Patent Description:
There are sensors such as gyro sensors. It is desired to improve the characteristics of the sensor. <CIT> discloses a rotational rate gyroscope.

According to a first aspect of the invention, a gyro sensor according to claim <NUM> is provided.

Various embodiments are described below with reference to the accompanying drawings.

The drawings are schematic and conceptual; and the relationships between the thickness and width of portions, the proportions of sizes among portions, etc., are not necessarily the same as the actual values. The dimensions and proportions may be illustrated differently among drawings, even for identical portions.

In the specification and drawings, components similar to those described previously in an antecedent drawing are marked with like reference numerals, and a detailed description is omitted as appropriate.

<FIG> and <FIG> are schematic plan views illustrating the sensor according to the first embodiment.

<FIG> is the schematic cross-sectional view illustrating the sensor according to the first embodiment. <FIG> is a sectional view taken along line A1-A2 of <FIG>. As shown in <FIG>, a sensor <NUM> according to the embodiment includes a base body <NUM>, a first fixed portion <NUM>, a movable portion <NUM>, a connecting portion <NUM>, and a first fixed electrode <NUM>. In <FIG>, the connecting portion <NUM> and the first fixed electrode <NUM> are illustrated in broken lines and their exact shapes are omitted.

The base body <NUM> may include, for example, a silicon substrate. The first fixed portion <NUM> is fixed to the base body <NUM>. At least a part of the first fixed portion <NUM> is conductive.

A direction from the base body <NUM> to the first fixed portion <NUM> is defined as a first direction D1. The first direction D1 is a Z-axis direction. One direction perpendicular to the Z-axis direction is defined as an X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is defined as a Y-axis direction.

The movable portion <NUM> is provided around the first fixed portion <NUM> in a first plane crossing the first direction D1. The first plane is, for example, the X-Y plane. The movable portion <NUM> is an annular shape centered on the first fixed portion <NUM>. The movable portion <NUM> includes an outer edge portion 10o and an inner edge portion 10i. The inner edge portion 10i is located between the first fixed portion <NUM> and the outer edge portion 10o. For example, the outer edge portion 10o has a circular shape centered on the first fixed portion <NUM>. For example, the inner edge portion 10i has a circular shape centered on the first fixed portion <NUM>. The movable portion <NUM> is conductive. At least one of the outer edge portion 10o and the inner edge portion 10i may be polygonal.

The movable portion <NUM> includes a first partial region <NUM>, a second partial region <NUM>, and a third partial region <NUM>. <FIG> illustrates the first partial region <NUM>, the second partial region <NUM>, and the third partial region <NUM>. The first partial region <NUM> is an annular shape centered on the first fixed portion <NUM>. The first partial region <NUM> includes an outer edge portion 10o. The second partial region <NUM> is provided between the first partial region <NUM> and the first fixed portion <NUM>. The second partial region <NUM> is an annular shape centered on the first fixed portion <NUM>. The second partial region <NUM> includes the inner edge portion 10i.

The third partial region <NUM> is provided between the first partial region <NUM> and the second partial region <NUM>. The third partial region <NUM> is an annular shape centered on the first fixed portion <NUM>. The third partial region <NUM> includes a first movable portion electrode 13E. The third partial region <NUM> is a region where the electrodes are provided. The first partial region <NUM> is an outer region. The second partial region <NUM> is an inner region.

The connecting portion <NUM> is provided between the first fixed portion <NUM> and the second partial region <NUM>. The connecting portion <NUM> connects the second partial region <NUM> to the first fixed portion <NUM>. The connecting portion <NUM> is conductive.

As shown in <FIG>, a first gap g1 is provided between the base body <NUM> and the movable portion <NUM> and between the base body <NUM> and the connecting portion <NUM>. The connecting portion <NUM> is, for example, a spring portion. The connecting portion <NUM> may have a meander structure.

The first fixed electrode <NUM> is fixed to the base body <NUM>. The first fixed electrode <NUM> faces the first movable portion electrode 13E. For example, the first fixed electrode <NUM> faces the first movable portion electrode 13E in the first plane (for example, in the X-Y plane).

For example, the first movable portion electrode 13E is in contact with the inner end of the first partial region <NUM>. For example, the first movable portion electrode 13E is in contact with the outer end of the third partial region <NUM>. As will be described later, a second fixed electrode <NUM> is further provided. As shown in <FIG>, the second fixed electrode <NUM> faces the second movable portion electrode 13F. The second movable portion electrode 13F is in contact with the outer end of the second partial region <NUM>. The second movable portion electrode 13F is in contact with the inner end of the third partial region <NUM>.

As will be described later, the third partial region <NUM> includes a first fixed electrode hole 13EH (see <FIG>). The first fixed electrode <NUM> passes through the first fixed electrode hole 13EH. For example, the first fixed electrode hole 13EH is in contact with the inner end of the first partial region <NUM>. As will be described later, the third partial region <NUM> includes a second fixed electrode hole 13FH (see <FIG>). The second fixed electrode <NUM> passes through the second fixed electrode hole 13FH. For example, the second fixed electrode hole 3FH is in contact with the outer end of the second partial region <NUM>.

A circle can be defined centering on the first fixed portion <NUM> and passing through the outer end of the first fixed electrode <NUM>. This circle corresponds to the inner edge of the first partial region <NUM>. A circle can be defined centered on the first fixed portion <NUM> and passing through the inner end of the second fixed electrode <NUM>. This circle corresponds to the outer edge of the second partial region <NUM>.

For example, the sensor <NUM> may include a controller <NUM>. The controller <NUM> may be provided separately from the sensor <NUM>. The controller <NUM> can apply a voltage between the movable portion <NUM> and the first fixed electrode <NUM>. For example, the electrode 21E is provided on the first fixed portion <NUM>. The controller <NUM> is electrically connected to the movable portion <NUM> via the electrode 21E, the first fixed portion <NUM>, and the connecting portion <NUM>. The controller <NUM> can vibrate the movable portion <NUM> by applying an AC voltage between the movable portion <NUM> and the first fixed electrode <NUM>. As a result, the movable portion <NUM> can vibrate along the X-Y plane, for example. The vibration is, for example, an in-plane translational vibration. In one example, translational vibrations along the X-axis direction occur.

In the embodiment, for example, when a force (angular velocity) is applied to a movable portion that vibrates in the X-axis direction in the initial state, the vibration state of the movable portion <NUM> changes. For example, in the movable portion <NUM>, vibration including a component in the Y-axis direction occurs. For example, the movable portion <NUM> vibrates in a direction different from the initial state according to the applied angular velocity. The change in vibration state is based on, for example, the Coriolis force. By detecting the change in the vibration state, the force (the angular velocity) can be detected.

The movable portion <NUM> has a resonance mode different from the in-plane translation. For example, an in-plane rotation resonance, an out-of-plane twist resonance, and an out-of-plane translational resonance exist in the movable portion <NUM>. The resonance of in-plane rotation is, for example, a resonance of rotation in the X-Y plane centered on the first fixed portion <NUM>. The resonance of the out-of-plane twist is, for example, a resonance including a component of rotation out of the X-Y plane about the X-axis direction or the like. The out-of-plane translational resonance is, for example, a resonance along the Z-axis direction. These resonances are lower order resonances than that in the in-plane translations.

The detection result detected by the sensor <NUM> is affected by these low-order resonances. For example, by keeping the target in-plane translational resonance frequency and restraining dropping of the low-order resonances, the influence of the low-order resonance can be suppressed. As a result, the target force (the acceleration) can be detected with high accuracy.

The area of the second partial region <NUM> being inner is not less than the area of the first partial region <NUM> being outer. For example, the volume of the second partial region <NUM> is not less than the volume of the first partial region <NUM>. For example, the mass of the second partial region <NUM> is not less than the mass of the first partial region <NUM>. As a result, the dropping of the low-order resonance frequency can be restrained. The influence of low-order resonance can be suppressed. According to the embodiment, it is possible to provide a sensor whose characteristics can be improved. An example of resonance characteristics will be described later.

As shown in <FIG>, a direction passing through the first fixed portion <NUM> and along the first plane (the X-Y plane) is defined as a radial direction Dr. A length of the first partial region <NUM> along the radial direction Dr is defined as a first length L1. A length of the second partial region <NUM> along the radial direction Dr is defined as a second length L2. The second length L2 is not less than the first length L1. With such a configuration, the dropping of the frequency of low-order resonance can be restrained. The influence of low-order resonance can be suppressed.

In the embodiment, the mass of the movable portion <NUM> is concentrated on the inner portion of the movable portion <NUM>. As a result, the dropping of the low-order resonance frequency can be restrained. The influence of low-order resonance can be suppressed.

Hereinafter, an example of the simulation result regarding a change in the resonance frequency when the masses of the first partial region <NUM> and the second partial region <NUM> are changed will be described.

<FIG> are graphs illustrating the characteristics of the sensor.

The horizontal axis of these figures is a mass ratio R1. A mass of the first partial region <NUM> is defined as a first mass M1. A mass of the second partial region <NUM> is defined as a second mass M2. The mass ratio R1 is a ratio (M2 / M1) of the second mass M2 to the first mass M1. The vertical axis of <FIG> is a resonance frequency f1 of the in-plane rotation. The vertical axis of <FIG> is a resonance frequency f2 of the out-of-plane twist. There are two different types of resonance in the out-of-plane twist resonance. The resonance frequencies of these two types of resonance are close to each other. The resonance frequency f2 is a resonance frequency relating to one of these two types of resonance (relatively low frequency resonance). The characteristics of the resonance frequency for another one of the two types of resonance related to the out-of-plane twist (relatively high frequency resonance) are substantially the same as the characteristics of the resonance frequency f2, and thus the illustration is omitted. The vertical axis of <FIG> is a resonance frequency f3 of the out-of-plane translation. The vertical axis of <FIG> is a resonance frequency f4 of the in-plane translation. In the in-plane translational resonance, there are two different types of resonance. The frequencies of these two types of resonance are close to each other. The resonance frequency f4 is a resonance frequency relating to one of these two types of resonance (relatively low frequency resonance). The characteristics of the resonance frequency for another one of the two types of resonance related to in-plane translation (relatively high frequency resonance) are substantially the same as the characteristics of the resonance frequency f4, and thus the illustration is omitted. In this simulation, the mass ratio R1 is changed while keeping the in-plane translation frequency f4 constant. In <FIG>, the mass of the movable portion <NUM> is about <NUM>. In this example, the width (for example, the diameter) of the movable portion <NUM> along the X-axis direction is <NUM>.

As shown in <FIG>, when the mass ratio R1 becomes low, the resonance frequency f1 of the in-plane rotation, the resonance frequency f2 of the out-of-plane twist, and the resonance frequency f3 of the out-of-plane translation decrease. When the mass ratio R1 is <NUM> or more, these resonance frequencies are maintained. The mass ratio R1 may be <NUM> or more. The resonance frequency is kept more stably.

The horizontal axis of these figures is the mass ratio R1. The vertical axis of <FIG> is the resonance frequency f1 of the in-plane rotation. The vertical axis of <FIG> is the resonance frequency f2 of the out-of-plane twist. The vertical axis of <FIG> is the resonance frequency f3 of the out-of-plane translation. The vertical axis of <FIG> is the resonance frequency f4 of the in-plane translation. In this simulation, the mass ratio R1 is changed while keeping the frequency of the in-plane translation constant. In the example of <FIG>, the mass of the movable portion <NUM> is about <NUM>. In this example, the width (for example, the diameter) of the movable portion <NUM> along the X-axis direction is <NUM>. Also in <FIG>, the characteristic of the resonance frequency with respect to another one of the types of resonances relating to the out-of-plane twist is omitted. Also in <FIG>, the characteristic of the resonance frequency relating to another of the two types relating to the in-plane translation is omitted.

As shown in <FIG>, when the mass ratio R1 becomes low, the resonance frequency f1 of the in-plane rotation, the resonance frequency f2 of the out-of-plane twist, and the resonance frequency f3 of the out-of-plane translation decrease. When the mass ratio R1 is <NUM> or more, these resonance frequencies are maintained. When the mass ratio R1 is <NUM> or more, these resonance frequencies are kept more stably.

In the embodiment, the mass ratio R1 is <NUM> or more. As a result, the resonance frequency f1 of the in-plane rotation, the resonance frequency f2 of the out-of-plane twist, and the resonance frequency f3 of the out-of-plane translation are maintained. The mass ratio R1 may be, for example, <NUM> or more. The mass ratio R1 may be, for example, <NUM> or more. The mass ratio R1 may be, for example, <NUM> or more.

For example, the specific density of the first partial region <NUM> may be substantially the same as the specific gravity of the second partial region <NUM>. In this case, the mass ratio R1 corresponds to a volume ratio. The volume ratio is a ratio of the volume of the second partial region <NUM> to the volume of the first partial region <NUM>. In the embodiment, the volume ratio is <NUM> or more. The volume ratio may be, for example, <NUM> or more. The volume ratio may be, for example, <NUM> or more. The volume ratio may be, for example, <NUM> or more.

For example, the thickness of the first partial region <NUM> may be substantially the same as the thickness of the second partial region <NUM>. The thickness is a length along the Z-axis direction. In this case, the mass ratio R1 corresponds to an area ratio. The area ratio is a ratio of the area of the second partial region <NUM> to the area of the first partial region <NUM>. In the embodiment, the area ratio is <NUM> or more. The area ratio may be, for example, <NUM> or more. The area ratio may be, for example, <NUM> or more. The area ratio may be, for example, <NUM> or more.

The horizontal axis of these figures is a length ratio R2. The length ratio R2 is a ratio (L2 / L1) of the second length L2 to the first length L1. The vertical axis of <FIG> is the resonance frequency f1 of the in-plane rotation. The vertical axis of <FIG> is the resonance frequency f2 of the out-of-plane twist. The vertical axis of <FIG> is the resonance frequency f3 of the out-of-plane translation. The vertical axis of <FIG> is the resonance frequency f4 of the in-plane translation. Also in <FIG>, the characteristic of the resonance frequency with respect to another one of the types of resonances relating to the out-of-plane twist is omitted. Also in <FIG>, the characteristic of the resonance frequency relating to another of the two types relating to the in-plane translation is omitted. In the example of <FIG>, the mass of the movable portion <NUM> is about <NUM>. In this example, the width (for example, the diameter) of the movable portion <NUM> along the X-axis direction is <NUM>.

As shown in <FIG>, when the length ratio R2 becomes low, the resonance frequency f1 of the in-plane rotation, the resonance frequency f2 of the out-of-plane twist, and the resonance frequency f3 of the out-of-plane translation decrease. When the length ratio R2 is <NUM> or more, these resonance frequencies are maintained. When the length ratio R2 is <NUM> or more, these resonance frequencies are maintained more stably.

The horizontal axis of these figures is the length ratio R2. The vertical axis of <FIG> is the resonance frequency f1 of the in-plane rotation. The vertical axis of <FIG> is the resonance frequency f2 of the out-of-plane twist. The vertical axis of <FIG> is the resonance frequency f3 of the out-of-plane translation. The vertical axis of <FIG> is the resonance frequency f4 of the in-plane translation. In this simulation, the length ratio R2 is changed while keeping the frequency of the in-plane translation constant. In the example of <FIG>, the mass of the movable portion <NUM> is about <NUM>. In this example, the width (for example, the diameter) of the movable portion <NUM> along the X-axis direction is <NUM>. Also in <FIG>, the characteristic of the resonance frequency with respect to another one of the types of resonances relating to the out-of-plane twist is omitted. Also in <FIG>, the characteristic of the resonance frequency relating to another of the two types relating to the in-plane translation is omitted.

In the embodiment, the length ratio R2 is <NUM> or more. The length ratio R2 may be <NUM> or more. The length ratio R2 may be <NUM> or more. As a result, the resonance frequency f1 of the in-plane rotation, the resonance frequency f2 of the out-of-plane twist, and the resonance frequency f3 of the out-of-plane translation are maintained.

In the embodiment, the second length L2 is not less than the first length L1. In the embodiment, the second length L2 is preferably twice or more the first length L1. The second length L2 may be <NUM> times or more the first length L1. The frequency of the low-order resonance can be effectively maintained. The influence of low-order resonance can be effectively suppressed.

<FIG> are schematic plan views illustrating a part of the sensor according to the first embodiment.

These figures exemplify the first fixed electrode <NUM> and the first movable portion electrode 13E in an enlarged manner. As shown in <FIG>, the third partial region <NUM> includes the first fixed electrode hole 13EH. The first fixed electrode hole 13EH extends along the first direction D1. The first movable portion electrode 13E is provided in the first fixed electrode hole 13EH. The first fixed electrode <NUM> passes through the first fixed electrode hole 13EH.

In this example, the first movable portion electrode 13E and the first fixed electrode <NUM> are comb-shaped. As shown in <FIG>, the first movable portion electrode 13E is one of the first comb tooth electrode pair 20T. The first fixed electrode <NUM> is the other side of the first comb tooth electrode pair 20T. The first movable portion electrode 13E includes a base portion 10b and a plurality of protruding portions 10p. The plurality of protruding portions 10p are connected to the base portion h10b. The first fixed electrode <NUM> includes a base portion 41b and a plurality of protruding portions 41p. The plurality of protruding portions 41p are connected to the base portion 41b. At least a part of one of the plurality of protruding portions 41p is provided between one of the plurality of protruding portions 10p and another one of the plurality of protruding portions 10p. At least a part of one the plurality of protruding portions 10p is provided between one of the plurality of protruding portions 41p and another one of the plurality of protruding portions 41p.

As shown in <FIG>, in this example, the sensor <NUM> further includes a second fixed electrode <NUM>. The second fixed electrode <NUM> is fixed to the base body <NUM>. The third partial region <NUM> includes a second movable portion electrode 13F. In this example, the second fixed electrode <NUM> is provided between the second partial region <NUM> and the first fixed electrode <NUM>.

<FIG> is a schematic plan view illustrating a part of the sensor according to the first embodiment.

<FIG> illustrates the second fixed electrode <NUM> and the second movable portion electrode 13F. The second fixed electrode <NUM> faces the second movable portion electrode 13F. The third partial region <NUM> includes a second fixed electrode hole 13FH. The second movable portion electrode 13F is provided in the second fixed electrode hole 13FH. The second fixed electrode hole 13FH extends in the first direction D1. The second fixed electrode <NUM> passes through the second fixed electrode hole 13FH. The second fixed electrode <NUM> faces the second movable portion electrode 13F in the first plane (in the X-Y plane). A voltage may be applied between the second fixed electrode <NUM> and the second movable portion electrode 13F. As will be described later, the second fixed electrode <NUM> and the second movable portion electrode 13F may be a pair of comb tooth electrodes.

As shown in <FIG>, a plurality of first movable portion electrodes 13E and a plurality of first fixed electrodes <NUM> may be provided. The plurality of first movable portion electrodes 13E are arranged in a circle centered on the first fixed portion <NUM>. The plurality of first fixed electrodes <NUM> are arranged in a circle centered on the first fixed portion <NUM>.

As shown in <FIG>, the sensor <NUM> may further include a third fixed electrode <NUM>. In this example, a plurality of third fixed electrodes <NUM> are provided. The plurality of third fixed electrodes <NUM> are fixed to the base body <NUM>. The third partial region <NUM> includes a plurality of third movable portion electrodes <NUM>. For example, the plurality of third fixed electrodes <NUM> and the plurality of first fixed electrodes <NUM> are alternately arranged along a circle centered on the first fixed portion <NUM>.

<FIG> illustrates one of a plurality of third fixed electrodes <NUM> and one of a plurality of third movable portion electrodes <NUM>. One of the plurality of third fixed electrodes <NUM> faces one of the plurality of third movable portion electrodes <NUM>. The third partial region <NUM> includes the third fixed electrode hole 13GH. The third movable portion electrode <NUM> is provided in the third fixed electrode hole 13GH. The third fixed electrode hole 13GH extends in the first direction D1. The third fixed electrode <NUM> passes through the third fixed electrode hole 13GH. The third fixed electrode <NUM> faces the third movable portion electrode <NUM> in the first plane (in the X-Y plane). A voltage may be applied between the third fixed electrode <NUM> and the third movable portion electrode <NUM>.

As shown in <FIG>, the sensor <NUM> may further include a second fixed portion <NUM>. The second fixed portion <NUM> is fixed to the base body <NUM>.

<FIG> illustrates the second fixed portion <NUM>. The third partial region <NUM> includes the second fixed portion hole <NUM>. The second fixed portion <NUM> passes through the second fixed portion hole <NUM>. The second fixed portion <NUM> functions as, for example, a stopper.

In this example, the second fixed portion <NUM> includes a protruding portion 22p. By providing the protruding portion 22p, the area where the second fixed portion <NUM> comes into contact with the movable portion <NUM> becomes smaller when the movable portion <NUM> is largely displaced. Damage to the movable portion <NUM> is suppressed. Such a protruding portion may be provided on the movable portion <NUM>.

<FIG> is a schematic plan view illustrating the sensor according to the second embodiment.

As shown in <FIG>, in a sensor <NUM> according to the embodiment, the movable portion <NUM> includes a plurality of holes. Except for this, the configuration of the sensor <NUM> may be the same as that of the sensor <NUM>. That is, the sensor <NUM> also includes the base body <NUM>, the first fixed portion <NUM>, the movable portion <NUM>, the connecting portion <NUM>, and the first fixed electrode <NUM>. The movable portion <NUM> includes the first partial region <NUM>, the second partial region <NUM>, and the third partial region <NUM>.

The first partial region <NUM> includes a plurality of first holes <NUM>. The plurality of first holes <NUM> have a first width W1 and a first density. The first width W1 is a length of one of the plurality of first holes <NUM> along the first radial direction. The first radial direction passes through the first fixed portion <NUM> and is along the first plane (the X-Y plane). For example, the first radial direction may be the X-axis direction. The first density is a density in the first plane (the X-Y plane) of the plurality of first holes <NUM>.

The second partial region <NUM> includes a plurality of second holes <NUM>. The plurality of second holes <NUM> have at least one of a second width W2 smaller than the first width W1 and a second density lower than the first density. The second width W2 is a length of one of the plurality of second holes <NUM> along a second radial direction. The second radial direction passes through the first fixed portion <NUM> and is along the first plane (the X-Y plane). For example, the second radial direction may be the X-axis direction. The second density is a density in the first plane (the X-Y plane) of the plurality of second holes <NUM>.

By providing such a plurality of first holes <NUM>, the mass of the first partial region <NUM> tends to be smaller than the mass of the second partial region <NUM>. The frequency of the low-order resonance can be effectively maintained. The influence of the low-order resonance can be effectively suppressed.

For example, when forming the movable portion <NUM> and the connecting portion <NUM>, the etchant passes through the plurality of first holes <NUM> and the plurality of second holes <NUM>. As a result, the first gap g1 (see <FIG>) can be formed.

The plurality of first holes <NUM> and the plurality of second holes <NUM> may be provided in the movable portion <NUM> of the sensor <NUM>. When these holes are provided in the movable portion <NUM> of the sensor <NUM>, the widths or densities of these holes may be the same.

<FIG> is a schematic plan view illustrating a part of the sensor according to the embodiment.

<FIG> is an enlarged example of the movable portion <NUM>. As shown in <FIG>, the plurality of first holes <NUM> may be arcuate. For example, the plurality of first holes <NUM> have an arc shape centered on the first fixed portion <NUM>. The plurality of second holes <NUM> may be arcuate. For example, the plurality of second holes <NUM> have an arc shape centered on the first fixed portion <NUM>.

The plurality of holes may be provided in the third partial region <NUM>. In the example shown in <FIG>, the second fixed electrode <NUM> and the second movable portion electrode 13F are a pair of comb tooth electrodes.

In the embodiment, another fixed electrode may be provided around the movable portion <NUM> in the X-Y plane. Another fixed electrode faces the movable portion <NUM> (e.g., the first partial region <NUM>). Another fixed electrode and the first partial region <NUM> are a pair of parallel plate electrodes. A plurality of different fixed electrodes may be arranged around the movable portion <NUM> along the circumferential direction.

According to the embodiment, it is possible to provide a sensor whose characteristics can be improved.

In the specification of the application, "perpendicular" and "parallel" refer to not only strictly perpendicular and strictly parallel but also include, for example, the fluctuation due to manufacturing processes, etc. It is sufficient to be substantially perpendicular and substantially parallel.

Hereinabove, exemplary embodiments of the invention are described with reference to specific examples. However, the embodiments of the invention are not limited to these specific examples. For example, one skilled in the art may similarly practice the invention by appropriately selecting specific configurations of components included in sensors such as base bodies, fixed portions, moving portions, connecting portions, controllers, etc., from known art. Such practice is included in the scope of the invention to the extent that similar effects thereto are obtained.

Further, any two or more components of the specific examples may be combined within the extent of technical feasibility and are included in the scope of the invention to the extent that the purport of the invention is included.

Claim 1:
A gyro sensor comprising:
a base body (<NUM>);
a first fixed portion (<NUM>) fixed to the base body (<NUM>);
a movable portion (<NUM>) provided around the first fixed portion in a first plane crossing a first direction (D1) from the base body to the first fixed portion, the movable portion including:
a first partial region (<NUM>) being annular, the first partial region being centered on the first fixed portion,
a second partial region (<NUM>) being annular, the second partial region being provided between the first partial region and the first fixed portion and centered on the first fixed portion, and
a third partial region (<NUM>) being annular, the third partial region being provided between the first partial region and the second partial region and centered on the first fixed portion, the third partial region including a first movable portion electrode (13E);
wherein the first partial region is defined between an outer edge portion (10o) of the movable portion (<NUM>) and a first circle that is defined centering on the first fixed portion (<NUM>) and passing through an outer end of a first fixed electrode (<NUM>);
wherein the second partial region is defined between an inner edge portion (10i) of the movable portion (<NUM>) and an second circle that is defined centering on the first fixed portion (<NUM>) and passing through an inner end of a second fixed electrode (<NUM>);
wherein the third partial region is defined between the first circle and the inner end of the second fixed electrode (<NUM>);
a connecting portion (<NUM>) provided between the first fixed portion and the second partial region, the connecting portion connecting the second partial region to the first fixed portion, a first gap (g1) being provided between the base body and the movable portion, and between the base body and the connecting portion; and
the first fixed electrode (<NUM>) fixed to the base body, the first electrode facing the first movable portion electrode (13E),
characterized in that:
a second area of the second partial region on the first plane being not less than a first area of the first partial region on the first plane.