JP6436706B2 - Gas sensor, gas detector, and gas sensor manufacturing method - Google Patents

Description

  The present invention provides a gas sensor and a gas detector having a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected has contacted the gas sensitive body, and a heating unit that heats the gas sensitive body. The present invention relates to a method for manufacturing a gas sensor.

  Gas sensors using MEMS technology (Micro Electro Mechanical Systems) have been developed for power saving and miniaturization. In such gas sensors, there are gas sensors, a detection unit (electrode), and a heating unit (heater) provided on a substrate, and the substrate is supported in a suspended state by a plurality of bridging units. This type of gas sensor is advantageous in terms of power saving because it is difficult for heat to escape from the substrate due to its suspended structure.

  In the gas sensor of Patent Document 1, in order to relieve the thermal stress acting on the base when the thin film heater is turned on / off, one thin film heater wiring is reduced compared to the other one of the holes in the center of the sensor, and the dummy wiring Is provided.

JP 2012-98232 A

  The conventional gas sensor has a problem that the output fluctuates due to short-term humidity change, and the sensitivity decreases due to long-term use. The inventor has intensively studied and has come to realize that the cause of these problems is due to temperature non-uniformity on the substrate caused by the above-described suspended structure.

  Among the plurality of bridging portions that support the substrate, the temperature of the bridging portion (first bridging portion) provided with wiring for supplying power to the heater rises due to heat generation of the wiring due to energization and heat conduction from the heater. On the other hand, in the bridging portion where the wiring is not provided (second bridging portion), the temperature rise as in the first bridging portion is not observed. Then, since the outflow of heat through the second bridging portion becomes large, the temperature of the gas sensitive body at the connecting portion between the second bridging portion and the substrate becomes lower than other places.

  As the gas sensitive body, an oxide semiconductor such as tin oxide or a substance having catalytic activity for gas is used. If there is a low-temperature part in the gas sensitive body, it is considered that the sensitivity change due to humidity is large or the sensitivity is gradually affected by humidity and the sensitivity is lowered.

  In a small gas sensor, pulse driving, that is, energization of the heater and gas detection may be intermittently performed to further reduce power consumption. In such a case, it is considered that the above problem appears more remarkably. That is, the gas sensitive body is at room temperature for most of the period and is exposed to moisture in the air. Moisture adhering to the gas sensor during this period should be released during the heating period, but is not sufficiently released in the above-mentioned low temperature portion, and it is considered that moisture gradually accumulates and causes a decrease in sensitivity.

  The present invention has been made in view of the above-described problems, and its object is to provide a gas sensor in which short-term humidity dependence and long-term sensitivity reduction are suppressed, a gas detector using the gas sensor, and a gas sensor It is to provide a manufacturing method.

In order to achieve the above object, the gas sensor according to the present invention includes a gas sensor provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensor, and the gas sensor. A heating unit that heats the substrate, wherein the substrate is supported on a support substrate by a bridging unit connected to a connection end of the substrate, and the bridging unit supplies power to the heating unit. A second connecting end having a first bridging portion provided with an electric wire and a second bridging portion not provided with the power supply line, to which the second bridging portion is connected among the connecting end portions of the substrate. The gas sensitive body non-covering region that is not covered with the gas sensitive body is formed in the portion, and among the connection end portions of the substrate, the first connection end portion to which the first bridging portion is connected is formed. Is that the gas sensitive body is coated .

  Since the power supply line for supplying power to the heating unit is not provided in the second bridging part, when a gas sensitive body is provided at the second connection end to which the second bridging part is connected, the second bridging part is located above the second connection end. The gas sensitive body may be at a lower temperature than the gas sensitive body in other parts. According to said characteristic structure, the gas sensitive body non-coating area | region which is not covered with the gas sensitive body is formed in the 2nd connecting end part to which a 2nd bridge | crosslinking part is connected among the connection end parts of a board | substrate. Therefore, in the gas sensitive body provided on the substrate, the portion that becomes low in temperature when heated by the heating unit becomes small. Then, since the contribution from the above-mentioned low-temperature part to the sensor output by the detection unit becomes smaller, it becomes difficult to be affected by humidity. Therefore, it is possible to realize a gas sensor in which short-term humidity dependency and long-term sensitivity reduction are suppressed.

By providing the gas sensor non-covering region, the total amount or surface area of the gas sensor is smaller than when the gas sensor is provided on the entire surface of the substrate, so that the sensor output itself may be small. However, by providing the gas sensing member non-covering region at the second connection end, the gas sensing element at the low temperature portion becomes small, so that short-term humidity dependence and long-term sensitivity reduction can be suppressed. .
In addition, among the connection end portions of the substrate, the gas connection is formed on the first connection end portion to which the first bridging portion is connected, so that short-term humidity can be achieved while suppressing a decrease in sensor output. It is possible to realize a gas sensor in which dependence and long-term sensitivity decrease are suppressed.
In order to achieve the above object, the gas sensor according to the present invention includes a gas sensor provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensor, and the gas sensor. A gas sensor having a heating unit for heating the insulating layer, wherein an insulating layer is provided so as to cover the heating unit provided on a base constituting the substrate, and a pair of electrodes is provided on the insulating layer. The gas sensitive body is provided on a layer and the pair of electrodes, and the detection unit includes the pair of electrodes, and detects the detection target gas based on a change in resistance value between the pair of electrodes. The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is provided with a power supply line that feeds power to the heating portion. The bridge part and the feeder line A gas-sensitive member that is not covered with the gas-sensitive body at the second connecting end portion to which the second bridging portion is connected among the connecting end portions of the substrate. The body uncovered area is formed.
In order to achieve the above object, the gas sensor according to the present invention includes a gas sensor provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensor, and the gas sensor. A gas sensor having a heating unit for heating the substrate, wherein a resistor having a function as the detection unit and a function as the heating unit is provided on a base constituting the substrate, and the resistor and the base are provided on the base. The gas sensitive body is provided, and the substrate is supported on a support substrate by a bridging portion connected to a connection end portion of the substrate, and the bridging portion feeds the resistor as the heating portion. A second bridging portion that is provided with a power supply line and a second bridging portion that is not provided with the power supply line, and the second bridging portion is connected to the second bridging portion of the connection end portion of the substrate. At the connection end, the gas sensitive It lies in that the gas-sensitive body uncovered regions which are not covered with the is formed.

In order to achieve the above object, the gas sensor according to the present invention includes a gas sensor provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensor, and the gas sensor. A heating unit that heats the substrate, wherein the substrate is supported on a support substrate by a bridging unit connected to a connection end of the substrate, and the bridging unit supplies power to the heating unit. A first bridging portion provided with an electric wire; and a second bridging portion not provided with the power supply line; a center point that is a center in a top view of the substrate; the substrate and the second bridging portion; Among the regions on the substrate that are separated by the perpendicular bisector connecting the connecting points, the gas sensitive material that is not covered with the gas sensitive member is disposed in the second region that is the region on the connecting point side. A body uncovered region is formed, and Of serial connection end, wherein the first connection end portion in which the first bridge portion is connected, in that the gas sensitive body is coated form.

Since the power supply line for supplying power to the heating unit is not provided in the second bridging unit, the temperature of the vicinity of the connection point between the substrate and the second bridging unit decreases due to large heat outflow through the second bridging unit. According to the above characteristic configuration, of the regions in the substrate that are separated by the perpendicular bisector connecting the center point that is the center in the top view of the substrate and the connection point between the substrate and the second bridging portion. In the second region that is the region on the side of the connection point, the gas sensitive member non-covering region that is not covered with the gas sensitive member is formed. The part which becomes low temperature when heated by is reduced. Then, since the contribution from the above-mentioned low-temperature part to the sensor output by the detection unit becomes smaller, it becomes difficult to be affected by humidity. Therefore, it is possible to realize a gas sensor in which short-term humidity dependency and long-term sensitivity reduction are suppressed.
In addition, among the connection end portions of the substrate, the gas connection is formed on the first connection end portion to which the first bridging portion is connected, so that short-term humidity can be achieved while suppressing a decrease in sensor output. It is possible to realize a gas sensor in which dependence and long-term sensitivity decrease are suppressed.
In order to achieve the above object, the gas sensor according to the present invention includes a gas sensor provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensor, and the gas sensor. A gas sensor having a heating unit for heating the insulating layer, wherein an insulating layer is provided so as to cover the heating unit provided on a base constituting the substrate, and a pair of electrodes is provided on the insulating layer. The gas sensitive body is provided on a layer and the pair of electrodes, and the detection unit includes the pair of electrodes, and detects the detection target gas based on a change in resistance value between the pair of electrodes. The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is provided with a power supply line that feeds power to the heating portion. The bridge part and the feeder line A second bisector having a second bridging portion that is not cut, and a vertical bisector connecting a center point that is the center of the substrate in a top view and a connection point between the substrate and the second bridging portion. A gas sensitive body non-covering region that is not covered with the gas sensitive material is formed in a second region, which is a region on the connection point side, in the partitioned region of the substrate.
In order to achieve the above object, the gas sensor according to the present invention includes a gas sensor provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensor, and the gas sensor. A gas sensor having a heating unit for heating the substrate, wherein a resistor having a function as the detection unit and a function as the heating unit is provided on a base constituting the substrate, and the resistor and the base are provided on the base. The gas sensitive body is provided, and the substrate is supported on a support substrate by a bridging portion connected to a connection end portion of the substrate, and the bridging portion feeds the resistor as the heating portion. A first bridging portion provided with a feeder line to be provided and a second bridging portion not provided with the feeder line, a center point being a center in a top view of the substrate, the substrate and the second bridge Line segment connecting with the connection point A gas-sensitive body non-covered area that is not covered with the gas sensitive body is formed in a second area that is the area on the connection point side of the area on the substrate that is divided by a vertical bisector. In the point.

Another characteristic configuration of the gas sensor according to the present invention is that, among the connection end portions of the substrate, a first connection end portion to which the first bridging portion is connected is coated with the gas sensitive body. It is in.

According to the above characteristic configuration, the gas connection is formed on the first connection end to which the first bridging portion is connected among the connection ends of the substrate, so that a decrease in sensor output is suppressed. In addition, it is possible to realize a gas sensor in which short-term humidity dependency and long-term sensitivity deterioration are suppressed.

  Another characteristic configuration of the gas sensor according to the present invention is that the gas sensitive body non-covering region has a gas low sensitive body whose sensitivity to the detection target gas is smaller than the gas sensitive body, or a sensitivity to the detection target gas. A gas insensitive body having no coating is formed by coating.

  According to the above characteristic configuration, the gas sensitive body non-covering region has a gas low sensitive body whose sensitivity to the detection target gas is smaller than that of the gas sensitive body, or a gas insensitive body which does not have sensitivity to the detection target gas. Since the coating is formed on the substrate, the contribution to the sensor output from the low-temperature portion on the substrate is effectively reduced by the presence of the gas low-sensitivity body or the gas non-sensitivity body, while the substrate is gas-sensitive or gas-sensitive. By covering with a non-sensitive body, it is possible to realize a gas sensor with excellent environmental resistance by suppressing corrosion and deterioration of the substrate and the detection part. In addition, since the gas-sensitive body non-covering area of the substrate is covered with a gas low-sensitivity body or gas-insensitive area, heat dissipation from the gas-sensitive body non-covering area is suppressed, the substrate is kept at an appropriate temperature, Detection can be performed stably.

  Another characteristic configuration of the gas sensor according to the present invention is that a high-resistance body having an electric resistance larger than that of the gas-sensitive body is formed on the gas-sensitive body uncoated region.

  In a semiconductor gas sensor or a hot wire semiconductor gas sensor, an oxide semiconductor is used as a gas sensitive body. When the oxide semiconductor heated by the heating unit comes into contact with the detection target gas, the electrical resistance value of the oxide semiconductor changes. The change is detected by the detection unit and becomes an output of the gas sensor. Therefore, when a high resistance body having a larger electric resistance than that of the gas sensitive body is provided on the substrate, the contribution to the sensor output from the portion is reduced.

  That is, according to the above characteristic configuration, since the high-resistance body having a larger electric resistance than that of the gas sensitive body is coated in the non-coated region of the gas sensitive body, the sensor output from the low temperature portion on the substrate is performed. The gas sensor excellent in environmental resistance can be realized by suppressing the corrosion and deterioration of the substrate and the detection unit by covering the substrate with the high resistance body, while effectively reducing the contribution of the high resistance body. In addition, since the gas-sensitive body non-covering area of the substrate is covered with a gas low-sensitivity body or gas-insensitive area, heat dissipation from the gas-sensitive body non-covering area is suppressed, the substrate is kept at an appropriate temperature, Detection can be performed stably.

  Another characteristic configuration of the gas sensor according to the present invention is that the high-resistance element has an insulating oxide as a main component.

  According to the above characteristic configuration, since the high resistance element is mainly composed of an insulating oxide, it contributes to the sensor output from the low temperature part on the substrate with a long-term stable material that is not easily affected by the environment. A gas sensor having excellent environmental resistance can be realized by covering the substrate with the material while effectively reducing the substrate. As the insulating oxide, for example, alumina, silica, magnesia, zirconia, titania and the like can be used.

  Another characteristic configuration of the gas sensor according to the present invention is that the gas sensitive body includes an oxide semiconductor as a main component.

  According to the above characteristic configuration, the gas sensor is composed mainly of an oxide semiconductor, so a gas sensor that uses a highly sensitive gas sensor and suppresses short-term humidity dependence and long-term sensitivity degradation is realized. it can. As the oxide semiconductor, for example, a transition metal oxide such as zinc oxide, titanium oxide, or iron oxide, or a semiconductor material mainly containing a metal oxide such as gallium oxide, germanium oxide, indium oxide, tin oxide, or antimony oxide is used. Can be used.

  Another characteristic configuration of the gas sensor according to the present invention is that the gas sensitive body has a catalytic activity for promoting the combustion of the gas to be detected in contact with the gas sensor, and the gas sensitive body is not covered with the gas sensitive body uncovered region at the second connection end. Is that a catalyst low-activity having a catalytic activity lower than that of the gas-sensitive material or a catalyst inactive having no catalytic activity is formed by coating.

  In the contact combustion type gas sensor, a material having catalytic activity for accelerating the combustion of the detection target gas is used as the gas sensitive body. When the gas sensing element heated by the heating unit comes into contact with the detection target gas, oxidation (combustion) of the detection target gas occurs on the surface of the gas sensing element, and the temperature of the gas sensing element increases due to the combustion heat. This temperature rise is detected by the detector as an increase in electrical resistance, and becomes a sensor output. Therefore, when a catalyst low activity body having a lower catalyst activity than that of the gas sensitive body or a catalyst inactive body having no catalyst activity is provided on the substrate, the contribution to the sensor output from the portion is reduced.

  That is, according to the above-described characteristic configuration, in the gas-sensitive body non-covering region at the second connection end, a catalytic low-activity body having a catalytic activity lower than that of the gas-sensitive body, or a catalyst inactive body having no catalytic activity. Since the coating is formed on the substrate, the contribution to the sensor output from the low-temperature portion on the substrate is effectively reduced by the presence of the catalyst low-activity or non-catalyst, and the substrate is reduced to the catalyst low-activity or catalyst. By covering with a non-active material, a gas sensor having excellent environmental resistance can be realized.

  Another characteristic configuration of the gas sensor according to the present invention is that the catalyst low-activity or the catalyst deactivation is mainly composed of a metal oxide.

  According to the above characteristic configuration, since the catalyst low-activity or the catalyst deactivation is mainly composed of a metal oxide, a sensor from a portion that is low in temperature on the substrate by a material that is not easily affected by the environment and is stable for a long time. A gas sensor having excellent environmental resistance can be realized by covering the substrate with the material while effectively reducing the contribution to output. In addition, since the gas-sensitive body non-covering area of the substrate is covered with a gas low-sensitivity body or gas-insensitive area, heat dissipation from the gas-sensitive body non-covering area is suppressed, the substrate is kept at an appropriate temperature, Detection can be performed stably. As the metal oxide, for example, alumina, magnesia, zirconia, titania or the like can be used.

  Another characteristic configuration of the gas sensor according to the present invention is that the gas sensitive body contains a noble metal catalyst supported on a metal oxide.

  According to the above characteristic configuration, since the gas sensitive body contains the noble metal catalyst supported on the metal oxide, short-term humidity dependence and long-term sensitivity decrease are suppressed while using the highly sensitive gas sensitive body. Gas sensor can be realized. As the metal oxide, for example, alumina, magnesia, zirconia, titania and the like can be used. As the noble metal catalyst, for example, a platinum group element (ruthenium, rhodium, palladium, osmium, iridium, platinum) can be used.

  Another characteristic configuration of the gas sensor according to the present invention is that the heating unit heats the gas sensitive body to a predetermined detection temperature or higher during measurement, and the detection temperature is 350 ° C. or higher and 550 ° C. or lower.

  According to the above characteristic configuration, the heating unit heats the gas sensitive body to a predetermined detection temperature or higher during measurement, and the detection temperature is 350 ° C. or higher and 550 ° C. or lower. It is possible to realize a gas sensor in which short-term humidity dependence and long-term sensitivity decrease are suppressed while maintaining high sensitivity.

    A characteristic configuration of a gas detector according to the present invention for achieving the above object is characterized in that the gas detector includes an output unit that outputs gas information related to the detection target gas based on the output of the gas sensor and the gas sensor. To do.

  According to said characteristic structure, since it has the output part which outputs the gas information relevant to the said detection target gas based on the above-mentioned gas sensor and the output of the said gas sensor, a short-term humidity dependence and a long-term sensitivity fall A gas detector that is suppressed and has high reliability can be realized.

In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A first bridging portion provided with a feeding line for feeding power to the heating portion; and a second bridging portion not provided with the feeding line, wherein the second bridging portion is connected among the connection end portions of the substrate. Forming a gas-sensitive-body non-covering region that is not covered with the gas-sensitive body at the second connection end and connecting the first bridging portion to the first connection end of the connection end of the substrate. in the form of forming the gas sensitive body, the gas-sensitive Certain materials that it has a deposition step of depositing on the substrate.

According to the above characteristic configuration, the gas sensitive material is deposited on the substrate in a form in which the gas sensitive material non-covering region is formed at the second connection end by the adhesion process. Of the gas sensitive body, a gas sensor having a smaller part that becomes low temperature when heated by the heating unit is manufactured. Then, since the contribution from the above-mentioned low-temperature part to the sensor output by the detection unit becomes smaller, it becomes difficult to be affected by humidity. Therefore, it is possible to manufacture a gas sensor in which short-term humidity dependency and long-term sensitivity reduction are suppressed.
In addition, among the connection end portions of the substrate, the gas connection is formed on the first connection end portion to which the first bridging portion is connected, so that short-term humidity can be achieved while suppressing a decrease in sensor output. It is possible to realize a gas sensor in which dependence and long-term sensitivity decrease are suppressed.
In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A step of forming the heating unit on a base constituting the substrate, the first bridging unit provided with a power supply line for supplying power to the heating unit, and a second bridging unit not provided with the power supply line; A step of forming an insulating layer so as to cover the heating portion, a step of forming a pair of electrodes on the insulating layer, and a second connection portion of the connection end portion of the substrate to which the second bridging portion is connected. 2 The connection end is covered with the gas sensitive body A gas sensing member non-covering region is formed, and the gas sensing member material is deposited on the insulating layer and the pair of electrodes, and the detection unit has the pair of electrodes. However, the detection target gas is detected based on a change in resistance value between the pair of electrodes.
In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A first bridging portion provided with a feed line for feeding power to the heating portion; and a second bridging portion not provided with the feed line; a function as the detection unit on a base constituting the substrate; A step of forming a resistor having a function as a heating unit, and a gas not covered by the gas sensitive body at a second connection end to which the second bridging portion is connected, of the connection ends of the substrate; Form to form non-sensitive body coating area , In that it has a deposition step of depositing a material of said gas sensitive body on said resistor and said base.

In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A second bridge part provided with a power supply line for supplying power to the heating part and a second bridge part not provided with the power supply line, and a second bridge part connected to the second bridge part among the connection end parts; A first attachment step of attaching a gas low-sensitivity body whose sensitivity to the detection target gas is smaller than that of the gas sensitivity body or a gas insensitivity body having no sensitivity to the detection target gas on the connection end. And the material of the gas sensitive body Lies in that a second attaching step of attaching on said substrate including a first connection end portion to which the first bridge portion of the connection end portion is connected.

According to said characteristic structure, on the 2nd connection end part, the gas insensitive body which does not have the sensitivity with respect to a detection object gas, or the gas low sensitivity body whose sensitivity with respect to a detection object gas is smaller than a gas sensitive body A first adhesion step for depositing gas and a second deposition step for depositing the material of the gas sensitive body on the substrate, so that the region (second connection end portion) covered with the gas low sensitive body or the gas insensitive body Gas sensitive material does not adhere to the region including As a result, a gas sensor having a smaller part that becomes a low temperature when heated by the heating unit among the gas sensitive elements provided on the substrate is manufactured. Then, since the contribution from the above-mentioned low-temperature part to the sensor output by the detection unit becomes smaller, it becomes difficult to be affected by humidity. Therefore, it is possible to manufacture a gas sensor in which short-term humidity dependency and long-term sensitivity reduction are suppressed.
In addition, among the connection end portions of the substrate, the gas connection is formed on the first connection end portion to which the first bridging portion is connected, so that short-term humidity can be achieved while suppressing a decrease in sensor output. It is possible to realize a gas sensor in which dependence and long-term sensitivity decrease are suppressed.
In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A second bridge part provided with a power supply line for supplying power to the heating part and a second bridge part not provided with the power supply line, and a second bridge part connected to the second bridge part among the connection end parts; On the connection end, the catalytic activity for promoting the combustion of the gas to be detected in contact is lower than that of the gas sensitive body, or the catalytic activity for promoting the combustion of the gas to be detected in contact is provided. No catalyst deactivator deposition An adhesion process, and a second adhesion process in which the material of the gas sensitive body is adhered on the substrate including the first connection end portion to which the first bridging portion is connected among the connection end portions. is there.
In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A step of forming the heating unit on a base constituting the substrate, the first bridging unit provided with a power supply line for supplying power to the heating unit, and a second bridging unit not provided with the power supply line; A step of forming an insulating layer so as to cover the heating portion, a step of forming a pair of electrodes on the insulating layer, and a second connection end to which the second bridging portion of the connection ends is connected Sensitivity to the detection target gas A first deposition step of depositing a gas low-sensitivity body smaller than the gas-sensitive body or a gas-insensitive body having no sensitivity to the detection target gas; and the material of the gas-sensitive body as the insulating layer and the pair A second attaching step for attaching the electrode to the first electrode, wherein the detection unit includes the pair of electrodes and detects the detection target gas based on a change in resistance value between the pair of electrodes. It is in the point comprised as follows.
In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A first bridging portion provided with a feed line for feeding power to the heating portion; and a second bridging portion not provided with the feed line; a function as the detection unit on a base constituting the substrate; The step of forming a resistor having a function as a heating unit, and the combustion of the detection target gas in contact with the second connection end of the connection end connected to the second bridging unit are promoted. Catalytic activity is better than the gas A first depositing step of depositing a low catalyst low-activity or a catalyst deactivator having no catalytic activity that promotes combustion of the gas to be detected in contact; and a material of the gas-sensitive body comprising the resistor and the base And a second deposition step for depositing on the substrate.

In order to achieve the above object, the characteristic configuration of the gas sensor manufacturing method according to the present invention includes a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected is in contact with the gas sensitive body, A gas sensor manufacturing method having a heating unit for heating a gas sensitive body, wherein the substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate, and the bridging portion is A second bridge part provided with a power supply line for supplying power to the heating part and a second bridge part not provided with the power supply line, and a second bridge part connected to the second bridge part among the connection end parts; A masking step of covering the connection end with a masking material, an attachment step of attaching the material of the gas sensitive body on the substrate after the masking step, and a step of removing the masking material after the attachment step. In terms of having .

  According to the above characteristic configuration, since the second connecting end portion is covered with the masking material, and the masking material is covered with the masking material since the gas sensing material is attached to the substrate after the masking step. The gas sensitive material does not adhere to the region (the region including the second connection end). As a result, a gas sensor having a smaller part that becomes a low temperature when heated by the heating unit among the gas sensitive elements provided on the substrate is manufactured. Then, since the contribution from the above-mentioned low-temperature part to the sensor output by the detection unit becomes smaller, it becomes difficult to be affected by humidity. Therefore, it is possible to manufacture a gas sensor in which short-term humidity dependency and long-term sensitivity reduction are suppressed.

Perspective view showing structure of gas sensor Sectional view showing the structure of the gas sensor Top view of the semiconductor gas sensor according to the first embodiment Top view of the semiconductor gas sensor according to the first embodiment Sectional drawing of the semiconductor type gas sensor which concerns on 1st Embodiment Top view of a semiconductor gas sensor according to the second embodiment Sectional drawing of the semiconductor type gas sensor which concerns on 2nd Embodiment Top view at the time of manufacture of the semiconductor type gas sensor concerning a 2nd embodiment The top view of the contact combustion type gas sensor concerning a 3rd embodiment Top view of a semiconductor gas sensor according to the fourth embodiment Top view of a semiconductor gas sensor according to the fourth embodiment Top view of a semiconductor gas sensor according to the fifth embodiment Sectional drawing of the semiconductor type gas sensor which concerns on 5th Embodiment The top view of the semiconductor type gas sensor which concerns on the modification of 5th Embodiment. Sectional drawing of the semiconductor type gas sensor which concerns on the modification of 5th Embodiment. Top view of semiconductor gas sensor of Comparative Example 1 Graph showing test results of short-term humidity effects Graph showing long-term humidity effect test results Graph showing long-term humidity effect test results Top view of the catalytic combustion type gas sensor of Comparative Example 2 Graph showing long-term humidity effect test results Graph showing long-term humidity effect test results

<First Embodiment>
First, the structure and operation of the semiconductor gas sensor 1a (gas sensor 1) according to the first embodiment will be described with reference to FIGS. As shown in FIGS. 1 and 2, in the semiconductor gas sensor 1 a, the substrate 10 on which the gas sensitive body 50 is provided on the upper surface is suspended by the first bridging portion 21 and the second bridging portion 22, and the support substrate 2. Supported by The lower side of the substrate 10 is a cavity 3. The entire structure of the semiconductor gas sensor 1a is formed by the MEMS technology. For example, silicon is used for the support substrate 2.

2 is a cross-sectional view taken along II-II in FIG. As shown in FIG. 2, the substrate 10 includes a base 11, a thin film heater 30 and an insulating layer 12 that are sequentially stacked on the base 11. A pair of electrodes 41 and 42 (detecting unit 40) and a gas sensitive body 50 are laminated on the substrate 10. For example, SiO ₂ is used for the base 11 and the insulating layer 12, and platinum or the like is used for the heater 30 and the electrodes 41 and 42. For the gas sensitive body 50, a semiconductor material whose electric resistance value varies depending on the presence and concentration of the detection target gas is used, for example, a material mainly composed of tin oxide, indium oxide, zinc oxide, titanium oxide, or the like. .

  The pair of electrodes 41 and 42 are formed in a comb-like shape, and are arranged at a certain interval in such a manner that the comb teeth of the other electrode enter the gap between the comb teeth of one electrode.

  The heater 30 is supplied with power through a power supply line 23 provided in the first bridging portion 21, generates heat, and heats the gas sensitive body 50. When the heated gas sensitive body 50 comes into contact with the detection target gas, the resistance value changes. The pair of electrodes 41 and 42 are arranged to face each other in contact with the gas sensitive body 50, and when the resistance value of the gas sensitive body changes, the resistance value between the electrode 41 and the electrode 42 changes. The change in resistance value is taken out through a detection line 24 provided in the second bridging portion 22 and converted into an output of the semiconductor gas sensor 1a by a detection circuit or the like (not shown).

  The heating / detection operation described above is performed by so-called intermittent driving or pulse driving for the purpose of power saving, and is performed at a predetermined interval of about 20 to 60 seconds in an extremely short time of about 100 μsec to 100 msec. Is called. For example, it is performed for 100 msec with an interval of 30 seconds. The heater 30 heats the gas sensitive body 50 to a predetermined detection temperature or higher. The detection temperature is determined according to the material used as the gas sensitive body 50, and is set in the range of 350 ° C to 550 ° C. For example, when detecting methane gas using tin oxide for the gas sensitive body 50, it is appropriate that the detection temperature is 400 ° C to 500 ° C.

  Next, the first connection end portion 13, the second connection end portion 14, and the gas sensor non-covering region 15 of the substrate 10 will be described with reference to FIGS. 3 to 5.

  FIG. 3 is a top view showing a state where the electrodes 41 and 42 are arranged on the substrate 10. The four corners of the substrate 10 are connected to the first bridging portion 21 and the second bridging portion 22. Specifically, the first bridging portion 21 and the substrate 10 are connected at the two first connection end portions 13 located on the diagonal line of the substrate 10, and two second positions located on the diagonal line of the substrate 10. The second bridging portion 22 and the substrate 10 are connected at the connection end portion 14.

  As described above, the first bridging portion 21 is provided with the feeder line 23 that is connected to the heater 30 and feeds power. A detection line 24 connected to the electrodes 41 and 42 is disposed in the second bridging portion 22. Here, when the gas sensing member 50 is heated by energizing the heater 30, the temperature of the first bridging portion 21 rises due to heat generation of the power supply line 23 itself or heat conduction from the heater 30 to the power supply line 23.

  On the other hand, the second bridging portion 22 is not provided with an object that generates heat unlike the power supply line 23, and thus the temperature rise as in the first bridging portion 21 is not observed. Then, the outflow of heat from the substrate 10 to the support substrate 2 through the second bridging portion 22 increases. As a result, the second connecting end portion 14 of the substrate 10 to which the second bridging portion 22 is connected is the center portion of the substrate 10 or the first connecting end portion 13 of the substrate 10 to which the first bridging portion 21 is connected. Than the temperature.

Therefore, in order to suppress short-term humidity dependence and long-term sensitivity degradation due to a decrease in the temperature of a part of the gas sensitive body 50, the gas sensitive body 50 is covered with the second connection end 14 of the substrate 10. An uncovered gas-sensitive body uncovered region 15 is formed. As shown in FIGS. 4 and 5 , in the first embodiment, the entire surface of the substrate 10 is not covered with the gas sensitive body 50, but alumina 51 is provided in the gas sensitive body non-covering region 15.

  The alumina 51 is a gas insensitive body having no sensitivity to the detection target gas. The alumina 51 is a high resistance body having a larger electrical resistance than the gas sensitive body 50. Instead of the alumina 51, a gas low-sensitivity body whose sensitivity to the detection target gas is smaller than that of the gas sensitive body 50 may be provided in the gas-sensitive body uncoated region 15. For the low gas sensitivity body, a material having a small sensitivity to the detection target gas by reducing the content of the additive element in the oxide semiconductor having sensitivity to the detection target gas may be used. Further, in place of the alumina 51, an insulating oxide, for example, a metal oxide such as zirconia, magnesia, titania, or silica may be used.

  As described above, in the semiconductor gas sensor 1 a (gas sensor 1) according to the first embodiment, the second connection end portion 14 that becomes low temperature when heated by the heater 30 is made of alumina 51 instead of the gas sensitive body 50. Covered. That is, a gas sensitive body non-covering region 15 that is not covered with the gas sensitive body 50 is formed at the second connection end portion 14. Therefore, compared with the case where the entire surface of the substrate 10 is covered with the gas sensitive body 50, the portion that is at a lower temperature is smaller. As a result, the contribution of the low temperature portion is small with respect to the change in the resistance value of the gas sensitive body 50 detected by the pair of electrodes 41 and 42. Therefore, it is possible to realize the semiconductor gas sensor 1a in which the short-term humidity dependency and the long-term sensitivity decrease are suppressed.

  The area occupied by the gas-sensitive body non-covering region 15 is suitably 5% or more and 13% or less of the area of the substrate 10 in the top view with respect to one second bridging portion 22.

  The first connection end portion 13 is not limited to a point on the substrate 10 where the substrate 10 and the first bridging portion 21 are in contact with each other, but a part including the vicinity thereof. The second connection end portion 14 is not limited to a point on the substrate 10 where the substrate 10 and the second bridging portion 22 are in contact with each other, but a part including the vicinity thereof.

  In the semiconductor gas sensor 1a according to the first embodiment, the second bridging portion 22 is connected to the apex of the substrate 10 that is square in a top view, but the point (the apex of the substrate 10) is a predetermined vertex. It can also be said that the gas-sensitive body non-covering region 15 is formed in a fan-shaped region having a radius of. In addition, it can be said that the gas sensitive body non-covering region 15 is formed within a predetermined distance from the point where the second bridging portion 22 is connected to the substrate 10 in a top view. As described above, the temperature drop due to the outflow of heat from the second bridging portion 22 adversely affects the performance of the gas sensor 1, and the region at a predetermined distance from the point where the substrate 10 and the second bridging portion 22 are connected is the substrate. It is thought that the temperature of 10 falls. By providing the gas-sensitive body non-covering area 15 in this area, the temperature-sensitive portion of the gas-sensitive body 50 can be reduced, and the short-term humidity dependence and long-term sensitivity reduction of the gas sensor 1 can be suppressed. . The above-mentioned sector radius or predetermined distance is necessary for detecting the structure of the gas sensor 1 such as the substrate 10, the first bridging portion 21, the second bridging portion 22, the physical properties of the gas sensitive body 50, and the detection target gas. It can be appropriately determined depending on the temperature.

  Next, a method for manufacturing the semiconductor gas sensor 1a according to the first embodiment will be described.

As a first step, the silicon wafer to be the support substrate 2 is oxidized to form an insulating layer of SiO ₂ to be the base 11, the first bridging portion 21, and the second bridging portion 22.

  As a second step, a platinum film is formed on the insulating layer by sputtering to form a heater 30 of about 1 mm square.

As a third step, a SiO ₂ insulating layer (insulating layer 12) is formed to cover the heater 30.

  As a fourth step, a pair of electrodes 41 and 42 is formed by depositing platinum on the insulating layer 12 by a sputtering method.

  As a fifth step, the cavity 3 is formed by etching the silicon wafer. At this time, a pattern of the heater 30 and the electrodes 41 and 42 is formed using a mask or the like as appropriate.

  As a sixth step, the alumina 51 is formed on the second connection end portion 14 by a printing method (first attaching step). For example, the alumina 51 is formed on the region indicated by reference numeral 51 in FIG.

  As a seventh step, the gas sensitive body 50 is formed on the substrate 10 by a printing method (second attaching step).

  Since the alumina 51 is formed on the second connection end 14 by the sixth step, when the gas sensitive body 50 is formed on the substrate 10 in the seventh step, the alumina 51 is formed on the second connection end 14. The gas sensitive body 50 is not formed. That is, the material of the gas sensitive body 50 is formed on the substrate 10 in the form in which the gas sensitive body non-covered region 15 that is not covered with the gas sensitive body 50 is formed in the second connection end 14 by the sixth step and the seventh step. (Attachment process).

Second Embodiment
A semiconductor gas sensor 1a (gas sensor 1) according to the second embodiment will be described with reference to FIGS. FIG. 6 is a top view of the substrate 10 of the semiconductor gas sensor 1a (gas sensor 1) according to the second embodiment, and FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. In addition, description is abbreviate | omitted about the structure which is common in 1st Embodiment.

  In the first embodiment, the alumina 51 is provided in the gas-sensitive body non-covering region 15, but in the second embodiment, the alumina 51 is not provided. That is, in the second embodiment, the gas sensitive body non-covering region 15 that is not covered with the gas sensitive body 50 is formed in the second connection end portion 14 to which the second bridging portion 22 is connected.

  Next, a method for manufacturing the semiconductor gas sensor 1a according to the second embodiment will be described. The first to fourth steps are the same as in the first embodiment.

  As a fifth step, a masking tape T is pasted on the pair of electrodes 41 and 42 of the substrate 10 so as to cover the second connection end 14 as shown in FIG. 8 (masking step).

  As a sixth step, the gas sensitive body 50 is formed on the substrate 10 by a printing method (attachment step).

  As a seventh step, the masking tape T is removed from the substrate 10.

  Since the masking tape T is affixed on the 2nd connection end part 14 by the 5th process, when forming the gas sensitive body 50 on the board | substrate 10 at a 6th process, the 2nd connection end part 14 of FIG. The gas sensitive body 50 is not formed on the top. That is, the material of the gas sensitive body 50 is formed on the substrate 10 in the form in which the gas sensitive body non-covered region 15 that is not covered with the gas sensitive body 50 is formed in the second connection end 14 by the fifth step and the sixth step. (Attachment process).

<Third Embodiment>
A catalytic combustion type gas sensor (gas sensor 1) according to a third embodiment will be described with reference to FIG. FIG. 9 is a top view of the substrate 10 of the catalytic combustion gas sensor (gas sensor 1) according to the third embodiment. In addition, description is abbreviate | omitted about the structure which is common in 1st Embodiment.

  In the first embodiment, a semiconductor material whose electric resistance value varies depending on the presence or concentration of the detection target gas is used as the gas sensitive body 50, and the resistance value change is detected by the pair of electrodes 41 and 42. In the catalytic combustion type gas sensor of the third embodiment, a material having catalytic activity that promotes the combustion of the contacted detection target gas is used as the gas sensitive body 50, and the temperature rise of the gas sensitive body 50 due to the combustion heat of the detection target gas. Is detected as a change in resistance value of the resistor 43 (detector 40). As the gas sensitive body 50, for example, a noble metal catalyst is used, and palladium supported on alumina is preferably used.

  As shown in FIG. 9, the resistor 43 is provided in a continuous manner while meandering from one of the four corners to the diagonal of the substrate 10. The resistor 43 has a function as the detection unit 40 that detects a temperature change of the gas sensitive body 50 and a function as a heating unit that heats the gas sensitive body 50 as described above. For the resistor 43, for example, platinum, tungsten, gold or the like is used.

  The resistor 43 is supplied with power through the power supply detection line 25, generates heat, and heats the gas sensitive body 50. And the resistance value change of the resistor 43 is taken outside through the electric power feeding detection line 25, and is converted into the output of a contact combustion type gas sensor by the detection circuit etc. which are not shown in figure. That is, the power supply detection line 25 has the functions of the power supply line 23 and the detection line 24 of the first embodiment.

  As shown in FIG. 9, the four corners of the substrate 10 are connected to the first bridging portion 21 and the second bridging portion 22. Specifically, the first bridging portion 21 and the substrate 10 are connected at the two first connection end portions 13 located on the diagonal line of the substrate 10, and two second positions located on the diagonal line of the substrate 10. The second bridging portion 22 and the substrate 10 are connected at the connection end portion 14.

  In the third embodiment, a power supply detection line 25 that is connected to the resistor 43 and supplies power is disposed in the first bridging portion 21. Unlike the first embodiment, the detection line 24 is not disposed in the second bridging portion 22. When the gas sensitive body 50 is heated by energizing the resistor 43, the temperature of the first bridging portion 21 rises due to heat generated by the power supply detection line 25 itself or heat conduction from the resistor 43 to the power supply detection line 25. On the other hand, no temperature rise is observed in the second bridging portion 22 and heat outflow through the second bridging portion 22 is increased. As a result, the second connecting end portion 14 of the substrate 10 to which the second bridging portion 22 is connected is the center portion of the substrate 10 or the first connecting end portion 13 of the substrate 10 to which the first bridging portion 21 is connected. Than the temperature.

  Therefore, in order to suppress short-term humidity dependence and long-term sensitivity degradation due to a decrease in the temperature of a part of the gas sensitive body 50, the gas sensitive body 50 is covered with the second connection end 14 of the substrate 10. An uncovered gas-sensitive body uncovered region 15 is formed. As shown in FIG. 9, in the third embodiment, the entire surface of the substrate 10 is not covered with the gas sensitive body 50, but alumina 51 is provided in the gas sensitive body non-covering region 15.

  The alumina 51 is a catalyst inactive body that does not have catalytic activity for the detection target gas. Instead of the alumina 51, a catalyst low activity material whose catalytic activity for the detection target gas is lower than that of the gas sensitive material 50 may be provided in the gas sensitive material uncoated region 15. As the catalyst low-activity, a material in which the catalytic activity with respect to the detection target gas is reduced by reducing the content or specific surface area of the catalyst noble metal may be used. Moreover, it can replace with the alumina 51 and can use an alumina, a magnesia, a zirconia, a titania etc. as a metal oxide, for example.

  As described above, in the catalytic combustion type gas sensor (gas sensor 1) according to the third embodiment, the second connection end portion 14 that becomes a low temperature when heated by the resistor 43 is replaced with the gas sensitive body 50 and the alumina 51. Covered with. That is, a gas sensitive body non-covering region 15 that is not covered with the gas sensitive body 50 is formed at the second connection end portion 14. Therefore, compared with the case where the entire surface of the substrate 10 is covered with the gas sensitive body 50, the portion that is at a lower temperature is smaller. As a result, the contribution of the low temperature portion is reduced with respect to the temperature change of the gas sensitive body 50 detected by the resistor 43. Therefore, it is possible to realize a catalytic combustion type gas sensor in which short-term humidity dependency and long-term sensitivity reduction are suppressed.

  Next, the manufacturing method of the catalytic combustion type gas sensor (gas sensor 1) which concerns on 3rd Embodiment is demonstrated.

As a first step, the silicon wafer to be the support substrate 2 is oxidized to form an insulating layer of SiO ₂ to be the base 11, the first bridging portion 21, and the second bridging portion 22.

  As a second step, the resistor 43 is formed by depositing platinum on the insulating layer by a sputtering method.

  As a third step, the cavity 3 is formed by etching the silicon wafer. At this time, the pattern of the resistor 43 is formed using a mask or the like as appropriate.

  As a fourth step, an alumina 51 is formed on the second connection end portion 14 by a printing method (first attaching step). For example, the alumina 51 is formed on the region indicated by reference numeral 51 in FIG.

  As a fifth step, the gas sensitive body 50 is formed on the substrate 10 by a printing method (second adhesion step).

  Since the alumina 51 is coated on the second connection end portion 14 in the fourth step, when the gas sensitive body 50 is formed on the substrate 10 in the fifth step, the second connection end portion 14 The gas sensitive body 50 is not coated on top. That is, the material of the gas sensitive body 50 is formed on the substrate 10 in the form in which the gas sensitive body non-covered region 15 that is not covered with the gas sensitive body 50 is formed in the second connection end 14 by the fourth step and the fifth step. (Attachment process).

<Fourth embodiment>
A semiconductor gas sensor 1a (gas sensor 1) according to the fourth embodiment will be described with reference to FIGS. In addition, description is abbreviate | omitted about the structure which is common in 1st Embodiment.

  In the first embodiment described above, by providing the gas sensitive body non-covering region 15 at the second connection end portion 14, the gas sensitive body 50 is provided with a portion that becomes low temperature due to the outflow of heat from the second bridging portion 22. It is small. Thereby, the contribution to the sensor output from the low temperature part influenced by humidity is made small, and the semiconductor gas sensor 1a in which short-term humidity dependence and long-term sensitivity reduction are suppressed is realized.

  In the fourth embodiment, the following configuration is adopted to further suppress short-term humidity dependence and long-term sensitivity degradation. That is, the heater 30 heats the gas sensitive body 50 to a predetermined detection temperature or higher during measurement. As shown in FIG. 11, the gas sensitive body 50 has an appropriate temperature portion 16 that becomes a temperature equal to or higher than the detection temperature at the time of measurement, and a low temperature portion 17 that becomes a temperature lower than the detection temperature at the time of measurement. The low temperature portion 17 is configured such that at least one of the pair of electrodes 41 and 42 is not disposed.

  Then, the gas sensitive body 50 in the low temperature region 17 has a larger distance to one electrode than the appropriate temperature region 16. Then, when the semiconductor gas sensor 1a detects the detection target gas based on a change in the resistance value between the pair of electrodes 41 and 42, the contribution of the low temperature portion 17 to the detection output is smaller than that of the appropriate temperature portion 16.

When the explanation is added, the resistance value between the pair of electrodes 41 and 42 in the semiconductor gas sensor 1a is obtained by using the resistance values of all paths from one electrode through a part of the gas sensitive body 50 to the other electrode. , Given by their combined resistance in parallel. That is, the interelectrode resistance value R is calculated as follows using each path resistance value ri.
1 / R = 1 / r1 + 1 / r2 + 1 / r3 + (Formula 1)
Here, when the path resistance value ri increases, the value of 1 / ri decreases, so that the degree of influence on R when the value of ri changes decreases.

  Since at least one electrode is not disposed in the low temperature region 17, the gas sensitive body 50 in the low temperature region 17 has a larger distance to one electrode (compared to the appropriate temperature region 16). Then, since the resistance value of the path passing through the low temperature region 17 becomes large (compared to the appropriate temperature region 16), the influence on the interelectrode resistance value when the resistance value of the low temperature region 17 changes is small. That is, the change in the output of the detection unit (change in the resistance value between the electrodes) when the detection target gas comes into contact with the low temperature portion 17 of the gas sensor 50 is smaller than that in the appropriate temperature portion 16.

  In the fourth embodiment, as shown in FIG. 10, of the comb-like electrodes of the pair of electrodes 41 and 42, the electrode extending along the outer periphery of the substrate 10 is about half of the first embodiment. It is formed in length. Specifically, since the tip portion 411 of the comb-like electrode of the electrode 41 is formed shorter than the other comb-like electrodes of the electrode 41, the electrode 41 is not attached to the low temperature portion 17 located at the lower right in the top view. Not placed. Similarly, the tip portion 421 of the comb-like electrode of the electrode 42 is formed shorter than the other comb-like electrodes of the electrode 42, so that the electrode 42 is disposed in the low temperature portion 17 located on the upper left in the top view. It has not been.

  The above-described detection temperature is determined according to the material used as the gas sensitive body 50, and is set in the range of 350 ° C to 550 ° C. For example, when detecting methane gas using tin oxide for the gas sensitive body 50, it is appropriate that the detection temperature is 400 ° C to 500 ° C.

  In the fourth embodiment, the measurement contribution portion 18, which is a portion where the sum of the distance from the one electrode 41 and the distance from the other electrode 42 is equal to or less than a predetermined measurement contribution distance, is low in the plan view of the substrate 10. It does not overlap with the part 17. The measurement contributing portion 18 is indicated by the hatched portion in FIG.

  The measurement contribution portion 18 is a portion on the substrate where the sum of the distance from one electrode 41 and the distance from the other electrode 42 is equal to or less than a predetermined measurement contribution distance, and the shape and arrangement of the pair of electrodes 41, 42. It is a site determined by. As described above, since the inter-electrode resistance value R, that is, the degree of influence on the detection result of the detection unit 40, changes according to the distance from the electrode, the gas sensitive body 50 located in the measurement contributing part 18 is placed in other parts. The contribution to the detection result of the detection unit 40 is greater than that of the gas sensitive body 50 positioned.

  That is, since the measurement contributing portion 18 is not provided overlapping the low temperature portion 17 in plan view, the influence of the low temperature portion 17 of the gas sensitive body 50 on the detection result of the detection unit 40 can be reduced. Therefore, even if the sensitivity change due to humidity or a long-term sensitivity decrease occurs in the low temperature portion 17, the influence on the output of the semiconductor gas sensor 1a can be reduced, and the short-term humidity dependency and the long-term sensitivity decrease can be reduced. The suppressed semiconductor gas sensor 1a can be realized.

<Fifth Embodiment>
In the first to fourth embodiments, the gas sensitive body non-covered region 15 that is not covered with the gas sensitive body 50 is formed at the second connecting end portion 14 where the temperature is lowered by the connection with the second bridging portion 22. Thus, the temperature of the gas sensitive body 50 that is low in temperature is reduced (less), and short-term humidity dependence and long-term sensitivity reduction are suppressed.

  In the semiconductor gas sensor 1a (gas sensor 1) according to the fifth embodiment, as shown in FIGS. 12 and 13, the center point 61 that is the center in the top view of the substrate 10, the substrate 10, the second bridging portion 22, and Among the regions in the substrate 10 separated by the vertical bisector connecting the connecting point 62, the second region 63 that is the region on the connecting point 62 side is not covered with the gas sensitive body 50. The gas sensitive body non-coating region 15, that is, the alumina 51 is formed.

  Hereinafter, the semiconductor gas sensor 1a according to the fifth embodiment will be described with reference to FIGS. 12 is a top view of the substrate 10 of the semiconductor gas sensor 1a, and FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. In addition, description is abbreviate | omitted about the structure which is common in 1st Embodiment.

  A center point 61 shown in FIG. 12 is a central point in the top view of the substrate 10, that is, an intersection of diagonal lines of the rectangular substrate 10. Note that the center of the circle may be the center point 61 when the substrate 10 is circular, and the geometric center of gravity may be the center point 61 in other shapes.

  The connection point 62 is a point where the substrate 10 and the second bridging portion 22 are connected, and is the upper left and lower right vertices of the substrate 10 shown in plan view in FIG. The connection point 62 may be a vertex of the substrate 10 that is square in a top view, or may be one point of a portion of the side of the substrate 10 that is in contact with the second bridging portion 22 in a top view. Further, when the substrate 10 is circular, it may be one point of the outer periphery of the substrate 10 that is in contact with the second bridging portion 22 in top view.

  As shown in FIG. 12, the perpendicular bisector connecting the center point 61 and the connection point 62 intersects with two sides of the substrate 10 that is square in a top view, and divides the substrate 10. Alumina 51 is coated on the second region 63, which is the region on the connection point 62 side, of the divided regions. That is, the gas sensitive body non-covering region 15 is formed in the second region 63.

  Since the power supply line 23 for supplying power to the heater 30 is not provided in the second bridging portion 22, heat flows out through the second bridging portion 22 in the vicinity of the connection point 62 between the substrate 10 and the second bridging portion 22. As a result, the temperature decreases. That is, in the second region 63, the temperature of the substrate 10 is lower than that near the center of the substrate 10. Therefore, by forming the gas sensitive body non-covering region 15 in the second region 63, the gas sensitive body 50 having a low temperature is made small (less), and the short-term humidity dependence and long-term sensitivity reduction of the gas sensor 1 are reduced. Can be suppressed.

<Modification of Fifth Embodiment>
14 and 15 show a modification of the fifth embodiment. In this modification, the gas sensitive body non-covered region 15, that is, the alumina 51 is provided in the second region 63, and the gas sensitive member 50 is provided in the vicinity of the connection point 62 inside the second region 63. As described above, even when the gas sensitive body 50 is not partially covered by the gas sensitive body uncovered area 15 and the gas sensitive body 50 is partially present, the entire surface of the substrate 10 is covered with the gas sensitive body 50. In comparison, since the gas sensitive body 50 having a low temperature can be made small (less), the short-term humidity dependence and long-term sensitivity deterioration of the gas sensor 1 can be suppressed.

<Sixth Embodiment>
A gas detector can be configured using the gas sensor 1 described above and an output unit that outputs gas information related to the detection target gas based on the output of the gas sensor 1.
The gas sensor 1 has the gas sensor 1 in which the gas sensitive body non-covering region 15 is formed at the second connection end portion 14 of the substrate 10, so that the short-term humidity dependency and the long-term sensitivity decrease are suppressed. . If a gas detector is configured by combining this with an output unit that outputs gas information related to the detection target gas based on the output of the gas sensor 1, short-term humidity dependence and long-term sensitivity deterioration are suppressed, and reliability is improved. A highly reliable gas detector can be realized.

  The output unit converts the output of the gas sensor 1 into a gas concentration. Specifically, a resistance value, which is an output value from the detection unit 40 of the gas sensor 1, is converted into digital data using a Wheatstone bridge circuit and an A / D converter, and converted into a gas concentration based on the sensitivity characteristics of the gas sensor 1. .

  The output unit further compares the obtained gas concentration with a preset threshold value, and outputs an alarm (gas information) indicating that the detection target gas has been detected when the gas concentration exceeds the threshold value. The alarm as the gas information may be simply information on the presence or absence of the detection target gas, or may include information on the gas concentration. The alarm may emit sound or light, or may notify other devices.

<Another embodiment>
(1) In each of the embodiments described above, the substrate 10 is supported by two first bridging portions 21 and two second bridging portions 22, that is, four bridging portions, but the number of bridging portions is five or more. However, it may be three or two. In the case where there are two bridging portions, the power supply line 23 is provided in one first bridging portion 21, and the gas sensor uncovered region 15 is provided in the second connection end portion 14 where one second bridging portion is connected to the substrate 10. Provided.

  (2) In the above-described embodiments, the two first bridging portions 21 are connected to the diagonal corners of the substrate 10, and the two second bridging portions 22 are connected to the remaining corners of the substrate 10. The two first bridging portions 21 may be connected to adjacent corners of the substrate 10, and the two second bridging portions 22 may be connected to the remaining adjacent corners of the substrate 10.

  (3) In the first to fourth embodiments, the second bridging portion 22 is connected to the apex of the substrate 10 that is square in a top view, and a sector having a predetermined radius with the point (the apex of the substrate 10) as the apex. A gas-sensitive body non-covering region 15 is formed in this region. As in the modification of the fifth embodiment shown in FIG. 14, the gas sensitive body 50 is formed in the vicinity of the apex (connection point 62) of the substrate 10 and the gas sensitive body non-covered region 15 ( Alumina 51) may also be provided. Even in such a form, it can be said that the gas sensitive body non-covering region 15 is formed in the second connection end portion 14, and the heat from the second bridging portion 22 is reduced by reducing the temperature of the gas sensitive body 50 that becomes low temperature. The gas sensor 1 in which the short-term humidity dependency and the long-term sensitivity decrease are suppressed can be realized by reducing the influence of the outflow.

<Results of short-term and long-term humidity effects>
Hereinafter, the test results of the short-term humidity effect and the long-term humidity effect for Example 1 and Comparative Example 1 according to the first embodiment are shown. Next, test results of long-term humidity effects for Example 2 and Comparative Example 2 according to the third embodiment are shown.

<Example 1: First Embodiment>
Using silicon for the support substrate 2, the base 11, the first bridge portion 21, the second bridge portion 22, and the insulating layer 12 are formed of SiO ₂ , and the heater 30 and the electrodes 41 and 42 are formed of platinum, A test sample of Example 1 according to the first embodiment described above was created using tin oxide as the gas sensitive body 50. Alumina is disposed in the gas-sensitive body uncoated region 15.

<Comparative Example 1>
As a test sample of Comparative Example 1, as shown in FIG. 16 , a test sample having a form in which the entire surface of the substrate 10 was covered with the gas sensitive body 50 was prepared. As the gas sensitive member 50, tin oxide was used as in Example 1. Other configurations were the same as those in Example 1.

<Short-term humidity effect>
The test sample was placed in an environment with a relative humidity of 5%, 65%, and 90%, and a resistance value Ra in air and a resistance value Rm at 3000 ppm of methane were measured. The dependency of methane (3000 ppm) sensitivity S (hereinafter abbreviated as “sensitivity S”; sensitivity S = Ra / Rm) on relative humidity was compared between Example 1 and Comparative Example 1. The comparison results are shown in FIG.

  In Comparative Example 1, the sensitivity S is as high as 59 at a relative humidity of 5%, but the sensitivity S decreases rapidly to 12 at a relative humidity of 65%, and further decreases to 12 at a relative humidity of 90%. It was.

  On the other hand, in Example 1, the sensitivity S was 43 at a relative humidity of 5%, which was lower than that of Comparative Example 1. However, the sensitivity S was 25 at a relative humidity of 65%, and the sensitivity S was 20 at a relative humidity of 95%, which was higher than that of Comparative Example 1. In addition, the amount of decrease in sensitivity at high humidity based on the sensitivity of 5% relative humidity was smaller in Example 1 than in Comparative Example 1. That is, in Example 1, the short-term humidity dependency is suppressed to be smaller than that in Comparative Example 1.

<Long-term humidity effect>
The test sample was placed in an environment of a temperature of 50 ° C. and a relative humidity of 90% for 45 days, and the resistance value Ra in air and the resistance value Rm at 3000 ppm of methane were measured to calculate the sensitivity S. FIG. 18 shows the rate of change from the initial value, with the sensitivity S at the start of measurement as the initial value.

  Also, the concentration of methane gas (alarm concentration) that gives an alarm as a gas alarm when the sensor output exceeds the threshold was measured. The transition of alarm concentration is shown in FIG.

  In Comparative Example 1, the sensitivity S decreased as the number of test days elapsed, and decreased to 0.6 times the sensitivity at the start of the test after 45 days from the start of the test. The alarm concentration increases as the number of test days elapses. At the start of the test, the alarm was issued when the methane gas concentration was 3000 ppm, but when the methane gas concentration did not increase to 5400 ppm after 45 days, no alarm was issued. It became.

  On the other hand, in Example 1, the sensitivity S did not greatly decrease even when the test days passed, and the sensitivity at the start of the test was kept almost the same even after 45 days from the start of the test. Further, no significant increase was observed in the alarm concentration, and even after 45 days from the start of the test, an alarm was issued at a methane gas concentration of 3000 ppm. That is, in Example 1, a long-term decrease in sensitivity is suppressed as compared with Comparative Example 1.

<Example 2: Third embodiment>
The base 11, the first bridging portion 21, and the second bridging portion 22 are formed of SiO ₂ using silicon for the support substrate 2, the resistor 43 is formed of platinum, and palladium is supported as the gas sensitive body 50. The test sample of Example 2 which concerns on the above-mentioned 3rd Embodiment was created using the alumina. Alumina is disposed in the gas-sensitive body uncoated region 15.

<Comparative Example 2>
As a test sample of Comparative Example 2, as shown in FIG. 20, a test sample having a form in which the entire surface of the substrate 10 was covered with the gas sensitive body 50 was prepared. As the gas sensitive body 50, the alumina supported by palladium was used as in the first embodiment. Other configurations were the same as those in Example 2.

<Long-term humidity effect>
Similar to Example 1 and Comparative Example 1 described above, the test sample was placed in an environment of a temperature of 50 ° C. and a relative humidity of 90% for 45 days, and a test for measuring sensitivity S and alarm concentration was performed. FIG. 21 shows the rate of change of the sensitivity S from the initial value, and FIG. 22 shows the transition of the alarm concentration.

  In Comparative Example 2, the sensitivity S decreased as the number of test days passed, and decreased to 0.7 times the sensitivity at the start of the test after 45 days from the start of the test. The alarm concentration increases as the number of test days elapses. At the start of the test, the alarm was issued when the methane gas concentration was 3000 ppm, but when the methane gas concentration did not increase to 4500 ppm after 45 days, no alarm was issued. It became.

  On the other hand, in Example 2, the sensitivity S gradually decreased as the number of test days passed. However, even after 45 days from the start of the test, the sensitivity at the start of the test and 0.95 times the sensitivity were maintained. Further, no significant increase was observed in the alarm concentration, and even after 45 days from the start of the test, an alarm was issued at a methane gas concentration of 3000 ppm. That is, in Example 2, the long-term sensitivity decrease is suppressed as compared with Comparative Example 2.

  Note that the configurations disclosed in the above-described embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with the configurations disclosed in the other embodiments as long as no contradiction arises. The embodiment disclosed in this specification is an exemplification, and the embodiment of the present invention is not limited to this. The embodiment can be appropriately modified without departing from the object of the present invention.

  It can be effectively used as a gas sensor in which short-term humidity dependence and long-term sensitivity deterioration are suppressed.

1: Gas sensor 1a: Semiconductor gas sensor 2: Support substrate 3: Cavity 10: Substrate 11: Base 12: Insulating layer 13: First connection end 14: Second connection end 15: Gas-sensitive body non-covering region 16: Suitable temperature part 17: Low temperature part 18: Measurement contributing part 21: First bridge part 22: Second bridge part 23: Feed line 24: Detection line 25: Feed detection line (feed line)
30: Heater (heating unit)
40: Detection unit 41: Electrode 42: Electrode 43: Resistor (detection unit)
50: Gas sensitive body 51: Alumina 60: Second region 61: Center point 62: Connection point T: Masking tape

Claims (24)

A gas sensor having a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected has contacted the gas sensitive body, and a heating unit that heats the gas sensitive body,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
Of the connection end portions of the substrate, the second connection end portion to which the second bridging portion is connected is formed with a gas-sensitive body uncovered region that is not covered with the gas sensitive body ,
A gas sensor in which the gas sensitive body is coated on a first connection end portion to which the first bridging portion is connected among the connection end portions of the substrate . A gas sensor having a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected has contacted the gas sensitive body, and a heating unit that heats the gas sensitive body,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
Of the regions in the substrate that are separated by a vertical bisector connecting a center point that is the center of the substrate in a top view and a connection point between the substrate and the second bridging portion, the connection In the second region, which is a region on the point side, a gas-sensitive body non-covering region that is not covered by the gas-sensitive body is formed,
A gas sensor in which the gas sensitive body is coated on a first connection end portion to which the first bridging portion is connected among the connection end portions of the substrate. A gas sensor having a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected has contacted the gas sensitive body, and a heating unit that heats the gas sensitive body,
An insulating layer is provided so as to cover the heating unit provided on the base constituting the substrate;
A pair of electrodes is provided on the insulating layer;
The gas sensitive body is provided on the insulating layer and the pair of electrodes,
The detection unit includes the pair of electrodes, and is configured to detect the detection target gas based on a change in resistance value between the pair of electrodes.
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
A gas sensor in which a gas-sensitive body non-covering region that is not covered with the gas-sensitive body is formed in a second connection end portion to which the second bridging portion is connected among the connection end portions of the substrate. A gas sensor having a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected has contacted the gas sensitive body, and a heating unit that heats the gas sensitive body,
A resistor having a function as the detection unit and a function as the heating unit is provided on the base constituting the substrate,
The gas sensitive body is provided on the resistor and the base,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion has a first bridging portion provided with a feed line that feeds power to the resistor as the heating portion, and a second bridging portion not provided with the feed line,
A gas sensor in which a gas-sensitive body non-covering region that is not covered with the gas-sensitive body is formed in a second connection end portion to which the second bridging portion is connected among the connection end portions of the substrate. A gas sensor having a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected has contacted the gas sensitive body, and a heating unit that heats the gas sensitive body,
An insulating layer is provided so as to cover the heating unit provided on the base constituting the substrate;
A pair of electrodes is provided on the insulating layer;
The gas sensitive body is provided on the insulating layer and the pair of electrodes,
The detection unit includes the pair of electrodes, and is configured to detect the detection target gas based on a change in resistance value between the pair of electrodes.
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
Of the regions in the substrate that are separated by a vertical bisector connecting a center point that is the center of the substrate in a top view and a connection point between the substrate and the second bridging portion, the connection A gas sensor in which a gas-sensitive body non-covering area that is not covered with the gas-sensitive body is formed in a second area that is an area on the point side. A gas sensor having a gas sensitive body provided on a substrate, a detection unit that detects that a gas to be detected has contacted the gas sensitive body, and a heating unit that heats the gas sensitive body,
A resistor having a function as the detection unit and a function as the heating unit is provided on the base constituting the substrate,
The gas sensitive body is provided on the resistor and the base,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion has a first bridging portion provided with a feed line that feeds power to the resistor as the heating portion, and a second bridging portion not provided with the feed line,
Of the regions in the substrate that are separated by a vertical bisector connecting a center point that is the center of the substrate in a top view and a connection point between the substrate and the second bridging portion, the connection A gas sensor in which a gas-sensitive body non-covering area that is not covered with the gas-sensitive body is formed in a second area that is an area on the point side. 7. The gas sensitive body according to claim 3, wherein the gas sensitive body is coated on a first connection end portion to which the first bridging portion is connected among the connection end portions of the substrate. Gas sensor. In the gas non-sensitive body non-covering region, a gas low-sensitive body whose sensitivity to the detection target gas is smaller than that of the gas sensitive body or a gas non-sensitive body which does not have sensitivity to the detection target gas is formed by coating. The gas sensor according to any one of claims 1, 2, 3, and 5. The gas sensor according to any one of claims 1, 2, 3, 5, and 8, wherein the gas sensitive body non-covering region is coated with a high resistance body having a larger electric resistance than the gas sensitive body. The gas sensor according to claim 9, wherein the high resistance body includes an insulating oxide as a main component. The gas sensor according to any one of claims 1, 2, 3, 5, 8 to 10, wherein the gas sensitive body includes an oxide semiconductor as a main component. The gas sensitive body has catalytic activity for promoting the combustion of the gas to be detected in contact with the gas, and the gas at the second connection end to which the second bridging portion is connected among the connection ends of the substrate. The catalyst uncoated region is coated with a catalyst low-activity having a catalytic activity lower than that of the gas-sensitive material or a catalyst inert having no catalytic activity. The gas sensor according to any one of claims. The gas sensor according to claim 12, wherein the catalyst low-activity or the catalyst deactivation is mainly composed of a metal oxide. The gas sensor according to claim 12 or 13, wherein the gas sensitive body contains a noble metal catalyst supported on a metal oxide. The gas sensor according to any one of claims 1 to 14, wherein the heating unit heats the gas sensitive body to a predetermined detection temperature or higher during measurement, and the detection temperature is 350 ° C or higher and 550 ° C or lower. A gas detector comprising: the gas sensor according to claim 1; and an output unit that outputs gas information related to the detection target gas based on an output of the gas sensor. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
A gas sensitive body non-covering region that is not covered with the gas sensitive body is formed in a second connecting end portion to which the second bridging portion is connected among the connecting end portions of the substrate, and the connecting end portion of the substrate is formed. A method of manufacturing a gas sensor, comprising: an attaching step of attaching the material of the gas sensitive body onto the substrate in a form in which the gas sensitive body is formed at a first connection end portion to which the first bridging portion is connected. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
On the second connection end portion to which the second bridging portion is connected among the connection end portions, a gas low-sensitivity body whose sensitivity to the detection target gas is smaller than the gas sensitivity body, or the detection target gas. A first attachment step of attaching a gas insensitive body having no sensitivity;
A gas sensor manufacturing method comprising: a second adhesion step of depositing a material of the gas sensitive body on the substrate including a first connection end portion to which the first bridging portion is connected among the connection end portions. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
On the second connection end portion to which the second bridging portion is connected among the connection end portions, a catalyst low activity body that has a catalytic activity that promotes combustion of the gas to be detected that is in contact with the gas detection body is lower, Or a first attachment step of attaching a catalyst inert that does not have catalytic activity to promote combustion of the gas to be detected that has come into contact;
A gas sensor manufacturing method comprising: a second adhesion step of depositing a material of the gas sensitive body on the substrate including a first connection end portion to which the first bridging portion is connected among the connection end portions. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
A masking step of covering the second connection end to which the second bridging portion is connected among the connection ends with a masking material;
An adhesion step of depositing the gas sensitive material on the substrate after the masking step;
And a step of removing the masking material after the attaching step. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
Forming the heating unit on a base constituting the substrate;
Forming an insulating layer so as to cover the heating unit;
Forming a pair of electrodes on the insulating layer;
In the form of forming a gas-sensitive body non-covering region that is not covered with the gas sensitive body at a second connecting end to which the second bridging portion is connected among the connecting end portions of the substrate, An adhesion step of depositing material on the insulating layer and the pair of electrodes;
The said detection part has a pair of said electrode, The manufacturing method of the gas sensor comprised so that the said detection object gas may be detected based on the change of the resistance value between the said pair of electrodes. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
Forming a resistor having a function as the detection unit and a function as the heating unit on a base constituting the substrate;
In the form of forming a gas-sensitive body non-covering region that is not covered with the gas sensitive body at a second connecting end to which the second bridging portion is connected among the connecting end portions of the substrate, A method for manufacturing a gas sensor, comprising: an attaching step of attaching a material onto the resistor and the base. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
Forming the heating unit on a base constituting the substrate;
Forming an insulating layer so as to cover the heating unit;
Forming a pair of electrodes on the insulating layer;
On the second connection end portion to which the second bridging portion is connected among the connection end portions, a gas low-sensitivity body whose sensitivity to the detection target gas is smaller than the gas sensitivity body, or the detection target gas. A first attachment step of attaching a gas insensitive body having no sensitivity;
A second deposition step of depositing the material of the gas sensitive body on the insulating layer and the pair of electrodes;
The said detection part has a pair of said electrode, The manufacturing method of the gas sensor comprised so that the said detection object gas may be detected based on the change of the resistance value between the said pair of electrodes. A gas sensor manufacturing method comprising: a gas sensor provided on a substrate; a detection unit that detects that a detection target gas has contacted the gas sensor; and a heating unit that heats the gas sensor,
The substrate is supported on a support substrate by a bridging portion connected to a connection end of the substrate,
The bridging portion includes a first bridging portion provided with a feeding line for feeding power to the heating portion, and a second bridging portion not provided with the feeding line,
Forming a resistor having a function as the detection unit and a function as the heating unit on a base constituting the substrate;
On the second connection end portion to which the second bridging portion is connected among the connection end portions, a catalyst low activity body that has a catalytic activity that promotes combustion of the gas to be detected that is in contact with the gas detection body is lower, Or a first attachment step of attaching a catalyst inert that does not have catalytic activity to promote combustion of the gas to be detected that has come into contact;
A gas sensor manufacturing method comprising: a second attachment step of attaching a material of the gas sensitive body onto the resistor and the base.

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