WO2009119470A1 - Angular velocity sensor - Google Patents

Abstract

It is possible to provide an angular velocity sensor which can suppress leak oscillation and appropriately improve the angular velocity detection accuracy. The angular velocity sensor includes: a pair of support beams (16, 17) arranged to oppose each other in the Y-axis direction when the X-axis direction is the longitudinal direction; anchors (22, 23) for fixing and supporting the center positions of the respective support beams; a pair of mass units (10, 11) arranged to oppose to each other between the support beams in the X-axis direction; springs (32-35) connecting the respective mass units to the support beams; an excitation unit for exciting the mass units; and a detection unit for detecting a displacement amount of the support beams displaced when the mass units are oscillated by the Coriolis force. If an angular velocity is generated around the Z-axis when the pair of the mass units (10, 11) is excited with the inverse phase in the X-axis direction by the excitation unit, the Coriolis force is generated in the Y-axis direction and the pair of mass units vibrates with the inverse phase in the Y-axis direction, which seesaw-oscillates the support beams against the anchors as fulcra in the Y-axis direction.

Description

Angular velocity sensor

The present invention relates to an angular velocity sensor formed by using a MEMS (Micro Electro Mechanical System) technology.

The following patent document discloses the structure of an angular velocity sensor formed using MEMS technology.

The angular velocity sensor disclosed in the following Patent Document 1 includes a plurality of mass parts (Mass), and has a structure in which mass parts located at the center and mass parts located on both sides thereof are excited in opposite directions. The center mass is displaced by Coriolis force. A movable-side vibrating electrode constituting the detection electrode and the vibration generating unit is integrally formed in the central mass unit.

In the angular velocity sensor described in Patent Document 2, two mass parts are excited in opposite phases. The mass part is also integrally formed with a movable vibration electrode that constitutes a vibration generating part together with the detection electrode.

Further, the angular velocity sensor disclosed in Patent Document 3 has a structure in which a circular mass portion is excited by a comb-like electrode, and a second mass portion provided in the notch portion is displaced by receiving Coriolis force. The circular mass is supported on the substrate at the center.

Moreover, the angular velocity sensor disclosed in Patent Document 4 includes mass parts on the inner side and the outer side, respectively. In Patent Document 4, the outer mass part is vibrated, the Coriolis force is transmitted from the outer mass part to the inner mass part, and the displacement amount received by the Coriolis force at the inner mass part is measured. .
JP 2002-81939 A WO2006 / 009578 JP 2006-153798 A JP-T-2001-520385

In the inventions described in Patent Documents 1 and 2 described above, both the detection electrode and the movable vibration electrode are integrally formed in the mass portion.

Therefore, the drive signal supplied to the movable-side vibration electrode is likely to leak to the detection side via a parasitic capacitance such as a substrate, and vibration (leakage vibration) in the detection direction occurs in the mass part even when the angular velocity Ω is not acting. It was easy to occur. In order to suppress such leakage vibration, it is necessary to devise such as providing a leakage vibration suppression electrode (quadrature cancellation (balancing) electrode) as in Patent Document 2, for example, and the structure is complicated and large. It was easy to convert.

Further, in Patent Document 3 and Patent Document 4, the movable-side vibration electrode is not directly provided in the mass portion including the detection electrode, and the movable-side vibration electrode is integrated with another mass portion connected to the mass portion including the detection electrode. However, the structure is complicated and the leakage of the drive signal supplied to the vibration generator to the detection side cannot be made sufficiently small. In addition, the configuration that gives rotational vibration as in the angular velocity sensor of Patent Document 3 is more difficult and less feasible than linear vibration, and the vibration direction of the mass portion and the design vibration direction when rotating and vibrating. It is considered that a gap is likely to occur between them, and there is a fear that vibration in an unnecessary direction increases.

In Patent Document 4, the Coriolis force is transmitted from the outer mass portion to the inner mass portion, but with such a configuration, the Coriolis force is greatly attenuated and it is considered difficult to detect with high accuracy.

Therefore, with the structure of the angular velocity sensor described in the above-mentioned patent document, the detection accuracy of the angular velocity cannot be improved appropriately.

Therefore, the present invention is intended to solve the above-described conventional problems, and in particular, an object of the present invention is to provide an angular velocity sensor capable of suppressing leakage vibration and appropriately improving angular velocity detection accuracy.

The angular velocity sensor according to the present invention is disposed so as to face the Y-axis direction with the X-axis direction as the longitudinal direction when the two directions orthogonal to the support substrate and the plane of the support substrate are the X-axis direction and the Y-axis direction. A pair of support beams, an anchor portion for fixing and supporting a substantially central position of each support beam on the support substrate, and a pair of masses disposed between the pair of support beams and facing each other in the X-axis direction Part, a spring part connecting each mass part and each support beam, an excitation part for exciting the mass part, and displacement of the support beam that is displaced by vibration of the mass part under Coriolis force A detection unit for detecting the amount,
When an angular velocity is generated around the Z-axis orthogonal to the X-axis direction and the Y-axis direction in a state where the pair of mass parts are excited in the X-axis direction in the opposite phase by the excitation unit, When the Coriolis force is generated and the pair of mass portions vibrate in the opposite phase in the Y-axis direction, the pair of support beams vibrate in the Y-axis direction with the anchor portion as a fulcrum. It is.

In the present invention, the support beam and the mass portion are connected via the spring portion, and a detection unit for detecting the displacement amount of the support beam is provided. In the present invention, when an angular velocity is applied with the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction as the rotation axis, the mass portion excited in the opposite phase in the X-axis direction receives Coriolis force in the Y-axis direction and vibrates. To do. At this time, the pair of mass portions vibrate in the opposite phase in the Y-axis direction, and the support beam connected via the mass portion and the spring portion vibrates in the Y-axis direction with the anchor portion serving as a fulcrum. According to the configuration of the present invention, it is possible to appropriately suppress the occurrence of leakage vibration and improve the detection accuracy of angular velocity with a simple structure.

In the present invention, the excitation unit is a comb-like fixed-side excitation electrode fixedly supported on the support substrate, and a comb-like movable unit positioned above the support substrate and provided integrally with the mass unit. Preferably, a side excitation electrode is provided, and the movable side excitation electrode vibrates in the X-axis direction by a Coulomb force generated between the fixed side excitation electrode and the movable side excitation electrode. As a result, the pair of mass parts can be excited in the X-axis direction in opposite phases with a simple configuration.

According to the present invention, the detection unit includes a comb-like fixed-side detection electrode fixedly supported on the support substrate, and a comb-teeth-shaped detection electrode positioned above the support substrate and provided integrally with the support beam. Preferably, a movable detection electrode is provided, and a displacement amount of the support beam when the support beam is subjected to seesaw vibration is detected based on a change in capacitance between the movable detection electrode and the fixed detection electrode. Accordingly, the displacement amount of the support beam can be detected with a simple configuration, and the angular velocity detection accuracy can be improved.

In the present invention, it is preferable that the detection unit is provided on both sides of the anchor portion of each support beam in the X-axis direction. As a result, a differential output can be obtained with a simple configuration, and the angular velocity can be detected with high accuracy.

In the present invention, it is preferable that at least a part of the detection unit is located outside the connection point of the support beam with the mass unit in the X-axis direction.

Further, it is more preferable that the entire detection unit is located outside the connection point in the X-axis direction. Thereby, the displacement amount of a support beam can be enlarged and the detection accuracy of angular velocity can be improved more effectively.

In the present invention, it is preferable that the spring portion has a function of absorbing vibration of the mass portion in the X-axis direction and transmitting vibration of the mass portion in the Y-axis direction to the support beam.

In the present invention, the mass portion and the support beam are provided with arm portions extending in directions approaching each other,
The spring portion includes a first spring portion extending in the Y-axis direction, and a second spring portion and a third spring portion extending in opposite directions of the X-axis direction at both ends of the first spring portion, and the second spring. One of the first portion and the third spring portion is connected to the arm portion of the mass portion and the other is connected to the arm portion of the support beam, and the length dimension of the first spring portion is the second spring portion and the third spring portion. It is preferable that the length is longer than the length of the spring portion.

As a result, when the pair of mass parts are excited in the X-axis direction in the opposite phase, the vibration is absorbed by the spring part to suppress the vibration of the support beam, while the pair of mass parts receive the Coriolis force and receive the Y-axis. When vibrating in the opposite phase to the direction, the vibration can be appropriately transmitted to the support beam via the spring portion, and the support beam can be effectively vibrated to seesaw. Therefore, the detection accuracy of angular velocity can be improved more effectively.

According to the configuration of the angular velocity sensor of the present invention, the occurrence of leakage vibration can be appropriately suppressed, and the detection accuracy of angular velocity can be improved with a simple structure.

1 is a plan view of an angular velocity sensor according to the first embodiment of the present invention, FIG. 2 is a plan view of the angular velocity sensor according to the second embodiment of the present invention, and FIGS. 3 and 4 are diagrams of the angular velocity sensor according to the present embodiment. FIG. 5 is a conceptual diagram of the operation, FIG. 5 is a cross-sectional view of the angular velocity sensor shown in FIG. 1 cut along the line AA in the height direction and viewed from the arrow direction, and FIG. 6 shows the angular velocity sensor shown in FIG. A sectional view taken along the line BB in the height direction and viewed from the direction of the arrow, FIG. 7 is a plan view of the spring portion used in the present embodiment.

In each figure, the X-axis direction and the Y-axis direction indicate two orthogonal directions in the support substrate plane. The Z-axis direction indicates a height direction (film thickness direction) orthogonal to the X-axis direction and the Y-axis direction.

The angular velocity sensor 1 is formed using an SOI (Silicon on Insulator) substrate 2. As shown in FIG. 2, the SOI substrate 2 is located between a support substrate 3 formed of a silicon substrate, an SOI layer (active layer) 5 formed of a silicon substrate, and the support substrate 3 and the SOI layer 5. For example, it is a laminated structure of an oxide insulating layer (sacrificial layer) 4 made of SiO ₂ .

As shown in FIG. 1, the SOI layer 5 constituting the SOI substrate 2 includes mass parts (Mass) 10 and 11, excitation parts 12 to 15, support beams 16 and 17, detection parts 18 to 21, and spring parts 32 to 35 is formed. In the drawing, lines are drawn at the boundaries between the parts, but these are made easy to see each part. In fact, these parts are all formed by the same SOI layer 5 and are integrated. None of the mass portions 10 and 11 and the support beams 16 and 17 are below the oxide insulating layer 4, and the mass portions 10 and 11 and the support beams 16 and 17 are located above the support substrate 3. The structures of the excitation units 12 to 15 and the detection units 18 to 21 will be described in detail later.

As shown in FIG. 1, the support beams 16 and 17 extend linearly with the X-axis direction as the longitudinal direction, and the pair of support beams 16 and 17 are arranged to face each other with a gap in the Y-axis direction. As shown in FIGS. 1 and 6, the substantially central position in the X-axis direction of the support beams 16 and 17 is fixedly supported on the support substrate 3 via the anchor portions 22 and 23.

As shown in FIG. 1, a pair of mass portions 10 and 11 are disposed opposite to each other between the pair of support beams 16 and 17 in the X-axis direction. As shown in FIG. 1, arms 24 to 27 extending in the direction of the support beams 16 and 17 are provided on the opposing surfaces 10 a, 10 b, 11 a, and 11 b of the mass portions 10 and 11, respectively, with the support beams 16 and 17. Yes. The positions of the arm portions 24 to 27 are equidistant from the center position in the X-axis direction between the mass portions 10 and 11.

As shown in FIG. 1, arms 28 to 31 extending in the directions of the mass portions 10 and 11 are provided on the opposing surfaces 16a and 17a of the support beams 16 and 17 facing the mass portions 10 and 11, respectively. The positions of the arm portions 28 to 31 are equidistant from the anchor portions 22 and 23.

As shown in FIG. 1, between the arm portion 24 of the mass portion 10 and the arm portion 28 of the support beam 16, between the arm portion 25 of the mass portion 10 and the arm portion 29 of the support beam 17, and between the arm portion 11 of the mass portion 11. Spring portions 32 to 35 are interposed between the portion 26 and the arm portion 30 of the support beam 16 and between the arm portion 27 of the mass portion 11 and the arm portion 31 of the support beam 17, respectively. The spring portions 32 to 35 are less rigid than the support beams 16 and 17. The rigidity can be adjusted by width, length, thickness, and the like. For example, the widths of the spring portions 32 to 35 are formed thinner than the support beams 16 and 17 to reduce the rigidity.

The spring portions 32 to 35 are formed in the shape shown in FIG. 7, for example. FIG. 7 representatively shows the shape of the spring portion 32. As shown in FIG. 7, the spring portion 32 includes a first spring portion 32a extending in the Y-axis direction, a second spring portion 32b extending in opposite directions of the X-axis direction from both ends of the first spring portion 32a in the Y-axis direction, and A third spring portion 32c.

As shown in FIG. 7, the length dimension L1 of the first spring portion 32a is longer than the length dimensions L2 and L3 of the second spring portion 32b and the third spring portion 32c. The lengths L2 and L3 of the second spring part 32b and the third spring part 32c are the same. The length dimensions L1 to L3 are defined by the length of the spring portion 32 on the width center line. As a result, the spring portions 32 to 35 are more rigid in the Y-axis direction than in the X-axis direction.

1 has the same shape as the spring portion 32 shown in FIG. On the other hand, the spring portions 33 and 34 shown in FIG. 1 coincide with a line-symmetric shape with the center line of the first spring portion 32a of the spring portion 32 shown in FIG.

The end portion of the second spring portion 32b of the spring portion 32 shown in FIG. 7 is connected to the arm portion 24 of the mass portion 10, and the end portion of the third spring portion 32c is connected to the arm portion 28 of the support beam 16. Yes. Similarly, the spring portions 33, 34, and 35 are connected to the mass portions 10 and 11 and the arm portions of the support beams 16 and 17.

As shown in FIG. 1, a first excitation unit 12 and a second excitation unit 13 are provided on both outer sides of the mass unit 10 facing each other in the X-axis direction. Further, a third excitation unit 14 and a fourth excitation unit 15 are provided on both outer sides of the mass unit 11 facing in the X-axis direction. Here, since the structure of each excitation part is the same, the structure of the 1st excitation part 12 is demonstrated as a representative.

The first excitation unit 12 is a comb-shaped fixed-side excitation electrode 37 and a comb-shaped movable-side excitation electrode that is integrally formed on the outer surface of the mass unit 10 and is alternately arranged with the fixed-side excitation electrode 37. 36.

As shown in FIG. 1, the fixed-side excitation electrode 37 includes a fixed portion 39 fixedly supported on the support substrate 3 via the oxide insulating layer 4 and a space between the fixed portion 39 and the comb-like movable-side excitation electrode 36. And a comb-like electrode 40 extending in the direction. Although not limited, the oxide insulating layer 4 is not present under the comb-like electrode 40 of the fixed side excitation electrode 37, and the comb-like electrode 40 floats above the support substrate 3.

When alternating drive signals having opposite phases are applied to the first excitation unit 12 and the second excitation unit 13, the movable-side excitation electrode 36 and the fixed-side excitation electrode 37 of each excitation unit 12, 13 are interposed between them. Coulomb force acts to exert driving force, and the mass portion 10 is excited in the X-axis direction. Similarly, AC drive signals having opposite phases are applied to the third excitation unit 14 and the fourth excitation unit 15 to excite the mass unit 11 in the X-axis direction. At this time, the mass parts 10 and 11 are excited in the X-axis direction with an opposite phase.

As shown in FIG. 1, a first detection unit 18 is provided on the opposite side (outside) of the support beam 16 from the opposite surface 16 a and on the right side of the anchor portion 22 in the drawing, and on the left side of the anchor portion 22 in the drawing. 2 detector 19 is provided. As shown in FIG. 1, a third detection unit 20 is provided on the opposite side (outer side) of the support surface 17 of the support beam 17 and on the right side of the anchor portion 23 in the figure, and on the left side of the anchor portion 23 in the figure. Is provided with a fourth detector 21. Here, since the configuration of each detection unit is the same, the configuration of the first detection unit 18 will be described as a representative.

As shown in FIG. 1, the first detection unit 18 has a comb-like movable detection electrode 63 formed integrally with the support beam 16 and a comb-teeth shape alternately arranged with the movable detection electrode 63. The fixed side detection electrode 64 is provided.

As shown in FIG. 1, the fixed side detection electrode 64 includes a fixed portion 65 fixedly supported on the support substrate 3 via the oxide insulating layer 4, and a space between the fixed portion 65 and the comb-like movable side detection electrode 63. And a comb-like electrode 66 extending in a straight line. Although not limited, the oxide insulating layer 4 is not present under the comb-like electrode 66 of the fixed-side detection electrode 64, and the comb-like electrode 66 floats above the support substrate 3.

Next, the operation of the angular velocity sensor 1 according to the present embodiment will be described with reference to FIGS.

The mass units 10 and 11 are excited in the opposite phase in the X-axis direction as shown in FIGS. 3 and 4 by the driving force of the excitation units 12 to 15 shown in FIG. 3 shows a state in which excitation is performed in a direction in which the interval between the mass parts 10 and 11 is widened, and FIG. 4 shows a state in which excitation is performed in a direction in which the interval between the mass parts 10 and 11 is narrowed.

At this time, vibration due to excitation of the mass portions 10 and 11 is hardly absorbed by the spring portions 32 to 35 and transmitted to the support beams 16 and 17. In particular, in the present embodiment, the structure of the spring portions 32 to 35 shown in FIG. 1 or FIG. 7 is adopted, so that the second spring of the spring portion 32 that connects the mass portion 10 and the support beam 16 as shown in FIG. When vibration from the direction of the arrow is applied to the portion 32 (showing the excited state of FIG. 3, the third spring portion 32 c is on the side fixed to the support beam 16), the first spring portion 32 a having a long length dimension. 7 is bent in the X-axis direction as indicated by a dotted line in FIG. 7, so that the vibration can be effectively absorbed and the vibration is hardly transmitted to the support beam 16 via the third spring portion 32 c. Similarly, the other spring portions 33 to 35 absorb the vibration caused by the excitation of the mass portions 10 and 11 and suppress the transmission to the support beams 16 and 17.

3 and 4, when the angular velocity Ω is applied to the angular velocity sensor 1 with the Z-axis direction as the rotation axis in the state where the mass parts 10 and 11 are excited in the opposite phase in the X-axis direction, the Coriolis force is received, The mass parts 10 and 11 vibrate in the opposite phase in the Y-axis direction (not shown). When the vibration at this time is transmitted to the support beams 16 and 17 through the spring portions 32 to 35, the support beams 16 and 17 perform seesaw vibration with the anchor portions 22 and 23 as fulcrums (indicated by dotted lines). The transmission of vibration is slightly absorbed by the spring portion due to the bending of the second spring portion 32b and the third spring portion 32c, but the vibration in the Y-axis direction is dominated by the first spring portion 32a that similarly extends in the Y-axis direction. As a transmission means, the vibration is effectively transmitted to the support beams 16 and 17 through the spring portions 32 to 35.

In FIG. 3, the mass part 10 vibrates in the downward direction in the figure, the mass part 11 vibrates in the upward direction in the figure, and the support beams 16 and 17 on the right side of the anchor parts 22 and 23 vibrate in the directions of arrows C and D. On the other hand, the support beams 16 and 17 on the left side of the anchors 22 and 23 are vibrated in the directions of arrows E and F, and the support beams 16 and 17 are seesaw-oscillated with the anchor portions 22 and 23 as fulcrums in the same direction. Indicates the state. On the other hand, in FIG. 4, the mass part 10 vibrates in the upward direction in the figure, the mass part 11 vibrates in the direction shown in the figure, and the support beams 16 and 17 on the right side of the anchor parts 22 and 23 vibrate in the directions of arrows G and H. On the other hand, the support beams 16 and 17 on the left side of the anchor portions 22 and 23 are vibrated in the directions of arrows I and J so that the support beams 16 and 17 are in the same direction and in the opposite direction to FIG. , 23 is used as a fulcrum, and the seesaw is oscillating.

3 and 4, when the support beams 16 and 17 are seesaw-oscillated, the capacitances of the detectors 18 to 21 change based on the displacement of the support beams 16 and 17 in the Y-axis direction. Specifically, as shown in FIG. 3, when the support beams 16 and 17 perform seesaw vibration that moves downward (upward to the right) in the figure, the capacitances of the first detector 18 and the fourth detector 21 shown in FIG. 1 are small. Thus, the capacitances of the second detection unit 19 and the third detection unit 20 are increased. On the other hand, as shown in FIG. 4, when the support beams 16 and 17 perform seesaw vibration that moves upward (downward to the left) in the figure, the capacitances of the first detector 18 and the fourth detector 21 shown in FIG. The capacitances of the second detector 19 and the third detector 20 are reduced. Thereby, the displacement amount of the support beams 16 and 17 can be obtained as a differential output of capacitance change.

As described above, in this embodiment, the support beams 16 and 17 and the mass portions 10 and 11 are connected via the spring portions 32 to 35, and the detection units 18 to 21 that detect the displacement amount of the support beams 16 and 17 are provided. Provided. In the present embodiment, when an angular velocity is applied with the Z-axis direction orthogonal to the X-axis direction and the Y-axis direction as the rotation axis, the mass parts 10 and 11 that have been excited in the opposite phase in the X-axis direction have the Coriolis force in the Y-axis direction. Vibrate in response. At this time, the pair of mass portions 10 and 11 vibrate in opposite phases in the Y-axis direction, and the support beams 16 and 17 connected to the mass portions 10 and 11 via the spring portions 32 to 35 are anchor portions in the Y-axis direction. The seesaw vibrates using 22 and 23 as fulcrums. According to the configuration of the present embodiment, the occurrence of leakage vibration can be appropriately suppressed, and the detection accuracy of the angular velocity Ω can be improved with a simple structure.

In the embodiment shown in FIG. 2, space portions 10d and 11d are formed inside the mass portions 10 and 11, and excitation portions 50 and 51 are formed in the space portions 10d and 11d. The configuration of the excitation units 50 and 51 includes a fixed-side excitation electrode and a movable-side excitation electrode, similarly to the excitation units 12 to 15 shown in FIG. The embodiment of FIG. 2 is the same as FIG. 1 except for the configuration of the excitation unit. If the excitation units 50 and 51 are positioned inside the mass units 10 and 11 as shown in FIG. 2, the angular velocity sensor can be reduced in size.

In addition, it is preferable that at least a part of the detection units 18 to 21 is positioned outside in the X-axis direction from the connection point between the support beams 16 and 17 and the mass units 10 and 11. Here, the “connection point” shown in FIGS. 1 and 2 is the center position of the arm portions 28 to 31 protruding from the support beams 16 and 17 in the direction of the mass portions 10 and 11. Thus, by positioning the detectors 18 to 21 outside the connecting point in the X-axis direction, the displacement of the support beams 16 and 17 that vibrate the seesaw can be increased, and the detection accuracy of the angular velocity Ω is effectively improved. be able to.

Further, if the entire detection units 18 to 21 are positioned outside the connecting point of the support beams 16 and 17 with the mass units 10 and 11 in the X-axis direction, the displacement amount of the support beams is more effectively increased. Thus, the detection accuracy of angular velocity can be improved.

The detection units 18 to 21 may be other than the capacitance type, but the capacitance type can detect the displacement amount of the support beams 16 and 17 with a simple configuration with high accuracy.

The top view of the angular velocity sensor of 1st Embodiment of this invention, The top view of the angular velocity sensor of 2nd Embodiment of this invention, The conceptual diagram of operation | movement of the angular velocity sensor in this embodiment, The conceptual diagram of operation | movement of the angular velocity sensor in this embodiment, 1 is a cross-sectional view when the angular velocity sensor shown in FIG. 1 is cut in the height direction along the line AA and viewed from the arrow direction; FIG. 1 is a cross-sectional view of the angular velocity sensor shown in FIG. 1 taken along the line BB in the height direction and viewed from the arrow direction; The top view of the spring part used for this embodiment,

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Angular velocity sensor 2 SOI substrate 3 Support substrate 4 Oxide insulation layer 5 SOI layer 10, 11 Mass part 12-15, 50, 51 Excitation part 16, 17 Support beam 18-21 Detection part 22, 23 Anchor part 24-31 Arm part 32 to 35 Spring portion 32a First spring portion 32b Second spring portion 32c Third spring portion 36 Movable side excitation electrode 37 Fixed side excitation electrode 63 Movable side detection electrode 64 Fixed side detection electrode

Claims (8)

A support substrate and a pair of support beams arranged opposite to each other in the Y-axis direction, with the X-axis direction being a longitudinal direction when two directions perpendicular to the support substrate plane are defined as an X-axis direction and a Y-axis direction, An anchor portion for fixing and supporting a substantially center position of the support beam on the support substrate, a pair of mass portions disposed between the pair of support beams and facing each other in the X-axis direction, A spring part that connects each support beam, an excitation part for exciting the mass part, and a detection for detecting a displacement amount of the support beam that is displaced when the mass part is vibrated by receiving Coriolis force And
When an angular velocity is generated around the Z-axis orthogonal to the X-axis direction and the Y-axis direction in a state where the pair of mass parts are excited in the X-axis direction in the opposite phase by the excitation unit, An angular velocity, wherein the Coriolis force is generated and the pair of mass portions vibrate in opposite phases in the Y-axis direction, so that the pair of support beams vibrate in the Y-axis direction with the anchor portion as a fulcrum. Sensor. The excitation unit includes a comb-shaped fixed-side excitation electrode fixedly supported on the support substrate, and a comb-shaped movable-side excitation electrode provided above the support substrate and provided integrally with the mass unit. The angular velocity sensor according to claim 1, wherein the movable-side excitation electrode vibrates in the X-axis direction by a Coulomb force generated between the fixed-side excitation electrode and the movable-side excitation electrode. The detection section includes a comb-shaped fixed detection electrode fixedly supported on the support substrate, and a comb-shaped movable detection electrode positioned above the support substrate and provided integrally with the support beam. The angular velocity sensor according to claim 1, wherein a displacement amount of the support beam when the support beam vibrates seesaw is detected based on a capacitance change between the movable detection electrode and the fixed detection electrode. . The angular velocity sensor according to any one of claims 1 to 3, wherein the detection section is provided on each side of the anchor section of each support beam in the X-axis direction. The angular velocity sensor according to any one of claims 1 to 4, wherein at least a part of the detection unit is located on an outer side in the X-axis direction than a connection point with the mass unit of the support beam. The angular velocity sensor according to claim 5, wherein the whole of the detection unit is located outside of the connection point in the X-axis direction. The said spring part has a function which absorbs the vibration to the X-axis direction of the said mass part, and transmits the vibration to the said Y-axis direction of the said mass part to the said support beam. Angular velocity sensor. The mass portion and the support beam are provided with arm portions extending in directions approaching each other,
The spring portion includes a first spring portion extending in the Y-axis direction, and a second spring portion and a third spring portion extending in opposite directions of the X-axis direction at both ends of the first spring portion, and the second spring. One of the first portion and the third spring portion is connected to the arm portion of the mass portion and the other is connected to the arm portion of the support beam, and the length dimension of the first spring portion is the second spring portion and the third spring portion. The angular velocity sensor according to claim 1, wherein the angular velocity sensor is longer than a length dimension of the spring portion.

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