will be explained, and then, referring to... Figures 3 to 13 The manufacturing method of vibration element 1 is explained.

[0055] 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.

[0056] 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 and Y axes as 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.

[0057] 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.

[0058] 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 a portion arranged along the X direction on the first surface 2A, separated by the first groove 221, when viewed from above. The second embankment 226 is a portion arranged along the X direction on the second surface 2B, separated by the second groove 222, when viewed from above.

[0059] The second vibrating arm 23 has: a first groove 231 with a bottom that opens on the first surface 2A; a first embankment 235 that defines the first groove 231; a second groove 232 with a bottom that opens on the second surface 2B; a second embankment 236 that defines the second groove 232; and a side surface 103 connecting the first surface 2A and the second surface 2B. The first embankment 235 is a portion arranged along the X direction on the first surface 2A, separated by the first groove 231, when viewed from above. The second embankment 236 is a portion arranged along the X direction on the second surface 2B, separated by the second groove 232, when viewed from above.

[0060] 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.

[0061] 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.

[0062] The above provides a brief description of the vibrating element 1.

[0063] Next, the manufacturing method of the vibrating element 1 will be described.

[0064] like Figure 3 As 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 forming step S2, forming a first protective film 5 on the first substrate surface 20A of the quartz substrate 20; a first dry etching step S3, dry etching the quartz substrate 20 from the first substrate surface 20A side through the first protective film 5; a first protective film removal step S4, removing the first protective film 5 remaining on the first substrate surface 20A of the quartz substrate 20; a second protective film forming step S5, forming a second protective film 6 on the second substrate surface 20B of the quartz substrate 20; a second dry etching step S6, dry etching the quartz substrate 20 from the second substrate surface 20B side through the second protective film 6; a second protective film removal step S7, removing the second protective film 6 remaining on the second substrate surface 20B of the quartz substrate 20; and an electrode forming step S8, forming an electrode 3 on the surface of the vibrating substrate 2 obtained through the above steps.

[0065] Furthermore, in this embodiment, in the first dry etching process S3, the shapes of the first vibrating arm 22 and the second vibrating arm 23 are formed closer to the second substrate surface 20B side than the position of the bottom surface forming the second groove 222, 232 in the Z direction.

[0066] The following sections will explain each of these processes in turn.

[0067] <<Preparation Process S1>>

[0068] like Figure 4As shown, a quartz substrate 20 is prepared as the parent material for the vibrating substrate 2. A plurality of 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. In this embodiment, the first substrate surface 20A is the upper surface of the quartz substrate 20, and the second substrate surface 20B is the lower surface of the quartz substrate 20.

[0069] The quartz substrate 20 is adjusted to the desired thickness through grinding or polishing processes, and the first substrate surface 20A and the second substrate surface 20B are sufficiently smoothed. Alternatively, the quartz substrate 20 may be subjected to a surface treatment based on wet etching as needed.

[0070] 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.

[0071] 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 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.

[0072] 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 embankment portions 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.

[0073] <<First Protective Film Forming Process S2>>

[0074] like Figure 5 As shown, a first protective film 5 is formed on the first substrate surface 20A of the quartz substrate 20.

[0075] The first protective film 5 has a thin region along the Z direction and a thick region along the Z direction. The first protective film 5 is formed from a material etched at a specified etching rate in the first dry etching process S3 described later.

[0076] In the subsequent first dry etching step S3, the quartz substrate 20 is etched from the first substrate surface 20A side of the quartz substrate 20 through the first protective film 5. That is, after the first protective film 5 is removed, the first substrate surface 20A of the quartz substrate 20 starts to be etched. Therefore, in the region where the thickness of the first protective film 5 is thin, the etching of the quartz substrate 20 starts earlier than in the region where the thickness of the first protective film 5 is thick, so the etching depth becomes deeper. On the other hand, in the region where the thickness of the first protective film 5 is thick, the etching of the quartz substrate 20 starts later than in the region where the thickness of the first protective film 5 is thin, so the etching depth of the quartz substrate 20 becomes shallower. Thus, by adjusting the thickness of the first protective film 5, the etching depth of the quartz substrate 20 can be controlled.

[0077] The first protective film 5 is formed in the first vibrating arm forming region Q2, the second vibrating arm forming region Q3, the inter-arm region Q4, and the inter-element region Q5 of the first substrate surface 20A.

[0078] When the thickness of the first protective film 5 along the Z direction in the inter-arm region Q4 is T1, the thickness of the first protective film 5 along the Z direction in the first groove forming region Q1 is T2, and the thickness of the first protective film 5 along the Z direction in the first bank forming region Qd1 is T3, the thickness of the first protective film 5 along the Z direction satisfies T1 < T2 < T3.

[0079] By forming the first protective film 5 such that the thickness of the first protective film 5 satisfies T1 < T2 < T3, in the subsequent first dry etching step S3, the etching depth of the quartz substrate 20 in the inter-arm region Q4 is deeper than the etching depth of the quartz substrate 20 in the first groove forming region Q1. And the etching depth of the quartz substrate 20 in the first groove forming region Q1 is deeper than the etching depth of the quartz substrate 20 in the first bank forming region Qd1.

[0080] In addition, when the thickness of the first protective film 5 along the Z direction in the inter-element region Q5 is T11, the thickness of the first protective film 5 along the Z direction satisfies T11 < T2 < T3.

[0081] By forming the first protective film 5 such that the thickness of the first protective film 5 satisfies T11 < T2 < T3, in the subsequent first dry etching step S3, the etching depth of the quartz substrate 20 in the inter-element region Q5 is deeper than the etching depth of the quartz substrate 20 in the first groove forming region Q1.

[0082] In the present embodiment, the first protective film 5 in the inter-element region Q5 is formed in the same manner as the first protective film 5 in the inter-arm region Q4. Therefore, the thickness T11 of the first protective film 5 in the inter-element region Q5 is substantially equal to the thickness T1 of the first protective film 5 in the inter-arm region Q4.

[0083] In addition, "approximately equal" is a concept that includes cases where they are not strictly equal due to deviations in manufacturing conditions, etc.

[0084] The method for forming the first protective film 5 is described.

[0085] like Figure 6 As shown, in this embodiment, the first protective film formation process S2 includes: a first coating process S21, which forms a resist film by coating a resist material on the first substrate surface 20A of the quartz substrate 20; a first exposure process S22, which exposes the resist film formed on the first substrate surface 20A; and a first development process S23, which develops the resist film formed on the first substrate surface 20A.

[0086] like Figure 7 As shown, in the first coating process S21, a first resist film R1 is formed on the first substrate surface 20A of the quartz substrate 20. The first resist film R1 is a resist film formed of resist material. The first resist film R1 is formed by coating the first substrate surface 20A with resist material to a predetermined thickness. As a method for coating the resist material, spin coating or spray coating can be used, for example.

[0087] In this embodiment, the photoresist material is a positive photoresist. Alternatively, the photoresist material can also be negative.

[0088] Next, in the first exposure process S22, electromagnetic waves L1 are irradiated onto the first resist film R1 formed on the first substrate surface 20A. The electromagnetic waves L1 irradiate the first resist film R1 with an exposure intensity E corresponding to each region of the inter-arm region Q4, the first trench forming region Q1, the first embankment forming region Qd1, and the inter-element region Q5. Figure 7 This illustrates an example of the distribution of the exposure intensity E of electromagnetic wave L1 in the X direction. The exposure intensity E of electromagnetic wave L1 can be altered using filters or grayscale masks.

[0089] Next, in the first development step S23, the first resist film R1 formed on the first substrate surface 20A is developed. The thickness of the first protective film 5 is the thickness corresponding to the exposure intensity E of the electromagnetic wave L1 that irradiates the first resist film R1 in the first exposure step S22.

[0090] Thus, forming Figure 5 The first protective film 5 is shown.

[0091] In this embodiment, the first protective film 5 is formed from the first resist film R1. Therefore, the first protective film 5 can be easily formed.

[0092] Furthermore, the method for forming the first protective film 5 is not limited to the methods described above. For example, the first protective film 5 can also be formed using printing techniques such as embossing.

[0093] Furthermore, the first protective film 5 is not limited to a resist film formed from a resist material. For example, the first protective film 5 can also be a metal film formed from metals such as nickel, copper, and chromium. Such a metal film can be formed, for example, by electroplating. Generally, the etching rate of metal is lower than that of the photoresist used in the resist material. Therefore, by making the first protective film 5 a metal film, its thickness can be reduced compared to a resist film. As a result, 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 can be improved.

[0094] <<First Dry Etching Process S3>>

[0095] like Figure 8 As shown, the quartz substrate 20 is dry-etched from the first substrate surface 20A side through the first protective film 5, simultaneously forming the shape of the first surface 2A, the first grooves 221 and 231, and the vibrating substrate 2. "Simultaneously formed" means formed together in one process. That is, in the first dry etching process S3, the shape of the first surface 2A, the first grooves 221 and 231, and the vibrating substrate 2 are formed together.

[0096] More specifically, this process is reactive ion etching, performed using a reactive ion etching apparatus (RIE apparatus). Furthermore, there are no particular limitations on the reactive gas introduced into the RIE apparatus; for example, SF6, CF4, C2F4, C2F6, C3F6, C4F8, etc., can be used.

[0097] The first protective film 5, formed on the first substrate surface 20A of the quartz substrate 20, is etched at a predetermined etching rate in the first dry etching step S3. Then, by removing the first protective film 5, the first substrate surface 20A is exposed, and etching of the quartz substrate 20 begins. Therefore, by adjusting the thickness of the first protective film 5, the etching depth of the quartz substrate 20 can be controlled. Furthermore, by making the thickness of the first protective film 5 sufficiently thick, the first dry etching step S3 can be ended while the first protective film 5 remains on the first substrate surface 20A, preventing the first substrate surface 20A from being etched.

[0098] The first dry etching process S3 ends when the first trenches 221 and 231 reach the desired depth. The etching depth of the quartz substrate 20 in the first trench formation region Q1 is the depth Wa of the first trenches 221 and 231. The etching depth of the quartz substrate 20 in the inter-arm region Q4 is the depth Aa of the outer shape of the vibrating substrate 2. The etching depth of the quartz substrate 20 in the inter-component region Q5 is the depth Ba of the outer shape of the vibrating substrate 2.

[0099] As described above, the thickness T1 of the first protective film 5 in the inter-arm region Q4 and the thickness T11 of the first protective film 5 in the inter-element region Q5 are thinner than the thickness T2 of the first protective film 5 in the first groove formation region Q1. That is, T1 < T2 and T11 < T2. Therefore, the depths Aa and Ba of the outer shape of the vibrating substrate 2 are deeper than the depths Wa of the first grooves 221 and 231. That is, Wa < Aa and Wa < Ba.

[0100] In addition, as described above, the thickness T2 of the first protective film 5 in the first groove formation region Q1 is thinner than the thickness T3 of the first protective film 5 in the first bank formation region Qd1. That is, T2 < T3. Therefore, the depths Wa of the first grooves 221 and 231 are deeper than the etching depth of the quartz substrate 20 in the first bank formation region Qd1.

[0101] In this way, in the first dry etching process S3, by dry-etching the quartz substrate 20 from the first substrate surface 20A side隔着 the first protective film 5, the outer shapes of the first vibrating arm 22 and the second vibrating arm 23 and the first grooves 221 and 231 can be formed together.

[0102] According to dry etching, processing can be performed without being affected by the crystal plane of quartz. Therefore, the first grooves 221 and 231 and the outer shape of the vibrating substrate 2 can be formed with excellent dimensional accuracy.

[0103] In addition, by forming the first grooves 221 and 231 and the outer shape of the vibrating substrate 2 together, reduction of the manufacturing process of the vibrating element 1 and cost reduction of the vibrating element 1 can be achieved. In addition, the positional deviation of the first grooves 221 and 231 relative to the outer shape is prevented, so that the formation accuracy of the vibrating substrate 2 can be improved.

[0104] And, by forming the first protective film 5 in such a manner that the thickness of the first protective film 5 satisfies T1 < T2 < T3 and T11 < T2 < T3, in the first dry etching process S3, the outer shapes of the first vibrating arm 22 and the second vibrating arm 23 and the first grooves 221 and 231 can be formed together without using the microloading effect.

[0105] Since the microloading effect is not used, there is no restriction on the setting of 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, and the design freedom of the vibrating element 1 can be improved. For example, in the first protective film formation process S2, by adjusting the thickness or width of the first protective film 5, the outer dimensions of the first grooves 221 and 231, the first vibrating arm 22, and the second vibrating arm 23 can be controlled.

[0106] In addition, since the microloading effect is not utilized, the constraints on dry etching conditions such as the selection of reaction gases used in dry etching are alleviated. Therefore, compared with the case where the microloading effect is utilized, the vibration element 1 can be easily manufactured.

[0107] Further, in the present embodiment, the depths Aa and Ba of the outer shape of the vibration substrate 2 are deeper than the difference Ta - Wb between the thickness Ta of the quartz substrate 20 and the depths Wb of the second grooves 222 and 232 formed in the second dry etching process S6 described later. That is, Ta - Wb < Aa, Ta - Wb < Ba.

[0108] Ta - Wb, which is the difference between the thickness Ta of the quartz substrate 20 and the depths Wb of the second grooves 222 and 232, corresponds to the distance in the Z direction from the first substrate surface 20A of the quartz substrate 20 to the bottom surfaces 222A and 232A of the second grooves 222 and 232.

[0109] That is, Ta - Wb < Aa, Ta - Wb < Ba means that the depths Aa and Ba of the outer shape of the vibration substrate 2 are deeper than the positions of the bottom surfaces 222A and 232A of the second grooves 222 and 232.

[0110] In other words, in the first dry etching process S3, the outer shapes of the first vibration arm 22 and the second vibration arm 23 are formed closer to the second substrate surface 20B side than the positions of the bottom surfaces 222A and 232A of the second grooves 222 and 232 in the Z direction.

[0111] Thus, in the first dry etching process S3, the outer shapes of the first vibration arm 22 and the second vibration arm 23 are formed closer to the second substrate surface 20B side than the positions of the bottom surfaces 222A and 232A of the second grooves 222 and 232 in the Z direction. Thereby, in the second protective film forming process S5 described later, the second protective film 6 is not formed in the second groove forming region Q6 of the second substrate surface 20B, and in the second dry etching process S6 described later, the second grooves 222 and 232 can be formed.

[0112] In addition, in the present embodiment, the thickness T1 of the first protective film 5 in the arm - to - arm region Q4 and the thickness T11 of the first protective film 5 in the element - to - element region Q5 satisfy 0 < T1, 0 < T11.

[0113] By making 0 < T1, 0 < T11, even when there is a deviation in the thickness of the first resist film R1, the difference in depth between the depths Aa and Ba of the outer shape of the vibration substrate 2 and the depth Wa of the first grooves 221 and 231 can be made to be a substantially constant depth.

[0114] According to the deviation in the thickness of the first resist film R1, the thicknesses T1 and T11 of the first protective film 5 in the inter-arm region Q4 and the inter-element region Q5 and the thickness T2 of the first protective film 5 in the first groove formation region Q1 deviate respectively. However, by setting 0 < T1 and 0 < T11, the difference between the thicknesses T1 and T11 of the first protective film 5 in the inter-arm region Q4 and the inter-element region Q5 and the thickness T2 of the first protective film 5 in the first groove formation region Q1 is kept substantially constant. That is, the time difference between the time when the etching of the quartz substrate 20 starts in the inter-arm region Q4 and the inter-element region Q5 and the time when the etching of the quartz substrate 20 starts in the first groove formation region Q1 is a substantially constant time. Therefore, the difference between the depths Aa and Ba of the outer shape of the vibrating substrate 2 and the depths Wa of the first grooves 221 and 231 can be set to a substantially constant depth.

[0115] In addition, in the present embodiment, by making the thickness T3 of the first protective film 5 in the first bank formation region Qd1 thick enough, in the first dry etching step S3, the dry etching ends with the first protective film 5 remaining in the first bank formation region Qd1 of the first substrate surface 20A. That is, the first bank formation region Qd1 of the first substrate surface 20A is protected by the first protective film 5 and is not etched in the first dry etching step S3. In the first protective film removal step S4 described later, the first bank formation region Qd1 of the first substrate surface 20A becomes the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23.

[0116] Further, by adjusting the thickness T3 of the first protective film 5 in the first bank formation region Qd1, in the first dry etching step S3, the dry etching can also end with the first protective film 5 not remaining in the first bank formation region Qd1 of the first substrate surface 20A. That is, in the first dry etching step S3, the first bank formation region Qd1 of the first substrate surface 20A can also be etched. In this case, the surface etched in the first dry etching step S3 becomes the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23.

[0117] In this way, in the first dry etching step S3, by etching or not etching the first bank formation region Qd1 of the first substrate surface 20A, the first surface 2A can be formed.

[0118] <<First protective film removal step S4>>

[0119] As Figure 9As shown, the first protective film 5 remaining in the first embankment formation region Qd1 on the first substrate surface 20A is removed. Thus, the first substrate surface 20A of the quartz substrate 20 becomes the first surface 2A of the first vibrating arm 22 and the second vibrating arm 23. That is, 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. Therefore, the thickness of the first vibrating arm 22 and the second vibrating arm 23 in the first embankment formation region Qd1, 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.

[0120] Alternatively, in the first dry etching process S3 described above, if the dry etching is completed in the state where the first protective film 5 does not remain on the first substrate surface 20A of the quartz substrate 20, the first protective film removal process S4 may not be provided.

[0121] After the first protective film removal process S4 is completed, the process is transferred to the second substrate surface 20B of the quartz substrate 20.

[0122] <<Second Protective Film Forming Process S5>>

[0123] like Figure 9 As shown, a second protective film 6 is formed on the second substrate surface 20B of the quartz substrate 20.

[0124] The second protective film 6 is formed in the second embankment forming region Qd2 on the second substrate surface 20B. That is, the second protective film 6 is not formed in the inter-arm region Q4, the inter-element region Q5, and the second trench forming region Q6 on the second substrate surface 20B.

[0125] The second protective film 6 is not formed in the inter-arm region Q4, inter-element region Q5 and second trench formation region Q6 on the second substrate surface 20B. Therefore, in the second dry etching process S6 described later, by performing dry etching, the etching depths of the inter-arm region Q4, inter-element region Q5 and second trench formation region Q6 are approximately equal.

[0126] The method for forming the second protective film 6 is explained.

[0127] like Figure 10 As shown, in this embodiment, the second protective film formation process S5 includes: a second coating process S51, which forms a resist film by coating a resist material on the second substrate surface 20B of the quartz substrate 20; a second exposure process S52, which exposes the resist film formed on the second substrate surface 20B; and a second development process S53, which develops the resist film formed on the second substrate surface 20B.

[0128] like Figure 11As shown, in the second coating process S51, a first resist film R1 is formed on the second substrate surface 20B of the quartz substrate 20. The second coating process S51 is performed in the same manner as the first coating process S21.

[0129] Next, in the second exposure step S52, electromagnetic waves L2 are irradiated onto the first resist film R1 formed on the second substrate surface 20B. In the second development step S53, which will be described later, electromagnetic waves L2 are irradiated in such a way that the first resist film R1 remaining in the second embankment formation region Qd2 is removed, and the first resist film R1 other than the second embankment formation region Qd2 is removed.

[0130] Next, in the second development step S53, the first resist film R1 formed on the second substrate surface 20B is developed. The second development step S53 is performed in the same manner as the first development step S23.

[0131] Thus, forming Figure 9 The second protective film 6 is shown.

[0132] Furthermore, in this embodiment, the second protective film 6 is formed from the first resist film R1. Therefore, the second protective film 6 can be easily formed.

[0133] Furthermore, the method for forming the second protective film 6 is not limited to the methods described above. For example, the second protective film 6 can also be formed using printing techniques such as embossing.

[0134] Furthermore, the second protective film 6 is not limited to a resist film formed of a resist material. For example, the second protective film 6 can also be a metal film formed of metal.

[0135] In this embodiment, the first protective film 5 and the second protective film 6 are resist films, but it is also possible that one of the first protective film 5 and the second protective film 6 is a resist film and the other is a metal film. Alternatively, the first protective film 5 and the second protective film 6 may also be metal films.

[0136] <<Second Dry Etching Process S6>>

[0137] like Figure 12 As shown, the quartz substrate 20 is dry-etched from the second substrate surface 20B side through the second protective film 6, simultaneously forming the second surface 2B, the second grooves 222 and 232, and the outline of the vibrating substrate 2. That is, in the second dry etching process S6, the second surface 2B, the second grooves 222 and 232, and the outline of the vibrating substrate 2 are formed together. Then, the outline of the vibrating substrate 2 is formed, with the inter-arm region Q4 and the inter-element region Q5 respectively penetrating through, thereby forming the first vibrating arm 22 and the second vibrating arm 23. This process is performed in the same manner as the first dry etching process S3.

[0138] The second dry etching process S6 ends when the second trenches 222 and 232 reach the desired depth. The etching depth of the quartz substrate 20 in the second trench formation region Q6 is the depth Wb of the second trenches 222 and 232. The etching depth of the quartz substrate 20 in the inter-arm region Q4 is the depth Ab of the outer shape of the vibrating substrate 2. The etching depth of the quartz substrate 20 in the inter-component region Q5 is the depth Bb of the outer shape of the vibrating substrate 2.

[0139] Thus, in the second dry etching process S6, by dry etching the quartz substrate 20 from the second substrate surface 20B side through the second protective film 6, the shapes of the first vibrating arm 22 and the second vibrating arm 23 and the second grooves 222 and 232 can be formed simultaneously without utilizing the micro-load effect.

[0140] However, in the prior art, when dry etching is performed from the second substrate surface 20B, in order to penetrate the inter-arm region Q4 and the inter-element region Q5 respectively, the etching depth of the inter-arm region Q4 and the inter-element region Q5 is made deeper than the etching depth of the second trench forming region Q6.

[0141] In order to avoid utilizing the micro-load effect so that the etching depth of the inter-arm region Q4 and the inter-component region Q5 is deeper than the etching depth of the second trench forming region Q6, for example, a second protective film 6 can be pre-formed in the second trench forming region Q6 on the second substrate surface 20B to protect the second trench forming region Q6 from being etched.

[0142] On the other hand, in this embodiment, as described above, in the second protective film formation step S5, the second protective film 6 is not formed in the second trench formation region Q6 on the second substrate surface 20B. Specifically, in the second protective film formation step S5, the second protective film 6 is not formed in the inter-arm region Q4, the inter-element region Q5, and the second trench formation region Q6 on the second substrate surface 20B. Therefore, in the second dry etching step S6, by performing dry etching, the depth Wb of the second trenches 222 and 232 is approximately equal to the depths Ab and Bb of the outer shape of the vibrating substrate 2.

[0143] Even when the depth Wb of the second grooves 222 and 232 is approximately equal to the depths Ab and Bb of the outer shape of the vibrating substrate 2, in the first dry etching process S3, the outer shapes of the first vibrating arm 22 and the second vibrating arm 23 are formed closer to the second substrate surface 20B than the positions in the Z direction where the bottom surfaces 222A and 232 of the second grooves 222 and 232 are formed. Therefore, the depths Aa and Ba of the outer shape of the vibrating substrate 2 in the first dry etching process S3 intersect with the depths Ab and Bb of the outer shape of the vibrating substrate 2 in the second dry etching process S6. In this way, even when the depth Wb of the second grooves 222 and 232 is approximately equal to the depths Ab and Bb of the outer shape of the vibrating substrate 2, the inter-arm region Q4 and the inter-element region Q5 can be connected respectively. That is, in this embodiment, in the second dry etching process S6, even if the etching depth of the inter-arm region Q4 and the inter-element region Q5 is not deeper than the etching depth of the second trench forming region Q6, the inter-arm region Q4 and the inter-element region Q5 can still be made to be connected. In other words, in the second protective film forming process S5, even if the second protective film 6 is not formed in the second trench forming region Q6 of the second substrate surface 20B, the outlines of the first vibrating arm 22 and the second vibrating arm 23 and the second trenches 222 and 232 can still be formed together in the second dry etching process S6, and the inter-arm region Q4 and the inter-element region Q5 can be made to be connected.

[0144] Furthermore, in this embodiment, as described above, the second protective film 6 is formed in the second embankment forming region Qd2 on the second substrate surface 20B, but not in the second trench forming region Q6. That is, the second trench forming region Q6 on the second substrate surface 20B is exposed. Therefore, in the second dry etching process S6, the etching of the second trench forming region Q6 begins simultaneously with the start of the dry etching process. In this way, in the second protective film forming process S5, the second protective film 6 can be formed without forming the second trench forming region Q6 on the second substrate surface 20B, while the second trenches 222 and 232 can be formed in the second dry etching process S6. Therefore, the second trenches 222 and 232 can be formed in a short time.

[0145] Furthermore, in this embodiment, as described above, the second protective film 6 is formed in the second embankment forming region Qd2 on the second substrate surface 20B, but not in the inter-arm region Q4 and the inter-device region Q5. That is, the inter-arm region Q4 and the inter-device region Q5 on the second substrate surface 20B are exposed. Therefore, in the second dry etching process S6, the etching of the inter-arm region Q4 and the inter-device region Q5 begins simultaneously with the start of the dry etching process. Therefore, in the second dry etching process S6, the inter-arm region Q4 and the inter-device region Q5 can be penetrated in a short time.

[0146] Furthermore, in this embodiment, by making the thickness of the second protective film 6 in the second embankment formation region Qd2 sufficiently thick, the dry etching process S6 ends when the second protective film 6 remains in the second embankment formation region Qd2 of the second substrate surface 20B. That is, the second embankment formation region Qd2 of the second substrate surface 20B is not etched in the second dry etching process S6. In the second protective film removal process S7 described later, the second embankment formation region Qd2 of the second substrate surface 20B becomes the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23.

[0147] Furthermore, by adjusting the thickness of the second protective film 6 in the second embankment formation region Qd2, the dry etching process S6 can be completed in a state where the second protective film 6 does not remain in the second embankment formation region Qd2 of the second substrate surface 20B. That is, the second embankment formation region Qd2 of the second substrate surface 20B can also be etched in the second dry etching process S6. In this case, the surface etched in the second dry etching process S6 becomes the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23.

[0148] Thus, in the second dry etching process S6, the second surface 2B can be formed by etching or not etching the second embankment forming region Qd2 of the second substrate surface 20B.

[0149] <<Second Protective Film Removal Process S7>>

[0150] like Figure 13 As shown, the second protective film 6 remaining in the second embankment formation region Qd2 on the second substrate surface 20B is removed. Thus, the second substrate surface 20B of the quartz substrate 20 becomes the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23. That is, the second surface 2B of the first vibrating arm 22 and the second vibrating arm 23 is not etched in the second dry etching process S6. Therefore, the thickness of the first vibrating arm 22 and the second vibrating arm 23 in the second embankment formation region Qd2, 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.

[0151] Alternatively, in the second dry etching process S6 described above, if the dry etching is completed without the second protective film 6 remaining on the second substrate surface 20B of the quartz substrate 20, the second protective film removal process S7 may not be provided.

[0152] In addition, in this embodiment, the first protective film 5 remaining on the first substrate surface 20A is removed in the first protective film removal process S4, and the second protective film 6 remaining on the second substrate surface 20B is removed in the second protective film removal process S7. However, the first protective film removal process S4 may be omitted, and the first protective film 5 remaining on the first substrate surface 20A and the second protective film 6 remaining on the second substrate surface 20B may be removed together in the second protective film removal process S7.

[0153] Through the above processes S1 to S7, as follows Figure 13 As shown, multiple vibrating substrates 2 are formed together from the quartz substrate 20.

[0154] <<Electrode Formation Process S8>>

[0155] A metal film is formed on the surface of the vibrating substrate 2, and an electrode 3 is formed by patterning the metal film.

[0156] Thus, vibration element 1 is obtained.

[0157] Furthermore, in this embodiment, the steps are performed in the following order: preparation step S1, first protective film formation step S2, first dry etching step S3, first protective film removal step S4, second protective film formation step S5, second dry etching step S6, second protective film removal step S7, and electrode formation step S8. However, the order of each step S1, S2, S3, S4, S5, S6, S7, and S8 is not limited to this. For example, the order could also be steps S1, S5, S6, S7, S2, S3, S4, and S8.

[0158] As described above, the following effects can be obtained according to this embodiment.

[0159] 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 in the Z direction (a third direction) intersecting the Y and X directions. The manufacturing method includes: a preparation step S1, preparing a quartz substrate 20 having a first substrate surface 20A and a second substrate surface 20B with a positive-negative relationship; and a first protective film forming step S2, forming a first protective film on the first substrate surface 20A. Protective film 5; First dry etching process S3, dry etching is performed on the quartz substrate 20 from the first substrate surface 20A side through the first protective film 5 to form the outline of the first surface 2A, the first grooves 221, 231, the first vibrating arm 22 and the second vibrating arm 23; Second protective film forming process S5, forming the second protective film 6 on the second substrate surface 20B; and Second dry etching process S6, dry etching is performed on the quartz substrate 20 from the second substrate surface 20B side through the second protective film 6 to form the outline of the second surface 2B, the second grooves 222, 232, the first vibrating arm 22 and the second vibrating arm 23; In the first dry etching process S3, the outline of the first vibrating arm 22 and the second vibrating arm 23 is formed in the Z direction closer to the second substrate surface 20B side than the position of the bottom surfaces 222A, 232A where the second grooves 222, 232 are formed.

[0160] 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.

[0161] Furthermore, in the second protective film formation process S5, the second protective film 6 can be formed in the second trench formation region Q6 on the second substrate surface 20B instead of the second protective film 6, and the second trenches 222 and 232 can be formed in the second dry etching process S6. Therefore, the second trenches 222 and 232 can be formed in a short time.

[0162] 2. Implementation Method 2

[0163] Reference Figure 14 The manufacturing method of the vibration element 1 in Embodiment 2 is described below. Furthermore, the same markings are used for structures identical to those in Embodiment 1, and repeated descriptions are omitted.

[0164] In Embodiment 2, in the first protective film 5, T1 = 0 and T11 = 0, otherwise it is the same as in Embodiment 1.

[0165] 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.

[0166] <<First Protective Film Forming Process S2>>

[0167] like Figure 14 As shown, a first protective film 5 is formed on the first substrate surface 20A of the quartz substrate 20. This process is performed in the same manner as in Embodiment 1.

[0168] The thickness of the first protective film 5 satisfies T1 <T2<T3、T11<T2<T3。

[0169] However, in this embodiment, the first protective film 5 is formed in the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 on the first substrate surface 20A, but is not formed in the inter-arm region Q4 and the inter-element region Q5 on the first substrate surface 20A. That is, in the first protective film 5, T1 = 0 and T11 = 0.

[0170] <<First Dry Etching Process S3>>

[0171] This process is performed in the same way as in Implementation Method 1.

[0172] In the first dry etching process S3, the depths Aa and Ba of the shape of the vibrating substrate 2 are formed to be deeper than the difference Ta-Wb between the thickness Ta of the quartz substrate 20 and the depth Wb of the second grooves 222 and 232.

[0173] In this embodiment, the first protective film 5 is not formed in the inter-arm region Q4 and inter-element region Q5 of the first substrate surface 20A during the first protective film formation step S2. Therefore, in the first dry etching step S3, the etching of the quartz substrate 20 in the inter-arm region Q4 and inter-element region Q5 begins simultaneously with the start of dry etching. Thus, the first dry etching step S3 can be performed in a shorter time.

[0174] When the first dry etching process S3 ends, the process moves to the first protective film removal process S4.

[0175] The steps after the first protective film removal step S4 are the same as in Embodiment 1, therefore, the description is omitted.

[0176] Thus, vibration element 1 is obtained.

[0177] As described above, according to this embodiment, in addition to the effects of Embodiment 1, the following effects can also be obtained.

[0178] In the first protective film 5, by setting T1=0, the etching of the interarm region Q4 can be performed in a shorter time.

[0179] 3. Implementation Method 3

[0180] Reference Figures 15-30 The manufacturing method of the vibration element 1 in Embodiment 3 is described below. Furthermore, structures identical to those in Embodiment 1 are labeled with the same reference numerals, and repeated descriptions are omitted.

[0181] In Embodiment 3, the first protective film 5b includes a first base film 51 and a third protective film 53, the first protective film forming process S2 includes a first base film forming process S100 and a third protective film forming process S110, the second protective film 6b includes a second base film 61 and a fourth protective film 63, and the second protective film forming process S5 includes a second base film forming process S120 and a fourth protective film forming process S130. In the first protective film 5b, T1 = 0 and T11 = 0. Otherwise, it is the same as in Embodiment 1.

[0182] 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.

[0183] <<First Protective Film Forming Process S2>>

[0184] like Figure 15 As shown, a first protective film 5b is formed on the first substrate surface 20A of the quartz substrate 20. The first protective film 5b includes a first base film 51 and a third protective film 53.

[0185] The first protective film 5b is formed in the first vibration arm forming region Q2 and the second vibration arm forming region Q3 on the first substrate surface 20A.

[0186] In detail, the first base film 51 in the first protective film 5b is formed in the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 on the first substrate surface 20A. The third protective film 53 in the first protective film 5b is formed in the first embankment forming region Qd1 on the side of the first base film 51 opposite to the quartz substrate 20. The side of the first base film 51 opposite to the quartz substrate 20 is the upper surface of the first base film 51.

[0187] That is, in the first groove forming region Q1 on the first substrate surface 20A, the first base film 51 is formed as the first protective film 5b. In the first embankment forming region Qd1 on the first substrate surface 20A, the first base film 51 and the third protective film 53 are formed as the first protective film 5b. In the first embankment forming region Qd1, the first base film 51 and the third protective film 53 are stacked in this order along the positive side of the Z direction.

[0188] The thickness T2 of the first protective film 5b in the first groove formation region Q1 of the first substrate surface 20A is the thickness of the first base film 51. The thickness T3 of the first protective film 5b in the first bank formation region Qd1 of the first substrate surface 20A is the total thickness of the thickness of the first base film 51 and the thickness of the third protective film 53. Since the first protective film 5b is not formed in the inter-arm region Q4 and the inter-element region Q5, the respective thicknesses T1 and T11 of the first protective film 5b in the inter-arm region Q4 and the inter-element region Q5 of the first substrate surface 20A are T1 = 0 and T11 = 0.

[0189] That is, the thickness of the first protective film 5b satisfies T1 < T2 < T3 and T11 < T2 < T3. In addition, in the present embodiment, T1 = 0 and T11 = 0, but as long as the thickness of the first protective film 5b satisfies T1 < T2 < T3 and T11 < T2 < T3, it may also be 0 < T1 and 0 < T11.

[0190] The first base film 51 will be described.

[0191] The first base film 51 is formed of a material that is etched at a predetermined etching rate in the first dry etching process S3.

[0192] In the present embodiment, the first base film 51 is a metal film formed of metal. The first base film 51 is formed by laminating the first metal film 512 and the second metal film 513. The first metal film 512 is formed on the first substrate surface 20A of the quartz substrate 20. The second metal film 513 is formed on the surface of the first metal film 512 opposite to the quartz substrate 20. The surface of the first metal film 512 opposite to the quartz substrate 20 is the upper surface of the first metal film 512. The first metal film 512 is formed of chromium (Cr). The second metal film 513 is formed of copper (Cu).

[0193] In addition, in the present embodiment, the first base film 51 is formed by laminating the first metal film 512 and the second metal film 513, but it is not limited thereto. It may also be formed of one film, or may be formed by laminating three or more films.

[0194] In addition, the first base film 51 may be formed of a material other than metal. For example, the first base film 51 may also be a resist film formed of a resist material. However, by making the first base film 51 a metal film, the thickness of the first base film 51 can be made thinner compared to the resist film. Thereby, the dimensional accuracy of the first vibrating arm 22, the second vibrating arm 23, the first grooves 221 and 231 formed in the first dry etching process S3, etc. can be improved.

[0195] Next, the third protective film 53 will be described.

[0196] The third protective film 53 is formed from the material that is etched at a specified etching rate in the first dry etching process S3.

[0197] In this embodiment, the third protective film 53 is a metal film formed of metal. For example, nickel (Ni) can be used as the metal forming the third protective film 53. Alternatively, the third protective film 53 can also be formed of a material other than metal. For example, the third protective film 53 can also be a resist film formed of a resist material. However, by making the third protective film 53 a metal film, its thickness can be reduced compared to a resist film. This further 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.

[0198] Next, the method for forming the first protective film 5b will be described.

[0199] like Figure 16 As shown, in this embodiment, the first protective film forming process S2 includes a first base film forming process S100 and a third protective film forming process S110.

[0200] The first base film formation process S100 is a process of forming the first base film 51 in the first substrate surface 20A of the quartz substrate 20, in the first vibrating arm forming region Q2 where the first vibrating arm 22 is formed and the second vibrating arm forming region Q3 where the second vibrating arm 23 is formed.

[0201] The first base film forming process S100 includes: a first base film coating process S101, which covers the first substrate surface 20A of the quartz substrate 20 with the first base film 51; and a first base film patterning process S102, which patterns the first base film 51.

[0202] In addition, the first basement membrane 51 is also referred to as basement membrane 51, and the first basement membrane formation process S100 is also referred to as basement membrane formation process S100.

[0203] The third protective film forming process S110 is the process of forming the third protective film 53 in the area of ​​the first base film 51 formed in the first base film forming process S100, excluding the first groove forming area Q1 that forms the first grooves 221 and 231, i.e., the first embankment forming area Qd1.

[0204] The third protective film forming process S110 includes: a third protective film coating process S111 in which the third protective film 53 covers the first base film 51; and a third protective film patterning process S112 in which the third protective film 53 is patterned.

[0205] In this embodiment, the process is performed in the order of the first base film coating process S101, the third protective film coating process S111, the third protective film patterning process S112, and the first base film patterning process S102. However, the order of each process S101, S102, S111, and S112 is not limited to this. For example, the process can be performed in the order of process S101, process S102, process S111, and process S112, or it can be performed in the order of process S101, process S111, process S102, and process S112.

[0206] <<First Base Film Coating Process S101>>

[0207] like Figure 17 As shown, the first substrate surface 20A of the quartz substrate 20 is covered by the first base film 51.

[0208] <<Third Protective Film Coating Process S111>>

[0209] like Figure 18 As shown, the first base film 51 is covered by a third protective film 53. The third protective film 53 is formed on the side of the first base film 51 opposite to the quartz substrate 20.

[0210] <<Third Protective Film Patterning Process S112>>

[0211] First, such as Figure 19 As shown, a second resist film R11 is formed on the side of the third protective film 53 opposite to the quartz substrate 20. The side of the third protective film 53 opposite to the quartz substrate 20 is the upper surface of the third protective film 53. The second resist film R11 is formed in the first embankment formation region Qd1 using photolithography. That is, the second resist film R11 overlaps with the first embankment formation region Qd1 when viewed from above.

[0212] Next, the third protective film 53 is etched from the side where the second resist film R11 is formed. That is, the third protective film 53 is etched from the upper surface side using the second resist film R11 as a mask. As a result, the third protective film 53 in the first trench forming region Q1, the inter-arm region Q4, and the inter-component region Q5 where the second resist film R11 is not formed is removed.

[0213] Thus, as Figure 20 As shown, a third protective film 53 can be formed in the first embankment forming region Qd1 on the upper surface of the first basement membrane 51.

[0214] Next, as Figure 21 As shown, the second resist film R11 is removed and the process is transferred to the first base film patterning step S102.

[0215] <<First Basement Membrane Mapping Process S102>>

[0216] First, such as Figure 22 As shown, a third resist film R12 is formed in the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3 in the first base film 51 using photolithography.

[0217] In this embodiment, before the first base film patterning step S102, a third protective film 53 is formed in the first embankment forming region Qd1. Therefore, in the first embankment forming region Qd1 of the first base film 51, the third resist film R12 is formed to cover the first base film 51 through the third protective film 53. In the first groove forming region Q1 of the first base film 51, the third resist film R12 is formed to cover the upper surface of the first base film 51 without being separated by the third protective film 53.

[0218] Next, the first base film 51 is etched from the side of the first base film 51 where the third resist film R12 is formed, with the third resist film R12 in between. That is, the first base film 51 is etched from the upper surface side of the first base film 51 using the third resist film R12 as a mask.

[0219] The third resist film R12 is formed in the first vibrating arm forming region Q2 and the second vibrating arm forming region Q3, but not in the inter-arm region Q4 and the inter-element region Q5. Therefore, in the first base film patterning process S102, the first base film 51 in the inter-arm region Q4 and the inter-element region Q5 is removed.

[0220] Thus, as Figure 23 As shown, a first base film 51 is formed in the first vibration arm forming region Q2 and the second vibration arm forming region Q3 on the first substrate surface 20A.

[0221] Next, the third resist film R12 is removed. This forms... Figure 15 The first protective film 5b is shown.

[0222] When the removal of the third resist film R12 is completed, the process moves to the first dry etching step S3.

[0223] <<First Dry Etching Process S3>>

[0224] This process is performed in the same way as in Implementation Method 1.

[0225] like Figure 24 As shown, the quartz substrate 20 is dry-etched from the first substrate surface 20A side through the first protective film 5b, thereby forming the shape of the first surface 2A, the first grooves 221 and 231 and the vibrating substrate 2.

[0226] In the first dry etching process S3, the first base film 51 and the third protective film 53 formed on the first substrate surface 20A of the quartz substrate 20 are etched at a predetermined etching rate. Therefore, the etching depth of the quartz substrate 20 in the region where the first substrate surface 20A is exposed without the first protective film 5b, the region where the first base film 51 is formed as the first protective film 5b, and the region where the first base film 51 and the third protective film 53 are formed as the first protective film 5b can be controlled by the first base film 51 and the third protective film 53.

[0227] That is, by forming a first protective film 5b containing a first base film 51 and a third protective film 53 in the first protective film forming process S2, the shapes of the first vibrating arm 22 and the second vibrating arm 23, as well as the first grooves 221 and 231, can also be formed in the first dry etching process S3 without utilizing the micro-load effect.

[0228] In addition, in the first protective film formation step S2, by forming the first protective film 5b which includes the first base film 51 and the third protective film 53, it is also possible to form the depths Aa and Ba of the shape of the vibrating substrate 2 to be deeper than the difference Ta-Wb between the thickness Ta of the quartz substrate 20 and the depth Wb of the second grooves 222 and 232 in the first dry etching step S3.

[0229] Furthermore, as described above, in this embodiment, during the first protective film formation step S2, the first protective film 5b is not formed in the inter-arm region Q4 and the inter-element region Q5 on the first substrate surface 20A. That is, in the first protective film 5b, T1 = 0 and T11 = 0. In other words, the first base film 51 is not formed in the inter-arm region Q4 and the inter-element region Q5 on the first substrate surface 20A.

[0230] Thus, since the first protective film 5b is not formed in the inter-arm region Q4 and the inter-component region Q5 on the first substrate surface 20A, the etching of the quartz substrate 20 in the inter-arm region Q4 and the inter-component region Q5 begins simultaneously with the start of the first dry etching process S3. Therefore, the first dry etching process S3 can be performed in a shorter time.

[0231] Furthermore, in this embodiment, the first dry etching process S3 is terminated when the first protective film 5b remains in the first embankment formation area Qd1 of the first substrate surface 20A. However, the first dry etching process S3 may also be terminated when the first protective film 5b does not remain in the first embankment formation area Qd1 of the first substrate surface 20A.

[0232] When the first dry etching process S3 ends, the process moves to the first protective film removal process S4.

[0233] The first protective film removal process S4 is the same as in Embodiment 1, so its description is omitted. The description will proceed from the second protective film formation process S5. After the first protective film removal process S4 is completed, the process moves to the second substrate surface 20B of the quartz substrate 20.

[0234] <<Second Protective Film Forming Process S5>>

[0235] like Figure 25 As shown, a second protective film 6b is formed on the second substrate surface 20B of the quartz substrate 20. The second protective film 6b includes a second base film 61 and a fourth protective film 63.

[0236] The second protective film 6b is formed in the second embankment region Qd2 on the second substrate surface 20B.

[0237] Specifically, the second base film 61 in the second protective film 6b is formed in the second embankment forming region Qd2 of the second substrate surface 20B. The fourth protective film 63 in the second protective film 6b is formed in the second embankment forming region Qd2 of the surface of the second base film 61 opposite to the quartz substrate 20. The surface of the second base film 61 opposite to the quartz substrate 20 is the lower surface of the second base film 61.

[0238] That is, a region Qd2 is formed in the second embankment of the second substrate surface 20B, and the second base film 61 and the fourth protective film 63 are formed as a second protective film 6b. The second base film 61 and the fourth protective film 63 are stacked in this order along the negative side of the Z direction in the region Qd2 formed in the second embankment.

[0239] The second basement membrane 61 will be described.

[0240] The second base film 61 is formed from a material that is etched at a specified etching rate in the second dry etching process S6.

[0241] In this embodiment, the second base film 61 is a metal film formed of metal. The second base film 61 is formed by stacking the first metal film 612 and the second metal film 613.

[0242] In addition, in this embodiment, the second base film 61 is formed by stacking the first metal film 612 and the second metal film 613, but it is not limited to this. It can also be formed by one film or by stacking three or more films.

[0243] Alternatively, the second base film 61 may also be formed of a material other than metal. For example, the second base film 61 may also be a resist film formed of a resist material.

[0244] Next, the fourth protective film 63 will be explained.

[0245] The fourth protective film 63 is formed from the material that is etched at a specified etching rate in the first dry etching process S3.

[0246] In this embodiment, the fourth protective film 63 is a metal film formed of metal. For example, nickel (Ni) can be used as the metal forming the fourth protective film 63. Alternatively, the fourth protective film 63 can also be formed of a material other than metal. For example, the fourth protective film 63 can also be a resist film formed of a resist material.

[0247] Next, the method for forming the second protective film 6b will be described.

[0248] like Figure 26 As shown, in this embodiment, the second protective film forming process S5 includes the second base film forming process S120 and the fourth protective film forming process S130.

[0249] The second base film formation process S120 is a process in which the second base film 61 is formed in the second embankment formation region Qd2 in the second substrate surface 20B of the quartz substrate 20.

[0250] The second base film formation process S120 includes a second base film coating process S121, which covers the second substrate surface 20B of the quartz substrate 20 with the second base film 61; and a second base film patterning process S122, which patterns the second base film 61.

[0251] The fourth protective film forming process S130 is the process of forming the fourth protective film 63 in the second embankment forming region Qd2 of the second base film 61 formed in the second base film forming process S120.

[0252] The fourth protective film forming process S130 includes: a fourth protective film coating process S131 in which the fourth protective film 63 covers the second base film 61; and a fourth protective film patterning process S132 in which the fourth protective film 63 is patterned.

[0253] In this embodiment, the process is performed in the order of the second base film coating process S121, the fourth protective film coating process S131, the fourth protective film patterning process S132, and the second base film patterning process S122. However, the order of each process S121, S122, S131, and S132 is not limited to this. For example, the process can also be performed in the order of process S121, process S122, process S131, and process S132.

[0254] <<Second base film coating process S121>>

[0255] like Figure 27 As shown, the second substrate surface 20B of the quartz substrate 20 is covered by the second base film 61.

[0256] <<4th Protective Film Coating Process S131>>

[0257] like Figure 27 As shown, the second base film 61 is covered by a fourth protective film 63. The fourth protective film 63 is formed on the side of the second base film 61 opposite to the quartz substrate 20.

[0258] <<4th Protective Film Patterning Process S132>>

[0259] First, such as Figure 27 As shown, a second resist film R11 is formed on the side of the fourth protective film 63 opposite to the quartz substrate 20. The side of the fourth protective film 63 opposite to the quartz substrate 20 is the lower surface of the fourth protective film 63. The second resist film R11 is formed in the second embankment formation region Qd2 using photolithography. That is, the second resist film R11 overlaps with the second embankment formation region Qd2 when viewed from above.

[0260] Next, the fourth protective film 63 is etched from the side where the second resist film R11 is formed. That is, using the second resist film R11 as a mask, the fourth protective film 63 is etched from its lower surface. Thus, as... Figure 28 As shown, the fourth protective film 63 in the second groove forming region Q6, the inter-arm region Q4, and the inter-element region Q5, where the second resist film R11 was not formed, was removed.

[0261] Next, as Figure 28 As shown, the second resist film R11 is removed and the process is transferred to the second base film patterning step S122.

[0262] <<Second Basement Membrane Patterning Process S122>>

[0263] First, such as Figure 29 As shown, the third resist film R12 is formed in the second embankment region Qd2 in the second base film 61 using photolithography.

[0264] In this embodiment, before the second base film patterning step S122, a fourth protective film 63 is formed in the second embankment forming region Qd2. Therefore, in the second embankment forming region Qd2 of the second base film 61, the third resist film R12 is formed to cover the second base film 61 through the fourth protective film 63.

[0265] Next, the second base film 61 is etched from the side of the second base film 61 where the third resist film R12 is formed, via the third resist film R12. That is, the second base film 61 is etched from the lower surface side of the second base film 61 using the third resist film R12 as a mask.

[0266] The third resist film R12 is formed in the second embankment forming region Qd2, but is not formed in the second trench forming region Q6, the inter-arm region Q4, and the inter-element region Q5. Therefore, in the second base film patterning process S122, the second base film 61 in the second trench forming region Q6, the inter-arm region Q4, and the inter-element region Q5 is removed.

[0267] Thus, a second base film 61 is formed in the second embankment region Qd2 on the second substrate surface 20B.

[0268] Next, the third resist film R12 is removed. This forms... Figure 25 The second protective film 6b is shown.

[0269] When the removal of the third resist film R12 is completed, the process moves to the second dry etching process S6.

[0270] <<Second Dry Etching Process S6>>

[0271] This process is performed in the same way as in Implementation Method 1.

[0272] like Figure 30 As shown, the quartz substrate 20 is dry-etched from the second substrate surface 20B side through the second protective film 6b, thereby forming the shape of the second surface 2B, the second grooves 222 and 232, and the vibrating substrate 2.

[0273] The second protective film 6b is not formed in the inter-arm region Q4, inter-element region Q5, and second trench formation region Q6 on the second substrate surface 20B. Therefore, in the second dry etching process S6, by performing dry etching, the depth Wb of the second trenches 222 and 232 is approximately equal to the depths Ab and Bb of the outer shape of the vibrating substrate 2.

[0274] Thus, by forming a second protective film 6b containing a second base film 61 and a fourth protective film 63 in the second protective film forming process S5, the shapes of the first vibrating arm 22 and the second vibrating arm 23, as well as the second grooves 222 and 232, can be formed simultaneously in the second dry etching process S6 without utilizing the micro-load effect.

[0275] Furthermore, in the first dry etching process S3, the shapes of the first vibrating arm 22 and the second vibrating arm 23 are formed so that the positions of the bottom surfaces 222A and 232A of the second grooves 222 and 232 formed in the Z direction are closer to the second substrate surface 20B. Therefore, in the second protective film forming process S5, even if the second protective film 6b is not formed in the second groove forming region Q6 of the second substrate surface 20B, the second dry etching process S6 can penetrate the inter-arm region Q4 and the inter-element region Q5 respectively.

[0276] Furthermore, the second protective film 6b is not formed in the second trench forming region Q6 on the second substrate surface 20B, so the second trenches 222 and 232 can be formed in a short time during the second dry etching process S6.

[0277] Furthermore, the second protective film 6b is not formed in the inter-arm region Q4 and inter-element region Q5 on the second substrate surface 20B. Therefore, in the second dry etching process S6, the inter-arm region Q4 and inter-element region Q5 can be penetrated in a short time.

[0278] In addition, in this embodiment, the second dry etching process S6 is ended when the second protective film 6b remains in the second embankment formation region Qd2 of the second substrate surface 20B. However, the second dry etching process S6 can also be ended when the second protective film 6b does not remain in the second embankment formation region Qd2 of the second substrate surface 20B.

[0279] When the second dry etching process S6 ends, the process moves to the second protective film removal process S7.

[0280] The steps after the second protective film removal step S7 are the same as in Embodiment 1, therefore, the description is omitted.

[0281] Thus, vibration element 1 is obtained.

[0282] Furthermore, in this embodiment, in the second base film formation process S120, the second base film 61 is formed in the second embankment formation region Qd2 of the second substrate surface 20B, and not in the second trench formation region Q6, the inter-arm region Q4, and the inter-element region Q5. However, the second base film 61 may also be formed in the second trench formation region Q6, the inter-arm region Q4, and the inter-element region Q5. That is, as... Figure 28 As shown, the second base film 61 can also be formed in the second embankment forming region Qd2, the second trench forming region Q6, the inter-arm region Q4, and the inter-element region Q5 on the second substrate surface 20B.

[0283] Even under these conditions, by performing dry etching in the second dry etching process S6, the depth Wb of the second trenches 222 and 232 is approximately equal to the depths Ab and Bb of the outer shape of the vibrating substrate 2. Therefore, the inter-arm region Q4 and the inter-element region Q5 are respectively connected, and the first vibrating arm 22 and the second vibrating arm 23 can be formed. Since it is not necessary to remove the second base film 61 from the second trench forming region Q6, the inter-arm region Q4, and the inter-element region Q5, the second base film patterning process S122 can be omitted, and the second protective film forming process S5 can be simplified.

[0284] As described above, the following effects can be obtained according to this embodiment.

[0285] By forming a first protective film 5b comprising a first base film 51 and a third protective film 53, the same effect as in Embodiment 1 can also be obtained.

[0286] Furthermore, by not forming the first basement membrane 51 in the interarm region Q4, i.e. by setting T1=0, the same effect as in Embodiment 2 can be obtained.

[0287] The manufacturing method of the vibration element 1 has been described above based on Embodiments 1, 2, and 3. 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.

[0288] Furthermore, there are no particular limitations on the vibration element manufactured by the manufacturing method of the vibration element of the present invention.

[0289] The vibration element manufactured by the method of manufacturing the vibration element of the present invention may be, for example, a vibrating element. Figure 31 and Figure 32 The double tuning fork type vibrating element 7 is shown. Additionally, in... Figure 31 and Figure 32 The 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.

[0290] Alternatively, for example, the vibrating element can also be Figure 33 , Figure 34 and Figure 35 The gyroscope oscillating element 8 is shown. Additionally, in... Figure 33 , Figure 34 as well as Figure 35 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 moved towards... Figure 33When the angular velocity ωz around 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.

[0291] 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.

[0292] Alternatively, for example, the vibrating element can also be Figure 36 , Figure 37 as well as Figure 38 The gyroscope oscillating element 9 is shown. Additionally, in... Figure 36 , Figure 37 as well as Figure 38 The electrodes are omitted from the diagram. The gyroscope vibration element 9 has a base 91, a pair of drive 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 drive vibration arms 92 and 93 are moved towards... Figure 36 When the angular velocity ωy around the Y-axis is applied under the bending vibration state in the direction of arrow SD, the detection vibration arms 94 and 95 are re-excited to bend in the direction of arrow SS 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.

[0293] 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, wherein, The vibrating element has 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 have a first surface and a second surface, a first groove with a bottom that opens on the first surface, a second groove with a bottom that opens on the second surface, and an outer surface that connects the first surface and the second surface in a third direction that intersects the first direction and the second direction, forming the outer shape of the first vibrating arm and the second vibrating arm. The first surface and the second surface are arranged in opposite directions in the third 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 on the surface of the first substrate; In the first dry etching process, the quartz substrate is dry etched from the first substrate side through the first protective film, and the first surface, the first groove, and a portion of the outer surface of the first vibrating arm and the second vibrating arm are formed simultaneously in the same process. The second protective film formation process involves forming a second protective film on the second substrate surface after the first dry etching process; and The second dry etching process involves dry etching the quartz substrate from the second substrate surface side through the second protective film, simultaneously forming the second surface, the second groove, and the remaining portions of the outer surfaces of the first and second vibrating arms in the same process. In the first dry etching process, a portion of the outer surface of the first vibrating arm and the second vibrating arm, in the third direction, ends at a position closer to the second substrate side than the position where the bottom surface of the second groove is formed in the third direction. The remaining portion of the outer surface of the first and second vibrating arms formed in the second dry etching process has a length in the third direction equal to the depth of the second groove formed in the second dry etching process. The outer surfaces of the first and second vibrating arms formed in the second dry etching process intersect with the outer surfaces of the first and second vibrating arms formed in the first dry etching process, thereby making the inter-arm region between the first vibrating arm forming region and the second vibrating arm forming region a continuous connection. When the thickness of the first protective film along the third direction in the inter-arm region is T1, the thickness of the first protective film along the third direction in the first groove forming region forming the first groove is T2, and the thickness of the first protective film along the third direction in the regions of the first and second vibrating arm forming regions other than the first groove forming region is T3, In the first protective film, T1 is satisfied. <T2<T3。 2. The method for manufacturing a vibrating element according to claim 1, wherein, In the first protective film, T1=0.

3. The method for manufacturing a vibrating element according to claim 1, wherein, The first protective film comprises a base film and a third protective film. The first protective film forming process includes: In the substrate film formation process, the substrate film is formed in the first substrate surface in the first vibrating arm forming region where the first vibrating arm is formed and the second vibrating arm forming region where the second vibrating arm is formed; and In the third protective film forming process, a third protective film is formed in the base film in a region other than the region where the first groove is formed.

4. The method for manufacturing a vibration element according to claim 3, wherein, The base film is not formed in the interarm region located between the first vibration arm forming region and the second vibration arm forming region on the first substrate surface.

5. A method for manufacturing a vibrating element according to any one of claims 1 to 4, wherein, The manufacturing method further includes a first protective film removal step, in which the residual first protective film is removed after the first dry etching step is completed while the first protective film remains on the surface of the first substrate.

6. The method for manufacturing a vibrating element according to claim 5, wherein, The manufacturing method further includes a second protective film removal step, in which the residual second protective film is removed after the second dry etching step is completed while the second protective film remains on the surface of the second substrate.

Images