Gas sensor with heating desorption function

Abstract

The invention provides a gas sensor with a heating desorption function, which comprises the following components from bottom to top: a substrate which is used for supporting the whole gas sensor and has high thermal conductivity; the detection-heating electrode comprises a snakelike electrode and an inverted F-shaped electrode; the snakelike electrode is arranged near the inverted F-shaped electrode and is arranged along the inverted F-shaped electrode; the head of the snakelike electrode is a No.1 electrode, and the tail of the snakelike electrode is a No.2 electrode; the head part of the inverted F-shaped electrode is a No.3 electrode; the No.1 electrode is grounded when the gas sensitive sensor is in a normal working state; the detection-heating electrode is made of a conductive material through a sputtering or evaporation process, is used as a detection electrode, and is also used as a heating electrode for desorption when needed; the sensitive material coating is formed by uniformly coating a sensitive material on the detection-heating electrode by adopting a spin coating or sputtering technology and is used for detecting the adsorption and desorption processes of gas molecules; the sensitive material is a gas sensitive material. The detection frequency is improved, and the service life of the sensor is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of gas sensors, and in particular to a gas sensor structure with a heating function for improving the sensitivity and life of the gas sensor. The structure can realize rapid desorption of sensing materials through active heating, and is suitable for sensor equipment for detecting gas environments. Background Art

[0002] Sensors have important applications in modern industry and agriculture, information technology, environmental monitoring and other fields. As an important branch of sensors, gas sensors have become the focus of sensor research and development in recent years and are the future development of sensors. One of the directions. Gas sensor technology has a broad application prospect and can be used for the detection of various flammable, explosive or harmful gases in factories, workshops and mines, and the monitoring and detection of flammable gas leaks in households. This sensor is mainly an electronic device made based on the principle that the surface resistance of the gas-sensitive material layer on it changes when it encounters the target gas (the gas being measured).

[0003] During the long-term use of gas sensors, physical or chemical adsorption between gas molecules and the sensitive material of the sensor may produce an adsorption effect. This adsorption effect will affect the subsequent detection sensitivity and accuracy of the sensor, resulting in distortion of measurement data and reduced sensor sensitivity. The traditional solution is to heat the sensor through an external heat source to desorb the gas molecules on the sensitive material. However, the external heating device not only increases the complexity of the equipment, but also brings problems of increased power consumption and increased volume.

[0004] In order to overcome the defects in the prior art, the present invention provides a gas sensor with a built-in heating function. By integrating a heating electrode, the sensitive material can be actively heated after gas detection is completed, thereby achieving rapid desorption and improving the service life and detection accuracy of the sensor. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a gas sensor with a heating desorption function. Through the built-in heating electrode, after the gas detection is completed, the sensitive material is heated by applying voltage to achieve the desorption effect, thereby avoiding the influence of long-term adsorption of gas molecules on the sensing performance, thereby improving the detection frequency and the service life of the sensor.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows: The present invention provides a gas sensor with heating desorption function, which comprises the following components from bottom to top: A substrate, which is used to support the entire gas sensor and has high thermal conductivity; Detection-heating electrode: including a serpentine electrode and an inverted F-type electrode; the serpentine electrode is arranged near and along the inverted F-type electrode; the head of the serpentine electrode is electrode No. 1, and the tail is electrode No. 2; the head of the inverted F-type electrode is electrode No. 3; the electrode No. 1 is grounded under normal working conditions of the gas sensor; the detection-heating electrode is made of conductive material through sputtering or evaporation process, and is used as a detection electrode and as a heating electrode for desorption when needed; The sensitive material coating is a sensitive material uniformly coated on the detection-heating electrode by spin coating or sputtering technology, and is used to detect the adsorption and desorption process of gas molecules; the sensitive material is a gas-sensitive material.

[0007] Furthermore, the inverted F-shaped electrode has a plurality of integrally formed transverse electrodes; the serpentine electrode is arranged along the inverted F-shaped electrode and the transverse electrodes.

[0008] Furthermore, the substrate is made of a ceramic material with high thermal conductivity.

[0009] Furthermore, the substrate is made of aluminum oxide.

[0010] Furthermore, the detection-heating electrode is made of a metal material with good electrical conductivity and high temperature resistance through a sputtering or evaporation process.

[0011] Furthermore, the detection-heating electrode is made of platinum, gold or silver alloy by sputtering or evaporation process.

[0012] Furthermore, the sensitive material is made by coating tin oxide, zinc oxide or tungsten oxide on the surface of the detection-heating electrode by spin coating or sputtering technology.

[0013] A method for assembling a gas sensor with a heating desorption function comprises the following steps: Step 1. Clean and dry the substrate to ensure it is dust-free and pollution-free; Step 2. Fabricate a serpentine detection-heating electrode on the substrate by sputtering or evaporation process; Step 3. Use spin coating or sputtering technology to evenly coat the sensitive material on the electrode surface to complete the assembly of the gas sensor; Step 4. Package the gas sensor to ensure stability and reliability during use.

[0014] The method for using the above-mentioned gas sensor with heating desorption function comprises the following steps: During the gas detection process, the gas sensor is in normal working condition, electrode No. 3 is kept grounded, and the adsorption of gas molecules is determined by measuring the resistance change between electrode No. 1 and electrode No. 3; when the sensitive material needs to be desorbed, electrode No. 1 is grounded, and voltage is applied to electrode No. 2. The heat generated by the current is used to heat the sensitive material to desorb the gas molecules.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention uses a built-in heating electrode to heat the sensitive material by applying voltage after gas detection is completed, thereby achieving a desorption effect, avoiding the influence of long-term adsorption of gas molecules on the sensing performance, thereby increasing the detection frequency and the service life of the sensor.

[0016] 2. The substrate of the present invention is made of a material with high thermal conductivity to ensure the thermal stability of the sensor as a whole, especially to effectively conduct heat during the heating process to prevent the electrode temperature from being too high to damage the gas sensor.

[0017] 3. The serpentine electrode of the present invention adopts a curved serpentine design, which can maximize the heating area when current passes through, ensuring uniform heating of the sensitive material coating of the sensor.

[0018] 4. The sensitive material of the present invention is selected from common gas-sensitive materials, such as tin oxide (SnO2), zinc oxide (ZnO) or tungsten oxide (WO3), etc. These materials have good adsorption properties for gas molecules and can achieve rapid desorption reactions at high temperatures. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 It is a structural diagram of a detection-heating electrode of a gas sensor with a heating and desorption function according to an embodiment of the present invention.

[0021] Figure 2 The present invention is a flowchart of an assembly method of a gas sensor with a heating desorption function according to an embodiment of the present invention.

[0022] In the figure: electrode No. 1.1, electrode No. 2.2, electrode No. 3.3. DETAILED DESCRIPTION

[0023] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0024] The embodiments disclosed in the present invention are described by specific concrete examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0025] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0027] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0028] like Figure 1 As shown, a gas sensor with heating desorption function in this embodiment, from bottom to top, is respectively: The substrate is used to support the entire gas sensor; the substrate is made of a ceramic material with high thermal conductivity, and in this embodiment it is specifically made of alumina to ensure the overall thermal stability of the sensor, especially to effectively conduct heat during the heating process to prevent the electrode temperature from being too high to damage the sensor.

[0029] Detection-heating electrode: includes a serpentine electrode and an inverted F-type electrode. The serpentine electrode is arranged near and along the inverted F-type electrode. The head of the serpentine electrode is electrode No. 1 2, and the tail is electrode No. 2 2. The head of the inverted F-type electrode is electrode No. 3 3. Electrode No. 1 1 is grounded under normal working conditions of the gas sensor. The detection-heating electrode is made of a conductive material through a sputtering or evaporation process. It is used as a detection electrode and as a heating electrode for desorption when needed. There are also several integrally formed lateral electrodes on the inverted F-type electrode. The serpentine electrode is arranged along the inverted F-type electrode and the lateral electrode. The detection-heating electrode is made of a metal material with good conductivity and high temperature resistance through a sputtering or evaporation process. In this embodiment, the detection-heating electrode is made of platinum, gold or silver alloy through a sputtering or evaporation process. The shape design of the serpentine electrode is as follows Figure 1 As shown, the curved serpentine design maximizes the heat generation area when current passes through, ensuring uniform heating of the sensitive material coating of the sensor.

[0030] The sensitive material coating is a sensitive material that is evenly coated on the detection-heating electrode by spin coating or sputtering technology, and is used to detect the adsorption and desorption process of gas molecules. The sensitive material is a gas-sensitive material. Sensitive materials can use common gas-sensitive materials such as tin oxide (SnO2), zinc oxide (ZnO) or tungsten oxide (WO3). These materials have good adsorption properties for gas molecules and can achieve rapid desorption reactions at high temperatures. The embodiment of the present invention is made by coating tin oxide, zinc oxide or tungsten oxide on the surface of the detection-heating electrode by spin coating or sputtering technology.

[0031] like Figure 2 As shown, a method for assembling a gas sensor with a heating desorption function comprises the following steps: Step 1. Clean and dry the substrate to ensure it is dust-free and pollution-free; Step 2. Then, a serpentine detection-heating electrode is fabricated on the substrate by sputtering or evaporation process; Step 3. Use spin coating or sputtering technology to evenly coat the sensitive material on the electrode surface to complete the assembly of the gas sensor; Step 4. Package the gas sensor to ensure stability and reliability during use.

[0032] The working principle of the embodiment of the present invention is as follows: when the sensor is in normal working state, electrode No. 3 is kept grounded, and the adsorption reaction of gas molecules on the sensitive material is detected by measuring the resistance change between electrode No. 1 and electrode No. 3, thereby realizing the gas detection function. After the detection is completed, in order to desorb the sensitive material, electrode No. 1 is grounded, and a certain voltage is applied to electrode No. 2, and the heating effect of the current passing through the electrodes is used to heat the coating of the sensitive material, promote the desorption of gas molecules, and thus restore the detection performance of the sensor.

[0033] A method for using a gas sensor with a heating desorption function comprises the following steps: During the gas detection process, the gas sensor is in normal working condition, electrode 3 is kept grounded, and the adsorption of gas molecules is determined by measuring the resistance change between electrode 1 and electrode 3; when the sensitive material needs to be desorbed, electrode 1 is grounded, and voltage is applied to electrode 2, and the heat generated by the current is used to heat the sensitive material to desorb the gas molecules.

[0034] The above is a detailed introduction to a gas sensor with a heating desorption function provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A gas sensor with heating desorption function, characterized in that: From bottom to top they are: A substrate, which is used to support the entire gas sensor and has high thermal conductivity; Detection-heating electrode: including a serpentine electrode and an inverted F-type electrode; the serpentine electrode is arranged near and along the inverted F-type electrode; the head of the serpentine electrode is electrode No. 1, and the tail is electrode No. 2; the head of the inverted F-type electrode is electrode No. 3; the electrode No. 1 is grounded under normal working conditions of the gas sensor; the detection-heating electrode is made of conductive material through sputtering or evaporation process, and is used as a detection electrode and as a heating electrode for desorption when needed; The sensitive material coating is a sensitive material uniformly coated on the detection-heating electrode by spin coating or sputtering technology, and is used to detect the adsorption and desorption process of gas molecules; the sensitive material is a gas-sensitive material.

2. The gas sensor with heating desorption function according to claim 1, characterized in that: The inverted F-shaped electrode is also provided with a plurality of integrally formed transverse electrodes; the serpentine electrode is arranged along the inverted F-shaped electrode and the transverse electrodes.

3. The gas sensor with heating desorption function according to claim 1, characterized in that: The substrate is made of ceramic material with high thermal conductivity.

4. The gas sensor with heating desorption function according to claim 1, characterized in that: The substrate is made of aluminum oxide.

5. The gas sensor with heating desorption function according to claim 1, characterized in that: The detection-heating electrode is made of a metal material with good electrical conductivity and high temperature resistance through a sputtering or evaporation process.

6. The gas sensor with heating desorption function according to claim 1, characterized in that: The detection-heating electrode is made of platinum, gold or silver alloy by sputtering or evaporation process.

7. The gas sensor with heating desorption function according to claim 1, characterized in that: The sensitive material is made of tin oxide, zinc oxide or tungsten oxide and is coated on the surface of the detection-heating electrode by spin coating or sputtering technology.

8. A method for assembling a gas sensor with a heating desorption function, comprising the following steps: Step 1. Clean and dry the substrate to ensure it is dust-free and pollution-free; Step 2. Fabricate a serpentine detection-heating electrode on the substrate by sputtering or evaporation process; Step 3. Use spin coating or sputtering technology to evenly coat the sensitive material on the electrode surface to complete the assembly of the gas sensor; Step 4. Package the gas sensor to ensure stability and reliability during use.

9. The method for using a gas sensor with heating desorption function according to any one of claims 1 to 7, comprising the following steps: During the gas detection process, the gas sensor is in normal working condition, electrode No. 3 is kept grounded, and the adsorption of gas molecules is determined by measuring the resistance change between electrode No. 1 and electrode No. 3; when the sensitive material needs to be desorbed, electrode No. 1 is grounded, and voltage is applied to electrode No.

2. The heat generated by the current is used to heat the sensitive material to desorb the gas molecules.

Images