Sensors

Abstract

To provide a sensor that can improve accuracy.SOLUTION: According to an embodiment, a sensor includes a first element including a first resistive member and a first conductive member, a second element including a second resistive member, and a third resistor member connected in series with the second resistive member. The absolute value of a third temperature coefficient of a third resistance of the third resistance member is smaller than the absolute value of a first temperature coefficient of a first resistance of the first resistance member. The absolute value of the third temperature coefficient is smaller than the absolute value of a second temperature coefficient of a second resistance of the second resistance member. The third resistance is lower than the second resistance.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE The present invention relates to a sensor. [Background technology]

[0002] For example, there are sensors using MEMS (Micro Electro Mechanical Systems) elements, etc. In sensors, improvement in accuracy is desired. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-41893 A Summary of the Invention [Problem to be solved by the invention]

[0004] The embodiments provide a sensor that allows for improved accuracy. [Means for solving the problem]

[0005] According to an embodiment, the sensor includes a first element including a first resistive member and a first conductive member, a second element including a second resistive member, and a third resistive member connected in series with the second resistive member. An absolute value of a third temperature coefficient of a third resistance of the third resistive member is smaller than an absolute value of a first temperature coefficient of a first resistance of the first resistive member. The absolute value of the third temperature coefficient is smaller than an absolute value of a second temperature coefficient of a second resistance of the second resistive member. The third resistance is lower than the second resistance. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic view illustrating the sensor according to the first embodiment. [Diagram 2] FIG. 2 is a graph illustrating characteristics related to the sensor. [Diagram 3]FIG. 3 is a schematic cross-sectional view illustrating the sensor according to the first embodiment. [Figure 4] 4A and 4B are schematic cross-sectional views illustrating the sensor according to the first embodiment. [Diagram 5] FIG. 5 is a schematic plan view illustrating the sensor according to the first embodiment. [Figure 6] 6A and 6B are schematic plan views illustrating the sensor according to the first embodiment. [Figure 7] FIG. 7 is a schematic view illustrating the sensor according to the second embodiment. [Figure 8] FIG. 8 is a schematic plan view illustrating the sensor according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios of each part may be different depending on the drawing. In this specification and each drawing, elements similar to those described above with reference to the previous drawings are given the same reference numerals and detailed descriptions thereof will be omitted as appropriate.

[0008] (First embodiment) FIG. 1 is a schematic view illustrating the sensor according to the first embodiment. Fig. 1 is a circuit diagram of a sensor 110 according to an embodiment. As shown in Fig. 1, the sensor 110 includes a first element 10A and a second element 10B.

[0009] The first element 10A includes a first resistance member 11 and a first conductive member 21. As described below, the first conductive member 21 functions as a heater. The second element 10B includes a second resistance member 12. In this example, the second element 10B includes a second conductive member 22. The second conductive member 22 is, for example, a dummy heater.

[0010] The sensor 110 further includes a third resistance member 63. The third resistance member 63 is connected in series with the second resistance member 12. The sensor 110 may include a wiring member 64 and a wiring member 65. The wiring member 64 is electrically connected to the second resistance member 12 and the third resistance member 63. The wiring member 65 is electrically connected to the first resistance member 11.

[0011] The first resistance member 11 has a first resistance R1. The second resistance member 12 has a second resistance R2. The third resistance member 63 has a third resistance R3. The wiring member 64 has a wiring resistance R4. The wiring member 65 has a wiring resistance R5. These resistances are electric resistances.

[0012] In the embodiment, the absolute value of the third temperature coefficient of the third resistance R3 of the third resistance member 63 is smaller than the absolute value of the first temperature coefficient of the first resistance R1 of the first resistance member 11. The absolute value of the third temperature coefficient is smaller than the absolute value of the second temperature coefficient of the second resistance R2 of the second resistance member 12. The third resistance member 63 is a low temperature coefficient resistor.

[0013] The third resistance R3 of the third resistance member 63 is lower than the second resistance R2 of the second resistance member 12. For example, the wiring resistance R4 of the wiring member 64 is lower than the third resistance R3.

[0014] In the embodiment, for example, a current i1 is supplied to the first conductive member 21. For example, a voltage is applied to the first conductive member 21 by the power source 76. This causes the current i1 to flow through the first conductive member 21. As the temperature of the first conductive member 21 increases, the temperature of the first resistive member 11 increases. At this time, the degree of heat conduction from the first resistive member 11 to the surrounding atmosphere changes depending on the type and concentration of the gas to be detected that is present around the first element 10A. For example, the thermal conductivity of the surrounding atmosphere changes depending on the type of gas. For example, the thermal conductivity of the surrounding atmosphere changes depending on the concentration of the gas.

[0015] The degree of heating of the first resistance member 11 changes depending on the degree of thermal conduction of the first resistance member 11. That is, the temperature of the first resistance member 11 changes depending on the type and concentration of the gas to be detected. This causes the electrical resistance of the first resistance member 11 to change. By detecting the change in the electrical resistance of the first resistance member 11, the type and concentration of the gas to be detected that is present around the first element 10A can be detected.

[0016] In this example, a first detection current id1 is supplied from a first current source 75a to the first resistance member 11. The potential of one end of the first resistance member 11 based on the first detection current id1 is detected.

[0017] On the other hand, in the second element 10B, no conductive member is provided. Or, even if a conductive member (second conductive member 22) is provided in the second element 10B, no current is supplied to the second conductive member 22. As a result, the temperature of the second resistance member 12 is not substantially affected by the detection target. By observing the difference between the characteristics of the second resistance member 12 and the characteristics of the first resistance member 11, the change in temperature of the first resistance member 11 can be detected with high accuracy. As a result, the gas to be detected can be detected with high accuracy. The second resistance member 12 is, for example, a reference element.

[0018] For example, in the second element 10B, a second detection current id2 is supplied from a second current source 75b to the second resistance member 12. The potential of the second resistance member 12 based on the second detection current id2 is detected.

[0019] In this example, a differential amplifier 71 is provided. The differential amplifier 71 includes a first input 71a and a second input 71b. A signal corresponding to the potential of the first resistance member 11 is input to the first input 71a. A signal corresponding to the potential of the second resistance member 12 is input to the second input 71b.

[0020] By detecting the difference between the potential of the first resistance member 11 and the potential of the second resistance member 12, a change in the electrical resistance of the first resistance member 11 caused by the detection target can be extracted with high accuracy.

[0021] The output of the differential amplifier 71 may be input to an AD conversion circuit 72. The change in the electrical resistance of the first resistance member 11 may be output as a digital value.

[0022] The sensor 110 may include a circuit section 70. The circuit section 70 includes a differential amplifier 71. The circuit section 70 may include an AD conversion circuit 72. The circuit section 70 may include a power supply 76. The circuit section 70 may include a first current source 75a and a second current source 75b. The value of the second detection current id2 may be the same as the value of the first detection current id1.

[0023] For example, the configuration (material and shape) of the second resistive member 12 is substantially the same as the configuration (material and shape) of the first resistive member 11. As a result, when the temperatures of these resistive members are the same, the electrical resistance and temperature coefficients of these resistive members are substantially the same. As a result, it is expected that the change in resistance of the first resistive member 11 can be detected with high accuracy by differential amplification even when the environmental temperature around the sensor changes.

[0024] However, as described above, the first resistive member 11 is heated by the first conductive member 21. Therefore, in the detection operation, the temperature of the first resistive member 11 becomes higher than the temperature of the second resistive member 12. This causes a difference (offset) between the electrical resistance of the first resistive member 11 and the electrical resistance of the second resistive member 12. This offset may cause the detection of the change in the resistance of the first resistive member 11 to be inaccurate. If the offset exceeds the operating range of the differential amplifier 71, it becomes difficult to detect the change in the resistance of the first resistive member 11.

[0025] On the other hand, a reference example is conceivable in which the second resistance member 12 is designed in advance taking into consideration the change in electrical resistance accompanying the temperature rise of the first resistance member 11. For example, the shape of the second resistance member 12 is made different from the shape of the first resistance member 11. This makes it possible to make the electrical resistance of the second resistance member 12, whose temperature does not substantially rise, substantially the same as the electrical resistance of the first resistance member 11, whose temperature has risen. However, in this reference example, since the shape of the second resistance member 12 is different from the shape of the first resistance member 11, the temperature coefficients of the electrical resistances of these resistance members do not match. There is a difference in the temperature coefficients. For this reason, for example, when the environmental temperature around the sensor changes, it is difficult to detect the change in the electrical resistance of the first resistance member 11 with high accuracy.

[0026] In the embodiment, a third resistance member 63 is provided. The third resistance member 63 is connected in series to the second resistance member 12. This increases the electrical resistance of a series circuit of the second resistance member 12 and the third resistance member 63. The electrical resistance of the series circuit can be made substantially the same as the electrical resistance of the first resistance member 11 when the temperature rises.

[0027] Furthermore, the third resistance member 63 is set to have a small temperature coefficient of electrical resistance. For example, as described below, the material of the third resistance member 63 is different from that of the first resistance member 11 and the second resistance member 12. This allows the third resistance member 63 to have a low temperature coefficient.

[0028] Since the temperature coefficient of the third resistance member 63 is small, the temperature change of the electrical resistance of the third resistance member 63 can be substantially ignored. This makes it possible to reduce the difference in temperature coefficient between the first resistance member 11 and the series circuit including the second resistance member 12 and the third resistance member 63 to a negligible level. The difference in temperature coefficient can be suppressed.

[0029] In the embodiment, for example, even when the environmental temperature around the sensor changes, the change in the electrical resistance of the first resistance member 11 can be detected with high accuracy. This allows the detection target to be detected with high accuracy over a wide temperature range.

[0030] For example, the first resistance member 11 is heated by the first conductive member 21. The first resistance member 11 is made of a material that provides stable characteristics even when heated. Materials that prioritize stability of characteristics do not necessarily have a small temperature coefficient. In other words, the temperature coefficient of the first resistance member 11 is relatively large.

[0031] As already described, the second resistance member 12 is a reference element. For this reason, it is preferable that the configuration of the second resistance member 12 is set to be substantially the same as the configuration of the first resistance member 11. Therefore, like the first resistance member 11, the temperature characteristic of the second resistance member 12 is also large.

[0032] In the embodiment, by providing the third resistance member 63, the configuration of the second resistance member 12 can be made the same as the configuration of the first resistance member 11. This allows, for example, the temperature coefficient of the second resistance member 12 to be substantially the same as the temperature coefficient of the first resistance member 11. For example, the design of the second resistance member 12 becomes simple, and the manufacturing efficiency is also high.

[0033] As described above, in the embodiment, the absolute value of the third temperature coefficient of the third resistance R3 of the third resistance member 63 is smaller than the absolute value of the first temperature coefficient of the first resistance R1 of the first resistance member 11. The absolute value of the third temperature coefficient is smaller than the absolute value of the second temperature coefficient of the second resistance R2 of the second resistance member 12. The third resistance member 63 having a small temperature coefficient is used. This allows the electrical resistance of the series circuit including the second element 10B and the third resistance member 63 to be substantially the same as the resistance of the first element 10A when heated. And, the temperature coefficient of the series circuit can be substantially the same as the temperature coefficient of the first element 10A.

[0034] In the embodiment, the third resistance R3 is lower than the second resistance R2. The sum of the third resistance R3 and the second resistance R2 is substantially the same as the first resistance R1 when heated. For example, the third resistance R3 corresponds to the difference between the first resistance R1 when heated and the second resistance R2 when not substantially heated. The change in the first resistance R1 due to the temperature change of the first resistance member 11 is smaller than the absolute value of the first resistance R1 (i.e., the absolute value of the second resistance R2). Since the third resistance R3 is lower than the second resistance R2, the sum of the third resistance R3 and the second resistance R2 can be substantially the same as the first resistance R1 when heated. In the embodiment, the third resistance R3 is lower than the first resistance R1.

[0035] Wiring resistance exists in the first element 10A and the second element 10B. The wiring resistance is lower than the resistance of the resistive member. This makes it possible to suppress loss and obtain the intended operation.

[0036] For example, in the first element 10A, there is a wiring resistance (not shown in FIG. 1) due to a wiring member. This wiring resistance is low compared to the first resistance R1 of the first resistance member 11, and can be ignored.

[0037] For example, in the second element 10B, there is a wiring resistance R4 due to the wiring member 64. This wiring resistance R4 is lower than the second resistance R2 of the second resistance member 12 and lower than the third resistance R3 of the third resistance member 63.

[0038] In the embodiment, the absolute value of the third temperature coefficient of the third resistance R3 of the third resistance member 63 is ⅓ or less of the absolute value of the first temperature coefficient of the first resistance R1 of the first resistance member. The absolute value of the third temperature coefficient is ⅓ or less of the absolute value of the second temperature coefficient of the second resistance R2 of the second resistance member 12. This makes it possible to suppress the difference in temperature coefficients.

[0039] In an embodiment, the absolute value of the first temperature coefficient is, for example, 300 ppm / K or more. The absolute value of the second temperature coefficient is, for example, 300 ppm / K or more. The absolute value of the third temperature coefficient is, for example, 100 ppm / K or less. The absolute value of the third temperature coefficient may be, for example, 50 ppm / K or less. The difference between the temperature coefficients can be further suppressed.

[0040] For example, the third resistance member 63 contains at least one selected from the group consisting of Ni and Cr. A small temperature coefficient can be obtained. For example, the third resistance member 63 contains Ni and Cr. In this case, the composition ratio of Cr in the third resistance member 63 is, for example, 30 wt% or more and 80 wt% or less. An example of the temperature coefficient of a material containing Ni and Cr will be described later.

[0041] The first resistance member 11 and the second resistance member 12 include at least one selected from the group consisting of Ti, TiN, Al, W, Si, Cu, Au, Pd, and Pt. For example, the first resistance member 11 provides stable characteristics when heated. The material of the second resistance member 12 is, for example, the same as the material of the first resistance member 11. The second resistance member 12 provides good characteristics as a reference element.

[0042] The wiring member 64 includes at least one selected from the group consisting of aluminum, copper, and gold, for example. A low wiring resistance R4 can be easily and stably obtained.

[0043] The wiring resistance R4 is, for example, 1 / 3 or less than the third resistance R3. The wiring resistance R4 is, for example, 0.01 Ω or more and less than 100 Ω. The wiring resistance R5 is, for example, 1 / 3 or less than the first resistance R1. The wiring resistance R5 is, for example, 0.01 Ω or more and less than 100 Ω. The third resistance R3 is, for example, 2 Ω or more and 100 kΩ or less. The first resistance R1 is, for example, 100 Ω or more and 1 MΩ or less. The second resistance R2 is, for example, 100 Ω or more and 1 MΩ or less.

[0044] FIG. 2 is a graph illustrating characteristics related to the sensor. FIG. 2 illustrates the temperature coefficient of a material containing Ni and Cr. The horizontal axis is the concentration C1(Cr) of Cr. The vertical axis is the temperature coefficient TCR of electrical resistivity. As shown in FIG. 2, when the concentration C1(Cr) of Cr is 30 wt% or more and 80 wt% or less, a small temperature coefficient TCR is obtained. When the third resistance member 63 contains Ni and Cr, the composition ratio of Cr in the third resistance member 63 is preferably, for example, 30 wt% or more and 80 wt% or less. When the third resistance member 63 contains Ni and Cr, the composition ratio of Cr in the third resistance member 63 is more preferably, for example, 40 wt% or more and 80 wt% or less. An even smaller temperature coefficient TCR is obtained.

[0045] An example of the configuration of the first element 10A and the second element 10B will be described below. 3, 4(a), and 4(b) are schematic cross-sectional views illustrating the sensor according to the first embodiment. FIG. 5 is a schematic plan view illustrating the sensor according to the first embodiment. Fig. 3 is a cross-sectional view taken along the line A1-A2 in Fig. 5. Fig. 4(a) is a cross-sectional view taken along the line B1-B2 in Fig. 5. Fig. 4(b) is a cross-sectional view taken along the line C1-C2 in Fig. 5.

[0046] As shown in FIGS. 3, 4(a), 4(b) and 5, a sensor 110 according to the embodiment includes a base 41, a first element 10A, a second element 10B, a third resistor member 63 and a wiring member 64.

[0047] The base 41 includes a first base region 41a and a second base region 41b. In this example, the base 41 includes a substrate 41s and an insulating film 41i. The substrate 41s may be, for example, a semiconductor substrate (e.g., a silicon substrate). The substrate 41s may include, for example, a semiconductor circuit. The substrate 41s may include a connection member such as a via electrode.

[0048] The first element 10A is provided in the first base region 41a. A first direction from the first base region 41a to the first element 10A is defined as the Z-axis direction. A direction perpendicular to the Z-axis direction is defined as the X-axis direction. A direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction.

[0049] A second direction from the first substrate region 41a to the second substrate region 41b intersects with the first direction. The second direction is, for example, the X-axis direction.

[0050] The first element 10A includes a first detection element 11E. The first detection element 11E includes a first resistance member 11 and a first conductive member 21. As shown in FIG. 3 and FIG. 5, the first resistance member 11 includes a first resistance portion 11a and a first other resistance portion 11b. For example, the first resistance portion 11a may be one end of the first resistance member 11. The first other resistance portion 11b may be another end of the first resistance member 11. As shown in FIG. 4(a) and FIG. 5, the first conductive member 21 includes a first conductive portion 21a and a first other conductive portion 21b. For example, the first conductive portion 21a may be one end of the first conductive member 21. The first other conductive portion 21b may be another end of the first conductive member 21.

[0051] 3 and 5, in this example, the first element 10A further includes a first connection portion 31C and a first support portion 31S. The first support portion 31S is fixed to the base 41. A portion of the first connection portion 31C is supported by the first support portion 31S. Another portion of the first connection portion 31C supports the first detection element 11E away from the first base region 41a. A first gap g1 is provided between the first base region 41a and the first detection element 11E.

[0052] In this example, the first element 10A further includes a first other connection portion 31aC and a first other support portion 31aS. The first other support portion 31aS is fixed to the base 41. A portion of the first other connection portion 31aC is supported by the first other support portion 31aS. Another portion of the first other connection portion 31aC supports the first detection element 11E away from the first base region 41a. In this example, at least a portion of the first detection element 11E is between the first connection portion 31C and the first other connection portion 31aC.

[0053] Second element 10B is provided in second base region 41b. The direction from second base region 41b to second element 10B is along the Z-axis direction.

[0054] The second element 10B includes a second detection element 12E. In this example, the second detection element 12E includes a second resistive member 12 and a second conductive member 22. As shown in FIG. 3 and FIG. 5, the second resistive member 12 includes a second resistive portion 12a and a second resistive other portion 12b. For example, the second resistive portion 12a may be one end of the second resistive member 12. The second resistive other portion 12b may be another end of the second resistive member 12. As shown in FIG. 4(b) and FIG. 5, the second conductive member 22 includes a second conductive portion 22a and a second conductive other portion 22b. For example, the second conductive portion 22a may be one end of the second conductive member 22. The second conductive other portion 22b may be another end of the second conductive member 22.

[0055] 3 and 5, in this example, the second element 10B further includes a second connection portion 32C and a second support portion 32S. The second support portion 32S is fixed to the base 41. A portion of the second connection portion 32C is supported by the second support portion 32S. Another portion of the second connection portion 32C supports the second detection element 12E away from the second base region 41b. In this example, a second gap g2 is provided between the second base region 41b and the second detection element 12E.

[0056] In this example, the second element 10B further includes a second other connection portion 32aC and a second other support portion 32aS. The second other support portion 32aS is fixed to the base 41. A portion of the second other connection portion 32aC is supported by the second other support portion 32aS. Another portion of the second other connection portion 32aC supports the second detection element 12E away from the second base region 41b. In this example, at least a portion of the second detection element 12E is between the second connection portion 32C and the second other connection portion 32aC.

[0057] The first detection elements 11E are supported at a distance from the base 41, thereby preventing the heat of these detection elements from being conducted via the base 41. This facilitates stable detection of the detection target with high sensitivity.

[0058] For example, the first resistance portion 11a is electrically connected to the circuit portion 70 via the wiring layer 51M and the terminal 51MT. For example, the first resistance other portion 11b is electrically connected to the circuit portion via the wiring layer 51aM and the terminal 51aMT. For example, the first conductive portion 21a is electrically connected to the circuit portion 70 via the wiring layer 53M and the terminal 53MT. For example, the first conductive other portion 21b is electrically connected to the circuit portion via the wiring layer 53aM and the terminal 53aMT.

[0059] For example, the second resistance portion 12a is electrically connected to the third resistance member 63 via the wiring layer 52M. The third resistance member 63 is electrically connected to the wiring member 64. The wiring member 64 is electrically connected to the circuit portion 70 via the terminal 52MT. For example, the second resistance other portion 12b is electrically connected to the circuit portion via the wiring layer 52aM and the terminal 52aMT. The second conductive portion 22a is not electrically connected to the circuit portion 70. The second conductive other portion 22b is not electrically connected to the circuit portion. In the embodiment, the second conductive portion 22a and the second conductive other portion 22b may be electrically connected to the circuit portion 70, and a current may not be supplied from the circuit portion 70.

[0060] The circuit section 70 outputs a signal 70s according to the output of a differential amplifier 71 (see FIG. 1).

[0061] As shown in FIG. 3, the first element 10A (and the first detection element 11E) may include a first insulating member 18A. The second element 10B (and the second detection element 12E) may include a second insulating member 18B. At least a portion of the first insulating member 18A is provided around the first resistance member 11 and the first conductive member 21. A portion of the first insulating member 18A is provided between the first resistance member 11 and the first conductive member 21. At least a portion of the second insulating member 18B is provided around the second resistance member 12 and the second conductive member 22. A portion of the second insulating member 18B is provided between the second resistance member 12 and the second conductive member 22. The second insulating member 18B has substantially the same structure as the first insulating member 18A. The length, width, thickness, and material of the second insulating member 18B are substantially the same as the length, width, thickness, and material of the first insulating member 18A.

[0062] 3, the first element 10A may further include a first conductive layer 51L. The first conductive layer 51L is electrically connected to the first resistance portion 11a of the first resistance member 11. At least a portion of the first conductive layer 51L may be provided on the first support portion 31S. In this example, the first conductive layer 51L is electrically connected to a wiring layer 51M provided on the base 41.

[0063] 3, the second element 10B may further include a second conductive layer 52L. The second conductive layer 52L is electrically connected to the second resistance portion 12a of the second resistance member 12. At least a portion of the second conductive layer 52L may be provided on the second support portion 32S. In this example, the second conductive layer 52L is electrically connected to a wiring layer 52M provided on the base 41.

[0064] The first element 10A may further include a first other conductive layer 51aL. The first other conductive layer 51aL is electrically connected to the first resistor other portion 11b of the first resistor member 11. At least a portion of the first other conductive layer 51aL may be provided on the first other support portion 31aS. In this example, the first other conductive layer 51aL is electrically connected to a wiring layer 51aM provided on the base 41. The second element 10B may further include a second other conductive layer 52aL. The second other conductive layer 52aL is electrically connected to the second resistor other portion 12b of the second resistor member 12. At least a portion of the second other conductive layer 52aL may be provided on the second other support portion 32aS. In this example, the second other conductive layer 52aL is electrically connected to a wiring layer 52aM provided on the base 41.

[0065] 4(a) and 5, in this example, the first element 10A includes a third connection portion 33C and a third support portion 33S. The third support portion 33S is fixed to the base 41. A portion of the third connection portion 33C is supported by the third support portion 33S. Another portion of the third connection portion 33C supports the first detection element 11E away from the first base region 41a.

[0066] In this example, the first element 10A includes a third other connection portion 33aC and a third other support portion 33aS. The third other support portion 33aS is fixed to the base 41. A portion of the third other connection portion 33aC is supported by the third other support portion 33aS. Another portion of the third other connection portion 33aC supports the first detection element 11E away from the first base region 41a.

[0067] 4(a), the first element 10A may further include a third conductive layer 53L. At least a portion of the third conductive layer 53L is provided on the third support portion 33S. In this example, the third conductive layer 53L is electrically connected to a wiring layer 53M provided on the base 41.

[0068] 4(a), the first element 10A may further include a third other conductive layer 53aL. At least a portion of the third other conductive layer 53aL is provided on the third other support portion 33aS. In this example, the third other conductive layer 53aL is electrically connected to a wiring layer 53aM provided on the base 41.

[0069] 4(b) and 5, in this example, the second element 10B includes a fourth connection portion 34C and a fourth support portion 34S. The fourth support portion 34S is fixed to the base 41. A portion of the fourth connection portion 34C is supported by the fourth support portion 34S. Another portion of the fourth connection portion 34C supports the second detection element 12E away from the second base region 41b.

[0070] In this example, the second element 10B includes a fourth other connection portion 34aC and a fourth other support portion 34aS. The fourth other support portion 34aS is fixed to the base 41. A portion of the fourth other connection portion 34aC is supported by the fourth other support portion 34aS. Another portion of the fourth other connection portion 34aC supports the second detection element 12E away from the second base region 41b.

[0071] 4(b), the second element 10B may further include a fourth conductive layer 54L. At least a portion of the fourth conductive layer 54L is provided on the fourth support portion 34S. In this example, the fourth conductive layer 54L is electrically connected to a wiring layer 54M provided on the base 41. The fourth conductive layer 54L is electrically connected to the second conductive portion 22a.

[0072] 4(b), the second element 10B may further include a fourth other conductive layer 54aL. At least a portion of the fourth other conductive layer 54aL is provided on the fourth other support portion 34aS. In this example, the fourth other conductive layer 54aL is electrically connected to a wiring layer 54aM provided on the base 41. The fourth other conductive layer 54aL is electrically connected to the second conductive other portion 22b.

[0073] 6A and 6B are schematic plan views illustrating the sensor according to the first embodiment. These figures are plan views of the layer including the first resistive member 11 and the second resistive member 12. 6(a), the first detection element 11E may include a first layer 15a and a second layer 15b. The first layer 15a and the second layer 15b have the same material and thickness as the first resistance member 11. The first resistance member 11 is provided between the first layer 15a and the second layer 15b. By providing these layers, warping (deformation) of the first detection element 11E is suppressed.

[0074] 6(b), the second detection element 12E may include a third layer 15c and a fourth layer 15d. The third layer 15c and the fourth layer 15d have the same material and thickness as the second resistance member 12. The second resistance member 12 is provided between the third layer 15c and the fourth layer 15d. By providing these layers, warping (deformation) of the second detection element 12E is suppressed.

[0075] As described above, in this example, a first gap g1 is provided between the first base region 41a and the first resistance member 11, and a second gap g2 is provided between the second base region 41b and the second resistance member 12. In an embodiment, no gap may be provided between the second base region 41b and the second resistance member 12.

[0076] 5, the position of the third resistance member 63 in the second direction (e.g., the X-axis direction) is between the position of the first resistance member 11 in the second direction and the position of the second resistance member 12 in the second direction. The second resistance member 12 is provided at a position far from the first resistance member 11. In the second resistance member 12, the influence of a temperature rise in the first element 10A is suppressed. Even if the third resistance member 63, which has a small temperature coefficient, is provided near the first resistance member 11 (first element 10A), the influence of a temperature rise in the third resistance member 63 can be substantially negligible.

[0077] 3, the base 41 may include a third substrate region 41c. The third substrate region 41c is between the first substrate region 41a and the second substrate region 41b. The third resistor member 63 is provided in, for example, the third substrate region 41c.

[0078] For example, the planar shape of second element 10B in a plane (XY plane) intersecting the first direction (Z-axis direction) is substantially the same as the planar shape of first element 10A in that plane (XY plane).

[0079] Second embodiment FIG. 7 is a schematic view illustrating the sensor according to the second embodiment. 7 is a circuit diagram of a sensor 120 according to an embodiment. As shown in FIG. 7, the sensor 120 includes a first element 10A, a second element 10B, and a third resistor 63.

[0080] The first element 10A includes a first resistive member 11 and a first conductive member 21. The second element 10B includes a second resistive member 12. The second element 12 may include a second conductive member 22. The third resistive member 63 is connected in parallel with the first resistive member 11. The absolute value of the third temperature coefficient of the third resistance R3 of the third resistive member 63 is smaller than the absolute value of the first temperature coefficient of the first resistance R1 of the first resistive member 11. In the sensor 120, the configurations of the first element 10A and the second element 10B may be similar to the configuration of the sensor 110.

[0081] In the sensor 120, a parallel circuit including the first resistive member 11 and the third resistive member 63 is provided. As a result, when the temperature of the first resistive member 11 rises, the electrical resistance of the parallel circuit approaches the electrical resistance of the second resistive member 12. Since the absolute value of the third temperature coefficient of the third resistance R3 of the third resistive member 63 is small, the temperature coefficient of the parallel circuit can be made substantially the same as the temperature coefficient of the second element 10B.

[0082] In this example, the wiring member 64 is connected in series with the third resistance member 63. The third resistance member 63 and the wiring member 64, which are connected in series, are connected in parallel with the first resistance member 11. The wiring resistance R4 of the wiring member 64 is lower than the third resistance R3. The wiring resistance R4 may be ignored in practical use.

[0083] FIG. 8 is a schematic plan view illustrating the sensor according to the second embodiment. As shown in Fig. 8, in the sensor 120 according to the embodiment, a third connection member 63 is provided. The third connection member 63 is electrically connected in parallel to the first resistance portion 11a and the first resistance other portion 11b. In this example, the electrical connection is performed by a wiring member 64 electrically connected to the third connection member 63. In this example, the wiring member 64 intersects with the first element 10A (e.g., the third connection portion 33C) in the Z-axis direction. The wiring member 64 may be a bonding wire.

[0084] In the first and second embodiments, the first resistance R1 of the first resistance member 11 changes due to a temperature rise of the first resistance member 11 caused by the current i1 flowing through the first conductive member 21. The third resistance member 63 is provided to compensate for the changed resistance. This allows the detection target to be detected with high accuracy. The first resistance R1 that changes due to the temperature rise changes according to the state of the gas (detection target) around the first element 10A.

[0085] In the embodiment, the detection target includes at least one selected from the group consisting of, for example, hydrogen, helium, carbon dioxide, methane, and sulfur hexafluoride (SF6), methane, and propane.

[0086] In the embodiment, the operation of the sensor may be linked to a computing device. For example, data on an appropriate value for the resistance value of the third resistive member 63 may be stored in a memory based on the test results of the sensor. Using the test results after the manufacture of the sensor, the shape of the resistive layer that becomes the third resistive member 63 may be deformed by trimming or the like. The resistance of the third resistive member 63 is adjusted. Trimming may be performed, for example, using a laser or the like.

[0087] The embodiment may include the following configurations (e.g., technical solutions). (Configuration 1) a first element including a first resistive member and a first conductive member; A second element including a second resistive member; a third resistor connected in series with the second resistor; Equipped with an absolute value of a third temperature coefficient of a third resistance of the third resistive member is smaller than an absolute value of a first temperature coefficient of a first resistance of the first resistive member; the absolute value of the third temperature coefficient is smaller than the absolute value of the second temperature coefficient of the second resistor of the second resistor element; The third resistance is lower than the second resistance of the sensor.

[0088] (Configuration 2) 2. The sensor of configuration 1, wherein the third resistance is lower than the first resistance.

[0089] (Configuration 3) The sensor according to configuration 1 or 2, further comprising a wiring member electrically connected to the second resistance member and the third resistance member, wherein the wiring resistance of the wiring member is lower than the third resistance member.

[0090] (Configuration 4) a first element including a first resistive member and a first conductive member; A second element including a second resistive member; a third resistor connected in parallel with the first resistor; Equipped with The sensor, wherein an absolute value of a third temperature coefficient of a third resistance of the third resistive element is smaller than an absolute value of a first temperature coefficient of a first resistance of the first resistive element.

[0091] (Configuration 5) a wiring member connected in series to the third resistance member, the third resistor and the wiring member connected in series are connected in parallel to the first resistor, The sensor according to configuration 4, wherein the wiring resistance of the wiring member is lower than the third resistance.

[0092] (Configuration 6) The sensor of configuration 1 or 4, wherein the first resistance of the first resistance member changes due to a rise in temperature of the first resistance member caused by a current flowing through the first conductive member.

[0093] (Configuration 7) The sensor of claim 6 , wherein the first resistance that changes due to the increase in temperature changes depending on a state of a gas surrounding the first element.

[0094] (Configuration 8) The sensor according to any one of configurations 1 to 7, wherein the second element further includes a second conductive member.

[0095] (Configuration 9) Further comprising a substrate including a first substrate region and a second substrate region; the first element is provided in the first substrate region, a first gap is provided between the first base region and the first resistance member; the second element is provided in the second substrate region, The sensor according to any one of configurations 1 to 8, wherein a second direction from the first base region to the second base region intersects with a first direction from the first base region to the first resistance member.

[0096] (Configuration 10) 10. The sensor of claim 9, wherein a second gap is provided between the second substrate region and the second resistive member.

[0097] (Configuration 11) The sensor of configuration 9 or 10, wherein the planar shape of the second element in a plane intersecting the first direction is substantially the same as the planar shape of the first element in the plane.

[0098] (Configuration 12) A sensor described in any one of configurations 9 to 11, wherein the position of the third resistance member in the second direction is between the position of the first resistance member in the second direction and the position of the second resistance member in the second direction.

[0099] (Configuration 13) 13. The sensor according to any one of configurations 1 to 12, wherein the absolute value of the third temperature coefficient is 1 / 3 or less of the absolute value of the first temperature coefficient and 1 / 3 or less of the absolute value of the second temperature coefficient.

[0100] (Configuration 14) the absolute value of the first temperature coefficient is 300 ppm / K or greater; the absolute value of the second temperature coefficient is 300 ppm / K or more; 14. The sensor according to any one of configurations 1 to 13, wherein the absolute value of the third temperature coefficient is 100 ppm / K or less.

[0101] (Configuration 15) 15. The sensor of claim 14, wherein the absolute value of the third temperature coefficient is 50 ppm / K or less.

[0102] (Configuration 16) 16. The sensor according to any one of configurations 1 to 15, wherein the third resistance member includes at least one selected from the group consisting of Ni and Cr.

[0103] (Configuration 17) 17. The sensor according to any one of configurations 1 to 16, wherein the third resistance member contains Ni and Cr, and a composition ratio of Cr in the third resistance member is 30 wt % or more and 80 wt % or less.

[0104] (Configuration 18) 18. The sensor of claim 16 or 17, wherein the first resistive member and the second resistive member include at least one selected from the group consisting of Ti, TiN, Al, W, Si, Cu, Au, Pd, and Pt.

[0105] (Configuration 19) The sensor according to configuration 3 or 5, wherein the wiring member includes at least one selected from the group consisting of aluminum, copper, and gold.

[0106] (Configuration 20) Further comprising a circuit portion, the circuit portion includes a differential amplifier having a first input and a second input; A signal corresponding to the potential of the first resistor is input to the first input; 20. The sensor according to any one of configurations 1 to 19, wherein a signal corresponding to the potential of the second resistive member is input to the second input.

[0107] According to the embodiment, a sensor capable of improving accuracy can be provided.

[0108] The above describes the embodiments of the present invention with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configurations of each element, such as the substrate, element, and processing unit, included in the sensor are included in the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting them from the known range.

[0109] Furthermore, any combination of two or more elements of each of the specific examples, within the scope of technical feasibility, is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0110] In addition, all sensors that can be implemented by a person skilled in the art by appropriately modifying the design based on the sensor described above as an embodiment of the present invention also belong to the scope of the present invention as long as they include the gist of the present invention.

[0111] In addition, within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it will be understood that these modifications and alterations also fall within the scope of the present invention.

[0112] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0113] Reference Signs: 10A, 10B...first and second elements; 11, 12...first and second resistive members; 11E, 12E...first and second detecting elements; 11a, 12a...first and second resistive portions; 11b, 12b...first and second other resistive portions; 15a-15d...first to fourth layers; 18A, 18B...first and second insulating members; 21, 22...first and second conductive members; 21a, 22a...first and second conductive portions; 21b, 22b...first and second other conductive portions; 31C-34C...first to fourth connecting portions; 31S-34S...first to fourth supporting portions; 31aC-34aC...first to fourth other connecting portions; 31aS-34aS...first to fourth other supporting portions; 41...base, 41a-41c...first to third base regions, 41i...insulating film, 41s...substrate, 51L-54L...first to fourth conductive layers, 51M-54M...wiring layer, 51MT-53MT...terminal, 51aL-54aL...first to fourth other conductive layers, 51aM-54aM...wiring layer, 51aMT-53aMT...terminal, 63...third resistance member, 64, 65...wiring member, 70...circuit section, 70s...signal, 71...differential amplifier, 71a, 71b...first and second inputs, 72...AD conversion circuit, 75a, 75b...first and second current sources, 76...power supply, 110, 120...sensor, C1(Cr)...concentration, R1-R3...first to third resistors, R4, R5: Wiring resistance, TCR: Temperature coefficient, g1, g2: 1st and 2nd air gaps, i1: Current, id1, id2: 1st and 2nd detection currents

Claims

1. a first element including a first resistive member and a first conductive member; a second element including a second resistive member; a third resistor connected in series with the second resistor; Equipped with an absolute value of a third temperature coefficient of a third resistance of the third resistive member is smaller than an absolute value of a first temperature coefficient of a first resistance of the first resistive member; the absolute value of the third temperature coefficient is less than the absolute value of the second temperature coefficient of the second resistor of the second resistive element; The third resistance is lower than the second resistance.

2. The sensor of claim 1 , wherein the third resistance is lower than the first resistance.

3. The sensor according to claim 1 , further comprising a wiring member electrically connected to the second resistance member and the third resistance member, wherein a wiring resistance of the wiring member is lower than that of the third resistance member.

4. a first element including a first resistive member and a first conductive member; a second element including a second resistive member; a third resistor connected in parallel with the first resistor; Equipped with The sensor, wherein an absolute value of a third temperature coefficient of a third resistance of the third resistive element is less than an absolute value of a first temperature coefficient of a first resistance of the first resistive element.

5. 5. The sensor according to claim 1, wherein the first resistance of the first resistance member changes due to a rise in temperature of the first resistance member caused by a current flowing through the first conductive member.

6. The sensor of claim 5 , wherein the first resistance that changes with the increase in temperature varies in response to a gas condition surrounding the first element.

7. The sensor according to claim 1 , wherein the second element further comprises a second conductive member.

8. further comprising a substrate including a first substrate region and a second substrate region; the first element is provided in the first base region, a first gap is provided between the first base region and the first resistance member; the second element is provided in the second substrate region, 8. The sensor according to claim 1, wherein a second direction from the first substrate region to the second substrate region intersects with a first direction from the first substrate region to the first resistor member.

9. The sensor of claim 8 , wherein a second gap is provided between the second substrate region and the second resistive member.

10. Further comprising a circuit portion, the circuit portion includes a differential amplifier having a first input and a second input; A signal corresponding to the potential of the first resistor is input to the first input; The sensor according to any one of claims 1 to 9, wherein a signal corresponding to the potential of the second resistive member is input to the second input.

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