Method for manufacturing curved support structure and hemispherical resonator gyroscope

Abstract

A manufacturing method of a curved support structure and a hemispherical resonator gyro are disclosed. The manufacturing method includes: a support portion forming step of forming a ring-shaped recess on an upper surface of a lower wafer by etching, etching a radial outer surface of a plane as a radial outer side of the recess, and forming a support portion having a higher apex than the radial outer surface on a substantially central portion of the recess; a first electrode forming step of forming a plurality of first electrodes arranged on the radial outer surface; a sacrificial layer depositing step of forming a ring-shaped deposition pattern as a sacrificial layer on the plurality of first electrodes; a second electrode forming step of forming a plurality of second electrodes arranged corresponding to the plurality of first electrodes on a bottom surface of an upper wafer; a bonding step of bonding the upper wafer and the lower wafer with the sacrificial layer while overlapping the plurality of first electrodes and the plurality of second electrodes; a radial outer portion separating step of separating a radial outer portion located on a radial outer side of the second electrode of the upper wafer by etching; a non-isobaric heating step of making a pressure in a mold cavity different from an ambient pressure, and vacuum heating the upper wafer, the lower wafer, and the sacrificial layer; and a sacrificial layer removing step of removing the sacrificial layer by etching.

Description

Technical Field

[0001] Embodiments of the present invention relate to a curved support structure that can be used as a hemispherical resonant gyroscope. Background Technology

[0002] Currently, the hemispherical resonator gyroscope is known as a gyroscope for detecting angular velocity. For example... Figure 19 , Figure 20 As shown, this type of hemispherical resonant gyroscope 9 includes a resonator 91 that is generally hemispherical in shape, a support portion 90 that supports the resonator 91, a plurality of electrodes 92 formed on the outside of the resonator 91 and arranged in a ring, and a plurality of electrodes 93 formed on the inside of the resonator 91 and arranged in a ring.

[0003] In the hemispherical resonant gyroscope 9, multiple electrodes 92 or multiple electrodes 93 are alternately used in the circumferential direction as either detection electrodes 92A, 93A or control electrodes 92B, 93B. By applying a suppression voltage to the control electrodes 92B, 93B, the resonator 91 resonates through electrostatic attraction. When an angular velocity is input in this state, the resonant shape of the resonator 91 rotates according to the angular velocity. By detecting the electrostatic capacitance between the resonator 91 and the detection electrodes 92A, 93A, the angular velocity can be obtained. Alternatively, multiple electrodes 94 formed below the resonator 91 and arranged in a ring (see...) can also be used. Figure 20 It is used as a detection electrode and a driving electrode.

[0004] In this type of hemispherical resonator gyroscope, its performance is determined by the Q value of the resonator and the positional relationship of the electrodes. To increase the Q value of the resonator to reduce noise and improve performance, quartz or synthetic glass with a low coefficient of thermal expansion is used as the resonator. In this case, although the resonator is formed by machining quartz or synthetic glass, both of these materials are difficult to machine and require high machining precision. Therefore, the formation of such a resonator requires final shape adjustment through laser processing after mechanical polishing and cutting, which makes the manufacturing cost very high.

[0005] Furthermore, to reduce the manufacturing cost of resonators, a manufacturing method using MEMS (Micro Electro Mechanical Systems) technology has been proposed. One known method involves heating a quartz wafer to a deformable temperature and then shaping it into a goblet or birdbath shape using suction or pressure.

[0006] However, this method requires laser cutting and polishing during the resonator separation process. Furthermore, adhesives are needed to bond the resonator to the substrate with electrodes. Therefore, the alignment accuracy of semiconductor devices used in conventional MEMS processes tends to deteriorate, potentially leading to performance degradation in the manufactured hemispherical resonator gyroscope. In addition, because this method is not a batch processing method, the manufacturing cost of the hemispherical resonator gyroscope is higher.

[0007] Existing technical documents

[0008] Patent document 1: Japanese Patent Application Publication No. 2016-148659 Patent Document 2: Specification of U.S. Patent No. 6,474,161 Patent Document 3: Specification of U.S. Patent No. 7,839,059 Patent document 4: Specification of U.S. Patent No. 10612925

[0009] Non-Patent Document 1: D. Senkal, CR Raum, AA Trusov, AM Shkel, “TITANIASILICATE / FUSED QUARTZ GLASSBLOWING FOR 3-D FABRICATION OF LOW INTERNAL LOSSWINEGLASS MICRO-STRUCTURES”, Solid-State, Actuators, and Microsystems Workshop, 2012, DOI: 10.31438 / trf.hh2012.72 Non-Patent Document 2: P. Pai, FK Chowdhury, CH Mastrangelo and M. Tabib-Azar, "MEMS-based hemispherical resonator gyroscopes", SENSORS, 2012 IEEE, Taipei, Taiwan, CHINA, 2012, pp. 1-4, doi: 10.1109 / ICSENS.2012.6411346. Non-Patent Document 3: D. Senkal, MJ Ahamed, MHA Ardakani, S. Askari and AMShkel, “Demonstration of 1 Million Q-Factor on Microglassblown WineglassResonators With Out-of-Plane Electrostatic Transduction”, in Journal ofMicroelectromechanical Systems, vol.24, no.1, pp. 29-37, Feb. 2015, doi:10.1109 / JMEMS.2014.2365113. Summary of the Invention

[0010] The problem to be solved by embodiments of the present invention is to provide a technique for manufacturing curved support structures that can be used as hemispherical resonator gyroscopes at a lower cost.

[0011] To address the aforementioned problems, the manufacturing method of the curved support structure involved in this embodiment includes an upper wafer and a lower wafer. The method comprises the following steps: a support portion forming step, wherein an annular recess is formed on the upper surface of the lower wafer by etching, a radially outer surface serving as the radially outer plane of the recess is etched, and a support portion having a apex higher than the radially outer surface is formed at approximately the center of the recess; a first electrode forming step, wherein a plurality of first electrodes arranged in a ring on the radially outer surface are formed; a sacrificial layer deposition step, wherein an annular deposition pattern is formed on the plurality of first electrodes as a sacrificial layer; and a second electrode forming step, wherein a second electrode is formed on the bottom surface of the upper wafer... The plurality of first electrodes are correspondingly arranged side-by-side in a ring-shaped arrangement of a plurality of second electrodes; a bonding step in which the upper wafer and the lower wafer are bonded together by overlapping the plurality of first electrodes and the plurality of second electrodes, sandwiching the sacrificial layer; a radially outer separation step in which, after the bonding step, the radially outer portion of the upper wafer located on the radially outer side of the second electrodes is separated by etching; a non-isobaric heating step in which, after the radially outer separation step, the pressure within the cavity defined by the upper wafer, the lower wafer, and the sacrificial layer is made different from the ambient pressure, and the upper wafer, the lower wafer, and the sacrificial layer are vacuum heated; and a sacrificial layer removal step in which, after the non-isobaric heating step, the sacrificial layer is removed by etching.

[0012] The hemispherical resonator gyroscope of the embodiment is manufactured from an upper wafer and a lower wafer through the following steps: a support forming step, in which an annular recess is formed on the upper surface of the lower wafer by etching, a radially outer surface serving as the radially outer plane of the recess is etched, and a support having a vertex higher than the radially outer surface is formed at approximately the center of the recess; a first electrode forming step, in which a plurality of first electrodes are formed disposed on the radially outer surface; a sacrificial layer deposition step, in which an annular deposition pattern is formed on the plurality of first electrodes as a sacrificial layer; and a second electrode forming step, in which a plurality of second electrodes are formed on the bottom surface of the upper wafer, corresponding to the plurality of first electrodes. The bonding step involves bonding the upper wafer and the lower wafer together with the sacrificial layer in a manner that overlaps the plurality of first electrodes and the plurality of second electrodes; the radially outer separation step involves separating the radially outer portion of the upper wafer located radially outside the second electrodes by etching after the bonding step; the non-isobaric heating step involves making the pressure within the cavity defined by the upper wafer, the lower wafer, and the sacrificial layer different from the ambient pressure after the radially outer separation step, and vacuum heating the upper wafer, the lower wafer, and the sacrificial layer; and the sacrificial layer removal step involves removing the sacrificial layer by etching after the non-isobaric heating step.

[0013] According to embodiments of the present invention, a curved support structure that can be used as a hemispherical resonant gyroscope can be manufactured at a lower cost. Attached Figure Description

[0014] Figure 1 This is a flowchart illustrating a method for manufacturing the curved surface support structure involved in the embodiment.

[0015] Figure 2 This is a top view showing the structure of the lower wafer with recesses.

[0016] Figure 3 yes Figure 2 AA-line cross-section diagram.

[0017] Figure 4 This is a top view showing the structure of the lower wafer with electrodes formed.

[0018] Figure 5 yes Figure 4 BB line cross-section diagram.

[0019] Figure 6 This is a top view showing the structure of the lower wafer with the sacrificial layer formed.

[0020] Figure 7 yes Figure 6 CC line cross-section diagram.

[0021] Figure 8It is a bottom view showing the structure of the upper wafer on which electrodes are formed.

[0022] Figure 9 yes Figure 8 DD line cross-section diagram.

[0023] Figure 10 This is a top view showing the upper and lower wafers after bonding.

[0024] Figure 11 yes Figure 10 EE line cross-section diagram.

[0025] Figure 12 It is a side cross-sectional view showing the upper wafer that is separated radially outward.

[0026] Figure 13 It is a side cross-sectional view of the upper and lower wafers being vacuum heated under conditions where the pressure in the pressurized chamber is lower than that in the sealed space.

[0027] Figure 14 It is a side cross-sectional view of a curved support structure with an annular convex surface.

[0028] Figure 15 It is a three-dimensional cross-sectional view of a curved support structure with an annular convex surface.

[0029] Figure 16 It is a side cross-sectional view of the upper and lower wafers being vacuum-heated under conditions where the pressure in the pressurized chamber is higher than that in the sealed space.

[0030] Figure 17 It is a side cross-sectional view of a curved support structure with an annular concave surface.

[0031] Figure 18 It is a three-dimensional cross-sectional view of a structure with a concave annular surface supporting a curved structure.

[0032] Figure 19 This is a schematic top view showing the structure of an existing hemispherical resonant gyroscope.

[0033] Figure 20 This is a side cross-sectional view showing the structure of an existing hemispherical resonant gyroscope.

[0034] Reference Symbol List 1. Lower wafer 2. Wafer 3. Depositional Patterns 4A and 4B curved surface support structures 10 concavity 11 Support section 12 Radial outer surface 13 First Electrode 23 Second electrode 21A Annular convex surface 21B Annular concave surface 22 Flange portion Detailed Implementation

[0035] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0036] (Manufacturing method of curved surface support structure) The manufacturing method of the curved surface support structure involved in the embodiments will be briefly described. Figure 1 This is a flowchart illustrating the manufacturing method of the curved surface support structure involved in this embodiment. Further details regarding each step will be described later.

[0037] like Figure 1 As shown, firstly, a support portion formation step (S101) is performed on the lower wafer to form a support portion by etching a support surface, a first electrode formation step (S102) is performed to form a first electrode, and a sacrificial layer deposition step (S103) is performed to perform sacrificial layer deposition patterning. Furthermore, a second electrode formation step (S104) is performed on the upper wafer to form a second electrode.

[0038] After performing the sacrificial layer deposition step and the second electrode formation step, a bonding step (S105) is performed to bond the upper wafer and the lower wafer together through the sacrificial layer, and a radial outer separation step (S106) is performed to separate the radial outer part of the upper wafer.

[0039] After the radial external separation step, an isobaric heating step (S107) and a non-isobaric heating step (S108) are performed by vacuum heating through a vacuum heating device with a pressurization chamber, and a sacrificial layer removal step (S109) is performed to remove the sacrificial layer, thereby producing a curved support structure that can be used as a hemispherical resonant gyroscope.

[0040] (Steps for forming the support section) The steps for forming the support section are explained. Figure 2 This is a top view showing the structure of the lower wafer with recesses. Figure 3 yes Figure 2 AA-line cross-section diagram.

[0041] like Figure 2 , Figure 3As shown, the support portion forming step involves forming the support portion 11 by forming an annular recess 10 on the lower wafer 1. The lower wafer 1 is a plate-shaped component made of a silicon compound such as synthetic quartz, silicon, TEMPAX glass, or low-expansion glass. In the support portion forming step, while the recess 10 is formed on its upper surface by isotropic etching, a radially outer surface 12 is formed on the radially outer side of the recess 10 by etching. This radially outer surface 12 is a plane with a height lower than the apex of the support portion 11. Furthermore, the distance of the height difference between the apex of the support portion 11 and the radially outer surface 12 will be described in detail later.

[0042] (First electrode formation step) The steps for forming the first electrode are explained. Figure 4 This is a top view showing the structure of the lower wafer with electrodes formed. Figure 5 yes Figure 4 BB line cross-section diagram.

[0043] like Figure 4 , Figure 5 As shown, the first electrode forming step involves forming a plurality of first electrodes 13 made of a high-melting-point metal on the radially outer surface 12 of the lower wafer 1. The plurality of first electrodes 13 are formed on the radially outer surface 12 in a ring-like arrangement arranged side by side around the recess 10. Furthermore, each of the plurality of first electrodes 13 has a connecting line 131 extending radially outward.

[0044] (Sacrificial layer deposition steps) The steps for sacrificial layer deposition are explained. Figure 6 This is a top view showing the structure of the lower wafer with the sacrificial layer formed. Figure 7 yes Figure 6 CC line cross-section diagram.

[0045] like Figure 6 , Figure 7 As shown, the sacrificial layer deposition step is a step of forming an annular deposition pattern 3 covering multiple first electrodes 13 using liquid glass such as TEOS (Tetraethyl Orthosilicate Tetraethoxysilane) and polysilazane. Furthermore, this deposition pattern is maintained in a semi-solid state until the bonding step described later.

[0046] (Second electrode formation step) The steps for forming the second electrode are explained. Figure 8 It is a bottom view showing the structure of the upper wafer on which electrodes are formed. Figure 9 yes Figure 8 DD line cross-section diagram.

[0047] like Figure 8 , Figure 9 As shown, the second electrode formation step involves forming a plurality of second electrodes 23 on the upper wafer 2. The upper wafer 2 is a plate-shaped component made of a silicon compound such as synthetic quartz, silicon, Tempax glass, or low-expansion glass, similar to the lower wafer 1. In the second electrode formation step, a plurality of second electrodes 23, corresponding to each of the plurality of first electrodes 13, are formed on the bottom surface of the upper wafer 2. Here, the plurality of second electrodes 23 are formed in a ring-like arrangement arranged side-by-side, just like the plurality of first electrodes 13.

[0048] Furthermore, in this embodiment, each of the plurality of second electrodes 23 is formed to a smaller size so that it can be housed within the area of ​​the corresponding first electrode 13 when overlapping with it. However, the first electrode 13 may also be formed to a smaller size than the second electrode 23. Thus, by forming one of the first electrode 13 or the second electrode 23 in a way that allows it to be housed within the area of ​​the other, the effects of misalignment that may occur during the bonding step can be reduced.

[0049] Furthermore, in the support formation step, the radial outer surface 12 is etched such that the distance between the apex of the support 11 and the radial outer surface 12 is greater than the distance formed by combining the thicknesses of the first electrode 13 and the second electrode 23. Accordingly, a gap is formed between the first electrode 13 and the second electrode 23 that are overlapped by the bonding step described later.

[0050] (Adhesion Steps) The bonding steps are explained below. Figure 10 This is a top view showing the upper and lower wafers after bonding. Figure 11 yes Figure 10 EE line cross-section diagram.

[0051] like Figure 10 , 11 As shown, the bonding step involves bonding the bottom surface of the upper wafer 2 to the upper surface of the lower wafer 1, thereby overlapping the plurality of first electrodes 13 and the plurality of second electrodes 23 corresponding to these electrodes. In this bonding step, with the upper wafer 2 and the lower wafer aligned using a double-sided alignment device, they are fixed by pressure, and then calcined at 300 to 500°C using a vacuum heating device under a predetermined cavity pressure P1, thereby bonding the upper wafer 2 and the lower wafer 1. At this time, the cavity pressure P1 is the pressure within the annular cavity C defined by the recess 10 on the lower wafer 1, the support portion 11, the bottom surface of the upper wafer 2, and the deposition pattern 3.

[0052] Alternatively, when the upper wafer 2 and lower wafer 1 are made of Tempax glass or silicon, an anodizing device can be used to bond the upper wafer 2 and lower wafer 1 instead of a double-sided alignment device. Regardless of the method used, this bonding step can control the alignment error to the semiconductor process level (below 5µm).

[0053] (Radial external separation step) The radial external separation procedure is explained. Figure 12 This is a side cross-sectional view showing the upper wafer separated radially outwards. Additionally, Figure 12 It shows the relationship with Figure 3 , Figure 5 , Figure 7 and Figure 11 The corresponding cross section is shown based on the planes extending in the vertical and horizontal directions and passing through the support in the figure.

[0054] like Figure 12 As shown, the outer diameter separation step is a step of separating the radial outer portion of the upper wafer 2 by etching. Here, the radial outer portion refers to the portion of the upper wafer 2 located radially outside the deposition pattern 3, with the center of the support portion 11 as the center of the circle.

[0055] According to the non-isobaric heating step, although the upper wafer 2 is deformed into a three-dimensional shape as detailed below, the flat upper wafer 2 is etched before the non-isobaric heating step, so that precise patterns of semiconductor processes can be applied, and at the same time, it is possible to avoid the need for costly laser cutting and polishing steps.

[0056] Furthermore, although etching may create sharp-angled portions at the ends of the upper wafer 2, heating via isobaric and non-isobaric heating steps rounds off the ends of the upper wafer 2. Accordingly, when the curved support structure manufactured using this method is used as a hemispherical resonator gyroscope, the Q value is improved due to enhanced energy confinement.

[0057] (Isobaric heating step and non-isobaric heating step) The isobaric heating step and the non-isobaric heating step are explained. Figure 13 , Figure 16 These are side cross-sectional views showing the upper and lower wafers being vacuum-heated under different conditions: one with lower pressure in the pressurized chamber than in the sealed space, and the other with higher pressure in the pressurized chamber than in the sealed space. Additionally, Figure 13 , Figure 16 It means based on and Figure 12 A diagram of a cross-section on the same plane.

[0058] The isobaric heating step involves making the ambient pressure P2 in the pressurization chamber of the vacuum device approximately the same as the mold cavity pressure P1, and then vacuum heating the upper wafer 2 and lower wafer 1 until they soften. In the isobaric heating step, when the materials of the upper wafer 2 and lower wafer 1 are quartz, the temperature in the pressurization chamber is 1200–1400°C; when the materials are Tempax glass, the temperature in the pressurization chamber is 500–600°C. According to the isobaric heating step, the support portion 11 of the lower wafer 1 and the upper wafer 2 are fused together. Furthermore, the deposition pattern 3, made of liquid glass, is fused with the lower wafer 1 and the upper wafer 2, thereby increasing the airtightness of the mold cavity C. Additionally, since the fusion of the lower wafer 1 and the upper wafer 2, and the fusion of the deposition pattern 3 with the lower wafer 1 and the upper wafer 2, also occur through a non-isobaric heating step, the isobaric heating step can be omitted from this manufacturing method.

[0059] The non-isobaric heating step involves making the ambient pressure P2 different from the mold cavity pressure P1, i.e., making the ambient pressure P2 lower than the mold cavity pressure P1 or making the ambient pressure P2 higher than the mold cavity pressure P1, and then vacuum heating the upper wafer 2 and the lower wafer 1 until they soften. In the non-isobaric heating step, when the materials of the upper wafer 2 and the lower wafer 1 are quartz, the temperature in the pressurization chamber is 1400℃~1700℃; when the materials are Tempax glass, the temperature in the pressurization chamber is 600℃~700℃.

[0060] In the non-isobaric heating step, when the ambient pressure P2 is lower than the mold cavity pressure P1, such as Figure 13 As shown, the expansion of the mold cavity C deforms a portion of the upper wafer 2, forming an annular convex surface 21A that protrudes upward in a ring shape. Furthermore, the portion of the upper wafer 2 that is fused with the annular deposition pattern 3 does not deform, but forms a flange portion 22 that protrudes radially outward from the end of the annular convex surface 21A.

[0061] On the other hand, in the non-isobaric heating step, when the ambient pressure P2 is higher than the mold cavity pressure P1, such as Figure 16 As shown, the upper wafer 2 is deformed by the shrinkage of the mold cavity C, forming an annular concave surface 21B that protrudes downward in a ring shape. In addition, similar to the case of forming an annular convex surface 21A, the portion of the upper wafer 2 that is fused with the annular deposition pattern 3 does not deform, but forms a flange portion 22 that protrudes radially outward from the end of the annular concave surface 21B.

[0062] In either the non-isobaric heating step where the ambient pressure P2 is lower than the mold cavity pressure P1, or the non-isobaric heating step where the ambient pressure P2 is higher than the mold cavity pressure P1, the thickness, height, curvature, etc. of the annular convex surface 21A and the annular concave surface 21B can be adjusted to the desired thickness, height, curvature, etc., by adjusting the pressure difference between the mold cavity pressure P1 and the ambient pressure P2, the temperature inside the vacuum chamber during vacuum heating, the lifting time of the lifting mechanism in the vacuum heating device, etc.

[0063] In addition, during the non-isobaric heating step, the liquid glass that forms the deposition pattern 3 has a composition close to quartz, which improves the airtightness of the mold cavity C, but its chemical resistance is poor compared to the materials of the upper wafer 2 and the lower wafer 1.

[0064] (Sacrificial layer removal steps) The steps for removing the sacrificial layer are explained below. Figure 14 , Figure 15 These are, respectively, a side section view and a three-dimensional section view showing the structure of a curved support structure with an annular convex surface. Figure 17 , Figure 18 These are, respectively, a side section view and a three-dimensional section view showing the structure of a curved support structure with an annular concave surface. Additionally, Figure 14 , Figure 15 , Figure 17 and Figure 18 All are based on and Figure 12 , Figure 13 A diagram of a cross-section on the same plane.

[0065] The sacrificial layer removal step is a step of removing the deposited pattern 3 formed by liquid glass through etching. The deposited pattern 3, which is deformed by vacuum heating, is etched faster than other parts, thus allowing for selective removal by etching. Furthermore, in the sacrificial layer removal step, chemicals that etch only the liquid glass forming the deposited pattern 3 can be used.

[0066] Based on the sacrificial layer removal step, manufacture as follows: Figure 14 and Figure 15 The curved support structure 4A shown has an upwardly projecting annular convex surface 21A, or as... Figure 17 , Figure 18 The curved support structure 4B shown has a downwardly projecting annular concave surface 21B. The curved support structure 4A includes an annular convex surface 21A, a flange 22, a support portion 11 supporting the annular convex surface 21A at approximately the center, a first electrode 13, and a second electrode 23. Furthermore, the curved support structure 4B differs from the curved support structure 4A only in that it has an annular concave surface 21B instead of an annular convex surface 21A.

[0067] According to the manufacturing method described above, the curved support structures 4A and 4B, which can be used as hemispherical resonator gyroscopes, can be manufactured using existing low-cost processes. Furthermore, according to this manufacturing method, the annular convex surface 21A, the annular concave surface 21B, the support portion 11, the first electrode 13, and the second electrode 23, all having a three-dimensional structure, are uniformly formed. Therefore, mechanical alignment is not required during the manufacturing process. Moreover, when the curved support structures 4A and 4B are used as hemispherical resonator gyroscopes, performance degradation caused by misalignment such as drift can be prevented.

[0068] In addition, although in this embodiment, a plurality of first electrodes 13 and a plurality of second electrodes 23 are described as being arranged in a ring, the plurality of first electrodes 13 may be disposed on the radial outer surface 12. Furthermore, the plurality of second electrodes 23 may be disposed on the bottom surface of the upper wafer 2 in correspondence with the plurality of first electrodes 13.

[0069] The embodiments of the present invention are presented by way of example only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, with various omissions, substitutions, and modifications possible without departing from the spirit of the invention. These embodiments or variations thereof are included within the scope and spirit of the invention, and are encompassed by the invention as described in the claims and its equivalents.

Claims

1. A method for manufacturing a curved support structure, comprising an upper wafer and a lower wafer, characterized in that, include: The support portion forming step involves etching an annular recess on the upper surface of the lower wafer, etching the radial outer surface of the plane that is the radial outer side of the recess, and forming a support portion with a apex higher than the radial outer surface at the center of the recess. The first electrode forming step involves forming a plurality of first electrodes disposed on the radial outer surface; In the sacrificial layer deposition step, a ring-shaped deposition pattern is formed on the plurality of first electrodes as a sacrificial layer; In the second electrode formation step, a plurality of second electrodes are formed on the bottom surface of the upper wafer, which are arranged corresponding to the plurality of first electrodes. In the bonding step, the upper wafer and the lower wafer are sandwiched together and bonded by overlapping the plurality of first electrodes and the plurality of second electrodes; A radial outer separation step, following the bonding step, involves etching to separate the radial outer portion of the upper wafer located radially outside the second electrode. In the non-isobaric heating step, after the radial external separation step, the pressure within the mold cavity defined by the upper wafer, the lower wafer, and the sacrificial layer is made different from the ambient pressure, and the upper wafer, the lower wafer, and the sacrificial layer are vacuum heated. The sacrificial layer removal step involves removing the sacrificial layer by etching after the non-isobaric heating step. as well as The isobaric heating step, after the radial external separation step and before the non-isobaric heating step, equalizes the pressure inside the mold cavity with the ambient pressure and vacuum heats the upper wafer, the lower wafer, and the sacrificial layer.

2. The method for manufacturing a curved surface support structure according to claim 1, characterized in that, The upper wafer and the lower wafer are made of silicon compound. The deposition pattern is formed from liquid glass.

3. The method for manufacturing a curved surface support structure according to claim 1 or 2, characterized in that, In the non-isobaric heating step, the ambient pressure is lower than the pressure inside the mold cavity, and vacuum heating is performed.

4. The method for manufacturing a curved surface support structure according to claim 1 or 2, characterized in that, In the non-isobaric heating step, the ambient pressure is made higher than the pressure inside the mold cavity and vacuum heating is performed.

5. The method for manufacturing a curved surface support structure according to claim 1 or 2, characterized in that, The plurality of first electrodes are arranged in a ring in parallel on the radial outer surface. The plurality of second electrodes are arranged in a ring on the bottom surface of the upper wafer, corresponding to the plurality of first electrodes.

6. The method for manufacturing a curved surface support structure according to claim 3, characterized in that, The plurality of first electrodes are arranged in a ring in parallel on the radial outer surface. The plurality of second electrodes are arranged in a ring on the bottom surface of the upper wafer, corresponding to the plurality of first electrodes.

7. The method for manufacturing a curved surface support structure according to claim 4, characterized in that, The plurality of first electrodes are arranged in a ring in parallel on the radial outer surface. The plurality of second electrodes are arranged in a ring on the bottom surface of the upper wafer, corresponding to the plurality of first electrodes.

8. A hemispherical resonant gyroscope, manufactured from an upper wafer and a lower wafer through the following steps: The support portion forming step involves etching an annular recess on the upper surface of the lower wafer, etching the radial outer surface of the plane that is the radial outer side of the recess, and forming a support portion with a apex higher than the radial outer surface at the center of the recess. The first electrode forming step involves forming a plurality of first electrodes disposed on the radial outer surface; In the sacrificial layer deposition step, a ring-shaped deposition pattern is formed on the plurality of first electrodes as a sacrificial layer; In the second electrode formation step, a plurality of second electrodes are formed on the bottom surface of the upper wafer, which are arranged corresponding to the plurality of first electrodes. In the bonding step, the upper wafer and the lower wafer are sandwiched together and bonded by overlapping the plurality of first electrodes and the plurality of second electrodes; A radial outer separation step, following the bonding step, involves etching to separate the radial outer portion of the upper wafer located radially outside the second electrode. In the non-isobaric heating step, after the radial external separation step, the pressure within the mold cavity defined by the upper wafer, the lower wafer, and the sacrificial layer is made different from the ambient pressure, and the upper wafer, the lower wafer, and the sacrificial layer are vacuum heated. The sacrificial layer removal step involves removing the sacrificial layer by etching after the non-isobaric heating step. as well as The isobaric heating step, after the radial external separation step and before the non-isobaric heating step, equalizes the pressure inside the mold cavity with the ambient pressure and vacuum heats the upper wafer, the lower wafer, and the sacrificial layer.

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