JPH0972805A - Semiconductor sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the characteristics of sensor, including the nonlinearity thereof, while enlarging the measuring range thereof by feeding the amplified output from a signal processing means back to a detection element and then amplifying the output from the detection element. SOLUTION: A dummy diffused resistance 20 having resistance identical to that of a gauge resistor 22 is formed on a substrate 1 and a neutral voltage, equal to about 1/2 of an exciting voltage Ex , is applied to a positive terminal of an amplifier 101. Since a same common voltage Eb is applied to a regative terminal 73, e=0 and an output voltage Eo =0 is produced. When a sensor input is applied, resistance of the resistor 22 is varied and the voltage (e) appearing at the positive terminal of amplifier 101 is amplified to Eo . That voltage is applied to a shield film 62 on the detector element itself such that variation in the resistance of detector element is canceled thus bringing the voltage (e) to zero through feedback control. Since the sensor is operated in such range as variation in the resistance of detector element is low for the input amount, the nonlinear error of sensor is prevented from increasing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for improving the characteristics of a small sensor using a resistor as a detecting element, and in particular, the potential on the detecting element is controlled and maintained at a predetermined value to improve nonlinearity and temperature influence, In addition, the present invention relates to a semiconductor sensor that eliminates the influence of the external atmosphere and improves stability.

[0002]

2. Description of the Related Art FIG. 17 shows an example of a conventional pressure sensor. Reference numeral 1 is a semiconductor substrate, and a gauge resistor 22 as a detection element is diffused and formed on a part of the diaphragm portion 12. Two
Is a fixed plate made of glass and is electrostatically bonded to the semiconductor substrate 1. Reference numeral 3 is a metal reinforcing plate having pressure guiding holes, which is adhered to the fixing plate 2. The diaphragm portion 12 is deformed by the input pressure, and the resistance of the gauge resistor 22, which is the detection element, changes due to the piezoresistive effect. The value of input pressure is detected and measured from this amount of resistance change.

[0003]

The semiconductor sensor is characterized by being sensitive to various measured quantities and capable of obtaining a large output change, but has a drawback that the output change is non-linear with respect to the input quantity. For example, in the case of a piezoresistive pressure sensor, a large resistance change can be obtained depending on the pressure, but since the non-linear error is large, it is necessary to correct this with a separate circuit to achieve 0.1% class accuracy. It was

Further, there is a problem that the output is affected by a change in ambient temperature.

Further, there is a problem that the output and sensitivity of the sensor are easily influenced by the influence of the surface potential variation caused by the ambient environment atmosphere.

The present invention improves the characteristics of such a semiconductor sensor and achieves higher accuracy.

That is, an object of the present invention is to improve the characteristics of a sensor that uses resistance or capacitance as a detection element, to improve the non-linearity and to expand the measurement range.

Another object of the present invention is to improve the temperature effect and to reduce the offset voltage of the bridge.

Still another object of the present invention is to provide a sensor which is free from the influence of the external atmosphere and has good stability.

[0010]

A first feature of the present invention for achieving the above object is to provide a semiconductor substrate having one conductivity type and a conductivity type formed on the semiconductor substrate and different from the semiconductor substrate. A semiconductor sensor having a mold and changing its output in response to a change in input such as pressure, and a signal processing means for amplifying the output from the detecting element to a predetermined value. The output is fed back to the detection element, and the output of the detection element after the feedback is amplified by the signal processing means to be a sensor output.

A second feature of the present invention is that a semiconductor substrate having one conductivity type and a detection element having a conductivity type different from that of the semiconductor substrate formed in a thin portion obtained by processing a part of the semiconductor substrate. Group, a low resistance current supply terminal extending from the thin portion to the thick portion, a wiring film for connecting a plurality of resistors to a bridge circuit, and a shield thin film formed on the detection element group via an insulating film A semiconductor sensor consisting of the semiconductor substrate is connected to a high potential of a power source, the shield thin film on the detection element group is extendedly formed on the thick portion of the semiconductor substrate, and the signal processing circuit is connected via the connecting portion. To provide a control potential.

Furthermore, a third feature of the present invention is that a semiconductor substrate having one conductivity type and a detection having a conductivity type different from that of the semiconductor substrate formed in a thin portion obtained by processing a part of the semiconductor substrate. An element group, a low resistance current supply terminal extending from the thin portion to the thick portion, a low resistance layer for connecting a plurality of resistors to a bridge circuit and the detection element group formed on the detection element group, Is a semiconductor sensor composed of different conductivity type layers, the semiconductor substrate is connected to a high potential of a power source, and a conductivity type layer different from the detection element group formed on the detection element group is extended to form signal processing. It is to connect to the circuit and apply a control potential.

[0013]

According to the present invention, a semiconductor substrate having one conductivity type and a detection element formed on the semiconductor substrate and having a conductivity type different from that of the semiconductor substrate and changing the output in response to an input change such as pressure. And a semiconductor sensor consisting of a signal processing means for amplifying the output from the detection element, the output amplified by the signal processing means is fed back to the detection element, and the detection means after the feedback. By amplifying the output by the signal processing means and using it as the sensor output, it is possible to improve the increase in the nonlinear error of the output change with respect to the input amount.

Further, by controlling and holding the surface potential of the detecting element at a predetermined value, it is possible to control the resistance temperature coefficient and improve the influence of the output and the sensitivity due to the ambient temperature change.

Further, it is possible to improve the reliability of the sensor by stabilizing the characteristics of the sensor by controlling and holding the surface potential of the detecting element at a predetermined value.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

1 to 5 are wiring diagrams, FIGS. 6 and 7 are diagrams for explaining the operating principle, FIGS. 8 to 11 are sensor plane layout diagrams, and FIG. 12 is a sensor cross-sectional configuration diagram. Also, FIGS.
FIG. 4 is a partially enlarged sectional view of a detection element.

FIG. 1, FIG. 7 (a) and FIG. 8 are single block diagrams showing the basic principle of the present invention. Further, the drawings in FIGS. 1 to 5 and FIGS. 8 to 12 correspond to each other.

First, the operating principle of the MOS structure sensor will be described with reference to FIG.

The gauge resistor 22 formed on the semiconductor substrate 1 shown in FIG. 6 (c) is a detecting element whose resistance changes according to pressure, flow rate, temperature, concentration, etc., and its cross-sectional structure is M.
It has an OS structure. Therefore, the power supply 1 of the semiconductor substrate 1
When 5 is set to a constant value, the resistance value changes as shown in FIG. 6B due to the potential E of the shield film 6 formed on the insulating film 9 (oxide film). This is because the depletion layers 23 and 24 are formed by the charges charged on the insulating film 9 as a dielectric, and the effective path of carriers is changed. Further, the temperature coefficient TCR of the resistance is also influenced by the shield potential and can be zero at a certain voltage as shown in the example of FIG.

On the other hand, in the case of the pressure sensor using the conventional gauge resistance, the non-linear error between the input and the output increases as the resistance change in response to the input amount increases as shown in the example of FIG. 7B. It is known to increase.

The present invention intends to improve this point by utilizing the above principle. Basically, as in the embodiment shown in the connection diagram of FIG. 1 or the structural diagram of FIG. 7A, Composed. Next, the details of the present invention will be described. For example, in FIG. 1, since the diffusion resistance 20 which is a dummy resistance is selected to be the same as the resistance of the gauge resistance 22, when there is no sensor input, the + terminal of the amplifier 101 has about ½ of the excitation voltage Ex.
The midpoint voltage is applied. Since the same common voltage Eb is applied to the-terminal 73 as well, e = 0 and the output voltage also becomes Eo = 0. When an input is applied to the sensor, the resistance of the gauge resistor 22 changes, and the voltage e generated at the + input terminal of the amplifier 101 is amplified to Eo. This voltage is applied to the shield film 62 on the detection element itself so that it acts so as to cancel the resistance change of the detection element, and the voltage e is set to zero (actually, e = 0 is not completely, The value is controlled to be a value.) Feedback control is performed. Therefore, since the detection element can be operated in a range in which the resistance change with respect to the input amount is small, it is possible to prevent the non-linear error of the sensor from increasing.

Regarding the temperature characteristic, as shown in FIG. 2, the temperature characteristic is improved by setting the potential of the shield films 60 and 62 to the voltage Es having the resistance temperature coefficient TCR near zero by the power supply 72. be able to. When the gauge resistance 22 and the diffusion resistance 20 are formed and used on the same chip, the temperature coefficient of resistance TCR of both of them should be the same.
The bias voltage Es of the mutual shield films is finely controlled to be the operating point.

Further, in order to stabilize the resistance, it is necessary to maintain the potentials of the both at a constant value. In FIG. 6C, first, when the conductivity type of the semiconductor substrate 1 is n-type and the gauge resistor 22 is p-type, the potential of the semiconductor substrate 1 is set to be reverse biased to secure the insulation of the gauge resistor. The power supply 15 may set the potential higher than the power supply voltage Ex. The operating point is the voltage Es of the shield film,
The resistance change due to the input of the sensor is converted into a voltage signal change e by a half bridge composed of two gauge resistors 20 and 22, which is then amplified by the amplifier 101 to be shielded by the shield film 62.
The output signal voltage Eo is taken out by feeding back so as to cancel the resistance change.

As a method of obtaining a large sensor output as shown in FIGS. 3 and 4, there is a method of forming an active bridge by using two or four gauge resistors. In the case of this method, the operating point is also changed. Acting as Es, at least one shield film potential is adjusted so that the offset voltage of the bridge does not change with temperature.

Further, by holding the shield film 6 at a predetermined potential based on the voltage dependence of the resistance value of FIG. 6B, the influence of foreign ions and charges trapped on the sensor surface is prevented, and the gauge resistance is reduced. It is possible to stabilize the value and eliminate the drift of the bridge output voltage e.

Since the gauge resistor 22 has high sensitivity, the semiconductor substrate 1 and the insulating film 9 and (Al) formed of (SiO ₂ ).
The thermal strain generated by the difference in the coefficient of thermal expansion from the terminal wiring portions 4 and 14 formed in 4 is also detected, and the resistance of the four gauges 2
There is a problem that the offset voltage of the bridge changes due to a difference between the resistance values of 1 and 22. To solve this problem, the dependence of the resistance on the shield film voltage shown in FIG.
As shown in (1), it is possible to cancel the offset voltage of the bridge by controlling the shield film potential Es ₁ of at least one resistance of the bridge to change the resistance value.

Further, when the offset voltage changes due to temperature change, the shield film potential Es ₂ is used so as not to change with temperature by utilizing the shield film voltage dependence of the temperature coefficient of resistance TCR shown in FIG. 6A. Can be controlled to adjust the temperature coefficient of resistance to prevent the offset voltage from fluctuating due to temperature changes.

Next, the specific arrangement of the sensors will be described.

In FIG. 9 in which FIG. 2 is laid out on an actual sensor chip, a diffused resistor 20 having no strain sensitivity is formed in the <100> direction on the same substrate 1 and shielded based on the principle of FIG. 6A. The temperature coefficient of resistance of the membrane 60 is adjusted by adjusting the potential Es of the membrane 60 with the variable power source 72.
The differential input e is designed so that it is not affected by the ambient temperature.

3 and 10 are gauges having two types of strain sensitivity, positive and negative, formed in a direction parallel to the <110> direction on the thin portion 12 as a diaphragm on the semiconductor substrate 1 and in a direction orthogonal thereto. Resistors 21, 22 and amplifiers 101, 102
The following shows an example in which the sensitivity is twice as high as that in the above example.

The operation of the semiconductor sensor of the present invention will be described in detail with reference to FIG. The semiconductor substrate 1 is a silicon single crystal substrate having a (100) crystal orientation, and 21 and 22 are two kinds of gauge resistors formed in the thin portion 12, and the pressure P is applied from the upper surface.
Is added, the resistance of the gauge resistance 21 increases and the resistance of the gauge resistance 22 decreases due to the piezoresistive effect. The effective part of the gauge resistance is the thick part 1 of the board.
Part of the low resistance portion 13 extending to 1 is connected to the terminal wiring portion 4, and two gauge resistors 21 and 22 are connected to a bridge circuit as shown in FIG. 61 and 62 are shield thin films provided on the insulating film 9 so as to cover the gauge resistance,
The wiring film 8 connects the outputs of the amplifiers 101 and 102. When pressure P is applied from the upper surface, the resistance of the gauge resistor 21 increases and the resistance of the gauge resistor 22 decreases. Therefore, the midpoint potential of the bridge circuit changes to positive or negative in response to the pressure P. The output changes ± ΔE.
This voltage is fed back to the shield films 61 and 62, and acts to cancel the unbalanced voltage of the bridge as described above, and rebalances the resistance of the gauge resistors 21 and 22. Therefore, the resistance change due to the pressure shown in FIG. 7B operates in the vicinity of zero where the characteristic is linear, so that the nonlinear characteristic can be improved.

Further, the shield thin films 61 and 62 are formed as shown in FIG.
As described in (a), since it is connected to the potential Es for adjusting the temperature coefficient TCR of the resistance to zero, fluctuations in the output of the bridge can be prevented even if the ambient temperature changes.
By accurately holding the shield film potential Es on the resistor, the influence of extraneous ions or the like is eliminated, so that the output drift of the sensor can be prevented.

FIGS. 4 and 11 show two types of strain-sensitive gauge resistors 21 and 22 and an amplifier 101 which are formed on the thin portion 12 on the semiconductor substrate 1 in a direction parallel to the <110> direction and in a direction orthogonal thereto. , 102, two sets are used, and the operation is the same as that described above, but it is characterized by having a sensitivity four times that of the single configuration example.

FIGS. 5 and 12 show a modification of the present invention, in which the midpoint potential portion of the bridge circuit formed by the two types of gauge resistors 21 and 22 and the dummy diffusion resistor 20 is the amplifier 1 respectively.
It is connected to the inputs of 01 and 102, and is further connected to the amplifier 103 for obtaining a predetermined standard output signal. With such a configuration, it is possible to have a function of transmitting this signal to the outside.

13 to 16 show an example in which the present invention is applied to a pressure sensor having another structure.

FIG. 13A shows a plan view and FIG. 13B shows a sectional view. Semiconductor substrate 1 formed of (100) crystal plane
A thin portion 12 serving as a diaphragm portion is formed from the back surface by an alkali etching method or the like on the back surface, and two sets of gauge resistors 2 having opposite resistance changes due to pressure are formed on the upper surface.
1, 22 are diffused and formed inside the central rigid body 15 in the radial direction and the tangential direction, respectively, and connected to the bridge. The connection points of both gauges are respectively connected to the amplifiers 101 and 102 formed in the vicinity. The outputs of these amplifiers are further connected to the operational amplifier 103, amplified to a predetermined output voltage value Eo, and then taken out from the output terminals 51 to 53 formed in the thick portion 11 of the semiconductor substrate 1. Intermediate amplifier 101,
The output voltage of 102 is a thin film shield 61 formed on the gauge resistors 21 and 22 which are detection elements by the insulating film 8.
It is returned to 62 and acts to restore the resistance change due to pressure.

The central rigid body 15 shown in FIG. 13 (a) has a structure provided to improve the non-linearity due to mechanical factors of pressure-displacement.
Is a central rigid body 15 that occupies a considerable area of the semiconductor substrate 1.
Form on top. The thick portion 11 of the semiconductor substrate 1 is a thick portion formed to adhere to the fixed plate 2. According to this embodiment, not only the non-linearity due to a mechanical factor is improved, but as described above, the feedback causes the resistance change due to the pressure to operate in a linear region, so that the pressure sensor having a wide measurement range is compact. It can be realized with a structure.

FIG. 14 shows a gauge resistor 23 for measuring temperature.
In this example, the signal (1) is amplified and the amplified signal (voltage) is applied to the shield film 61 formed on the gauge resistors 21 and 22 to correct the irregularity of the two resistance changes due to temperature and improve the temperature effect. The gauge resistors 21 and 22 which are detection elements are arranged in the <110> axis direction having a large gauge factor, and the gauge resistors 23 and the amplifiers 101 and 102 (resistances used for the temperature compensation elements) which have a large gauge factor have a small gauge factor <100>. Arrange in the axial direction.

FIG. 15 shows a partially enlarged sectional view of a MOS structure sensor using the gauge resistor 21 as a detecting element. A thin shield thin film 6 is formed on the gauge resistor 21 via an insulating film 9.

Further, the wiring film 8 for connecting the plurality of detection elements formed on the semiconductor substrate 1 needs to have a low electric resistance, and therefore is formed to be relatively thick, for example, 1 μm. On the other hand, the shield film 6 is made as thin as 0.1 μm in order to reduce thermal hysteresis. Furthermore, a contact 14 having a contact with the substrate potential to which the highest potential of the power source is connected is provided.

In order to ensure the stability of the gauge resistor 22 formed on the semiconductor substrate 1, an oxide film (insulating film) is generally formed on the surface thereof to form a MOS structure. Therefore, the resistance value changes depending on the substrate potential and the potential of the shield film 6 formed on the oxide film. This is because the carrier passage is changed by the electric charges on the oxide film as the dielectric. If the substrate has n-type conductivity and p-type resistance, pn
The substrate potential is set to the highest potential of the power supply voltage in order to ensure the insulation of the gauge resistance by reverse biasing the junction.

FIG. 16 shows an example in which an n + layer 65 having an impurity concentration of 10 ¹⁹ / cm ³ or more is formed on the chip surface instead of the shield film 6, so to speak, MSS (Metal-Semicondurcotr-
It is a semicondurcotr structure, and is controlled so that the resistance change of the gauge resistance 21 changed by the input pressure is returned to the original value by returning to the n + layer 65 and applying a voltage. The feature of this embodiment is that since there is no insulating film 9 on the thin portion 12, the deformation due to the bimetal thermal stress with the semiconductor substrate 1 can be prevented. Therefore, even when the thin portion 12 is thinned to 10 μm and a low pressure is measured, the thin portion 12 does not deform due to thermal stress, and thus the linearity and temperature characteristics are good.

The present invention has been described above using various embodiments. According to such embodiments, (1) the non-linear error is reduced, and the measurement range is expanded.

(2) To provide a sensor which is not affected by a change in ambient temperature by applying a potential on the detection element as a bias voltage so that the temperature coefficient of the gauge resistance becomes zero.

(3) The value of the potential on the detection element is controlled to compensate for the bridge offset voltage generated at the time of manufacture due to variations in gauge resistance, thermal strain, assembly strain, and the like.

(4) By controlling and holding the value of the potential on the detection element to a predetermined value, the effect of surface ions and moisture is prevented and the characteristics of the detection element are stabilized. The cause of the drift is that the potential of the oxide film surface fluctuates. However, if the surface potential is stabilized, the drift can be reduced.

The above effect can be obtained.

Further, it is needless to say that by using the semiconductor sensor of the present invention for a pressure transmitter or the like, a transmitter having a wide measurement range and stable characteristics that is not affected by changes in ambient temperature can be realized.

[0050]

As described above, according to the present invention, the gauge resistance formed on the semiconductor substrate is used as a detection element, and after the resistance value change due to the measured amount is amplified to a predetermined voltage, it is fed back to the gauge resistance. Thus, by operating so as to suppress this change in resistance value, the gauge resistance is operated in a region with good linearity. As a result, the non-linear error can be reduced and the measurement range can be expanded.

[Brief description of drawings]

FIG. 1 is a connection diagram showing a basic circuit configuration of the present invention.

FIG. 2 is a wiring diagram showing a circuit configuration with improved temperature characteristics.

FIG. 3 is a connection diagram showing a circuit configuration for obtaining a large sensor output.

FIG. 4 is another wiring diagram showing a circuit configuration for obtaining a large sensor output.

FIG. 5 is a connection diagram showing a circuit configuration for canceling an offset voltage of a bridge.

FIG. 6 is an explanatory diagram of voltage dependence of gauge resistance characteristics for explaining the principle of the present invention.

7A and 7B are a sectional view of a sensor of the present invention and an operation explanatory diagram of a piezoresistive gauge.

FIG. 8 is a sensor layout diagram of FIG. 1 of the present invention.

FIG. 9 is a sensor layout diagram of FIG. 2 of the present invention.

10 is a sensor layout diagram of FIG. 3 of the present invention.

FIG. 11 is a sensor layout diagram of FIG. 4 of the present invention.

12 is a cross-sectional configuration diagram of the sensor of FIG. 5 of the present invention.

FIG. 13 is a structure and wiring diagram of another example implemented in the pressure sensor.

FIG. 14 is a structure and wiring diagram of another example for improving the influence of temperature on the pressure sensor.

FIG. 15 is a partially enlarged sectional view of a MOS structure sensor.

FIG. 16 is a partially enlarged sectional view of the MSS structure sensor.

FIG. 17 is a cross-sectional view showing an example of a conventional pressure sensor and a bridge circuit connection diagram.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate, 2 ... Fixing plate, 3 ... Reinforcing plate, 4 ... Terminal wiring part, 8 ... Wiring film, 9 ... Insulating film, 11 ... Thick part, 12 ...
Thin portion, 13 ... Low resistance portion 21, 22, 23 ... Gauge resistance 51-53 ... Output terminal, 60-62 ... Shield film,
65 ... Shield layer, 71, 72, 73 ... Power source, 101-
103 ... Amplifier.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Sase 882 Ichige, Ichima, Hitachinaka City, Ibaraki Prefecture Hitachi Ltd. Measuring Instruments Division

Claims (10)

[Claims] 1. A semiconductor substrate having one conductivity type, a detection element formed on the semiconductor substrate and having a conductivity type different from that of the semiconductor substrate, the detection element changing an output in response to an input change such as pressure. In a semiconductor sensor comprising a signal processing means for amplifying an output from a detection element, the output amplified by the signal processing means is fed back to the detection element, and the output of the detection element after the feedback is subjected to the signal processing. A semiconductor sensor characterized by being amplified by means to obtain a sensor output. 2. The semiconductor sensor according to claim 1, wherein an insulating film is formed on the detection element, a shield thin film is formed on the insulating film, and an output amplified by the signal processing means is output to the shield thin film. A semiconductor sensor which is fed back, and the output of the detection element after the feedback is amplified by the signal processing means to be a sensor output. 3. The semiconductor sensor according to claim 1, wherein a conductive type layer different from the detecting element is formed on the detecting element, and the output voltage of the signal processing means is fed back to the conductive type layer, A semiconductor sensor, wherein the output of the detecting element after the feedback is amplified by the signal processing means to be a sensor output. 4. The semiconductor sensor according to claim 1, wherein a resistor is formed as the detection element, and a predetermined bias voltage is applied to the resistor in advance, and the bias voltage is the temperature of the resistor. A semiconductor sensor, which is connected and held at a potential near a coefficient of zero. 5. The semiconductor sensor according to any one of claims 1 to 3, wherein a predetermined potential is applied to a shield thin film formed on at least one detection element or a conductive type layer different from the detection element, and at least one detection is performed. A semiconductor sensor characterized by correcting an offset voltage of a bridge formed from a plurality of detection elements by controlling an electric potential applied to the element. 6. The semiconductor sensor according to any one of claims 1 to 3, wherein a pressure detection element, a temperature detection element, and signal processing means corresponding to each of the detection elements are formed on the semiconductor substrate. Of the pressure detection element by applying a predetermined voltage converted by the signal processing means to a shield thin film or a conductive type layer different from the semiconductor substrate, A semiconductor sensor characterized by compensating for temperature characteristics. 7. A semiconductor substrate having one conductivity type, a detection element group formed in a thin portion obtained by processing a part of the semiconductor substrate and having a conductivity type different from that of the semiconductor substrate, and the thin portion to the thick portion. A low resistance current supply terminal extending to the portion, a wiring film for connecting a plurality of resistors to a bridge circuit and a semiconductor sensor comprising a shield thin film formed on the detection element group via an insulating film, The semiconductor substrate is connected to the high potential of the power source, the shield thin film on the detection element group is extendedly formed on the thick portion of the semiconductor substrate, and the signal processing circuit is connected through the connection portion to give a control potential. A semiconductor sensor characterized by. 8. A semiconductor substrate having one conductivity type, a detection element group having a conductivity type different from that of the semiconductor substrate formed in a thin portion obtained by processing a part of the semiconductor substrate, and a thin portion from the thin portion. A low-resistance current supply terminal extending to the portion, a low-resistance layer for connecting a plurality of resistors to a bridge circuit, and a semiconductor sensor formed of a conductive type layer different from the detection element group formed on the detection element group. The semiconductor substrate is connected to a high potential of a power source, a conductive type layer formed on the detection element group different from the detection element group is extended and connected to a signal processing circuit, and a control potential is applied. A semiconductor sensor characterized by. 9. The semiconductor sensor according to claim 1, wherein the direction of the diffusion resistor used for the signal processing means is a crystal direction having a minimum piezoresistance coefficient. 10. The semiconductor sensor according to claim 1, wherein the crystal plane of the substrate is (100).