Gas sensor chip

Abstract

The gas sensor chip comprises a measurement unit and a compensation unit, the measuring unit comprises a substrate, a supporting layer and a first thermocouple element; the substrate is connected with the supporting layer which is connected with the first thermocouple element. The compensation unit comprises a substrate, a supporting layer and a second thermocouple element; the second thermocouple element is connected with the supporting layer; the compensation unit is provided with a compensation cavity, and the compensation cavity is communicated with the outside of the gas sensor chip; the first thermocouple element comprises a first galvanic couple layer, a first insulating layer and a second galvanic couple layer; the first galvanic couple layer is connected with the supporting layer, and the second galvanic couple layer is connected with the first insulating layer; in the thickness direction of the gas sensor chip, the first galvanic couple layer and the second galvanic couple layer are located on the two sides of the first insulating layer respectively, and the obtained gas sensor chip is small in size.

Description

Technical Field

[0001] The invention belongs to the technical field of sensors, and in particular relates to a gas sensor chip. Background Art

[0002] At present, as human beings have fully entered the era of intelligent information, the demand for information measurement and control is getting higher and higher. Among them, the measurement and control of gas concentration is of great significance in the fields of biomedicine, aerospace, industrial automation, etc. With the continuous advancement of MEMS technology, thermal conductivity gas sensors manufactured based on MEMS technology have become an important direction for the future development of gas concentration sensors due to their advantages such as high sensitivity, low power consumption and fast response time.

[0003] In the related art, infrared thermopile gas concentration sensors need to eliminate environmental factors such as the influence of temperature and humidity on gas concentration when detecting gas concentration; therefore, independent detection sensors need to be installed separately when detecting gas concentration, which results in a large size of the gas sensor and brings inconvenience to the application of the product. Summary of the invention

[0004] The purpose of the present application is to provide a gas sensor chip, comprising a measuring unit and a compensation unit; the measuring unit comprises a substrate, a supporting layer and a first thermocouple element; the substrate is connected to the supporting layer, and the supporting layer is connected to the first thermocouple element;

[0005] The compensation unit includes the substrate, the support layer and a second thermocouple element; the second thermocouple element is connected to the support layer; the compensation unit has a compensation cavity, the compensation cavity is connected to the outside, and along the thickness direction of the chip, the second thermocouple element and the compensation cavity are located on both sides of the support layer;

[0006] The first thermocouple element includes a first electric double layer, a first insulating layer, and a second electric double layer; the first electric double layer is connected to the supporting layer, and the second electric double layer is connected to the first insulating layer; along the thickness direction of the chip, the second electric double layer is away from the first insulating layer.

[0007] In the present application, the gas sensor chip includes a measuring unit and a compensation unit. The compensation unit is used to compensate for the influence of factors such as temperature and humidity in the environment on the measuring unit. At the same time, the structure of the first thermocouple element in the measuring unit and the structure of the second thermocouple element in the compensation unit are arranged in a stacked manner, and the resulting gas sensor chip is smaller in size. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a cross-sectional schematic diagram of a gas sensor chip;

[0009] Figure 2 for Figure 1 Schematic diagram of the measuring unit;

[0010] Figure 3 for Figure 1 Schematic diagram of the compensation unit;

[0011] Figure 4 for Figure 1 A magnified schematic diagram of A in the measurement unit;

[0012] Figure 5 A top view schematic diagram of a measurement unit in a gas sensor chip;

[0013] Figure 6 Schematic diagram of a top view of the compensation unit in the gas sensor chip. DETAILED DESCRIPTION

[0014] The exemplary embodiments of the present application are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can be combined with each other.

[0015] Figure 1 This is a cross-sectional view of the gas sensor chip in the present application, wherein the gas sensor chip comprises a measuring unit 1 and a compensation unit 2; the measuring unit 1 comprises a substrate 11, a supporting layer 12 and a first thermocouple element 14; the substrate 11 is connected to the supporting layer 12, and the supporting layer 12 is connected to the first thermocouple element 14; the measuring unit 1 and the compensation unit 2 are integrated on a sensor chip, which has fewer components than the infrared gas sensor chip in the related art.

[0016] In some embodiments of the present application, the schematic diagram of the compensation unit 2 is as follows: Figure 3 As shown; the compensation unit 2 includes a substrate 11, a support layer 12 and a second thermocouple element 22; the second thermocouple element 22 is connected to the support layer 12; the compensation unit 2 has a compensation cavity 24, the compensation cavity 24 is connected to the outside of the gas sensor chip, and is exposed to gases of different concentrations, and the heat generated by the gas is diluted through the compensation cavity 24, thereby compensating the measuring unit 1, and along the thickness direction Z of the gas sensor chip, the second thermocouple element 22 and the compensation cavity 24 are respectively located on both sides of the support layer 12.

[0017] In some embodiments of the present application, the first thermocouple element 14 includes a first electric double layer 141, a first insulating layer 142, and a second electric double layer 143; the first electric double layer 141 is connected to the support layer 12, and the second electric double layer 143 is connected to the first insulating layer 142; along the thickness direction Z of the gas sensor chip, the first electric double layer 141 and the second electric double layer 143 are respectively located on both sides of the first insulating layer 142. The first electric double layer 141, the first insulating layer 142, and the second electric double layer 143 in the first thermocouple element 14 are connected in a stacked manner, so that the volume of the first thermocouple element 14 is small, and more first thermocouple elements 14 can be arranged on the surface of the support layer 12 to sense more heat, so as to output a larger potential difference, and further improve the test accuracy of the gas sensor chip.

[0018] In some embodiments of the present application, the schematic diagram of the measuring unit 1 is as follows: Figure 2 As shown; the measuring unit 1 has a measuring cavity 15, which is at least partially located in the substrate 11; along the thickness direction Z of the gas sensor chip, the measuring cavity 15 and the first thermocouple element 14 are respectively located on both sides of the supporting layer 12; wherein the volume of the measuring cavity 15 is smaller than the volume of the compensation cavity 24.

[0019] The gas passes through the gas sensor chip and enters the measuring cavity 15 and the compensating cavity 24 respectively. The measuring cavity 15 and the compensating cavity 24 can achieve good heat insulation and heat preservation for the heat of the gas, and reduce the heat loss, that is, the power consumption is small; since the volume of the compensating cavity 24 is large, the concentration of the gas can be diluted after entering the compensating cavity 24, and the heat emitted by the gas is absorbed by the substrate 11, while the volume of the measuring cavity 15 in the measuring unit 1 is relatively small, and the first thermocouple element 14 can better sense the potential difference caused by the heat of the gas, and then output an electrical signal; since the heat generated by gases of different concentrations is different, the first thermocouple element 14 can sense different electrical signals, and the gas concentration can be inferred according to the strength of the output electrical signal; the compensation unit 2 can be used to compensate for environmental factors, gas flow rate, etc., and the calculation formula of its working principle is as follows:

[0020]

[0021] Where: ΔP is the power difference between the measuring unit 1 and the compensation unit 2, ΔT is the temperature difference between the measuring unit 1 and the compensation unit 2; λ g is the thermal conductivity of the gas, A is the membrane area of ​​the support layer 12 , and d is the cavity depth of the measuring unit 2 .

[0022] It should be noted that the above A, which is the membrane area of ​​the support layer 12 , refers to the support layer 12 contacting the measuring cavity 15 or the compensating cavity 24 , wherein the cross-sectional area of ​​the measuring cavity 15 is the same as that of the compensating cavity 24 .

[0023] In some embodiments of the present application, the depth of the measurement cavity 15 is 1-3 μm; the depth of the compensation cavity 24 is 150-250 μm.

[0024] In the present application, the ratio of the volume of the measuring cavity 15 to the compensation cavity 24 is 1:100-200; if the ratio of the volume of the measuring cavity 15 to the compensation cavity 24 is too high, the compensation unit 2 may not be able to compensate the measuring unit 1; conversely, if the ratio is too low, the compensation effect of the compensation unit 2 on the measuring unit 1 will not change significantly, thereby increasing the manufacturing cost. Therefore, in the present application, the measuring cavity 15 and the compensation cavity 24 adopt a suitable volume ratio and depth, which can enable the compensation unit to achieve a better compensation effect on the measuring unit, and the operation process is simple.

[0025] In some embodiments of the present application, the compensation cavity 24 penetrates the substrate 11 along the thickness direction Z of the gas sensor chip.

[0026] It should be noted that the substrate and the packaging device are located on both sides of the compensation cavity 24, and the bottom of the substrate and the packaging device can be bonded and packaged with glue. The packaging device is preferably a TO tube socket.

[0027] In some embodiments of the present application, the measuring unit 1 includes a first heating element 16, the first heating element 16 is at least partially connected to the supporting layer 12, and along the thickness direction Z of the gas sensor chip, the first heating element 16 and the measuring cavity 15 are respectively located on both sides of the supporting layer 12; the first heating element 16 is selected from one or more of platinum, tungsten, nickel-chromium alloy and iron-chromium alloy; platinum and tungsten are preferred, and platinum is more preferred. The second heating element 23 is used to heat gases of different concentrations, and the second heating element 23 outputs electrical signals of different strengths, thereby measuring the size of the gas concentration.

[0028] In some embodiments of the present application, the enlarged schematic diagram of the first thermocouple element 14 is as follows: Figure 4As shown; along the thickness direction Z of the gas sensor chip, the first electric double layer 141 of the first thermocouple element 14 is covered on at least part of the support layer 12, the first insulating layer 142 is covered on part of the first electric double layer 141, and the second electric double layer 143 is covered on part of the first insulating layer 142; the direction perpendicular to the thickness direction Z is defined as the horizontal direction X, and along the horizontal direction X of the gas sensor chip, the length of the first electric double layer 141 is greater than the first insulating layer 142 and the second electric double layer 143, and the length of the first insulating layer 142 is greater than the second electric double layer 143. The first electric double layer 141, the first insulating layer 142 and the second electric double layer 143 of the first thermocouple element 14 are connected in a stacked manner, which reduces the area of ​​the first thermocouple element 14, and along the length direction X of the gas sensor chip, the first electric double layer 141 is greater than the first insulating layer 142 and the second electric double layer 143, which facilitates the electrical connection of the first electric double layer 141 and the second electric double layer 143 in the subsequent process, thereby reducing the difficulty of the manufacturing process.

[0029] In some embodiments of the present application, the first insulating layer 142 is selected from silicon dioxide or silicon nitride; the first electric double layer 141 is selected from P-type polysilicon, and the second electric double layer 143 is selected from N-type polysilicon or aluminum; or, the first electric double layer 141 is selected from N-type polysilicon, and the second electric double layer 143 is selected from P-type polysilicon or aluminum; or, the first electric double layer 141 is selected from aluminum, and the second electric double layer 143 is selected from P-type polysilicon or N-type polysilicon.

[0030] Further, in some embodiments of the present application, the first insulating layer 142 is selected from silicon dioxide, the first electric double layer 141 is selected from N-type polysilicon, and the second electric double layer 143 is selected from P-type polysilicon; or, the first insulating layer 142 is selected from silicon nitride, the first electric double layer 141 is selected from N-type polysilicon, and the second electric double layer 143 is selected from P-type polysilicon. By using materials with different Seebeck coefficients as the first electric double layer 141 and the second electric double layer 143 of the first thermocouple element 14, different concentrations of gas output different strengths of electrical signals, the temperature in the measuring unit 1 can be better measured, thereby improving the test accuracy of the sensor chip.

[0031] In some embodiments of the present application, the gas sensor chip includes a first wire 13 and a second wire 17; the first wire 13 electrically connects the first electric couple layer 141 of a first thermocouple element 14 with the second electric couple layer 143 of another adjacent first thermocouple element 14; the second wire 17 electrically connects the first electric couple layer 141 and the second electric couple layer 143 of the same first thermocouple element 14, and the first wire 13 and the first thermocouple element 14 are located on the same side of the support layer 12.

[0032] In some embodiments of the present application, a direction perpendicular to the thickness direction Z is defined as a horizontal direction X. Along the horizontal direction X of the gas sensor chip, at least portions of the first wire 13 and the second wire 17 are respectively located on both sides of the same first thermocouple element 14; the second wire 17 is closer to the first heating element 16 relative to the first wire 13 to sense the potential difference generated by different gas concentrations, and then output an electrical signal.

[0033] In some embodiments of the present application, the first wire 13 electrically connects the first electric couple layer 141 of a first thermocouple element 14 with the second electric couple layer 143 of another adjacent first thermocouple element 14, and so on. After the first wire 13 connects the first thermocouple elements 14 in series, the first electric couple layer 141 of the first thermocouple element 14 connected first and the second electric couple layer 143 of the last connected first thermocouple element 14 are respectively connected to the positive electrode and the negative electrode of the metal pad to output a voltage signal. Each first thermocouple element 14 is preferably arranged in a circular shape. The first thermocouple element 14 is arranged in a circular ring-shaped manner around the measuring cavity 15, so that more first thermocouple elements 14 can be arranged around the measuring cavity 15 to concentrate on sensing the heat of gases of different concentrations, and then output voltage differences of different sizes through each first thermocouple element 14, so as to more accurately infer the concentration of the gas, thereby improving the measurement accuracy of the gas sensor chip, and at the same time reducing the stress concentration of the first thermocouple element 14, so that the chip can withstand rapid temperature changes, thereby increasing the service life of the gas sensor chip.

[0034] In some embodiments of the present application, the second thermocouple element 22 includes a third electric couple layer 221, a second insulating layer 222, and a fourth electric couple layer 223; the third electric couple layer 221 is connected to the second insulating layer 222, and the second insulating layer 222 is connected to the fourth electric couple layer 223; along the thickness direction Z of the gas sensor chip, the fourth electric couple layer 223 and the third electric couple layer 221 are respectively located on both sides of the second insulating layer 222. The third electric couple layer 221, the second insulating layer 222, and the fourth electric couple layer 223 in the second thermocouple element 22 are arranged in a stacked manner, which can reduce the volume of the second thermocouple element 22, and then more second thermocouple elements 22 are arranged on the substrate 11, thereby improving the test accuracy of the gas sensor chip.

[0035] In some embodiments of the present application, the compensation unit 2 includes a second heating element 23; the second heating element 23 is at least partially connected to the support layer 12, and along the thickness direction Z of the gas sensor chip, the second heating element 23 and the compensation cavity 25 are respectively located on both sides of the support layer 12; the second heating element 23 is selected from one or more of platinum, tungsten, nickel-chromium alloy and iron-chromium alloy, and platinum and tungsten are specifically preferred, and platinum is more preferred.

[0036] In some embodiments of the present application, the gas sensor chip includes a third wire 21 and a fourth wire 26; the third wire 21 electrically connects the third electric double layer 221 and the fourth electric double layer 223 of the same second thermocouple element 22; the fourth wire 26 electrically connects the third electric double layer 221 of one second electric double element 22 and the fourth electric double layer 223 of another adjacent second electric double element 22.

[0037] In some embodiments of the present application, a direction perpendicular to the thickness direction Z is defined as a horizontal direction X. Along the horizontal direction X of the gas sensor chip, at least portions of the third wire 21 and the fourth wire 26 are respectively located on both sides of the same second thermocouple element 22; the fourth wire 26 is closer to the second heating element 23 relative to the third wire 21 to sense the potential difference generated by different gas concentrations, and then output an electrical signal.

[0038] In some embodiments of the present application, the fourth wire 26 electrically connects the third electric couple layer 221 of a second electric couple element 22 with the fourth electric couple layer 223 of another adjacent second electric couple element 22. By analogy, after the fourth wire 26 connects the second thermocouple elements 22 in series, the third electric couple layer 221 of the second thermocouple element 22 connected first and the fourth electric couple layer 223 of the second thermocouple element 22 connected last are respectively connected to the positive and negative electrodes of the metal pad to output a voltage signal. Each second thermocouple element 22 can be arranged around the compensation cavity 24 in a circular, square or rectangular manner; preferably in a circular shape, the second thermocouple element 22 is arranged around the compensation cavity 24 in a circular manner, which can reduce the stress concentration of the second thermocouple element 22, improve the stability of the second thermocouple element 22 in the sensor chip, and enable the sensor chip to withstand rapid temperature changes, thereby increasing the service life of the gas sensor chip.

[0039] In some embodiments of the present application, the second insulating layer 222 is selected from silicon dioxide or silicon nitride; the third electric double layer 221 is selected from P-type polysilicon, and the fourth electric double layer 223 is selected from N-type polysilicon or aluminum; or, the third electric double layer 221 is selected from N-type polysilicon, and the fourth electric double layer 223 is selected from P-type polysilicon or aluminum; or, the third electric double layer 221 is selected from aluminum, and the fourth electric double layer 223 is selected from P-type polysilicon or N-type polysilicon. By using materials with different Seebeck coefficients as the third electric double layer 221 and the fourth electric double layer 223 of the second thermocouple element 22, different strengths of electrical signals are output through different concentrations of gas, so that the temperature in the compensation unit 2 can be better measured.

[0040] Further, in some embodiments of the present application, the second insulating layer 222 is selected from silicon dioxide, the third electric double layer 221 is selected from N-type polysilicon, and the fourth electric double layer 223 is selected from P-type polysilicon; or, the second insulating layer 222 is selected from silicon nitride, the third electric double layer 221 is selected from N-type polysilicon, and the fourth electric double layer 223 is selected from P-type polysilicon.

[0041] In some embodiments of the present application, an electric double layer a is deposited on a portion of the surface of the support layer 12 by a deposition process, the electric double layer is etched by photolithography and dry etching processes, and a graphic definition is performed to obtain a first electric double layer 141 and a third electric double layer 221 respectively; an insulating layer is deposited on at least a portion of the surface of the electric double layer a by a deposition process, the insulating layer is etched by photolithography and dry etching processes, and a graphic definition is performed to obtain a first insulating layer 142 and a second insulating layer 222 respectively; an electric double layer b is deposited on at least a portion of the surface of the insulating layer by a deposition process, the electric double layer b is etched by photolithography and dry etching processes, and a graphic definition is performed to obtain a third electric double layer 221 and a fourth electric double layer 223 respectively.

[0042] Furthermore, in some embodiments of the present application, a direction perpendicular to the thickness direction Z is defined as a horizontal direction X, wherein along the horizontal direction X of the gas sensor chip, the length of the first electric double layer 141 is greater than the first insulating layer 142, and the length of the first insulating layer 142 is greater than the second electric double layer 143; the length of the third electric double layer 221 is greater than the second insulating layer 222, and the length of the second insulating layer 222 is greater than the fourth electric double layer 223, so that the subsequent deposition of the second wire 17 and the fourth wire 26 is relatively simple.

[0043] The present application adopts a deposition process to sequentially deposit an a-electric couple layer, an insulating layer and a b-electric couple layer on a partial surface of the support layer 12, and then adopts photolithography and dry etching processes and performs graphic definition to obtain the first thermocouple element 14 in the measuring unit 1 and the second thermocouple element 22 in the compensation unit, and then integrates the measuring unit 1 and the compensation unit 2 on the gas sensor chip at the same time, thereby reducing the volume of the gas sensor chip. Compared with the infrared gas sensor in the related art, it has fewer components and lower cost.

[0044] In some embodiments of the present application, the deposition process used in the present application is selected from one of LPCVD, APCVD, PECVD and PVD.

[0045] In some embodiments of the present application, a wire element is deposited on at least a portion of the surface of the support layer 12, and is graphically defined by photolithography, dry etching, or a stripping process to etch out the first wire 13, the second wire 17, the third wire 21, and the fourth wire 26; the deposition process can deposit the wire element on the stacked structure of the first thermocouple element 14 and the second thermocouple element 22 designed in the present application in the same direction, and then the wire element is etched by photolithography, dry etching, or a stripping process, and the operation process is simple and has high precision.

[0046] In some embodiments of the present application, the top views of the measuring unit 1 and the compensation unit 2 of the gas sensor chip are respectively as follows: Figure 5 , 6 As shown; CeF2 gas is used to etch holes 19 on at least part of the surface of the support layer 12, and dry etching is used to etch the measurement cavity 15 through the hole 19; CeF2 gas is used to etch holes 25 on at least part of the surface of the support layer 12, and the compensation cavity 24 is etched through the hole 25. The present application uses photolithography and dry etching processes to etch the measurement cavity 15 and the compensation cavity 24 through the hole 19 and the hole 25 on the same side of the substrate 11, respectively, wherein the etching processes of the measurement cavity 15 and the compensation cavity 24 have no order, and compared with the related art that uses wet etching process to etch the cavity, the operation is simple, no chemical reagents are required, and the cost is low.

[0047] The above implementation modes are only used to illustrate the present application and are not intended to limit the technical solutions described in the present application. The understanding of the present application should be based on the technical personnel in the relevant technical field. Although the present application has been described in detail in this specification with reference to the above implementation modes, ordinary technical personnel in the field should understand that the technical personnel in the relevant technical field can still modify or make equivalent substitutions to the present application, and all technical solutions and improvements thereof that do not depart from the spirit and scope of the present application should be included in the scope of the claims of the present application.

Claims

1. A gas sensor chip, characterized in that: The gas sensor chip comprises a measuring unit (1) and a compensation unit (2); the measuring unit (1) comprises a substrate (11), a supporting layer (12) and a first thermocouple element (14); the substrate (11) is connected to the supporting layer (12), and the supporting layer (12) is connected to the first thermocouple element (14); The compensation unit (2) comprises the substrate (11), the support layer (12) and a second thermocouple element (22); the second thermocouple element (22) is connected to the support layer (12); the compensation unit (2) has a compensation cavity (24), the compensation cavity (24) is connected to the outside of the gas sensor chip, and along the thickness direction (Z) of the gas sensor chip, the second thermocouple element (22) and the compensation cavity (24) are respectively located on both sides of the support layer (12); The first thermocouple element (14) comprises a first electric double layer (141), a first insulating layer (142) and a second electric double layer (143); the first electric double layer (141) is connected to the support layer (12), and the second electric double layer (143) is connected to the first insulating layer (142); along the thickness direction (Z) of the gas sensor chip, the first electric double layer (141) and the second electric double layer (143) are respectively located on both sides of the first insulating layer (142).

2. A gas sensor chip, characterized in that: The gas sensor chip comprises a measuring unit (1) and a compensation unit (2), wherein the measuring unit (1) and the compensation unit (2) are arranged at an interval; The gas sensor chip comprises a substrate (11) and a support layer (12); the measuring unit (1) comprises a first thermocouple element (14); the substrate (11) is located on one side of the support layer (12); and the first thermocouple element (14) is located on the other side of the support layer (12); The first thermocouple element (14) comprises a first electric double layer (141), a first insulating layer (142) and a second electric double layer (143); the first electric double layer (141) is covered on at least a portion of the support layer (12); the first insulating layer (142) is covered on a portion of the first electric double layer (141); the second electric double layer (143) is covered on a portion of the first insulating layer (142); along the thickness direction (Z) of the gas sensor chip, the second electric double layer (143) is away from the support layer (12) relative to the first electric double layer (141).

3. The gas sensor chip according to claim 2, characterized in that: The compensation unit (2) comprises a second thermocouple element (22), the second thermocouple element (22) is connected to the support layer (12), the compensation unit (2) has a compensation cavity (24), the compensation cavity (24) is connected to the outside of the gas sensor chip, and along the thickness direction (Z) of the gas sensor chip, the second thermocouple element (22) and the compensation cavity (24) are respectively located on both sides of the support layer (12).

4. The gas sensor chip according to any one of claims 1 to 3, characterized in that: The measuring unit (1) has a measuring cavity (15), wherein the measuring cavity (15) is at least partially located in the substrate (11); along the thickness direction (Z) of the gas sensor chip, the measuring cavity (15) and the first thermocouple element (14) are respectively located on both sides of the support layer (12); the volume of the measuring cavity (15) is smaller than the volume of the compensation cavity (24); the depth of the measuring cavity (15) is 1 to 3 μm; the depth of the compensation cavity (24) is 150 to 250 μm, or, Along the thickness direction (Z) of the gas sensor chip, the compensation cavity (24) penetrates the substrate (11).

5. The gas sensor chip according to claim 4, characterized in that: The measuring unit (1) comprises a first heating element (16), the first heating element (16) being at least partially connected to the supporting layer (12); along the thickness direction (Z) of the gas sensor chip, the first heating element (16) and the measuring cavity (15) are respectively located on two sides of the supporting layer (12); the first heating element (16) is selected from one or more of platinum, tungsten, nickel-chromium alloy and iron-chromium alloy.

6. The gas sensor chip according to claim 1 or 2, characterized in that: The first insulating layer (142) is selected from silicon dioxide or silicon nitride; the first electric double layer (141) is selected from P-type polysilicon, and the second electric double layer (143) is selected from N-type polysilicon or aluminum; or, The first electric double layer (141) is selected from N-type polysilicon, and the second electric double layer (143) is selected from P-type polysilicon or aluminum; or The first electric double layer (141) is selected from aluminum, and the second electric double layer (143) is selected from P-type polysilicon or N-type polysilicon.

7. The gas sensor chip according to claim 1 or 2, characterized in that: The gas sensor chip comprises a first wire (13) and a second wire (17); the first wire (13) electrically connects a first electric couple layer (141) of a first thermocouple element (14) with a second electric couple layer (143) of another adjacent first thermocouple element (14); and the second wire (17) electrically connects the first electric couple layer (141) and the second electric couple layer (143) of the same first thermocouple element (14).

8. The gas sensor chip according to claim 7, characterized in that: A direction perpendicular to the thickness direction (Z) is defined as a horizontal direction (X); along the horizontal direction (X) of the gas sensor chip, at least parts of the first wire (13) and the second wire (17) are respectively located on both sides of the same first thermocouple element (14); and the second wire (17) is closer to the first heating element (16) relative to the first wire (13).

9. The gas sensor chip according to claim 1 or 2, characterized in that: The second thermocouple element (22) comprises a third electric double layer (221), a second insulating layer (222) and a fourth electric double layer (223); the third electric double layer (221) is connected to the second insulating layer (222), and the second insulating layer (222) is connected to the fourth electric double layer (223); along the thickness direction (Z) of the gas sensor chip, the fourth electric double layer (223) and the third electric double layer (221) are respectively located on both sides of the second insulating layer (222); The compensation unit (2) comprises a second heating element (23); the second heating element (23) is at least partially connected to the support layer (12); the second heating element (23) is selected from one or more of platinum, tungsten, nickel-chromium alloy and iron-chromium alloy.

10. The gas sensor chip according to claim 9, characterized in that: The second insulating layer (222) is selected from silicon dioxide or silicon nitride; the third electric double layer (221) is selected from P-type polysilicon, and the fourth electric double layer (223) is selected from N-type polysilicon or aluminum; or, The third electric double layer (221) is selected from N-type polysilicon, and the fourth electric double layer (223) is selected from P-type polysilicon or aluminum; or, The third electric double layer (221) is selected from aluminum, and the fourth electric double layer (223) is selected from P-type polysilicon or N-type polysilicon.

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