Capacitive acceleration sensor

Abstract

To provide a capacitive acceleration sensor that can improve its detection accuracy.SOLUTION: A capacitive acceleration sensor 1 comprises a rotation structure unit 30 that rotates around a rotation center, a translation structure unit 40 that translates in an intersecting axis direction, and a detection structure unit 100 that detects a capacitance. The rotation structure unit 30 has a weight part 35 that generates weight asymmetry. The translation structure unit 40 has a first surface 40A, and a second surface 40B on the opposite side. The detection structure unit 100 has a first electrode group and a second electrode group. The first electrode group includes a first electrode E1L and a second electrode E2L arranged side by side in a sensitivity axis direction. The second electrode group includes a first electrode E1R and a second electrode E2R arranged side by side in the sensitivity axis direction. The first electrode E1L and the first electrode E1R are arranged opposite to each other across the translation structure unit 40 along the intersecting axis direction. On the other side in the sensitivity axis direction relative to the rotation center D, the second electrode E2L and the second electrode E2R are arranged opposite to each other across the translation structure unit 40 along the intersecting axis direction.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a capacitance type acceleration sensor. [Background technology]

[0002] The electrostatic capacitance type acceleration sensor includes a movable structure that moves in response to acceleration, and a detection structure that detects electrostatic capacitance generated between the movable structure and the detection structure.

[0003] For example, Patent Document 1 discloses a capacitive acceleration sensor including an electrode and a seesaw structure as a counter electrode for the electrode. The seesaw structure has a rotatable support element, a mass element that generates mass asymmetry, and an electrode element disposed on the support element to provide an auxiliary capacitance for canceling a change in capacitance due to lateral acceleration. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] DE 102006051329 A1 Summary of the Invention [Problem to be solved by the invention]

[0005] When the capacitance changes based on acceleration not only in the sensitivity axis direction but also in the cross axis direction, as in the capacitance-type acceleration sensor described in Patent Document 1, the detection accuracy of acceleration in the sensitivity axis direction may decrease due to the cross sensitivity to acceleration in the cross axis direction.

[0006] The present invention has been made in view of the above circumstances, and has an object to provide a capacitance type acceleration sensor capable of improving detection accuracy. [Means for solving the problem]

[0007] A capacitive acceleration sensor according to one aspect of the present invention is a capacitive acceleration sensor for detecting acceleration in a sensitivity axis direction, and includes a rotation structure that rotates around a rotation center due to acceleration in the sensitivity axis direction, a translation structure that translates in the intersecting axis direction due to acceleration in the intersecting axis direction intersecting the sensitivity axis direction, and a detection structure that detects capacitance generated between the translation structure and the rotation structure. The rotation structure has a weight portion that generates mass asymmetry, and the weight portion is aligned with the translation structure in the intersecting axis direction. The translation structure has a first surface opposite to the side on which the weight portion is arranged and a second surface opposite to the first surface. The detection structure is a rotation structure having a weight portion that generates mass asymmetry and is aligned with the translation structure in the intersecting axis direction. The rotation center has a first electrode group arranged opposite a first surface of the structure and a second electrode group arranged opposite a second surface of the translation structure, the first electrode group includes a first electrode and a second electrode aligned in the sensitivity axis direction, the second electrode group includes a first electrode and a second electrode aligned in the sensitivity axis direction, and on one side of the sensitivity axis direction from the center of rotation, the first electrode of the first electrode group and the first electrode of the second electrode group are arranged opposite each other along the cross axis direction with the translation structure therebetween, and on the other side of the sensitivity axis direction from the center of rotation, the second electrode of the first electrode group and the second electrode of the second electrode group are arranged opposite each other along the cross axis direction with the translation structure therebetween. Effect of the Invention

[0008] According to the present invention, it is possible to provide a capacitance type acceleration sensor capable of improving detection accuracy. [Brief description of the drawings]

[0009] [Figure 1] 1 is a plan view of a capacitance-type acceleration sensor according to a first embodiment. [Diagram 2] 1 is a cross-sectional view of a capacitance-type acceleration sensor according to a first embodiment. [Diagram 3] FIG. 2 is a plan view showing a change in the capacitance-type acceleration sensor when it is subjected to acceleration in the Z-axis direction. [Figure 4] 4 is a cross-sectional view showing a change in the capacitance type acceleration sensor when subjected to acceleration in the Z-axis direction. FIG. [Diagram 5]FIG. 2 is a plan view showing a change in the capacitance-type acceleration sensor when it is subjected to acceleration in the X-axis direction. [Figure 6] 4 is a cross-sectional view showing a change in the capacitance type acceleration sensor when it is subjected to acceleration in the X-axis direction. FIG. [Figure 7] 11 is a cross-sectional view showing the change in the translation structure when subjected to acceleration in the X-axis and Z-axis directions. [Figure 8] FIG. 4 is a diagram illustrating a part of servo control in the first embodiment. [Figure 9] FIG. 4 is a diagram illustrating a part of servo control in the first embodiment. [Figure 10] FIG. 11 is a plan view of a capacitive acceleration sensor according to a second embodiment. [Figure 11] FIG. 11 is a cross-sectional view of a capacitance-type acceleration sensor according to a second embodiment. [Figure 12] FIG. 13 is a plan view of a capacitive acceleration sensor according to a third embodiment. [Figure 13] FIG. 11 is a cross-sectional view of a capacitance-type acceleration sensor according to a third embodiment. [Figure 14] FIG. 13 is a plan view of a capacitive acceleration sensor according to a fourth embodiment. [Figure 15] FIG. 13 is a cross-sectional view of a capacitance-type acceleration sensor according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described. In the following description of the drawings, the same or similar components are represented by the same or similar reference numerals. The drawings are illustrative, and the dimensions and shapes of each part are schematic, and the technical scope of the present invention should not be interpreted as being limited to the embodiment.

[0011] In order to clarify the mutual relationships between the drawings and to aid in understanding the positional relationships of the various components, an orthogonal coordinate system consisting of X-axis, Y-axis, and Z-axis may be conveniently attached to each drawing. The X-axis, Y-axis, and Z-axis correspond to each other in each drawing.

[0012] In the following description, the direction parallel to the X-axis is referred to as the "X-axis direction", the direction parallel to the Y-axis is referred to as the "Y'-axis direction", and the direction parallel to the Z'-axis is referred to as the "Z'-axis direction". The directions of the tips of the arrows on the X-axis, Y-axis, and Z-axis are referred to as "positive" or "+ (plus)", and the directions opposite to the arrows are referred to as "negative" or "- (minus)". For convenience, the +Z-axis direction will be described as the upward direction and the -Z-axis direction as the downward direction, but the up and down directions of the capacitive acceleration sensor 1 are not limited to these directions. The plane specified by the X-axis and Z-axis is referred to as the ZX plane, and the same applies to the planes specified by the other axes.

[0013] First Embodiment

[0014] First, the configuration of a capacitance type acceleration sensor 1 according to the first embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a plan view of the capacitance type acceleration sensor according to the first embodiment. Fig. 2 is a cross-sectional view of the capacitance type acceleration sensor according to the first embodiment. Fig. 1 shows the capacitance type acceleration sensor 1 as viewed from the positive Z-axis side (hereinafter simply referred to as "planar view"), and Fig. 2 shows the capacitance type acceleration sensor 1 as viewed from the positive Y-axis side (hereinafter simply referred to as "cross-sectional view").

[0015] The capacitance type acceleration sensor 1 includes a detection structure 100, a rotation structure 30, a translation structure 40, a support 50, and a substrate 60. The capacitance type acceleration sensor 1 is an acceleration sensor that detects acceleration in the Z-axis direction. The Z-axis direction corresponds to an example of a sensitivity axis direction, and the X-axis direction corresponds to an example of a cross axis direction. When subjected to acceleration in the Z-axis direction and the X-axis direction, the rotation structure 30 rotates around a rotation axis extending in the Y-axis direction as a rotation center D, and the translation structure 40 connected to the rotation structure 30 is pulled by the rotation structure 30 and twisted. When subjected to acceleration in the X-axis direction, the rotation structure 30 translates in the X-axis direction, and the translation structure 40 connected to the rotation structure 30 is pulled by the rotation structure 30 and translated in the X-axis direction.

[0016] The detection structure 100 detects the electrostatic capacitance generated between the detection structure 100 and the translation structure 40. The detection structure 100 includes a first detection structure 10, a first support 10P, a second detection structure 20, and a second support 20P. The first detection structure 10 and the second detection structure 20 are provided inside an opening 39 of the rotation structure 30, which will be described later. The first detection structure 10, the translation structure 40, the second detection structure 20, and a weight section 35, which will be described later, are arranged in this order with a gap in between in the X-axis direction. The first detection structure 10 and the second detection structure 20 are held with a gap between them and the rotation structure 30 and the translation structure 40.

[0017] The first detection structure 10 includes a substrate 11 and electrodes E1L, E2L, E11, and E12.

[0018] The shape of the base material 11 is, for example, a cube. The base material 11 has surfaces 11A and 11B extending along the YZ plane, surfaces 11C and 11D extending along the XY plane, and surfaces 11E and 11F extending along the ZX plane. The surface 11A is provided on the negative X-axis direction side and faces a side wall portion 34 described later with a gap therebetween. The surface 11B is provided on the positive X-axis direction side and faces a translation structure portion 40 with a gap therebetween. The surface 11C is provided on the negative Z-axis direction side and faces a holding plate portion 31 described later with a gap therebetween. The surface 11D is provided on the positive Z-axis direction side. The surface 11E is provided on the negative Y-axis direction side and faces a side wall portion 32 described later with a gap therebetween. The surface 11F is provided on the positive Y-axis direction side and faces a side wall portion 33 described later with a gap therebetween. The material of the base material 11 is, for example, silicon oxide such as SiO2.

[0019] The shape of the substrate 11 is not limited to the above, and may be a polyhedron, a sphere, a cylinder, a cone, or a combination of these. The material of the substrate 11 is not limited to silicon oxide as long as it can insulate the electrodes E1L and E2L. The material of the substrate 11 may be an inorganic insulator such as silicon nitride (Si3N4), silicon oxynitride (Si2N2O), aluminum oxide (Al2O3), aluminum nitride (AlN), beryllium oxide (BeO), and glass (SiO2). The material of the substrate 11 may be an organic insulator such as imide resin, amide resin, styrene resin, epoxy resin, and acrylic resin. The material of the substrate 11 may be a combination of these. The substrate 11 may be a semiconductor or a conductor having an insulating film coated on its surface.

[0020] The electrode E1L has a capacitance C 1L The electrode E2L generates a capacitance C between the electrode E2L and the translation structure 40. 2L In addition, the electrodes E1L and E2L have a capacitance C 1L ,C 2L The electrodes E1L and E2L are disposed facing a surface 40A of the translation structure 40, which will be described later. The electrodes E1L and E2L are arranged in the Z-axis direction with a gap therebetween, and the electrode E1L is provided on the Z-axis positive side of the electrode E2L. The electrode E1L is located on the Z-axis positive side of the rotation center D, and the electrode E2L is located on the Z-axis negative side of the rotation center D. The electrodes E1L and E2L are provided in a strip shape on the surface 11B of the base material 11 from the end on the surface 11E side to the end on the surface 11F side. The materials of the electrodes E1L and E2L are, for example, metals such as gold (Au), silver (Ag), copper (Cu), aluminum (Al), titanium (Ti), tantalum (Ta), tungsten (W) and molybdenum (Mo), and semiconductors such as polysilicon (Poly-Si). The electrodes E1L and E2L correspond to an example of a first electrode group. The electrode E1L corresponds to an example of a first electrode in the first electrode group, and the electrode E2L corresponds to an example of a second electrode in the first electrode group.

[0021] The number and shape of the electrodes in the first electrode group are not limited to those described above, so long as the first electrode group includes a first electrode located on the positive Z-axis side of the rotation center D and a second electrode located on the negative Z-axis side of the rotation center D. The first electrode group may include three or more electrodes lined up in the Z-axis direction, or may include an electrode lined up in the Y-axis direction.

[0022] The electrodes E11 and E12 are electrodes for servo-controlling the rotation structure 30 by generating an electrostatic force that cancels the rotation and translation of the translation structure 40 and the rotation structure 30 based on the electrostatic capacitance detected in the first electrode group and the second electrode group. The electrodes E11 and E12 are arranged opposite to a side wall portion 34 of the rotation structure 30, which will be described later. The electrodes E11 and E12 are arranged in the Z-axis direction with a gap therebetween, and the electrode E11 is provided on the Z-axis positive side of the electrode E12. The electrodes E11 and E12 are provided in a strip shape on the surface 11A of the base material 11 from the end on the surface 11E side to the end on the surface 11F side. The area of ​​the electrodes E11 and E12 is larger than the area of ​​the electrodes E1L and E2L. From the viewpoint of increasing the electrostatic force to be generated, it is desirable that the area of ​​the electrodes E11 and E12 is large. Therefore, the electrodes E11 and E12 are provided on substantially the entire surface of the surface 11A except for the space between the electrodes E11 and E12. The electrodes E11 and E12 correspond to an example of a first control electrode.

[0023] As long as the rotating structure 30 can be servo-controlled, the number and shape of the electrodes in the first control electrode are not limited to the above. For example, the number of electrodes in the first control electrode may be one, or may be three or more. The first control electrode may have three or more electrodes arranged in the Z-axis direction, or may have electrodes arranged in the Y-axis direction.

[0024] The first support 10P supports the first detection structure 10. The first support 10P extends from the surface 11C of the base material 11 of the first detection structure 10 toward the negative Z-axis direction and is connected to the substrate 60. When viewed in a plan view, the area of ​​the first support 10P is smaller than the area of ​​the first detection structure 10. The shape of the first support 10P is, for example, a quadrangular prism having a surface parallel to the surfaces 11A, 11B, 11E, and 11F of the base material 11. However, the shape of the first support 10P is not limited to the above, and may be a rectangular prism, a cylindrical shape, a pyramidal shape, a cone shape, or a combination of these. The first support 10P is inserted into a through hole 31H formed in a holding plate portion 31 (described later) in the rotating structure 30 while maintaining a gap from the inner wall of the through hole 31H. The first support 10P is provided, for example, from the same material as the base material 11 of the first detection structure 10. Although not shown, extraction electrodes for electrically connecting the electrodes E1L, E2L, E11, and E12 to the substrate 60 are provided on the surface of the first pillar 10P.

[0025] The second detection structure 20 includes a substrate 21 and electrodes E1R, E2R, E12, and E22. The second detection structure 20 is configured symmetrically to the first detection structure 10 with respect to the YZ plane. Therefore, the description of the same configuration as the first detection structure 10 will be omitted as appropriate.

[0026] The base material 21 has surfaces 21A and 21B extending along the YZ plane, surfaces 21C and 21D extending along the XY plane, and surfaces 21E and 21F extending along the ZX plane. Surface 21A is provided on the negative X-axis direction side and faces translation structure 40 with a gap therebetween. Surface 21B is provided on the positive X-axis direction side and faces weight 35 (described later) with a gap therebetween. Surface 21C is provided on the negative Z-axis direction side and faces holding plate 31 (described later) with a gap therebetween. Surface 21D is provided on the positive Z-axis direction side. Surface 21E is provided on the negative Y-axis direction side and faces side wall 32 (described later) with a gap therebetween. Surface 21F is provided on the positive Y-axis direction side and faces side wall 33 (described later) with a gap therebetween. The material of base material 21 is the same as that of base material 11.

[0027] The electrode E1R has a capacitance C between it and the translation structure 40. 1R The electrode E2R generates a capacitance C between itself and the translation structure 40. 2R In addition, the electrodes E1R and E2R have a capacitance C 1R ,C 2R Detects. The electrodes E1R, E2R are arranged opposite to a surface 40B of the translation structure 40, which will be described later. The electrodes E1R, E2R are arranged in the Z-axis direction with a gap therebetween, and the electrode E1R is provided on the Z-axis positive side of the electrode E2R. The electrode E1R is located on the Z-axis positive side of the rotation center D, and the electrode E2R is located on the Z-axis negative side of the rotation center D. The electrodes E1R, E2R are provided in a strip shape on the surface 11B of the base material 11 from the end on the surface 11E side to the end on the surface 11F side. The material of the electrodes E1R, E2R is the same as the material of the electrodes E1L, E2L. The electrodes E1R, E2R correspond to an example of a second electrode group. The electrode E1R corresponds to an example of a first electrode in the second electrode group, and the electrode E2R corresponds to an example of a second electrode in the second electrode group.

[0028] The electrode E1R faces the electrode E1L along the X-axis direction, sandwiching the translation structure 40 therebetween. The electrode E2R faces the electrode E2L along the X-axis direction, sandwiching the translation structure 40 therebetween. Therefore, when the translation structure 40 translates and twists, a capacitance C 1L When increases, the capacitance C between the electrode E1R and the translation structure 40 increases. 1R decreases, and the capacitance C 1L When decreases, the capacitance C 1R increases. The capacitance C 2L ,C 2R The same is true.

[0029] The number and shape of the electrodes in the second electrode group are not limited to those described above, so long as the second electrode group includes a first electrode located on the positive side of the Z axis from the center of rotation D and a second electrode located on the negative side of the Z axis from the center of rotation D. The second electrode group may include three or more electrodes lined up in the Z axis direction, or may include an electrode lined up in the Y axis direction.

[0030] The electrodes E21 and E22 are electrodes for servo-controlling the rotation structure 30 by generating an electrostatic force that cancels the rotation and translation of the translation structure 40 and the rotation structure 30 based on the electrostatic capacitance detected in the first electrode group and the second electrode group. The electrodes E21 and E22 are arranged opposite to a side wall portion 34 of the rotation structure 30, which will be described later. The electrodes E21 and E22 are arranged in the Z-axis direction with a gap therebetween, and the electrode E21 is provided on the Z-axis positive side of the electrode E22. The electrodes E21 and E22 are provided in a strip shape on the surface 21B of the base material 21 from the end on the surface 21E side to the end on the surface 21F side. The area of ​​the electrodes E21 and E22 is larger than the area of ​​the electrodes E1R and E2R. From the viewpoint of increasing the electrostatic force to be generated, it is desirable that the area of ​​the electrodes E21 and E22 is large. Therefore, the electrodes E21 and E22 are provided on substantially the entire surface of the surface 21A except for the space between the electrodes E21 and E22. The electrodes E21 and E22 correspond to an example of a second control electrode.

[0031] As long as the rotating structure 30 can be servo-controlled, the number and shape of the electrodes in the second control electrode are not limited to the above. For example, the number of electrodes in the second control electrode may be one, or may be three or more. The second control electrode may have three or more electrodes arranged in the Z-axis direction, or may have electrodes arranged in the Y-axis direction.

[0032] The second support 20P supports the second detection structure 20. The second support 20P extends from the surface 21C of the base material 21 of the second detection structure 20 toward the Z-axis negative direction and is connected to the substrate 60. The shape and material of the second support 20P are the same as those of the first support 10P. The second support 20P is inserted into a through hole 31H formed in a holding plate portion 31 of the rotation structure 30, which will be described later, while maintaining a gap from the inner wall of the through hole 31H. Inside the through hole 31H, the first support 10P, the support portion 50, and the second support 20P are arranged in this order in the X-axis direction. Although not shown in the figure, an extraction electrode for electrically connecting the electrodes E1R, E2R, E21, and E22 to the substrate 60 is provided on the surface of the first support 10P.

[0033] The rotating structure 30 has a holding plate 31, side walls 32, 33, and 34, and a weight 35. The rotating structure 30 is shaped like a box having a cubic opening 39 that opens in the positive direction of the Z axis. The holding plate 31 corresponds to the bottom plate of the opening 39, and the side walls 32, 33, and 34 and weight 35 correspond to the side plates of the opening 39. The side walls 32, 33, and 34 and weight 35 surround the first detection structure 10 and the second detection structure 20 with a gap therebetween in the ZX plane direction.

[0034] The holding plate 31, side walls 32, 33, 34, and weight 35 constituting the rotating structure 30 are integrally formed of, for example, the same material. The rotating structure 30 is formed of, for example, a single crystal of a p-type silicon (Si) semiconductor. The rotating structure 30 may contain boron (B) or aluminum (Al) as a p-type dopant. The resistance value of silicon (Si) used in the rotating structure 30 is, for example, about 10 mΩ·cm. The material of the rotating structure 30 is not limited to p-type single crystal silicon as long as it can generate an electrostatic force between the control electrode. The material of the rotating structure 30 may be, for example, n-type single crystal silicon, p-type or n-type polycrystalline silicon, a semiconductor other than silicon, or a composite structure in which a semiconductor or metal is formed on the surface of an insulator.

[0035] The holding plate 31 is provided between the first detection structure 10 and the substrate 60 in the Z-axis direction, and between the second detection structure 20 and the substrate 60 in the Z-axis direction. The holding plate 31 is provided at a distance from the first detection structure 10, the second detection structure 20, and the substrate 60. A through hole 31H is formed in the holding plate 31, penetrating in the Z-axis direction. The first support 10P, the second support 20P, and the support part 50 are inserted into the through hole 31H.

[0036] The side walls 32, 33, 34 and the weight 35 extend from the outer edge of the holding plate 31 toward the positive Z-axis direction. The side wall 32 is provided on the negative Y-axis side of the detection structure 100. The side wall 33 is provided on the positive Y-axis side of the detection structure 100. The side wall 34 is provided on the negative X-axis side of the detection structure 100. The weight 35 is provided on the positive X-axis side of the detection structure 100. The side wall 32 connects the ends of the side wall 34 and the weight 35 on the negative Y-axis side. The side wall 33 connects the ends of the side wall 34 and the weight 35 on the positive Y-axis side. The inner surfaces of the side walls 32 and 33 are connected to the translation structure 40, which holds the entire rotation structure 30.

[0037] The weight 35 generates mass asymmetry in the rotating structure 30. Specifically, the mass of the weight 35 is larger than the mass of the side wall 34. As a result, the mass of the rotating structure 30 on the negative X-axis side of the rotation center D is asymmetric with the mass of the rotating structure 30 on the positive X-axis side of the rotation center D. The center of gravity C of the weight 35 is located, for example, on the positive Z-axis side of the rotation center D. Since the heights of the rotation center D and the center of gravity C from the substrate 60 are different from each other, when the capacitance type acceleration sensor 1 receives an acceleration translating in the X-axis direction, the rotating structure 30 rotates. The center of gravity C of the weight 35 may be located on the negative Z-axis side of the rotation center D.

[0038] The translation structure 40 translates in the X-axis direction due to the acceleration in the X-axis direction. Specifically, the translation structure 40 connected to the side walls 32 and 33 translates due to being pulled by the weight 35 that translates in the X-axis direction due to the acceleration in the X-axis direction. The translation structure 40 is provided between the first detection structure 10 and the second detection structure 20. The translation structure 40 has a surface 40A provided on the side facing the first detection structure 10 and a surface 40B provided on the side facing the second detection structure 20. The surfaces 40A and 40B correspond to a pair of main surfaces extending along the YZ plane of the translation structure 40. The translation structure 40 is, for example, integrally formed of the same material as the rotation structure 30.

[0039] The support section 50 is connected to the translation structure section 40. The support section 50 supports the translation structure section 40, and supports the rotation structure section 30 via the translation structure section 40. The support section 50 is provided in a quadrangular prism shape extending from the substrate 60 toward the positive side of the Z axis. The support section 50 is inserted into the through hole 31H formed in the holding plate section 31 at a distance from the through hole 31H. The support section 50 is located at the center of the translation structure section 40 in the Y axis direction, and is located between the first support column 10P and the second support column 20P in the X axis direction. The material of the support section 50 is, for example, silicon, and may be integrally formed from the same material as the rotation structure section 30 and the translation structure section 40.

[0040] The substrate 60 has a surface 60A provided on the side facing the rotating structure 30, and a surface 60B on the opposite side to the surface 60A. The surfaces 60A, 60B correspond to a pair of main surfaces of the substrate 60 extending along the XY plane. The first support 10P, the support 50, and the second support 20P are connected to the surface 60A of the substrate 60. The substrate 60 is made of, for example, silicon, and may be integrally formed from, for example, the same material as the base materials 11, 12 and the support 50.

[0041] Next, changes in the capacitance type acceleration sensor 1 when it is subjected to acceleration in the positive direction of the Z axis will be described with reference to Fig. 3 and Fig. 4. Fig. 3 is a plan view showing changes in the capacitance type acceleration sensor when it is subjected to acceleration in the Z axis direction. Fig. 4 is a cross-sectional view showing changes in the capacitance type acceleration sensor when it is subjected to acceleration in the Z axis direction.

[0042] When the capacitance type acceleration sensor 1 receives an acceleration ACC_Z in the positive direction of the Z axis, a force Fz in the positive direction of the Z axis is generated in the weight 35. As shown in FIG. 2, when the distance in the X-axis direction between the rotation center D and the center of gravity C is L, a moment Myz=Fz×L is generated in the weight 35 in the counterclockwise direction. As shown in FIG. 4, in the cross-sectional view, the rotation structure 30 tilts counterclockwise, and the translation structure 40 also tilts counterclockwise. As the translation structure 40 tilts in the cross-sectional view, as shown in FIG. 3, in the plan view, the translation structure 40 bends from the support 50 as a starting point. Since the first detection structure 10 and the second detection structure 20 do not translate or rotate, the distance between the electrode E1L and the translation structure 40 decreases, and the distance between the electrode E1R and the translation structure 40 increases, as shown in FIG. 4. Also, the distance between electrode E2L and translator structure 40 increases, and the distance between electrode E2R and translator structure 40 decreases. 1L =C 1R The capacity was C 1L >C 1R Changes to C 2L =C 2R The capacity was C 2L <C 2R changes to.

[0043] Next, changes in the capacitance-type acceleration sensor 1 when it is subjected to acceleration in the positive direction of the X-axis will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is a plan view showing changes in the capacitance-type acceleration sensor when it is subjected to acceleration in the X-axis direction. Fig. 6 is a cross-sectional view showing changes in the capacitance-type acceleration sensor when it is subjected to acceleration in the X-axis direction.

[0044] When the capacitance type acceleration sensor 1 receives an acceleration ACC_X in the positive direction of the X-axis, a force Fx in the positive direction of the X-axis is generated in the weight 35. As shown in FIG. 2, when the distance in the Z-axis direction between the rotation center D and the center of gravity C is H, a clockwise moment Myx=Fx×H is generated in the weight 35. As shown in FIG. 6, in a cross-sectional view, the rotation structure 30 tilts clockwise, and the translation structure 40 also tilts clockwise. As the translation structure 40 tilts in a cross-sectional view, the translation structure 40 bends from the support 50 in a plan view, as shown in FIG. 5. The translation structure 40 not only rotates, but also translates in the positive direction of the X-axis. In this case, the first detection structure 10 and the second detection structure 20 do not translate or rotate, so that, as shown in FIG. 6, regardless of the magnitude relationship between the rotational displacement and the translational displacement of the translational structure 40, the distance between the electrode E1L and the translational structure 40 increases, and the distance between the electrode E1R and the translational structure 40 decreases. In other words, C 1L =C 1R The capacity was C 1L <C 1R Also, if the rotational displacement of the translation structure 40 is larger than the translational displacement, the distance between the electrode E2L and the translation structure 40 decreases, and the distance between the electrode E2R and the translation structure 40 increases. 2L =C 2R The capacity was C 2L >C 2R If the rotational displacement of the translator structure 40 is smaller than the translational displacement, the distance between the electrode E2L and the translator structure 40 increases and the distance between the electrode E2R and the translator structure 40 decreases. 2L =C 2R The capacity was C 2L <C 2R changes to.

[0045] Next, with reference to FIGS. 7 to 9, a method of servo control will be described. FIG. 7 is a cross-sectional view showing changes in the translational structure when receiving accelerations in the X-axis direction and the Z-axis direction. FIG. 8 is a diagram showing a part of the servo control in the first embodiment. FIG. 9 is a diagram showing a part of the servo control in the first embodiment. FIGS. 7 to 9 are diagrams for explaining a method of calculating the acceleration ACC_Z when the capacitance type acceleration sensor 1 receives both the acceleration ACC_Z in the positive Z-axis direction and the acceleration ACC_X in the positive X-axis direction.

[0046] As shown in FIG. 7, let the translational displacement of the translational structure 40 in the positive X-axis direction be u, the rotational displacement in the clockwise direction be θ, the electrode areas of the electrodes E1L, E2L, E1R, and E2R be S, the initial distances between the electrodes E1L, E2L, E1R, and E2R and the translational structure 40 be d, and the permittivity of vacuum be ε0. Let the dimension along the Y-axis from the initial center position of the translational structure 40 to the upper end on the positive Y-axis side of the electrode E1L, the dimension along the Y-axis from the initial center position of the translational structure 40 to the upper end on the positive Y-axis side of the electrode E2L, the dimension along the Y-axis from the initial center position of the translational structure 40 to the lower end on the negative Y-axis side of the electrode E1R, and the dimension along the Y-axis from the initial center position of the translational structure 40 to the lower end on the negative Y-axis side of the electrode E2R be h.

[0047] When the difference between the distance between the upper end of each of the electrodes E1L, E2L, E1R, and E2R and the translational structure 40 and the distance between the lower end and the translational structure 40 due to the rotational displacement θ of the translational structure 40 is δ, and since δ << d, the capacitance C 1L ,C 1R ,C 2L ,C 2R is calculated by the following formula.

Equation

[0048] Based on the above formula 1, the capacitance C 1L ,C 1R ,C 2L ,C 2R is expressed by the following formula.

number

number

number

number

[0049] C sum =(C 1R -C 1L )+(C 2R -C 2L ), then C sum is expressed by the following formula:

number

[0050] The constant ε0 and the design values ​​S and d are constants. Therefore, C sum is a function with u as a variable. u is determined by ACC_X and does not depend on ACC_Z, so C sum is a function f of the translational displacement u of the rotation and translational displacement of the translation structure unit 40 caused by ACC_X. Xu Defined as (ACC_X).

[0051] C Diff =(C 1R -C 2R )-(C 1L -C 2L ), then C Diff is expressed by the following formula:

number

[0052] θ ACC _ X is the rotation angle of the translation structure 40 due to the acceleration ACC_X, and θ ACC _ Zis the rotation angle of the translation structure 40 caused by the acceleration ACC_Z. The constant ε0 and the design values ​​S, h, and d are constants. Therefore, C Diff The first term of is θ ACC _ Z Function f Z θ(ACC_Z). Also, C Diff The second term of α(u,θ) is the ratio of the translational and rotational displacements caused by ACC_X. ACC _ X ) and the function f of the translational displacement u caused by ACC_X Xu It is defined as a multiplier of (ACC_X). ACC _ X ), f Xu (ACC_X) and f Z θ(ACC_Z) is determined by design.

[0053] First, as shown in Figure 8, sum ACC_X is detected from the change in θ and an electrostatic attractive force is generated to perform force feedback so that u becomes 0 (S10). Next, as shown in FIG. ACC _ X Force feedback is performed so that u becomes 0 (S20). At this time, the change in α(u,θ ACC _ X ) times the change caused by ACC_X. Finally, the remaining θ ACC _ Z Detect ACC_Z from θ ACC _ Z Force feedback is performed so that becomes 0 (S30).

[0054] Here, α(u,θ ACC _ X) is determined by the device structure and is not affected by variations in the width of the translational structure 40, making it possible to simplify calibration. By setting the product of the displacement detector and the coefficient of force feedback when performing force feedback to be sufficiently larger than the spring constant of the translational structure 40, it is possible to make the sensitivity of the capacitance type acceleration sensor 1 independent of the spring constant of the translational structure 40. This makes the sensitivity of the capacitance type acceleration sensor 1 less susceptible to variations in the processing dimensions and processing positions during the manufacturing process. In addition, the sensitivity of the capacitance type acceleration sensor 1 can be electrically set, and θ ACC _ Z The measurement range can be expanded.

[0055] In this embodiment, the effects of translational and rotational displacements caused by ACC_Z are removed by feedback control, and θ ACC _ Z However, the method of detecting ACC_Z is not limited to this. For example, ACC_Z may be calculated using Equation 6 and Equation 7.

[0056] As described above, according to this embodiment, the detection structure 100 has electrodes E1L and E2L arranged opposite to surface 40A of the translation structure 40 and aligned in the Z-axis direction, and electrodes E1R and E2R arranged opposite to surface 40B of the translation structure 40 and aligned in the Z-axis direction. Electrodes E1L and E1R are arranged opposite to each other in the X-axis direction with the translation structure 40 in between, and electrodes E2L and E2R are arranged opposite to each other in the X-axis direction with the translation structure 40 in between.

[0057] According to this, the capacitance C of the electrodes E1L, E2L, E1R, and E2R 1L ,C 1R ,C 2L ,C 2R By measuring the acceleration in the X-axis direction, it is possible to improve the calculation accuracy of the rotational displacement of the translation structure unit 40 caused by the acceleration in the Z-axis direction by excluding the acceleration in the X-axis direction. Therefore, it is possible to improve the detection accuracy of the acceleration in the Z-axis direction.

[0058] In this embodiment, the capacitance type acceleration sensor 1 detects capacitance C 1L ,C 1R ,C 2L ,C 2R Based on this, an electrostatic force is generated to counter the rotation and translation of the translation structure 40, thereby performing servo control.

[0059] According to this, α(u,θ ACC _ X ) is determined by the device structure and is not affected by dimensional variations in the translational structure 40, making it possible to simplify calibration. By setting the product of the displacement detector and the force feedback coefficient when performing force feedback to be sufficiently larger than the spring constant of the translational structure 40, it is possible to make the sensitivity of the capacitance type acceleration sensor 1 independent of the spring constant of the translational structure 40. This makes the sensitivity of the capacitance type acceleration sensor 1 less susceptible to variations in the processing dimensions and processing positions during the manufacturing process. In addition, the sensitivity of the capacitance type acceleration sensor 1 can be electrically set, and θ ACC _ Z The measurement range can be expanded.

[0060] Other embodiments will be described below. Note that the same or similar components as those in the first embodiment are denoted by the same or similar reference numerals, and the description thereof will be omitted as appropriate. Also, similar effects due to similar components will not be mentioned one by one.

[0061] <Second embodiment> Next, the configuration of a capacitance-type acceleration sensor 2 according to a second embodiment will be described with reference to Fig. 10 and Fig. 11. Fig. 10 is a plan view of the capacitance-type acceleration sensor according to the second embodiment. Fig. 11 is a cross-sectional view of the capacitance-type acceleration sensor according to the second embodiment.

[0062] The capacitance type acceleration sensor 2 includes electrodes E31, E32, E41, and E42 instead of the electrodes E11, E12, E21, and E22. The electrodes E31 and E32 correspond to an example of a third control electrode that generates an electrostatic force for servo control. The electrodes E41 and E42 correspond to an example of a fourth control electrode that generates an electrostatic force for servo control.

[0063] The electrodes E31 and E32 are disposed on a surface 11C of the first detection structure 10 facing the holding plate 31. The electrodes E31 and E32 are disposed in a strip shape on the surface 11C of the base material 11 of the first detection structure 10 from the end on the surface 11E side to the end on the surface 11F side. The electrodes E31 and E32 are disposed side by side in the X-axis direction, and the electrode E31 is located on the X-axis positive side of the electrode E32. The electrodes E41 and E42 are disposed on a surface 21C of the second detection structure 20 facing the holding plate 31. The electrodes E41 and E42 are disposed in a strip shape on the surface 21C of the base material 21 of the second detection structure 20 from the end on the surface 21E side to the end on the surface 21F side. The electrodes E41 and E42 are disposed side by side in the X-axis direction, and the electrode E41 is located on the X-axis negative side of the electrode E42.

[0064] According to this, even if the dimension in the Z-axis direction of the capacitance type acceleration sensor 2 is small, the areas of the third control electrode and the fourth control electrode can be increased, and a large electrostatic force can be generated, thereby improving the efficiency of the servo control of the capacitance type acceleration sensor 2.

[0065] The number and shape of the third control electrodes are not limited to those described above. For example, the third control electrode may consist of one electrode. The third control electrode may have three or more electrodes arranged in the X-axis direction, or may have electrodes arranged in the Y-axis direction. The same applies to the fourth control electrode.

[0066] <Third embodiment> Next, the configuration of a capacitance-type acceleration sensor 3 according to a third embodiment will be described with reference to Fig. 12 and Fig. 13. Fig. 12 is a plan view of the capacitance-type acceleration sensor according to the third embodiment. Fig. 13 is a cross-sectional view of the capacitance-type acceleration sensor according to the third embodiment.

[0067] The capacitance type acceleration sensor 3 includes electrodes E51, E52, E53, and E54 instead of the electrodes E11, E12, E21, and E22. The electrodes E51, E52, E53, and E54 correspond to an example of a fifth control electrode that generates an electrostatic force for servo control.

[0068] The electrodes E51, E52, E53, and E54 are provided on the surface 60A of the substrate 60 facing the holding plate 31. In a plan view, the electrodes E51 and E52 are provided in a strip shape from a region overlapping the surface 11E of the base material 11 of the first detection structure 10 to a region overlapping the surface 11F. The electrodes E51 and E52 are provided side by side in the X-axis direction, and the electrode E51 is located on the X-axis positive side of the electrode E52. In a plan view, the electrodes E53 and E54 are provided in a strip shape from a region overlapping the surface 21E of the base material 21 of the second detection structure 20 to a region overlapping the surface 21F. The electrodes E53 and E54 are provided side by side in the X-axis direction, and the electrode E53 is located on the X-axis negative side of the electrode E54.

[0069] According to this, since the area of ​​the fifth electrode is not restricted by the area of ​​the base materials 11 and 21 of the detection structures 10 and 20, the area of ​​the fifth electrode can be increased, and a large electrostatic force can be generated. Therefore, the efficiency of the servo control of the capacitance type acceleration sensor 2 can be improved.

[0070] The number and shape of the fifth control electrodes are not limited to the above. For example, the fifth control electrode may have only one electrode overlapping the first detection structure in a plan view, and the fifth control electrode may have only one electrode overlapping the second detection structure in a plan view. The fifth control electrode may have only three electrodes aligned in the X-axis direction, or may have five or more electrodes. The fifth control electrode may also have electrodes aligned in the Y-axis direction.

[0071] <Fourth embodiment> Next, the configuration of a capacitance-type acceleration sensor 4 according to a fourth embodiment will be described with reference to Fig. 14 and Fig. 15. Fig. 14 is a plan view of the capacitance-type acceleration sensor according to the fourth embodiment. Fig. 15 is a cross-sectional view of the capacitance-type acceleration sensor according to the fourth embodiment.

[0072] The capacitance type acceleration sensor 4 includes electrodes E61, E62, E63, and E64 instead of the electrodes E11, E12, E21, and E22. The electrodes E61, E62, E63, and E64 correspond to an example of a sixth control electrode that generates an electrostatic force for servo control.

[0073] The capacitance type acceleration sensor 4 further includes a cover 70. The cover 70 is joined to the substrate 60 and seals the first detection structure 10, the second detection structure 20, the rotation structure 30, and the translation structure 40. The cover 70 includes a top wall 71 facing the substrate 60 in the Z-axis direction, and side walls 72, 73, 74, and 75 extending from the outer edge of the top wall 71 toward the substrate 60. The side wall 72 extends from the outer edge extending along the Y-axis direction on the X-axis negative side of the top wall 71. The side wall 73 extends from the outer edge extending along the Y-axis direction on the X-axis positive side of the top wall 71. The side wall 74 extends from the outer edge extending along the X-axis direction on the Y-axis negative side of the top wall 71. The side wall portion 75 extends from an outer edge portion of the top wall portion 71 on the Y-axis positive side, the outer edge portion extending along the X-axis direction.

[0074] The electrodes E61 and E62 are provided on the inner surface of the side wall portion 72 of the cover 70, i.e., the surface facing the side wall portion 34 of the rotating structure 30. The electrodes E61 and E62 are provided in a strip shape from the portion of the side wall portion 72 connected to the side wall portion 74 to the portion connected to the side wall portion 75. The electrodes E61 and E62 are provided side by side in the Z-axis direction, and the electrode E61 is located on the Z-axis positive side of the electrode E62. The electrodes E63 and E64 are provided on the inner surface of the side wall portion 73 of the cover 70, i.e., the surface facing the weight portion 35 of the rotating structure 30. The electrodes E63 and E64 are provided in a strip shape from the portion of the side wall portion 73 connected to the side wall portion 74 to the portion connected to the side wall portion 75. The electrodes E63 and E64 are provided side by side in the Z-axis direction, and the electrode E63 is located on the Z-axis positive side of the electrode E64.

[0075] This makes it possible to perform servo control while sealing the first detection structure 10, the second detection structure 20, the rotation structure 30, and the translation structure 40.

[0076] The number and shape of the sixth control electrodes are not limited to the above. For example, the sixth control electrode may have one electrode arranged to face the side wall of the rotating structure, and may have one electrode arranged to face the weight of the rotating structure. The sixth control electrode may have three or more electrodes arranged to face the side wall of the rotating structure and aligned in the Z-axis direction, or may have an electrode arranged to face the side wall of the rotating structure and aligned in the Y-axis direction. The same applies to the electrode of the sixth control electrode arranged to face the weight of the rotating structure. The sixth control electrode may be provided on at least one inner surface of the top wall 71 and the side wall portions 74 and 75.

[0077] The capacitance-type acceleration sensor may be servo-controlled by combining at least two types of control electrodes among the first to sixth control electrodes. The capacitance-type acceleration sensor may be servo-controlled by using at least one electrode of a first electrode group including electrodes E1L and E2L and a second electrode group including electrodes E1R and E2R.

[0078] Some or all of the embodiments of the present invention will be described below. Note that the present invention is not limited to the following descriptions.

[0079] <1> A capacitance-type acceleration sensor for detecting acceleration in a sensitivity axis direction, a rotation structure that rotates around a rotation center due to acceleration in a sensitivity axis direction; a translation structure that translates in a cross axis direction by an acceleration in the cross axis direction that crosses the sensitivity axis direction; a detection structure for detecting capacitance generated between the detection structure and the translation structure; Equipped with The rotating structure has a weight portion that generates mass asymmetry, the plummet is aligned with the translation structure in the cross-axis direction; the translation structure has a first surface opposite to the side on which the weight portion is disposed and a second surface opposite to the first surface; the detection structure includes a first electrode group arranged opposite a first surface of the translation structure and a second electrode group arranged opposite a second surface of the translation structure; The first electrode group includes a first electrode and a second electrode aligned in the sensitivity axis direction, the second electrode group includes a first electrode and a second electrode aligned in the sensitivity axis direction; a first electrode of the first electrode group and a first electrode of the second electrode group are disposed opposite each other with a translation structure therebetween along the intersecting axis direction on one side of the rotation center in the sensitivity axis direction; a second electrode of the first electrode group and a second electrode of the second electrode group are disposed opposite to each other with the translation structure therebetween along the intersecting axis direction, on the other side of the sensitivity axis direction from the rotation center; Capacitive acceleration sensor.

[0080] <2> and servo-controlling the translation structure by generating an electrostatic force that counteracts the rotation and translation of the translation structure based on the capacitance detected in the first electrode group and the second electrode group. <1> The electrostatic capacitance type acceleration sensor according to claim 1 .

[0081] <3> The detection structure includes: a first detection structure provided on the opposite side of the translation structure from the weight portion in the intersecting axis direction; a second detection structure provided on the weight portion side of the translation structure in the intersecting axis direction; having the first detection structure, the translation structure, the second detection structure, and the weight are arranged in this order in the intersecting axis direction; the first electrode group is provided on a surface of the first detection structure facing the first surface of the translation structure, The second electrode group is provided on a surface of the second detection structure facing the second surface of the translation structure. <1> or <2> The electrostatic capacitance type acceleration sensor according to claim 1 .

[0082] <4> a first control electrode and a second control electrode for generating an electrostatic force for servo control; the first control electrode is disposed on a surface of the first detection structure opposite to a surface facing the first surface of the translation structure; the second control electrode is disposed on a surface of the second detection structure opposite to a surface facing the second surface of the translation structure, Each of the first control electrode and the second control electrode includes at least one electrode. <3> The electrostatic capacitance type acceleration sensor according to claim 1 .

[0083] <5> a third control electrode and a fourth control electrode for generating an electrostatic force for servo control; The rotating structure further includes a holding plate portion that holds the weight portion, The retaining plate is connected to the translation structure, the third control electrode is disposed on a surface of the first detection structure facing the holding plate; the fourth control electrode is disposed on a surface of the second detection structure facing the holding plate; Each of the third control electrode and the fourth control electrode includes at least one electrode. <3> or <4> The electrostatic capacitance type acceleration sensor according to claim 1 .

[0084] <6> A support portion that supports the translation structure; a substrate to which the support, the first detection structure, and the second detection structure are connected; a fifth control electrode for generating an electrostatic force for servo control; Further equipped with The rotating structure further includes a holding plate portion that holds the weight portion, The retaining plate is connected to the translation structure, the fifth control electrode is disposed on a surface of the substrate facing the holding plate portion, The fifth control electrode includes at least one electrode, <3> from <5> 13. The electrostatic capacitance type acceleration sensor according to claim 12,

[0085] <7> a cover surrounding the rotation structure, the translation structure, the first detection structure, and the second detection structure; a sixth control electrode for generating an electrostatic force for servo control; Further equipped with The sixth control electrode is disposed on a surface of the cover facing the rotating structure, The sixth control electrode includes at least one electrode, <3> from <6> 13. The electrostatic capacitance type acceleration sensor according to claim 12,

[0086] <8> At least one electrode of the first electrode group and at least one electrode of the second electrode group generate an electrostatic force for servo control. <1> from <7> 13. The electrostatic capacitance type acceleration sensor according to claim 12,

[0087] As described above, according to one aspect of the present invention, it is possible to provide a capacitive acceleration sensor capable of improving detection accuracy.

[0088] The above-described embodiments are provided to facilitate understanding of the present invention, and are not intended to limit the present invention. The present invention may be modified / improved without departing from the spirit thereof, and equivalents are also included in the present invention. In other words, the embodiment and / or modification may be modified by a person skilled in the art as long as it has the characteristics of the present invention. For example, the elements and their arrangements, materials, conditions, shapes, sizes, etc. of the embodiment and / or modification are not limited to those shown as examples, and may be modified as appropriate. In addition, the embodiment and modification are illustrative, and it goes without saying that partial replacement or combination of the configurations shown in different embodiments and / or modifications is possible, and these are also included in the scope of the present invention as long as they include the characteristics of the present invention. [Explanation of symbols]

[0089] 1...Capacitive acceleration sensor 100...detection structure 10...First detection structure 11...Base material of first detection structure 20...Second detection structure 21...Substrate of second detection structure 30...Rotating structure 31...Holding plate part 32, 33, 34...Side wall 35... Weight part 40…Translation structure part 50...Support part 60...Substrate E1L: First electrode of the first electrode group E2L: Second electrode of the first electrode group E1R: 1st electrode of the 2nd electrode group E2R: Second electrode of the second electrode group E11, E12: First control electrode E21, E22: Second control electrode D…Center of rotation C...center of gravity

Claims

1. A capacitance-type acceleration sensor for detecting acceleration in a sensitivity axis direction, a rotation structure that rotates around a rotation center due to acceleration in the sensitivity axis direction; a translation structure that translates in a cross-axis direction intersecting the sensitivity axis direction due to an acceleration in the cross-axis direction; a detection structure for detecting capacitance generated between the detection structure and the translation structure; Equipped with the rotating structure has a weight portion that generates mass asymmetry, the weight portion is aligned with the translation structure in the cross-axis direction; the translation structure has a first surface opposite to a side on which the weight portion is disposed and a second surface opposite to the first surface, the detection structure includes a first electrode group arranged opposite the first surface of the translation structure and a second electrode group arranged opposite the second surface of the translation structure; the first electrode group includes a first electrode and a second electrode aligned in the sensitivity axis direction, the second electrode group includes a first electrode and a second electrode aligned in the sensitivity axis direction, the first electrode of the first electrode group and the first electrode of the second electrode group are disposed opposite to each other with the translation structure therebetween along the intersecting axis direction, on one side of the sensitivity axis direction relative to the rotation center; the second electrode of the first electrode group and the second electrode of the second electrode group are disposed opposite to each other with the translation structure therebetween along the intersecting axis direction, on the other side of the sensitivity axis direction relative to the rotation center; Capacitive acceleration sensor.

2. a servo control is performed by generating an electrostatic force that cancels the rotation and translation of the translation structure based on the electrostatic capacitance detected in the first electrode group and the second electrode group; 2. The capacitance type acceleration sensor according to claim 1.

3. The detection structure includes: a first detection structure provided on an opposite side of the translation structure from the weight portion in the intersecting axis direction; a second detection structure provided on the weight portion side of the translation structure in the intersecting axis direction; having the first detection structure, the translation structure, the second detection structure, and the weight portion are arranged in this order in the intersecting axis direction, the first electrode group is provided on a surface of the first detection structure that faces the first surface of the translation structure, the second electrode group is provided on a surface of the second detection structure that faces the second surface of the translation structure; 2. The capacitance type acceleration sensor according to claim 1.

4. a first control electrode and a second control electrode for generating an electrostatic force for servo control; the first control electrode is disposed on a surface of the first detection structure opposite to a surface facing the first surface of the translation structure, the second control electrode is disposed on a surface of the second detection structure opposite to a surface facing the second surface of the translation structure, Each of the first control electrode and the second control electrode includes at least one electrode.

4. The electrostatic capacitance type acceleration sensor according to claim 3.

5. a third control electrode and a fourth control electrode for generating an electrostatic force for servo control; The rotating structure further includes a holding plate portion that holds the weight portion, The holding plate is connected to the translation structure, the third control electrode is disposed on a surface of the first detection structure facing the holding plate portion, the fourth control electrode is disposed on a surface of the second detection structure facing the holding plate portion, Each of the third control electrode and the fourth control electrode includes at least one electrode.

4. The electrostatic capacitance type acceleration sensor according to claim 3.

6. A support portion that supports the translation structure; a substrate to which the support portion, the first detection structure portion, and the second detection structure portion are connected; a fifth control electrode for generating an electrostatic force for servo control; Further equipped with The rotating structure further includes a holding plate portion that holds the weight portion, The holding plate is connected to the translation structure, the fifth control electrode is disposed on a surface of the substrate facing the holding plate portion, The fifth control electrode includes at least one electrode.

4. The electrostatic capacitance type acceleration sensor according to claim 3.

7. a cover surrounding the rotation structure, the translation structure, the first detection structure, and the second detection structure; a sixth control electrode for generating an electrostatic force for servo control; Further equipped with the sixth control electrode is disposed on a surface of the cover facing the rotation structure; The sixth control electrode includes at least one electrode.

4. The electrostatic capacitance type acceleration sensor according to claim 3.

8. At least one electrode of the first electrode group and at least one electrode of the second electrode group generate an electrostatic force for servo control.

2. The capacitance type acceleration sensor according to claim 1.

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