JPH10239347A - Motion sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a mass part large at an acceleration-detecting part thereby improving detection accuracy for an acceleration, by forming an angular velocity sensor and an acceleration sensor at a semiconductor substrate so that the mass part of the acceleration sensor is like a rectangular frame surrounding the angular velocity sensor. SOLUTION: When an acceleration is applied in a positive direction, a left inertial force is applied to a mass part 1 relative to a common substrate 9 of the motion sensor. As a result, a rectangular wave-like mass part-supporting body 21 or mass part-supporting body 24 is deformed, and the mass part 1 is moved leftward. When the mass part 1 is moved leftward, a movable comb- like electrode is moved leftward at an X-direction acceleration detection part 31 and an X-direction acceleration detection part 33, whereby a variable capacitance composed of the movable comb-like electrode and a fixed comb-like electrode is increased or decreased. It can be so recognized on the basis of the increase or decrease of the variable capacitances of both X-direction acceleration detection parts 31, 33 that the acceleration is applied in the positive X direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motion sensor and, more particularly, to a motion sensor for monitoring a motion state by detecting a biaxial angular velocity and a triaxial acceleration.

[0002]

2. Description of the Related Art A motion sensor for monitoring a motion state by detecting a biaxial angular velocity and a triaxial acceleration will be described. First, a vibration gyro for detecting an angular velocity will be described with reference to FIGS. zy indicates a vibration gyro,
It comprises a motion sensor common substrate 9 made of a semiconductor.
The vibrating body 10 of the vibrating gyroscope zy has a hexagonal column shape in cross section, and is integrally formed with the frame 30 via the support 80. A driving piezoelectric element 20 is formed at the center of the upper surface of the vibrating body 10. The driving piezoelectric element 20 is formed by directly sputtering or depositing a piezoelectric material on the center of the upper surface of the vibrating body 10. A detecting piezoelectric element 3a and a detecting piezoelectric element 3b are formed at the center of the lower slope of the vibrating body 10. The detection piezoelectric element 3a and the detection piezoelectric element 3b are also formed by directly sputtering or vapor-depositing a piezoelectric material on the center of the lower slope of the vibrating body 10, similarly to the driving piezoelectric element 20. On each of these piezoelectric elements, a piezoelectric element electrode film is formed. The electrodes of the driving piezoelectric element 20 are connected to the oscillation circuit 11, and the electrodes of the detecting piezoelectric element 3 a and the detecting piezoelectric element 3 b are connected to the detecting circuit 12. The surface of the vibrating body 10 made of a semiconductor on which these piezoelectric elements are formed constitutes the other electrode of each of these piezoelectric elements. The oscillation frequency of the oscillation circuit 11 generates a drive signal having the same frequency as the natural frequency in the driving direction of the vibrating body 10. This driving signal is applied to the driving piezoelectric element 20, whereby the vibrating body 10 bends and vibrates in the vertical direction in FIG. The vibrating body 10 also bends and vibrates in the horizontal direction in FIG. 4 corresponding to the magnitude and frequency of the distortion in the vertical direction, and the piezoelectric element 3a for detection and the piezoelectric element 3 for detection.
b generate a voltage output corresponding to this bending vibration.

When an angular velocity about the axis of the vibrating body, which is an input shaft, is input while the vibrating body 10 is vibrating vertically, a Coriolis force is generated in the left-right direction, and the vibrating body 10 is driven in the left-right direction. Force acts. The vibrating body 1 is driven by this Coriolis force.
The output voltage of the detecting piezoelectric element 3 changes from the point where the vibration direction of 0 is shifted. In this case, while the output of one of the detecting piezoelectric elements 3a and the detecting piezoelectric elements 3b increases, the output of the other detecting piezoelectric element decreases. An input angular velocity can be obtained by detecting the amount of change in the output of one of the detection piezoelectric elements 3 or the amount of change in the differential output between the two outputs by the detection circuit 12.

An acceleration sensor for detecting acceleration will be described with reference to FIGS. 4 and 6. FIG. 6 is a diagram showing a cross section passing through the beam-like structure 50 of the acceleration sensor. 30 is mass part 1
Is a frame part surrounding. The mass 1 and the frame 30 are connected by a beam-like structure 50. The mass 1, the frame 30, and the beam-like structure 50 are formed by forming a recess 60 in the motion sensor common substrate 9. The beam-like structure 50 is completed by processing the lower side to form a cutout 70 and reducing its thickness. With such a configuration, the beam-like structure 50 can be easily bent up and down with respect to the frame 30 by the inertial force acting on the mass 1. R ₁ to R ₄ are piezoresistive units. Piezoresistive portion R ₁ is formed across the beam-like structure 4 surface and the frame 30 surface. Piezoresistive portion R ₄ are also formed across the beam-like structure 4 surface and the frame 30 surface. Piezoresistive portions R ₂ and piezoresistive portion R ₃ is generally in the form of a beam-like structure 50 surface.

[0005] The acceleration sensor described above has a piezoresistive section R ₁
It can be detected measuring acceleration by to form a bridge circuit each other are opposed to the piezoresistive portion R ₂ and piezoresistive portion R ₃ together to each other facing the piezoresistive portion R _4. That is, when acceleration in the direction of the arrow is input to the acceleration sensor, an inertial force in the direction of the arrow acts on the mass unit 4 due to this, and as a result, the mass unit 1 is displaced in the direction of the arrow and the beam-shaped structure is formed. The part 50 is bent downward. When the beam-like structure 50 is brought into the bent downward pulling force is applied to the piezoresistive portion R ₁ and the piezoresistive portion R ₄ are formed on the upper surface. Piezoresistive portion R ₁ and the piezoresistive portion R
The resistance value of these resistance parts changes due to the tensile force applied to ₄ . As a result, the balance of the bridge circuit is lost and an output voltage proportional to the change in the resistance value is obtained. This change in the resistance value is proportional to the input acceleration.

[0006]

By the way, the motion sensor shown in FIG. 4 is merely a structure in which an angular velocity sensor and an acceleration sensor are simply arranged on a semiconductor substrate such as silicon in a planar manner and arranged separately. In general, the angular velocity sensor and the acceleration sensor are configured to be large in size, so that the measurement accuracy performance is improved. However, the motion sensor in FIG. 4 uses a semiconductor substrate area of a certain size sufficiently effectively. It is difficult to say that the measurement accuracy performance is improved by forming the angular velocity sensor and the acceleration sensor.

The present invention provides a motion sensor that solves the above-mentioned problem.

[0008]

[Means for Solving the Problems]

Claim 1: A motion sensor comprising an angular velocity sensor and an acceleration sensor formed on a semiconductor substrate, wherein the mass part 1 constituting the acceleration sensor ac is of a quadrangular frame shape formed surrounding the angular velocity sensor zy. Was configured. Claim 2: In the motion sensor according to claim 1, the quadrangular frame-shaped mass portion 1 is held in a state of being floated from the motion sensor common substrate 9 by the mass portion support body 21 which is configured to extend in a rectangular wave shape. A motion sensor was constructed.

Further, in the motion sensor according to the present invention, the mass support 21 is formed so as to protrude slightly upward from the motion sensor common substrate 9.
1, 213, 232, 231 constituted a motion sensor. Claim 4: The motion sensor according to any one of claims 2 and 3, wherein the mass support 21 is coupled to each side of the quadrangular frame of the mass 1. Was configured.

Here, claim 5 is the motion sensor according to any one of claims 1 to 4, wherein the acceleration detection units 31 to 34 are formed in the quadrangular frame of the mass unit 1. The motion sensor formed in the above was constructed. Claim 6: The motion sensor according to claim 5, wherein the acceleration detecting section is a variable capacitance type acceleration detecting section.

According to a seventh aspect of the present invention, in the motion sensor according to the sixth aspect, the electrode surface forming the capacitance of the acceleration detector is set parallel to the z direction. Further, in the motion sensor according to the present invention, the electrodes forming the capacitance are formed by projecting from the plurality of movable comb electrodes 342 extending from the mass portion 1 and the motion sensor common substrate 9. A motion sensor comprising a plurality of movable comb-shaped electrodes 345 extended from the acceleration detection base 343 is constructed.

[0012] In the motion sensor according to the present invention, an acceleration detecting section whose electrode surface is set parallel to the x-direction and the z-direction, and the electrode surface is connected to the y-direction and the z-direction.
A motion sensor having an acceleration detection unit set parallel to the direction is configured. Claim 10: In the motion sensor as set forth in claim 9, a pair of acceleration detectors whose electrode surfaces are set parallel to the x direction and the z direction, and the electrode surfaces are set parallel to the y direction and the z direction. A motion sensor having a pair of acceleration detectors is provided.

[0013] Further, in the motion sensor according to any one of claims 8 to 10, each one of the one comb electrode and the other comb electrode adjacent to both surfaces thereof may be provided. , And a motion sensor was constructed in which one of the comb-shaped electrodes was displaced in the z-direction with respect to the other and was set to face the other. Further, in the motion sensor according to any one of claims 1 to 11, the angular velocity sensor j
y constituted a motion sensor which is a variable capacitance type angular velocity sensor.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing an embodiment of a motion sensor including an angular velocity sensor and an acceleration sensor as viewed from above. 2A and 2B are enlarged perspective views of a part of the acceleration sensor in FIG. 1, wherein FIG. 2A is an enlarged perspective view of a part of an acceleration detection unit, and FIG. A perspective view showing an enlarged view of the vicinity of the mass connecting portion,
(C) is an enlarged perspective view showing the vicinity of a base connecting portion of the mass part support. FIG. 3 shows a perspective view of the two-axis angular velocity sensor.

(Configuration of Acceleration Sensor) First, an acceleration sensor according to an embodiment of the motion sensor will be described with reference to FIG. The embodiment of the motion sensor of the present invention is divided into two parts by a dashed line, and the outside divided by the dashed line shows the area of the acceleration sensor ac. The area inside the one-dot chain line indicates the area of the two-axis angular velocity sensor zy. The acceleration sensor ac has a mass 1 and a rectangular wave-shaped mass support 21.
24 to 24, and x-direction acceleration detection units 31 and 33 and y-direction acceleration detection units 32 and 34. The above-described motion sensors are sequentially formed by applying photolithography technology to the surface of the motion sensor common substrate 9 made of a semiconductor, and all except the insulating film 7 are made of a semiconductor or a conductor.

As described above, although the outer edge of the mass portion 1 is square, the inner region thereof has a square frame-shaped mass due to the formation of the biaxial angular velocity sensor zy and the four acceleration detecting portions 31 to 34. The unit is configured. Next, the acceleration detection unit of the acceleration sensor will be described with reference to FIG. Reference numerals 31 to 34 denote four acceleration detectors, 31 and 33 are x-direction acceleration detectors, and 32
And 34 are y-direction acceleration detectors. Although the position and direction of the acceleration detection unit are different from each other,
Since each configuration itself is the same, the y-direction acceleration detection unit 34 will be described as a representative. Note that, as will be described later, the mass unit 1 is supported in a state in which it floats slightly without contacting the motion sensor common substrate 9. Reference numeral 341 denotes a square hole of the acceleration detection unit formed in the frame of the mass unit 1. A plurality of movable comb electrodes 342 are formed on each of the side surfaces in the y direction of the square hole 341 so as to extend in parallel with each other. The movable comb-shaped electrode 342 is formed to extend in a slightly floating state without contacting the motion sensor common substrate 9. Reference numeral 343 denotes an acceleration detection base, which is formed to project upward from the motion sensor common substrate 9 via an insulating layer. A support pole 344 is formed on the acceleration detecting portion base 343 so as to extend in the y direction on each of the side surfaces in the x direction. A plurality of fixed comb electrodes 345 are formed on each of the side surfaces in the y direction of the support pole 344 and the acceleration detection base 343 in parallel with each other. The plurality of movable comb electrodes 342 and the plurality of fixed comb electrodes 345 are alternately interleaved and arranged to face each other as shown in the figure, and both comb waves eventually constitute a variable capacitance. ing.

The mutual spacing between the plurality of movable comb electrodes 342 and the plurality of fixed comb electrodes 345 will be described.
The intervals between the plurality of movable comb electrodes 342 are set equal, and the intervals between the fixed comb electrodes 345 are set equal. Then, the intervals between each one of the one comb electrodes and the other comb electrodes adjacent to both sides thereof are arranged differently. That is, in the y-direction acceleration detecting section 34, the movable comb electrode 342 is largely displaced downward or upward from the intermediate position with respect to the fixed comb electrode 345, and one of the fixed comb electrodes 345 is displaced.
Are disposed very close to the other fixed comb wave electrode 345. In the x-direction acceleration detector 31 and the x-direction acceleration detector 33, the movable comb electrode 34
2 is largely displaced leftward or rightward from the intermediate position with respect to the fixed comb electrode 345, is located very close to one fixed comb electrode 345, and is largely separated from the other fixed comb electrode 345. . The movable comb electrode 342 and the fixed comb electrode 34
By setting the mutual intervals of the electrodes 5 in this manner, the electrostatic capacitance between the movable comb electrodes 342 increases as the movable comb electrodes 342 further approach the fixed comb electrodes 345, but the movable comb electrodes 342 are separated from the fixed comb electrodes 345. And the capacitance between the two electrodes decreases.

Furthermore, regarding the overlap in the z direction, which is the vertical direction, between the movable comb electrode 342 and the fixed comb electrode 345, the movable comb electrode 342 is positioned above the fixed comb electrode 345 in the z direction. It is displaced downward and is set to face.
That is, when the movable comb electrode 342 is displaced in the positive z direction and is set to face the fixed comb electrode 345, when the movable comb electrode 342 is displaced in the positive z direction by acceleration, the capacitance between the two electrodes becomes While decreasing, displacement in the negative z-direction increases the capacitance between the two electrodes. When the movable comb electrode 342 is displaced in the negative z direction with respect to the fixed comb electrode 345 and is set to face the fixed comb electrode 345, when the movable comb electrode 342 is displaced in the negative z direction by acceleration, the capacitance between both electrodes decreases. While the positive z
The displacement in the direction increases the capacitance between the two electrodes.

Referring to FIG. 2B, a description will be given of the rectangular wave mass support of the acceleration sensor. Mass support 2
Focusing on 1, reference numerals 211 and 212 denote mass bases, which are formed to slightly protrude from the motion sensor common substrate 9. The mass support 21 extending in the form of a rectangular wave is supported by the base coupling portions 213 and 2 in a state where the mass support 21 slightly floats without contacting the motion sensor common substrate 9.
14 and attached to these mass bases.
The mass support 21 is further coupled to the mass 1 via a mass coupling 215 at an intermediate portion thereof. After all,
The mass unit 1 floats from the motion sensor common board 9 by the mass unit base 211 and the mass unit base 212 via the mass unit coupling unit 215, the mass unit support 21, the base coupling unit 213, and the base coupling unit 214. It will be kept in the state where it was done. Mass support 22 to mass support 24 also participate in retaining mass 1.

(Operation of Acceleration Sensor) Here, the operation of the acceleration sensor will be described. Assuming that acceleration is applied in the positive direction of x, a leftward inertial force is applied to the mass unit 1 with respect to the motion sensor common substrate 9. When a leftward inertial force is applied to the mass unit 1, the rectangular wave-shaped mass unit supports 21 to 24 are deformed, and the mass unit 1 is deformed.
Is displaced to the left. When the mass unit 1 is displaced to the left, the movable comb electrode 342 is displaced to the left in the x-direction acceleration detection unit 31 and the x-direction acceleration detection unit 33, so that the movable comb electrode 342 and the fixed comb electrode 345 displace. The resulting variable capacitance increases or decreases.
It can be recognized that acceleration has been applied in the positive x direction based on the increase or decrease in the variable capacitance of both the x-direction acceleration detectors.

Assuming that acceleration is applied in the negative direction of x, a rightward inertial force is applied to the mass unit 1 with respect to the motion sensor common substrate 9. When a rightward inertial force is applied to the mass 1, the rectangular wave-shaped mass support 21 to 24 are deformed, and the mass 1 is displaced rightward. When the mass unit 1 is displaced rightward, x
In the directional acceleration detecting section 31 and the x-directional acceleration detecting section 33, the movable comb electrode 342 is displaced rightward, so that the variable capacitance composed of the movable comb electrode 342 and the fixed comb electrode 345 increases or decreases. It can be recognized that acceleration has been applied in the negative x direction based on the increase or decrease in the variable capacitance of both the x-direction acceleration detectors.

Similarly, when acceleration is applied in the y-positive direction, the increase or decrease of the variable capacitance in both the y-direction acceleration detection unit 32 and the y-direction acceleration detection unit 34 is detected. The acceleration applied in the direction can be recognized. A case where acceleration is applied in the z direction will be described. When the movable comb electrode 342 is displaced in the positive z direction and is set to face the fixed comb electrode 345, the movable comb electrode 342 is moved in the positive z direction by acceleration. , The capacitance between the two electrodes decreases, while the displacement in the negative z direction increases the capacitance between the two electrodes. If the movable comb electrode 342 is displaced in the z-negative direction with respect to the fixed comb electrode 345 and set to face the fixed comb-wave electrode 345, when the movable comb-wave electrode 342 is displaced in the z-negative direction by acceleration, the capacitance between both electrodes decreases. , Z, the capacitance between both electrodes increases. As a result, the acceleration can be detected and measured.

(Configuration of Angular Velocity Sensor) The angular velocity sensor will be described with reference to FIG. Reference numeral 4 denotes a cross-shaped movable piece. A cross-shaped groove 40 is formed in the cross-shaped movable piece 4.
Are formed in the vertical direction. Reference numeral 42 denotes a movable piece fixing portion, which is formed so as to protrude slightly upward from the motion sensor common substrate 9 and is integrally formed therewith. Cross-shaped movable piece support 41
Is formed integrally with the movable piece fixing portion 42 so as to extend in a cross shape, and floats from the motion sensor common substrate 9 between the cross-shaped groove 40 at the tip of the cross-shaped movable piece 4 and the movable piece fixing portion 42. Connected in state. That is, the movable piece fixing portion 42
Holds the cross-shaped movable piece 4 in a neutral state around the cross-shaped movable piece support 41.

Reference numeral 43 denotes a movable drive electrode, which is integrally extended in an arc shape while floating from the motion sensor common substrate 9 from the side surface of the cross-shaped movable piece 4. Reference numeral 44 denotes a fixed-side drive electrode, which is integrally extended in an arc shape while floating from the motion sensor common substrate 9 from the side surface of the fixed-side drive electrode terminal 45. Movable drive electrode 4
As shown, the 3 and the fixed-side drive electrodes 44 are alternately interleaved and arranged to face each other, and the two electrodes eventually constitute a variable capacitance.

A monitor electrode 5 is formed above the distal end of the cross-shaped movable piece 4, and a detection electrode 6 is formed below it. Here, the monitor electrode 5 is set to have an interval between the monitor electrode 5 and the tip of the cross-shaped movable piece 4 in the motion sensor stationary state. The monitor electrode terminal 51 is connected to the motion sensor common substrate 9 via the insulating film 7. The detection electrode terminal 61 is formed directly on the motion sensor common substrate 9.

Here, the operation of the angular velocity sensor will be described. An AC drive voltage is applied between the fixed-side drive electrode terminal 45 and, for example, the movable piece fixed portion 42 forming the reference potential point. As for the method of applying the AC drive voltage,
From the viewpoint of simplifying the description, a case where an AC drive voltage is applied between any one of the fixed-side drive electrode terminals 45 and the movable piece fixing portion 42 will be described as an example.

(Operation of Angular Velocity Sensor) When an AC drive voltage is applied between the fixed drive electrode terminal 45 and the movable piece fixed portion 42, the AC drive voltage is applied between the movable drive electrode 43 and the fixed drive electrode 44. Is applied, a suction force and a repulsive force act between the two electrodes periodically and alternately. As a result, two adjacent pieces of the cross-shaped movable piece 4 are
The vibrations alternately approach and leave alternately around the center 2. This vibration can be brought into a resonance state by adjusting the frequency of the AC drive voltage. That is, both the piece of the cross-shaped movable piece 4 extending in the x direction and the piece of the cross-shaped movable piece 4 extending in the y direction perform bending vibration in the horizontal direction around the movable piece fixing portion 42.

As described above, in the state where the piece of the cross-shaped movable piece 4 is bending and vibrating in the horizontal direction about the movable piece fixing portion 42, assuming that the clockwise angular velocity is input in the x-axis direction, As a result of the Coriolis force being generated and acting on the piece of the cross-shaped movable piece 4 extending in the x direction, the distal ends of the left monitor electrode 5 and the left detection electrode 6 are displaced upward, while the right monitor electrode 5 and The tip on the right detection electrode 6 side is displaced downward. When the left end is displaced upward, the capacitance formed by the left monitor electrode 5 and the left detection electrode 6 becomes equal to the left monitor electrode 5 and the left end of the cross-shaped movable piece 4 at substantially the same potential as the left monitor electrode 6. It increases by approaching the electrode 5. On the other hand, the capacitance formed by the right monitor electrode 5 and the right detection electrode 6 is such that the tip of the cross-shaped movable piece 4 having substantially the same potential as the right detection electrode 6 approaches the right monitor electrode 5. It is reduced by It is detected that the capacitance formed by the left monitor electrode 5 and the left detection electrode 6 increases while the capacitance formed by the right monitor electrode 5 and the right detection electrode 6 decreases, whereby x It can be recognized that the clockwise angular velocity has been input in the axial direction.

Assuming that an angular velocity in the counterclockwise direction is input in the x-axis direction, the distal ends of the left monitor electrode 5 and the left detection electrode 6 are displaced downward, while the right monitor electrode 5 and the right detection electrode are displaced downward. The tip on the sixth side is displaced upward. It is detected that the capacitance formed by the left monitor electrode 5 and the left detection electrode 6 decreases while the capacitance formed by the right monitor electrode 5 and the right detection electrode 6 increases. It can be recognized that the angular velocity in the counterclockwise direction has been input in the axial direction.

Assuming that a clockwise angular velocity is input in the y-axis direction, a Coriolis force is generated and acts on one of the cross-shaped movable pieces 4 extending in the y-direction, so that the lower monitor electrode 5 and the lower The tip on the side detection electrode 6 side is displaced upward, while the tip on the upper monitor electrode 5 and the upper detection electrode 6 side is displaced downward. In this case, the lower monitor electrode 5
It is detected that the capacitance formed by the upper monitor electrode 5 and the upper detection electrode 6 decreases while the capacitance formed by the lower detection electrode 6 and the lower detection electrode 6 increases. It can be recognized that the clockwise angular velocity has been input.

Assuming that a counterclockwise angular velocity is input in the y-axis direction, the distal ends of the lower monitor electrode 5 and the lower detection electrode 6 are displaced downward, while the upper monitor electrode 5 and the upper monitor electrode 5 are displaced downward. The tip on the detection electrode 6 side is displaced upward. It is detected that while the capacitance formed by the lower monitor electrode 5 and the lower detection electrode 6 decreases, the capacitance formed by the upper monitor electrode 5 and the upper detection electrode 6 increases. Thus, it can be recognized that the angular velocity in the counterclockwise direction has been input in the y-axis direction.

[0032]

As described above, according to the present invention, the mass sensor of the acceleration sensor is formed on the semiconductor substrate in the form of a quadrangular frame surrounding the angular velocity sensor. As the mass can be increased, the acceleration detection accuracy can be improved accordingly.

Then, the quadrangular frame-shaped mass is held in a state of floating above the motion sensor common substrate by a mass support extending in a rectangular wave shape, and the mass support is raised from the motion sensor common substrate. By supporting the mass part base, which is formed slightly projecting, and connecting this mass part support to each side of the quadrangular frame of the mass part, the mass part is properly supported and applied. It responds quickly to acceleration.

Further, the interval between each one of the one comb electrodes and the other comb electrodes adjacent to both sides thereof is made different, and one of the comb electrodes is placed at a distance z with respect to the other. The three-axis acceleration sensor can be easily configured by displacing in the direction and setting the facing.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment viewed from above.

FIG. 2 is an enlarged perspective view showing a part of FIG. 1;

FIG. 3 is a perspective view of the angular velocity sensor in FIG. 1;

FIG. 4 is a diagram illustrating a conventional example.

FIG. 5 illustrates a detection circuit.

FIG. 6 is a diagram illustrating a part of FIG. 4;

[Explanation of symbols]

 Reference Signs List 1 mass part 21 to 24 mass part support 211, 212 mass part base 213, 214 base coupling part 215 mass part coupling part 25 ground electrode 31, 33 x-direction acceleration detection part 32, 34 y-direction acceleration detection part 341 acceleration Detection unit square hole 342 Movable comb wave electrode 343 Acceleration detection unit base 344 Support pole 345 Fixed comb wave electrode 4 Cross-shaped movable piece 40 Cross-shaped groove 41 Movable piece support 42 Movable piece fixed part 43 Movable drive electrode 44 Fixed side Drive electrode 45 Fixed-side drive electrode terminal 5 Monitor electrode 51 Monitor electrode terminal 6 Detection electrode 61 Detection electrode terminal 7 Insulating film 9 Motion sensor common board ac Acceleration sensor zy Angular velocity sensor

Claims (12)

[Claims] 1. A motion sensor comprising an angular velocity sensor and an acceleration sensor formed on a semiconductor substrate, wherein a mass portion constituting the acceleration sensor is a quadrangular frame formed around the angular velocity sensor. Motion sensor. 2. The motion sensor according to claim 1, wherein the quadrangular frame-shaped mass portion is held in a state of being floated from the motion sensor common substrate by a mass portion support extending in a rectangular wave shape. A motion sensor, comprising: 3. The motion sensor according to claim 2, wherein the mass support is supported by a mass base formed to project slightly upward from the motion sensor common substrate. Motion sensor. 4. The motion sensor according to claim 2, wherein the mass support is coupled to each side of the quadrangular frame of the mass. Motion sensor. 5. The motion sensor according to claim 1, wherein the acceleration detecting section is formed in an opening formed in a quadrangular frame of the mass section. Sensor. 6. The motion sensor according to claim 5, wherein the acceleration detector is a variable capacitance type acceleration detector. 7. The motion sensor according to claim 6, wherein an electrode surface forming a capacitance of the acceleration detector is set in parallel with the z direction. 8. The motion sensor according to claim 7, wherein the electrodes forming the capacitance include a plurality of movable comb electrodes extending from the mass part and acceleration detection formed to protrude from the motion sensor common substrate. A motion sensor comprising a plurality of movable comb electrodes extending from a base. 9. The motion sensor according to claim 8, wherein an acceleration detection unit sets the electrode surface parallel to the x direction and the z direction and an acceleration detection unit sets the electrode surface parallel to the y direction and the z direction. And a motion sensor. 10. The motion sensor according to claim 9, wherein the electrode surface is set in parallel with the x direction and the z direction, and a pair of acceleration detectors, and the electrode surface is set in parallel with the y direction and the z direction. A motion sensor comprising a pair of acceleration detectors. 11. The motion sensor according to claim 8, wherein a distance between each one of the one comb electrodes and another comb electrode adjacent to both surfaces thereof. And a comb sensor, wherein one of the comb electrodes is displaced in the z-direction with respect to the other, and is set to face the other. 12. The motion sensor according to claim 1, wherein the angular velocity sensor is a variable capacitance type angular velocity sensor.