Mounting structure of micro vibrator

Abstract

To provide a packaging structure in which a minute vibration body having a surface electrode is joined to a mounting substrate, and to allow detection of a voltage applied to the surface electrode without a contact with a portion of the surface electrode other than the joint part with the mounting substrate.SOLUTION: A mounting substrate 3 has a plurality of divided inner frame parts 51 that are arranged separate from each other, and wiring for voltage application 42A and wiring for voltage detection 42B that are connected with different divided inner frame parts, and is connected with a connection part 22 of a minute vibration body 2. The wiring for voltage detection 42B is arranged at a distance from the wiring for voltage application 42A on the mounting substrate 3, and is electrically independent of the wiring for voltage application 42A. The wiring 42A and the wiring 42B are connected with different divided inner frame parts 51, and one end of the mounting substrate 3 facing the divided inner frame part 51 is an electrode connection part 421 connected with a surface electrode 23.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a mounting structure for a micro-vibrator having a three-dimensional curved surface. [Background technology]

[0002] In recent years, the development of autonomous driving systems for vehicles has progressed, and this type of system requires highly accurate self-location estimation technology. For example, for so-called Level 3 autonomous driving, development of a self-location estimation system equipped with a GNSS (Global Navigation Satellite System) and an IMU (Inertial Measurement Unit) is underway. The IMU is, for example, a six-axis inertial force sensor consisting of a three-axis gyro sensor and a three-axis acceleration sensor. In order to realize so-called Level 4 or higher autonomous driving in the future, an IMU with even higher sensitivity than the current system will be required.

[0003] The BRG (Bird-bath Resonator Gyroscope) is considered to be a promising gyro sensor for realizing such a highly sensitive IMU, and is made up of a micro-vibrator with a roughly hemispherical three-dimensional curved surface that vibrates in wine glass mode, mounted on a mounting board. This micro-vibrator has a Q value, which represents the state of vibration, of 10 6 This is expected to result in higher sensitivity than before.

[0004] An example of this type of mounting structure between a micro-vibrator and a mounting substrate is described in Patent Document 1. In this mounting structure, a cylindrical joint with a bottom extending from near the apex of a three-dimensional curved surface of a substantially hemispherical shape of the micro-vibrator toward the inner center of the hemisphere is inserted into a joint area of ​​the mounting substrate surrounded by a substantially annular frame. In this mounting structure, a surface electrode covering the entire surface of the micro-vibrator is joined to wiring formed in the joint area of ​​the mounting substrate, and a predetermined voltage can be applied to the surface electrode of the micro-vibrator via the wiring of the mounting substrate. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US Patent Application Publication No. 2019 / 0094024 Summary of the Invention [Problem to be solved by the invention]

[0006] Now, this BRG is configured to apply a voltage to the surface electrode of the micro-vibrator bonded to the bonding area electrically connected to the wiring formed on the mounting board, and in order to ensure the stability of the voltage application, the bonding reliability between the micro-vibrator and the mounting board is important. Also, in this mounting structure, in order to check whether a voltage is being applied to the surface electrode of the micro-vibrator, it is necessary to detect the voltage by probing the part of the surface electrode other than the bonding part with the mounting board.

[0007] However, if the probe is directly brought into contact with the surface electrode of the micro-vibrator, there is a risk of scratching the surface electrode or the base material covered by the surface electrode. Furthermore, if the surface electrode or base material is scratched, the Q value of the micro-vibrator decreases. Furthermore, for example, if a cover material is attached to the mounting board and the micro-vibrator is sealed, the probe cannot be brought into contact with the surface electrode of the micro-vibrator, and the applied voltage of the surface electrode cannot be detected.

[0008] In view of the above, an object of the present invention is to provide a mounting structure in which a micro-vibrator having a three-dimensional curved shape and a surface electrode covering the surface is bonded to a mounting substrate, which makes it possible to detect the applied voltage of the surface electrode without contacting any part of the surface electrode other than the bonded part with the mounting substrate. [Means for solving the problem]

[0009] In order to achieve the above object, the mounting structure of the micro-vibrator described in claim 1 comprises a micro-vibrator (2) having a curved portion (21) having a three-dimensional curved surface of a hemispherical shape, a connection portion (22) extending from the curved portion toward the center of the hemispherical shape, and a surface electrode (23) covering at least a portion of the connection portion and the curved portion, and a mounting board (3) having two or more wirings (42) and to which a portion of the micro-vibrator is connected, one end of the wiring located on the inner frame region side is an electrode connection portion (421) connected to a portion of the surface electrode that covers the connection portion, and the two or more wirings include at least one voltage application wiring (42A) for applying a voltage to the surface electrode and one voltage detection wiring (42B) for detecting the voltage applied to the surface electrode, and the voltage detection wiring is arranged at a distance from the voltage application wiring on the mounting board.

[0010] In the mounting structure of this micro-vibrator, a portion of the surface electrode of the micro-vibrator that covers the connection portion is joined to an electrode connection portion that is one end of a voltage detection wiring formed on a mounting board. This voltage detection wiring is disposed at a distance from the voltage application wiring to the surface electrode of the micro-vibrator among the wirings formed on the mounting board, and is electrically independent from the voltage application wiring on the mounting board. Therefore, this mounting structure can detect the voltage of the surface electrode through the voltage detection wiring without directly touching the surface electrode of the micro-vibrator other than the connection portion with the mounting board. Therefore, this mounting structure can prevent damage to the surface electrode of the micro-vibrator and the base material covered by it and a decrease in the Q value, and can check the reliability of the connection between the micro-vibrator and the mounting board by electrical characteristics such as the electrical resistance of a path having a voltage application wiring and a voltage detection wiring at both ends.

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

[0012] [Figure 1] FIG. 2 is a top view layout diagram showing the mounting structure of the first embodiment. [Diagram 2] 1 is a perspective cross-sectional view showing a micro-vibrator according to a first embodiment. [Diagram 3] 3 is a cross-sectional view showing a cross-sectional configuration taken along line III-III in FIG. 2. [Figure 4A] 10A to 10C are cross-sectional views showing a member preparation step in the process of forming a micro-vibrator having a three-dimensional curved surface. [Figure 4B] FIG. 4B is a cross-sectional view showing a step of forming the micro-vibrator subsequent to FIG. 4A. [Figure 4C] FIG. 4C is a cross-sectional view showing a step of forming the micro-vibrator subsequent to FIG. 4B. [Diagram 5] FIG. 2 is a top view layout diagram showing a mounting board according to the first embodiment. [Figure 6] 6 is a cross-sectional view showing a cross-sectional configuration taken along line VI-VI in FIG. 5. [Figure 7] 7 is a cross-sectional view showing a cross-sectional configuration taken along line VII-VII in FIG. 5. [Figure 8] FIG. 2 is a cross-sectional view showing a cross-sectional configuration taken along line VIII-VIII in FIG. [Figure 9] FIG. 2 is a cross-sectional view showing a cross-sectional configuration taken along line IX-IX in FIG. [Figure 10] FIG. 13 is an enlarged top view layout diagram of a predetermined region including an opposing region of the mounting board, showing another example of a divided inner frame portion and an electrode connection portion. [Figure 11] FIG. 11 corresponds to FIG. 10 and is a top view layout diagram showing another example of the divided inner frame portion and the electrode connection portion. [Figure 12] FIG. 11 corresponds to FIG. 10 and is a top view layout diagram showing another example of the divided inner frame portion and the electrode connection portion. [Figure 13] FIG. 2 is an explanatory diagram for explaining electrical connection between a surface electrode and a bridge wiring in the mounting structure of the first embodiment. [Figure 14] FIG. 11 corresponds to FIG. 10 and is a top surface layout diagram showing a modified example of the mounting board in the first embodiment. [Figure 15] 15 is a diagram showing a state in which the micro-vibrator is bonded to the mounting substrate in FIG. 14, and is a cross-sectional view showing a cross section corresponding to the cross section taken along line XV-XV in FIG. 14. [Figure 16] 13 is a perspective view showing a joint portion between a micro-vibrator and a mounting substrate in a mounting structure according to a second embodiment. FIG. [Figure 17] FIG. 11 is a perspective view showing a connection portion of a micro-vibrator in a second embodiment. [Figure 18] 18 is a perspective view showing a cap mask used when forming a surface electrode having the pattern shape in FIG. 17. FIG. [Figure 19] FIG. 11 is a perspective view showing a connection portion of a micro-vibrator in a modified example of the second embodiment. [Figure 20] FIG. 11 corresponds to FIG. 10 and is a top view layout diagram showing a configuration of a part of a mounting board in a modified example of the second embodiment. [Figure 21] 21 is a diagram showing a joint portion between a micro-vibrator and a mounting substrate in a mounting structure according to a modified example of the second embodiment, and is a cross-sectional view showing a cross section taken along line XXI-XXI in FIG. 20. FIG. [Figure 22] FIG. 22 is a cross-sectional view showing a mounting structure according to another modified example of the second embodiment, corresponding to FIG. 21. [Diagram 23] 13 is a cross-sectional view showing a joint portion between a micro-vibrator and a mounting substrate in a mounting structure according to a third embodiment. FIG. [Figure 24] FIG. 11 corresponds to FIG. 10 and is a top surface layout diagram showing the configuration of a mounting board in a modified example of the mounting structure of the third embodiment. [Diagram 25] FIG. 11 is a cross-sectional view showing an example of a mounting structure according to another embodiment. [Figure 26] FIG. 11 is a top view layout diagram showing another configuration example of a mounting board according to another embodiment. [Figure 27] FIG. 15 is a diagram corresponding to FIG. 14, showing an example of a connection structure between a surface electrode of a micro-vibrator and wiring of a mounting board according to another embodiment. [Figure 28] FIG. 15 is a diagram corresponding to FIG. 14, showing another example of a connection structure between a surface electrode of a micro-vibrator and a wiring of a mounting board according to another embodiment. [Figure 29] FIG. 15 is a diagram corresponding to FIG. 14, showing another example of a connection structure between a surface electrode of a micro-vibrator and a wiring of a mounting board according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be denoted by the same reference numerals.

[0014] (First embodiment) The mounting structure 1 of the first embodiment will be described with reference to the drawings. The mounting structure 1 of the present embodiment has a micro-vibrator 2 that vibrates in a wine glass mode, and is suitable for application to various devices that utilize the vibration characteristics of the micro-vibrator 2, such as gyro sensors such as BRGs and clock devices. In this specification, the mounting structure 1 is applied to a BRG as a representative example, but the mounting structure 1 is not limited to this application, and can, of course, be applied to other applications such as inertial sensors different from gyro sensors.

[0015] In Fig. 2, in order to make it easier to understand the configuration of the micro-vibrator 2 described later, a part of the micro-vibrator 2 is omitted to show the cross section, and the part of the outer periphery of the micro-vibrator 2 that cannot be seen from the angle shown in Fig. 2 is shown by a dashed line. In Figs. 10 to 12, in order to make it easier to understand other configuration examples of the bridge wiring 42 and the divided inner frame portion 51 of the mounting substrate 3 described later, a predetermined region including the divided inner frame portion 51 is shown, and other components of the mounting substrate 3 are omitted. In Figs. 10 to 12, the bridge wiring 42 is hatched, although it is not shown in cross section.

[0016] For the sake of convenience, the direction along the left-right direction on the paper as shown in FIG. 1 is referred to as the "x direction", the direction perpendicular to the x direction on the paper as the "y direction", and the normal direction to the xy plane as the "z direction". The x, y, and z directions in FIG. 3 and subsequent figures correspond to the x, y, and z directions in FIG. 1, respectively. In addition, in this specification, "upper" refers to the direction along the z direction in the figure, and means the side indicated by the arrow, and "lower" refers to the opposite side to the upper side. Furthermore, in this specification, the state in which the mounting structure 1 or the mounting board 3 is viewed from above in the z direction, as shown in FIG. 1, may be referred to as "top view".

[0017] 1, the mounting structure 1 of the present embodiment includes a micro-vibrator 2 and a mounting substrate 3, and a part of the micro-vibrator 2 is joined to the mounting substrate 3. The mounting structure 1 is configured to detect an angular velocity applied to the mounting structure 1 based on a change in electrostatic capacitance between the thin-walled micro-vibrator 2 capable of vibrating in a wine glass mode and a plurality of electrode parts 53 (described later) of the mounting substrate 3.

[0018] As shown in Fig. 2, the micro-vibration body 2 has a curved surface portion 21 including an external shape of a three-dimensional curved surface of a hemisphere, and a connecting portion 22 extending from the apex side of the imaginary hemisphere formed by the curved surface portion 21 toward the center side of the hemisphere. The connecting portion 22 is, for example, a cylindrical recess with a bottom. For example, the curved surface portion 21 of the micro-vibration body 2 has a three-dimensional curved surface in a bowl shape, and the Q value of the vibration is 10 5 That's all.

[0019] An end of the curved surface portion 21 opposite to the connection portion 22 is the rim 211, and the rim 211 is, for example, substantially cylindrical. When the micro-vibrator 2 is mounted on the mounting substrate 3, the rim 211 is mounted such that the front surface 2a side faces a plurality of electrode portions 53 of the mounting substrate 3, which will be described later, and the plurality of electrode portions 53 are equally spaced apart. When mounted on the mounting substrate 3, the micro-vibrator 2 is a portion that is in a hollow state, with the curved surface portion 21 including the rim 211 not in contact with other members. The micro-vibrator 2 is structured such that the hollow rim 211 can vibrate in a wine glass mode when mounted on the mounting substrate 3.

[0020] 2 and 3, the micro-vibrator 2 has a surface electrode 23 covering part or all of both surfaces, with the surface having a larger outer diameter as the front surface 2a and the opposite surface as the back surface 2b. The surface of the connection portion 22 of the micro-vibrator 2 facing the back surface 2b serves as the mounting surface 22b facing the mounting board 3. In this embodiment, for example, the surface of the bottom surface of the connection portion 22 opposite the mounting surface 22b serves as the adsorption surface 22a used for adsorbing and transporting the micro-vibrator 2.

[0021] The surface electrode 23 is, for example, but not limited to, a laminated film of Cr (chromium) or Ti (titanium) and an arbitrary conductive material such as Au (gold) or Pt (platinum) from the base side, or a single layer film of a conductive material having adhesion to the base material such as TiN (titanium nitride). The surface electrode 23 is formed on the front surface 2a and the back surface 2b of the micro-vibrator 2 by an arbitrary film forming method such as sputtering, vapor deposition, or ALD (atomic layer deposition). In this embodiment, the surface electrode 23 is formed on at least the mounting surface 22b and the front surface 2a of the rim 211, and these parts are electrically connected. The surface electrode 23 may be a solid shape that covers the entire front and back surfaces of the micro-vibrator 2, or may be a pattern shape that is patterned to have the above-mentioned configuration and covers a part of the front and back surfaces. In the micro-vibrator 2, a part of the surface electrode 23 that covers the mounting surface 22b of the connection portion 22 is connected to an electrode connection portion 421 (described later) of the mounting board 3 via a bonding member 52.

[0022] The micro-vibrator 2 is made of a material such as, for example, quartz, glass containing additives such as borosilicate glass, metallic glass, silicon, ceramic, etc. The material of the micro-vibrator 2 is not limited to the above-mentioned material, as long as it can form the curved surface portion 21 and the connection portion 22 having a three-dimensional curved shape and can vibrate in wine glass mode. The micro-vibrator 2 is formed, for example, by processing a thin-walled base material made of the above-mentioned material in a forming process described later, so that the curved surface portion 21 and the connection portion 22 are thin members on the order of micrometers, with the thickness of the curved surface portion 21 and the connection portion 22 being 10 μm to 100 μm. The micro-vibrator 2 has a millimeter-sized shape, for example, with the height direction being along the thickness direction of the mounting substrate 3, and the outer diameter of the surface 2a side of the rim 211 being 5 mm.

[0023] The micro-vibrator 2 is formed, for example, by the following process.

[0024] First, as shown in FIG. 4A, for example, a quartz plate 20, a mold M for forming a three-dimensional curved shape, and a cooling body C for cooling the mold M are prepared. The mold M includes, for example, a recess M1 that serves as a space when forming a three-dimensional curved shape on the quartz plate 20, and a support part M2 that extends along the depth direction of the recess M1 at the center of the recess M1 and supports a part of the quartz plate 20 during processing. The mold M has a through hole M11 for decompression formed on the bottom surface of the recess M1. The cooling body C includes an insertion part C1 into which the mold M is inserted, and an exhaust port C11 for exhaust on the bottom surface of the insertion part C1, and plays a role of cooling the mold M when processing the quartz plate 20. The quartz plate 20 is arranged so as to cover the entire area of ​​the recess M1 of the mold M.

[0025] Next, as shown in FIG. 4B, for example, a flame F is blown from a torch T toward the quartz plate 20 to melt the quartz plate 20. At this time, the recess M1 of the mold M is evacuated through an exhaust port C11 of the cooling body C by a vacuum mechanism (not shown). As a result, the molten part of the quartz plate 20 is stretched toward the bottom surface of the recess M1, and the central peripheral area is supported by the support part M2. After that, the heating of the quartz plate 20 is stopped and the quartz plate 20 is cooled, so that the quartz plate 20 has a curved surface part 201 having a substantially hemispherical three-dimensional curved shape, and a recessed part 202 having a recessed shape near the center of the curved surface part 201 by being supported by the support part M2. In addition, the part of the quartz plate 20 located outside the recess M1 is located at the outer periphery of the curved surface part 201, and becomes an end part 203 having a flat shape.

[0026] Next, the depression M1 of the mold M is returned to normal pressure, the processed quartz plate 20 is removed, and the quartz plate 20 is sealed with a sealant E made of any curable resin material, as shown in Fig. 4C, for example. Thereafter, for example, polishing and CMP (short for Chemical Mechanical Polishing) are performed on the sealant E from the surface on the end 203 side to the portion shown by the dashed line in Fig. 4C, and the end 203 is removed together with the sealant E. As a result, the quartz plate 20 has a shape having a curved surface portion 21 having an annular curved surface and a connection portion 22 recessed from the apex of the curved surface portion 21.

[0027] Then, the sealing material E is entirely removed by any method such as heating or dissolving with a chemical solution, and the quartz plate 20 is taken out. Finally, surface electrodes 23 are formed on both the front and back surfaces of the quartz plate 20 after the above processing, for example, by a film formation process such as sputtering or vapor deposition. The surface electrodes 23 may be patterned by a known method such as using a mask (not shown) as necessary.

[0028] The micro-vibrator 2 is manufactured by, for example, the manufacturing process as described above, but is not limited to this manufacturing method example. For example, the heat source for melting the quartz plate 20 shown in Fig. 4B may be a heater capable of heating the quartz plate 20 in the same area as when the flame F is used, instead of the flame F from the torch T. In this way, the manufacturing process of the micro-vibrator 2 may be appropriately changed, and other known methods may be adopted.

[0029] The micro-vibration body 2 has a substantially half-toroidal shape that is rotationally symmetric with respect to the Z direction as the axis of rotation, but is not limited to the illustrated BR shape as long as the curved surface portion 21 has a three-dimensional curved bowl shape and is capable of vibrating in wine glass mode. For example, the connection portion 22 may be a cylindrical recess with a bottom, or may be a columnar shape.

[0030] The mounting substrate 3 includes a lower substrate 4 and an upper substrate 5, which are bonded together, as shown in FIG. 5, for example. The mounting substrate 3 is obtained by anodically bonding the upper substrate 5, which is made of a semiconductor material, Si (silicon), to the lower substrate 4, which is made of borosilicate glass, which is an insulating material. The mounting substrate 3 includes, for example, a plurality of divided inner frame portions 51 on the side of the upper substrate 5, a plurality of electrode portions 53 arranged at a distance from each other so as to surround the divided inner frame portions 51, and a divided outer frame portion 54 arranged at a distance from each other so as to surround the electrode portions 53, on the side of the upper substrate 5. The mounting substrate 3 also includes, for example, an annular groove 41 surrounding the plurality of divided inner frame portions 51 while separating the plurality of divided inner frame portions 51 from the plurality of electrode portions 53, and a plurality of bridge wirings 42 spanning the inside and outside of the groove 41, on the side of the lower substrate 4.

[0031] The grooves 41 are grooves provided between the multiple divided inner frame portions 51 and the multiple electrode portions 53, as shown in Figures 6 and 7, for example, and are formed by wet etching or the like. The grooves 41 have a dimension corresponding to the outer diameter of the rim 211 of the micro-vibrator 2, as shown in Figures 8 and 9, for example, and are provided to prevent the rim 211 from contacting the mounting substrate 3 when the micro-vibrator 2 is mounted on the mounting substrate 3.

[0032] The bridge wirings 42 are made of a conductive material such as Al (aluminum), are arranged to pass between the electrode portions 53, and are electrically independent of the electrode portions 53. As shown in FIG. 7, the bridge wirings 42 straddle the grooves 41 in the lower substrate 4, and have one end connected to the divided inner frame portion 51 and the other end connected to the divided outer frame portion 54, electrically connecting them. For example, at least two bridge wirings 42 are formed and connected to different divided inner frame portions 51. The bridge wirings 42 have an inner frame region defined as a region surrounded by the divided inner frame portion 51 of the mounting substrate 3, and one end of the bridge wirings 42 on the inner frame region side serves as an electrode connection portion 421 that is connected to the surface electrode 23 of the micro-vibrator 2.

[0033] The bridge wirings 42 include at least one of a voltage application wiring 42A for applying a voltage to the surface electrode 23 of the micro-vibrator 2 and a voltage detection wiring 42B for detecting the voltage of the surface electrode 23. The voltage detection wiring 42B is disposed at a distance from the voltage application wiring 42A on the mounting board 3, and is electrically independent of the voltage application wiring 42A before the micro-vibrator 2 is connected. In other words, the electrode connection portion 421 of the voltage detection wiring 42B is electrically independent of at least the electrode connection portion 421 of the voltage application wiring 42A. For example, the other end of the bridge wiring 42 opposite to the electrode connection portion 421 is connected to the divided outer frame portion 54 or a terminal (not shown) that can be taken out to the outside, so that a voltage can be applied to the surface electrode 23 and a voltage can be detected even after the micro-vibrator 2 is sealed with a lid (not shown).

[0034] 5 shows an example in which a total of four bridge wirings 42, including three voltage application wirings 42A and one voltage detection wiring 42B, are formed on the mounting board 3, and each bridge wiring 42 is electrically independent, but the present invention is not limited to this example. The bridge wiring 42 only needs to have one or more voltage application wirings 42A and voltage detection wirings 42B that are electrically independent from each other, and the number, arrangement, etc. of the voltage application wirings 42A may be changed as appropriate. In addition, when a plurality of voltage application wirings 42A are formed, each may be electrically independent from the other voltage application wirings 42A, or may be electrically connected to each other. The same applies to the voltage detection wiring 42B.

[0035] The divided inner frame parts 51 are, for example, in a discontinuous annular shape as a whole when viewed from above, and are arranged apart from each other. At least two divided inner frame parts 51 are arranged, and as shown in Figs. 8 and 9, for example, their outer and inner sides are sized so as not to abut against the micro-vibration body 2. For example, at least one of the divided inner frame parts 51 is connected to the voltage application wiring 42A, and at least another is connected to the voltage detection wiring 42B. Some of the divided inner frame parts 51 may not be connected to the bridge wiring 42.

[0036] The divided inner frame parts 51 may be formed in four parts as shown in FIG. 5, and may have a shape obtained by equally dividing a circular frame body into four parts, but are not limited to this, and the number, arrangement, shape, dimensions, etc. may be appropriately changed. For example, the divided inner frame parts 51 may be formed in a shape obtained by dividing a circular frame body into two parts as shown in FIG. 10, and the voltage application wiring 42A may be connected to one of the parts, and the voltage detection wiring 42B may be connected to the remaining one. The divided inner frame parts 51 may be formed in a shape obtained by dividing a circular frame body into three parts as shown in FIG. 11, and the voltage application wiring 42A may be connected to one of the parts, the voltage detection wiring 42B may be connected to the remaining one, and the bridge wiring 42 may not be connected to the remaining one. The multiple divided inner frame portions 51 may be formed in three, for example as shown in Figure 12, and may be configured to be spaced apart from each other and surround an opposing region R1, with the region of the mounting substrate 3 facing the connection portion 22 of the micro-vibration body 2 being the opposing region R1.

[0037] 10 to 12, the electrode connection parts 421 of the multiple bridge wirings 42 may be configured to be spaced apart from each other and have parts disposed within the opposing region R1. That is, the electrode connection parts 421 may have a shape that follows the inner contour of the divided inner frame part 51 in a top view, or may have other shapes such as a circular shape or an elliptical shape, and the shape, arrangement, dimensions, and the like may be appropriately changed depending on the divided inner frame part 51 and the connection parts 22 of the micro-vibration body 2.

[0038] The multiple electrode portions 53 are disposed at a distance from one another so as to surround the divided inner frame portion 51 at positions on the outer periphery side of the groove 41. For example, as shown in Fig. 5, the multiple electrode portions 53 have inner and outer periphery sides each having an arc shape in top view, and when the inner and outer periphery sides are connected, they form intermittent circles with different diameters. In other words, the multiple electrode portions 53 are configured by equally dividing a ring surrounding the divided inner frame portion 51 at a predetermined interval.

[0039] As shown in FIG. 6, the electrode portions 53 each have an electrode film 531 formed on the upper surface. The electrode portions 53 can be electrically connected to an external circuit board or the like (not shown) by connecting wires (not shown) to the electrode film 531. When the micro-vibrator 2 is mounted, each of the electrode portions 53 is spaced a predetermined distance from the rim 211 of the micro-vibrator 2 as shown in FIG. 1 or FIG. 8, and each of the electrode portions 53 forms a capacitor with the micro-vibrator 2. That is, the mounting substrate 3 can detect the electrostatic capacitance between the micro-vibrator 2 and the mounting substrate 3 through the electrode portions 53, generate electrostatic attraction between the micro-vibrator 2 and the mounting substrate 3, and vibrate the micro-vibrator 2 in a wine glass mode.

[0040] Note that Figure 1 etc. shows an example in which 16 electrode portions 53 are evenly arranged on the mounting substrate 3, spaced apart from each other to form a ring; however, this is not limited to this, and the number and arrangement of the electrode portions 53 can be changed as appropriate depending on the shape, size, etc. of the micro-vibration body 2.

[0041] The split outer frame portion 54 is, for example, configured such that a frame body surrounding the split inner frame portion 51 in top view is divided into multiple portions by grooves 55, and has an electrode film 541 made of Al or the like on its upper surface as shown in Fig. 5 and Fig. 7. The multiple split outer frame portions 54 are, for example, electrically connected to different split inner frame portions 51 via different bridge wirings 42, and a wire (not shown) is connected to the electrode film 541. As a result, the multiple split outer frame portions 54 are electrically connected to an external circuit board (not shown) or the like, and enable potential control and voltage detection of the surface electrode 23 of the micro-vibrator 2 via the split outer frame portion 54 by an external power source (not shown) or the like.

[0042] Among the split outer frame parts 54, those connected to the voltage detection wiring 42B are configured to be electrically independent from at least the split outer frame part 54 connected to the voltage application wiring 42A. Furthermore, the split outer frame parts 54 are not limited to the example shown in Fig. 5 in which four are formed, and the number, arrangement, shape, dimensions, etc., of the split outer frame parts 54 can be appropriately changed depending on the number of bridge wirings 42, etc.

[0043] The bonding member 52 is a conductive material used for bonding the micro-vibrator 2 and the mounting substrate 3, and electrically connects the electrode connection portion 421 of the bridge wiring 42 and the surface electrode 23 of the micro-vibrator 2. The bonding member 52 is a conductive paste material made of a conductive material such as AuSn (gold tin), Ag (silver), or Au, and is applied to the electrode connection portion 421 using a syringe or the like. The bonding member 52 is disposed on each of the electrode connection portions 421 of the mounting substrate 3, but is disposed so as not to straddle at least the electrode connection portion 421 of the voltage detection wiring 42B and the electrode connection portion 421 of the voltage application wiring 42A, as shown in FIG. 8, for example. This is to prevent the voltage detection wiring 42B from being directly connected to the voltage application wiring 42A by the bonding member 52, making it impossible to distinguish between the applied voltage of the surface electrode 23 and the applied voltage of the voltage application wiring 42A.

[0044] That is, as shown in FIG. 13, the mounting structure 1 is a structure in which a voltage application wiring 42A and a voltage detection wiring 42B are connected to different positions of the surface electrode 23 of the micro-vibrator 2, and the wirings 42A and 42B are not directly connected but are electrically connected via the surface electrode 23. These wirings 42A and 42B are connected to external terminals, respectively, and voltage application and voltage detection from the outside are possible without contacting any part of the surface electrode 23 other than the joint with the mounting board 3. Even if the micro-vibrator 2 is sealed with a lid material (not shown), the wirings 42A and 42B are connected to external terminals, so that voltage application and voltage detection of the surface electrode 23 are possible. The multiple electrode parts 53 of the mounting board 3 have a driving electrode for driving in the wine glass mode and a detection electrode for detecting electrostatic capacitance, and are connected to the outside by wires (not shown) and face the part of the surface electrode 23 that covers the rim 211. In addition, in order to make it easier to see, Figure 13 shows an example configuration in which one voltage application wiring 42A and one voltage detection wiring 42B are connected to the surface electrode 23, but it is sufficient that there is at least one each of the wirings 42A and 42B, and the present invention is not limited to this example.

[0045] The mounting board 3 can be manufactured, for example, by the following process.

[0046] First, a lower substrate 4 made of, for example, borosilicate glass is prepared, and an annular groove 41 is formed by wet etching using buffered hydrofluoric acid. Then, a bridge wiring 42 that straddles the groove 41 and has an electrode connection portion 421 on the inside of the planned position for forming the divided inner frame portion 51 is formed by a lift-off method using a film formed by sputtering of Al. The thickness of the bridge wiring 42 is, for example, about 0.1 μm.

[0047] Next, for example, a Si substrate (later upper substrate 5) made of Si is prepared and anodically bonded to the borosilicate glass lower substrate 4. Next, grooves that partition the regions that will later become divided inner frame portion 51, multiple electrode portions 53, and divided outer frame portion 54 are formed in the Si substrate by a known etching method.

[0048] Specifically, for example, trench etching is performed by DRIE (short for Deep Reactive Ion Etching) to partially expose lower substrate 4 and separate divided inner frame portion 51, multiple electrode portions 53, and divided outer frame portion 54. As a result, the Si substrate becomes upper substrate 5 including divided inner frame portion 51, multiple electrode portions 53, and divided outer frame portion 54 that are spaced apart from one another. Also, grooves 41 formed in lower substrate 4 are exposed from upper substrate 5 by this Si substrate partitioning process.

[0049] Finally, for example, electrode films 531, 541 are formed on the upper surfaces of the plurality of electrode portions 53 and the divided outer frame portion 54 by sputtering or the like. As a result of these steps, the mounting substrate 3 having the above-described structure is obtained. When the micro-vibration body 2 is mounted on the mounting substrate 3, the bonding member 52 is disposed on the electrode connection portion 421 of the lower substrate 4.

[0050] 5 and the like can be obtained, for example, by forming areas on a wafer that will become a plurality of mounting substrates 3 having the above-described structure, and then dividing the wafer into individual pieces by dicing, etc. In other words, the mounting substrate 3 can be manufactured at the wafer level.

[0051] The mounting substrate 3 manufactured by the above-mentioned process is fixed by suction to a mounter device (not shown), the micro-vibrator 2 is transported by a transport device (not shown), the mounting surface 22b of the connection portion 22 is brought into contact with the bonding member 52, and the bonding member 52 is solidified, thereby mounting the micro-vibrator 2. For example, the micro-vibrator 2 can be transported by bringing a gripping mechanism capable of vacuum suction of a transport device (not shown) into contact with the suction surface 22a of the micro-vibrator 2 and performing vacuum suction. The mounting substrate 3 is then heated by a heating mechanism of the mounter device (not shown), the micro-vibrator 2 is cooled after mounting, and the bonding member 52 is solidified, thereby bonding the micro-vibrator 2 to the mounting substrate 3.

[0052] The alignment of the micro-vibrator 2 with respect to the mounting substrate 3 can be performed, for example, by imaging the micro-vibrator 2 and the mounting substrate 3 and extracting feature points by edge detection using a known image processing technique, thereby adjusting the relative position.

[0053] The above is the basic configuration of the mounting structure 1 for the micro-vibrator 2. When the mounting structure 1 configures a BRG, during operation, an electrostatic attraction is generated between some of the multiple electrode parts 53 and the micro-vibrator 2, causing the micro-vibrator 2 to vibrate in a wine glass mode. When an external Coriolis force is applied to this BRG while the micro-vibrator 2 is in a vibrating state, the micro-vibrator 2 is displaced, causing the node position of the vibration mode to change. This BRG detects the change in the node of the vibration mode by the electrostatic capacitance between the micro-vibrator 2 and the multiple electrode parts 53, making it possible to detect the angular velocity acting on the BRG.

[0054] According to this embodiment, the surface electrode 23 of the micro-vibrator 2 is formed on the mounting substrate 3 and connected to the voltage application wiring 42A and the voltage detection wiring 42B that are electrically independent from each other, and the mounting structure 1 can be electrically connected to the outside via these bridge wirings 42. Therefore, after the micro-vibrator 2 is connected to the mounting substrate 3, the voltage of the surface electrode 23 of the micro-vibrator 2 can be detected via the voltage detection wiring 42B. This makes it unnecessary to directly probe the parts of the surface electrode 23 other than the joint with the mounting substrate 3 in the voltage detection of the surface electrode 23, and the mounting structure 1 can prevent the base material of the micro-vibrator 2 and the surface electrode 23 from being damaged and the resulting decrease in the Q value. In addition, the BRG including this mounting structure 1 simplifies the inspection process of the applied voltage of the surface electrode 23 and enables the detection of failures caused by the joint state between the micro-vibrator 2 and the mounting substrate 3, thereby improving the yield, improving reliability, and reducing manufacturing costs.

[0055] (Modification of the first embodiment) In the mounting substrate 3, a plurality of dividing grooves 43 separating the electrode connecting portions 421 may be formed in an inner frame region R2 surrounded by a plurality of divided inner frame portions 51, as shown in FIG.

[0056] 14, similarly to Fig. 10, in order to make it easier to understand the configuration of the bridge wiring 42 and the divided inner frame portion 51 of the mounting board 3, a predetermined region including the divided inner frame portion 51 is shown, and other components of the mounting board 3 are omitted. In addition, although Fig. 14 does not show a cross section, the bridge wiring 42 is hatched. The same applies to Figs. 20 and 23 described below.

[0057] The dividing grooves 43 are formed near each of the electrode connecting parts 421 so that when the bonding member 52 that bonds the micro-vibrator 2 and the electrode connecting parts 421 of the mounting substrate 3 spreads, an excess part of the bonding member 52 flows into the dividing grooves 43. For example, the number of dividing grooves 43 is the same as the number of the electrode connecting parts 421, and the dividing grooves 43 are arranged at a distance from each other to be configured as separate and independent. As shown in FIG. 15, for example, the dividing grooves 43 serve to prevent different electrode connecting parts 421 from being electrically connected directly to each other by the bonding member 52 by allowing the excess part of the bonding member 52 arranged on each electrode connecting part 421 to flow into the dividing grooves 43. This makes it possible to more reliably prevent the voltage application wiring 42A and the voltage detection wiring 42B from being directly connected to each other, and it becomes possible to stably detect the voltage of the surface electrode 23 of the micro-vibrator 2. In addition, a part of the mounting surface 22b of the micro-vibrator 2 abuts against a part of the inner frame region R2 of the mounting substrate 3, and the mounting surface 22b also serves as an abutting portion against the mounting substrate 3.

[0058] The number, arrangement, shape, width, depth, and other dimensions of the division grooves 43 may be appropriately changed as long as the division grooves 43 are separated from the division grooves 42A and the voltage detection wiring 42B. The division grooves 43 may be formed in the same process as the grooves 41, or may be formed in a separate process from the grooves 41 by wet etching or the like.

[0059] This modified example also provides the mounting structure 1 with the same effects as those of the first embodiment. In addition, since the mounting substrate 3 has the division grooves 43, it is possible to more reliably prevent the voltage application wiring 42A and the voltage detection wiring 42B from being directly connected to each other due to the joining member 52 wrapping around them, which can result in poor insulation.

[0060] Second embodiment The mounting structure 1 of the second embodiment will be described with reference to the drawings.

[0061] 16 and 20, in order to make it easier to understand the bonding state between the micro-vibrator 2 and the mounting substrate 3, only a predetermined region of the mounting substrate 3 including the divided inner frame portion 51 is shown, and other portions of the mounting substrate 3 are omitted. In order to make it easier to see, in Figs. 16 to 19 and 21, only a portion of the configuration of the micro-vibrator 2 on the mounting surface 22b side of the connection portion 22 is shown, and other portions of the micro-vibrator 2 are omitted. In addition, in Figs. 16 to 19, in order to make it easier to understand the pattern shape of the surface electrode 23, although a cross section is not shown, the surface electrode 23 is hatched and some outer contours that cannot be seen from the angle shown in the drawings are shown by dashed lines.

[0062] In the mounting structure 1 of the present embodiment, as shown in Fig. 16, for example, the portion of the surface electrode 23 of the micro-vibrator 2 that covers the side wall surface of the connection portion 22 is a branched electrode 231. In this mounting structure 1, the multiple branch electrodes 231 of the micro-vibrator 2 are each connected to different divided inner frame portions 51 of the mounting substrate 3 via a joining member 52. This mounting structure 1 differs from the first embodiment in the above-mentioned respects. In this embodiment, this difference will be mainly described.

[0063] In the present embodiment, the micro-vibrator 2 has a mounting surface 22b of the connection portion 22 exposed from the surface electrode 23, and a plurality of branch electrodes 231 of the surface electrode 23 are joined to the mounting substrate 3 by a joining member 52. The micro-vibrator 2 has a plurality of branch electrodes 231 connected to electrode connection portions 421 of different bridge wirings 42 by the joining member 52. In the present embodiment, the micro-vibrator 2 has a portion of a side wall surface 22c (hereinafter simply referred to as "side wall surface 22c") on the rear surface 2b side of the connection portion 22 that is sandwiched between adjacent branch electrodes 231 exposed from the surface electrode 23. As a result, the mounting structure 1 of this embodiment also has an electrical connection structure similar to that of the first embodiment shown in FIG. 13.

[0064] 17, in this embodiment, the surface electrode 23 has a branch electrode 231 in a position corresponding to the multiple divided inner frame portions 51 of the mounting substrate 3, near the lower end, which is the end of the side wall surface 22c on the mounting surface 22b side. In other words, the surface electrode 23 has the branch electrodes 231 branched out in the same number as the divided inner frame portions 51 to which the bridge wiring 42 is connected, for example.

[0065] 16, the width of the branch electrode 231 is made smaller than the width of the divided inner frame portion 51 so that the branch electrode 231 is not directly connected to other adjacent branch electrodes 231 via the bonding member 52. The branch electrode 231 is formed by forming a film on the surface electrode 23 by vacuum film formation such as sputtering in a state where a cap mask CP made of any material such as metal or resin is attached to the mounting surface 22b side of the connection portion 22 as shown in FIG.

[0066] The mounting structure 1 of this embodiment also provides the same effects as those of the first embodiment.

[0067] (Modification of the second embodiment) The mounting structure 1 may be configured to have a bottom surface protrusion 24 for positioning with the mounting substrate 3 on the mounting surface 22b as shown in Fig. 19. In this case, the mounting substrate 3 is configured to have a fitting recess 44 that fits with the bottom surface protrusion 24 of the micro-vibrator 2 within the facing region R1 as shown in Fig. 20.

[0068] The bottom surface protrusion 24 of the micro-vibration body 2 can be formed, for example, by preparing a mold M shown in Fig. 4A having a protrusion on the tip surface of the support part M2, and going through the same process as that described in the first embodiment. The bottom surface protrusion 24 has a configuration in which one of the branch electrodes 231 is extended on its surface, as shown in Fig. 19, for example, but is not limited to this, and may be exposed from the surface electrode 23. The former surface electrode 23 can be formed by using a cap mask CP having a groove that connects a part of the bottom surface protrusion 24 and one of the parts of the side wall surface 22c of the connection part 22 where the branch electrode 231 is to be formed.

[0069] As shown in FIG. 21, for example, the fitting recess 44 has an inner diameter approximately equal to the outer diameter of the bottom surface protrusion 24 and a depth at least equal to the height of the bottom surface protrusion 24 so that the micro-vibrator 2 can be fitted into the bottom surface protrusion 24 when the micro-vibrator 2 is placed on the mounting substrate 3. The fitting recess 44 is formed by wet etching or the like, similarly to the groove 41. Note that, as shown in FIG. 22, for example, the mounting substrate 3 may have a configuration having a plurality of division grooves 43 separating the fitting recess 44 and the electrode connection portion 421 in addition to the fitting recess 44. Note that the micro-vibrator 2 is an abutment portion in which a portion of the mounting surface 22b located around the bottom surface protrusion 24 is abutted against a portion of the mounting substrate 3 located outside the fitting recess 44 or outside the division grooves 43 in the inner frame region R2.

[0070] This modification also provides a mounting structure 1 that can obtain the same effects as those of the second embodiment. Moreover, according to this modification, the micro-vibrator 2 has the bottom surface convex portion 24, and the mounting substrate 3 has the fitting concave portion 44, so that the positioning of the micro-vibrator 2 and the mounting substrate 3 is simplified, the yield is further improved, and the mounting structure 1 has higher connection reliability. Furthermore, when the mounting substrate 3 has a plurality of dividing grooves 43, the same effects as those of the modification of the first embodiment can be obtained.

[0071] Third embodiment The mounting structure 1 of the third embodiment will be described with reference to the drawings.

[0072] 23, in order to make it easier to understand the bonded state between the micro-vibrator 2 and the mounting substrate 3, only a predetermined region of the micro-vibrator 2 including the connection portion 22 and a predetermined region of the mounting substrate 3 including the divided inner frame portion 51 are shown, and other portions of the micro-vibrator 2 and the mounting substrate 3 are omitted. In Fig. 24, only a predetermined region of the mounting substrate 3 including the divided inner frame portion 51 is shown, and other portions of the mounting substrate 3 are omitted.

[0073] 23, the mounting structure 1 of this embodiment differs from the above-described first embodiment in that the surface electrode 23 of the micro-vibrator 2 and the electrode connection portion 421 of the mounting substrate 3 are in contact with each other and directly joined without the use of a joining member 52. In this embodiment, this difference will be mainly described.

[0074] In this embodiment, the surface electrode 23 is joined to the electrode connection portion 421 of the mounting substrate 3 without any other member such as the joining member 52. The surface electrode 23 and the electrode connection portion 421 are made of conductive materials that can diffuse into each other, such as, but not limited to, Al and Cu, and are joined by using diffusion bonding.

[0075] The surface electrode 23 can be bonded to the electrode connection part 421 by, for example, the following process. For example, in order to prevent the bonding surface between the surface electrode 23 and the electrode connection part 421 from being oxidized, the micro-vibrator 2 is mounted on the mounting substrate 3 under an environment such as a reduced pressure or an inert gas atmosphere, and the surface electrode 23 is brought into contact with the electrode connection part 421. Then, while applying pressure to the electrode connection part 421 by the surface electrode 23, the mounting substrate 3 is heated so that the surface electrode 23 and the electrode connection part 421 are at a temperature equal to or higher than the eutectic point and lower than the melting point of these constituent materials. As a result, the constituent materials of the surface electrode 23 and the electrode connection part 421 diffuse into the bulk of the other at the contact part, forming a eutectic layer. At this time, a secondary pressurization with a pressure higher than the initial pressurization may be performed as necessary. Thereafter, by cooling, the surface electrode 23 and the electrode connection part 421 are directly bonded to each other without passing through a liquid phase and without any other member.

[0076] In addition, the bonding between the surface electrode 23 and the electrode connection portion 421 in this embodiment can be called "direct bonding", "solid-phase bonding", "eutectic bonding", "diffusion bonding", or the like.

[0077] The present embodiment also provides the mounting structure 1 with the same effects as those of the first embodiment. Moreover, since the present embodiment does not use the joining member 52, the voltage application wiring 42A and the voltage detection wiring 42B are not directly connected to each other, and therefore, insulation failure can be more reliably prevented.

[0078] (Modification of the third embodiment) 24, the mounting substrate 3 may have an auxiliary electrode 45 in an area R1 facing the micro-vibrator 2 and surrounded by a plurality of electrode connection parts 421. The auxiliary electrode 45 is disposed, for example, at a distance from all the electrode connection parts 421 and is electrically independent of the electrode connection parts 421. The auxiliary electrode 45 increases the bonding area with the surface electrode 23 of the micro-vibrator 2 and serves to improve the bonding strength between the micro-vibrator 2 and the mounting substrate 3. The auxiliary electrode 45 may be connected to the voltage application wiring 42A or the voltage detection wiring 42B as long as the voltage application wiring 42A and the voltage detection wiring 42B are electrically independent of each other.

[0079] This modification also provides the mounting structure 1 with the same effects as those of the third embodiment. Moreover, this modification provides the effect of improving the bonding strength between the micro-vibrator 2 and the mounting substrate 3 by the auxiliary electrode 45, thereby further improving the bonding reliability.

[0080] (Other embodiments) Although the present disclosure has been described based on the embodiment, it is understood that the present disclosure is not limited to the embodiment or structure. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and forms, and other combinations and forms including only one element, more than one, or less than one, are also within the scope and concept of the present disclosure.

[0081] (1) For example, the mounting structure 1 may be configured such that the micro-vibrator 2 does not have the branch electrode 231, but has the bottom surface convex portion 24, and the mounting substrate 3 has the fitting concave portion 44. In this case, the mounting substrate 3 may have a plurality of dividing grooves, or the electrode connection portion 421 may be directly joined to the surface electrode 23 without the joining member 52. In this way, the mounting structure 1 may be configured by freely combining the components of the above-described embodiments and their modified examples, except when they are clearly incompatible.

[0082] (2) In addition, as shown in FIG. 25, the mounting structure 1 may have an electrode portion 53 of the mounting substrate 3 formed only with the metal wiring 532 without having a base portion constituting the upper substrate 5. In this case, the electrode portion 53 is a portion of the metal wiring 532 facing the lower surface 211a of the rim 211 of the micro-vibrator 2, and can vibrate the curved surface portion 21 of the micro-vibrator 2 in the z direction. The lower surface 211a of the rim 211 is a surface of the rim 211 connecting the front surface 2a and the back surface 2b of the micro-vibrator 2, and is a portion facing the mounting substrate 3. In addition, the mounting structure 1 may have a configuration in which the voltage application wiring 42A and the voltage detection wiring 42B are connected to a conductive film 46 formed on the lower substrate 4, instead of the divided outer frame portion 54 formed at the base portion of the upper substrate 5, and the conductive film 46 serves as a terminal portion. The conductive film 46 may be integral with the wiring 42 or may be separate from the wiring 42.

[0083] (3) The mounting structure 1 may be configured such that the mounting substrate 3 on which the micro-vibrator 2 is mounted does not have a divided inner frame portion 51, as shown in Fig. 26, for example. In this case, the micro-vibrator 2 may be joined to the electrode connection portion 421 of the wiring 42 via a joining member 52, as shown in Fig. 27, for example, or the surface electrode 23 and the electrode connection portion 421 of the wiring 42 may be directly joined, as shown in Fig. 28. In the former case, it is more preferable that the mounting substrate 3 has a dividing groove 43 between the electrode connection portions 421, from the viewpoint of directly connecting the voltage application wiring 42A and the voltage detection wiring 42B with the joining member 52.

[0084] (4) In the mounting structure 1, as shown in Fig. 29, for example, the electrode connection portion 421 of the wiring 42 does not extend to the facing region R1 of the mounting substrate 3 facing the connection portion 22 of the micro-vibrator 2, and may be connected to the surface electrode 23 via a bonding member 52 and a divided inner frame portion 51. In this case, the wiring 42 is configured such that, for example, one end is only extended to just below the divided inner frame portion 51 or to the outside of the facing region R1, and does not protrude into the facing region R1 or a region inside the divided inner frame portion 51. In this case, the divided inner frame portion 51 is made of, for example, conductive silicon, and electrically connects the wiring 42 and the surface electrode 23 together with the bonding member 52.

[0085] (5) It goes without saying that in each of the above embodiments, the elements constituting the embodiment are not necessarily essential, except when expressly stated as essential or when it is clearly considered essential in principle. In addition, in each of the above embodiments, when the numbers, values, amounts, ranges, etc. of the components of the embodiment are mentioned, they are not limited to the specific numbers, except when expressly stated as essential or when it is clearly limited to a specific number in principle. In addition, 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., except when expressly stated as essential or when it is clearly limited to a specific shape, positional relationship, etc. in principle. [Explanation of symbols]

[0086] 2... Micro-vibration body, 21... Curved surface portion, 22... Connection portion, 22b... Mounting surface, 22c side wall surface, 23 surface electrode, 231 branch electrode, 24 bottom convex portion, 3... mounting board, 42... wiring, 42A... voltage application wiring, 42B: Voltage detection wiring; 421: Electrode connection portion; 43: Dividing groove; 44 fitting recess, 51 divided inner frame portion, 52 joining member, 53 electrode, R1...Opposing area, R2...Inner frame area

Claims

1. A mounting structure for a micro-vibrator, A micro-vibration body (2) having a curved surface portion (21) having a three-dimensional curved surface of a hemispherical shape, a connection portion (22) extending from the curved surface portion toward the center of the hemispherical shape, and a surface electrode (23) covering the connection portion and at least a part of the curved surface portion; A mounting substrate (3) having two or more wirings (42) and to which a part of the micro-vibrator is connected, One end of the wiring is an electrode connection portion (421) that is connected to a portion of the surface electrode that covers the connection portion, The two or more wirings each include at least one voltage application wiring (42A) for applying a voltage to the surface electrode and at least one voltage detection wiring (42B) for detecting the voltage applied to the surface electrode; The voltage detection wiring is disposed at a distance from the voltage application wiring on the mounting substrate.

2. 2. The mounting structure of a micro-vibrator according to claim 1, wherein said mounting substrate is formed with a dividing groove (43) for separating said voltage detection wiring and said voltage application wiring.

3. a portion of the surface electrode covering a side wall surface (22c) of the connection portion is a branch electrode (231) that is branched into the same number as or more than the electrode connection portions and is disposed at a position corresponding to the electrode connection portions; The micro-vibrator has a side wall surface, and an area between the adjacent branch electrodes is exposed from the surface electrode.

3. The mounting structure of the micro-vibrator according to claim 1, wherein the plurality of electrode connection parts are connected to different branch electrodes via joint members (52).

4. The micro-vibrator has a bottom surface convex portion (24) on a mounting surface (22b) which is a bottom surface of the connection portion, 4. A mounting structure for a micro-vibrator as described in any one of claims 1 to 3, wherein an area of ​​the mounting substrate facing the connection portion of the micro-vibrator is defined as an opposing area (R1), and the mounting substrate has an engagement recess (44) in the opposing area into which the bottom convex portion fits.

5. 5. The mounting structure for a micro-vibrator according to claim 1, wherein the electrode connection portion abuts against a part of the surface electrode and is joined to the surface electrode without any other member therebetween.

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