JP6969696B2 - Physical quantity sensors, inertial measurement units, electronics, and mobiles - Google Patents

Description

The present invention relates to physical quantity sensors, composite sensors, inertial measurement units, portable electronic devices, electronic devices, and mobile objects.

In recent years, as an example of a physical quantity sensor, a gyro sensor using a gyro sensor element using silicon MEMS (Micro Electro Mechanical System) technology has been developed. Among physical quantity sensors, gyro sensors that detect angular velocities are rapidly expanding in applications such as motion sensing functions of game machines.

As such a gyro sensor, for example, Patent Document 1 discloses a sensor element constituting an angular velocity sensor. This sensor element has a support substrate, a fixed portion fixed to the support substrate, a vibrating body supported by the fixed portion via an elastic beam (support beam), and a comb-teeth shape provided on the vibrating body. It has a movable electrode of the above and a fixed comb tooth electrode that meshes with the movable electrode via an interval. In the angular velocity sensor having such a configuration, when a voltage is applied to the fixed comb tooth electrode, the vibrating body vibrates (drive vibration) in the X-axis direction due to the electrostatic force generated between the movable electrode and the fixed comb tooth electrode. .. When an angular velocity around the Z-axis (or Y-axis) acts on the vibrating body in such a vibrating state, the vibrating body vibrates (detected vibration) in the Y-axis (or Z-axis) direction due to the Coriolis force. The angular velocity of rotation can be detected by detecting an electric signal corresponding to the magnitude of the vibration amplitude in the Y-axis (or Z-axis) direction of the vibrating body due to this Coriolis force.

Such a sensor element can be manufactured by dry etching. For example, in Patent Document 2, _{two systems of reactive plasmas, SF 6} (etching gas) and C ₄ F ₈ (depositing gas), are described. A Si deep reactive ion etching technique, a so-called Bosch process, in which the steps of etching and the volume of the side wall protective film are repeated by alternately switching the gas is described. Deep groove etching is also referred to as deep digging etching.

Japanese Unexamined Patent Publication No. 2009-175079 Special Table No. 7-503815 Gazette

However, when the sensor element described in Patent Document 1 is to be manufactured by the dry etching described in Patent Document 2, if the shape pattern of each part of the sensor element is rough and dense, the etching gas wraps around. Variation occurs, and the cross-sectional shape of each part varies. Specifically, the larger the aperture ratio (pattern), the more the side etching progresses due to the wraparound of the etching gas, and the change in the cross-sectional shape becomes larger. The change is small. When such variation in cross-sectional shape occurs in the elastic portion supporting the vibrating body, the resonance frequency of each portion of the elastic portion varies, which affects the detection signal in the sensor element, and as a result, the detection accuracy is improved. There was a problem that it would drop.

The present invention has been made to solve at least a part of the above-mentioned problems, and can be realized as the following form or application example.

[Application Example 1] The physical quantity sensor according to this application example includes an elastic portion having a plurality of beam portions connected via a folded portion, and an outer beam portion located on the outer side of the plurality of beam portions. When T2 <T1, the outer beam portion is provided with facing structures, the distance between the outer beam portion and the structure is T1, and the distance between the plurality of beam portions is T2. A first beam portion facing the outer beam portion is provided on the structure side of the above.

According to the physical quantity sensor according to this application example, when the distance T1 between the outer beam portion and the structure and the mutual distance T2 between the plurality of beam portions are T2 <T1, in other words, the outer beam portion and the structure. When the aperture ratio between the body and the body is large, the first beam portion facing the outer beam portion is provided on the structure side of the outer beam portion. With this first beam portion, the opening ratio between the outer beam portion and the structure can be reduced, and the opening ratio of each beam portion can be approached. As a result, it is possible to reduce the variation in the cross-sectional shape due to the wraparound of the etching gas, and as a result, it is possible to reduce the decrease in the detection accuracy due to the variation in the resonance frequency of the elastic portion including the plurality of beam portions caused by the variation in the cross-sectional shape. Can be done.

[Application Example 2] In the physical quantity sensor described in the above application example, it is preferable that 0.8 <T3 / T2 <3.0 is satisfied when the distance between the outer beam portion and the first beam portion is T3. ..

According to this application example, it is possible to reduce the variation between the distance between the first beam portion and the outer beam portion (aperture ratio) and the distance between the plurality of beam portions (aperture ratio). In other words, the variation in the cross-sectional shape of the plurality of beams can be reduced within the region where the influence on the resonance frequency is minor, and the variation in the resonance frequency of the elastic portion caused by the variation in the cross-sectional shape of the plurality of beams. Can be reduced.

[Application Example 3] In the physical quantity sensor described in the above application example, it is preferable that 0.8 <T3 / T2 ≦ 2.0 is satisfied.

According to this application example, the variation between the distance between the first beam portion and the outer beam portion (aperture ratio) and the distance between the plurality of beam portions (aperture ratio) has almost an influence on the resonance frequency. The variation in the resonance frequency of the beam portion caused by the variation in the cross-sectional shape of the plurality of beam portions can be further reduced.

[Application Example 4] In the physical quantity sensor described in the above application example, it is preferable to satisfy 0.9 ≦ T3 / T2 ≦ 1.1.

According to this application example, the variation between the distance between the first beam portion and the outer beam portion (aperture ratio) and the distance between the plurality of beam portions (aperture ratio) is set in a region where the influence on the resonance frequency does not appear. It can be made particularly small, and the variation in the resonance frequency of the beam portion caused by the variation in the cross-sectional shape of the plurality of beam portions can be remarkably reduced.

[Application Example 5] In the physical quantity sensor described in the above application example, it is preferable to satisfy T1 ≦ 10 μm.

According to this application example, by setting the distance between the outer beam portion and the structure in this way, a smaller physical quantity sensor can be obtained.

[Application Example 6] In the physical quantity sensor described in the above application example, it is preferable to satisfy 20 μm ≦ D1 ≦ 30 μm when the depth of the beam portion is D1.

According to this application example, when the depth of the beam portion D1 is 20 μm ≦ D1 ≦ 30 μm, the variation in the cross-sectional shape due to the wraparound of the etching gas can be reduced, and as a result, the variation in the cross-sectional shape occurs. It is possible to reduce a decrease in detection accuracy due to variations in the resonance frequencies of a plurality of beams.

[Application Example 7] In the physical quantity sensor described in the above application example, it is preferable that 0 <W1 ≦ 10 μm is satisfied when the width of the beam portion is W1.

According to this application example, when the depth of the beam portion is 20 μm ≦ D1 ≦ 30 μm, the aspect ratio (width / depth) of the beam portion is 1/2 or less, so that the beam portion is compact and has a cross-sectional shape. It is possible to obtain a physical quantity sensor with improved detection accuracy due to variations in the resonance frequencies of a plurality of beams caused by variations in the beam.

[Application Example 8] In the physical quantity sensor described in the above application example, it is preferable that the elastic portion and the structure are provided in the sensor element, and the sensor element is an angular velocity sensor element capable of detecting an angular velocity.

According to this application example, it is possible to reduce the decrease in detection accuracy due to the variation in the resonance frequency of a plurality of beam portions, and to obtain an angular velocity sensor with stable output characteristics.

[Application Example 9] The composite sensor according to this application example includes the physical quantity sensor and the acceleration sensor according to the above application example 8.

According to the composite sensor of this application example, it is possible to easily configure a composite sensor including an angular velocity sensor and an acceleration sensor that reduces a decrease in detection accuracy due to variations in the resonance frequencies of a plurality of beams, and stable angular velocity data. And acceleration data can be acquired.

[Application Example 10] The inertial measurement unit according to the present application example includes the physical quantity sensor according to the above application example 8, an acceleration sensor, and a control unit for controlling the physical quantity sensor and the acceleration sensor.

According to the inertial measurement unit according to this application example, the physical quantity sensor (angular velocity sensor) and the acceleration sensor, which reduce the decrease in detection accuracy due to the variation in the resonance frequency of a plurality of beam portions, are controlled by the control unit. It is possible to obtain an inertial measurement unit that can output highly reliable physical quantity data.

[Application Example 11] The portable electronic device according to this application example includes the physical quantity sensor according to any one of the above application examples, a case in which the physical quantity sensor is housed, and a case in which the physical quantity sensor is housed in the physical quantity sensor. A processing unit that processes output data from the case, a display unit housed in the case, and a translucent cover that closes an opening of the case are included.

According to the portable electronic device according to this application example, since the processing unit controls based on the output data output from the physical quantity sensor described above, the effect of the physical quantity sensor described above can be enjoyed and the reliability is high. A portable electronic device can be obtained.

[Application Example 12] In the portable electronic device described in the above application example, it is preferable to include a satellite positioning system and measure a user's movement distance and movement trajectory.

According to this application example, it is possible to obtain a highly reliable portable electronic device capable of measuring a user's movement distance and movement trajectory by a satellite positioning system.

[Application Example 13] The electronic device according to this application example includes a physical quantity sensor according to any one of the above application examples, and a control unit that controls based on a detection signal output from the physical quantity sensor. There is.

According to the electronic device according to this application example, since the control unit controls based on the detection signal output from the physical quantity sensor described above, the effect of the physical quantity sensor described above can be enjoyed and the electronic device is highly reliable. Can be obtained.

[Application Example 14] The moving body according to this application example includes a physical quantity sensor according to any one of the above application examples, an attitude control unit that controls a posture based on a detection signal output from the physical quantity sensor, and a posture control unit. It is equipped with.

According to the moving body according to this application example, since the attitude control unit controls the posture based on the detection signal output from the physical quantity sensor described above, the effect of the physical quantity sensor described above can be enjoyed and the reliability is high. You can get a high moving object.

[Application Example 15] In the moving body according to the above application example, at least one of an engine system, a brake system, and a keyless entry system is included, and the attitude control unit uses the system based on the detection signal. It is preferable to control.

According to this application example, the attitude control unit controls at least one of the engine system, the brake system, and the keyless entry system based on the detection signal output from the physical quantity sensor described above. You can enjoy the effect of the physical quantity sensor, and you can obtain a highly reliable moving object.

The perspective view which shows the schematic structure of the gyro sensor (angular velocity sensor) which concerns on 1st Embodiment of a physical quantity sensor. FIG. 2 is a cross-sectional view showing a schematic configuration of the gyro sensor shown in FIG. 1. The plan view which shows typically the gyro sensor element shown in FIG. FIG. 3 is a plan view schematically showing a part (part A) of the elastic portion shown in FIG. BB sectional view of FIG. A cross-sectional view illustrating a shape variation caused by a difference in aperture ratio in a dry etching method. The graph which shows the correlation between the interval T1 / interval T2 and the rate of change of the beam width W1 (deep part width W2). The plan view which shows the schematic structure of the gyro sensor which concerns on the 2nd Embodiment of a physical quantity sensor. FIG. 6 is a plan view schematically showing a part (C part) of the elastic part shown in FIG. 7. The plan view which shows the schematic structure of the gyro sensor which concerns on 3rd Embodiment of a physical quantity sensor. FIG. 3 is a plan view schematically showing a part (F portion) of the elastic portion shown in FIG. A functional block diagram showing a schematic configuration of a composite sensor. An exploded perspective view showing a schematic configuration of an inertial measurement unit. The perspective view which shows the arrangement example of the inertia sensor element of an inertial measurement unit. The plan view which shows the structure of the portable electronic device schematically. A functional block diagram showing a schematic configuration of a portable electronic device. The perspective view which shows typically the structure of the mobile type personal computer which is an example of an electronic device. The perspective view which shows typically the structure of the smartphone (mobile phone) which is an example of an electronic device. The perspective view which shows the structure of the digital still camera which is an example of an electronic device. The perspective view which shows the structure of the automobile which is an example of a moving body.

Hereinafter, the physical quantity sensor, the composite sensor, the inertial measurement unit, the portable electronic device, the electronic device, and the moving body of the present invention will be described in detail based on the embodiments shown in the accompanying drawings.

1. 1. Physical quantity sensor <First embodiment>
First, as an embodiment of the physical quantity sensor, a gyro sensor (angular velocity sensor) will be illustrated and described with reference to FIGS. 1, 2, and 3. FIG. 1 is a perspective view showing a schematic configuration of a gyro sensor (angular velocity sensor) according to the first embodiment of the physical quantity sensor of the present invention. FIG. 2 is a cross-sectional view showing a schematic configuration of the gyro sensor shown in FIG. FIG. 3 is a plan view schematically showing the gyro sensor element shown in FIG. In FIG. 1, the substrate (base) is schematically shown, and the lid member is not shown. Further, in the description of each embodiment of the physical quantity sensor, the three axes orthogonal to each other will be referred to as an X-axis (third axis), a Y-axis (first axis), and a Z-axis (second axis). Further, the direction along the X-axis is also referred to as "X-axis direction", the direction along the Y-axis direction is also referred to as "Y-axis direction", and the direction along the Z-axis is also referred to as "Z-axis direction". Further, the Z-axis is an axis indicating the thickness direction in which the substrate and the lid member overlap, and the Y-axis is an axis along the driving direction of the gyro sensor element. Further, for convenience of explanation, in a plan view when viewed from the Z-axis direction, the + Z-axis direction side, which is the lid member side, is "upper" or the + Z-axis direction side is the "upper surface", which is the opposite side. The Z-axis direction side may be described as "downward" or the -Z-axis direction side surface may be described as "lower surface". Further, in each drawing, for convenience of explanation, the dimensions of each part are exaggerated as necessary, and the dimensional ratio between the parts does not always match the actual dimensional ratio.

[Gyro sensor]
As shown in FIG. 1, the gyro sensor 1 according to the first embodiment of the physical quantity sensor is an angular velocity sensor capable of detecting an angular velocity around the X-axis. As shown in FIG. 2, the gyro sensor 1 has a gyro sensor element (angular velocity sensor element) 4 as a sensor element and a package 10 containing the gyro sensor element 4.

(package)
The package 10 has a substrate 2 (base) that supports the gyro sensor element 4, and a lid member 3 that is joined to the substrate 2. A space S for accommodating the gyro sensor element 4 is formed between the substrate 2 and the lid member 3. The substrate 2 and the lid member 3 each have a plate shape and are arranged along an XY plane (reference plane) which is a plane including the X-axis and the Y-axis.

The substrate 2 is provided with a recess 21 that opens upward (on the gyro sensor element 4 side). At the center of the recess 21, a protrusion 22 protruding from the bottom surface 212 of the recess 21 is provided. Further, a part of the gyro sensor element 4 (fixed portion 42 and fixed drive portions 45, 46 described later) is fixed to the upper surface 23 excluding the recess 21 of the substrate 2.

The lid member 3 is provided with a recess 31 that opens downward (on the substrate 2 side). The lid member 3 is provided on the substrate 2 so as to cover the gyro sensor element 4 in a non-contact manner, and the lower surface 33 excluding the recess 31 is joined to the upper surface 23 of the substrate 2.

Further, the space S that functions as a cavity is an airtight space formed by the recess 21 and the recess 31, and is in a depressurized state (for example, about 1 × 10 ² to 1 × 10 ⁻² Pa). This makes it possible to improve the detection sensitivity of the angular velocity.

The constituent material of the substrate 2 is not particularly limited, but it is preferable to use a material having insulating properties, and specifically, it is preferable to use a high resistance silicon material or a glass material, for example, an alkali metal ion (movable). It is preferable to use a glass material containing a certain amount of ions (eg, borosilicate glass such as Pyrex® glass). As a result, when the gyro sensor element 4 is made of silicon as the main material, the substrate 2 and the gyro sensor element 4 can be anodically bonded. Other than that, it may be a quartz substrate, a crystal substrate, or an SOI (Silicon on Insulator) substrate.

Further, the constituent material of the lid member 3 is not particularly limited, and for example, the same material as the substrate 2 described above can be used.

The method of joining the substrate 2 and the lid member 3 is not particularly limited, and varies depending on the constituent materials of the substrate 2 and the lid member 3. As a method of joining the substrate 2 and the lid member 3, for example, a joining method using a joining material such as an adhesive or a brazing material, a direct joining method, a solid joining method such as an anode joining, or the like can be used.

(Gyro sensor element)
As shown in FIG. 3, the gyro sensor element (angular velocity sensor element) 4 as a sensor element consists of two element bodies 40 (40a, 40b) arranged in the Y-axis direction and two fixed detection units 49 (49a, 49b). ) And. In FIG. 3, the two element bodies 40a and 40b are vertically symmetrically configured in the + (plus) Y-axis direction and the − (minus) Y-axis direction, and have similar configurations to each other.

Each element body 40a, 40b has a mass portion 41, a plurality of fixed portions 42, a plurality of elastic portions 43, a plurality of drive portions 44 (movable drive electrodes), and a plurality of fixed drive portions 45, 46 (fixed drive). It has an electrode), a detection unit 471, 472 (movable detection electrode), and a plurality of support beam portions 48. The mass portion 41 is integrally formed with the drive portion 44, the frame 473, the detection portions 471, 472, and the support beam portion 48. That is, the detection units 471 and 472 have a shape included in the mass unit 41.

The outer shape of the mass portion 41 has a quadrangular frame shape in a plan view seen from the Z-axis direction (hereinafter, simply referred to as “plan view”), and as described above, the drive unit 44, the frame 473, and the detection It is configured to include parts 471 and 472. Specifically, the outer shape of the mass portion 41 is such that a pair of portions extending in parallel with each other along the Y-axis direction and the ends of the pair of portions are connected to each other and parallel to each other along the X-axis direction. It is composed of a pair of extending parts.

Four fixing portions 42 are provided for one element body 40, and each fixing portion 42 is fixed to the upper surface 23 of the substrate 2 described above. Further, each fixing portion 42 is arranged outside the mass portion 41 in a plan view, and in the present embodiment, is arranged at a position corresponding to each corner portion of the mass portion 41. In the figure, the fixing portion 42 located on the −Y axis side of the element body 40a and the fixing portion 42 located on the + Y axis side of the element body 40b are common fixing portions.

Four elastic portions 43 are provided for one element body 40 in this embodiment, and each elastic portion 43 connects a part of the mass portion 41 and the fixed portion 42 in a plan view. .. In the present embodiment, the elastic portion 43 is connected to the corner portion of the frame 473 in the mass portion 41, but the present invention is not limited to this, as long as the mass portion 41 can be displaced with respect to the fixed portion 42. In FIG. 3, the mass portion 41 is configured to be able to be displaced in the Y-axis direction. Further, in the figure, each elastic portion 43 has a meandering shape in a plan view, and constitutes a first portion 4301a, 4301b, 4301c, 4301d and a folded portion 430 as a plurality of beam portions extending along the X-axis direction. It also has a second portion 4302 extending along the Y-axis direction (see FIG. 4). The shape of the elastic portion 43 is not limited to the shape shown in the figure as long as it can be elastically deformed in a desired driving direction (Y-axis direction in this embodiment).

Eight drive units 44 are provided for one element body 40, and each drive unit 44 is connected to a portion of the mass unit 41 extending along the Y-axis direction. Specifically, the four drive units 44 are located on the + X side of the mass unit 41, and the remaining four drive units 44 are located on the −X side of the mass unit 41. Each drive unit 44 has a comb-teeth shape including a trunk portion extending in the X-axis direction from the mass portion 41 and a plurality of branch portions extending in the Y-axis direction from the trunk portion.

Eight fixed drive units 45 and 46 are provided for each element body 40, and each of the fixed drive units 45 and 46 is fixed to the upper surface 23 of the substrate 2 described above. Further, the fixed drive units 45 and 46 have a comb tooth shape corresponding to the drive unit 44, and are provided with the drive unit 44 interposed therebetween.

Each of the detection units 471 and 472 is a plate-shaped member having a rectangular shape in a plan view, is arranged inside the mass portion 41, and is connected to the mass portion 41 by the support beam portion 48. The detection units 471 and 472 can rotate (displace) around the rotation shaft J4, respectively.

Further, the fixed detection unit 49 (fixed detection electrode) is provided on the protruding portion 22 located in the recess 21 of the substrate 2 (see FIG. 2). The fixed detection units 49 each have a rectangular shape in a plan view and face the detection units 471 and 472. Further, the fixed detection unit 49 is separated from the detection units 471 and 472.

Further, the mass part 41, the elastic part 43, the drive part 44, a part of the fixed drive part 45, a part of the fixed drive part 46, the detection part 471, 472, and the support beam part 48 having the above-described configuration are also included. Is provided above the recess 21 of the substrate 2 and is separated from the substrate 2.

The element body 40 as described above is a Bosch method in which a conductive silicon substrate doped with impurities such as phosphorus and boron is combined with, for example, an etching process using a reactive plasma gas and a deposition process (deposition). It is collectively formed by patterning by using Bosch process).

Further, as the constituent material of the fixed detection unit 49, for example, aluminum, gold, platinum, ITO (Indium Tin Oxide), ZnO (zinc oxide), or a combination thereof can be used.

Although not shown, the fixed unit 42, the fixed drive unit 45, the fixed drive unit 46, the fixed detection unit 49a, and the fixed detection unit 49b are electrically connected to wirings and terminals (not shown), respectively. ing. These wirings and terminals are provided, for example, on the substrate 2.

The configuration of the gyro sensor 1 has been briefly described above. The gyro sensor 1 having such a configuration can detect the angular velocity ωx as follows.

First, when a drive voltage is applied between the drive unit 44 of the gyro sensor 1 and the fixed drive units 45, 46, the electrostatic strength changes periodically between the fixed drive units 45, 46 and the drive unit 44. An attractive force is generated. As a result, each drive unit 44 vibrates in the Y-axis direction with elastic deformation of each elastic unit 43. At this time, the plurality of drive units 44 included in the element body 40a and the plurality of drive units 44 included in the element body 40b vibrate (drive vibration) in opposite phases in the Y-axis direction.

When the angular velocity ωx is applied to the gyro sensor 1 in the state where the drive unit 44 is vibrating in the Y-axis direction, the Coriolis force acts and the detection units 471 and 472 are displaced around the rotation shaft J4. At this time, the detection units 471 and 472 included in the element body 40a and the detection units 471 and 472 included in the element body 40b are displaced in opposite directions. For example, when the detection units 471 and 472 included in the element body 40a are displaced in the + Z axis direction, the detection units 471 and 472 included in the element body 40b are displaced in the −Z axis direction, respectively. Further, when the detection units 471 and 472 included in the element body 40a are displaced in the −Z axis direction, the detection units 471 and 472 included in the element body 40b are displaced in the + Z axis direction, respectively.

As the detection units 471 and 472 are displaced (detection vibration) in this way, the distance between the detection units 471 and 472 and the fixed detection unit 49 changes. With this change in distance, the capacitance between the detection units 471 and 472 and the fixed detection unit 49 changes. Then, based on the amount of change in the capacitance, the angular velocity ωx applied to the gyro sensor 1 can be detected.

As described above, when the drive unit 44 vibrates in the Y-axis direction (drive vibration), ideally, it is preferable that the drive unit 44 vibrates substantially parallel to the Y-axis direction from the non-drive state. However, the shape of the gyro sensor element 4 may not be an ideal shape due to a processing error or the like. In particular, in the shape of the beam portion (first portion 4301a, 4301b, 4301c, 4301d) constituting the elastic portion 43, for example, the width W1 of the beam portion (see FIG. 4) may vary, or the cross-sectional shape of the beam portion may change. Events such as not having the ideal rectangular shape occur. In this way, if the width W1 of the beam portion (see FIG. 4) varies, the resonance frequency of the elastic portion 43 also varies. Further, if the cross-sectional shape of the beam portion is not rectangular, the vibration of the drive portion 44 connected to the elastic portion 43 via the mass portion 41 is not only the vibration component in the Y-axis direction, which is the desired drive vibration direction, but also the vibration component. The so-called quadrature signal, which also includes vibration components (unnecessary vibration components) in the X-axis direction or the Z-axis direction, which are other vibration directions, increases.

In the present embodiment, the configuration of the elastic portion 43 is characterized so that the variation in the resonance frequency of the elastic portion 43 can be reduced and the increase in the quadrature signal can be reduced. Hereinafter, the elastic portion 43 will be described in detail with reference to FIGS. 4, 5, 6A, and 6B.

(Elastic part)
FIG. 4 is a plan view schematically showing a part (part A) of the elastic portion shown in FIG. Note that FIG. 4 is shown on behalf of the elastic portion 43 in the portion A surrounded by the alternate long and short dash line shown in FIG. FIG. 5 is a cross-sectional view taken along the line BB of FIG. 4 schematically showing a part of the elastic portion. FIG. 6A is a cross-sectional view illustrating the shape variation caused by the difference in aperture ratio in the dry etching method. FIG. 6B is a graph showing the correlation between the interval T1 / interval T2 and the rate of change of the beam width W1 (deep width W2). The interval T1 in FIG. 6B is the interval between the beam portion and the structure, and the interval T2 is the interval between the beam portion and the adjacent beam portion.

As shown in FIG. 4, the elastic portion 43 has a meandering shape in a plan view. The elastic portion 43 includes first portions 4301a, 4301b, 4301c, 4301d as a plurality of long beam portions extending along the X-axis direction (longitudinal direction), and a plurality of extending along the Y-axis direction (shortward direction). It has a second portion 4302 of the above and a plurality of first beam portions 4303 connected to each of the two first portions 4301a and 4301d. The first portion 4301a, 4301b, 4301c, 4301d is longer than the second portion 4302. Further, the first portions 4301a, 4301b, 4301c, and 4301d refer to portions separated by broken lines QL1, QL2, QL3, QL4, QL5, QL6, QL7, and QL8, respectively, as general boundary lines. The second portion 4302 constitutes a so-called folded portion 430 in which the adjacent first portions 4301a, 4301b, 4301c, 4301d are connected and folded back. The plurality of first portions 4301a, 4301b, 4301c, 4301d are folded back by the folded-back portion 430 including the second portion 4302 to form a meandering shape. Further, one end of the elastic portion 43 is connected to the end portion of the mass portion 41 indicated by the broken line QL7 in the figure, and the other end thereof is connected to the end portion of the fixed portion 42 indicated by the broken line QL1 in the figure.

The elastic portion 43 of the present embodiment includes four first portions 4301a, 4301b, 4301c, 4301d. The four first portions 4301a, 4301b, 4301c, 4301d are arranged in parallel with a distance T2 from each other. The first portion 4301a, 4301b, 4301c, 4301d includes a first portion 4301a and a first portion 4301d as two outer beam portions located on the outer side, and a first portion 4301a and a first portion 4301d as outer beam portions. It can be divided into a first portion 4301b and a first portion 4301c as two inner beam portions located between them. The first portion 4301a, 4301b, 4301c, 4301d is folded back by the folded-back portion 430 including the second portion 4302 to form a meandering shape. Further, one end of the elastic portion 43 is connected to the mass portion 41, and the other end thereof is connected to the fixed portion 42.

One end of the first portion 4301a as the outer beam portion is connected to the mass portion 41 and is arranged so as to face the fixed drive portion 45 as a structure. The first portion 4301a has a distance T1 from the fixed drive unit 45 and extends along the outer edge of the fixed drive unit 45. One end of the first portion 4301d as the other outer beam portion is connected to the fixed portion 42 and is arranged on the opposite side to the fixed drive portion 45.

One end of the first portion 4301b as one inner beam portion is connected to the first portion 4301a via the second portion 4302, and the other end is connected to the first portion 4301c via the other second portion 4302. ing. The first portion 4301c as the other inner beam portion connected to the first portion 4301b via the second portion 4302 at the other end is connected to the first portion 4301d via the other second portion 4302 at one end. ing.

The four first portions 4301a, 4301b, 4301c, and 4301d are configured to satisfy the width W1 in the direction orthogonal to the longitudinal direction (X-axis direction) (Y-axis direction) to 0 <W1 ≦ 10 (μm). It is preferable to do so. When the depth D1 (see FIG. 6A) is 20 μm ≦ D1 ≦ 30 μm by configuring the first part 4301a, 4301b, 4301c, 4301d as described above, the first part 4301a, 4301b, 4301c, 4301d Since the aspect ratio (width / depth) is halved or less, the gyro sensor 1 is compact and detects due to the variation in the resonance frequency of the plurality of first portions 4301a, 4301b, 4301c, 4301d caused by the variation in the cross-sectional shape. The accuracy can be improved.

The second portion 4302 is provided so as to extend in the longitudinal direction of the first portions 4301a, 4301b, 4301c, 4301d and along the Y-axis direction (short direction) intersecting the X-axis direction. The second portion 4302 constitutes a so-called folded portion 430 in which the first portion 4301a and the adjacent first portion 4301b are connected at the end on the + X axis side and folded back. Similarly, the second portion 4302 connects the first portion 4301b and the adjacent first portion 4301c at the end on the −X axis side and folds back, and the first portion 4301c and the adjacent first portion 4302. A folded-back portion 430 is configured by connecting the portion 4301d at the end on the + X-axis side and folding back.

The first beam portion 4303 is arranged between the first portion 4301a and the fixed drive portion 45 as a structure. The first beam portion 4303 has an interval T3 between the first beam portion 4301a and the first beam portion 4301a, and is connected to the first portion 4301a via the connecting portion 4304. In this embodiment, two first beam portions 4303 are provided. The two first beam portions 4303 have a gap Q at a position facing the central portion in the longitudinal direction of the first portion 4301a, and extend along the longitudinal direction of the first portion 4301a. The first beam portion 4303 refers to a portion shown by hatching in the drawing as an approximate shape.

The first beam portion 4303 is provided in order to reduce variations in the cross-sectional shape of the first portion 4301a particularly during dry etching such as the Bosch process used for forming the gyro sensor element 4. It should be noted that this variation in the cross-sectional shape is caused by the difference in the wraparound of the etching gas during dry etching, which is caused by the density of the shape pattern of each portion of the gyro sensor element 4. Hereinafter, in dry etching, variations in the cross-sectional shape of each portion caused by the density of the shape pattern will be described with reference to FIGS. 6A and 6B.

In dry etching such as the Bosch method, the larger the aperture ratio, in other words, the larger the distance (pattern) from the adjacent part, the easier it is for the etching gas to wrap around, and the side etching by the wraparound etching gas is performed. As it progresses, the change in cross-sectional shape becomes large. On the other hand, in the part where the aperture ratio is small, in other words, the part (pattern) where the distance from the adjacent part is small, the change in the cross-sectional shape becomes small (microloading effect).

Specifically, a processing example of a pattern simulating the elastic portion 43 shown in FIG. 6A will be illustrated and described. FIG. 6A shows a cross section when deep etching is performed at a depth D1 of 20 μm to 30 μm (20 μm ≦ D1 ≦ 30 μm) by the Bosch method. As shown in FIG. 6A, the first portion 4301a as the outer beam portion arranged with the spacing T1 between the fixed drive portion 45 and the first portion 4301a are arranged with the spacing T2. The first portion 4301b as the inner beam portion is dry-etched using the Bosch method. In this example, the distance T1 between the first portion 4301a and the fixed drive unit 45 satisfies the relationship T2 <T1 with respect to the distance T2 between the first portion 4301a and the first portion 4301b. That is, the pattern is such that the aperture ratio between the first portion 4301a and the fixed drive unit 45 is larger than that between the first portion 4301a and the first portion 4301b. When dry etching is performed in such a pattern, as shown in FIG. 6A, side etching easily proceeds between the first portion 4301a and the fixed drive portion 45, which have a large aperture ratio (interval T1), and the size is small. Side etching is difficult to proceed between the first portion 4301a and the first portion 4301b having an aperture ratio (interval T2).

The distance T1 between the first portion 4301a and the fixed drive unit 45 preferably satisfies T1 ≦ 10 (μm). By setting the distance T1 between the first portion 4301a as the outer beam portion and the fixed drive portion 45 as the structure in this way, the gyro sensor 1 can be made smaller.

As described above, the first portion 4301a causes side etching on the side surface on the side of the fixed drive portion 45, and the bottom portion dug deeper than the width W1 of the first portion 4301a on the first main surface 431 where etching is started. The deep width W2 of the 1st portion 4301a becomes smaller. On the other hand, since the first portion 4301b has an interval T2 on both the first portion 4301a side and the first portion 4301c side, the first main portion 4301b is formed with almost no side etching and the etching is started. The width W1 of the first portion 4301b on the surface 431 and the deep width W3 of the first portion 4301b of the deeply dug bottom portion are substantially equal to each other.

As described above, there is a difference in the cross-sectional shape between the first portion 4301a having a pattern having a large aperture ratio and the first portion 4301b having no pattern having a large aperture ratio, that is, the cross-sectional shapes vary. Then, due to this variation in the cross-sectional shape, the resonance frequency of the elastic portion 43 (first portion 4301a, other first portion 4301b, first portion 4301c, 4301d) supporting the mass portion 41 varies. In other words, the resonance frequency of the mass portion 41 supported by the elastic portion 43 varies, which affects the detection signal in the gyro sensor element 4.

The first beam portion 4303 is arranged between the first portion 4301a having a large aperture ratio (interval T1) and the fixed drive portion 45, and the opening ratio of the first portion 4301a on the fixed drive portion 45 side can be reduced. .. The first beam portion 4303 is arranged on the fixed drive portion 45 side of the first portion 4301a so that the distance T3 from the first portion 4301a satisfies 0.8 <T3 / T2 <3.

In the graph of FIG. 6B, the distance T1 between the first portion 4301a and the fixed drive unit 45 in the example shown in FIG. 6A and the distance T2 between the first portion 4301a and the adjacent first portion 4301b are shown. The correlation between the ratio (T1 / T2 ratio) and the rate of change of the deep width W2 with respect to the width W1 of the first portion 4301a is shown. As shown in the graph of FIG. 6B, in the region where the T1 / T2 ratio is 3.0 or more, the deep portion width W2 in the deep portion is relative to the width W1 of the first main surface 431 of the first portion 4301a. The rate of change exceeds 4%. Then, at such a rate of change of the width W1 exceeding 4%, the resonance frequency of the elastic portion 43 may vary. Therefore, it is not preferable to set the T1 / T2 ratio so that it exceeds 3.0. In other words, the first beam portion 4303 has a T3 / T2 ratio which is the ratio of the distance T3 between the first portion 4301a and the distance T2 between the first portion 4301a and the adjacent first portion 4301b. , 3.0 or less (T3 / T2 <3), preferably facing the first portion 4301a.

As shown in the graph of FIG. 6B, when the T1 / T2 ratio is 0.8 or less, that is, when the interval (gap) is narrow, the width W1 of the first portion 4301a becomes large due to the microloading effect. Etching does not penetrate at narrow gap settings. Therefore, in the first beam portion 4303, the T3 / T2 ratio, which is the ratio of the distance T3 between the first portion 4301a and the distance T2 between the first portion 4301a and the adjacent first portion 4301b, is 0. It is preferable to set so as to satisfy .8 <T3 / T2 <3.

In this way, the elastic portion 43 has the first portion by arranging the first beam portion 4303 with respect to the first portion 4301a so that the T3 / T2 ratio is 0.8 <T3 / T2 <3. The variation in the cross-sectional shape between the 4301a and the other first portions 4301b, 4301c, 4301d can be reduced and penetrated, and the variation in the resonance frequency of the elastic portion 43 (mass portion 41) can be reduced.

It is more preferable that the distance T3 between the first beam portion 4303 and the first portion 4301a satisfies 0.8 <T3 / T2 ≦ 2.0. When the T3 / T2 ratio is set in this way, as shown in the graph of FIG. 6B, the rate of change of the deep portion width W2 with respect to the width W1 of the first portion 4301a becomes as slight as about 2%, and the first portion The variation in the cross-sectional shape between the 4301a and the other first portion 4301b, the first portion 4301c, and 4301d can be further reduced and penetrated, and the variation in the resonance frequency of the elastic portion 43 (mass portion 41) is further reduced. be able to.

Further, it is more preferable that the distance T3 between the first beam portion 4303 and the first portion 4301a satisfies 0.9 ≦ T3 / T2 ≦ 1.1. When the T3 / T2 ratio is set in this way, as shown in the graph of FIG. 6B, the change in the deep width W2 with respect to the width W1 in the first portion 4301a is within 10%, and the change in the width W1 is almost the same. It disappears and can be penetrated by making the variation in the cross-sectional shape between the first portion 4301a and the other first portion 4301b, the first portion 4301c, and 4301d particularly small. As a result, it is possible to significantly reduce the variation in the resonance frequency of the elastic portion 43 (mass portion 41) caused by the variation in the cross-sectional shape of the plurality of first portions 4301a, 4301b, 4301c, 4301d.

The first beam portion 4303 is not limited to the first portion 4301a on the fixed drive portion 45 side, but may be provided on the first portion 4301d located on the opposite side to the fixed drive portion 45 side. In this case, the first beam portion 4303a is arranged via the connecting portion 4304a so as to face the first portion 4301d on the opposite side of the first portion 4301c. Here, the arrangement pattern (arrangement configuration) such as the distance between the first portion 4301d and the first beam portion 4303a may be the same as that of the first beam portion 4303 on the fixed drive portion 45 side described above.

The first portions 4301a, 4301b, 4301c, 4301d constituting the elastic portion 43 have a shape from the direction along the X-axis direction (a cross-sectional shape parallel to the YZ plane which is a plane including the Y-axis and the Z-axis). It has a rectangular shape. The outer peripheral surfaces of the first portion 4301a, 4301b, 4301c, 4301d include a first main surface 431 and a second main surface 432 (see FIG. 5) as a pair of main surfaces, and a first side surface 433 and a pair of side surfaces. It has a second side surface 434 and.

The first main surface 431 and the second main surface 432 are flat surfaces along the XY plane, which are planes including the X-axis and the Y-axis, respectively. The first main surface 431 is a surface (upper surface) on the + Z axis side, and the second main surface 432 is a surface (lower surface) on the −Z axis side. In the present embodiment, the first main surface 431 and the second main surface 432 each have a meandering shape and have a portion extending along the X-axis direction and a portion extending along the Y-axis direction.

The first side surface 433 is a surface on the −Y axis side, and the second side surface 434 is a surface on the + Y axis side. In the present embodiment, four first side surfaces 433 and four second side surfaces 434 are provided for one elastic portion 43 (see FIG. 4). The + Z-axis side side of the first side surface 433 is connected to the first main surface 431, and the −Z-axis side side is connected to the second main surface 432. On the other hand, the + Z-axis side side of the second side surface 434 is connected to the first main surface 431, and the −Z-axis side side of the second side surface 434 is connected to the second main surface 432.

Here, as described above, the gyro sensor 1 has a substrate 2, a fixing portion 42 fixed to the substrate 2, and a driving portion 44 that drives in the first direction along the Y axis as the "first axis". And the detection unit 471, 472 that can be displaced in the second direction along the Z axis as the "second axis" orthogonal to the Y axis due to the Coriolis force acting on the drive unit 44, and the drive unit 44 and the fixed unit. It has a mass portion 41 connecting the mass portion 41 and an elastic portion 43 connecting the mass portion 41 and the fixing portion 42. Further, the outer peripheral surface of the elastic portion 43 has a first main surface 431 and a second main surface 432 as a "main surface", and a first side surface 433 and a second side surface 434 as a "side surface".

Further, in the present embodiment, since it has an elastic portion 43 that is displaced by the vibration of the drive portion 44 and a support beam portion 48 that is not displaced relative to the vibration of the drive portion 44 and is displaced according to the collior force, the elastic portion is provided. There is a feature that the processing of 43 has little influence on the support beam portion 48. The support beam portion 48 may be any as long as it can be displaced in the Z-axis direction, and may be, for example, a twisting spring (torsion spring), a folded spring, or a thin plate-shaped spring in the Z direction.

According to the gyro sensor 1 according to the first embodiment described above, the distance T1 between the first portion 4301a as the outer beam portion and the fixed drive portion 45 as the structure, and the first portion as a plurality of beam portions. The first beam portion 4303 is provided when the distance T2 between the 4301a, 4301b, 4301c, and 4301d is T2 <T1. In other words, when the aperture ratio between the first portion 4301a and the fixed drive portion 45 is large, the first beam portion 4303 facing the first portion 4301a is provided on the fixed drive portion 45 side of the first portion 4301a. With this first beam portion 4303, the aperture ratio between the first portion 4301a and the fixed drive portion 45 can be reduced, and the opening ratios of the plurality of first portions 4301a, 4301b, 4301c, 4301d can be brought closer to each other. Can be done. As a result, even when deep etching (deep groove etching) with a depth D1 of 20 μm to 30 μm (20 μm ≦ D1 ≦ 30 μm) is performed, the variation in the cross-sectional shape due to the wraparound of the etching gas can be reduced, and the cross-sectional shape can be reduced. It is possible to reduce the variation in the resonance frequency of the elastic portion 43 including the plurality of first portions 4301a, 4301b, 4301c, 4301d caused by the variation in shape, and reduce the decrease in detection accuracy.

The interval T1 can be the distance between the first portion 4301a and the fixed drive portion 45 as a structure in one gyro sensor element 4, but is not limited to this, as described above. .. For the interval T1, for example, when etching is performed in a state where a plurality of gyro sensor elements 4 are arranged on a wafer, the portion of the gyro sensor element 4 located adjacent to the gyro sensor element 4 is regarded as a structure, and this structure and the first gyro sensor element 4 are regarded as a structure. It can be a distance (interval) between the 1st portion 4301a or a distance (interval) between the frame (support frame) and the 1st portion 4301a.

<Second Embodiment>
Next, a second embodiment of the physical quantity sensor will be described with reference to FIGS. 7 and 8. FIG. 7 is a plan view showing a schematic configuration of the gyro sensor according to the second embodiment of the physical quantity sensor. FIG. 8 is a plan view schematically showing a part (C portion) of the elastic portion shown in FIG. 7. In the following, the three axes orthogonal to each other will be described using the X-axis, the Y-axis, and the Z-axis as in the first embodiment. Further, in the following description, the differences from the first embodiment described above will be mainly described, and the description thereof will be omitted for the same matters.

As shown in FIGS. 7 and 8, the gyro sensor 1A according to the second embodiment is an angular velocity sensor capable of detecting an angular velocity around the X-axis, as in the first embodiment. As shown in FIG. 7, the gyro sensor 1A includes a gyro sensor element (angular velocity sensor element) 505 as a sensor element and a package (not shown) containing the gyro sensor element (angular velocity sensor element) 505. There is. Since the package is the same as that of the first embodiment described above, the description thereof will be omitted.

The gyro sensor element 505 includes two mass parts 501 and 502 arranged in the X-axis direction, two fixed detection parts 507 and 508, a plurality of fixed parts 510 and 540 including a support beam, and a plurality of connecting beams 520. It has an elastic portion 530 and a plurality of drive portions 551 and 552. The two mass parts 501 and 502 are configured symmetrically with respect to the + (plus) X-axis direction and the- (minus) X-axis direction, and have similar configurations to each other.

The mass portions 501 and 502 are connected to a fixing portion 510 including a support beam, a plurality of fixing portions 540 including the support beam, and a drive portion 551 and 552. Further, the mass portion 501 and the mass portion 502 are connected to each other by connecting beams 520 provided on the + Y-axis side and the −Y-axis side with the fixing portion 510 interposed therebetween. The mass portions 501 and 502 are integrally formed including a fixing portion 510 and 540, a connecting beam 520, a plurality of elastic portions 530, and a driving portion 551 and 552.

The fixing portion 510 including the support beam is arranged between the mass portion 501 and the mass portion 502, and supports the mass portion 501 and the mass portion 502 in a displaceable manner via the curved support beam. A plurality of fixing portions 540 including support beams are provided on the drive portion 551 side of the mass portion 501 and on the drive portion 552 side of the mass portion 502, respectively. The plurality of fixing portions 540 support the mass portion 501 and the mass portion 502 in a displaceable manner via a support beam.

The drive unit 551 is connected to the mass unit 501 via a support beam 550. The drive unit 552 is arranged on the side opposite to the drive unit 551 with respect to the mass units 501 and 502, and is connected to the mass unit 502 via a support beam 550. Each drive unit 551, 552 is connected to a portion of the mass units 501, 502 extending along the Y-axis direction. Each drive unit 551, 552 has a comb tooth shape including a trunk portion extending in the Y-axis direction along the mass portions 501 and 502 and a plurality of branch portions extending in the X-axis direction from the trunk portion. There is. Each drive unit 551 and 552 are arranged relative to a fixed drive unit (not shown).

The fixed detection units 507 and 508 (fixed detection electrodes) are provided so as to face each of the mass parts 501 and 502. The fixed detection units 507 and 508 are separated from the mass parts 501 and 502.

The plurality of elastic portions 530 are connected to both ends of the trunk portion of the drive portions 551 and 552, respectively. That is, in this embodiment, four elastic portions 530 are provided. The plurality of elastic portions 530 are connected to the mass portions 501 and 502 via the driving portions 551 and 552. The plurality of elastic portions 530 are configured so that the driving portions 551 and 552 can be displaced in the XY plane. Further, each elastic portion 530 forms a meandering shape in a plan view from the Z-axis direction, and constitutes a first portion 5301 as a plurality of beam portions extending along the Y-axis direction and a folded portion 533, and constitutes an X-axis. It has a second portion 5302 extending along the direction (see FIG. 8).

As shown in FIG. 8, the elastic portion 530 has a meandering shape in a plan view from the Z-axis direction. The elastic portion 530 includes a first portion 5301 as a plurality of long beam portions extending along the Y-axis direction, a second portion 5302 extending along the X-axis direction, and a third portion extending along the X-axis direction. It has a 5306, a fourth portion 5305 extending along the X-axis direction, and a plurality of first beam portions 5303 connected to each of the two first portions 5301. The interval T1 in FIG. 8 is the interval between the beam portion and the structure, and the interval T2 is the interval between the beam portion and the adjacent beam portion. Also, the first portion 5301 is longer than the second portion 5302. Further, the first portion 5301 means a portion separated by the broken lines QL11, QL12, QL13, and QL14 shown in the figure, respectively, as a general boundary line.

Further, the elastic portion 530 of the present embodiment includes two first portions 5301. The two first portions 5301 are arranged in parallel with a distance T2 from each other. One end of the first portion 5301 is connected to the trunk of the drive unit 551 via the third portion 5306. Here, the distance T1 between the first portion 5301 and the trunk of the drive unit 551 satisfies the relationship T2 <T1 with respect to the distance T2 between the first portion 5301 and the first portion 5301. One end of the other first portion 5301 is connected to the fixing portion 531 via the fourth portion 5305. The second portion 5302 connects the other end of one first portion 5301 opposite to the third portion 5306 and the other end of the other first portion 5301 opposite to the fourth portion 5305. The first portion 5301 connected in this way is folded back by the folded-back portion 533 including the second portion 5302 to form a meandering shape. The two first portions 5301 are preferably configured so that the width W1 in the direction orthogonal to the longitudinal direction (Y-axis direction) (X-axis direction) satisfies 0 <W1 ≦ 2 μm.

The first beam portion 5303 is arranged between the first portion 5301 and the trunk of the drive portion 551 as a structure. The first beam portion 5303 has a distance T3 from the first portion 5301 and is connected to the first portion 5301 via the connecting portion 5304. In this embodiment, two first beam portions 5303 are provided. The two first beam portions 5303 have a gap at a position facing the central portion in the longitudinal direction of the first portion 5301, and extend along the longitudinal direction of the first portion 5301. The first beam portion 5303 refers to a portion shown by hatching in the drawing as an approximate shape.

The first beam portion 5303 has a T3 / T2 ratio of 0.8, which is the ratio of the distance T3 between the first portion 5301 and the distance T2 between the first portion 5301 and the adjacent first portion 5301. It is preferable to arrange them so as to face the first portion 5301 so that <T3 / T2 <3.0. Further, it is more preferable that the distance T3 between the first beam portion 5303 and the first portion 5301 further satisfies 0.8 <T3 / T2 ≦ 2.0. Further, it is particularly preferable that the distance T3 between the first beam portion 5303 and the first portion 5301 satisfies 0.9 ≦ T3 / T2 ≦ 1.1.

Similar to the first embodiment, the first beam portion 5303 reduces variations in the cross-sectional shape of the first portion 5301 during dry etching such as the Bosch process used for forming the gyro sensor element 505. It is provided for the purpose. It should be noted that this variation in the cross-sectional shape is caused by the difference in the wraparound of the etching gas during dry etching caused by the density of the shape pattern of each part of the gyro sensor element 505, but is the same as in the first embodiment. Therefore, the detailed description here is omitted.

The first beam portion 5303 is not limited to the first portion 5301 side on the trunk side of the drive portion 551, but is located on the first portion 5301 located on the side opposite to the arrangement side (fixed portion 531 side) of the trunk portion of the drive unit 551. It may be provided. In this case, the first beam portion 5303 is arranged via the connecting portion 5304 so as to face the first portion 5301 on the fixed portion 531 side. Here, the arrangement pattern (arrangement configuration) such as the distance between the first portion 5301 and the first beam portion 5303 may be the same as that of the first beam portion 5303 on the trunk side of the drive unit 551 described above.

Further, the shape of the elastic portion 530 is not limited to the shape shown in the figure as long as it can be elastically deformed in a desired driving direction. Further, the elastic portion 530 of the present embodiment is connected to both ends of the trunk portion of the drive portion 551, but is not limited to this, and the mass portion 501 (drive portion 551) is displaceably supported with respect to the fixed portion 531. Any position can be used.

The configuration and advantages of the elastic portion 530 including the first portion 5301 including the first beam portion 5303 are the same as those in the first embodiment described above, and have been described in detail above. The description here is omitted.

According to the gyro sensor 1A according to the second embodiment described above, the variation in the cross-sectional shape due to the wraparound of the etching gas can be reduced as in the gyro sensor 1 according to the first embodiment, and the variation in the cross-sectional shape causes the variation in the cross-sectional shape. It is possible to reduce the variation in the resonance frequency of the elastic portion 530 including the plurality of first portions 5301 and reduce the decrease in detection accuracy.

The interval T1 can be the distance between the first portion 5301 and the trunk of the drive unit 551 as a structure in one gyro sensor element 505, as described above, but is limited to this. No. The interval T1 is set between the portion (structure) of the gyro sensor element 505 located adjacent to the gyro sensor element 505 and the first portion 5301, for example, when etching is performed in a state where a plurality of gyro sensor elements 505 are arranged on the wafer. It can be a distance (distance) between them, or a distance (interval) between a frame (support frame) and the first portion 5301.

<Third Embodiment>
Next, a third embodiment of the physical quantity sensor will be described with reference to FIGS. 9 and 10. FIG. 9 is a plan view showing a schematic configuration of the gyro sensor according to the third embodiment of the physical quantity sensor. FIG. 10 is a plan view schematically showing a part (F portion) of the elastic portion shown in FIG. 9. In the following, the three axes orthogonal to each other will be described using the X-axis, the Y-axis, and the Z-axis as in the first embodiment. Further, in the following description, the differences from the first embodiment described above will be mainly described, and the description thereof will be omitted for the same matters.

As shown in FIGS. 9 and 10, the gyro sensor 1B according to the third embodiment is an angular velocity sensor capable of detecting an angular velocity around the X-axis or the Y-axis. As shown in FIG. 9, the gyro sensor 1B includes a gyro sensor element (angular velocity sensor element) 605 as a sensor element and a package (not shown) containing the gyro sensor element (angular velocity sensor element) 605. There is. Since the same package as that of the first embodiment described above can be used, the description thereof will be omitted.

The gyro sensor element 605 has four element bodies 605a, 605b, 605c, 605d arranged in the X-axis and Y-axis directions, and four fixed detection units (not shown). As shown in FIG. 9, the four element bodies 605a, 605b, 605c, and 605d have + (plus) X, + Y-axis directions, + X,-(minus) Y-axis directions, -X, + Y-axis directions, and -X. , -Y axis directions and have similar configurations to each other.

Each element body 605a, 605b, 605c, 605d includes mass units 601a, 601b, 601c, 601d. Each element body 605a, 605b, 605c, 605d has a support beam portion 640 connecting the element body 605a and the element body 605b, a support beam portion 640 connecting the element body 605c and the element body 605d, and two support beam portions 640. And the connecting beam portion 620 connected to the fixing portion 510, and is supported by the fixing portion 510 in a displaceable manner.

Hereinafter, the configuration will be described with the element body 605a as a representative example. The element body 605a includes an outer frame portion 613a, 614a, and an outer frame portion 613a, 614a, which connect the mass portion 601a, the end portion of the mass portion 601a on the + X-axis direction side, and the end portion on the −X-axis direction side in an arc shape. It has a drive unit 610 connected to the drive unit 610, a fixed drive electrode unit 618 facing the drive unit 610, and an elastic unit 630 that displaceably supports the mass unit 601a with respect to the fixed unit 633. The mass part 601a, the outer frame part 613a, 614a, the driving part 610, and the elastic part 630 constituting the element body 605a are connected to the support beam part 640 connecting the element bodies 605a, 605b, 605c, 605d to the fixing part 510. It is integrally formed including the portion 620.

The outer shape of the mass portion 601a is a circular central portion and the + X-axis direction and −X from the central portion along the X-axis direction in a plan view (hereinafter, simply referred to as “planar view”) viewed from the Z-axis direction. It has a shape including a general fan-shaped extending portion extending in both axial directions.

The outer frame portion 614a connects the outer edge portion of the mass portion 601a on the + X-axis direction side and the outer edge portion on the −X-axis direction side in an arc shape in the + Y-axis direction. The outer frame portion 613a connects the outer edge portion of the mass portion 601a on the + X-axis direction side and the outer edge portion on the −X-axis direction side in an arc shape in the −Y-axis direction.

The drive unit 610 is provided with two configurations each between the outer frame portion 613a and the mass portion 601a and between the outer frame portion 614a and the mass portion 601a. The drive unit 610 includes a plurality of trunk portions 611 connecting the outer frame portions 613a and 614a and the mass portion 601a, and a plurality of branch portions 612 extending in an arc shape on both sides from the trunk portion 611. The plurality of branch portions 612 are arranged in an arc shape substantially concentric with the outer edge of the central portion of the mass portion 601a.

The fixed drive electrode portion 618 is an arcuate comb having a substantially concentric circle with the outer edge of the central portion of the mass portion 601a so as to face each of the branch portions 612 arranged on both sides of the trunk portion 611 of the drive portion 610. They are arranged in a tooth pattern.

The plurality of elastic portions 630 are connected to the four corner portions of the mass portions 601a, 601b, 601c, and 601d. That is, in this embodiment, elastic portions 630 are provided at 16 locations. Hereinafter, the configuration will be described with the element body 605a as a representative example. One end of the plurality of elastic portions 630 is connected to the fixed portion 633, and the other end is connected to the mass portion 601a. The plurality of elastic portions 630 are configured so that the mass portion 601a can be displaced. As shown in FIG. 10, each elastic portion 630 has a meandering shape in a plan view, and constitutes a first portion 6301 as a plurality of beam portions extending along the X-axis direction and a folded portion 631 and constitutes a Y-axis. It has a second portion 6302 extending along the direction.

As shown in FIG. 10, the elastic portion 630 has a first portion 6301 as a plurality of long beam portions extending along the X-axis direction, a second portion 6302 extending along the Y-axis direction, and a Y-axis direction. It has a third portion 6306 extending along the line and a plurality of first beam portions 6303a, 6303b connected to each of the two first portions 6301. The interval T1 in FIG. 10 is the interval between the beam portion (first portion 6301) and the structure (mass portion 601a), and the interval T2 is the interval T2 between the beam portion (first portion 6301) and the adjacent beam portion (first portion). It is an interval with 6301). Also, the first portion 6301 is longer than the second portion 6302. Further, the first portion 6301 means a portion separated by the broken lines QL21, QL22, QL23, QL24, QL25, QL26, and QL27, respectively, as a general boundary line. The second portion 6302 constitutes a so-called folded portion 631 in which two ends of the first portion 6301 and the adjacent first portion 6301 are connected and folded back. The plurality of first portions 6301 are folded back by the folded-back portion 631 including the second portion 6302 to form a meandering shape. Further, one end of the elastic portion 630 is connected to the mass portion 601a via the third portion 6306, and the other end thereof is connected to the fixed portion 633.

Further, the elastic portion 630 of the present embodiment includes a plurality of first portions 6301. The plurality of first portions 6301 are arranged so as to be parallel to each other with an interval T2. The first portion 6301 on the mass portion 601a side (−Y axis direction side) has an end opposite to the folded portion 631 connected to the mass portion 601a via the third portion 6306. Here, the distance T1 between the first portion 6301 and the mass portion 601a as a structure satisfies the relationship of T2 <T1 with respect to the distance T2 between the first portion 6301 and the first portion 6301. There is. The end of the first portion 6301 on the fixed portion 633 side (+ Y-axis direction side) opposite to the folded portion 631 is connected to the fixed portion 633. The second portion 6302 connects the ends of the adjacent first portions 6301 to each other to form the folded-back portion 631. The plurality of first portions 6301 connected in this way are folded back by the folded-back portion 631 including the second portion 6302 to form a meandering shape. The plurality of first portions 6301 are preferably configured so that the width W1 in the direction orthogonal to the longitudinal direction (X-axis direction) (Y-axis direction) satisfies 0 <W1 ≦ 2 (μm).

The first beam portion 6303a is arranged between the first portion 6301 on the mass portion 601a side (−Y axis direction side) and the mass portion 601a as a structure. The first beam portion 6303a has an interval T3 between the first beam portion 6301 and the first beam portion 6301, and is connected to the first portion 6301 via the connecting portion 6304a. The first beam portion 6303a extends along the longitudinal direction of the first portion 6301.

The first beam portion 6303a has a T3 / T2 ratio of 0.8 <T3 / T2 <3. It is preferable to arrange it so as to face the first portion 6301 so that it becomes 0. Further, it is more preferable that the distance T3 between the first beam portion 6303a and the first portion 6301 further satisfies 0.8 <T3 / T2 ≦ 2.0. Further, it is particularly preferable that the distance T3 between the first beam portion 6303a and the first portion 6301 satisfies 0.9 ≦ T3 / T2 ≦ 1.1.

Similar to the first embodiment, the first beam portion 6303a reduces variations in the cross-sectional shape of the first portion 6301 during dry etching such as the Bosch process used for forming the gyro sensor element 605. It is provided for the purpose. It should be noted that this variation in the cross-sectional shape is caused by the difference in the wraparound of the etching gas during dry etching caused by the density of the shape pattern of each part of the gyro sensor element 605, but is the same as in the first embodiment. Therefore, the detailed description here is omitted.

The first beam portion 6303a is not limited to the first portion 6301 side on the mass portion 601a side, but may be provided on the first portion 6301 located on the opposite side (fixed portion 633 side) to the arrangement side of the mass portion 601a. .. In this case, as shown in FIG. 10, the first beam portion 6303b is arranged via the connecting portion 6304b so as to face the first portion 6301 on the fixing portion 633 side. Here, the arrangement pattern (arrangement configuration) such as the distance between the first portion 6301 and the first beam portion 6303b may be the same as that of the first beam portion 6303a on the mass portion 601a side described above.

Further, the shape of the elastic portion 630 is not limited to the shape shown in the figure as long as it can be elastically deformed in a desired driving direction. Further, the elastic portions 630 of the present embodiment are connected to both sides of the mass portion 601a, but the present invention is not limited to this, and the mass portion 601a is fixed to, for example, both sides of the mass portion 601a in the X-axis direction. Any position may be used as long as it can be displaceably supported with respect to 633.

The configuration and advantages of the elastic portion 630 including the first portion 6301 including the first beam portions 6303a and 6303b are the same as those in the first embodiment described above, and are described in detail above. Therefore, the explanation here is omitted.

According to the gyro sensor 1B according to the third embodiment described above, the variation in the cross-sectional shape due to the wraparound of the etching gas can be reduced as in the gyro sensor 1 according to the first embodiment, and the variation in the cross-sectional shape causes the variation in the cross-sectional shape. It is possible to reduce the variation in the resonance frequency of the elastic portion 630 including the plurality of first portions 6301, and to reduce the deterioration of the detection accuracy.

The interval T1 can be the distance between the first portion 6301 and the mass portion 601a as a structure in one gyro sensor element 605, as described above, but is not limited to this. The interval T1 is, for example, the distance between the structure of the gyro sensor element 605 located adjacent to the gyro sensor element 605 and the first portion 6301 when etching is performed in a state where a plurality of gyro sensor elements 605 are arranged on the wafer. It can be (spacing) or the distance (spacing) between the frame (support frame) and the first portion 6301.

(Composite sensor)
Next, with reference to FIG. 11, a configuration example of a composite sensor including any of the above-mentioned gyro sensors 1, 1A and 1B will be described. FIG. 11 is a functional block diagram showing a schematic configuration of the composite sensor.

The composite sensor 900 shown in FIG. 11 includes, for example, a 3-axis angular velocity sensor and a 3-axis acceleration sensor that detect the posture and behavior (inertial momentum) of a moving body (attached device) such as an automobile or a robot. It functions as a so-called 6-axis motion sensor.

As shown in FIG. 11, the composite sensor 900 includes three angular velocity sensors 920x, 920y, 920z capable of detecting the angular velocity of one axis, and an acceleration sensor 950 capable of detecting the acceleration of three axes. The angular velocity sensors 920x, 920y, and 920z are not particularly limited, and any of the above-mentioned gyro sensors 1, 1A, and 1B using the Coriolis force can be used. The angular velocity sensors 920x, 920y, and 920z are sensors that reduce the decrease in detection accuracy, respectively, as in the above-described embodiment, and can perform stable and highly accurate angular velocity detection. The accelerometer 950 may also be equipped with an independent sensor for measuring acceleration in each of the three axes.

According to such a composite sensor 900, an angular velocity sensor 920x, 920y, 920z to which any of the gyro sensors 1, 1A and 1B according to the above-described embodiment is applied, and an acceleration sensor 950 capable of detecting acceleration of three axes. The composite sensor 900 can be easily configured by the above method, and for example, angular velocity data and acceleration data can be easily acquired.

<Inertial measurement unit>
Next, an inertial measurement unit (IMU) will be described with reference to FIGS. 12 and 13. FIG. 12 is an exploded perspective view showing a schematic configuration of the inertial measurement unit. FIG. 13 is a perspective view showing an arrangement example of the inertial sensor element of the inertial measurement unit.

The inertial measurement unit 2000 (IMU) shown in FIG. 12 is a device that detects the posture and behavior (inertial momentum) of a moving body (mounted device) such as an automobile or a robot. The inertial measurement unit 2000 functions as a so-called 6-axis motion sensor including a 3-axis acceleration sensor and a 3-axis angular velocity sensor.

The inertial measurement unit 2000 is a rectangular parallelepiped having a substantially square plane shape. Further, screw holes 2110 as fixing portions are formed in the vicinity of two vertices located in the diagonal direction of the square. The inertial measurement unit 2000 can be fixed to the mounted surface of a mounted body such as an automobile by passing two screws through the two screw holes 2110. By selecting parts and changing the design, it is possible to reduce the size to a size that can be mounted on a smartphone or a digital camera, for example.

The inertial measurement unit 2000 has an outer case 2100, a joining member 2200, and a sensor module 2300, and has a configuration in which the sensor module 2300 is inserted by interposing the joining member 2200 inside the outer case 2100. There is. Further, the sensor module 2300 has an inner case 2310 and a substrate 2320.

The outer shape of the outer case 2100 is a rectangular parallelepiped whose plane shape is substantially square, similar to the overall shape of the inertial measurement unit 2000, and screw holes 2110 are formed in the vicinity of two vertices located in the diagonal direction of the square. There is. Further, the outer case 2100 has a box shape, and the sensor module 2300 is housed inside the outer case 2100.

The inner case 2310 is a member that supports the substrate 2320, and has a shape that fits inside the outer case 2100. Further, the inner case 2310 is formed with a recess 2311 for preventing contact with the substrate 2320 and an opening 2312 for exposing the connector 2330 described later. Such an inner case 2310 is joined to the outer case 2100 via a joining member 2200 (for example, a packing impregnated with an adhesive). Further, the substrate 2320 is bonded to the lower surface of the inner case 2310 via an adhesive.

As shown in FIG. 13, on the upper surface of the substrate 2320, there are a connector 2330, an angular velocity sensor 2340z for detecting an angular velocity around the Z axis, an acceleration sensor 2350 for detecting acceleration in each axis of the X axis, the Y axis, and the Z axis. Is implemented. Further, on the side surface of the substrate 2320, an angular velocity sensor 2340x for detecting the angular velocity around the X axis and an angular velocity sensor 2340y for detecting the angular velocity around the Y axis are mounted. The angular velocity sensors 2340z, 2340x, and 2340y are not particularly limited, and any of the above-mentioned gyro sensors 1, 1A, and 1B using the Coriolis force can be used. Further, the acceleration sensor 2350 is not particularly limited, and a capacitance type acceleration sensor or the like can be used.

Further, a control IC 2360 is mounted on the lower surface of the substrate 2320. The control IC 2360 is an MCU (Micro Controller Unit), which has a built-in storage unit including a non-volatile memory, an A / D converter, and the like, and controls each unit of the inertial measurement unit 2000. The storage unit stores a program that defines the order and contents for detecting acceleration and angular velocity, a program that digitizes detection data and incorporates it into packet data, and accompanying data. In addition, a plurality of other electronic components are mounted on the substrate 2320.

The inertial measurement unit 2000 has been described above. Such an inertial measurement unit 2000 includes an angular velocity sensor 2340z, 2340x, 2340y and an acceleration sensor 2350, and a control IC 2360 (control circuit) that controls the drive of each of these sensors 2340z, 2340x, 2340y, 2350. As a result, the effect of the gyro sensor 1 described above can be enjoyed, and a highly reliable inertial measurement unit 2000 can be obtained.

<Portable electronic device>
Next, a portable electronic device using any of the gyro sensors 1, 1A and 1B will be described in detail with reference to FIGS. 14 and 15. Hereinafter, as an example of a portable electronic device, a wristwatch-type activity meter (active tracker) will be shown, and a configuration to which the gyro sensor 1 is applied will be described.

As shown in FIG. 14, the wristwatch-type activity meter (active tracker) wrist device 1000 is attached to a part (subject) such as a user's wrist by a band 1032, 1037 or the like, and displays a digital display unit 150. It is possible to prepare and wirelessly communicate. The gyro sensor 1 according to the above-described embodiment is incorporated in the wrist device 1000 together with a sensor for measuring acceleration and the like as an angular velocity sensor 114 (see FIG. 15) for measuring an angular velocity.

The wrist device 1000 includes a case 1030 in which at least the angular velocity sensor 114 (see FIG. 15) is housed, a processing unit 100 (see FIG. 15) housed in the case 1030 and processing output data from the angular velocity sensor 114, and a case. It includes a display unit 150 housed in the 1030 and a translucent cover 1071 that closes the opening of the case 1030. A bezel 1078 is provided on the outside of the case 1030 of the translucent cover 1071 of the case 1030. A plurality of operation buttons 1080 and 1081 are provided on the side surface of the case 1030. Hereinafter, a more detailed description will be given with reference to FIG.

The acceleration sensor 113 detects accelerations in the three-axis directions that intersect each other (ideally orthogonal to each other), and outputs a signal (acceleration signal) according to the magnitude and direction of the detected three-axis acceleration. Further, the angular velocity sensor 114 detects each angular velocity in the triaxial directions intersecting each other (ideally orthogonal to each other), and outputs a signal (angular velocity signal) according to the magnitude and direction of the detected triaxial angular velocity. do.

In the liquid crystal display (LCD) constituting the display unit 150, for example, position information using a GPS sensor 110 or a geomagnetic sensor 111, a movement amount or acceleration sensor 113, an angular velocity sensor 114, or the like is used according to various detection modes. Exercise information such as the amount of exercise that has been performed, biological information such as the pulse rate using the pulse sensor 115, or time information such as the current time is displayed. It is also possible to display the environmental temperature using the temperature sensor 116.

The communication unit 170 performs various controls for establishing communication between a user terminal and an information terminal (not shown). The communication unit 170 is, for example, Bluetooth (registered trademark) (BTLE: including Bluetooth Low Energy), Wi-Fi (registered trademark) (Wireless Fidelity), Zigbee (registered trademark), NFC (Near field communication), ANT + (registered). It includes a transmitter / receiver compatible with short-range wireless communication standards such as (trademark) and a connector compatible with communication bus standards such as USB (Universal Serial Bus).

The processing unit 100 (processor) is composed of, for example, an MPU (Micro Processing Unit), a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), or the like. The processing unit 100 executes various processes based on the program stored in the storage unit 140 and the signal input from the operation unit 120 (for example, the operation buttons 1080 and 1081). The processing by the processing unit 100 includes data processing for each output signal of the GPS sensor 110, the geomagnetic sensor 111, the pressure sensor 112, the acceleration sensor 113, the angular velocity sensor 114, the pulse sensor 115, the temperature sensor 116, and the timekeeping unit 130, and the display unit 150. Display processing to display an image on the sensor, sound output processing to output sound to the sound output unit 160, communication processing to communicate with an information terminal via the communication unit 170, power control processing to supply power from the battery 180 to each unit, etc. Is included.

Such a wrist device 1000 can have at least the following functions.
1. 1. Distance: The total distance (movement distance) and movement trajectory from the start of measurement are measured by the high-precision GPS function.
2. 2. Pace: Displays the current running pace from the pace distance measurement value.
3. 3. Average speed: Calculates and displays the average speed from the start of driving to the present.
4. Elevation: The GPS function measures and displays the altitude.
5. Stride: Measures and displays stride length even in tunnels where GPS radio waves do not reach.
6. Pitch: Measures and displays the number of steps per minute.
7. Heart rate: The heart rate is measured and displayed by the pulse sensor.
8. Gradient: Measures and displays the slope of the ground during training and trail running in the mountains.
9. Auto lap: Automatically measures laps when running a preset fixed distance or a certain period of time.
10. Exercise calories burned: Shows calories burned.
11. Steps: Displays the total number of steps since the start of exercise.

The wrist device 1000 can be widely applied to a running watch, a runner's watch, a runner's watch compatible with multi-sports such as dual sports and a triathlon, an outdoor watch, and a satellite positioning system, for example, a GPS watch equipped with GPS.

Further, although the above description has been made using GPS (Global Positioning System) as the satellite positioning system, another global navigation satellite system (GNSS: Global Navigation Satellite System) may be used. For example, one or more of satellite positioning systems such as EGNOS (European Geostationary-Satellite Navigation Overlay Service), QZSS (Quasi Zenith Satellite System), GLONASS (GLONASS (GLObal NAvigation Satellite System), GALIEO, BeiDou (BeiDou Navigation Satellite System), etc. May be used. In addition, at least one of the satellite positioning systems uses a geostationary satellite navigation augmentation system (SBAS: Satellite-based Augmentation System) such as WAAS (Wide Area Augmentation System) and EGNOS (European Geostationary-Satellite Navigation Overlay Service). May be good.

Since such a portable electronic device includes a gyro sensor 1 and a processing unit 100, it has excellent reliability.

<Electronic equipment>
Next, an electronic device using any of the gyro sensors 1, 1A and 1B will be described in detail with reference to FIGS. 16 to 18. In the following description, a configuration to which the gyro sensor 1 is applied will be illustrated and described.

First, a mobile personal computer, which is an example of an electronic device, will be described with reference to FIG. FIG. 16 is a perspective view schematically showing the configuration of a mobile personal computer which is an example of an electronic device.

In this figure, the personal computer 1100 is composed of a main body portion 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display unit 1108, and the display unit 1106 rotates with respect to the main body portion 1104 via a hinge structure portion. It is movably supported. Such a personal computer 1100 has a built-in gyro sensor 1 that functions as an angular velocity sensor, and the control unit 1110 can perform control such as attitude control based on the detection data of the gyro sensor 1.

FIG. 17 is a perspective view schematically showing the configuration of a smartphone (mobile phone) which is an example of an electronic device.

In this figure, the smartphone 1200 incorporates the gyro sensor 1 described above. The detection data (angular velocity data) detected by the gyro sensor 1 is transmitted to the control unit 1201 of the smartphone 1200. The control unit 1201 includes a CPU (Central Processing Unit), recognizes the posture and behavior of the smartphone 1200 from the received detection data, and changes the display image displayed on the display unit 1208. , You can make a warning sound, a sound effect, or drive a vibration motor to vibrate the main body. In other words, it is possible to perform motion sensing of the smartphone 1200 and change the display content, generate sound, vibration, or the like from the measured posture and behavior. In particular, when running a game application, you can experience a sense of reality that is close to reality.

FIG. 18 is a perspective view showing the configuration of a digital steel camera which is an example of an electronic device. It should be noted that this figure also briefly shows the connection with an external device.

In this figure, a display unit 1310 is provided on the back surface of the case (body) 1302 of the digital still camera 1300, and is configured to display based on an image pickup signal by a CCD. The display unit 1310 displays a subject electronically. It also functions as a finder to display as an image. Further, on the front side (back side in the drawing) of the case 1302, a light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided.

When the photographer confirms the subject image displayed on the display unit 1310 and presses the shutter button 1306, the image pickup signal of the CCD at that time is transferred and stored in the memory 1308. Further, in the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. Then, as shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312, and a personal computer 1440 is connected to the input / output terminal 1314 for data communication, respectively, as needed. Further, the image pickup signal stored in the memory 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation. Such a digital still camera 1300 has a built-in gyro sensor 1 that functions as an angular velocity sensor, and the control unit 1316 can perform control such as camera shake correction based on the detection data of the gyro sensor 1.

Since such an electronic device includes a gyro sensor 1 and control units 1110, 1201, 1316, it has excellent reliability.

In addition to the personal computer of FIG. 16, the smartphone (mobile phone) of FIG. 17, and the digital still camera of FIG. 18, the electronic device provided with the gyro sensor 1 includes, for example, a tablet terminal, a clock, and an inkjet ejection device (for example,). Inkjet printer), laptop personal computer, TV, video camera, video tape recorder, car navigation device, pager, electronic notebook (including communication function), electronic dictionary, calculator, electronic game equipment, word processor, workstation, TV Telephone, security TV monitor, electronic binoculars, POS terminal, medical equipment (for example, electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish finder, various measuring devices, instruments Classes (for example, vehicle, aircraft, ship instruments), flight simulators, seismometers, pedometers, tilt meters, vibration meters that measure the vibration of hard disks, attitude control devices for flying objects such as robots and drones, and automatic driving of automobiles. It can be applied to control equipment used for inertial navigation.

<Mobile>
Next, a moving body using any of the gyro sensors 1, 1A and 1B is shown in FIG. 19 and will be described in detail. In the following description, a configuration to which the gyro sensor 1 is applied will be illustrated and described. FIG. 19 is a perspective view showing the configuration of an automobile which is an example of a moving body.

As shown in FIG. 19, the automobile 1500 has a built-in gyro sensor 1, and for example, the posture of the vehicle body 1501 can be detected by the gyro sensor 1. The detection signal of the gyro sensor 1 is supplied to the vehicle body attitude control device 1502 as an attitude control unit for controlling the attitude of the vehicle body, and the vehicle body attitude control device 1502 detects the attitude of the vehicle body 1501 based on the signal, and the detection result. Depending on the situation, the hardness of the suspension can be controlled, and the brakes of the individual wheels 1503 can be controlled. In addition, the gyro sensor 1 also includes a keyless entry system, an immobilizer, a car navigation system, a car air conditioner, an anti-lock braking system (ABS), an airbag, a tire pressure monitoring system (TPMS), and a tire pressure monitoring system (TPMS). It can be widely applied to an engine control system (engine system), an inertial navigation control device for automatic driving, and an electronic control unit (ECU) such as a battery monitor of a hybrid vehicle or an electric vehicle.

In addition to the above examples, the gyro sensor 1 applied to a moving body is, for example, posture control of a bipedal walking robot or a train, remote control of a radiocon airplane, a radiocon helicopter, and a drone, or an autonomous type. Used for attitude control of flying objects, attitude control of agricultural machinery (agricultural machinery) or construction machinery (construction machinery), control of rockets, artificial satellites, ships, AGVs (unmanned transport vehicles), bipedal walking robots, etc. Can be done. As described above, the gyro sensor 1 and each control unit (not shown) are incorporated in the realization of attitude control of various moving objects.

Since such a moving body includes a gyro sensor 1 and a control unit (for example, a vehicle body attitude control device 1502 as an attitude control unit), such a moving body has excellent reliability.

Although the physical quantity sensor, the composite sensor, the inertial measurement unit, the portable electronic device, the electronic device, and the moving body have been described above based on the illustrated embodiment, the present invention is not limited to this, and the configuration of each part is not limited thereto. Can be replaced with any configuration having a similar function. Further, any other constituent may be added to the present invention.

Further, in the above-described embodiment, the X-axis, the Y-axis, and the Z-axis are orthogonal to each other, but if they intersect each other, the present invention is not limited to this, and for example, the X-axis is relative to the normal direction of the YZ plane. The Y-axis may be slightly tilted with respect to the normal direction of the XY plane, or the Z-axis may be slightly tilted with respect to the normal direction of the XY plane. The term "slightly" means a range in which the physical quantity sensor (gyro sensor 1) can exert its effect, and the specific tilt angle (numerical value) differs depending on the configuration and the like.

1,1A, 1B ... Gyro sensor as a physical quantity sensor, 2 ... Substrate, 3 ... Lid member, 4 ... Gyro sensor element (angular velocity sensor element) as a sensor element, 10 ... Package, 21 ... Recessed part, 22 ... Protruding part, 23 ... upper surface, 31 ... concave, 33 ... lower surface, 40, 40a, 40b ... element body, 41 ... mass part, 42 ... fixed part, 43 ... elastic part, 44 ... drive part, 45 ... fixed drive part as a structure , 46 ... Fixed drive unit, 48 ... Support beam part, 49, 49a, 49b ... Fixed detection unit, 212 ... Bottom surface, 430 ... Folded part, 431 ... First main surface, 432 ... Second main surface, 471 ... Detection unit , 472 ... detector, 473 ... frame, 900 ... composite sensor, 1000 ... wrist device as portable electronic device, 1100 ... personal computer as electronic device, 1200 ... smartphone as electronic device, 1300 ... digital as electronic device Steel camera, 1500 ... Automobile as a moving body, 2000 ... Inertivity measuring unit, 4301a, 4301b, 4301c, 4301d ... First part as a beam part, 4302 ... Second part as a beam part, 4303 ... First beam part, 4304 ... Connection part, T1 ... Space between the first part and the fixed drive part, T2 ... Space between the first parts next to each other, T3 ... Space between the first part and the first beam part, W1 ... Width of the first part , Q ... The gap between the first beam portion and the first beam portion, QL1, QL2, QL3, QL4, QL5, QL6, QL7 ... A broken line indicating the boundary of the first portion.

Claims (16)

When the three axes orthogonal to each other are the X-axis, Y-axis, and Z-axis,
With the board
A sensor element supported on the upper surface of the substrate located on the positive side of the Z axis and detecting a change in capacitance, and a sensor element.
Including
The sensor element is
The mass part arranged on the upper surface of the substrate and the mass part
A drive unit arranged on the upper surface of the substrate and
An elastic portion arranged on the upper surface of the substrate and connected to the driving portion and the mass portion, and
Including
The mass part is displaced based on the drive of the drive part,
The elastic portion includes an inner beam portion and an outer beam portion arranged in parallel with each other.
The outer beam portion is arranged between the inner beam portion and the drive portion.
The elastic portion includes a first beam portion parallel to the outer beam portion.
In a plan view from the Z-axis direction along the Z-axis, the first beam portion is arranged between the outer beam portion and the drive portion.
The distance between the outer beam portion and the drive portion is T1.
When the distance between the inner beam portion and the outer beam portion is T2,
T2 <T1
Meet, physical quantity sensor. In claim 1,
When the distance between the outer beam portion and the first beam portion is T3,
0.8 <T3 / T2 <3.0
Meet, physical quantity sensor. In claim 2,
0.8 <T3 / T2≤2.0
Meet, physical quantity sensor. In claim 3,
0.9 ≤ T3 / T2 ≤ 1.1
Meet, physical quantity sensor. In any one of claims 1 to 4,
T1 ≤ 10 μm
Meet, physical quantity sensor. In any one of claims 1 to 5,
The first beam portion is a physical quantity sensor connected to the outer beam portion via a connecting portion. In claim 6,
The connecting portion is a physical quantity sensor connected to an intermediate portion of the first beam portion. In claim 7 ,
A physical quantity sensor in which the first beam portion and the connecting portion are integrally T-shaped in a plan view from the Z-axis direction. In any one of claims 1 to 8 ,
The sensor element is a physical quantity sensor including a fixed portion fixed to the upper surface of the substrate. In any one of claims 1 to 9,
A physical quantity sensor having a meandering shape in the elastic portion in a plan view from the Z-axis direction. In any one of claims 1 to 10,
A physical quantity sensor in which the inner beam portion and the outer beam portion are formed by dry etching. In any one of claims 1 to 11.
The upper surface of the substrate is provided with a recess.
The recess is a physical quantity sensor that faces the mass part, the driving part, and the elastic part through a gap. In any one of claims 1 to 12,
The sensor element is a physical quantity sensor including a detection unit that detects an angular velocity based on a change in capacitance. The physical quantity sensor according to any one of claims 1 to 13.
A control unit that controls the physical quantity sensor and
Inertial measurement unit, including. The physical quantity sensor according to any one of claims 1 to 13.
A control unit that controls based on the detection signal output from the physical quantity sensor, and
Including electronic devices. The physical quantity sensor according to any one of claims 1 to 13.
An attitude control unit that controls the attitude based on the detection signal output from the physical quantity sensor, and
Including mobiles.

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