sensor

Abstract

To provide a sensor capable of improving performances.SOLUTION: A sensor includes a sensor part and a circuit part. The sensor part includes: a first element part containing a first resistive element and a first conductive member; and a second element part containing a second resistive element. The circuit part includes a detection part and a control part. The circuit part can perform a first operation. In the first operation, the control part can control first electric power on the basis of a second signal corresponding to second resistance of the second resistive element. In the first operation, the control part can supply the first electric power to the first conductive member to increase a first temperature of the first element part. In the first operation, the detection part can output a detection value corresponding to a difference between a first signal corresponding to first resistance of the first resistive element in a first state where the first temperature is increased and the second signal.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to sensors.

Background Art

[0002] For example, there are sensors using MEMS (Micro Electro Mechanical Systems) elements or the like. In sensors, improvement of characteristics is desired.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments provide a sensor capable of improving characteristics.

Means for Solving the Problems

[0005] According to an embodiment, a sensor includes a sensor unit and a circuit unit. The sensor unit includes a first element unit including a first resistance element and a first conductive member, and a second element unit including a second resistance element. The circuit unit includes a detection unit and a control unit. The circuit unit is capable of performing a first operation. In the first operation, the control unit can control first power based on a second signal corresponding to a second resistance of the second resistance element. In the first operation, the control unit can supply the first power to the first conductive member to increase a first temperature of the first element unit. In the first operation, the detection unit can output a detection value corresponding to a difference between a first signal corresponding to a first resistance of the first resistance element in a first state where the first temperature has increased and the second signal.

Brief Description of the Drawings

[0006] [Figure 1] Figure 1 is a block diagram illustrating a sensor according to the first embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view illustrating a sensor according to the first embodiment. [Figure 3] Figure 3 is a schematic plan view illustrating a sensor according to the first embodiment. [Figure 4] Figure 4 is a schematic plan view illustrating a sensor according to the first embodiment. [Figure 5] Figures 5(a) to 5(e) are schematic diagrams illustrating the operation of the sensor according to the first embodiment. [Figure 6] Figure 6 is a schematic cross-sectional view illustrating a sensor according to the first embodiment. [Figure 7] Figure 7 is a block diagram illustrating a sensor according to the second embodiment. [Figure 8] Figure 8 is a schematic cross-sectional view illustrating a sensor according to the second embodiment. [Modes for carrying out the invention]

[0007] The embodiments of the present invention will be described below with reference to the drawings. Drawings are schematic or conceptual, and the relationships between the thickness and width of each part, as well as the ratios of the sizes of different parts, are not necessarily identical to those of reality. Even when representing the same part, the dimensions and ratios may be depicted differently in different drawings. In this specification and in each figure, elements similar to those described above are denoted by the same reference numerals with respect to previously shown figures, and detailed explanations are omitted as appropriate.

[0008] (First Embodiment) Figure 1 is a block diagram illustrating a sensor according to the first embodiment. As shown in Figure 1, the sensor 110 according to this embodiment includes a sensor unit 10S and a circuit unit 70.

[0009] The sensor section 10S includes a first element section 11E and a second element section 12E. The first element section 11E includes a first resistive element 11 and a first conductive member 21. The second element section 12E includes a second resistive element 12. As will be described later, the second element section 12E may also include a second conductive member 22. The first element section 11E is included in the first detection element 10A. The second element section 12E is included in the second detection element 10B.

[0010] The circuit unit 70 includes a detection unit 71 and a control unit 72. The circuit unit 70 is capable of performing a first operation. In the first operation, the control unit 72 can control the first power PW1 based on a second signal Sr2 corresponding to the second resistance of the second resistive element 12. In the first operation, the control unit 72 can supply the controlled first power PW1 to the first conductive member 21 to raise the first temperature of the first element unit 11E. In the first operation, the detection unit 71 receives a first signal Sr1 corresponding to the first resistance of the first resistive element 11 in the first state where the first temperature has risen, and a second signal No. S r2 and It is possible to output a detected value Vout corresponding to the difference between the two values. The first power PW1 may also be a voltage value.

[0011] The first conductive member 21 is heated by the first power PW1. The first conductive member 21 is, for example, a heater. The heat from the first conductive member 21 causes the temperature of the first element portion 11E to rise. This causes the temperature of the first resistive element 11 to rise.

[0012] The temperature state of the first resistive element 11 depends on the state of the object to be detected around the sensor unit 10S (for example, the first element unit 11E). The object to be detected is, for example, a gas. The gas is, for example, hydrogen or carbon dioxide. The thermal conductivity characteristics (heat dissipation) change depending on the type and concentration of the gas. Due to the change in heat dissipation, the temperature state of the first resistive element 11 depends on the state of the object to be detected. By detecting the temperature of the first resistive element 11, the state of the object to be detected (such as the type and concentration of the gas) can be detected. The sensor 110 is, for example, a thermal conductivity type gas sensor.

[0013] In an embodiment, a difference between a first signal Sr1 corresponding to a first resistance of the first resistance element 11 and a second signal Sr2 is detected. As a result, a detection target can be detected with higher accuracy. The second resistance element 12 is, for example, a reference element. No.S r2 and , is detected. Thus, the detection target can be detected with higher accuracy. The second resistance element 12 is, for example, a reference element.

[0014] As described above, the first signal Sr1 changes according to a detection target around the sensor unit 10S. On the other hand, the second signal Sr2 does not change according to the detection target. The change rate of the second signal Sr2 with respect to the detection target is lower than the change rate of the first signal Sr1 with respect to the detection target.

[0015] In this example, the signal obtained from the first resistance element 11 is converted into a voltage by the first resistance voltage conversion circuit 71a (RVC). The voltage obtained by the conversion corresponds to the first signal Sr1. The signal obtained from the second resistance element 12 is converted into a voltage by the second resistance voltage conversion circuit 71b. The voltage obtained by the conversion corresponds to the second signal Sr2. These signals are input to the differential circuit 71D. A detection value Vout corresponding to the difference is output from the differential circuit 71D.

[0016] In the detection operation as described above, a reference example in which the first power PW first power PW1 is constant can be considered. In this reference example, for example, when the environmental temperature of the sensor unit 10S changes, if a constant first power PW1 is supplied to the first conductive member 21 (heater), a state in which the temperature of the first conductive member 21 is not the target temperature may occur. As a result, a case where the improvement in the accuracy of the detection result is not sufficient may occur. Made by In the above-described detection operation, a reference example in which the first power PW1 is constant can be considered. In this reference example, for example, when the environmental temperature of the sensor unit 10S changes, if a constant first power PW1 is supplied to the first conductive member 21 (heater), a state in which the temperature of the first conductive member 21 is not the target temperature may occur. As a result, a case where the improvement in the accuracy of the detection result is not sufficient may occur.

[0017] In an embodiment, the first power PW1 is controlled based on the detection result of the temperature of the sensor unit 10S. As shown in FIG. 1, in the case of the sensor 110, a second signal Sr2 corresponding to the second resistance of the second resistance element 12 is supplied to the control unit 72. The control unit 72 controls the first power PW1 based on the second signal Sr2. The second resistance of the second resistance element 12 corresponds to the ambient temperature of the sensor unit 10S. By controlling the first power PW1 using the second signal Sr2 corresponding to the second resistance of the second resistance element 12, the temperature of the first conductive member 21 can be set to a target state with high accuracy. As a result, the detection target can be detected with high accuracy. According to the embodiment, a sensor capable of improving characteristics can be provided.

[0018] As shown in FIG. 1, in this example, the control unit 72 includes a driver circuit 72D and a processing circuit 73C. The driver circuit 72D can supply the first power PW1 to the first conductive member 21. The driver circuit 72D may be able to apply a voltage corresponding to the first power PW1 to the first conductive member 21. The processing circuit 73C can control the driver circuit 72D based on the second signal Sr2 to control the first power PWl (or voltage).

[0019] For example, the driver circuit may include a circuit that generates a standard voltage. The processing circuit 73C may generate a correction voltage according to the second signal Sr2. The first power PW1 (voltage) may be controlled by adding the standard voltage and the correction voltage.

[0020] As shown in FIG. 1, in one example, the processing circuit 73C includes a processing unit 73R and a memory 73M. The memory 73M can store the relationship between the change in the second signal Sr2 and the control value regarding the first power PW1. For example, the memory 73M may be able to store a table regarding these relationships. For example, the memory 73M may be able to store a function regarding these relationships. The processing unit 73R can control the driver circuit 72D based on the above relationship stored in the memory 73M and the second signal Sr2 supplied to the control unit 72 (for example, the processing circuit 73C). For example, a control signal Sc1 is supplied from the processing unit 73R to the driver circuit 72D.

[0021] The second signal Sr2 obtained from the second resistive element 12 changes according to the second temperature around the sensor unit 10S. The second resistive element 12 functions as a temperature sensor. The first power PW1 changes according to the second temperature (e.g., ambient temperature).

[0022] The following describes an example of the sensor unit 10S. Figure 2 is a schematic cross-sectional view illustrating a sensor according to the first embodiment. Figures 3 and 4 are schematic plan views illustrating the sensor according to the first embodiment. Figure 2 is a cross-sectional view taken along the line A1-A2 in Figure 3.

[0023] As shown in Figure 2, the sensor unit 10S further includes a base body 41. The first element unit 11E and the second element unit 12E are fixed to the base body 41. By providing these element units on a single base body 41, the temperatures of these element units become substantially the same when no power is supplied to the first conductive member 21. This enables higher accuracy detection when using the second resistive element 12 as a reference.

[0024] The first power PW1 is controlled based on a second signal Sr2 corresponding to the second resistance of the second resistive element 12. The second element section 12E, which includes the second resistive element 12, is spatially close to the first element section 11E. The first power PW1 is controlled with good spatial responsiveness. In this embodiment, the heat capacity of the first element section 11E is small. The temperature of the first element section 11E can be changed in a short time. The first power PW1 can be controlled with high temporal responsiveness.

[0025] As shown in Figure 2, the substrate 41 may include a semiconductor substrate 41s and an insulating layer 41i. The semiconductor substrate 41s may be, for example, a silicon substrate. The insulating layer 41i is provided on the semiconductor substrate 41s. A portion of the semiconductor substrate 41s may include transistors and the like. At least a portion of the circuit section 70 may be formed by a portion of the semiconductor substrate 41s.

[0026] As shown in Figure 2, the sensor unit 10S includes a first holding part 31aS and a second holding part 32aS. The first holding part 31aS and the second holding part 32aS are fixed to the base body 41. The first holding part 31aS holds the first element part 11E. A first air gap g1 is provided between the base body 41 and the first element part 11E. The second holding part 32aS holds the second element part 12E. A second air gap g2 is provided between the base body 41 and the second element part 12E. By providing these air gaps, external influences, for example, through the base body 41 are suppressed. Higher accuracy is easier to obtain.

[0027] The first holding portion 31aS is included in the first detection element 10A. The second holding portion 32aS is included in the second detection element 10B. In this example, the first detection element 10A includes a first connection portion 31aC. The first connection portion 31aC connects the first element portion 11E to the first holding portion 31aS. The second detection element 10B includes a second connection portion 32aC. The second connection portion 32aC connects the second element portion 12E to the second holding portion 32aS. These connection portions may have, for example, a meander structure. These connection portions provide low thermal conductivity. For example, the first element portion 11E can be heated efficiently.

[0028] The first element portion 11E includes a first insulating member 18A. At least a portion of the first insulating member 18A is provided between the first conductive member 21 and the first resistive element 11.

[0029] In this example, the second element section 12E includes a second conductive member 22. For example, the configuration of the second element section 12E is the same as that of the first element section 11E. For example, the thermal characteristics (heat capacity, etc.) of the second element section 12E are substantially the same as those of the first element section 11E. Higher accuracy correction is possible. Power does not need to be supplied to the second conductive member 22. The second element section 12E includes a second insulating member 18B. At least a portion of the second insulating member 18B is provided between the second conductive member 22 and the second resistive element 12.

[0030] In this example, the sensor unit 10S includes a first opposing holding unit 31bS and a second opposing holding unit 32bS. The first opposing holding unit 31bS and the second opposing holding unit 32bS are fixed to the base 41. The first opposing holding unit 31bS holds the first element unit 11E. The second opposing holding unit 32bS holds the second element unit 12E. The element unit is held more stably.

[0031] In this example, the first detection element 10A includes a first opposing connection part 31bC. The first opposing connection part 31bC connects the first element part 11E to the first opposing holding part 31bS. The second detection element 10B includes a second opposing connection part 32bC. The second opposing connection part 32bC connects the second element part 12E to the second opposing holding part 32bS.

[0032] As shown in Figure 3, the first detection element 10A may include a first other-holding portion 31cS, a first other-connecting portion 31cC, a first other-opposing-holding portion 31dS, and a first other-opposing-connecting portion 31dC. The first other-holding portion 31cS and the first other-opposing-holding portion 31dS are fixed to the base body 41. The first other-connecting portion 31cC connects the first element portion 11E to the first other-holding portion 31cS. The first other-opposing-connecting portion 31dC connects the first element portion 11E to the first other-opposing-holding portion 31dS.

[0033] As shown in Figure 3, the second detection element 10B may include a second other-holding portion 32cS, a second other-connecting portion 32cC, a second other-opposing-holding portion 32dS, and a second other-opposing-connecting portion 32dC. The second other-holding portion 32cS and the second other-opposing-holding portion 32dS are fixed to the base 41. The second other-connecting portion 32cC connects the second element portion 12E to the second other-holding portion 32cS. The second other-opposing-connecting portion 32dC connects the second element portion 12E to the second other-opposing-holding portion 32dS.

[0034] In this example, the first resistive element 11 is electrically connected to the outside (e.g., the circuit section 70) via the first connection part 31aC and the first opposing connection part 31bC. The first conductive member 21 is electrically connected to the outside (e.g., the circuit section 70) via the first other connection part 31cC and the first other opposing connection part 31dC.

[0035] In this example, the second resistive element 12 is electrically connected to the outside (e.g., the circuit section 70) via the second connection part 32aC and the second opposing connection part 32bC. The second conductive member 22 does not need to be electrically connected to the outside (e.g., the circuit section 70).

[0036] Figure 4 illustrates the pattern shape of a layer including a first resistive element 11 and a second resistive element 12. As shown in Figure 4, a first film 15a and a second film 15b may be provided. The first resistive element 11 is provided between the first film 15a and the second film 15b. The material of these films may be the same as the material of the first resistive element 11. A third film 15c and a fourth film 15d may be provided. The second resistive element 12 is provided between the third film 15c and the fourth film 15d. The material of these films may be the same as the material of the second resistive element 12. These films suppress deformation of, for example, the first element portion 11E and the second element portion 12E.

[0037] Figures 5(a) to 5(e) are schematic diagrams illustrating the operation of the sensor according to the first embodiment. These figures are time charts illustrating the first operation. The horizontal axis of these figures represents time tm. The vertical axis of Figure 5(a) represents the value of the first power PW1, PW1(t). The vertical axis of Figure 5(b) represents the value of the first signal Sr1, Sr1(t). The vertical axis of Figure 5(c) represents the value of the second signal Sr2, Sr2(t). The vertical axis of Figure 5(d) represents the value of the detected value Vout, Vout(t). The vertical axis of Figure 5(e) represents the value of the control signal Sc1, Sc1(t).

[0038] As shown in Figure 5(a), for example, a pulse of first power PW1 is repeatedly output. The pulse may be output repeatedly over a first period T1. One pulse corresponds to one first operation. As shown in Figure 5(b), the first signal Sr1 fluctuates in accordance with the pulse of first power PW1. On the other hand, as shown in Figure 5(c), for example, the second signal Sr2 changes in response to a change in ambient temperature. Based on the first signal Sr1 and the second signal Sr2, a detected value Vout corresponding to the difference between these signals is calculated. The detected value Vout corresponds to, for example, the detection result of the object to be detected. The detected value Vout may be an analog value or a digital value. The detected value Vout is output over one first period T1.

[0039] As shown in Figure 5(e), a control signal Sc1 is output. The control signal Sc1 is based, for example, on a second signal Sr2. The control signal Sc1 may be an analog signal or a digital signal. The pulse following the first power PW1 is controlled based on the control signal Sc1. This operation may be repeated.

[0040] Thus, the circuit unit 70 may be capable of repeating the first operation. The repetition has a first period T1. For example, the first period T1 includes a first period Tp1 and a second period Tp2 following the first period Tp1. In this example, during the first period Tp1, the control unit 72 supplies a first power PW1 to the first conductive member 21, and the detection unit 71 outputs a detected value Vout. The control unit 72 controls the first power PW1 based on the second signal Sr2 during the second period Tp2. For example, the first period Tp1 is more powerful than the second period Tp2. long It is not necessary. A longer first period Tp1 allows for a sufficiently long time to detect the target, for example, making it easier to obtain highly accurate detection results. A shorter second period Tp2 allows for a shorter first period T1. This enables high-frequency detection operations.

[0041] Figure 6 is a schematic cross-sectional view illustrating a sensor according to the first embodiment. As shown in Figure 6, the sensor 111 according to this embodiment also includes a sensor unit 10S and a circuit unit 70 (see Figure 1). The sensor unit 10S includes a first element unit 11E and a second element unit 12E. The first element unit 11E includes a first resistive element 11 and a first conductive member 21. The second element unit 12E includes a second resistive element 12. The circuit unit 70 includes a detection unit 71 and a control unit 72 (see Figure 1).

[0042] In the sensor 111, the first element portion 11E has a MEMS structure. The second element portion 12E is fixed to the base 41, and there is no gap between the base 41 and the second element portion 12E.

[0043] In the sensor 111, the circuit unit 70 can also perform the first operation described for the sensor 110 (see Figure 1). For example, in the first operation, the control unit 72 can control the first power PW1 based on the second signal Sr2 corresponding to the second resistance of the second resistive element 12. In the first operation, the control unit 72 can supply the controlled first power PW1 to the first conductive member 21 to raise the first temperature of the first element unit 11E. In the first operation, the detection unit 71 receives the first signal Sr1 corresponding to the first resistance of the first resistive element 11 in the first state where the first temperature has risen, and the second signal No. S r2 and It is possible to output a detected value Vout corresponding to the difference between the two values. Sensor 111 can also detect the target with high accuracy. According to this embodiment, a sensor with improved characteristics can be provided.

[0044] (Second Embodiment) Figure 7 is a block diagram illustrating a sensor according to the second embodiment. As shown in Figure 7, the sensor 120 according to this embodiment includes a sensor unit 10S and a circuit unit 70. In the sensor 120, the sensor unit 10S includes a temperature sensor 13. The configuration of the sensor 120, excluding the temperature sensor 13, may be the same as that of the sensor 110.

[0045] In the sensor 120, the sensor section 10S includes a first element section 11E, a second element section 12E, and a temperature sensor 13. The first element section 11E includes a first resistive element 11 and a first conductive member 21. The second element section 12E includes a second resistive element 12. The second element section 12E may include a second conductive member 22.

[0046] In the sensor 120, the circuit section 70 includes a detection section 71 and a control section 72. The circuit section 70 is capable of performing a first operation. In the first operation, the control section 72 can control a first power PW1 based on the detection signal Sr3 of the temperature sensor 13. In the first operation, the control section 72 can supply the controlled first power PW1 to the first conductive member 21 to raise the first temperature of the first element section 11E. In the first operation, the detection section 71 can output a detected value Vout corresponding to the difference between a first signal Sr1 corresponding to the first resistance of the first resistive element 11 in the first state where the first temperature has risen, and a second signal Sr2 corresponding to the second resistance of the second resistive element 12.

[0047] In sensor 120, the first power PW1 is controlled using the detection signal Sr3 from temperature sensor 13. This allows the temperature of the first conductive member 21 to be brought to the desired state with high precision. As a result, the target object can be detected with high precision. According to this embodiment, a sensor capable of improving characteristics can be provided.

[0048] The control unit 72 may include a driver circuit 72D and a processing circuit 73C. The driver circuit 72D is capable of supplying a first power PW1 to the first conductive member 21. The processing circuit 73C is capable of controlling the first power PW1 by controlling the driver circuit 72D based on a detection signal Sr3. For example, a control signal Sc1 is supplied from the processing unit 73R to the driver circuit 72D.

[0049] For example, the processing circuit 73C may include a processing unit 73R and a memory 73M. The memory 73M can store the relationship between the change in the detection signal Sr3 and a control value related to the first power PW1. The processing unit 73R can control the driver circuit 72D based on the above relationship stored in the memory 73M and the detection signal Sr3 supplied to the control unit 72 (for example, the processing circuit 73C).

[0050] In the sensor 120, the detection signal Sr3 changes according to the second temperature around the sensor unit 10S. For example, the first power PW1 changes according to the second temperature.

[0051] For example, the first signal Sr1 corresponding to the first resistive element 11 changes according to the object to be detected around the sensor unit 10S (e.g., the state of the target gas). The second signal Sr2 does not change according to the object to be detected. Or, the rate of change of the second signal Sr2 with respect to the object to be detected is lower than the rate of change of the first signal Sr1 with respect to the object to be detected.

[0052] Figure 8 is a schematic cross-sectional view illustrating a sensor according to the second embodiment. As shown in Figure 8, in the sensor 120, the sensor unit 10S further includes a base 41. The first element unit 11E, the second element unit 12E, and the temperature sensor 13 are fixed to the base 41. This enables control with high spatial responsiveness. Any element can be used as the temperature sensor 13.

[0053] For example, the sensor unit 10S includes a first holding part 31aS fixed to the base body 41 and a second holding part 32aS fixed to the base body 41. The first holding part 31aS holds the first element part 11E. A first air gap g1 is provided between the base body 41 and the first element part 11E. The second holding part 32aS holds the second element part 12E. A second air gap g2 is provided between the base body 41 and the second element part 12E. The first conductive member 21 can be heated efficiently. External thermal influences via the base body 41 and the like can be suppressed. Higher accuracy detection becomes possible.

[0054] The embodiment may include the following configuration (technical proposal). (Composition 1) A sensor unit, the sensor unit comprising a first element unit including a first resistive element and a first conductive member, and a second element unit including a second resistive element, A circuit section including a detection unit and a control unit, Equipped with, The circuit section is capable of performing the first operation, The control unit is capable of controlling the first power in the first operation based on a second signal corresponding to the second resistance of the second resistive element. The control unit is capable of supplying the first power to the first conductive member in the first operation to raise the first temperature of the first element, The detection unit is a sensor capable of outputting a detection value corresponding to the difference between a first signal corresponding to the first resistance of the first resistive element in the first state where the first temperature has risen, and the second signal, during the first operation. (Configuration 2) The sensor part further includes a substrate, The sensor according to configuration 1, wherein the first element and the second resistive element are fixed to the substrate. (Composition 3) The aforementioned sensor unit is A first retaining part fixed to the base, A second holding portion fixed to the base, It further includes, The first holding portion holds the first element portion, A first gap is provided between the substrate and the first element portion. The second holding portion holds the second element portion, The sensor according to configuration 2, wherein a second gap is provided between the substrate and the second element portion. (Composition 4) The control unit includes a driver circuit and a processing circuit. The driver circuit is capable of supplying the first power to the first conductive member. The sensor according to any one of configurations 1 to 3, wherein the processing circuit controls the driver circuit based on the second signal to control the first power. (Composition 5) The processing circuit includes a processing unit and a memory, The memory is capable of storing the relationship between the change in the second signal and the control value for the first power. The sensor according to configuration 4, wherein the processing unit can control the driver circuit based on the relationship stored in the memory and the second signal supplied to the control unit. (Composition 6) The second signal changes according to the second temperature around the sensor unit. The first power is a sensor according to any one of configurations 1 to 5, wherein the first power changes according to the second temperature. (Composition 7) The first signal changes according to the object being detected around the sensor unit. The sensor according to any one of configurations 1 to 6, wherein the second signal does not change according to the object to be detected, or the rate of change of the second signal with respect to the object to be detected is lower than the rate of change of the first signal with respect to the object to be detected. (Composition 8) The circuit section is capable of repeating the first operation. The aforementioned repetition has a first period, The aforementioned first period includes a first period and a second period following the aforementioned first period. During the first period, the control unit supplies the first power to the first conductive member, and the detection unit outputs the detected value. The control unit controls the first power based on the second signal during the second period. The first period is longer than the second period. long i. A sensor listed in any one of configurations 1 to 7. (Composition 9) A sensor unit, the sensor unit includes a first element unit including a first resistive element and a first conductive member, a second element unit including a second resistive element, a temperature sensor, and the sensor unit. A circuit section including a detection unit and a control unit, Equipped with, The circuit section is capable of performing the first operation, The control unit is capable of controlling the first power based on the detection signal from the temperature sensor during the first operation. The control unit is capable of supplying the first power to the first conductive member in the first operation to raise the first temperature of the first element, The detection unit is a sensor capable of outputting a detected value corresponding to the difference between a first signal corresponding to the first resistance of the first resistive element in the first state in which the first temperature has risen, and a second signal corresponding to the second resistance of the second resistive element in the first operation. (Composition 10) The sensor part further includes a substrate, The first element section, the second element section, and the temperature sensor are fixed to the base body, as described in configuration 9. (Composition 11) The aforementioned sensor unit is A first retaining part fixed to the base, A second holding portion fixed to the base, It further includes, The first holding portion holds the first element portion, A first gap is provided between the substrate and the first element portion. The second holding portion holds the second element portion, The sensor according to configuration 10, wherein a second gap is provided between the substrate and the second element portion. (Composition 12) The control unit includes a driver circuit and a processing circuit. The driver circuit is capable of supplying the first power to the first conductive member. The sensor according to any one of configurations 9 to 11, wherein the processing circuit controls the driver circuit based on the detection signal to control the first power. (Composition 13) The processing circuit includes a processing unit and a memory, The memory is capable of storing the relationship between the change in the detection signal and the control value for the first power. The sensor according to configuration 12, wherein the processing unit can control the driver circuit based on the relationship stored in the memory and the detection signal supplied to the control unit. (Composition 14) The detection signal changes according to the second temperature around the sensor unit. The first power is varied according to the second temperature, as described in any one of configurations 9 to 13 of the sensor. (Composition 15) The first signal changes according to the object being detected around the sensor unit. The sensor according to any one of configurations 9 to 14, wherein the second signal does not change according to the object to be detected, or the rate of change of the second signal with respect to the object to be detected is lower than the rate of change of the first signal with respect to the object to be detected.

[0055] According to the embodiment, a sensor capable of improving its characteristics can be provided.

[0056] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configuration of each element included in the sensor, such as the substrate, sensor unit, and control unit, is included within the scope of the present invention as long as those skilled in the art can appropriately select from the known range to implement the present invention in the same way and obtain the same effects.

[0057] Furthermore, combinations of two or more elements from any of the specific examples, to the extent technically feasible, are also included within the scope of the present invention, insofar as they encompass the gist of the invention.

[0058] Furthermore, all sensors that a person skilled in the art can implement by appropriately modifying the design based on the sensors described above as embodiments of the present invention also fall within the scope of the present invention, insofar as they encompass the gist of the present invention.

[0059] Furthermore, within the scope of the concept of the present invention, a person skilled in the art could conceive of various modifications and alterations, and it is understood that such modifications and alterations also fall within the scope of the present invention.

[0060] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of symbols]

[0061] 10A, 10B: First and second detection elements, 10S: Sensor section, 11, 12: First and second resistive elements, 11E, 12E: First and second element sections, 13: Temperature sensor, 15a~15d: First to fourth films, 18A, 18B: First and second insulating members, 21, 22: First and second conductive members, 31aC, 32aC: First and second connection sections, 31aS, 32aS: First and second holding sections, 31bC, 32bC: First and second opposing connection sections, 31bS, 32bS: First and second opposing holding sections, 31cC, 32cC: First and second other connection sections, 31cS, 32cS: First and second other holding sections 31dC, 32dC: First and second opposing connection parts, 31dS, 32dS: First and second opposing holding parts, 41: Substrate, 41i: Insulating layer, 41s: Semiconductor substrate, 70: Circuit section, 71: Detection section, 71D: Differential circuit, 71a, 71b: First and second resistance-voltage conversion circuits, 72: Control section, 72D: Driver circuit, 73C: Processing circuit, 73M: Memory, 73R: Processing section, 110, 111, 120: Sensors, PW1: First power, Sc1: Control signal, Sr1, Sr2: First and second signals, Sr3: Detection signal, T1: Period, Vout: Detected value, g1, g2: First and second gaps

Claims

1. A sensor unit, the sensor unit comprising a first element unit including a first resistive element and a first conductive member, and a second element unit including a second resistive element, A circuit section including a detection unit and a control unit, Equipped with, The circuit section is capable of performing the first operation, The control unit is capable of controlling the first power in the first operation based on a second signal corresponding to the second resistance of the second resistive element. The control unit is capable of supplying the first power to the first conductive member in the first operation to raise the first temperature of the first element. The detection unit is capable of outputting a detection value corresponding to the difference between a first signal corresponding to the first resistance of the first resistive element in the first state where the first temperature has risen, and the second signal during the first operation. The control unit includes a driver circuit and a processing circuit. The driver circuit is capable of supplying the first power to the first conductive member. The processing circuit can control the driver circuit based on the second signal to control the first power. The processing circuit includes a processing unit and a memory, The memory is capable of storing the relationship between the change in the second signal and the control value related to the first power. The processing unit is capable of controlling the driver circuit based on the relationship stored in the memory and the second signal supplied to the control unit.

2. The sensor part further includes a substrate, The sensor according to claim 1, wherein the first element portion and the second resistive element are fixed to the substrate.

3. The aforementioned sensor unit is A first holding portion fixed to the base, A second holding portion fixed to the base, It further includes, The first holding portion holds the first element portion, A first gap is provided between the substrate and the first element portion. The second holding portion holds the second element portion, The sensor according to claim 2, wherein a second gap is provided between the substrate and the second element portion.

4. The second signal changes according to the second temperature around the sensor unit. The sensor according to claim 1, wherein the first power changes according to the second temperature.

5. A sensor unit, the sensor unit comprising a first element unit including a first resistive element and a first conductive member, and a second element unit including a second resistive element, A circuit section including a detection unit and a control unit, Equipped with, The circuit section is capable of performing the first operation, The control unit is capable of controlling the first power in the first operation based on a second signal corresponding to the second resistance of the second resistive element. The control unit is capable of supplying the first power to the first conductive member in the first operation to raise the first temperature of the first element. The detection unit is capable of outputting a detection value corresponding to the difference between a first signal corresponding to the first resistance of the first resistive element in the first state where the first temperature has risen, and the second signal during the first operation. The first signal changes according to the object being detected around the sensor unit. A sensor in which the second signal does not change according to the detected object, or the rate of change of the second signal with respect to the detected object is lower than the rate of change of the first signal with respect to the detected object.

6. A sensor unit, wherein the sensor unit includes a first element unit including a first resistive element and a first conductive member, and a second element unit including a second resistive element, A circuit section including a detection unit and a control unit, Equipped with, The circuit section is capable of performing the first operation, The control unit is capable of controlling the first power in the first operation based on a second signal corresponding to the second resistance of the second resistive element. The control unit is capable of supplying the first power to the first conductive member in the first operation to raise the first temperature of the first element. The detection unit is capable of outputting a detection value corresponding to the difference between a first signal corresponding to the first resistance of the first resistive element in the first state where the first temperature has risen, and the second signal during the first operation. The circuit section is capable of repeating the first operation. The aforementioned repetition has a first period, The first period includes a first period and a second period following the first period. During the first period, the control unit supplies the first power to the first conductive member, and the detection unit outputs the detected value. The control unit controls the first power based on the second signal during the second period. The first period is longer than the second period.

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