Mounting structure for vibration body and inertial sensor

Abstract

To provide a mounting structure capable of suppressing contact between a vibration body and a plurality of electrode portions due to misalignment, and an inertial sensor using the same.SOLUTION: In a mounting structure in which a vibration body is mounted on a mounting substrate, the mounting substrate has a plurality of electrode portions 52 facing a rim 23 of the vibration body at a distance. An opposing surface 52b of the electrode portions 52 facing the rim 23 is inclined at least partially relative to the normal direction to the plane formed by the mounting substrate. The maximum diameter of the vibration body's rim 23 is defined as the vibration body maximum diameter. The electrode diameter is defined as the length of a straight line connecting two electrode portions, of the plurality of electrode portions 52, that face each other along the radial direction centered on the mounting center within the plane formed by the mounting substrate. In this case, the opposing surface 52b has a shape where a height position Z2 of the electrode minimum diameter at which the electrode diameter is minimized differs from a height position Z1 of the electrode maximum diameter. Furthermore, an inertial sensor has the mounting structure.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a mounting structure in which a vibrating body having a three-dimensional curved surface is mounted on a mounting substrate, and an inertial sensor using the same. [Background technology]

[0002] Conventionally, inertial sensors have been known that have a mounting structure in which a vibrating body with a three-dimensional curved surface is mounted on a mounting board with multiple electrodes (for example, Patent Document 1). The inertial sensor described in Patent Document 1 has a vibrating body with a three-dimensional curved surface in a roughly hemispherical shape that vibrates in wine-glass mode, and is a BRG formed on the mounting board, in which multiple independent electrodes are arranged at equal distances from the vibrating body while being spaced apart from it. BRG is an abbreviation for Bird-bath Resonator Gyroscope. This inertial sensor has a Q value that represents the state of vibration in the vibrating body of 10 6 This structure achieves the above level, so higher accuracy than conventional methods is expected. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2019 / 0094024 Summary of the Invention [Problem to be solved by the invention]

[0004] This type of inertial sensor drives the vibrating body and detects the applied physical quantity based on the electrostatic capacitance between the end of the hemispherical part of the vibrating body located on the opposite side from the part joined to the mounting substrate and the opposing electrode. Since the performance of this type of inertial sensor is ensured by making the distance between the vibrating body and the multiple opposing electrodes, i.e., the inter-electrode gap, narrow and uniform, high-precision position control is required when mounting the vibrating body on the multiple electrodes of the mounting substrate.

[0005] In order to increase the Q value of vibration, it is not preferable to attach alignment marks to vibrating bodies having a hemispherical shape. For vibrating bodies without alignment marks, for example, their outer shape is recognized by an imaging device such as a camera, and then they are assembled to a mounting substrate by flip-chip mounting based on the recognized outer shape information. However, this method has low alignment accuracy, which can cause contact between the vibrating body and the electrodes of the mounting substrate, resulting in short circuits and poor vibration of the vibrating body, which can lead to reduced yields.

[0006] The mounting structure described in Patent Document 1 is obtained by mounting a hemispherical vibrating body on a mounting substrate, providing a sacrificial layer between the vibrating body and multiple electrodes facing it to temporarily connect them, and etching and separating a portion of the sacrificial layer. This mounting structure can also be obtained by forming a spring structure for adjusting the position of the vibrating body on the mounting substrate in advance, and then using the spring structure to adjust the position so that the distances between the vibrating body and the multiple electrodes are approximately the same after mounting the vibrating body on the mounting substrate.

[0007] However, while the above manufacturing method prevents direct contact between the vibrating body and multiple electrodes after bonding the vibrating body to the mounting substrate, thereby preventing a decrease in yield, it requires a process of removing the sacrificial layer or spring structure, which takes time and increases manufacturing costs.

[0008] In view of the above, the present disclosure aims to provide a vibrating body mounting structure and an inertial sensor using the same that can prevent contact between a vibrating body mounted on a mounting board and multiple electrodes, even if misalignment occurs between the vibrating body and the mounting board, thereby preventing a decrease in yield. [Means for solving the problem]

[0009] According to one aspect of the present disclosure, a mounting structure for a vibrating body includes: A mounting structure in which a vibrating body (2) is mounted on a mounting substrate (3), The vibrator has a curved surface portion (21) having a three-dimensional curved surface, and a connecting portion (22) extending from the curved surface portion to the center of the inside of the curved surface portion, the mounting substrate is disposed at a position surrounding the area where the connection portion is joined, and has a plurality of electrode portions (52) that face, at a distance, a rim (23) at the end of the curved surface portion opposite to the connection portion; A point located directly below the center of the mounting surface (22b) of the connection portion of the mounting substrate is defined as a mounting center (C), a radial direction of the plane of the mounting substrate with the mounting center as its axis is defined as a substrate radial direction (D), the length of a straight line connecting two opposing electrode portions along the substrate radial direction is defined as an electrode diameter, and a position in the normal direction to the plane is defined as a height position, At least a portion of the opposing surface (52b) of each of the plurality of electrode portions that faces the rim is inclined relative to the normal direction, and the height position (Z2) of the electrode minimum diameter (R2) where the electrode diameter is smallest is different from the height position (Z1) of the vibrating body maximum diameter (R1) where the rim diameter is largest.

[0010] This mounting structure is formed by mounting a vibrating body having a three-dimensional curved surface portion and a connection portion on a mounting substrate having a plurality of electrode portions, and at least a portion of the surfaces of the plurality of electrodes that face the rim at the end of the curved surface portion of the vibrating body are inclined in a normal direction to the plane of the mounting substrate. Taking the position in the normal direction as a height position, in the mounting structure, the height position of the vibrating body maximum diameter, where the diameter of the rim of the vibrating body is maximum, differs from the height position of the electrode minimum diameter, where the diameter, which is the length of the straight line connecting two opposing electrode portions along the substrate radial direction D, is minimum. This ensures a gap between the rim of the vibrating body and the plurality of electrode portions of the mounting substrate after the vibrating body is mounted on the mounting substrate, and prevents contact between the rim and the electrodes even if the vibrating body is misaligned, resulting in a mounting structure that suppresses a decrease in yield.

[0011] The reference symbols in parentheses attached to each component indicate an example of the correspondence between the component and the specific components described in the embodiments described below. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view showing an inertial sensor according to a first embodiment. [Figure 2] FIG. 2 is a view taken along the arrow II in FIG. 1. [Figure 3] 10 is an explanatory diagram illustrating the relationship between the maximum diameter of the vibrating body and the minimum diameter between electrode portions of the mounting substrate. [Figure 4] FIG. 4 is a cross-sectional view showing a cross section along line IV-IV in FIG. [Figure 5] FIG. 5 is an enlarged cross-sectional view of region V in FIG. 4. [Figure 6] FIG. 10 is a cross-sectional view showing a part of a vibrating body and a counter electrode in a mounting structure of a comparative example. [Figure 7] 1A and 1B are explanatory diagrams illustrating mounting of a vibrating body on a mounting substrate according to an embodiment. [Figure 8A] 3A to 3C are cross-sectional views showing a first step in the manufacturing process of the inertial sensor of the first embodiment. [Figure 8B] FIG. 8B is a cross-sectional view showing a step subsequent to FIG. 8A. [Figure 8C] FIG. 8C is a cross-sectional view showing a step subsequent to FIG. 8B. [Figure 8D] FIG. 8D is a cross-sectional view showing a step subsequent to FIG. 8C. [Figure 8E] FIG. 8E is a cross-sectional view showing a step subsequent to FIG. 8D. [Figure 8F] FIG. 8C is a cross-sectional view showing a step subsequent to FIG. 8E. [Figure 8G] FIG. 8C is a cross-sectional view showing a step subsequent to FIG. 8F. [Figure 8H] FIG. 8C is a cross-sectional view showing a step subsequent to FIG. 8G. [Figure 8I] FIG. 8C is an explanatory diagram of alignment in FIG. 8H. [Figure 8J] FIG. 8C is a cross-sectional view showing a step subsequent to FIG. 8H. [Figure 9] FIG. 3 is a cross-sectional view showing a first modified example of the inertial sensor of the first embodiment. [Figure 10] FIG. 4 is a cross-sectional view showing a second modified example of the inertial sensor of the first embodiment. [Figure 11] FIG. 10 is a cross-sectional view showing a third modified example of the inertial sensor of the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In the following embodiments, identical or equivalent parts will be denoted by the same reference numerals.

[0014] (First embodiment) The inertial sensor 1 of the first embodiment will be described.

[0015] [Basic configuration] 1, the inertial sensor 1 has a mounting structure in which a vibrating body 2 that vibrates in wine-glass mode is mounted on a mounting substrate 3, and is suitable for application to various devices that utilize the vibration characteristics of the vibrating body 2, for example, gyro sensors such as BRGs. In this specification, a case in which the inertial sensor 1 is a BRG will be described as a representative example, but the application is not limited to this.

[0016] For ease of explanation, as shown in FIG. 1, a direction in the plane formed by the mounting substrate 3, which is a direction along one side of the outer casing, is referred to as the "x direction," a direction perpendicular to the x direction in the same plane is referred to as the "y direction," and a direction normal to the xy plane is referred to as the "z direction." The x, y, and z directions in FIG. 2 and subsequent figures correspond to the x, y, and z directions in FIG. 1, respectively. In addition, in this specification, "up" refers to the direction along the z direction in the figure and refers to the side indicated by the arrow, and "down" refers to the side opposite to the top. Furthermore, in this specification, the state in which the inertial sensor 1 or the mounting substrate 3 is viewed from above in the z direction is sometimes referred to as a "top view."

[0017] In FIG. 2, to make it easier to understand the configuration of the mounting board 3, the outer contour of the vibrating body 2 is shown by a two-dot chain line, and the outer contour of a frame portion 51 (described below) that is covered by the vibrating body 2 in top view is shown by a solid line.

[0018] 2 and 3, the vibrating body 2 is a micro-vibrating body with a three-dimensional, approximately symmetrical structure including a curved surface portion 21 including an outer shape of a three-dimensional curved surface having a substantially hemispherical shape, and a bottomed, cylindrical connecting portion 22 extending from the apex side of the imaginary hemisphere formed by the curved surface portion 21 toward the center of the inside of the hemisphere. In the vibrating body 2, for example, a recessed bottom surface 22a located inside the cylindrical portion of the bottomed, cylindrical connecting portion 22 serves as an adsorption surface used for holding and transporting by vacuum adsorption, and the surface opposite to the recessed bottom surface 22a serves as a mounting surface 22b to be bonded to the mounting substrate 3. For example, the side of the vibrating body 2 with a larger outer diameter is the front surface, and the opposite surface is the back surface, and conductive films (not shown) are formed on both the front surface and the back surface, allowing voltage application from the mounting substrate 3. In the vibrating body 2, for example, the rim 23, which is the end of the curved surface portion 21 opposite the connection portion 22, faces the multiple first electrode portions 52, and the rim 23 vibrates in a resonance mode due to the electrostatic force generated between the first electrode portions 52 and the rim 23. In the vibrating body 2, for example, the base having the curved surface portion 21 and the connection portion 22 is made of any reflow material such as glass or quartz, and the conductive film (not shown) is made of a laminated film of any conductive material such as chromium or gold.

[0019] The vibrating body 2 can be manufactured by preparing a plate made of a reflow material such as quartz and a mold (not shown) having a bowl-shaped recess and a support portion located at the center of the recess, setting the plate in the mold, and heating and softening it while reducing the pressure in the recess, thereby causing differential pressure deformation. The vibrating body 2 is formed, for example, by processing a thin substrate made of a reflow material using the above-mentioned forming process, resulting in a thin member on the order of micrometers, with the curved surface portion 21 and the connecting portion 22 having thicknesses of 10 μm to 100 μm. The vibrating body 2 has a millimeter-sized shape, for example, with the height direction being along the thickness direction of the mounting substrate 3, measuring 2.5 mm in height and 5 mm in outer diameter on the surface side of the rim 23.

[0020] 2 and 3, for convenience of explanation, a portion of the mounting board 3 located directly below the center of the connection portion 22 in a top view will be referred to as the "mounting center C," and a radial direction in the xy plane whose axis is the mounting center C will be referred to as the "board radial direction D." The mounting center C is, for example, a portion located at the center of an area surrounded by the frame portion 51 in a top view. In addition, a direction toward the mounting center C along the board radial direction D will be referred to as the "inner direction," and a direction away from the mounting center C will be referred to as the "outer direction."

[0021] 2 and 3, the maximum outer diameter of the vibrating body 2 is defined as the vibrating body maximum diameter R1, and the smallest outer diameter between the first electrode portions 52 of the mounting substrate 3 is defined as the electrode minimum diameter R2, where R1≦R2. The vibrating body maximum diameter R1 refers to the maximum value of the diameter of the rim 23 in the substrate radial direction D. Furthermore, the electrode minimum diameter R2 refers to the smallest value of the electrode diameter, where the electrode diameter is defined as the length of a straight line connecting, along the substrate radial direction D, two of the multiple first electrode portions 52 located at both ends in the substrate radial direction D.

[0022] 1 and 2, the mounting substrate 3 includes a lower substrate 4 and an upper substrate 5 which are joined together. The manufacturing process of the mounting substrate 3 will be described later.

[0023] The lower substrate 4 is a support for the upper substrate 5, and has a base made of, for example, borosilicate glass, which is an insulating material. The lower substrate 4 has, for example, grooves 41 and wiring 42 formed therein.

[0024] 1 to 3, the groove 41 is an annular groove provided between the frame portion 51 and the plurality of first electrode portions 52, and is formed by wet etching. The groove 41 has a dimension corresponding to the outer diameter of the rim 23 of the vibrating body 2, and is provided so that the rim 23 does not come into contact with the mounting substrate 3 when the vibrating body 2 is mounted on the mounting substrate 3. Note that if the vibrating body 2 has a shape in which the mounting surface 22b of the connection portion 22 protrudes beyond the rim 23, the lower substrate 4 may be configured without the groove 41.

[0025] The wiring 42 is made of any conductive material such as aluminum, and is arranged to pass between the plurality of first electrode portions 52, and is electrically independent from the plurality of first electrode portions 52. For example, a plurality of wirings 42 are provided, and one end of each wiring 42 is connected to the frame portion 51 and the other end to the second electrode portion 53 while spanning the groove 41 in the lower substrate 4, electrically connecting these together. Note that while FIG. 2 shows an example in which the lower substrate 4 has four wirings 42 as a representative example, the present invention is not limited to this, and the number and arrangement of the wirings 42 can be changed as appropriate.

[0026] The upper substrate 5 is made of, for example, silicon, a semiconductor material, and includes, for example, a frame portion 51, a plurality of first electrode portions 52, a second electrode portion 53, and an electrode film 54.

[0027] The frame body portion 51 is formed together with a plurality of first electrode portions 52 and second electrode portions 53, for example, by performing dry etching such as DRIE on the upper substrate 5. DRIE is an abbreviation for Deep Reactive Ion Etching. The frame body portion 51 has, for example, a circular ring shape when viewed from above, and is configured so that the connection portion 22 of the vibrating body 2 can be inserted into the enclosed area.

[0028] The multiple first electrode portions 52, for example, face the rim 23 of the vibrating body 2 and are arranged at equal intervals apart from one another so as to form a ring on the plane of the mounting substrate 3. An electrode film (not shown) is formed on the upper surface 52a of the multiple first electrode portions 52 opposite the lower substrate 4, and wires (not shown) are connected to the multiple first electrode portions 52, making it possible to control the potential of the multiple first electrode portions 52 by an external power source (not shown). Each of the multiple first electrode portions 52 is spaced a predetermined distance from the rim 23 of the vibrating body 2, and each forms a capacitor with the vibrating body 2, making it possible to detect the capacitance between the multiple first electrode portions 52 and the vibrating body 2. Some of the multiple first electrode portions 52 serve as detection electrodes that detect capacitance, and others serve as drive electrodes that apply an electrostatic force to the rim 23 of the vibrating body 2.

[0029] As shown in FIG. 5 , each of the first electrode portions 52 has a side surface adjacent to the upper surface 52a, and an opposing surface 52b facing the rim 23 has an inclined surface with an inverse tapered shape. The inverse tapered shape means that part or all of the opposing surface 52b has a surface shape that slopes outward as it moves from the top to the bottom in the z direction. Note that a surface shape in which part or all of the opposing surface 52b slopes inward as it moves from the top to the bottom in the z direction is referred to as a "forward tapered shape." In other words, the inverse tapered shape is a surface shape that moves away from the rim 23 or the mounting center C as it moves downward in the z direction, and the forward tapered shape is a surface shape that moves closer to the rim 23 or the mounting center C as it moves downward in the z direction.

[0030] 5, the opposing surfaces 52b of the plurality of first electrode portions 52 are all or partly inversely tapered, so that Z1 and Z2 are different height positions in the z direction, with Z1 being the height position where the vibrating body has a maximum diameter R1 and Z2 being the height position where the electrode has a minimum diameter R2. This ensures a gap between the rim 23 of the vibrating body 2 and the plurality of first electrode portions 52 after the vibrating body 2 is mounted on the mounting board 3, suppressing contact therebetween and resulting in a mounting structure that suppresses a decrease in yield.

[0031] Specifically, as shown in FIG. 6 , the mounting structure of the comparative example includes a frame portion 100 and a counter electrode 101 on the lower substrate 4, which face the rim 23 of the vibrating body 2. In the mounting structure of the comparative example, the frame portion 100 corresponds to the frame portion 51, and the counter electrode 101 corresponds to the first electrode portion 52, but the structures of the frame portion 100 and the counter electrode 101 are different from those of the frame portion 51 and the first electrode portion 52. The surfaces of the frame portion 100 and the counter electrode 101 facing the rim 23 are vertical surfaces along the thickness direction of the lower substrate 4. In the mounting structure of the comparative example, because the side surfaces of the counter electrode 101 are vertical surfaces as described above, the diameter connecting the two counter electrodes 101 arranged at both ends of the vibrating body 2 in the substrate radial direction D is constant in the z direction. Therefore, the mounting structure of the comparative example has a structure in which the height position Z1 at which the maximum diameter R1 of the vibrating body is reached when the vibrating body 2 is mounted is the same as the height position Z3 at which the electrode minimum diameter R2 is reached. In the mounting structure of the comparative example, when mounting the vibrating body 2 on the mounting substrate, if there is a misalignment between the vibrating body 2 and the mounting substrate, the rim 23 and the opposing electrode 101 may come into contact with each other during bonding or driving, making it difficult to prevent a decrease in yield.

[0032] On the other hand, in the mounting structure according to this embodiment, part or all of the facing surface 52b of the first electrode portion 52 has an inverse tapered shape, and height position Z1 and height position Z2 are different. As shown in Fig. 7, for example, this mounting structure is configured so that when the rim 23 of the vibrating body 2 and the first electrode portion 52 are aligned and the vibrating body 2 is mounted on the mounting substrate 3, a gap is secured between the rim 23 and the facing surface 52b. Therefore, in this mounting structure, even if misalignment occurs when mounting the vibrating body 2 on the mounting substrate 3, contact between the vibrating body 2 and the facing surface 52b after mounting on the mounting substrate 3 is suppressed, making it possible to suppress a decrease in yield due to misalignment.

[0033] 1, the second electrode unit 53 has a frame shape surrounding the plurality of first electrode units 52, and an electrode film (not shown) is formed on the upper surface opposite the lower substrate 4, and a wire (not shown) is connected to the electrode film (not shown). The second electrode unit 53 is connected to a conductive film (not shown) of the vibrating body 2 by wiring 42, allowing a voltage to be applied to the vibrating body 2. Note that the second electrode unit 53 is electrically independent from the first electrode unit 52 and may be electrically connected to the vibrating body 2, and is not limited to a frame shape, and the shape, arrangement, etc. may be changed as appropriate.

[0034] 4, the electrode film 54 is a conductive film formed in at least the region surrounded by the frame portion 51, and electrically connects the mounting substrate 3 and the vibrating body 2 with the bonding material 6. The electrode film 54 is made of a conductive material such as gold, and is formed by any film formation method such as vapor deposition. The electrode film 54 is formed, for example, on the region of the lower substrate 4 surrounded by the frame portion 51, on the sidewall of the frame portion 51 facing this, and on a part of the top surface connected to this, but the pattern shape and the formation location can be changed as appropriate.

[0035] The bonding material 6 is made of any conductive bonding material such as sintered silver, gold-tin, etc. The bonding material 6 may be made of any material that can be bonded to conductive films (not shown) formed on the front and back surfaces of the vibrating body 2, and the constituent material thereof may be changed as appropriate.

[0036] The above is the basic configuration of the inertial sensor 1 of this embodiment.

[0037] [Manufacturing method] Next, we will explain an example of a method for manufacturing the inertial sensor 1. Since the manufacturing of the vibrating body 2 has been described above, the following mainly explains the manufacturing of the mounting substrate 3 and the mounting of the vibrating body 2 thereon. In addition, in Figures 8D to 8G, the outline of the wiring 42 formed in another cross section is shown by a dashed line.

[0038] First, as shown in FIG. 8A, for example, an insulating borosilicate glass substrate is prepared as the lower substrate 4. Next, for example, a resist film (not shown) is formed in a pattern that exposes only the portion of the lower substrate 4 where the groove is to be formed. Subsequently, as shown in FIG. 8B, for example, a groove 41 is formed by etching, and then the resist film (not shown) is removed with a remover. Then, as shown in FIG. 8C, for example, a wiring 42 is formed in a pattern that spans the groove 41 by sputtering or the like using a mask (not shown).

[0039] Next, as shown in FIG. 8D, an upper substrate 5 made of conductive low-resistivity silicon or the like is prepared and anodically bonded to the surface of the lower substrate 4 on which the grooves 41 and wiring 42 are formed. Thereafter, as shown in FIG. 8E, trench etching is performed on the upper substrate 5 by DRIE or the like until the lower substrate 4 is partially exposed, forming a frame portion 51, a plurality of first electrode portions 52, and a second electrode portion 53. This etching step is performed, for example, by the Bosch process, and the process conditions for removing the portion of the upper substrate 5 between the frame portion 51 and the first electrode portions 52 may be adjusted so that the etching width in the xy plane direction increases toward the bottom in the z direction. As a result, the opposing surface 52b of the first electrode portion 52 has an inverse tapered shape.

[0040] The etching process for the upper substrate 5 may be performed, for example, by separately removing the portion of the upper substrate 5 between the frame portion 51 and the first electrode portion 52 and removing the other portion, with the conditions of the Bosch process being fixed for the latter process. Also, the minimum electrode diameter R2 of the multiple first electrode portions 52 and the arrangement of the mounting substrate 3 in the xy plane are designed as appropriate to match, for example, the outer diameter and shape of the rim 23 of the vibrating body 2 manufactured in a separate process.

[0041] Subsequently, for example, gold is vapor-deposited using a mask (not shown) having openings that expose predetermined regions including the region surrounded by the frame body portion 51, to form a patterned electrode film 54 as shown in Fig. 8F. Next, for example, the mounting substrate 3 on which the electrode film 54 has been formed is placed on a mounting device (not shown) having a heating mechanism, and a bonding material 6 made of sintered silver is placed in the region surrounded by the frame body portion 51 as shown in Fig. 8G.

[0042] Next, as shown in FIG. 8H, for example, the vibrating body 2 manufactured in a separate process is transported while being vacuum-sucked by a suction jig J, and is positioned relative to the mounting board 3 using an imaging device 10. For example, the vibrating body 2 held by the suction jig J is placed directly above the mounting board 3 by a transport device (not shown), and the imaging device 10 is inserted between them. Then, for example, images of the vibrating body 2 and the mounting board 3 are captured by the imaging device 10, and feature points are extracted using edge detection, a known image analysis technique, to obtain information on the outer shape of the rim 23, the vibrating body maximum diameter R1, and the outer shapes of the multiple first electrode portions 52, and the electrode minimum diameter R2. At this time, based on the obtained information, alignment is performed so that the gap G between the vibrating body maximum diameter R1 of the vibrating body 2 and the electrode minimum diameter R2 of the first electrode portion 52 is uniform, as shown in FIG. 8I, for example.

[0043] 8J, for example, the connection portion 22 of the vibrating body 2 held by the suction jig J is inserted into the area surrounded by the frame portion 51 of the mounting substrate 3, and the mounting surface 22b and the bonding material 6 are brought into contact. Then, the bonding material 6 is sintered and solidified using a heating mechanism (not shown), and the vacuum created by the suction jig J is released, and the suction jig J is lifted up from the vibrating body 2. Finally, for example, wires (not shown) are connected to the plurality of first electrode portions 52 and second electrode portions 53, making the vibrating body 2 connectable to an external circuit or the like.

[0044] Through the above steps, the inertial sensor 1 having the mounting structure of this embodiment can be manufactured. As described above, by forming an inverse tapered shape on the opposing surfaces 52b of the multiple first electrode portions 52, it is possible to obtain the inertial sensor 1 in which contact between the rim 23 and the first electrode portions 52 after the vibrating body 2 is mounted on the mounting substrate 3, and thus a decrease in yield, is suppressed.

[0045] According to this embodiment, the inertial sensor 1 includes a mounting structure in which a vibrating body 2 having a three-dimensional curved surface is mounted on a mounting substrate 3 having a plurality of first electrode portions 52, and at least a portion of the facing surface 52b of the first electrode portion 52 has an inverse tapered shape. Since the facing surface 52b of the first electrode portion 52 has an inverse tapered shape, the inertial sensor 1 is structured to ensure a gap between the rim 23 of the vibrating body 2 and the plurality of first electrode portions 52, even if misalignment occurs when mounting the vibrating body 2 on the mounting substrate 3. Therefore, the inertial sensor 1 suppresses contact between the rim 23 and the plurality of first electrode portions 52, which may be caused by misalignment when mounting the vibrating body 2 on the mounting substrate 3, and thus reduces yield, thereby achieving an effect of improving reliability.

[0046] (Variation 1) 9, the inertial sensor 1 may have a composite shape in which the facing surface 52b of the first electrode portion 52 has a reverse-tapered inclined surface and a vertical surface. For example, the first electrode portion 52 may have a predetermined region of the facing surface 52b including the upper end on the upper surface 52a side formed as a reverse-tapered inclined surface, and the remaining region including the lower end on the lower substrate 4 side formed as a vertical surface.

[0047] 9 shows an example in which the opposing surface 52b has a two-stage surface configuration consisting of one inclined surface and a vertical surface as a representative example, but is not limited to this. For example, the opposing surface 52b may have a multi-stage surface configuration consisting of two or more inclined surfaces in an inverted tapered shape and one vertical surface. In this way, the opposing surface 52b may have an n-stage surface configuration (n is an integer of 2 or more) consisting of one or more inclined surfaces in an inverted tapered shape from the upper end and a vertical surface on the lower end side.

[0048] This modification also provides the inertial sensor 1 with the same effects as those of the first embodiment. In this modification, the distance d between the rim 23 and the opposing surface 52b at the height position Z1 is smaller than when the entire opposing surface 52b has an inverse tapered shape, and this also provides the effect of further improving the sensor accuracy.

[0049] (Variation 2) 10, the inertial sensor 1 may have a composite shape in which the facing surface 52b of the first electrode portion 52 has a forward tapered inclined surface and a reverse tapered inclined surface. For example, the first electrode portion 52 has a predetermined region of the facing surface 52b including the upper end on the upper surface 52a side that is a forward tapered inclined surface, and the remaining region including the lower end on the lower substrate 4 side that is a reverse tapered inclined surface. In other words, the multiple first electrode portions 52 have a surface shape in which the height position Z2 at which the facing surface 52b has the electrode minimum diameter R2 is located midway between the upper end and the lower end.

[0050] This modification also provides the inertial sensor 1 with the same effects as those of the first embodiment. Furthermore, in this modification, as in the first modification, the distance d is smaller than when the entire opposing surface 52b has an inverse tapered shape, and therefore, an effect of further improving the sensor accuracy is also obtained.

[0051] (Variation 3) 11, the inertial sensor 1 may have a shape in which part or all of the opposing surface 52b of the first electrode portion 52 has a curved surface that curves outward as it goes downward in the z direction. The first electrode portion 52 may have a curved surface that corresponds to an inverse tapered shape over the entire area, or a predetermined region on the upper end side may have a curved surface that corresponds to an inverse tapered shape, and the remaining portion may be a vertical surface.

[0052] This modification also provides the inertial sensor 1 with the same effects as those of the first modification.

[0053] (summary) As described above, the inertial sensor 1 includes the vibrating body 2 and the mounting substrate 3, and has a mounting structure in which at least a portion of the facing surfaces 52b of the multiple first electrode units 52 is a flat surface, a curved surface, or a composite shape of these, inclined so as to move away from the rim 23 of the vibrating body 2. In this mounting structure, after the vibrating body 2 is mounted on the mounting substrate 3, the distance d between the rim 23 of the vibrating body 2 and the facing surfaces 52b of the multiple first electrode units 52 is ensured, compared to a comparative example in which the facing surfaces 52b are vertical. Therefore, the inertial sensor 1 has a structure in which contact between the rim 23 and the multiple first electrode units 52 caused by misalignment between the vibrating body 2 and the mounting substrate 3 is suppressed, and a decrease in yield is suppressed.

[0054] (Other embodiments) Although the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and modifications within the scope of equivalents. In addition, various combinations and forms, as well as other combinations and forms including only one element, more than one, or less than one, are also within the scope and spirit of the present disclosure.

[0055] It goes without saying that in each of the above embodiments, the elements constituting the embodiments are not necessarily essential unless they are specifically stated as essential or are clearly considered essential in principle. Furthermore, in each of the above embodiments, when numerical values ​​such as the number, values, amounts, and ranges of the components of the embodiments are mentioned, they are not limited to the specific numbers unless they are specifically stated as essential or are clearly limited to a specific number in principle. Furthermore, in each of the above embodiments, when the shapes, positional relationships, etc. of the components are mentioned, they are not limited to the shapes, positional relationships, etc., unless they are specifically stated or are clearly limited to a specific shape, positional relationship, etc. in principle. [Explanation of symbols]

[0056] 2...vibrating body, 21...curved surface portion, 22...connecting portion, 22b...mounting surface, 23...rim, 3...mounting board, 4...lower board, 5...upper board, 52...first electrode portion, 52b...opposing surface, C...mounting center, D...board radial direction, R1...maximum diameter of vibrating body, R2...minimum diameter of electrode, Z1...height position of maximum diameter of vibrating body, Z2...height position of minimum diameter of electrode

Claims

1. A mounting structure in which a vibrating body (2) is mounted on a mounting substrate (3), The vibrating body has a curved surface portion (21) having a three-dimensional curved surface, and a connecting portion (22) extending from the curved surface portion to the center of the inside of the curved surface portion, the mounting substrate has a plurality of electrode portions (52) that are arranged at positions surrounding the area where the connection portion is joined, and that face, at a distance, a rim (23) at the end of the curved surface portion opposite to the connection portion; A point located directly below the center of the mounting surface (22b) of the connection portion of the mounting substrate is defined as a mounting center (C), a radial direction of the plane formed by the mounting substrate with the mounting center as an axis is defined as a substrate radial direction (D), the length of a straight line connecting two of the electrode portions facing each other along the substrate radial direction is defined as an electrode diameter, and a position in a normal direction to the plane is defined as a height position, In the mounting structure, at least a portion of the opposing surface (52b) of the plurality of electrode portions that faces the rim is inclined with respect to the normal direction, and the height position (Z2) of the electrode minimum diameter (R2) where the electrode diameter is smallest is different from the height position (Z1) of the vibrating body maximum diameter (R1) where the diameter of the rim is large.

2. The mounting structure according to claim 1 , wherein at least a portion of the opposing surfaces of the plurality of electrode portions is inclined in a reverse tapered shape away from the rim.

3. The mounting substrate has a lower substrate (4) and an upper substrate (5), and the upper substrate is joined to the lower substrate; 3. The mounting structure according to claim 2, wherein the plurality of electrode portions are part of the upper substrate, and a predetermined region of the opposing surface is inclined in an inverse tapered shape away from the rim from an upper end of the opposing surface opposite the lower substrate.

4. The mounting substrate has a lower substrate (4) and an upper substrate (5), and the upper substrate is joined to the lower substrate; 3. The mounting structure according to claim 2, wherein the plurality of electrode portions are part of the upper substrate, and a predetermined region of the opposing surface from an upper end opposite the lower substrate is inclined in a forward tapered shape approaching the rim, and the remaining region is inclined in a reverse tapered shape away from the rim.

5. An inertial sensor comprising the mounting structure according to any one of claims 1 to 4.

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