Sensor and electronic apparatus

Abstract

To provide a sensor and an electronic apparatus which are able to obtain stable characteristics.SOLUTION: The sensor comprises a substrate and an element part. The element part includes a first fixed part and a first fixed electrode fixed to the substrate, and a first movable part. The first movable part includes a first movable base part, a first another movable base part, and a first movable structure. The first movable structure includes a first beam, a first movable electrode, and a first connection. The first beam is connected to the first movable base part and the first another movable base part. The first connection connects the first movable electrode to the first beam. The first movable electrode includes a first movable electrode base part, and a plurality of first movable projections connected to the first movable electrode base part. The first fixed electrode includes a first fixed electrode base part, and a plurality of first fixed projections connected to the first fixed electrode base part. The plurality of first movable projections engage with the plurality of first fixed projections in an inter-digital manner.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE INVENTION Embodiments of the present invention relate to sensors and electronic devices. [Background technology]

[0002] For example, there are sensors that use MEMS structures, and stable characteristics are desired for sensors. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-1828 Summary of the Invention [Problem to be solved by the invention]

[0004] The embodiments provide sensors and electronic devices that can achieve stable characteristics. [Means for solving the problem]

[0005] According to an embodiment, the sensor includes a base and an element unit. The element unit includes a first fixed unit fixed to the base, a first fixed electrode fixed to the base, and a first movable unit. A first gap is provided between the base and the first movable unit. The first movable unit includes a first movable base supported by the first fixed unit, a first other movable base connected to the first movable base, and a first movable structure. The first movable structure includes a first beam, a first movable electrode, and a first connecting unit. The first beam includes a first beam unit, a first other beam unit, and a first intermediate beam unit between the first beam unit and the first other beam unit. A second direction from the first beam unit to the first other beam unit intersects with a first direction from the base to the first fixed unit. The first beam unit is connected to the first movable base. The first other beam unit is connected to the first other movable base. A third direction from the first beam to the first movable electrode intersects a plane including the first direction and the second direction. The first connection portion connects the first movable electrode to the first intermediate beam portion. The first movable electrode includes a first movable electrode base and a plurality of first movable protrusions connected to the first movable electrode base and aligned along the second direction. The first fixed electrode includes a first fixed electrode base and a plurality of first fixed protrusions connected to the first fixed electrode base and aligned along the second direction. The plurality of first movable protrusions mesh with the plurality of first fixed protrusions in a comb-teeth shape. The plurality of first movable protrusions include a first movable end protrusion, a first movable other end protrusion, and a plurality of first movable intermediate protrusions. The first movable end protrusion is one end of the plurality of first movable protrusions in the second direction. The first movable other end protrusion is another end of the plurality of first movable protrusions in the second direction. The plurality of first movable intermediate protrusions are located between the first movable end protrusion and the first movable other end protrusion, and the width of the first movable end protrusion along the second direction is the same as the width of the first movable other end protrusion along the second direction. [Brief explanation of the drawings]

[0006] [Figure 1] 1A and 1B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 2] FIG. 2 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 3] 3(a) to 3(c) are schematic cross-sectional views illustrating the sensor according to the first embodiment. [Figure 4] FIG. 4 is a schematic cross-sectional view illustrating the sensor according to the first embodiment. [Figure 5] 5(a) and 5(b) are schematic views illustrating the sensor according to the first embodiment. [Figure 6] FIG. 6 is a graph illustrating the characteristics of the sensor according to the first embodiment. [Figure 7] 7A and 7B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 8] 8A and 8B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 9] 9A and 9B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 10] 10A and 10B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 11] 11A and 11B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 12] 12A and 12B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 13] 13A and 13B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 14] 14A and 14B are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 15] FIG. 15 is a schematic plan view illustrating a part of the sensor according to the first embodiment. [Figure 16] 16(a) and 16(b) are schematic plan views illustrating a part of the sensor according to the first embodiment. [Figure 17] FIG. 17 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 18] FIG. 18 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 19] FIG. 19 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 20] FIG. 20 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 21] FIG. 21 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 22] FIG. 22 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 23] FIG. 23 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 24] FIG. 24 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 25] FIG. 25 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 26] FIG. 26 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 27] FIG. 27 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 28] FIG. 28 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 29] FIG. 29 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 30] FIG. 30 is a schematic view illustrating an electronic device according to the second embodiment. [Figure 31] 31(a) to 31(h) are schematic views illustrating applications of the electronic device according to the embodiment. [Figure 32] 32(a) and 32(b) are schematic diagrams illustrating applications of the sensor according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios may be different depending on the drawing. In this specification and in each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions thereof will be omitted where appropriate.

[0008] (First embodiment) 1A and 1B are schematic plan views illustrating a part of the sensor according to the first embodiment. FIG. 2 is a schematic plan view illustrating the sensor according to the first embodiment. 3(a) to 3(c) are schematic cross-sectional views illustrating the sensor according to the first embodiment. FIG. 4 is a schematic cross-sectional view illustrating the sensor according to the first embodiment. Fig. 3(a) is a cross-sectional view taken along line Y1-Y2 in Fig. 2. Fig. 3(b) is a cross-sectional view taken along line Y3-Y4 in Fig. 2. Fig. 3(c) is a cross-sectional view taken along line Y5-Y6 in Fig. 2. Fig. 4 is a cross-sectional view taken along line X1-X2 in Fig. 2.

[0009] 2, 3(a) to 3(c), and 4, a sensor 110 according to this embodiment includes a base body 50S and an element unit 10U. The element unit 10U includes a first fixed portion 10F fixed to the base body 50S, a first fixed electrode 51 fixed to the base body 50S, and a first movable portion 10. A first gap 10Z is provided between the base body 50S and the first movable portion 10.

[0010] The first movable portion 10 includes a first movable base portion 10A supported by a first fixed portion 10F, a first other movable base portion 10B connected to the first movable base portion 10A, and a first movable structure 11M.

[0011] The first movable structure 11M includes a first beam 11, a first movable electrode 21, and a first connecting portion 11C. The first beam 11 includes a first beam portion 11a, a first other beam portion 11b, and a first intermediate beam portion 11c. The first intermediate beam portion 11c is provided between the first beam portion 11a and the first other beam portion 11b.

[0012] The second direction D2 from the first beam portion 11a to the first other beam portion 11b intersects with the first direction D1 from the base 50S to the first fixed portion 10F. The first direction D1 is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is defined as the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction. The second direction D2 may be, for example, the X-axis direction.

[0013] The first beam 11 extends, for example, along the second direction D2. The first beam portion 11a is connected to the first movable base portion 10A. The first other beam portion 11b is connected to the first other movable base portion 10B.

[0014] In this example, the first movable part 10 further includes a first movable connecting part 10P. The first movable connecting part 10P is provided between the first movable base part 10A and the first other movable base part 10B. The first movable connecting part 10P is connected to the first movable base part 10A and the first other movable base part 10B. A direction intersecting the direction from the first movable base part 10A to the first other movable base part 10B is defined as the intersecting direction Dx (see FIG. 2). The intersecting direction Dx intersects with the first direction D1. The intersecting direction Dx is, for example, the Y-axis direction. The width of the first movable connecting part 10P in the intersecting direction Dx is narrower than the width of the first movable base part 10A in the intersecting direction Dx and narrower than the width of the first other movable base part 10B in the intersecting direction Dx.

[0015] A third direction D3 from the first beam 11 to the first movable electrode 21 intersects with a plane including the first direction D1 and the second direction D2. The third direction D3 may be, for example, the Y-axis direction. The intersecting direction Dx may be substantially parallel to the third direction D3.

[0016] The first connection portion 11C connects the first movable electrode 21 to the first intermediate beam portion 11c. The first connection portion 11C extends, for example, along the third direction D3.

[0017] 1(a) illustrates a first movable electrode 21 and a first fixed electrode 51. The first movable electrode 21 includes a first movable electrode base 21x and a plurality of first movable protrusions 21p. The plurality of first movable protrusions 21p are connected to the first movable electrode base 21x. The plurality of first movable protrusions 21p are aligned along the second direction D2.

[0018] 1(a), the first fixed electrode 51 includes a first fixed electrode base 51x and a plurality of first fixed protrusions 51p. The plurality of first fixed protrusions 51p are connected to the first fixed electrode base 51x and are aligned along the second direction D2. The plurality of first movable protrusions 21p are interdigitated with the plurality of first fixed protrusions 51p.

[0019] The multiple first movable protrusions 21p include a first movable end protrusion 21a, a first movable other end protrusion 21b, and multiple first movable intermediate protrusions 21c. The first movable end protrusion 21a is one end of the multiple first movable protrusions 21p in the second direction D2. The first movable other end protrusion 21b is the other end of the multiple first movable protrusions 21p in the second direction D2. The multiple first movable intermediate protrusions 21c are provided between the first movable end protrusion 21a and the first movable other end protrusion 21b.

[0020] The width of the first movable end protrusion 21a along the second direction D2 is defined as a first movable end protrusion width w21a. The width of the first movable other end protrusion 21b along the second direction D2 is defined as a first movable other end protrusion width w21b. In the embodiment, the first movable end protrusion width w21a is substantially the same as the first movable other end protrusion width w21b.

[0021] In the embodiment, as shown in FIG. 2, the element unit 10U may further include a first opposing fixed electrode 51A. The first opposing fixed electrode 51A is fixed to the base body 50S. At least a portion of the first movable electrode 21 is provided between the first fixed electrode 51 and the first opposing fixed electrode 51A in the third direction D3. In one example, a first AC signal (drive signal) is applied between the first movable electrode 21 and the first opposing fixed electrode 51A. This causes the first movable structure 11M to vibrate. This vibration causes the first intermediate beam portion 11c of the first beam 11 to vibrate. The vibration includes a component in the third direction D3.

[0022] The multiple first movable protrusions 21p and the multiple first fixed protrusions 51p form a comb-teeth electrode pair. A signal (detection signal) generated between the first movable electrode 21 and the first fixed electrode 51 is detected. In this case, the first movable electrode 21 and the first fixed electrode 51 function as detection electrodes. For example, the phase of vibration is tracked (synchronously detected) from a change in the electrostatic capacitance of the comb-teeth electrode pair to detect a change in the resonant frequency. In the detection electrode, the widths of the two protrusions located at the ends in the second direction D2 are set to be the same. High-precision detection can be stably performed.

[0023] For example, a force is applied to the sensor 110 (e.g., the first movable part 10). This causes the first other movable base part 10B to be displaced. The displacement includes a component in the third direction D3. The displacement of the first other movable base part 10B causes stress to be applied to the first beam 11. The stress is compressive stress or tensile stress. The resonant frequency of the first beam 11 changes depending on the stress applied to the first beam 11. By detecting the change in the resonant frequency, the force (e.g., acceleration) applied to the sensor 110 can be detected.

[0024] In the embodiment, the first movable end protrusion width w21a is substantially the same as the first movable other end protrusion width w21b. This prevents deterioration of detection accuracy. According to the embodiment, a sensor capable of obtaining stable characteristics can be provided.

[0025] As shown in FIG. 1(a), it is desirable that the first movable electrode 21 be line-symmetric with respect to the first line Ln1. The first line Ln1 passes through the first intermediate beam portion 11c and extends along the third direction D3. This allows for a more stable and higher accuracy to be obtained. The first fixed electrode 51 may be line-symmetric with respect to the first line Ln1.

[0026] For example, the first intermediate beam portion 11c is preferably located at the center in the second direction D2 of the first beam 11. This allows for more accurate detection.

[0027] As shown in FIG. 1(a), the multiple first fixed protrusions 51p are provided between the first movable end protrusion 21a and the first movable other end protrusion 21b. The width of each of the multiple first movable intermediate protrusions 21c along the second direction D2 is defined as a first movable intermediate protrusion width w21c. The first movable end protrusion width w21a is greater than the first movable intermediate protrusion width w21c. The first movable other end protrusion width w21b is greater than the first movable intermediate protrusion width w21c.

[0028] The multiple first movable intermediate protrusions 21c are not end protrusions. Each of the multiple first movable intermediate protrusions 21c is sandwiched between one of the multiple first fixed protrusions 51p and another of the multiple first fixed protrusions 51p. In contrast, the first movable end protrusion 21a and the first movable other end protrusion 21b located at the ends are not sandwiched between the multiple first fixed protrusions 51p. The width of such end-positioned protrusions is set larger than the width of the other protrusions. This makes it possible to suppress unintended deformation caused by asymmetric electrostatic attraction on the comb tooth side surfaces. More stable characteristics are easily obtained.

[0029] The first movable end protrusion width w21a may be 1.2 times or more the first movable intermediate protrusion width w21c, and the first movable other end protrusion width w21b may be 1.2 times or more the first movable intermediate protrusion width w21c.

[0030] Practically, the first movable end protrusion width w21a may be the width of the first movable end protrusion 21a along the second direction D2 at the center of the first movable end protrusion 21a in the third direction D3. Practically, the first movable other end protrusion width w21b may be the width of the first movable other end protrusion 21b along the second direction D2 at the center of the first movable other end protrusion 21b in the third direction D3. Practically, the first movable intermediate protrusion width w21c may be the width of one of the multiple first movable intermediate protrusions 21c along the second direction D2 at the center of one of the multiple first movable intermediate protrusions 21c in the third direction D3. As described below, these widths may vary along the third direction D3. In such cases, the above definitions of width may be applied.

[0031] The drive signal is supplied from, for example, the control unit 70 (see FIG. 2). The detection signal is detected by the control unit 70. For example, the control unit 70 is configured to detect a signal generated between the first movable electrode 21 and the first fixed electrode 51. The electrical connection between the control unit 70 and the first movable electrode 21 may be made, for example, via an electrode 10FE provided on the first fixed portion 10F.

[0032] 2, the element portion 10U may further include a second fixed electrode 52. The second fixed electrode 52 is fixed to the base body 50S. The first movable portion 10 may further include a second movable structure 12M. The second movable structure 12M includes a second beam 12, a second movable electrode 22, and a second connection portion 12C.

[0033] The second beam 12 includes a second beam portion 12a, a second other beam portion 12b, and a second intermediate beam portion 12c. The second intermediate beam portion 12c is provided between the second beam portion 12a and the second other beam portion 12b. The direction from the second beam portion 12a to the second other beam portion 12b is along the second direction D2.

[0034] The second beam portion 12a is connected to the first movable base portion 10A. The second other beam portion 12b is connected to the first other movable base portion 10B. The second connecting portion 12C connects the second movable electrode 22 to the second intermediate beam portion 12c.

[0035] In this example, the second beam 12 is provided between the second movable electrode 22 and the first movable electrode 21. The first beam 11 is provided between the second beam 12 and the first movable electrode 21. The first movable connecting part 10P is provided between the second beam 12 and the first beam 11 in the third direction D3. The second movable electrode 22 is provided between the second fixed electrode 52 and the second beam 12.

[0036] 1(b), the second movable electrode 22 includes a second movable electrode base 22x and a plurality of second movable protrusions 22p connected to the second movable electrode base 22x and aligned along the second direction D2. The second fixed electrode 52 includes a second fixed electrode base 52x and a plurality of second fixed protrusions 52p connected to the second fixed electrode base 52x and aligned along the second direction D2. The plurality of second movable protrusions 22p mesh with the plurality of second fixed protrusions 52p in a comb-teeth manner.

[0037] The element portion 10U may further include a second opposing fixed electrode 52A. The second opposing fixed electrode 52A is fixed to the base body 50S. At least a portion of the second movable electrode 22 is provided between the second fixed electrode 52 and the second opposing fixed electrode 52A in the third direction D3.

[0038] In the embodiment, a signal (detection signal) generated between the second movable electrode 22 and the second fixed electrode 52 may be detected. In this case, the second movable electrode 22 and the second fixed electrode 52 function as detection electrodes. On the other hand, an AC signal (drive signal) may be applied between the second movable electrode 22 and the second opposing fixed electrode 52A to vibrate the second beam 12. In this case, the second movable electrode 22 and the second opposing fixed electrode 52A function as drive electrodes.

[0039] For example, a force is applied to the sensor 110 (e.g., the first movable part 10). This causes the first other movable base part 10B to be displaced. The displacement of the first other movable base part 10B causes stress to be applied to the second beam 12. The stress is compressive stress or tensile stress. One of compressive stress and tensile stress is applied to the first beam 11. In this case, the other of compressive stress and tensile stress is applied to the second beam 12.

[0040] For example, by detecting the difference between the first signal obtained from the first movable electrode 21 and the first fixed electrode 51 and the second signal obtained from the second movable electrode 22 and the second fixed electrode 52, detection with higher accuracy is possible.

[0041] 1(b), the plurality of second movable protrusions 22p include a second movable end protrusion 22a, a second movable other end protrusion 22b, and a plurality of second movable intermediate protrusions 22c. The second movable end protrusion 22a is one end of the plurality of second movable protrusions 22p in the second direction D2. The second movable other end protrusion 22b is the other end of the plurality of second movable protrusions 22p in the second direction D2. The plurality of second movable intermediate protrusions 22c are provided between the second movable end protrusion 22a and the second movable other end protrusion 22b.

[0042] The width of the first movable end protrusion 21a along the second direction D2 is defined as the first movable end protrusion width w21a. The width of the first movable other end protrusion 21b along the second direction D2 is defined as the first movable other end protrusion width w21b. In the embodiment, the first movable end protrusion width w21a is substantially the same as the first movable other end protrusion width w21b. This allows for more accurate detection.

[0043] As shown in FIG. 1(b), it is desirable that the second movable electrode 22 be line-symmetric with respect to the second line Ln2. The second line Ln2 passes through the second intermediate beam portion 12c and extends along the third direction D3. This allows for stable and higher accuracy to be obtained. The second fixed electrode 52 may be line-symmetric with respect to the second line Ln2.

[0044] For example, the second intermediate beam portion 12c is preferably located at the center in the second direction D2 of the second beam 12. This allows for more accurate detection.

[0045] As shown in FIG. 1(b), the multiple second fixed protrusions 52p are provided between the second movable end protrusion 22a and the second movable other end protrusion 22b. The width of each of the multiple second movable intermediate protrusions 22c along the second direction D2 is defined as the second movable intermediate protrusion width w22c. The second movable end protrusion width w22a is larger than the second movable intermediate protrusion width w22c. The second movable other end protrusion width w22b is larger than the second movable intermediate protrusion width w22c. For example, unintended deformation caused by asymmetric electrostatic attraction on the comb tooth side surfaces of the end protrusions can be suppressed. More stable characteristics can be easily obtained.

[0046] The second movable end protrusion width w22a may be 1.2 times or more the second movable middle protrusion width w22c, and the second movable other end protrusion width w22b may be 1.2 times or more the second movable middle protrusion width w22c.

[0047] 5(a) and 5(b) are schematic views illustrating the sensor according to the first embodiment. Fig. 5(a) is a plan view, and Fig. 5(b) is a cross-sectional view taken along line X3-X4 of Fig. 5(a). As shown in FIG. 5(a), the first movable section 10 may include a first movable member 10X. The first other movable base 10B is provided between the first movable base 10A and the first movable member 10X in the second direction D2. The first movable member 10X functions as, for example, a proof mass. The width of the first movable member 10X in the third direction D3 is greater than the width of the first other movable base 10B in the third direction D3. The first movable member 10X efficiently transmits externally applied forces to the first beam 11 and the second beam 12. For example, high sensitivity can be obtained.

[0048] As shown in FIG. 1(a), the distance along the third direction D3 between one of the plurality of first movable protrusions 21p and the first fixed electrode base 51x is defined as a first distance d1. The distance along the second direction D2 between one of the plurality of first movable protrusions 21p and one of the plurality of first fixed protrusions 51p is defined as a second distance d2. The one of the plurality of first fixed protrusions 51p is closest to one of the plurality of first movable protrusions 21p among the plurality of first fixed protrusions 51p. For example, no other than the plurality of first fixed protrusions 51p is provided between one of the plurality of first movable protrusions 21p and one of the plurality of first fixed protrusions 51p.

[0049] For example, a first capacitance is formed between the tip of each of the first movable protrusions 21p and the first fixed electrode base 51x. For example, a second capacitance is formed between the side surface of each of the first movable protrusions 21p and the side surface of each of the first fixed protrusions 51p. An electrostatic spring is formed depending on the rate of change of these capacitances.

[0050] It is preferable that the change in the electrostatic spring constant is small when the first movable electrode 21 is displaced along the third direction D3. This facilitates more accurate detection. For example, the change in the first capacitance is small when the first movable electrode 21 is displaced along the third direction D3. The change in the second capacitance is almost zero when the first movable electrode 21 is displaced along the third direction D3.

[0051] For example, if the first distance d1 is too short, the change in the first capacitance relative to the change in the first distance d1 becomes too large. By making the first distance d1 longer than a certain extent, the change in the first capacitance relative to the change in the first distance d1 can be kept small. For example, it is preferable that the first distance d1 be 0.79 times or more the second distance d2. This can reduce the effect of the change in capacitance. For example, it becomes easier to achieve detection with higher accuracy.

[0052] FIG. 6 is a graph illustrating the characteristics of the sensor according to the first embodiment. The horizontal axis of FIG. 6 represents the first ratio r1. The first ratio r1 is the ratio (d1 / d2) of the first distance d1 to the second distance d2. The vertical axis represents the electrostatic spring constant ke1 (μN / μm). FIG. 6 illustrates the characteristics of the sensor 110 and the characteristics of the sensor 119 of the reference example. As already explained, the sensor 110 is provided with a comb-shaped electrode pair. The sensor 119 is provided with a parallel plate electrode pair.

[0053] As shown in FIG. 6, in the sensor 110, as the first ratio r1 increases, the electrostatic spring constant ke1 decreases. When the first ratio r1 is 0.79 or greater, the electrostatic spring constant ke1 in the sensor 110 becomes equal to or less than the electrostatic spring constant ke1 in the sensor 119. For example, when the first ratio r1 is 0.79 or greater, an electrostatic spring constant ke1 equal to or less than the value in a parallel plate electrode pair can be obtained. This reduces the influence of changes in the electrostatic spring constant. This suppresses changes in characteristics caused by changes in the electrostatic spring constant due to warping of the base 50S caused by thermal stress or the like and a change in the first distance d1. For example, it is possible to reduce the influence of characteristic fluctuations due to creep. This makes it easier to stably obtain higher accuracy.

[0054] As shown in FIG. 1(b), the distance along the third direction D3 between one of the second movable protrusions 22p and the second fixed electrode base 52x is defined as a third distance d3. The distance along the second direction D2 between one of the second movable protrusions 22p and one of the second fixed protrusions 52p is defined as a fourth distance d4. The one of the second fixed protrusions 52p is closest to one of the second movable protrusions 22p among the second fixed protrusions 52p. For example, no other second fixed protrusions 52p are provided between one of the second movable protrusions 22p and one of the second fixed protrusions 52p.

[0055] For example, it is preferable that the third distance d3 be 0.79 times or more the fourth distance d4. For example, the influence of the electrostatic spring can be reduced. For example, it is possible to suppress changes in characteristics caused by changes in the electrostatic spring constant due to warping of the base body 50S caused by thermal stress or the like, which changes the third distance d3. For example, it is possible to reduce the influence of characteristic fluctuations due to creep. It becomes easier to stably obtain higher precision.

[0056] 7A and 7B are schematic plan views illustrating a part of the sensor according to the first embodiment. 7A illustrates a first movable electrode 21 in a sensor 110a according to the embodiment. FIG. 7B illustrates a second movable electrode 22 in the sensor 110a. Except for the configuration of these movable electrodes, the configuration of the sensor 110a may be similar to the configuration of the sensor 110.

[0057] In the sensor 110a, the first movable end protrusion width w21a and the first movable other end protrusion width w21b are substantially the same as the first movable intermediate protrusion width w21c. In this case, for example, the first movable electrode 21 is also line-symmetric with respect to the first line Ln1. This high symmetry allows the sensor 110a to achieve high detection accuracy and stable characteristics.

[0058] In the sensor 110a, the second movable end protrusion width w22a and the second movable other end protrusion width w22b are substantially the same as the second movable intermediate protrusion width w22c. In this case, for example, the second movable electrode 22 is also symmetrical with respect to the second line Ln2. This high symmetry allows the sensor 110a to achieve high detection accuracy and stable characteristics.

[0059] 8A and 8B are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of the element unit 10U in a sensor 110b according to this embodiment. As shown in Fig. 8(a), in the sensor 110b, the element unit 10U further includes a first opposing fixed electrode 51A. As shown in Fig. 8(b), in the sensor 110b, the element unit 10U further includes a second opposing fixed electrode 52A. Except for these opposing fixed electrodes, the configuration of the sensor 110b may be similar to the configuration of the sensor 110.

[0060] The first opposing fixed electrode 51A is fixed to the base body 50S. At least a portion of the first movable electrode 21 is provided between the first opposing fixed electrode 51A and the first fixed electrode 51 in the third direction D3.

[0061] The first movable electrode 21 further includes a plurality of first opposing movable protrusions 21Ap. The plurality of first opposing movable protrusions 21Ap are connected to the first movable electrode base 21x and are aligned along the second direction D2. The first movable electrode base 21x is provided between the plurality of first opposing movable protrusions 21Ap and the plurality of first movable protrusions 21p.

[0062] The first opposing fixed electrode 51A includes a first opposing fixed electrode base 51Ax and a plurality of first opposing fixed protrusions 51Ap. The plurality of first opposing fixed protrusions 51Ap are connected to the first opposing fixed electrode base 51Ax and are aligned along the second direction D2. The plurality of first opposing movable protrusions 21Ap are interdigitated with the plurality of first opposing fixed protrusions 51Ap.

[0063] An AC signal may be applied between the first movable electrode 21 and the first opposing fixed electrode 51A, and the signal between the first movable electrode 21 and the first opposing fixed electrode 51A may be detected.

[0064] In the embodiment, an AC signal may be applied between the first movable electrode 21 and the first fixed electrode 51. The signal between the first movable electrode 21 and the first fixed electrode 51 may be detected.

[0065] The second opposing fixed electrode 52A is fixed to the base body 50S. At least a portion of the second movable electrode 22 is provided between the second opposing fixed electrode 52A and the second fixed electrode 52 in the third direction D3.

[0066] The second movable electrode 22 further includes a plurality of second opposing movable protrusions 22Ap. The plurality of second opposing movable protrusions 22Ap are connected to the second movable electrode base 22x and are aligned along the second direction D2. The second movable electrode base 22x is provided between the plurality of second opposing movable protrusions 22Ap and the plurality of second movable protrusions 22p.

[0067] The second opposing fixed electrode 52A includes a second opposing fixed electrode base 52Ax and a plurality of second opposing fixed protrusions 52Ap. The plurality of second opposing fixed protrusions 52Ap are connected to the second opposing fixed electrode base 52Ax and are aligned along the second direction D2. The plurality of second opposing movable protrusions 22Ap are interdigitated with the plurality of second opposing fixed protrusions 52Ap.

[0068] An AC signal may be applied between the second movable electrode 22 and the second opposing fixed electrode 52A, and the signal between the second movable electrode 22 and the second opposing fixed electrode 52A may be detected.

[0069] In an embodiment, an AC signal may be applied between the second movable electrode 22 and the second fixed electrode 52. The signal between the second movable electrode 22 and the second fixed electrode 52 may be detected.

[0070] 9A and 9B are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of the element unit 10U in a sensor 110c according to this embodiment. As shown in FIG. 9(a), in the sensor 110c, at least a portion of the first fixed electrode 51 is provided between at least a portion of the first movable electrode 21 and the first beam 11. As shown in FIG. 9(b), in the sensor 110c, at least a portion of the second fixed electrode 52 is provided between at least a portion of the second movable electrode 22 and the second beam 12. In the sensor 110c, the first opposing fixed electrode 51A and the first movable electrode 21 form a parallel plate electrode pair. In the sensor 110c, the second opposing fixed electrode 52A and the second movable electrode 22 form a parallel plate electrode pair. Except for these, the configuration of the sensor 110c may be similar to that of the sensor 110. Stable characteristics can also be obtained in the sensor 110c.

[0071] 10A and 10B are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of the element unit 10U in a sensor 110d according to this embodiment. In the sensor 110d, the width of the protrusion varies. Except for this, the configuration of the sensor 110d may be similar to the configuration of the sensor 110.

[0072] In the sensor 110d, the first movable intermediate protrusion width w21c decreases with increasing distance from the first movable electrode base 21x. The width of one of the multiple first fixed protrusions 51p along the second direction D2 decreases with increasing distance from the first fixed electrode base 51x.

[0073] In the sensor 110d, the second movable intermediate protrusion width w22c decreases with increasing distance from the second movable electrode base 22x. The width of one of the multiple second fixed protrusions 52p along the second direction D2 decreases with increasing distance from the second fixed electrode base 52x.

[0074] In the sensor 110d, the first movable end protrusion width w21a is also substantially the same as the first movable other end protrusion width w21b. For example, the first movable electrode 21 may be symmetrical with respect to the first line Ln1. For example, the first movable end protrusion width w21a may be larger than the first movable intermediate protrusion width w21c. The first movable other end protrusion width w21b may be larger than the first movable intermediate protrusion width w21c.

[0075] In the sensor 110d, the second movable end protrusion width w22a is also substantially the same as the second movable other end protrusion width w22b. For example, the second movable electrode 22 may be symmetrical with respect to the second line Ln2. For example, the second movable end protrusion width w22a may be larger than the second movable intermediate protrusion width w22c. The second movable other end protrusion width w22b may be larger than the second movable intermediate protrusion width w22c.

[0076] 11A and 11B are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of the element unit 10U in a sensor 110e according to the embodiment. In the sensor 110e, the configuration of the second movable electrode 22 is different from the configuration of the first movable electrode 21. Except for this, the configuration of the sensor 110e may be the same as the configuration of the sensor 110.

[0077] In the sensor 110e, the second movable electrode 22 includes the second hole 22h, and the first movable electrode 21 does not include the first hole. With this configuration, the resonant frequency of the second movable structure 12M including the second movable electrode 22 is different from the resonant frequency of the first movable structure 11M including the first movable electrode 21. For example, a wide dynamic range can be obtained. For example, detection over a wide dynamic range can be performed with high accuracy. For example, a signal obtained from the first movable electrode 21 and a signal obtained from the second movable electrode 22 may be processed.

[0078] In the embodiment, the first movable electrode 21 and the second movable electrode 22 may satisfy at least one of the first condition, the second condition, the third condition, the fourth condition, the fifth condition, the sixth condition, the seventh condition, the eighth condition, and the ninth condition.

[0079] Under the first condition, the second mass of the second movable electrode 22 is different from the first mass of the first movable electrode 21. Under the second condition, the second thickness of the second movable electrode 22 along the first direction D1 is different from the first thickness of the first movable electrode 21 along the first direction D1. Under the third condition, at least a part of the second material contained in the second movable electrode 22 is different from at least a part of the first material contained in the first movable electrode 21.

[0080] , In the fourth condition, the second movable electrode 22 includes the second holes 22h, and the first movable electrode 21 does not include the first holes. In the fifth condition, the second size of the second holes 22h included in the second movable electrode 22 is different from the first size of the first holes included in the first movable electrode 21. In the sixth condition, the second density of the second holes 22h is different from the first density of the first holes.

[0081] In the seventh condition, the second number of the second holes 22h is different from the first number of the first holes. In the eighth condition, the second shape of the second holes 22h is different from the first shape of the first holes. In the ninth condition, the second layer structure of the second movable electrode 22 is different from the first layer structure of the first movable electrode 21.

[0082] 12A and 12B are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of the element unit 10U in a sensor 111 according to the embodiment. In the sensor 111, the configuration of the movable electrode and the fixed electrode is different from that in the sensor 110. Except for this, the configuration of the sensor 111 may be the same as that of the sensor 110.

[0083] In sensor 111, the multiple first fixed protrusions 51p include a first fixed end protrusion 51a, a first fixed other end protrusion 51b, and multiple first fixed intermediate protrusions 51c. The first fixed end protrusion 51a is one end of the multiple first fixed protrusions 51p in the second direction D2. The first fixed other end protrusion 51b is the other end of the multiple first fixed protrusions 51p in the second direction D2. The multiple first fixed intermediate protrusions 51c are provided between the first fixed end protrusion 51a and the first fixed other end protrusion 51b.

[0084] In the embodiment, the first fixed end protrusion width w51a along the second direction D2 of the first fixed end protrusion 51a is substantially the same as the first fixed other end protrusion width w51b along the second direction D2 of the first fixed other end protrusion 51b.

[0085] For example, the multiple first movable protrusions 21p are provided between the first fixed end protrusion 51a and the first fixed other end protrusion 51b. The first fixed end protrusion width w51a is larger than the first fixed intermediate protrusion width w51c of each of the multiple first fixed intermediate protrusions 51c along the second direction D2. The first fixed other end protrusion width w51b is larger than the first fixed intermediate protrusion width w51c.

[0086] For example, the first fixed electrode 51 may be line-symmetric with respect to the first line Ln1. The first line Ln1 passes through the first intermediate beam portion 11c and extends along the third direction D3. The first movable electrode 21 may be line-symmetric with respect to the first line Ln1. For example, unintended deformation of the protrusion is suppressed. Deterioration of detection accuracy is suppressed. According to the embodiment, a sensor capable of obtaining stable characteristics can be provided.

[0087] 13A and 13B are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of the element unit 10U in a sensor 111a according to the embodiment. In the sensor 111a, the first fixed end protrusion width w51a is substantially the same as the first fixed intermediate protrusion width w51c. The first fixed other end protrusion width w51b is substantially the same as the first fixed intermediate protrusion width w51c. Except for this, the configuration of the sensor 111a may be similar to the configuration of the sensor 111. In the sensor 111a, for example, the first fixed electrode 51 is line-symmetric with respect to the first line Ln1. The first movable electrode 21 is line-symmetric with respect to the first line Ln1.

[0088] In the sensor 111a, the second fixed end protrusion width w52a is substantially the same as the second fixed intermediate protrusion width w52c. The second fixed other end protrusion width w52b is substantially the same as the second fixed intermediate protrusion width w52c. In the sensor 111a, for example, the second fixed electrode 52 may be line-symmetric with respect to the second line Ln2. The second movable electrode 22 may be line-symmetric with respect to the second line Ln2.

[0089] 14A and 14B are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of the element unit 10U in a sensor 111b according to this embodiment. In the sensor 111b, the second movable electrode 22 includes a second hole 22h. Except for this, the configuration of the sensor 111b may be similar to the configuration of the sensor 111.

[0090] In the sensor 111b, the first movable electrode 21 and the second movable electrode 22 satisfy at least one of the above first to ninth conditions.

[0091] FIG. 15 is a schematic plan view illustrating a part of the sensor according to the first embodiment. 15 illustrates the configuration of an element unit 10U in a sensor 112 according to the embodiment. In the sensor 112, the first movable structure 11M includes a first other movable electrode 21E. The element unit 10U includes a first other fixed electrode 51E. Except for these, the configuration of the sensor 112 may be similar to that of the sensor 110, etc.

[0092] The first other movable electrode 21E is connected to the first intermediate beam portion 11c. In the third direction D3, the first beam 11 is provided between the first other movable electrode 21E and the first movable electrode 21. The first other movable electrode 21E is line-symmetric to the first movable electrode 21 with the first beam 11 as the axis of symmetry. The first other movable electrode 21E faces the first other fixed electrode 51E.

[0093] The element portion 10U may further include a first other opposing fixed electrode 51EA. The first other opposing fixed electrode 51EA is fixed to the base body 50S. At least a portion of the first other movable electrode 21E is provided between the first other opposing fixed electrode 51E and the first other opposing fixed electrode 51EA in the third direction D3.

[0094] 16(a) and 16(b) are schematic plan views illustrating a part of the sensor according to the first embodiment. These figures illustrate the configuration of an element unit 10U in a sensor 113 according to the embodiment. The sensor 113 is provided with a plurality of first movable electrodes 21. Except for this, the configuration of the sensor 113 may be similar to the configuration of the sensor 110.

[0095] In the sensor 113, the first movable structure 11M includes a plurality of first movable electrodes 21. The first connection portion 11C connects the plurality of first movable electrodes 21 to the first intermediate beam portion 11c. One of the plurality of first movable electrodes 21 is provided between another one of the plurality of first movable electrodes 21 and the first beam 11. The length of one of the plurality of first movable electrodes 21 along the second direction D2 is longer than the length of the other one of the plurality of first movable electrodes 21 along the second direction D2.

[0096] In the sensor 113, the second movable structure 12M includes a plurality of second movable electrodes 22. The second connection portion 12C connects the plurality of second movable electrodes 22 to the second intermediate beam portion 12c. One of the plurality of second movable electrodes 22 is provided between another of the plurality of second movable electrodes 22 and the second beam 12. The length of one of the plurality of second movable electrodes 22 along the second direction D2 is longer than the length of the other one of the plurality of second movable electrodes 22 along the second direction D2. In the sensor 113, the plurality of movable electrodes makes it easier to obtain higher sensitivity, for example.

[0097] Hereinafter, several examples of sensors according to the embodiments will be described. Except for the configuration described below, the configuration of the sensor may be the same as the configuration of the sensor described above.

[0098] 17 to 29 are schematic plan views illustrating the sensor according to the first embodiment. 17, in the sensor 120, the first movable structure 11M includes a plurality of first movable electrodes 21. The second movable structure 12M includes a plurality of second movable electrodes 22. The first movable structure 11M is connected to the first beam 11. The second movable structure 12M is connected to the second beam 12.

[0099] 18, in the sensor 121, the first movable structure 11M includes a first movable electrode 21 and a first other movable electrode 21E. The second movable structure 12M includes a second movable electrode 22 and a second other movable electrode 22E. The first movable electrode 21 faces the first fixed electrode 51. The first other movable electrode 21E faces the first other fixed electrode 51E. The second movable electrode 22 faces the second fixed electrode 52. The second other movable electrode 22E faces the second other fixed electrode 52E.

[0100] 19, in a sensor 122, a first movable structure 11M includes a plurality of first movable electrodes 21. A second movable structure 12M includes a plurality of second movable electrodes 22. The first movable structure 11M is connected to a first beam 11. The second movable structure 12M is connected to a second beam 12.

[0101] As shown in FIG. 20, in the sensor 123, the first movable structure 11M includes a first movable electrode 21 and a first other movable electrode 21E. The second movable structure 12M includes a second movable electrode 22 and a second other movable electrode 22E. The first movable part 10 includes a first other beam 11A and a second other beam 12A. One end of the first other beam 11A is connected to the first movable base 10A. The other end of the first other beam 11A is connected to the first other movable base 10B. One end of the second other beam 12A is connected to the first movable base 10A. The other end of the second other beam 12A is connected to the first other movable base 10B. The first other beam 11A and the second other beam 12A extend along the second direction D2. The first other movable electrode 21E is connected to the first other beam 11A. The first other beam 11A is provided between the first other movable electrode 21E and the first beam 11 in the second direction D2. The second other movable electrode 22E is connected to the second other beam 12A. The second other beam 12A is provided between the second other movable electrode 22E and the second beam 12 in the second direction D2.

[0102] 21, in the sensor 124, the first movable part 10 includes a first other beam 11A and a second other beam 12A. The first other movable electrode 21E is connected to the first other beam 11A. The second other movable electrode 22E is connected to the second other beam 12A. In the sensor 124, a plurality of first movable electrodes 21 and a plurality of first other movable electrodes 21E are provided. A plurality of second movable electrodes 22 and a plurality of second other movable electrodes 22E are provided.

[0103] As shown in FIG. 22, in the sensor 130, the first movable base 10A includes a plurality of regions. One end of the first beam 11 is connected to one of the plurality of regions of the first movable base 10A. The other end of the first beam 11 is connected to the first other movable base 10B. One end of the second beam 12 is connected to another one of the plurality of regions of the first movable base 10A. The other end of the second beam 12 is connected to the first other movable base 10B. The direction from the first beam 11 to the second beam 12 is along the second direction D2. The first movable electrode 21 and the first other movable electrode 21E included in the first movable structure 11M are connected to the first beam 11. The second movable electrode 22 and the second other movable electrode 22E included in the second movable structure 12M are connected to the second beam 12.

[0104] 23 , in the sensor 131, a plurality of first movable electrodes 21 and a plurality of first other movable electrodes 21E are connected to the first beam 11. A plurality of second movable electrodes 22 and a plurality of second other movable electrodes 22E are connected to the second beam 12. Except for this, the configuration of the sensor 131 may be the same as the configuration of the sensor 130.

[0105] 24, in the sensor 132, the first movable electrode 21 is connected to the first beam 11. The first other movable electrode 21E is connected to the first other beam 11A. The second movable electrode 22 is connected to the second beam 12. The second other movable electrode 22E is connected to the second other beam 12A. Except for this, the configuration of the sensor 132 may be the same as the configuration of the sensor 130. The direction from the first other beam 11A to the second other beam 12A is along the second direction D2.

[0106] 25, in the sensor 133, a plurality of first movable electrodes 21 are connected to the first beam 11. A plurality of first other movable electrodes 21E are connected to the first other beam 11A. A plurality of second movable electrodes 22 are connected to the second beam 12. A second other movable electrode 22E is connected to the second other beam 12A. Except for this, the configuration of the sensor 133 may be the same as the configuration of the sensor 132.

[0107] As shown in FIG. 26, in the sensor 140, the first other movable base 10B includes a plurality of regions. One of the regions included in the first other movable base 10B is connected to the first movable base 10A by a plurality of first movable connecting parts 10P. One of the regions included in the first other movable base 10B is provided between one of the plurality of first movable connecting parts 10P and another of the plurality of first movable connecting parts 10P in the third direction D3. Another of the regions included in the first other movable base 10B is connected to the first movable base 10A by a plurality of first movable connecting parts 10P. Another of the regions included in the first other movable base 10B is provided between one of the plurality of first movable connecting parts 10P and another of the plurality of first movable connecting parts 10P in the third direction D3.

[0108] In the sensor 140, the first movable electrode 21 and the first other movable electrode 21E are connected to the first beam 11. The second movable electrode 22 and the second other movable electrode 22E are connected to the second beam 12.

[0109] 27, a plurality of first movable electrodes 21 and a plurality of first other movable electrodes 21E are provided in a sensor 141. A plurality of second movable electrodes 22 and a plurality of second other movable electrodes 22E are provided. Except for this, the configuration of the sensor 133 may be similar to the configuration of the sensor 140.

[0110] As shown in Figure 28, the sensor 142 is provided with a first other beam 11A and a second other beam 12A. The direction from the first other beam 11 to the second beam 12 is along the second direction D2. The direction from the first other beam 11A to the second other beam 12A is along the second direction D2. The direction from the first other beam 11A to the first beam 11 is along the third direction D3. The direction from the second other beam 12A to the second beam 12 is along the third direction D3. Except for this, the configuration of the sensor 142 may be the same as the configuration of the sensor 140.

[0111] 29, in the sensor 143, a plurality of first movable electrodes 21 and a plurality of first other movable electrodes 21E are provided. A plurality of second movable electrodes 22 and a plurality of second other movable electrodes 22E are provided. The plurality of first other movable electrodes 21E are connected to the first other beam 11A. The plurality of second other movable electrodes 22E are connected to the second other beam 12A. Except for this, the configuration of the sensor 143 may be similar to the configuration of the sensor 142.

[0112] In the above sensors 120 to 124, 130 to 133, and 140 to 143, the first movable structure 11M and the second movable structure 12M may satisfy at least one of the above first to ninth conditions. In one example, the second movable electrode 22 included in the second movable structure 12M includes the second holes 22h. The first movable electrode 21 included in the first movable structure 11M does not include the first holes. Alternatively, the number or size of the second holes 22h is different from the number or size of the first holes.

[0113] (Second embodiment) The second embodiment relates to an electronic device. FIG. 30 is a schematic view illustrating an electronic device according to the second embodiment. As shown in FIG. 30 , an electronic device 310 according to an embodiment includes the sensor according to the first embodiment and a circuit control unit 170. In the example of FIG. 30 , a sensor 110 is depicted as the sensor. The circuit control unit 170 can control a circuit 180 based on a signal S1 obtained from the sensor. The circuit 180 is, for example, a control circuit for a drive device 185. According to the embodiment, for example, the circuit 180 for controlling the drive device 185 can be controlled with high precision.

[0114] 31(a) to 31(h) are schematic views illustrating applications of the electronic device according to the embodiment. As shown in FIG. 31(a), the electronic device 310 may be at least a part of a robot. As shown in FIG. 31(b), the electronic device 310 may be at least a part of a machine robot installed in a manufacturing factory or the like. As shown in FIG. 31(c), the electronic device 310 may be at least a part of an automated guided vehicle in a factory or the like. As shown in FIG. 31(d), the electronic device 310 may be at least a part of a drone (unmanned aerial vehicle). As shown in FIG. 31(e), the electronic device 310 may be at least a part of an airplane. As shown in FIG. 31(f), the electronic device 310 may be at least a part of a ship. As shown in FIG. 31(g), the electronic device 310 may be at least a part of a submarine. As shown in FIG. 31(h), the electronic device 310 may be at least a part of an automobile. The electronic device 310 may include, for example, at least one of a robot and a moving object.

[0115] 32(a) and 32(b) are schematic diagrams illustrating applications of the sensor according to the embodiment. As shown in FIG. 32(a), a sensor 430 according to the embodiment includes the sensor according to the first embodiment and a transmitter / receiver 420. In the example of FIG. 32(a), the sensor 110 is depicted as the sensor. The transmitter / receiver 420 can transmit a signal obtained from the sensor 110, for example, wirelessly or by wire. The sensor 430 is provided, for example, on a slope 410 of a road 400 or the like. The sensor 430 can monitor, for example, the condition of a facility (e.g., infrastructure). The sensor 430 may be, for example, a condition monitoring device.

[0116] For example, the sensor 430 detects changes in the condition of the slope surface 410 of the road 400 with high accuracy. The changes in the condition of the slope surface 410 include, for example, at least one of a change in the inclination angle and a change in the vibration state. The signal (inspection result) obtained from the sensor 110 is transmitted by the transceiver unit 420. The condition of a facility (e.g., infrastructure) can be monitored, for example, continuously.

[0117] As shown in FIG. 32(b), the sensor 430 is provided, for example, in a part of a bridge 460. The bridge 460 is provided over a river 470. For example, the bridge 460 includes at least one of a main girder 450 and a pier 440. The sensor 430 is provided in at least one of the main girder 450 and the pier 440. For example, the angle of at least one of the main girder 450 and the pier 440 may change due to deterioration or the like. For example, the vibration state of at least one of the main girder 450 and the pier 440 may change. The sensor 430 detects these changes with high accuracy. The detection result can be transmitted to any location by the transmitter / receiver 420. Abnormalities can be effectively detected.

[0118] The embodiments include the following technical solutions: (Technical proposal 1) a substrate; an element portion; Equipped with The element portion is a first fixed portion fixed to the base; a first fixed electrode fixed to the substrate; A first movable part; Including, a first gap is provided between the base body and the first movable part, The first movable part is a first movable base supported by the first fixed portion; a first other movable base connected to the first movable base; a first movable structure; Including, The first movable structure is The first beam, a first movable electrode; A first connection portion; Including, the first beam includes a first beam portion, a first other beam portion, and a first intermediate beam portion between the first beam portion and the first other beam portion, a second direction from the first beam portion to the first other beam portion intersects with a first direction from the base to the first fixed portion, the first beam portion is connected to the first movable base portion, the first other beam portion is connected to the first other movable base portion, a third direction from the first beam to the first movable electrode intersects with a plane including the first direction and the second direction; the first connection portion connects the first movable electrode to the first intermediate beam portion; the first movable electrode includes a first movable electrode base and a plurality of first movable protrusions connected to the first movable electrode base and aligned along the second direction; the first fixed electrode includes a first fixed electrode base and a plurality of first fixed protrusions connected to the first fixed electrode base and aligned along the second direction; the plurality of first movable protrusions are engaged with the plurality of first fixed protrusions in a comb-teeth shape; the plurality of first movable protrusions include a first movable end protrusion, a first movable other end protrusion, and a plurality of first movable intermediate protrusions; the first movable end protrusion is one end of the plurality of first movable protrusions in the second direction, the first movable other-end protrusion is another end of the plurality of first movable protrusions in the second direction, the plurality of first movable intermediate protrusions are located between the first movable end protrusion and the first movable other end protrusion, A sensor in which the first movable end protrusion width along the second direction of the first movable end protrusion is the same as the first movable other end protrusion width along the second direction of the first movable other end protrusion.

[0119] (Technical proposal 2) the plurality of first fixed protrusions are located between the first movable end protrusion and the first movable other end protrusion, the first movable end protrusion width is greater than the first movable intermediate protrusion width of each of the plurality of first movable intermediate protrusions along the second direction; The sensor described in Technical Solution 1, wherein the width of the first movable other end protrusion is greater than the width of the first movable intermediate protrusion.

[0120] (Technical proposal 3) the first movable electrode is symmetrical with respect to a first line; The sensor described in Technical Solution 1 or 2, wherein the first line passes through the first intermediate beam portion and extends along the third direction.

[0121] (Technical proposal 4) The sensor according to any one of Technical Schemes 1 to 3, wherein the first intermediate beam portion is the center of the first beam in the second direction.

[0122] (Technical proposal 5) the first movable end protrusion width is a width of the first movable end protrusion along the second direction at a center of the first movable end protrusion in the third direction, the width of the first movable other end protrusion is a width of the first movable other end protrusion along the second direction at a center of the first movable other end protrusion in the third direction, The sensor described in Technical Solution 2, wherein the width of the first movable intermediate protrusion is the width of one of the plurality of first movable intermediate protrusions along the second direction at the center of the one of the plurality of first movable intermediate protrusions in the third direction.

[0123] (Technical proposal 6) the width of the first movable intermediate protrusion decreases with increasing distance from the first movable electrode base; A sensor described in technical proposal 5, wherein the width of one of the plurality of first fixed protrusions along the second direction decreases as it moves away from the first fixed electrode base.

[0124] (Technical proposal 7) the plurality of first fixed protrusions include a first fixed end protrusion, a first fixed other end protrusion, and a plurality of first fixed intermediate protrusions; the first fixed end protrusion is one end of the plurality of first fixed protrusions in the second direction, the first fixed other-end protrusion is another end of the plurality of first fixed protrusions in the second direction, the plurality of first fixed intermediate protrusions are located between the first fixed end protrusion and the first fixed other end protrusion, The sensor described in Technical Solution 1, wherein the width of the first fixed end protrusion along the second direction of the first fixed end protrusion is the same as the width of the first fixed other end protrusion along the second direction of the first fixed other end protrusion.

[0125] (Technical proposal 8) the plurality of first movable protrusions are located between the first fixed end protrusion and the first fixed other end protrusion, the first fixed end protrusion width is greater than the first fixed intermediate protrusion widths of the plurality of first fixed intermediate protrusions along the second direction, The sensor described in Technical Solution 7, wherein the width of the first fixed other end protrusion is greater than the width of the first fixed intermediate protrusion.

[0126] (Technical proposal 9) the first movable electrode is symmetrical with respect to a first line; The sensor described in Technical Solution 7 or 8, wherein the first line passes through the first intermediate beam portion and extends along the third direction.

[0127] (Technical proposal 10) The sensor according to any one of Technical Schemes 7 to 9, wherein the first intermediate beam portion is the center of the first beam in the second direction.

[0128] (Technical proposal 11) the first fixed end protrusion width is a width of the first fixed end protrusion along the second direction at a center of the first fixed end protrusion in the third direction, the first fixed other-end protrusion width is a width of the first fixed other-end protrusion along the second direction at a center of the first fixed other-end protrusion in the third direction, The sensor described in Technical Solution 8, wherein the width of the first fixed intermediate protrusion is the width of one of the plurality of first fixed intermediate protrusions along the second direction at the center of the one of the plurality of first fixed intermediate protrusions in the third direction.

[0129] (Technical proposal 12) the width of the first fixed intermediate protrusion decreases with increasing distance from the first fixed electrode base; The sensor described in Technical Solution 11, wherein the width of one of the plurality of first movable protrusions along the second direction decreases as it moves away from the first movable electrode base.

[0130] (Technical proposal 13) a first distance along the third direction between one of the plurality of first movable protrusions and the first fixed electrode base is 0.79 times or more of a second distance along the second direction between the one of the plurality of first movable protrusions and one of the plurality of first fixed protrusions; A sensor described in any one of technical proposals 1 to 12, wherein no other first fixed protrusions are provided between the one of the plurality of first movable protrusions and the one of the plurality of first fixed protrusions.

[0131] (Technical proposal 14) Further comprising a control unit, The sensor according to any one of Technical Schemes 1 to 13, wherein the control unit is configured to detect a signal generated between the first movable electrode and the first fixed electrode.

[0132] (Technical proposal 15) the first movable structure includes a plurality of the first movable electrodes, the first connection portion connects the plurality of first movable electrodes to the first intermediate beam portion; one of the plurality of first movable electrodes is provided between another of the plurality of first movable electrodes and the first beam, A sensor described in any one of technical proposals 1 to 14, wherein the length of one of the plurality of first movable electrodes along the second direction is longer than the length of another of the plurality of first movable electrodes along the second direction.

[0133] (Technical proposal 16) the element portion further includes a second fixed electrode fixed to the base, the first movable portion further includes a second movable structure, The second movable structure is A second beam, A second movable electrode; A second connection portion; Including, the second beam includes a second beam portion, a second other beam portion, and a second intermediate beam portion between the second beam portion and the second other beam portion, a direction from the second beam portion to the second other beam portion along the second direction; the second beam portion is connected to the first movable base portion, the second other beam portion is connected to the first other movable base portion, the second connection portion connects the second movable electrode to the second intermediate beam portion; the second movable electrode includes a second movable electrode base and a plurality of second movable protrusions connected to the second movable electrode base and aligned along the second direction; the second fixed electrode includes a second fixed electrode base and a plurality of second fixed protrusions connected to the second fixed electrode base and aligned along the second direction; The sensor according to any one of Technical Schemes 1 to 15, wherein the plurality of second movable protrusions are interlocked with the plurality of second fixed protrusions in a comb-teeth manner.

[0134] (Technical proposal 17) the element portion further includes a first opposing fixed electrode fixed to the base, The sensor according to any one of Technical Schemes 1 to 16, wherein at least a portion of the first movable electrode is located between the first opposing fixed electrode and the first fixed electrode in the third direction.

[0135] (Technical proposal 18) the element portion further includes a first opposing fixed electrode fixed to the base, at least a portion of the first movable electrode is located between the first opposing fixed electrode and the first fixed electrode in the third direction; the first movable electrode further includes a plurality of first opposing movable protrusions connected to the first movable electrode base and aligned along the second direction; the first movable electrode base is provided between the plurality of first opposing movable protrusions and the plurality of first movable protrusions, the first opposing fixed electrode includes a first opposing fixed electrode base and a plurality of first opposing fixed protrusions connected to the first opposing fixed electrode base and aligned along the second direction; The sensor according to any one of Technical Schemes 1 to 16, wherein the plurality of first opposing movable protrusions mesh with the plurality of first opposing fixed protrusions in a comb-teeth manner.

[0136] (Technical proposal 19) the first movable electrode and the second movable electrode satisfy at least one of a first condition, a second condition, a third condition, a fourth condition, a fifth condition, a sixth condition, a seventh condition, an eighth condition, and a ninth condition; In the first condition, the second mass of the second movable electrode is different from the first mass of the first movable electrode, In the second condition, a second thickness of the second movable electrode along the first direction is different from a first thickness of the first movable electrode along the first direction; In the third condition, at least a part of the second material contained in the second movable electrode is different from at least a part of the first material contained in the first movable electrode; In the fourth condition, the second movable electrode includes a second hole, and the first movable electrode does not include a first hole; In the fifth condition, a second size of the second hole included in the second movable electrode is different from a first size of the first hole included in the first movable electrode; In the sixth condition, the second density of the second holes is different from the first density of the first holes, In the seventh condition, the second number of the second holes is different from the first number of the first holes; In the eighth condition, the second shape of the second hole is different from the first shape of the first hole, The sensor described in Technical Solution 16, wherein in the ninth condition, the second layer structure of the second movable electrode is different from the first layer structure of the first movable electrode.

[0137] (Technical proposal 20) A sensor according to any one of technical proposals 1 to 19; a circuit control unit capable of controlling a circuit based on a signal obtained from the sensor; An electronic device comprising:

[0138] (Technical proposal 21) the first movable part further includes a first movable connection part; the first movable connecting portion is provided between the first movable base portion and the first other movable base portion, the first movable connection part is connected to the first other movable base part and the first movable base part, A sensor described in any one of technical proposals 1 to 19, wherein the width of the first movable connecting part in an intersecting direction intersecting the direction from the first movable base to the first other movable base is narrower than the width of the first movable base in the intersecting direction and narrower than the width of the first other movable base in the intersecting direction.

[0139] (Technical proposal 22) the element portion further includes a second fixed electrode fixed to the base, the first movable portion further includes a second movable structure, The second movable structure is A second movable electrode; A second connection portion; Including, the second connection portion connects the second movable electrode to the first intermediate beam portion; the first beam is provided between the second movable electrode and the first movable electrode in the third direction, the second movable electrode includes a second movable electrode base and a plurality of second movable protrusions connected to the second movable electrode base and aligned along the second direction; the second fixed electrode includes a second fixed electrode base and a plurality of second fixed protrusions connected to the second fixed electrode base and aligned along the second direction; The sensor according to any one of Technical Schemes 1 to 15, wherein the plurality of second movable protrusions are interlocked with the plurality of second fixed protrusions in a comb-teeth manner.

[0140] (Technical proposal 23) the first movable electrode and the second movable electrode satisfy at least one of a first condition, a second condition, a third condition, a fourth condition, a fifth condition, a sixth condition, a seventh condition, an eighth condition, and a ninth condition; In the first condition, the second mass of the second movable electrode is different from the first mass of the first movable electrode, In the second condition, a second thickness of the second movable electrode along the first direction is different from a first thickness of the first movable electrode along the first direction; In the third condition, at least a part of the second material contained in the second movable electrode is different from at least a part of the first material contained in the first movable electrode; In the fourth condition, the second movable electrode includes a second hole, and the first movable electrode does not include a first hole; In the fifth condition, a second size of the second hole included in the second movable electrode is different from a first size of the first hole included in the first movable electrode; In the sixth condition, the second density of the second holes is different from the first density of the first holes, In the seventh condition, the second number of the second holes is different from the first number of the first holes; In the eighth condition, the second shape of the second hole is different from the first shape of the first hole, The sensor described in Technical Proposal 22, wherein in the ninth condition, the second layer structure of the second movable electrode is different from the first layer structure of the first movable electrode.

[0141] A sensor and an electronic device are provided that can obtain stable characteristics.

[0142] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configurations of the elements included in the sensor, such as the substrate, element unit, fixing unit, and control unit, are within the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting them from known ranges.

[0143] Furthermore, any combination of two or more elements of each specific example within the scope of technical feasibility is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0144] In addition, all sensors and electronic devices that can be implemented by a person skilled in the art by appropriately modifying the design based on the sensors and electronic devices described above as embodiments of the present invention also fall within the scope of the present invention, as long as they include the gist of the present invention.

[0145] In addition, within the scope of the concept of the present invention, a person skilled in the art may come up with various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0146] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0147] 10: First movable portion, 10A: First movable base portion, 10B: First other movable base portion, 10F: First fixed portion, 10FE: Electrode, 10P: First movable connecting portion, 10U: Element portion, 10X: First movable member, 10Z: First gap, 11, 12: First and second beams, 11A, 12A: First and second other beams, 11C, 12C: First and second connecting portions, 11M, 12M: First and second movable structures, 11a, 12a: First and second beam portions, 11b, 12b: First and second other beam portions, 11c, 12c: First and second intermediate beam portions, 21, 22: First and second movable electrodes, 21Ap, 22Ap: First and second opposing movable protruding portions, 21E, 22E: first and second movable electrodes, 21a, 22a: first and second movable end protrusions, 21b, 22b: first and second movable other end protrusions, 21c, 22c: first and second movable intermediate protrusions, 21p, 22p: first and second movable protrusions, 21x, 22x: first and second movable electrode bases, 22h: second hole, 50S: base body, 51, 52: first, second fixed electrode, 51A, 52A: first, second opposing fixed electrode, 51Ap, 52Ap: first, second opposing fixed protrusion, 51Ax, 52Ap: base of first, second opposing fixed electrode, 51E, 52E: first, second other fixed electrode, 51EA: 1st other opposing fixed electrode, 51a: first fixed end protrusion, 51b: first fixed other end protrusion, 51c: first fixed intermediate protrusion, 51p, 52p: first and second fixed protrusions, 51x, 52x: first and second fixed electrode bases, 70: control unit, 110, 110a to 110e, 111, 111a, 111b, 112, 113, 119, 120 to 124, 130 to 133, 140 to 143: sensors, 170: circuit control unit, 180: circuit, 185: driving device, 310: electronic device, 400: road, 410: slope surface, 420: transmitter / receiver, 430: sensor, 440: bridge pier, 450: main girder, 460: bridge, 470: river, D1 to D3: first to third directions, Ln1, Ln2: first and second lines, S1: signal, d1 to d4: first to fourth distances, ke1: electrostatic spring constant, r1: first ratio, w21a, w22a: first and second movable end protrusion widths, w21b, w22b: first and second movable other end protrusion widths, w21c, w22c: first and second movable intermediate protrusion widths, w51a, w52a: first fixed end protrusion width, w51b, w52b: first fixed other end protrusion width,w51c, w52c: 1st fixed middle protruding part width

Claims

1. a substrate; an element portion; Equipped with The element portion is a first fixed portion fixed to the base; a first fixed electrode fixed to the substrate; A first movable part; Including, a first gap is provided between the base body and the first movable part, The first movable portion is a first movable base supported by the first fixed portion; a first other movable base connected to the first movable base; a first movable structure; Including, The first movable structure includes: A first beam; a first movable electrode; A first connection portion; Including, the first beam includes a first beam portion, a first other beam portion, and a first intermediate beam portion between the first beam portion and the first other beam portion, a second direction from the first beam portion to the first other beam portion intersects with a first direction from the base to the first fixed portion, the first beam portion is connected to the first movable base portion, the first other beam portion is connected to the first other movable base portion, a third direction from the first beam to the first movable electrode intersects with a plane including the first direction and the second direction; the first connection portion connects the first movable electrode to the first intermediate beam portion; the first movable electrode includes a first movable electrode base and a plurality of first movable protrusions connected to the first movable electrode base and aligned along the second direction; the first fixed electrode includes a first fixed electrode base and a plurality of first fixed protrusions connected to the first fixed electrode base and aligned along the second direction; the plurality of first movable protrusions are engaged with the plurality of first fixed protrusions in a comb-teeth shape; the plurality of first movable protrusions include a first movable end protrusion, a first movable other end protrusion, and a plurality of first movable intermediate protrusions; the first movable end protrusion is one end of the plurality of first movable protrusions in the second direction, the first movable other-end protruding portion is another end of the plurality of first movable protruding portions in the second direction, the plurality of first movable intermediate protrusions are located between the first movable end protrusion and the first movable other end protrusion, A sensor in which the first movable end protrusion width along the second direction of the first movable end protrusion is the same as the first movable other end protrusion width along the second direction of the first movable other end protrusion.

2. the plurality of first fixed protrusions are located between the first movable end protrusion and the first movable other end protrusion, the first movable end protrusion width is greater than the first movable intermediate protrusion widths of the plurality of first movable intermediate protrusions along the second direction, The sensor according to claim 1 , wherein a width of the first movable other end protrusion is greater than a width of the first movable intermediate protrusion.

3. the first movable electrode is symmetrical with respect to a first line; The sensor according to claim 1 , wherein the first line passes through the first intermediate beam portion and extends along the third direction.

4. the plurality of first fixed protrusions include a first fixed end protrusion, a first fixed other end protrusion, and a plurality of first fixed intermediate protrusions; the first fixed end protrusion is one end of the plurality of first fixed protrusions in the second direction, the first fixed other-end protrusion is another end of the plurality of first fixed protrusions in the second direction, the plurality of first fixed intermediate protrusions are located between the first fixed end protrusion and the first fixed other end protrusion, 2. The sensor according to claim 1, wherein a width of the first fixed end protrusion along the second direction of the first fixed end protrusion is the same as a width of the first fixed other end protrusion along the second direction of the first fixed other end protrusion.

5. Further comprising a control unit, 5. The sensor according to claim 1, wherein the control unit is configured to detect a signal generated between the first movable electrode and the first fixed electrode.

6. the first movable structure includes a plurality of the first movable electrodes, the first connection portion connects the plurality of first movable electrodes to the first intermediate beam portion; one of the plurality of first movable electrodes is provided between another of the plurality of first movable electrodes and the first beam, The sensor according to claim 1 , wherein a length of the one of the plurality of first movable electrodes along the second direction is longer than a length of the other of the plurality of first movable electrodes along the second direction.

7. the element portion further includes a second fixed electrode fixed to the base, the first movable portion further includes a second movable structure, The second movable structure is A second beam; A second movable electrode; A second connection portion; Including, the second beam includes a second beam portion, a second other beam portion, and a second intermediate beam portion between the second beam portion and the second other beam portion, a direction from the second beam portion to the second other beam portion is along the second direction; the second beam portion is connected to the first movable base portion, the second other beam portion is connected to the first other movable base portion, the second connection portion connects the second movable electrode to the second intermediate beam portion; the second movable electrode includes a second movable electrode base and a plurality of second movable protrusions connected to the second movable electrode base and aligned along the second direction; the second fixed electrode includes a second fixed electrode base and a plurality of second fixed protrusions connected to the second fixed electrode base and aligned along the second direction; The sensor according to claim 1 , wherein the plurality of second movable protrusions are interdigitated with the plurality of second fixed protrusions.

8. the element portion further includes a first opposing fixed electrode fixed to the base, The sensor according to claim 1 , wherein at least a portion of the first movable electrode is located between the first opposing fixed electrode and the first fixed electrode in the third direction.

9. the element portion further includes a first opposing fixed electrode fixed to the base, at least a portion of the first movable electrode is located between the first opposing fixed electrode and the first fixed electrode in the third direction; the first movable electrode further includes a plurality of first opposing movable protrusions connected to the first movable electrode base and aligned along the second direction; the first movable electrode base is provided between the plurality of first opposing movable protrusions and the plurality of first movable protrusions, the first opposing fixed electrode includes a first opposing fixed electrode base and a plurality of first opposing fixed protrusions connected to the first opposing fixed electrode base and aligned along the second direction; The sensor according to claim 1 , wherein the plurality of first opposing movable protrusions are interdigitated with the plurality of first opposing fixed protrusions.

10. The sensor of claim 1; a circuit control unit capable of controlling a circuit based on a signal obtained from the sensor; An electronic device comprising:

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