Integration azimuth sensor

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a composite sensor in which a magnetic sensor and an acceleration sensor are mounted together, and in particular, an integrated sensor that is small enough to be incorporated in a portable device and can detect the attitude and orientation of the portable device, that is, an angle with respect to gravity and geomagnetism. It relates to a geomagnetic sensor.

【0002】

[Conventional technology]

Conventionally, as a posture detecting device for detecting a posture, the one described in Japanese Patent Application Laid-Open No. 10-185608 is known. This attitude detection device is composed of a magnetic sensor capable of detecting two-axis magnetic flux, a tilt sensor using a two-axis acceleration sensor, and an arithmetic circuit. The magnetic sensor, the tilt sensor, and the arithmetic circuit are formed on independent substrates, and each of these independent substrates is arranged on a separate substrate. The above magnetic sensor can detect geomagnetic components in the direction parallel (orthogonal 2) to the sensor surface.

【0003】

However, except for some areas near the equator, the direction of the geomagnetic vector is not horizontal with respect to the ground surface and there is a depression angle, so if the device is used in an inclined state, it will not be possible to detect the correct direction. It is possible. To eliminate this inconvenience, the tilt sensor detects the tilt of the device and corrects the output signal of the magnetic sensor, so that accurate geomagnetic orientation can be detected. On the other hand, as a small acceleration sensor having a function of directional measurement, the one described in JP-A-11-160349 is known. In this method, a Hall element for detecting a magnetic field perpendicular to the substrate surface is provided on the same substrate as the substrate constituting the acceleration sensor.

【0004】

As shown in FIG. 11, this acceleration sensor is provided with a silicon chip 15 having a beam structure in which a weight portion 14 is movably supported by a support portion 12 and a beam portion 13 on a glass pedestal 11. .. A movable electrode 16 is provided on the lower surface of the weight portion 14, and a fixed electrode 17 is provided on the upper surface of the pedestal 11. Further, a Hall element 18 is provided on the upper surface of the weight portion 14. The attitude detection device described in JP-A No. 10-185608 uses a fluxgate sensor as a magnetic sensor. Further, in the one described in JP-A-11-160349, a Hall element made of indium antimonide, gallium arsenide, or the like is used as the magnetic sensor.

【0005】

[Problems to be Solved by the Invention]

However, in the posture detection device described in Japanese Patent Application Laid-Open No. 10-185608, the magnetic sensor and the tilt angle sensor are formed on independent substrates, and the independent substrates are assembled. Therefore, when the posture detection device is mounted on a small device such as a mobile device, there is an inconvenience that it is too large. Further, in the one described in JP-A-11-160349, it is necessary to process the silicon chip 15, the pedestal 11, and the Hall element 18 from different substrates. Further, the silicon chip 15 has a disadvantage that both sides of the substrate need to be processed, which complicates the manufacturing process.

【0006】

By the way, the fluxgate sensor described in Japanese Patent Application Laid-Open No. 10-185608 is a (1-axis or) 2-axis magnetic sensor that detects magnetic components in a direction parallel to the sensor surface, and magnetism in a direction perpendicular to the sensor surface. The component cannot be detected. In the above publication, there are roughly two types of corrections as a method of obtaining the geomagnetic direction, that is, the horizontal component of the geomagnetism by performing a correction calculation based on the two-axis geomagnetic components of the fluxgate sensor using the output of the tilt sensor. The calculation method is described.

【0007】

In the first half, the correction calculation is performed assuming that the vertical component of the geomagnetism is 0. However, except for a very limited area near the equator, there is a vertical component in the geomagnetism, and it is known that the depression angle of the geomagnetism usually ranges from 35 degrees to 60 degrees in Japan. Therefore, if the correction method of the first half assuming that the vertical component of the geomagnetism is 0 is applied, only the direction of the horizontal component of the geomagnetism that should be originally obtained, that is, the result different from the geomagnetic direction can be obtained.

【0008】

On the other hand, in the latter half, the correction calculation is performed by regarding the vertical component of the geomagnetism as a constant value. Since the vertical component of the geomagnetism varies from place to place, this method requires a complicated operation of first standing the attitude detector vertically and measuring the vertical component of the geomagnetism each time the measurement location changes. There is. Further, this method has a problem that a large measurement error occurs in the measurement result when the attitude detection device is greatly tilted and the surface of the fluxgate sensor is close to vertical.

【0009】

Since the geomagnetic direction is the direction of the geomagnetic vector in the horizontal direction, it goes without saying that a magnetic sensor having at least two axes is required even if the conditions to be used, for example, the inclination are limited to horizontal. In JP-A-11-160349, a Hall element using indium antimonide, gallium arsenide, or the like is provided on a weight portion constituting the acceleration sensor. In general, the Hall element can detect only the magnetic flux density in the direction perpendicular to the sensitive surface, that is, one axis, so that it is impossible to know the exact orientation in such a configuration.

【0010】

Further, the above-mentioned publication does not describe at all a method of detecting the magnetic flux density of two or more axes using a Hall element, and even if the output of the tilt sensor is used, the direction of the horizontal component of the geomagnetism is corrected and calculated. I can't. Therefore, in view of the above points, an object of the present invention is to provide a compact integrated directional sensor capable of directional detection and posture detection and mounted on a mobile device.

【0011】

[Means for solving problems]

In order to solve the above problems and achieve the object of the present invention, the inventions according to claims 1 to 10 are configured as follows. That is, the invention according to claim 1 comprises a magnetic sensor having at least three axes for detecting geomagnetism, an acceleration sensor having two or more axes for detecting gravitational acceleration, an output signal from the magnetic sensor, and an output from the acceleration sensor. A signal processing unit for processing a signal is provided, the magnetic sensor, the acceleration sensor, and the signal processing unit are arranged on the same silicon substrate, and the acceleration sensor is a comb tooth fixed to the silicon substrate. It is characterized in that it is provided with a fixed electrode having a shape, a weight portion having a comb-shaped movable electrode facing the fixed electrode, and a beam that movably supports the weight portion on the silicon substrate. is there.

【0012】

The invention according to claim 2 is the integrated orientation sensor according to claim 1, wherein the magnetic sensor is arranged on the silicon substrate, and a magnetic convergence plate that converges magnetic flux in a direction along the surface of the silicon substrate. And at least three Hall elements on the surface side of the silicon substrate, which are arranged in the vicinity of a predetermined end portion of the magnetic focusing plate and detect magnetic flux spreading in the vicinity of each end portion thereof. It is characterized by that.

【0013】

The invention according to claim 3 is the integrated orientation sensor according to claim 1, wherein the magnetic sensor has a first magnetic convergence plate arranged at a predetermined position on the silicon substrate and the silicon substrate. A plurality of second magnetic convergence plates arranged at predetermined intervals in the outer peripheral direction around the first magnetic convergence plate, and the first magnetic convergence plate on the surface side of the silicon substrate. It is characterized in that, in each vicinity where the plate and each of the second magnetic focusing plates are adjacent to each other, a plurality of Hall elements for detecting magnetic flux spreading in the vicinity thereof are provided.

【0014】

The invention according to claim 4 is the integrated orientation sensor according to claim 1, wherein the magnetic sensor is on the silicon substrate and faces the first direction with a predetermined central portion thereof interposed therebetween. A first magnetic focusing plate that is arranged and converges the magnetic flux in the first direction thereof and a second direction on the silicon substrate that is orthogonal to the first direction with the central portion in between. A second magnetic flux converging plate that is arranged and converges the magnetic flux in the second direction, and end portions of the surface side of the silicon substrate on the central portion side of the first and second magnetic converging plates. It is characterized in that a Hall element for detecting magnetic flux spreading in the vicinity thereof is provided in the vicinity of the above.

【0015】

The invention according to claim 5 is the integrated orientation sensor according to claim 1, wherein the magnetic sensor has a cross-shaped magnetic focusing plate arranged at a predetermined position on the silicon substrate and a surface side of the silicon substrate. It is characterized in that, near each end of the magnetic focusing plate, a Hall element for detecting magnetic flux spreading in the vicinity thereof is provided. The invention according to claim 6 is the integrated directional sensor according to any one of claims 2 to 5, wherein the magnetic focusing plate is made of a thin plate made of a soft magnetic material. Is.

【0016】

The invention according to claim 7 is the integrated orientation sensor according to any one of claims 1 to 6, wherein the movable electrode, the weight portion, and the beam forming the acceleration sensor are made of the same polycrystalline silicon. It is characterized in that it is composed of a thin film. The invention according to claim 8 forms the magnetic sensor with a movable electrode, a weight portion, and a beam forming the acceleration sensor in the integrated orientation sensor according to any one of claims 1 to 6. The magnetic focusing plate is characterized in that it is made of the same soft magnetic thin film.

【0017】

The invention according to claim 9 comprises a magnetic sensor having at least three axes for detecting geomagnetism, an acceleration sensor having two or more axes for detecting gravitational acceleration, an output signal from the magnetic sensor, and an output signal from the acceleration sensor. A signal processing unit for processing is provided, and the magnetic sensor, the acceleration sensor, and the signal processing unit are arranged on the same silicon substrate, and the acceleration sensor provides a sensor arrangement space in a part of the silicon substrate. It is characterized in that a heating source is arranged in a central portion in the sensor arrangement space, and a pair of temperature sensors is arranged at positions facing each other across the heating source.

【0018】

The invention according to claim 10 is characterized in that, in the integrated directional sensor according to claim 9, the heating source and the temperature sensor are made of a thin film of polycrystalline silicon. According to the present invention having such a configuration, it is possible to detect the direction based on the geomagnetism and the gravitational acceleration, and it is possible to realize a compact integrated direction sensor that can be mounted on a mobile device or the like.

【0019】

Further, in the invention according to claim 3, since the number of magnetic focusing plates arranged can be increased, the effect of converging the magnetic flux by the magnetic focusing plates can be enhanced, and the sensitivity of the magnetic sensor can be increased. Further, in this case, since the number of Hall elements arranged can be increased, there is an advantage that the output after calculating the output voltage from each Hall element can be increased. Further, in the invention according to claim 4 or 5, the magnetic focusing plate can be formed into an elongated shape. Therefore, the demagnetic field coefficient of the magnetic converging plate becomes small, the effect of converging the magnetic flux in the horizontal direction with respect to the substrate on which the magnetic converging plate is arranged can be enhanced, and the sensitivity of the magnetic sensor can be increased.

【0020】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. (First Embodiment) FIG. 1 is a schematic perspective view showing the appearance of the first embodiment of the present invention. As shown in FIG. 1, the integrated azimuth sensor according to the first embodiment includes an acceleration sensor 3 having two or more axes for detecting gravity acceleration, a magnetic sensor 4 having at least three axes for detecting geomagnetism, and an acceleration sensor 3. The arithmetic processing unit 6 for calculating the azimuth angle by arithmetically processing the acceleration information from the sensor 4 and the magnetic information from the magnetic sensor 4 as described later is arranged on the same silicon substrate 7 which is an integrated sensor chip. It is designed to be miniaturized.

【0021】

In this example, the acceleration sensor 3 will be described as a 2-axis acceleration sensor, and the magnetic sensor 4 will be described as a 3-axis magnetic sensor. Next, the details of the configuration of the magnetic sensor 4 will be described with reference to FIG. FIG. 2 (A) is a plan view of the magnetic sensor 4, and FIG. 2 (B) is a sectional view taken along line AA of FIG. 2 (A). As shown in FIG. 2, the magnetic sensor 4 is formed on the surface of the silicon substrate 7. That is, the Hall elements 41 to 44 are formed at four predetermined positions on the surface of the silicon substrate 7. The Hall elements 41 to 44 are formed at the same time as the arithmetic processing unit 6 by the conventional method of forming a CMOS circuit.

【0022】

As shown in FIG. 2A, the Hall element 41 and the Hall element 42 are arranged so as to face each other in the X-axis direction on the surface of the silicon substrate 7. Further, the Hall element 43 and the Hall element 44 are arranged so as to face each other in the Y-axis direction on the surface of the silicon substrate 7. Therefore, the arrangement directions of the Hall elements 41 and 42 and the arrangement directions of the Hall elements 43 and 44 are orthogonal to each other. An insulating layer 51 is formed on the surfaces of the silicon substrate 7 and the Hall elements 41 to 44, and the magnetic focusing plate 45 is arranged on the surface of the insulating layer 51. The magnetic focusing plate 45 is composed of, for example, a disk-shaped thin plate (thin film) made of a soft magnetic material. The magnetic focusing plate 45 is arranged so that its center is positioned so that the Hall elements 41 and 42 and the Hall elements 43 and 44 are arranged orthogonally to each other. When the magnetic convergence plate 45 is arranged, the vicinity of the outer peripheral end portion of the magnetic convergence plate 45 faces the Hall elements 41 to 44.

【0023】

With such a configuration, the magnetic convergence plate 45 converges the magnetic flux parallel to the magnetic convergence plate 45. Next, the operation of the magnetic sensor 4 having such a configuration will be described with reference to FIG. First, the magnetic flux in the X-axis direction will be described. As shown in FIG. 2 (B), the magnetic flux Bx in the X-axis direction is converged in the X-axis direction by the magnetic convergence plate 45, but the magnetic flux spreads in the Z-axis direction at the end of the magnetic convergence plate 45, and the hole In the elements 41 and 42, the component of the magnetic flux in the Z-axis direction appears.

【0024】

At this time, the components of the magnetic fluxes of the Hall element 41 and the Hall element 42 in the Z-axis direction are opposite to each other. Therefore, if the difference between the output of the Hall element 41 and the output of the Hall element 42 is taken, the magnetic flux density in the X-axis direction can be obtained. Can be detected. At this time, even if a magnetic flux in the Z-axis direction is applied from the outside, the difference between the output of the Hall element 41 and the output of the Hall element 42 is taken, so that the difference is canceled. Regarding the magnetic flux in the Y-axis direction, even if it is converged by the magnetic focusing plate 45, it does not appear as a component in the Z-axis direction at the positions of the Hall elements 41 and 42.

【0025】

The magnetic flux density in the Y-axis direction can be detected by the Hall elements 43 and 44 by the same principle as the magnetic flux density in the X-axis direction. The magnetic flux density in the Z-axis direction can be detected by taking the sum of the outputs of the Hall elements 41 to 44. At this time, the magnetic flux in the X-axis direction applied from the outside is canceled by taking the sum of the output of the Hall element 41 and the output of the Hall element 42. Similarly, the magnetic flux in the Y-axis direction applied from the outside is canceled by taking the sum of the output of the Hall element 43 and the output of the Hall element 44.

【0026】

The above explanation can be expressed using a mathematical formula as follows. That is, assuming that the output voltages of the Hall elements 41, 42, 43, and 44 are Vh41, Vh42, Vh43, and Vh44, the outputs in the X-axis direction, Y-axis direction, and Z-axis direction after calculation are Dx, Dy, and Dz. It looks like this: Dx = Vh41-Vh42 Dy = Vh43-Vh44 Dz = Vh41 + Vh42 + Vh43 + Vh44 As described above, the magnetic sensor 4 can detect the magnetic flux vector in the three-dimensional space.

【0027】

Further, the magnetic sensor 4 is composed of a plurality of Hall elements 41 to 44 simultaneously formed on the same silicon substrate. Therefore, the Hall elements 41 to 44 have small variations in characteristics, and the temperature characteristics of the sensitivity also change. Therefore, the relative values of the three components of the geomagnetic vector are constant even when the temperature changes, and the direction of the geomagnetism can be detected with high accuracy. Next, the detailed configuration of the acceleration sensor 3 will be described with reference to FIG.

【0028】

FIG. 3 (A) is a plan view of the acceleration sensor 3, FIG. 3 (B) is a cross-sectional view of the EE line of the same figure (A), and FIG. 3 (C) is a cross-sectional view of the FF line of the same figure (A). .. As shown in FIG. 3, the acceleration sensor 3 has weight portions 8 arranged at predetermined intervals on the silicon substrate 7, and the weight portions 8 are formed on the silicon substrate by four beams 9a, 9b, 9c, and 9d. 7 It is movably supported on the top. As shown in FIG. 3, the weight portion 8 is made of a thin plate having a substantially square shape, and comb-shaped movable electrodes 21, 22, 23, and 24 are provided on each side thereof. The four corners of the weight portion 8 are connected to each end of the beams 9a, 9b, 9c, and 9d, respectively. The other ends of the beams 9a, 9b, 9c, and 9d are fixed to the beam support portions 25a, 25b, 25c, and 25d integrated with the silicon substrate 7.

【0029】

Comb-shaped fixed electrodes 31a and 31b are arranged as shown on the silicon substrate 7 at positions facing the fixed electrodes 21 of the weight portion 8 in order to form a capacitor. Each end of each of the fixed electrodes 31a and 31b is connected to the fixed electrode support portion 35, and the fixed electrode support portion 35 is fixed to the silicon substrate 7. Similarly, on the silicon substrate 7, comb-shaped fixed electrodes 32c, 32d, and fixed electrodes 33a are used to form capacitors at positions facing the fixed electrodes 22, 23, and 24 of the weight portion 8. , 33b, and fixed electrodes 34c, 34d, respectively.

【0030】

One ends of the fixed electrodes 32c and 32d, the fixed electrodes 33a and 33b, and the fixed electrodes 34c and 34d are connected to the fixed electrode supports 36, 37 and 38, and the fixed electrode supports 36, 37 and 38 are connected to the silicon substrate 7. It is fixed. The accelerometer 3 configured in this way has its constituent weights 8, comb-shaped movable electrodes 21 to 24, beams 9a to 9d, and comb-shaped fixed electrodes 31a, 31b, and so on. , Formed from a thin film of polycrystalline silicon. Further, each of these components may be formed of the soft magnetic thin film as well as the soft magnetic thin film forming the magnetic focusing plate 45 of the magnetic sensor 4.

【0031】

Next, the operation of the acceleration sensor 3 having such a configuration will be described. When an acceleration is applied to the acceleration sensor 3, an inertial force acts on the weight portion 8 in a direction opposite to the direction of the acceleration, and the weight portion 8 and the comb-shaped movable electrodes 21 to 24 move. At this time, the distance between the movable electrodes 21 to 24 and the corresponding fixed electrodes 31a, 31b, ... Changes, so by measuring the capacitance between these electrodes, the acceleration can be measured as follows. Can be sought.

【0032】

First, a case where acceleration is applied in the X-axis direction will be described. Here, in FIG. 3, the capacitance composed of the fixed electrode 31a and the movable electrode 21, and the fixed electrode 33a and the movable electrode 23 is Ca. Further, the capacitance composed of the fixed electrode 31b and the movable electrode 21 and the fixed electrode 33b and the movable electrode 23 is defined as Cb. When a positive acceleration is applied in the X-axis direction, the weight portion 8 moves in the negative direction of the X-axis due to inertial force when viewed from the silicon substrate 7. Therefore, the capacitance Ca increases and the capacitance Cb decreases. On the other hand, when accelerations in the Y-axis direction and the Z-axis direction are applied, the changes in capacitance Ca and capacitance Cb are the same.

【0033】

Therefore, the capacitance Ca and the capacitance Cb are converted into voltages Va and Vb by the capacitance-voltage conversion circuit (not shown), respectively, and the difference circuit (not shown) is the difference between the conversion voltages Va and Vb (Va). By taking -Vb), the acceleration in the X-axis direction can be obtained as the voltage signal Ka. Next, a case where acceleration is applied in the Y-axis direction will be described. Here, in FIG. 3, the capacitance composed of the fixed electrode 32c and the movable electrode 22, and the fixed electrode 34c and the movable electrode 24 is defined as Cc. Further, the capacitance composed of the fixed electrode 32d and the movable electrode 22 and the fixed electrode 34d and the movable electrode 24 is defined as Cd.

【0034】

When a positive acceleration is applied in the Y-axis direction, the weight portion 8 moves in the negative direction of the Y-axis due to inertial force when viewed from the silicon substrate 7. Therefore, the capacitance Cc increases and the capacitance Cd decreases. On the other hand, when accelerations in the Y-axis direction and the Z-axis direction are applied, the changes in capacitance Cc and capacitance Cd are the same. Therefore, the capacitance Cc and the capacitance Cd are converted into voltages Vc and Vd by the capacitance-voltage conversion circuit (not shown), respectively, and the difference circuit (not shown) is the difference between the converted voltages Vc and Vd (Vc). By taking -Vd), the acceleration in the Y-axis direction can be obtained as the voltage signal Kb.

【0035】

As described above, since the acceleration sensor 3 can detect the acceleration of two axes parallel to the substrate surface of the silicon substrate 7, the inclination of the gravitational acceleration with respect to the substrate surface with respect to the ground surface is measured by the acceleration sensor 3. Can be sought. Next, the configuration of the arithmetic processing unit 6 that arithmetically processes the output signal of the acceleration sensor 3 and the output signal of the magnetic sensor 4 configured as described above will be described with reference to the block diagram of FIG.

【0036】

As shown in FIG. 4, the arithmetic processing unit 6 includes an A / D conversion unit 115, a temperature sensor 113, a correction calculation unit 116, a correction value storage unit 117, and an azimuth angle calculation unit 118. Is integrated on the silicon substrate 7. Since the output signals Ka and Kb of the 2-axis acceleration sensor 3 and the output signals Dx, Dy and Dz of the 3-axis magnetic sensor 4 are analog signals, the A / D converter 115 digitalizes these analog signals. It is converted into a signal (digital value).

【0037】

The temperature sensor 113 is a sensor for correcting the temperature characteristics of the acceleration sensor described later, and its detected temperature (output signal) is converted into a digital signal by the A / D converter 115 and sent to the correction calculation unit 116. .. The correction value storage unit 117 includes offset values Lx, Ly, Lz of the X-axis, Y-axis, and Z-axis output signals Dx, Dy, and Dz of the magnetic sensor 4, and temperature coefficients T1x, T1y, and T1z of the offset values. It is a memory that stores the sensitivity ratios Gx, Gy, and Gz.

【0038】

Further, the correction value storage unit 117 includes offset values Mx and My of the X-axis and Y-axis output signals Ka and Kb of the 2-axis accelerometer 3, temperature coefficients Tmx and Tmy of the offset values, and a sensitivity ratio Hx. , Hy and the temperature coefficients Thx and Thy of each sensitivity ratio are stored. In this way, the correction value storage unit 117 stores the correction data in the offset and temperature dependence of the output signals Dx, Dy, Dz of the magnetic sensor 4 and the output signals Ka, Kb of the acceleration sensor 3. This is to correct (compensate) these.

【0039】

The correction calculation unit 116 uses the offset values Lx, Ly, Lz, the sensitivity ratios Gx, Gy, Gz, and the temperature coefficients T1x, T1y, and T1z stored in the correction value storage unit 117 to display the output signal of the magnetic sensor 4. Dx, Dy, and Dz are corrected, and only the values α, β, and γ proportional to each axis component of the geomagnetism are obtained, and these are output to the azimuth calculation unit 118. Further, the correction calculation unit 116 uses the offset values Mx, My, temperature coefficient Tmx, Tmy, sensitivity ratio Hx, Hy, and temperature coefficient Thx, Thy stored in the correction value storage unit 117, so that the acceleration sensor 3 The output signals Ka and Kb are corrected, the two-axis slopes φ and η with respect to gravity are obtained, and these are output to the azimuth angle calculation unit 118.

【0040】

Here, in the 3-axis magnetic sensor 4, since the temperature coefficients of the sensitivities (sensitivity ratios) of the Hall elements 41 to 44, which are the constituent elements, are all equal, if only the direction of the geomagnetism is to be obtained, the sensitivities are as described above. There is no need to correct the temperature coefficient of. On the other hand, since the acceleration sensor 3 has two axes, an absolute value is required as the output signal in order to obtain the inclination with respect to gravity, and the temperature coefficient of sensitivity needs to be corrected as described above. The azimuth calculation unit 118 uses the three-axis data α, β, and γ of the geomagnetism corrected by the correction calculation unit 116 and the two-axis slopes φ and η with respect to gravity, so that the azimuth angle θ will be described later. Is calculated.

【0041】

Next, an example of an algorithm in which the azimuth angle calculation unit 118 calculates the azimuth angle θ in the arithmetic processing unit 6 having such a configuration will be described below. Here, in the azimuth calculation unit 118, the sensitivity, offset, and temperature coefficient are corrected, and the three-axis geomagnetic data α, β, γ, and the two-axis slopes φ and η with respect to gravity are corrected in the correction calculation unit 116. It shall be input from. FIG. 5 is a diagram showing the relationship between the geomagnetic vector and the rotation axis when calculating the azimuth angle θ.

【0042】

In FIG. 5, the TMx axis is set corresponding to the geomagnetic vector (x, y, z), and the two axes orthogonal to the TMx axis are the TMy axis and the TMz axis. Further, when this first embodiment is mounted on the mobile terminal 110 and used, the orientation of the mobile terminal 110 with respect to the geomagnetic vector (x, y, z) is θ, and the depression angle is δ. Further, it is assumed that the mobile terminal 110 is tilted from the horizontal plane by an angle φ in the longitudinal direction and an angle η in the lateral direction.

【0043】

Then, in order to correct the depression angle δ, it is rotated by -δ around the TMy axis, and the axes after this rotation are HX, HY, and HZ. Next, it is rotated around the HZ axis by an angle θ, and the axes after this rotation are M1x, M1y, and M1z. Next, rotate around the M1y axis by -φ, set the rotated axes as M2x, M2y, and M2z, and further rotate around the M2x axis by -η.

【0044】

Due to these rotations, the following equation (1) holds between the geomagnetic vector (x, y, z) and the output (α, β, γ) from the magnetic sensor 4.

【0045】

[Number 1]

<img file="JP2003194574A_D0001.tif" />【0046】

Then, when the output (α, β, γ) from the magnetic sensor is obtained from the relationship of the magnetic vector (x, y, z) = (1, 0, 0), the following equation (2) is obtained.

【0047】

[Number 2]

<img file="JP2003194574A_D0002.tif" />【0048】

Next, by transforming the equation of α in equation (2), the following equation (3) is obtained.

【0049】

[Number 3]

<img file="JP2003194574A_D0003.tif" />【0050】

Next, by substituting Eqs. (3) into the β and γ equations of (2), the following equations (4) and (5) are obtained.

【0051】

[Number 4]

<img file="JP2003194574A_D0004.tif" />【0052】

Next, when cos (δ) is obtained from equations (4) and (5), the following equation (6) is obtained.

【0053】

[Number 5]

<img file="JP2003194574A_D0005.tif" />【0054】

Next, by modifying Eq. (6) to obtain the azimuth angle θ, Eq. (7) shown below can be obtained.

【0055】

[Number 6]

<img file="JP2003194574A_D0006.tif" />【0056】

In this way, by using the three-axis geomagnetic data α, β, γ, and the two-axis tilt data φ, η with respect to gravity, the azimuth angle θ can be calculated without using the depression angle δ. As described above, in the first embodiment, the acceleration sensor 3, the magnetic sensor 4, and the arithmetic processing unit 6 are arranged on the same silicon substrate 7, so that the overall size can be reduced. it can.

【0057】

Further, in the first embodiment, the magnetic sensor 4 is composed of a plurality of Hall elements 41 to 44 simultaneously formed on the same silicon substrate. Therefore, the Hall elements 41 to 44 have small variations in characteristics, and the temperature characteristics of the sensitivity also change. Therefore, the relative values of the three components of the geomagnetic vector are constant even when the temperature changes, and the direction of the geomagnetism can be detected with high accuracy. In the first embodiment, the output signal of the acceleration sensor 3 and the output signal of the magnetic sensor 4 are electrically connected on the silicon substrate 7 by appropriate means so as to be supplied to the arithmetic processing unit 6. Moreover, the arithmetic processing result of the arithmetic processing unit 6 can be output to the outside. (Second Embodiment) In this second embodiment, the basic configuration thereof is the same as that of the first embodiment, and the magnetic sensor 4 (see FIG. 2) is replaced with the magnetic sensor 4A as shown in FIG. It is a thing. Therefore, in the following, only the configuration of the magnetic sensor 4A will be described.

【0058】

6A and 6B are views showing the configuration of the magnetic sensor 4A, FIG. 6A is a plan view of the magnetic sensor 4A, and FIG. 6B is a cross-sectional view of the BB line of FIG. 6A. .. As shown in FIG. 6, the magnetic sensor 4A has a magnetic focusing plate 65 made of, for example, a circular thin plate, arranged at a predetermined position on the silicon substrate 7. Further, around the magnetic converging plate 65 at a predetermined distance, four magnetic converging plates 66 to 69 made of, for example, circular thin plates are arranged at a predetermined distance in the outer peripheral direction of the magnetic converging plate 65. I have to. The magnetic focusing plates 65 to 69 are made of, for example, a soft magnetic material.

【0059】

Further, in detail, two magnetic convergence plates 66 and 67 are arranged on the left and right sides of the magnetic convergence plate 65 at predetermined intervals, and two magnetic convergence plates are arranged at predetermined intervals before and after the magnetic convergence plate 65. 68 and 69 are placed. Therefore, the magnetic convergence plates 67, 65, 66 are arranged in the X-axis direction at predetermined intervals, and the magnetic convergence plates 68, 65, 69 are arranged in the Y-axis direction at predetermined intervals. Of the surface region of the silicon substrate 7, the magnetic convergence plate 65 and the magnetic convergence plates 66, 67, 68, 69 are in the vicinity of the adjacent region, and the magnetic convergence plate 65 and the magnetic convergence plates 66, 67, 68, 69 are located. Hall elements 61a, 61b, 62a, 62b, 63a, 63b, 64a, and 64b are arranged on the lower side of the end portions facing each other.

【0060】

That is, as shown in FIG. 6, the Hall element 61a is located on the surface of the silicon substrate 7 near the lower side of the positions of the ends where the magnetic focusing plate 65 and the magnetic focusing plate 66 face each other. 61b is placed. Further, Hall elements 62a and 62b are arranged on the surface of the silicon substrate 7 near the lower side of each end portion where the magnetic convergence plate 65 and the magnetic convergence plate 67 face each other. Therefore, the arrangement direction of the Hall elements 61a, 61b, 62a, and 62b is the X-axis direction.

【0061】

Further, Hall elements 63a and 63b are arranged on the surface of the silicon substrate 7 near the lower side of each end portion where the magnetic convergence plate 65 and the magnetic convergence plate 68 face each other. Further, Hall elements 64a and 64b are arranged on the surface of the silicon substrate 7 near the lower side of each end portion where the magnetic convergence plate 65 and the magnetic convergence plate 69 face each other. Therefore, the arrangement direction of the Hall elements 63a, 63b, 64a, and 64b is the Y-axis direction.

【0062】

Next, the operation of the magnetic sensor 4A having such a configuration will be described with reference to FIG. Now, when a magnetic field is applied from the outside in the X-axis direction, the magnetic flux is converged by the magnetic focusing plates 67, 65, 66. The converged magnetic flux has a gap between the magnetic convergence plate 65 and the magnetic convergence plate 67, and between the magnetic convergence plate 65 and the magnetic convergence plate 66. Therefore, the converged magnetic flux spreads in the Z-axis direction in the region of the gap as shown in FIG. 6 (B).

【0063】

At this time, the components of the magnetic flux in the Z-axis direction are the same for the Hall elements 61a and 62b, whereas the Hall elements 61b and 62a are the same in the opposite directions to the Hall elements 61a and 62b. Therefore, the sum of the output voltage of the Hall element 61a and the output voltage of the Hall element 62b and the sum of the output voltage of the Hall element 61b and the output voltage of the Hall element 62a are obtained, and the difference between the two is taken to obtain the X-axis. The magnetic flux density in the direction can be obtained.

【0064】

With respect to the external magnetic field in the Y-axis direction, the components in the Z-axis direction do not appear at the positions of the Hall elements 61a, 61b, 62a, and 62b. With respect to the external magnetic field in the Z-axis direction, the output voltages of the Hall elements 61a, 61b, 62a, and 62b are all the same, and do not appear in the output in the X-axis direction after calculation. The detection of the magnetic flux density in the Y-axis direction can be performed by calculating the output voltages of the Hall elements 63a, 63b, 64a, and 64b in the same manner as in the case of the X-axis direction.

【0065】

The magnetic flux density in the Z-axis direction is detected by summing the output voltages of all Hall elements 61a, 61b, 62a, 62b, 63a, 63b, 64a, and 64b. At this time, since the output voltages of the pair of Hall elements such as Hall elements 61a and 61b are opposite to the external magnetic fields in the X-axis direction and the Y-axis direction, the output is zero by taking the sum of these. It becomes. The above explanation can be expressed using a mathematical formula as follows.

【0066】

That is, assuming that the output voltages of the Hall elements 61a, 61b, 62a, 62b, 63a, 63b, 64a, 64b are Vh61a, Vh61b, Vh62a, Vh62b, Vh63a, Vh63b, Vh64a, Vh64b, the X-axis direction and Y-axis after calculation The directional and Z-axis outputs are Dx, Dy, and Dz as follows. Dx = Vh61a-Vh61b-Vh62a + Vh62b Dy = Vh63a-Vh63b-Vh64a + Vh64b Dz = Vh61a + Vh61b + Vh62a + Vh62b + Vh63a + Vh63b + Vh64a + Vh64b As described above, the magnetic sensor 4A of the second embodiment can increase the number of magnetic focusing plates arranged as shown in FIG. 6 as compared with the magnetic sensor 4 of the first embodiment. Therefore, the effect of converging the magnetic flux by the magnetic converging plate can be enhanced, and the sensitivity of the magnetic sensor can be increased.

【0067】

Further, in this case, since the number of Hall elements constituting the magnetic sensor 4A can be increased, there is an advantage that the output voltage after the calculation of the output voltage from each Hall element can be increased. Although the magnetic sensor 4A is integrally provided on the silicon substrate 7 together with the acceleration sensor 3 and the like, it can be configured independently and used for general purposes. This also applies to the magnetic sensor described later. (Third Embodiment) In this third embodiment, the basic configuration thereof is the same as that of the first embodiment, and the magnetic sensor 4 (see FIG. 2) is replaced with the magnetic sensor 4B as shown in FIG. It is a thing. Therefore, in the following, only the configuration of the magnetic sensor 4B will be described.

【0068】

7A and 7B are views showing the configuration of the magnetic sensor 4B, FIG. 7A is a plan view of the magnetic sensor 4B, and FIG. 7B is a sectional view taken along line CC of FIG. 7B. .. As shown in FIG. 7, the magnetic sensor 4B is provided with a central portion 80 having a predetermined size at a predetermined position on the silicon substrate 7, and the central portion 80 is sandwiched between the central portions 80 on the left and right sides of the central portion 80. The magnetic converging plate 77 is arranged, and the magnetic converging plate 78 and the magnetic converging plate 79 are arranged so as to sandwich the central portion 80 in front of and behind the central portion 80.

【0069】

That is, the magnetic flux converging plate 76 and the magnetic flux converging plate 77 are arranged so as to face each other in the X-axis direction with the central portion 80 interposed therebetween. Further, the magnetic flux converging plate 78 and the magnetic flux converging plate 79 are arranged so as to face each other in the Y-axis direction with the central portion 80 interposed therebetween. The magnetic focusing plates 76 to 79 are respectively arranged on the silicon substrate 7 with the insulating layer 51 interposed therebetween. As shown in the figure, the magnetic focusing plates 76 to 79 each have an elongated shape. As shown in FIG. 7, in the surface region of the silicon substrate 7, Hall elements 71 to 74 are located in the vicinity of each end of the magnetic focusing plates 76 to 79 on the central portion 80 side, and on each lower side thereof. Each is arranged.

【0070】

Next, the operation of the magnetic sensor 4B having such a configuration will be described with reference to FIG. 7. Now, when a magnetic field is applied from the outside in the X-axis direction, the magnetic flux is converged by the magnetic focusing plates 76 and 77. This converged magnetic flux has a gap between the magnetic focusing plate 76 and the magnetic focusing plate 77. Therefore, the converged magnetic flux spreads in the Z-axis direction in the region of the gap as shown in FIG. 7 (B).

【0071】

At this time, the components of the magnetic flux in the Z-axis direction are opposite in the Hall element 71 and the Hall element 72. Therefore, the magnetic flux density in the X-axis direction can be obtained by taking the difference between the output voltage of the Hall element 71 and the output voltage of the Hall element 72. At this time, the Z-axis component does not appear at the positions of the Hall elements 71 and 72 with respect to the external magnetic field in the Y-axis direction. Relative to the Z-axis direction of the external magnetic field, Ho output voltage of Lumpur elements 71, 72, 73 and 74 are all the same, it does not appear in the output of the X-axis direction after the operation.

【0072】

The detection of the magnetic flux density in the Y-axis direction can be performed by calculating the output voltages of the Hall elements 73 and 74 in the same manner as in the case of the X-axis direction. The magnetic flux density in the Z-axis direction is detected by summing the output voltages of all Hall elements 71 to 74. At this time, the outputs of the Hall element 71 and the Hall element 72, and the Hall element 73 and the Hall element 74 are opposite to the external magnetic fields in the X-axis direction and the Y-axis direction. The output will be zero.

【0073】

The above explanation can be expressed using a mathematical formula as follows. That is, assuming that the output voltages of the Hall elements 71, 72, 73, and 74 are Vh71, Vh72, Vh73, and Vh74, the outputs in the X-axis direction, Y-axis direction, and Z-axis direction after calculation are Dx, Dy, and Dz. It looks like this: Dx = Vh71-Vh72 Dy = Vh73-Vh74 Dz = Vh71 + Vh72 + Vh73 + Vh74 As described above, in the magnetic sensor 4B of the third embodiment, since the magnetic focusing plates 76 to 79 have an elongated shape, the demagnetic field coefficient of the magnetic focusing plate becomes small, and the magnetic fluxing plate is placed on the substrate. Therefore, the effect of converging the magnetic flux in the horizontal direction can be enhanced, and the sensitivity of the magnetic sensor can be increased. (Fourth Embodiment) In this fourth embodiment, the basic configuration thereof is the same as that of the first embodiment, and the magnetic sensor 4 (see FIG. 2) is replaced with the magnetic sensor 4C as shown in FIG. It is a thing. Therefore, in the following, only the configuration of the magnetic sensor 4C will be described.

【0074】

FIG. 8 is a diagram showing the configuration of the magnetic sensor 4C, FIG. 8 (A) is a plan view of the magnetic sensor 4C, and FIG. 8 (B) is a cross-sectional view of the DD line of FIG. 8 (A). .. As shown in FIG. 8, this magnetic sensor 4C has a cross-shaped magnetic focusing plate 85 made of a soft magnetic material arranged at a predetermined position on a silicon substrate 7. The magnetic focusing plate 85 has an elongated thin plate shape as a whole, and the portion in the X-axis direction and the portion in the Y-axis direction are orthogonal to each other. The magnetic focusing plate 85 is arranged on the silicon substrate 7 with an insulating layer 51 interposed therebetween.

【0075】

As shown in FIG. 8, of the surface region of the silicon substrate 7, Hall elements are located near each end of each portion of the magnetic focusing plate 85 in the X-axis direction and the Y-axis direction, and on each lower side thereof. 81 to 84 are arranged respectively. Next, the operation of the magnetic sensor 4C having such a configuration will be described with reference to FIG. Now, when a magnetic field is applied from the outside in the X-axis direction, the magnetic flux is converged by the part of the magnetic convergence plate 85 in the X-axis direction. As shown in FIG. 8 (B), this converged magnetic flux spreads in the Z-axis direction at the end of the portion of the magnetic convergence plate 85 in the X-axis direction.

【0076】

At this time, the components of the magnetic flux in the Z-axis direction are opposite in the Hall element 81 and the Hall element 82. Therefore, the magnetic flux density in the X-axis direction can be obtained by taking the difference between the output voltage of the Hall element 81 and the output voltage of the Hall element 82. At this time, the Z-axis component does not appear at the positions of the Hall elements 81 and 82 with respect to the external magnetic field in the Y-axis direction. With respect to the external magnetic field in the Z-axis direction, the output voltages of the Hall elements 81, 82, 83, and 84 are all the same, and do not appear in the output in the X-axis direction after the calculation.

【0077】

The detection of the magnetic flux density in the Y-axis direction can be performed by calculating the output voltages of the Hall elements 83 and 84 in the same manner as in the case of the X-axis direction. The magnetic flux density in the Z-axis direction is detected by summing the output voltages of all Hall elements 81 to 84. At this time, the outputs of the Hall element 81 and the Hall element 82, and the Hall element 83 and the Hall element 84 are opposite to each other with respect to the external magnetic fields in the X-axis direction and the Y-axis direction. The output will be zero.

【0078】

The above explanation can be expressed using a mathematical formula as follows. That is, assuming that the output voltages of the Hall elements 81, 82, 83, and 84 are Vh81, Vh82, Vh83, and Vh84, the outputs in the X-axis direction, Y-axis direction, and Z-axis direction after calculation are Dx, Dy, and Dz. It looks like this: Dx = Vh81-Vh82 Dy = Vh83-Vh84 Dz = Vh81 + Vh82 + Vh83 + Vh84 As described above, in the magnetic sensor 4C of the fourth embodiment, since the magnetic converging plate 85 has an elongated shape, the demagnetic field coefficient of the magnetic converging plate becomes small, and it is horizontal to the substrate on which the magnetic converging plate is arranged. The effect of converging the magnetic flux in the direction can be enhanced, and the sensitivity of the magnetic sensor can be increased. (Fifth Embodiment) In this fifth embodiment, the basic configuration thereof is the same as that of the first embodiment, and the acceleration sensor 3 (see FIG. 3) is replaced with the acceleration sensor 3A as shown in FIG. It is a thing. Therefore, in the following, only the configuration of the acceleration sensor 3A will be described.

【0079】

FIG. 9 is a diagram showing the configuration of the acceleration sensor 3A, FIG. 9 (A) is a plan view of the acceleration sensor 3A with the top lid removed, and FIG. 9 (B) shows the top lid of the same figure (A). It is sectional drawing of the GG line in the attached state. As shown in FIG. 9, the acceleration sensor 3A forms a sealed sensor arrangement space 102 by a recess 90 formed at a predetermined position on the silicon substrate 7 and a concave upper lid 101 that seals the recess 90. Each component of the acceleration sensor 3A is arranged in the sensor arrangement space 102.

【0080】

That is, the heater 91, which is a heating source, is arranged in the central portion of the sensor arrangement space 102, and the temperature sensor 92 and the temperature sensor 93, and the temperature sensor 94 and the temperature sensor 95 sandwich the heater 91 around the heater 91. , Are arranged facing each other. More specifically, the heater forming portion 96 and the temperature sensor forming portion 97 formed of a quadrangular frame are arranged substantially concentrically around the heater forming portion 96 in the center of the upper portion in the recess 90. The heater forming portion 96 is connected to the temperature sensor forming portion 97 by four beams 98, and each corner of the temperature sensor forming portion 97 is connected to the support portion 100 formed of a quadrangular frame by four beams 99. The support portion 100 is fixed on the silicon substrate 7. On the upper side of the recess 90, an upper lid 101 is arranged so as to seal the recess 90, and the lower end portion of the upper lid 101 is fixed to the support portion 100.

【0081】

In this example, the heater forming part 96, the four beams 98, the temperature sensor forming part 97, the four beams 99, and the support part 100 are SiO.₂It is integrally formed by an insulator made of or SiN. A heater 91 is embedded in the heater forming portion 96. The heater 91 is made of, for example, a strip of polycrystalline silicon thin film. A current is passed through the heater 91 through an electric wiring (not shown), whereby the heater 91 generates heat due to the resistance component of the polycrystalline silicon.

【0082】

The temperature sensor forming portion 97 is composed of a front portion, a rear portion, a left portion, and a right portion in order to form a quadrangular frame, and temperature sensors 92 to 95 are arranged in each portion. As shown in the figure, the temperature sensors 92 to 95 are arranged at equidistant positions from the arrangement position of the heater 91. The temperature sensors 92 to 95 are made of, for example, a strip of polycrystalline silicon thin film. Since the resistance component of polycrystalline silicon has a temperature coefficient, the temperature sensors 92 to 95 measure the temperature by measuring the resistance value.

【0083】

Next, the operation of the acceleration sensor 3A having such a configuration will be described with reference to FIG. When an electric current is passed through the heater 91 to heat it, the temperature of the gas around the heater 91 rises. When no acceleration is applied to the acceleration sensor 3A, the temperature distribution around the heater 91 decreases substantially concentrically around the heater 91 from the center to the periphery. In addition, the distribution of gas density around it is the smallest at the center and increases toward the surroundings. Therefore, the temperatures are all equal at the positions of the four temperature sensors 92 to 95, and the resistance values of the polycrystalline silicon constituting the temperature sensors 92 to 95 are also all equal.

【0084】

Considering the case where acceleration is applied in the X-axis direction, the region where the gas density is low moves in the X-axis direction due to the acceleration. At this time, the temperature distribution changes as the density of the gas moves, that is, the high temperature region moves in the X-axis direction, and the temperature of the temperature sensor 92 becomes higher than the temperature of the temperature sensor 93. Therefore, there is a difference in the resistance values of the polycrystalline silicon of the temperature sensor 92 and the temperature sensor 93. At this time, the temperatures of the temperature sensor 94 and the temperature sensor 95 are equal, and the resistance values of the polycrystalline silicon are also equal.

【0085】

When the acceleration is applied in the Y-axis direction, it can be considered in the same manner as when the acceleration is applied in the X-axis direction. That is, in this case, there is a difference in the resistance values of the polycrystalline silicon of the temperature sensor 94 and the temperature sensor 95. On the other hand, the temperatures of the temperature sensor 92 and the temperature sensor 93 are equal, and the resistance values of the polycrystalline silicon are equal. When acceleration is applied in the Z-axis direction, the temperature distribution changes, but the temperatures are all the same at each position of the four temperature sensors 92 to 95, and the resistance values of the polycrystalline silicon are also the same.

【0086】

The above description will be described below using mathematical formulas. Now, it is assumed that the resistance values of the polycrystalline silicon constituting the temperature sensors 92 to 95 are R92, R93, R94, and R95, and when the temperatures are the same, the resistance values are all the same. Further, the temperature sensor 92 and the temperature sensor 93 are connected in series, a voltage Vb is applied to both ends thereof, and an output voltage V1 of the common connection portion is taken out. Further, the temperature sensor 94 and the temperature sensor 95 are connected in series, a voltage Vb is applied to both ends thereof, and an output voltage V2 of the common connection portion is taken out. This electrical equivalent circuit is shown in FIG.

【0087】

Under such conditions, when acceleration is not applied to the acceleration sensor 3A, the output voltages V1 and V2 are V1 = V2 = Vb / 2. When acceleration is applied in the X-axis direction, V1 = (Vb / 2) ± ΔVx, and this change ΔVx is a voltage that is almost proportional to the acceleration. At this time, V2 = Vb / 2. When acceleration is applied in the Y-axis direction, V2 = (Vb / 2) ± ΔVy, and this change ΔVy is a voltage that is almost proportional to the acceleration. At this time, V1 = Vb / 2.

【0088】

As described above, since the acceleration sensor 3A of the fifth embodiment can detect the acceleration in the X-axis direction and the Y-axis direction parallel to the substrate surface, the cosine of the gravitational acceleration with respect to the substrate surface is the acceleration sensor 3A. The inclination with respect to the ground surface can be obtained by measuring with. The acceleration sensor 3A is sealed by locally covering the component elements of the sensor with the upper lid 101. However, instead of the upper lid 101, the entire upper surface of the silicon substrate 7 may be covered in a sealed manner by a case (see FIG. 1).

【0089】

The integrated directional sensor according to the fifth embodiment is a combination of the acceleration sensor 3A shown in FIG. 9 and the magnetic sensor 4 shown in FIG. However, in the integrated directional sensor according to the fifth embodiment, the magnetic sensor 4 shown in FIG. 2 is replaced with one of the magnetic sensors 4A, 4B, and 4C shown in FIGS. 6 to 8. You may.

【0090】

[Effect of the invention]

As described above, according to the present invention, it is possible to detect the direction based on the geomagnetism and the gravitational acceleration, and it is possible to realize a small and low-cost integrated direction sensor that can be mounted on a mobile device or the like. Further, in the present invention, when the number of magnetic focusing plates arranged is increased, the effect of converging the magnetic flux by the magnetic focusing plates can be enhanced, and the sensitivity of the magnetic sensor can be increased. In this case, since the number of Hall elements constituting the magnetic sensor can be increased, there is an advantage that the output voltage after calculating the output voltage from each Hall element can be increased.

【0091】

Furthermore, in the present invention, when the magnetic converging plate has an elongated shape, the demagnetic field coefficient of the magnetic converging plate becomes small, and the effect of converging the magnetic flux in the horizontal direction with respect to the substrate on which the magnetic converging plate is arranged is enhanced. , The sensitivity of the magnetic sensor can be increased.

[Simple explanation of drawings]

[Figure 1]

It is a perspective view which shows the appearance structure of 1st Embodiment of the integrated directional sensor of this invention.

[Figure 2]

It is a figure which shows the structure of the magnetic sensor which concerns on 1st Embodiment, (A) is the plan view, (B) is the sectional view of the AA line of (A).

[Fig. 3]

It is a figure which shows the structure of the acceleration sensor which concerns on 1st Embodiment, (A) is the plan view, (B) is the sectional view of the EE line of (A), (C) is the sectional view of the FF line of (A). It is a figure.

[Fig. 4]

It is a block diagram which shows the structure of the arithmetic processing part in 1st Embodiment.

[Fig. 5]

It is a figure which shows the relationship between the geomagnetic vector and the rotation axis in 1st Embodiment.

[Fig. 6]

It is a figure which shows the structure of the magnetic sensor of 2nd Embodiment, (A) is the plan view, (B) is the sectional view of the BB line of (A).

[Fig. 7]

It is a figure which shows the structure of the magnetic sensor of 3rd Embodiment, (A) is the plan view, (B) is the sectional view of CC line of (A).

[Fig. 8]

It is a figure which shows the structure of the magnetic sensor of 4th Embodiment, (A) is the plan view, (B) is the sectional view of the DD line of (A).

[Fig. 9]

It is a figure which shows the structure of the acceleration sensor of 5th Embodiment, (A) is the plan view, (B) is the sectional view of the GG line of (A).

[Fig. 10]

It is a figure which shows the electrical equivalent circuit of the temperature sensor shown in FIG.

[Fig. 11]

It is sectional drawing which shows the structural example of the conventional sensor.

[Explanation of symbols]

3, 3A accelerometer 4, 4A ~ 4C magnetic sensor 6 Arithmetic processing unit 7 Silicon substrate 8 Weight 9a ~ 9d beam 21 ~ 24 Comb-shaped movable electrode 31a, 31b, 33a, 33b Comb-shaped fixed electrodes 32c, 32d, 34c, 34d Comb-shaped fixed electrodes 41 ~ 44 Hall element 45 Magnetic convergence plate 61a, 61b, 62a, 62b Hall elements 63a, 63b, 64a, 64b Hall elements 65 ~ 69 Magnetic convergence plate 71 ~ 74 Hall element 76 ~ 79 Magnetic convergence plate 81 ~ 84 Hall element 85 Magnetic Convergent Plate 90 recess 91 heater 92 ~ 95 Temperature sensor 102 Sensor placement space 113 Temperature sensor 115 A / D converter 116 Correction calculation unit 117 Correction value storage 118 Azimuth calculation unit