A MEMS thermal pile array chip and a multi-component gas detection device

Abstract

The application relates to a MEMS thermal pile array chip and a multi-component gas detection device, which comprises a silicon substrate, a plurality of thermal pile unit groups are arranged in an array on the silicon substrate, each thermal pile unit group comprises a reference thermal pile and a test thermal pile, the reference thermal pile and the test thermal pile each comprise a heat insulation cavity, three layers of support films, a plurality of polycrystalline silicon thermocouple pairs, a ring-shaped heater, a heat-distributing metal, a heating electrode and an output electrode; the three layers of support films are arranged on the heat insulation cavity; the plurality of polycrystalline silicon thermocouple pairs are connected in series with each other and are wrapped between the lower two layers of support films; the ring-shaped heater is wrapped between the upper two layers of support films; the heat-distributing metal is wrapped between the upper two layers of support films and is located in the middle of the ring-shaped heater; and the test thermal pile further comprises a catalyst, the catalyst is located on the surface of the uppermost layer of support films and covers the heat-distributing metal. The MEMS thermal pile array chip has the characteristics of low detection lower limit, wide linear range and short response recovery time, and can detect the concentration of multi-component gases.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of microchips and intelligent sensors, and particularly relates to a MEMS thermal pile array chip and a multi-component gas detection device. BACKGROUND

[0002] Combustible gas detection has a wide range of applications in the fields of industry, new energy, nuclear power, lithium battery hydrogen energy vehicles, etc. For example, natural gas, liquefied petroleum gas, etc. are important fuels, which are used in the fields of industrial boilers, power generation, etc. In the chemical industry, combustible gases such as hydrogen and methane are important raw materials for the synthesis of ammonia, methanol and other chemicals, and are also key components in the cracking and reforming processes in the petrochemical industry. More importantly, as the impact of global warming on the climate becomes more and more significant, countries around the world are actively transforming their energy structures and setting carbon neutralization targets. Hydrogen, as an important clean energy in the future, can be used as a fuel cell to generate electricity and applied to the fields of automobiles, trains, ships and aviation.

[0003] In many scenarios, combustible gases do not simply appear as single-component gases, but two or more combustible gases appear at the same time. For example, a certain proportion of hydrogen is mixed into natural gas to form hydrogen-doped methane, which is used in daily life and industrial production. Hydrogen-doped methane can not only improve the combustion efficiency of natural gas and reduce carbon emissions, but also can use existing natural gas pipelines and other infrastructure to transport and use hydrogen, greatly reducing the use cost of hydrogen energy, and is gradually being promoted in countries around the world. In a transformer substation, the insulation between the coils weakens as the service life increases, resulting in the generation of electric arcs under high voltage, which eventually causes the sealed oil to release a variety of combustible gases such as hydrogen, methane and acetylene. Since combustible gases are flammable and explosive, they can leak during pipeline transportation and storage, or be generated when the transformer fails, which can easily cause combustion and explosion, resulting in personal injury and economic loss. Therefore, it is necessary to quickly and real-time detect trace amounts of combustible gases.

[0004] Currently, the types of combustible gas sensors mainly include electrochemical, semiconductor and catalytic combustion types. Electrochemical and semiconductor sensors use the adsorption and diffusion process of gas molecules, and their concentration detection has a limited linear range (usually the concentration detection range spans ~1-2 orders of magnitude), slow response and recovery speed (tens to hundreds of seconds), which is not conducive to fast and real-time detection scenarios. Catalytic combustion type sensors (such as ceramic tube structures) have the problems of large size, high operating temperature (such as 560℃ for hydrogen), high power consumption (hundreds of milliwatts) and low detection limit.

[0005] More importantly, the above-mentioned sensors usually only detect a single component of gas. The scene of flammable gas mixture increases the complexity of gas detection, which puts higher requirements on the sensor chip and detection device, and needs to have high sensitivity, fast response, low power consumption and multi-component detection capability. SUMMARY

[0006] The main purpose of the present application is to provide a MEMS thermal pile array chip and a multi-component gas detection device, which can effectively solve the problems in the background art.

[0007] To achieve the above purpose, the present application is realized by the following technical scheme:

[0008] A MEMS thermal pile array chip, comprising a silicon substrate, a plurality of thermal pile unit groups are arranged in an array on the silicon substrate, each thermal pile unit group comprises a reference thermal pile and a test thermal pile, the reference thermal pile and the test thermal pile each comprise

[0009] A heat insulation cavity is opened on the upper surface of the silicon substrate;

[0010] Three layers of supporting films are arranged on the heat insulation cavity;

[0011] A plurality of polysilicon thermocouple pairs are connected in series and wrapped between the lower two layers of supporting films, and a plurality of the polysilicon thermocouple pairs are arranged in a central symmetry, with their hot ends located in the central region of the supporting film and their cold ends located in the edge region of the supporting film;

[0012] A ring-shaped heater is wrapped between the upper two layers of supporting films and located above the hot ends of the plurality of polysilicon thermocouple pairs;

[0013] A heat uniformizing metal is wrapped between the upper two layers of supporting films and located in the middle of the ring-shaped heater;

[0014] A heating electrode is arranged on the silicon substrate and electrically connected to the ring-shaped heater;

[0015] An output electrode is arranged on the silicon substrate and electrically connected to the plurality of polysilicon thermocouple pairs;

[0016] The test thermal pile further comprises a catalyst, which is located on the surface of the uppermost layer of supporting film and covers the heat uniformizing metal.

[0017] Preferably, the heat uniformizing metal is ring-shaped and made of metal Mo.

[0018] Preferably, the material of the supporting film is silicon nitride.

[0019] Preferably, the polysilicon thermocouple pair is in a straight line structure.

[0020] A multi-component gas detection device comprises the MEMS thermal pile array chip, and further comprises

[0021] A shell having a display screen on the shell;

[0022] A test circuit mounted in the shell and electrically connected to the display screen;

[0023] A PCB board plugged on the test circuit, the PCB board having a test cavity, and the MEMS thermal pile array chip being mounted in the test cavity;

[0024] A battery mounted in the shell for powering the test circuit.

[0025] The present application provides a MEMS thermal pile array chip and a multi-component gas detection device, which has the following advantages:

[0026] 1. The MEMS thermal pile array chip detects the concentration of target combustible gas molecules through the difference between the test thermal pile output voltage and the reference thermal pile output voltage, has a low detection lower limit (0.5-1 ppm), a wide linear range (across 4 orders of magnitude), a short response recovery time (<1 second), and the like, has superior and comprehensive performance compared with existing sensors, and can detect multi-component gas concentration, and has a good application prospect.

[0027] 2. In the present application, the support film is a three-layer structure, and a plurality of polysilicon thermocouple pairs are wrapped between the two layers of support films. The three-layer support film and the polysilicon thermocouple pairs can be obtained by chemical vapor deposition, so that the thickness of the polysilicon thermocouple pairs and the support film is thinner, the heat capacity of the support film is smaller, the heating speed of the support film after the catalytic reaction is faster, the response time of the device is shorter, and the heat release for lower concentration gas is more sensitive. At the same time, the thinner support film makes the temperature rise more when absorbing the same heat, and the heat release for lower concentration gas is more sensitive. When reaching the same temperature, the required heating power is lower.

[0028] 3. By arranging the heat-uniformizing metal, the temperature uniformity of the central heating area of the support film is improved. When the heat-uniformizing metal exists, the temperature deviation of the heating area of the device is only 1%, which is obviously superior to the device without the heat-uniformizing metal. The better temperature uniformity can heat the catalyst more uniformly, thereby improving the signal strength and realizing the detection of lower concentration gas. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of the MEMS thermal pile array chip of the present application;

[0030] Figure 2 It is a structural schematic diagram of a single reference thermal pile and a test thermal pile of the present application;

[0031] Figure 3 Structure diagram of three-layer support film and polycrystalline silicon thermocouple pair of the present application;

[0032] Figure 4 Structure diagram of two thermal pile units of the second embodiment of the present application;

[0033] Figure 5 Response recovery curve diagram of H2 and CH4 of the second embodiment of the present application;

[0034] Figure 6 Test effect diagram of different concentrations of H2 and CH4 and corresponding differential signals of the second embodiment of the present application;

[0035] Figure 7 Detection concentration result diagram of H2 and CH4 mixed gas of the second embodiment of the present application;

[0036] Figure 8 Temperature uniformity test diagram of the central heating area of the support film in the case of the present application with heat-uniform metal;

[0037] Figure 9 Temperature uniformity test diagram of the central heating area of the support film in the case of the present application without heat-uniform metal;

[0038] Figure 10 Exploded view of the multi-component gas detection device of the present application;

[0039] Figure 11 Schematic diagram of the test circuit of the present application.

[0040] In the figure: 100, silicon substrate; 1, reference thermopile; 2, test thermopile; 10, heat insulation cavity; 20, support film; 30, polycrystalline silicon thermocouple pair; 40, ring heater; 50, heat-uniform metal; 60, heating electrode; 70, output electrode; 80, catalyst; 101, MEMS thermopile array chip; 102, shell; 103, test circuit; 104, PCB board; 105, battery; 106, display screen. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below in combination with the drawings of the present application.

[0042] The technical solutions of the present application will be described clearly and completely below in combination with embodiments. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0043] In the description of the present application, it needs to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the devices or elements indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0044] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can include one or more of the features explicitly or implicitly. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited. In addition, the terms "mounting", "connecting", "connecting" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0045] Embodiment one

[0046] Referring to Figures 1-3 A MEMS thermal pile array chip 101, comprising a silicon substrate 100, a plurality of thermal pile unit groups are arranged in an array on the silicon substrate 100, the thermal pile unit groups comprise a reference thermal pile 1 and a test thermal pile 2, the reference thermal pile 1 and the test thermal pile 2 each comprise

[0047] A heat insulation cavity 10 is opened on the upper surface of the silicon substrate 100;

[0048] A three-layer support film 20 is arranged on the heat insulation cavity 10;

[0049] A plurality of polysilicon thermocouple pairs 30 are connected in series with each other and wrapped between the lower two layers of support films 20, a plurality of the polysilicon thermocouple pairs 30 are arranged in a central symmetry, the hot end of which is located in the central region of the support film 20, and the cold end of which is located in the edge region of the support film 20;

[0050] A ring-shaped heater 40 is wrapped between the upper two layers of support films 20 and located above the hot end of the plurality of polysilicon thermocouple pairs 30;

[0051] The uniform heat metal 50 is wrapped between the two layers of support films 20 and located in the middle of the annular heater 40;

[0052] The heating electrode 60 is arranged on the silicon substrate 100 and electrically connected with the annular heater 40.

[0053] The output electrode 70 is arranged on the silicon substrate 100 and electrically connected with the plurality of polycrystalline silicon thermocouple pairs 30.

[0054] The test thermopile 2 further comprises a catalyst 80 located on the surface of the uppermost support film 20 and covering the uniform heat metal 50.

[0055] In the embodiment, the uniform heat metal 50 is annular and made of metal Mo, and the support film 20 is made of silicon nitride, and the polycrystalline silicon thermocouple pair 30 is in a linear structure.

[0056] In the embodiment, the heat insulation cavity 10 is obtained by deep reactive ion etching on the silicon substrate 100, the three layers of support films 20 and the polycrystalline silicon thermocouple pairs 30 are obtained by chemical vapor deposition, the support film 20 can suspend the polycrystalline silicon thermocouple pair 30, the annular heater 40 and the uniform heat metal 50 above the heat insulation cavity 10, thereby reducing the heat loss of the reference thermopile 1 and the test thermopile 2 and ensuring the accuracy of the detection result, the diameter of the support film 20 is 600 μm, the polycrystalline silicon thermocouple pair 30 is 8 pairs, and the annular heater 40 and the uniform heat metal 50 are obtained by magnetron sputtering, and the diameter surrounded by the annular heater 40 is 250 μm.

[0057] The polycrystalline silicon thermocouple pair 30 comprises an N-type polycrystalline silicon thermocouple and a P-type polycrystalline silicon thermocouple, the N-type polycrystalline silicon thermocouple and the P-type polycrystalline silicon thermocouple are connected in series through a metal interconnection structure, and a plurality of the polycrystalline silicon thermocouple pairs are also connected in series through the metal interconnection structure. When a plurality of thermocouples are connected in series, the thermoelectric power is U=N(αA-αB)ΔT, where αA and αB are the Seebeck coefficients of the p-type and n-type doped polycrystalline silicon, and N is the number of thermocouples.

[0058] In the present application, one thermopile unit group comprises a reference thermopile 1 and a test thermopile 2, the surface of the uppermost support film 20 of the reference thermopile 1 is not loaded with the catalyst 80, and the surface of the uppermost support film 20 of the test thermopile 2 is loaded with a specific catalyst 80, which can catalyze the oxidation reaction of the target combustible gas molecules and oxygen in the air to release heat at the optimal catalytic temperature.

[0059] Specifically, in use, the MEMS thermopile array chip 101 applies a heating voltage (V H), the temperature of the reference heat pile 1 and the test heat pile 2 is controlled to reach the optimum catalytic temperature of the catalyst 80 after the heat of the annular heater 40 is released, wherein the heat of the annular heater 40 is transmitted to the catalyst 80 through the uniform metal 50 and the supporting film 20.

[0060] The hot end of the polysilicon thermocouple pair 30 is located at the central region of the supporting film 20, and the temperature of the reference heat pile 1 and the test heat pile 2 is controlled to reach the optimum catalytic temperature of the catalyst 80 after the heat of the annular heater 40 is released, wherein the heat of the annular heater 40 is transmitted to the catalyst 80 through the uniform metal 50 and the supporting film 20. r ), the test heat pile 2 output voltage (Vs) and the reference heat pile 1 output voltage (Vr) are differentiated, and the concentration of the target combustible gas molecules is detected through the differential signal AV (AV = Vs-Vr).

[0061] More specifically, when the target combustible gas molecules with extremely low concentration (ppm level) exist in the detection environment, the target combustible gas molecules and the oxygen in the air are oxidized to release heat under the catalysis of the catalyst 80, and the polysilicon thermocouple of the test heat pile 2 absorbs the reaction heat to increase the temperature, and the differential signal AV (AV = Vs-Vr) reflects the catalytic oxidation exothermic process of the target combustible gas molecules in the detection environment, and the output signal strength is proportional to the concentration of the target combustible gas molecules in the detection environment.

[0062] Example Two

[0063] The silicon substrate 100 is provided with a plurality of heat pile unit groups, and the heat pile unit group includes a reference heat pile and a test heat pile, and the multi-component gas concentration detection can be performed, which is further described below in combination with specific examples.

[0064] Reference Figure 4Taking a monolithically integrated 4-channel thermal stack array chip as an example, there are two thermal stack unit groups, group a and group b, which include reference thermal stack a and test thermal stack a, as well as reference thermal stack b and test thermal stack b. These are used to detect and verify the concentration of a two-component mixture of hydrogen (H2) and methane (CH4). The chip size is 2mm × 2mm. Test thermal stack a and test thermal stack b are each loaded with a noble metal catalyst. Platinum nanoparticle / alumina (Pt / Al2O3) catalyst is loaded on test thermal stack a. Pt nanoparticles can catalyze H2 at 120℃ and are not affected by moisture. Palladium nanoparticle / alumina (Pd / Al2O3) catalyst is loaded on test thermal stack b. Pd nanoparticles can catalyze CH4 at 400℃. Reference thermal stack a and reference thermal stack b serve as references for the two test thermal stacks, respectively.

[0065] A heating voltage (V) is applied to the annular heaters 40 of the reference thermal reactor a and the test thermal reactor b respectively through the heating electrode 60. H1 The annular heater 40 heats both the reference hot stack a and the test hot stack a to 120°C, ensuring that the catalyst 80Pt / Al2O3 operates at its optimal H2 catalytic temperature. During the test, the output electrode 70 of the test hot stack a generates an output voltage (V). s1 The output electrode 70 of the reference hot stack a generates an output voltage (V). r1 A heating voltage (V) is applied to the annular heaters 40 of the reference thermal reactor b and the test thermal reactor b respectively through the heating electrode 60. H2 The annular heater 40 heats both the reference thermal reactor b and the test thermal reactor b to 400°C, ensuring that the catalyst 80Pd / Al2O3 operates at a suitable temperature for CH4 catalysis. The output electrode 70 of the test thermal reactor b generates an output voltage (V). s2 The output electrode 70 of the reference thermal stack b generates an output voltage (V). r2 ).

[0066] like Figure 5 The diagram shows the response curves of the MEMS thermal stack array chip to H2 and CH4. When only air is introduced, no catalytic reaction occurs, and the output differential voltage ΔV is almost 0. However, when a mixture of hydrogen, methane, and air at 1000 ppm is introduced, catalyst 80 catalyzes an exothermic oxidation reaction, and the output signals of thermal stack units a and b are differentiated to output a corresponding differential voltage ΔV. When switching back to only air, the differential voltage ΔV is almost 0. The response time is the time required for the chip to reach 90% of its stable value from the point of exposure to the target gas, and the recovery time is the time required for the chip to recover to 10% of its initial baseline value from the point of removal from the target gas environment. Figure 5 It can be observed that the chip's response recovery time to H2 is 0.6s, and its response recovery time to CH4 is 0.9s.

[0067] The gas detection performance of the thermal stack array chip was calibrated. Figure 6 The chip's detection range and detection limit for a single component (H2 or CH4) are demonstrated. When mixed gases of different concentrations are introduced into the test chamber, a linear relationship between the differential output voltage ΔV and the gas concentration is observed. Furthermore, the thermally stacked array chip exhibits a detection range of 0.5ppm-2% for H2 and 1ppm-2% for CH4, spanning four orders of magnitude.

[0068] like Figure 7 The image shows the detection concentration results of a mixture of H2 and CH4 gases by a MEMS thermal stack array chip. Firstly, through... Figure 6 The concentration-output voltage curves of test thermal reactors a and b for H2 and CH4 were calibrated to obtain the sensitivity (slope of the straight line). Then, the mixed gas was detected, and the output signals ΔV1 and ΔV2 were obtained, from which the concentrations of H2 and CH4 could be calculated. Experimental results show that for mixed gases with different ratios, the H2 concentration range of 50–4000 ppm and the CH4 concentration range of 400–19000 ppm, the MEMS thermal reactor array chip can detect the concentrations of hydrogen and methane separately, with the deviation between the detected value and the set value being less than 5%.

[0069] The MEMS hot-pile array chip of the present invention has several hot-pile unit groups, and the output voltage (V) of hot-pile 2 is tested. sn ) and the output voltage (V) of the reference thermal pile 1 rn After differentiation, the differential signal ΔV is used. n (ΔV n =V sn -V rn This sensor is used to detect the concentration of various target combustible gas molecules. It features a low detection limit (0.5-1ppm), a wide linear range (spanning four orders of magnitude), and a short response recovery time (<1 second). Compared with existing sensors, it has superior and more comprehensive performance and can detect the concentration of multiple components of gas, showing promising application prospects.

[0070] Further need to be explained is that in the application, the support film 20 is a three-layer structure, and the plurality of polycrystalline silicon thermocouple pairs 30 are wrapped between the two layers of support film 20. The three-layer support film 20 and the polycrystalline silicon thermocouple pairs 30 can be obtained by chemical vapor deposition, which makes the thickness of the polycrystalline silicon thermocouple pairs 30 and the support film 20 thinner, and the heat capacity of the support film 20 smaller. After the catalytic reaction releases heat, the support film 20 absorbs heat and heats up faster, and the response time of the device is shorter, and the device is more sensitive to lower concentration gas heat release. At the same time, the thinner support film 20 makes it heat up more when absorbing the same amount of heat, and it is more sensitive to lower concentration gas heat release. At the same time, it dissipates less heat to the outside world, which makes the power required to heat to the same temperature smaller, which is beneficial to reduce the power consumption of the MEMS thermal pile array chip 101.

[0071] On the other hand, in the application, the temperature uniformity of the central heating area of the support film 20 is improved by the setting of the heat uniformizing metal 50, referring to Figures 8-9 The temperature uniformity of the central heating area of the support film 20 is tested, and it can be seen that when the heat uniformizing metal 50 exists, the temperature deviation is ±5℃, that is, the temperature deviation of the heating area of the device is only about 1%, which is obviously better than the device without the heat uniformizing metal 50. Better temperature uniformity can heat the catalyst 80 more evenly, thereby improving the signal strength and realizing the detection of lower concentration gas.

[0072] Example three

[0073] Referring to Figure 10 The application also provides a multi-component gas detection device, which comprises the above-mentioned MEMS thermal pile array chip 101, and further comprises

[0074] The shell 102 is composed of two parts, and the shell 102 has a display screen 106 on the upper part;

[0075] The test circuit 103 is installed in the shell 102 and electrically connected with the display screen 106;

[0076] The PCB board 104 is plugged on the test circuit 103, and the PCB board 104 has a test cavity, and the MEMS thermal pile array chip 101 is installed in the test cavity;

[0077] The battery 105 is installed in the shell 102 and used to power the test circuit 103.

[0078] Specifically, referring to Figure 11The test circuit 103 includes a heating, reading circuit and a control, processing circuit. The heating, reading circuit includes a power supply module, a heating module and a multi-channel signal reading module. The control, processing circuit includes a heating control module, a signal processing module and a screen display module. The heating module is responsible for converting the PWM heating voltage into an analog signal and providing the chip heater. The multi-channel signal reading module collects the output voltage of each heat stack, transmits it to the data processing module after filtering and amplification. The data processing module changes the heat stack heating voltage by adjusting the duty cycle of the PWM signal, thereby adjusting the heat stack temperature, converts the heat stack output voltage into a digital signal using a 12-bit ADC, and transmits it to the screen after calculation and processing by the STM32.

[0079] The above examples are only used to illustrate the technical solutions of the present application, and not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A MEMS thermal stack array chip, characterized in that: The system includes a silicon substrate, on which a plurality of thermal stack unit groups are arrayed. Each thermal stack unit group includes a reference thermal stack and a test thermal stack. Both the reference thermal stack and the test thermal stack include... A heat-insulating cavity is formed on the upper surface of the silicon substrate; A three-layer support membrane is disposed on the heat insulation cavity; Several polycrystalline silicon thermocouple pairs are connected in series and wrapped between two supporting films below. The several polycrystalline silicon thermocouple pairs are arranged in a centrally symmetrical manner, with their hot ends located in the central region of the supporting film and their cold ends located in the edge region of the supporting film. An annular heater is wrapped between the two supporting films and located above the hot ends of the plurality of polycrystalline silicon thermocouple pairs; The uniformly heated metal is wrapped between the two supporting films and located in the middle of the annular heater; A heating electrode is disposed on the silicon substrate and electrically connected to the annular heater; The output electrode is disposed on the silicon substrate and electrically connected to the plurality of polycrystalline silicon thermocouples; The test thermal reactor also includes a catalyst, which is located on the surface of the uppermost support membrane and covers the homogenizing metal.

2. The MEMS hot-pile array chip according to claim 1, characterized in that: The uniformly heated metal is ring-shaped and made of metallic Mo.

3. A MEMS hot-pile array chip according to claim 1, characterized in that: The material of the support membrane is silicon nitride.

4. A MEMS hot-pile array chip according to claim 1, characterized in that: The polycrystalline silicon thermocouple pair has a linear structure.

5. A multi-component gas detection device, comprising a MEMS thermal stack array chip according to any one of claims 1-4, characterized in that: Also includes A housing having a display screen; The test circuit is installed inside the housing and is electrically connected to the display screen; A PCB board is inserted into the test circuit. The PCB board has a test cavity, and the MEMS hot stack array chip is installed in the test cavity. A battery, installed inside the housing, is used to power the test circuit.

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