JP3294707B2 - Gas rate sensor with built-in acceleration sensor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas rate sensor with a built-in acceleration sensor in which an acceleration sensor and an angular velocity sensor are integrally formed by using a semiconductor manufacturing process.

[0002]

2. Description of the Related Art In a conventional multi-axis acceleration sensor, a heating resistor and a temperature-sensitive resistor formed of a thin wire such as platinum or tungsten are fixed to a support provided in a case, and gas is sealed in the case. Sealed structures are known.

In such a conventional multi-axis acceleration sensor, a heating resistor is disposed at the center of a space in a case, and the heating resistor is arranged in a multi-axis (for example, X, Y and Z) directions orthogonal to each other about the heating resistor. A pair of temperature-sensitive resistors are arranged, and a change in temperature distribution of heat generated by the heating resistor due to the action of acceleration is detected as a change in a resistance value generated in each of the pair of temperature-sensitive resistors. The action direction of the acceleration can be detected from the arrangement of the pair of temperature-sensitive resistors for detecting the magnitude of the corresponding acceleration and the change in the resistance value from the change in the acceleration.

Further, as disclosed in Japanese Patent Application Laid-Open No. 63-118667, "3D acceleration sensor", a semiconductor substrate is provided with a mass part and a beam part supporting the mass part, and a resistance part is formed in the beam part. Then, the one-dimensional acceleration sensor configured to bend the beam portion by the action of the acceleration and to change the resistance value of the resistance portion corresponding to the deflection of the beam portion is mounted on three surfaces (X, Y, Z) of the cubic block orthogonal to each other. ) To form a three-dimensional acceleration sensor.

On the other hand, in a conventional multi-axis gas rate sensor, a heat wire thermal resistance element is formed by a thin wire of platinum or tungsten, and a plurality of heat wire thermal resistance elements are mounted on a support provided in a case in pairs. The arrangement arranged to detect an angular velocity in a desired direction is known.

[0006]

In a conventional multi-axis acceleration sensor, a heating resistor and a plurality of pairs of temperature-sensitive resistors are mounted on a case support, and a plurality of pairs of temperature-sensitive resistors (for example,
There is a problem that it takes time to arrange the temperature-sensitive resistors and adjust the sensitivity, such as axis alignment in the X, Y, and Z directions, and adjustment of the distance from the heating resistor to each of the pair of temperature-sensitive resistors.

[0007] Further, since there is a sensitivity variation between sensors due to the variation of the heating resistor and the temperature-sensitive resistor, there is a problem that it is essential to select the heating resistor and the temperature-sensitive resistor and to individually adjust the sensor in manufacturing. .

Further, the three-dimensional acceleration sensor disclosed in Japanese Patent Application Laid-Open No. 63-118667 has a structure in which three one-dimensional acceleration sensors formed on a semiconductor substrate are mounted on a cubic block. There is a problem that it takes time to align the axes.

On the other hand, a conventional multi-axis gas rate sensor is
Because of the structure in which the heat-resistance elements of discrete components composed of thin wires of platinum or tungsten are attached to the support, the distance between the heat-flow resistance elements and the central axis of the gas flow must be determined. There is a problem of positional accuracy such as a direction (vertical) with respect to the direction, and a problem that time is required for adjustment work for guaranteeing the positional accuracy.

A conventional multi-axis gas rate sensor is
Since the heat wire heat-sensitive resistance element, the support, and the case are composed of discrete components, there is a problem that it is necessary to select characteristics (resistance value and temperature property) of each heat wire heat-sensitive resistance element and pairing.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to integrate a multi-axis acceleration sensor and a multi-axis gas rate sensor by using a semiconductor manufacturing process, and to provide detection accuracy and reliability. An object of the present invention is to provide a gas rate sensor with a built-in acceleration sensor that is highly operable and easy to use.

[0012]

In order to solve the above-mentioned problems, a gas rate sensor with a built-in acceleration sensor according to the present invention is provided.
A sealed space in which a predetermined gas is sealed, and a heating resistor and a temperature-sensitive resistor which are arranged in the sealed space and heat the gas to form a temperature distribution in the sealed space are provided. The sensor has an acceleration sensor that detects a change in temperature distribution in the enclosed space caused by the temperature sensor, a gas flow path, and a heat wire resistor placed in the gas flow path, and responds to the action of angular velocity The heat wire resistor has a gas rate sensor for detecting the deflection of the gas flow generated by the heating.
Gas rate sensor with built-in speed sensor
The gas inlet of the gas rate sensor and the gas
Above the space forming the upper half and the enclosed space of the acceleration sensor
The space that forms the half is formed using the semiconductor manufacturing process
And configure a gas rate sensor on the other semiconductor substrate
Space, heat wire bridge and heat wire resistor
Space that forms connection leads, pads, and acceleration sensor
, Heating resistors, temperature-sensitive resistors, and pads
And then bond these two semiconductor substrates together.
And are integrally formed.

In addition, the acceleration sensor built-in gas according to the present invention is provided.
The slate sensor has a sealed space filled with a predetermined gas,
It is placed in this enclosed space and heats the gas to
Heating resistor and temperature-sensitive resistor that form a temperature distribution
Temperature in the enclosed space generated in response to the action of acceleration.
An acceleration sensor that detects a change in the degree distribution with a temperature-sensitive resistor,
Gas flow path and heat wire arranged in this gas flow path
Gas generated in response to the action of angular velocity
Gas rate detector that detects the deflection of the flow with a heat wire resistor
Gas rate sensor with a built-in acceleration sensor
And two semiconductor substrates corresponding to the gas rate sensor
And two semiconductor substrates corresponding to the acceleration sensor
Each is composed of the same substrate and forms a pair of heat wire resistors.
Another two semiconductor substrates to be formed and a pair of temperature-sensitive resistors
Two other semiconductor substrates to be formed on the same substrate
Consists of two semiconductor substrates and two other semiconductor substrates
Four semiconductor substrates are stacked in one direction and bonded together.
A gas rate sensor and a three-axis gas acceleration sensor
It is characterized by being embodied.

Furthermore, an acceleration sensor which constitutes the acceleration sensor incorporated gas rate sensor according to the present invention, a heating resistor disposed in the center of the closed space, Re'll were disposed opposite to the heating element resistor in multiaxial directions It is characterized by comprising a pair of temperature sensitive resistors.

Further, the angular velocity sensor which constitutes the acceleration sensor incorporated gas rate sensor according to the present invention, a pair of heat wire thermal resistor Re respectively'll disposed in opposite to the multi-axial to the central axis of the gas flow It is characterized by having done.

Furthermore, the gas enclosed in the enclosed space of the acceleration sensor constituting the acceleration sensor incorporated gas rate sensor according to the present invention, low thermal conductivity, characterized in that it is a pressurized gas.

[0017]

A gas rate sensor with a built-in acceleration sensor according to the present invention is a semiconductor device comprising a sealed space, a heating resistor and a temperature-sensitive resistor constituting an acceleration sensor, and a gas flow path and a heat wire resistor constituting an angular velocity sensor. Since the manufacturing masks are shared on the same number of semiconductor substrates using the process, the acceleration sensor and the angular velocity sensor can be integrated.

Further, the acceleration sensor and the angular velocity sensor constitute the acceleration sensor incorporated gas rate sensor according to the present invention, the closed space constituting an acceleration sensor using a semiconductor manufacturing process, a heating resistor and the temperature sensitive resistor, the angular velocity Since the gas flow path and the heat wire resistor constituting the sensor are formed, the respective components can be easily formed, and the arrangement can be realized with high accuracy, so that the acceleration sensor and the angular velocity sensor can be made multi-axial. it can.

Furthermore, the acceleration sensor and the angular velocity sensor constitute the acceleration sensor incorporated gas rate sensor according to the present invention, the heating resistor on the same semiconductor substrate or the same production lot of the semiconductor substrate, the temperature sensitive resistors, the heat wire resistance , The pair characteristics such as the deviation of each resistor and the temperature characteristic are guaranteed. In particular, the deviation of the specific resistance of the paired resistors can be reduced, so that a highly accurate sensor can be realized.

Further, the acceleration sensor constituting the gas rate sensor with the built-in acceleration sensor according to the present invention uses a pressurized gas having low thermal conductivity as the gas to be sealed, so that the temperature distribution formed in the closed space is reduced. Can be set large, and a highly sensitive sensor can be realized.

[0021]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a configuration diagram of an embodiment of a gas rate sensor with a built-in acceleration sensor according to the present invention. In this embodiment, 2
A single-axis gas type acceleration sensor and a single-axis gas rate sensor are integrally formed on a semiconductor substrate.

In FIG . 1, a gas rate sensor 1 with a built-in acceleration sensor comprises a semiconductor substrate 2 and a semiconductor substrate 3. The semiconductor substrate 2 has a gas inlet 2A vertically penetrating the substrate to be a part of the gas rate sensor unit 4 using a semiconductor manufacturing process such as etching, and a space having a predetermined width from the bottom surface of the substrate. , A space 2B forming the upper half of the gas flow path 6 and a space 2C forming the upper half of the sealed space 7 of the acceleration sensor 5.

The semiconductor substrate 3 is formed on the semiconductor substrate 3 by using a semiconductor manufacturing process in which deposition and etching are repeated a plurality of times.
The space portion 3A, the heat wire bridge 3B, and the heat wire resistors H _Wl , H _Wr , which constitute the gas rate sensor portion 4,
Connection leads and pads (not shown) to the heat wire resistor, the space 3C constituting the acceleration sensor unit 5, the heating resistor H, the temperature sensing resistors X1, X2, Y1, Y2, the heating resistor and the temperature sensing resistor. The pad 10 and the like are formed.

[0024] Gas rate sensor part 4 of the heat wire bridge 3B, and the bridge (not shown) of the acceleration sensor section 5 an etching process is formed on the surface of the semiconductor substrate 3, the lower side of each of the bridge space 3A and It constitutes a part of the space 3C. Heat wire resistors H _Wl and H _Wr are formed on the surface of the heat wire bridge 3B, and heat generating resistors H and temperature sensitive resistors X1, X2, Y1, and Y2 are formed on the surface of the bridge (not shown).

The heat wire resistors H _Wl , H _Wr , the heating resistor H, and the temperature sensitive resistors X 1, X 2, Y 1, and Y 2 form conductor portions by vapor deposition or crystal growth of a metal such as platinum or tungsten. Each resistor is formed by performing an etching process based on the fine pattern diagram set on the manufacturing mask. Note that the heat wire resistors H _Wl , H _Wr , the heating resistor H, and the temperature sensitive resistors X1, X2, Y1, and Y2 form resistors having only different resistance values, and therefore, must be formed simultaneously in the same process. Can be.

The heat wire resistors H _Wl and H _Wr are arranged at the middle of the gas flow path 6 formed by the space 2B of the semiconductor substrate 2 and the space 3B of the semiconductor substrate 3 in the Z-axis direction. , The central axis of the gas flow F _Y flowing in the Y-axis direction is symmetrical,
Since the gas rate sensor 1 with a built-in acceleration sensor is mounted on a moving body (vehicle or the like) and moves in the Y-axis direction because it is disposed so as to face the X-axis direction, the horizontal direction (yaw direction) with the Z-axis as a rotation axis. Can be configured as a one-axis angular velocity sensor that detects the angular velocity ω _X of.

[0027] The heating resistor H and the temperature sensitive resistor X1, X
2, Y1 and Y2 are arranged on the same XY plane in the Z-axis direction of the sealed space 7 formed by the space 2C of the semiconductor substrate 2 and the space 3C of the semiconductor substrate 3, and the heating resistor H is provided. X-
A pair of temperature-sensitive resistors X1, X2 and a temperature-sensitive resistor Y are formed so as to be located at substantially the center on the same plane Y and symmetrically opposing the heating resistor H in the X-axis and Y-axis directions.
Since the first and second Y2 are arranged, a two-axis acceleration sensor that detects acceleration (G) acting in the X-axis and Y-axis directions can be configured.

[0028] After the fabrication of the semiconductor substrate 2 and the semiconductor substrate 3 is completed, the low pressurized gas thermal conductivity such as nitrogen gas or argon gas sealed in the closed space 7, overlapping the two substrates in the Z-axis direction The gas rate sensor 1 with the built-in acceleration sensor is configured by being bonded together. The semiconductor substrate 3 is configured to have a larger size than the semiconductor substrate 2 in order to arrange the pads 10 for external connection.

[0029] Thus, the acceleration sensor incorporated gas rate sensor 1, by adopting the production mask and microfabrication technology of a semiconductor manufacturing process, a heat wire resistance H _Wl, H _Wr, heating resistor H, the temperature sensitive resistor Body X1, X
2, Y1, Y2, and the positions and dimensions of the space portions 2B, 2C, 3B, 3C and the like constituting the gas flow path 6 and the closed space 7 can be formed with high precision. An accurate gas rate sensor unit 4 and gas type acceleration sensor unit 5 that do not require adjustment can be configured.

The heat wire resistors H _Wl , H _Wr ,
The heating resistor H and the temperature-sensitive resistors X1, X2, Y1, and Y2 are:
Since H _Wl and H _Wr are formed on the semiconductor substrate 3,
The pair of resistors X1 and X2, Y1 and Y2 each have excellent pairing properties such as resistance deviation and temperature characteristics, and the accuracy of the resistance ratio is extremely high. Therefore, it is stable by detecting the angular velocity and acceleration by the resistance ratio. Output is obtained.

[0031] Next, the operation of the acceleration sensor incorporated gas rate sensor part 4 of the gas rate sensor 1 and the gas-type acceleration sensor unit 5. The gas rate sensor unit 4
A pair of heat wire resistance H _Wl, with the H _Wr, disposed opposite to the vertical (X-axis) direction to the central axis of the gas flow F _Y (Y-axis), the acceleration sensor built in the Z-axis as a rotation axis An angular velocity ω _X acting on the gas rate sensor 1 is detected. For example, when the gas rate sensor 1 with a built-in acceleration sensor is mounted on a vehicle and is moving in the Y-axis direction, the angular velocity acting on the yaw (direction) can be detected. When the angular velocity in the yaw direction acts, the Coriolis force acts and the gas flow F
_Y is deflected and the balance between the gas amounts hitting the heat wire resistors H _Wl and H _Wr is lost, and the heat wire resistor H
_Wl, the resistance value of the H _Wr is changed, H _wl, by detecting the resistance value deviation of H _Wr, can detect the magnitude and direction of the yaw direction angular velocity.

The gas type acceleration sensor unit 5 includes a closed space 7
A heating resistor H, temperature-sensitive resistors X1, X2, Y1, and Y2 that detect acceleration in two-axis (XY) directions are disposed therein, and are pressurized with low thermal conductivity such as nitrogen or argon. Gas is enclosed.

An external power supply (voltage source or current source) is applied to the heating resistor H, the gas in the sealed space 7 is heated by Joule heat, and a temperature having a large temperature gradient inversely proportional to the distance from the heating resistor H. A distribution is formed. A pair of temperature sensitive resistors X
1 and X2, and the pair of temperature-sensitive resistors Y1 and Y2 are arranged at equal intervals in the X-axis and Y-axis directions from the heating resistor H, respectively. In the state where does not act, the temperature is in the same temperature environment, the temperature balance is maintained, and no acceleration is detected.

When the acceleration (G) acts in the X-axis direction from the temperature balance state, for example, the temperature distribution in the closed space 7 moves in the direction opposite to the direction in which the acceleration (G) acts, and the temperature distribution and the temperature-sensitive resistor X1 change. The temperature balance of the temperature-sensitive resistor X2 is lost, the temperature of the temperature-sensitive resistor X1 increases, and the temperature of the temperature-sensitive resistor X2 decreases. When the temperature of the temperature-sensitive resistor X1 rises, the temperature-sensitive resistor X
1 increases, while the temperature of the temperature-sensitive resistor X2 decreases and the resistance of the temperature-sensitive resistor X2 decreases, so that the acceleration (G) is detected with a value corresponding to the resistance deviation.
The magnitude of the acceleration (G) can be detected from the value corresponding to the resistance deviation, and the action direction of the acceleration (G) can be detected from the sign (±) of the resistance deviation.

[0035] Similarly, when acceleration acts (G) is in the Y-axis direction, collapsing temperature balance of the acceleration (G) the temperature sensitive resistor disposed in a direction acts Y1, Y2, corresponding to each of the resistance deviation The acceleration (G) can be detected from the obtained value and the sign.

[0036] Thus, the acceleration sensor incorporated gas rate sensor 1 includes a gas rate sensor for detecting an angular velocity omega _X yaw (horizontal) direction 1 axes and the rotation axis of the Z axis, two axes of X-axis and Y-axis A gas-type acceleration sensor that detects acceleration (G) acting in the direction can be integrally formed.

FIG . 2 is a block diagram showing another embodiment of the gas rate sensor with a built-in acceleration sensor according to the present invention. In this embodiment,
A three-axis gas type acceleration sensor and a one-axis gas rate sensor are integrally formed on a semiconductor substrate. 2, the gas rate sensor 11 with a built-in acceleration sensor differs from the configuration of FIG. 1 only in that a single-axis piezo-type acceleration sensor for detecting acceleration (G) acting in the Z-axis direction is added to the acceleration sensor unit 5.

The piezo-type acceleration sensor forms a space 3D by etching the side surface 3 and the lower side while leaving the mass portion 8 by etching on the semiconductor substrate 3 and forming a space 3D at the connection portion between the mass portion 8 and the semiconductor substrate 3. Forms a movable portion (beam portion) thinner than the mass portion 8, and corresponds to a force (product of mass and acceleration) acting on the mass portion 8 when acceleration (G) in the Z-axis direction acts. The beam section is configured to bend (strain).

The piezo element Z is formed by a semiconductor process such as evaporation.
The acceleration (G) acting in the Z-axis direction by forming the movable portion (beam portion) 1 and Z2 and detecting the deflection (strain) of the movable portion (beam portion) by the resistance change of the piezo elements Z1 and Z2. Can be detected. It should be noted that a capacitive acceleration sensor may be used instead of the piezo acceleration sensor.

FIG . 3 shows a circuit diagram of the angular velocity detecting circuit of the one-axis gas rate sensor. A pair of heat wire resistors H _Wl (resistance R _L ) and H _Wr (resistance R _R ), reference resistances R _F1 and R _{F2 form} a resistance bridge circuit, and are driven by a power supply (constant current source I _O ) to perform DC after obtaining a voltage output V _Z1, V _Z2, the output V _Z1, V
_The deviation (V) is determined by _Z2 using a comparator composed of an operational amplifier OP-1 or the like.
_Z1 -V _Z2) to obtain the angular velocity detection output V _O1 corresponding to configuration.

When the reference resistances R _F1 and R _F2 are set to the same value, an output proportional to the resistance deviation (R _R -R _L ) is obtained as the angular velocity detection output V _O1 , and the angular velocity acting in the yaw direction can be detected. Can be. Note that the magnitude of the angular velocity is the detection output V _O1
, And the direction of the angular velocity is obtained from the sign of the detection output V _O1 .

FIG . 4 shows an acceleration detection circuit of a three-axis acceleration sensor. (A) is a heating resistor drive circuit diagram, (b) is an acceleration detection circuit diagram in the X-axis direction, (c) is an acceleration detection circuit diagram in the Y-axis direction, and (d) is an acceleration in the Z-axis direction. FIG. 4 shows a detection circuit diagram. (A) to (d) show an example in which the drive power supply is constituted by a current source (IO), but may be constituted by a voltage source ( _VO ).

[0043] (a) heating resistor driving circuit shown in FIG supplies current source (I _O) to the resistance R of the heating resistor H (I _O ²
* R) Generates Joule heat corresponding to the power.

[0044] (b) acceleration detecting circuit of the X-axis direction shown in the figure, the temperature sensitive resistors X1 (resistance R1), the temperature sensitive resistor X2 (resistance R2), constitute a resistor bridge circuit with a standard resistor Ro1, Ro2 , The bridge output voltage V via the differential amplifier A _X
A deviation V _OX (V _X1 −V _X2 ) based on _{X 1} and V _X2 is output, and a detection output corresponding to the acceleration (G) acting in the X-axis direction is obtained.

[0045] (b) Fig., (C) FIG. Similarly, the differential amplifier A _Y constitute a resistor bridge circuit, and A _Z a through each bridge output voltage V _Y1 and V _Y2, the bridge output voltage V _Z1 and deviations based on V _Z2 V _OY (V _Y1 -
V _Y2 ) and V _OZ (V _Z1 −V _Z2 ) are output, and a detection output corresponding to the acceleration (G) acting in the Y-axis direction or the Z-axis direction is obtained.

[0046] Subsequently, the three-axis gas rate sensor and 3
The structure of a gas rate sensor with a built-in acceleration sensor having a gas type acceleration sensor of the axis will be described. FIG. 5 shows a configuration diagram of a two-axis gas rate sensor. In FIG. 5, a biaxial gas rate sensor 21 is composed of semiconductor substrates 22 to 25 and includes semiconductor substrates 22 and 24 corresponding to the gas rate sensor unit 4 of the gas sensor 11 with a built-in acceleration sensor shown in FIG. , And a four-layer structure by adding semiconductor substrates 23 and 25 forming a pair of heat wire resistors H _WU and H _WD arranged vertically in the Z-axis direction.

[0047] Heat wire bridge 23A of the semiconductor substrate 23, 25, 25A, and heat wire resistance H _WU, H _WD is formed in a similar manner using already a semiconductor manufacturing process such as the etching and deposition that described. After the semiconductor substrates 22 to 25 are formed, they are overlapped and bonded in the Z-axis direction, so that the Z-axis and the X-axis are used as rotation axes.
The angular velocities ω _X and ω _{Z of the} shaft can be detected.

Further , in order to constitute an angular velocity sensor having the Y axis as a rotation axis, a gas flow path for flowing the gas flow FX in the X axis direction and a pair of heat wire resistors in the Z axis direction are required. The gas rate sensor 21 may be additionally provided in the same manner as the two-axis gas rate sensor 21 described above. The configuration of the three-axis gas rate sensor is shown in FIG.

FIG . 6 shows a configuration diagram of a three-axis gas type acceleration sensor. 6, a three-axis gas type acceleration sensor 31 is shown.
Is composed of a semiconductor substrate 32 to a semiconductor substrate 35, and FIG.
A pair of temperature-sensitive resistors Z1 and Z2 disposed vertically on the semiconductor substrate 32 and 34 corresponding to the acceleration sensor unit 5 of the gas rate sensor 1 with a built-in acceleration sensor shown in FIG.
Is different in that a four-layer structure is added by adding semiconductor substrates 33 and 35 for forming the semiconductor substrate.

The temperature-sensitive resistors Z1 and Z2 of the semiconductor substrates 33 and 35 are formed in the same manner by using the above-described semiconductor manufacturing process such as etching and vapor deposition. After the formation of the semiconductor substrates 32 to 35, the acceleration (G) acting on the three axes (XYZ) can be detected by laminating and bonding in the Z-axis direction.

The semiconductor substrates 22 to 25 shown in FIG . 5 and the semiconductor substrates 32 to 35 shown in FIG. 6 are constituted by the same substrate, so that four semiconductor substrates are laminated in the Z-axis direction and bonded together. A gas rate sensor with a built-in acceleration sensor in which a rate sensor and a three-axis gas type acceleration sensor are integrated can be configured.

FIG . 7 is a configuration diagram of a gas rate sensor with a built-in three-axis acceleration sensor according to the present invention. In FIG.
The gas rate sensor 41 with a built-in triaxial acceleration sensor includes a triaxial gas rate sensor unit 46 and a triaxial gas type acceleration sensor unit 43. The three-axis gas rate sensor unit 46
An X-axis direction gas passage 49 is provided in the semiconductor substrate 42 in addition to the Y-axis direction gas passage 48 already described. In the Y-axis direction gas flow path 48, a pair of heat wire temperature sensitive resistors Y ₁ and Y ₂ for detecting yaw direction angular velocity and a pair of heat wire temperature sensitive resistors for detecting pitch direction angular velocity described in FIG. P ₁ ,
The P ₂ is provided, X heat wire temperature-sensitive resistor of the pair of roll direction for angular velocity detection in the axial direction the gas flow path 49 R _O1, R _O2
Are provided facing each other in the Z-axis direction.

From the gas inlet 47 to the Y-axis direction gas passage 48
By simultaneously supplying the gas jets F _Y and F _X to the gas flow channel 49 in the X-axis direction, the yaw direction (Z-axis rotation), the pitch direction (X-axis rotation) and the roll direction (Y-axis rotation) The acting angular velocities ω _X , ω _Z , ω _Y can be detected simultaneously and independently.

On the other hand, the three-axis gas-type acceleration sensor unit 43
As in the case of the three-axis acceleration sensor 31 already described with reference to FIG. 6, a gas 45 such as nitrogen gas or argon gas is pressurized and sealed in a closed space 44 in a semiconductor substrate 42, and the XYZ A pair of temperature-sensitive resistors x ₁ , x ₂ , y ₁ , y ₂ , z ₁ , and z ₂ opposed to each other in three axial directions are arranged, and accelerations (G) acting on three axes are simultaneously and independently detected. can do.

[0055]

As described above, the gas rate sensor with a built-in acceleration sensor according to the present invention includes a sealed space, a heating resistor and a temperature-sensitive resistor constituting an acceleration sensor, a gas flow path constituting an angular velocity sensor, and The heat wire resistor is formed on the same number of semiconductor substrates by using a semiconductor manufacturing process and sharing a manufacturing mask, and the acceleration sensor and the angular velocity sensor can be integrally configured, so that the sensor can be economically combined. be able to.

Further, the gas rate sensor with a built-in acceleration sensor according to the present invention includes a sealed space, a heating resistor and a temperature-sensitive resistor constituting an acceleration sensor using a semiconductor manufacturing process, a gas flow path constituting an angular velocity sensor, and Since the heat wire resistor and the heat wire resistor are formed, the respective components can be easily formed, and the arrangement can be realized with high accuracy, so that the acceleration sensor and the angular velocity sensor can be easily made multi-axial.

[0057] Furthermore, the acceleration sensor and the angular velocity sensor constitute the acceleration sensor incorporated gas rate sensor according to the present invention, the heating resistor on the same semiconductor substrate or the same production lot of the semiconductor substrate, the temperature sensitive resistors, the heat wire resistance , The pair characteristics such as the deviation of each resistor and the temperature characteristic are guaranteed. In particular, the deviation of the specific resistance of the paired resistors can be reduced, so that a highly accurate sensor can be realized.

Further , the acceleration sensor constituting the gas rate sensor with a built-in acceleration sensor according to the present invention uses a pressurized gas having low thermal conductivity as the gas to be sealed, so that the temperature distribution formed in the enclosed space is reduced. Can be set large, and a highly sensitive sensor can be realized.

[0059] Thus, the detection accuracy and high reliability, it is possible to provide an acceleration sensor incorporated gas rate sensor of the easy-to-use multi-axis.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a gas rate sensor with a built-in acceleration sensor according to the present invention.

FIG. 2 is a configuration diagram of another embodiment of the gas rate sensor with a built-in acceleration sensor according to the present invention.

FIG. 3 is a circuit diagram of an angular velocity detection circuit of a one-axis gas rate sensor.

FIG. 4 is an acceleration detection circuit of a three-axis acceleration sensor.

FIG. 5 is a configuration diagram of a two-axis gas rate sensor.

FIG. 6 is a configuration diagram of a three-axis gas acceleration sensor.

FIG. 7 is a configuration diagram of a gas rate sensor with a built-in three-axis acceleration sensor according to the present invention.

[Explanation of symbols]

1,11,41 ... gas rate sensor with built-in acceleration sensor
2, 3, 42: semiconductor substrate, 2A, 47: gas inlet,
2B, 2C, 3A, 3C, 3D: space, 3B: heat wire bridge, 4, 46: gas rate sensor, 5,
43: acceleration sensor unit, 6, 48, 49: gas flow path,
7, 44: closed space, 8: mass part, 9: piezo element, 1
0: pad, H _Wl , H _Wr , H _WU , H _WD : heat wire resistor, H: heating element, X1, X2, Y1, Y2, Z
1, Z2: temperature-sensitive resistor.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-369481 (JP, A) JP-A-3-176669 (JP, A) JP-A-2-55165 (JP, A) 10871 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01P 9/00 G01P 15/12 G01P 15/02

Claims (5)

(57) [Claims] 1. A closed space in which a predetermined gas is sealed, and a heating resistor and a temperature-sensitive resistor disposed in the closed space and heating the gas to form a temperature distribution in the closed space. An acceleration sensor for detecting, by the temperature-sensitive resistor, a change in temperature distribution in the closed space generated in response to the action of acceleration, a gas flow path, and a heat wire resistor disposed in the gas flow path A gas rate sensor with a built-in acceleration sensor having a gas rate sensor for detecting the deflection of the gas flow generated in response to the action of the angular velocity by the heat wire resistor.
A Tosensa, gas inlet of the gas rate sensor part on one semiconductor substrate
Port and the space forming the upper half of the gas flow path and the acceleration
The space that forms the upper half of the enclosed space of the temperature sensor is a semiconductor
It is formed using a manufacturing process, and the other semiconductor substrate forms an empty space constituting the gas rate sensor.
Contact with the space, heat wire bridge and heat wire resistor
Spaces for connecting leads and pads and the acceleration sensor unit
Parts, heating resistors, temperature sensitive resistors, and pads
A gas rate sensor with a built-in acceleration sensor, wherein the gas rate sensor is formed using a process, and the two semiconductor substrates are bonded to each other . 2. A sealed space in which a predetermined gas is sealed, and a heating resistor and a temperature-sensitive resistor disposed in the sealed space and heating the gas to form a temperature distribution in the sealed space. An acceleration sensor for detecting, by the temperature-sensitive resistor, a change in temperature distribution in the closed space generated in response to the action of acceleration, a gas flow path, and a heat wire resistor disposed in the gas flow path A gas rate sensor with a built-in acceleration sensor having a gas rate sensor for detecting the deflection of the gas flow generated in response to the action of the angular velocity by the heat wire resistor.
Heat sensors, two semiconductor substrates corresponding to the gas rate sensor unit
And two semiconductor substrates corresponding to the acceleration sensor unit.
The other two halves , each formed of the same substrate, forming a pair of the heat wire resistors.
Another two forming a conductor substrate, a pair of front Stories temperature sensitive resistor
Each of the semiconductor substrates is composed of the same substrate, and the two
A semiconductor substrate and four other semiconductor substrates
Semiconductor substrates are stacked in one direction and bonded together.
And a 3-axis gas type acceleration sensor
A gas rate sensor with a built-in acceleration sensor. 3. The acceleration sensor comprises: a heating resistor disposed in the center of the enclosed space; and a pair of temperature-sensitive resistors disposed in a multiaxial direction in opposition to the heating resistor. The gas rate sensor with a built-in acceleration sensor according to claim 1 or 2, wherein the gas rate sensor has a built-in acceleration sensor. 4. The gas rate sensor according to claim 1, wherein each of said gas rate sensors comprises a pair of heat-wired heat-sensitive resistors arranged in a multiaxial direction so as to face a central axis of a gas flow.
Or a gas rate sensor with a built-in acceleration sensor according to 2 . Wherein said gas to be sealed in the sealed space of the acceleration sensor, low thermal conductivity, an acceleration sensor built gas rate sensor of claim 1, wherein it is pressurized gas .