Method for manufacturing a temperature and humidity sensor

Abstract

The application discloses a manufacturing method of a temperature and humidity sensor. The whole surface of a skeleton disc, including the surface of a deep groove, is covered with a humidity sensitive film with a predetermined thickness to obtain a humidity sensitive resistance. The humidity sensitive resistance, a temperature sensor and an MCU are electrically connected. The MCU measures the resistance and the temperature. A standard database of temperature T-humidity sensitive resistance R-humidity H is formed, and the standard database is written into the ROM of the MCU to obtain a final temperature and humidity sensor.

Description

Technical Field

[0001] This invention relates to a method for manufacturing a temperature and humidity sensor, specifically a method for manufacturing a fast-response temperature and humidity sensor, and is a further improvement on the prior application CN202111504775.9. Background Technology

[0002] Studies have found that humidity sensors are not only sensitive to ambient humidity but also highly sensitive to temperature, with a temperature coefficient typically ranging from 0.2% to 0.8%RH / ℃. Furthermore, the temperature coefficient of some humidity sensors varies under different relative humidity levels. The operating temperature range of the humidity sensor is also an important parameter. Accuracy and long-term stability are also crucial. The accuracy of a humidity sensor should reach ±2% to ±5%RH; anything below this level is difficult to use as a measuring instrument. Achieving an accuracy of ±2% to ±3%RH is quite challenging. Typically, the characteristics given in industry data are measured at room temperature (20℃±10℃) and in clean gas. At different temperatures, humidity sensors often provide different ambient humidity values; the greater the temperature drift, the greater the deviation in the humidity measurement. Our prior application CN202111504775.9 does not solve the above-mentioned technical problems. The inventors have found that the technical solution of our prior application CN202111504775.9 is not suitable for humidity measurement in environments with large temperature variations, and the accuracy of humidity measurement needs improvement. Summary of the Invention

[0003] To solve the above-mentioned technical problems, the present invention provides a fast-response temperature and humidity sensor, which is a further improvement on the prior application CN202111504775.9. The purpose of the present invention is to provide a temperature coefficient calibrated, highly sensitive, and fast-response humidity sensor.

[0004] The technical solution is as follows:

[0005] A method for manufacturing a temperature and humidity sensor, wherein the sensor is a fast-response type, characterized in that the manufacturing method includes the following steps:

[0006] S1. The nano-humidity-sensitive material is added to a solvent and stirred until homogeneous to obtain a precursor solution of a predetermined concentration; the resistivity of the humidity-sensitive material is sensitive to ambient humidity.

[0007] S2. Prepare a frame tray, which is made of non-humidity-sensitive insulating material, and has multiple deep groove-type air channels evenly arranged around its perimeter; the air channels are used to shorten the moisture absorption response time and dehumidification response time of the humidity-sensitive material; the frame tray is provided with a socket, into which a temperature sensor is inserted and fixed.

[0008] Preferably, the temperature and humidity sensor includes a humidity-sensitive material and a skeleton disk; the skeleton disk has multiple "T"-shaped skeletons arranged radially and evenly around its circumference, and the humidity-sensitive material completely covers the multiple "T"-shaped skeletons. The space between each pair of adjacent "T"-shaped skeletons forms an airflow channel, which is used to shorten the moisture absorption response time and desiccation response time of the humidity-sensitive material.

[0009] The skeleton disk has an upper surface and a lower surface arranged relatively parallel to each other. The upper and lower surfaces of the skeleton disk are both made of conductive material, which serve as the upper and lower electrodes of the high-sensitivity humidity sensor, respectively. The part of the skeleton disk other than the upper and lower surfaces is made of non-humidity-sensitive insulating material. After the humidity-sensitive material is covered, it is led out and connected to the upper and lower electrodes, respectively. The resistivity of the humidity-sensitive material is sensitive to the ambient humidity. The humidity-sensitive material located between the upper and lower electrodes constitutes a humidity-sensitive resistor.

[0010] S3. Prepare two metal plates and fix them on the upper and lower surfaces of the frame disk, respectively, to serve as the upper and lower electrodes of the temperature and humidity sensor; then weld a certain length of metal wires onto the two metal plates.

[0011] In step S3, the shape and size of the metal sheet are the same as the shape and size of the cross-section of the skeleton disk.

[0012] S4. Using the precursor solution obtained in step S1, cover the entire surface of the skeleton disk obtained in step S3, including the surface of the deep groove, with a humidity-sensitive film of a predetermined thickness to obtain a humidity-sensitive resistor.

[0013] S5. Remove the humidity-sensitive film from the surface of the metal wire, and electrically connect the humidity-sensitive resistor, temperature sensor, and MCU; the MCU measures the resistance and temperature; the MCU is a microcontroller unit (MCU) with on-chip ROM.

[0014] A microcontroller unit (MCU), also known as a single-chip microcomputer or microcontroller, is a chip-level computer that integrates a central processing unit (CPU) with a reduced frequency and specifications, and peripheral interfaces such as memory, timer, USB, A / D converter, UART, PLC, DMA, and even LCD driver circuitry onto a single chip.

[0015] S6. A standard database of temperature T, humidity-sensitive resistor R, and humidity H is formed, and written into the ROM of the MCU to obtain the final temperature and humidity sensor. The specific implementation is as follows:

[0016] Multiple test chambers with different humidity levels are configured, and the resistance values ​​of the humidity-sensitive resistors in different known humidity environments are tested at different temperatures. The corresponding humidity H, temperature T, and humidity-sensitive resistor R for each record are stored in the ROM of the MCU to form a standard database. The standard database includes multiple humidity-sensitive resistor R-humidity H curves (R(H)T curves) of the fast-response temperature and humidity sensor at different temperatures T. Each R(H)T curve records the humidity-sensitive resistor R corresponding to different humidity values ​​H. When using the temperature and humidity sensor, the MCU performs temperature correction on the humidity measurement values.

[0017] Preferably, the metal wire described in step S3 has an insulating outer sheath. In step S5, wire strippers are used to remove a certain length of the insulating outer sheath from the end of the metal wire, making it easier for the metal wire to be soldered and electrically connected to the MCU.

[0018] Preferably, the humidity-sensitive material is SnO2:TiO2 composite nanomaterial.

[0019] This invention is a further improvement upon prior application CN202111504775.9, and naturally possesses the advantages of CN202111504775.9: the deep-groove airflow channel allows the humidity-sensitive material to have more sufficient contact with the air, and accelerates the desorption of adsorbed water molecules in the humidity-sensitive material through the airflow channel. This can be used to shorten the moisture absorption response time and desiccation response time of the humidity-sensitive material, greatly improving the response speed of the humidity sensor. When the outer shell of the composite nanoparticles or composite nanowires comes into contact with water, it will expand, increasing the distance between the contacting composite nanoparticles or composite nanowires, thereby reducing the conductivity of the humidity-sensitive material. By using composite nanoparticles or composite nanowires, their specific surface area is increased, and the outer shell is fully exposed to the atmospheric environment, thereby improving its response speed and sensitivity, and increasing the desorption rate of water molecules.

[0020] Meanwhile, this invention also overcomes some shortcomings of the prior application CN202111504775.9, namely, by setting a temperature sensor in the fast-response temperature and humidity sensor, the temperature sensor is used to measure the ambient temperature where the temperature and humidity sensor is located, and the microcontroller unit (MCU) performs temperature compensation for the humidity measurement value, so that the fast-response temperature and humidity sensor has fast response characteristics, and the temperature stability and accuracy of humidity measurement are greatly improved, overcoming the disadvantage of humidity measurement value drift with temperature.

[0021] The inventors have now described in detail the working principle, technical solution, and technical effects of this invention. Any content not described in detail herein is prior art known to those skilled in the art. Attached Figure Description

[0022] Figure 1 The overall shape is a cylindrical skeletal disc;

[0023] Figure 2 The overall shape is presented as a top view of a square columnar skeleton disk. Detailed Implementation

[0024] The technical solution of the present invention will be described in detail below with reference to examples.

[0025] A fast-response temperature and humidity sensor includes a humidity-sensitive material and a frame disk, a temperature sensor, and an MCU (Micro Controller Unit) with on-chip ROM. The frame disk has multiple deep-groove air channels evenly distributed around its perimeter and is made of a non-humidity-sensitive insulating material. Metal circular plates are disposed on the relatively parallel upper and lower surfaces of the frame disk, serving as the upper and lower electrodes of the temperature and humidity sensor, respectively. After the humidity-sensitive material is applied, it is electrically connected to the upper and lower electrodes. The humidity-sensitive material located between the upper and lower electrodes constitutes a humidity-sensitive resistor, which is electrically connected to the MCU for resistance measurement.

[0026] The overall shape of the skeleton disk can be any one of cylindrical, square, or prismatic. Preferably, the cylindrical skeleton disk is cylindrical. Preferably, the circumference of the cylindrical skeleton disk is provided with multiple radially evenly distributed "T"-shaped skeletons. Preferably, the humidity-sensitive material completely covers the multiple "T"-shaped skeletons, and the space between each two adjacent "T"-shaped skeletons forms a deep groove-type airflow channel. The airflow channel is used to shorten the moisture absorption response time and desiccation response time of the humidity-sensitive material.

[0027] A method for manufacturing a temperature and humidity sensor, wherein the sensor is a fast-response type, characterized in that the manufacturing method includes the following steps:

[0028] S1. Add the nano-humidity-sensitive material to a solvent and stir until homogeneous to obtain a precursor solution of a predetermined concentration; the resistivity of the humidity-sensitive material is sensitive to ambient humidity; preferably, the humidity-sensitive material is a SnO2:TiO2 composite nanomaterial.

[0029] S2. Prepare a frame tray, which is made of non-humidity-sensitive insulating material, and has multiple deep groove-type air channels evenly arranged around its perimeter; the air channels are used to shorten the moisture absorption response time and dehumidification response time of the humidity-sensitive material; the frame tray is provided with a socket, into which a temperature sensor is inserted and fixed; the socket is used to fix the temperature sensor, which is electrically connected to the microcontroller unit, and the temperature sensor is used to measure the ambient temperature of the temperature and humidity sensor, and the MCU performs temperature correction on the humidity measurement value.

[0030] S3. Prepare two metal sheets and fix them on the upper and lower surfaces of the skeleton disk, respectively, as the upper and lower electrodes of the temperature and humidity sensor; then weld a certain length of metal wires onto the two metal sheets; in step S3, the shape and size of the metal sheets are the same as the shape and size of the cross-section of the skeleton disk.

[0031] S4. Using the precursor solution obtained in step S1, cover the entire surface of the skeleton disk obtained in step S3, including the surface of the deep groove, with a humidity-sensitive film of a predetermined thickness to obtain a humidity-sensitive resistor.

[0032] Step S4 is implemented as follows:

[0033] The skeleton disk with welded metal wires and two metal sheets obtained in step S3 is immersed in the precursor solution obtained in step S1, then removed, dried, and sintered, so that the humidity-sensitive material is solidified on the entire surface of the skeleton disk to form a humidity-sensitive film. The skeleton disk is immersed in the precursor solution obtained in step S1 again, removed, dried, and sintered. This process is repeated a predetermined number of times, the predetermined number of times depending on the thickness of the humidity-sensitive film to be obtained. The upper electrode, lower electrode, and humidity-sensitive material constitute a humidity-sensitive resistor.

[0034] S5. Remove the humidity-sensitive film from the surface of the metal wire, and electrically connect the humidity-sensitive resistor, temperature sensor, and MCU; the MCU measures the resistance and temperature; the MCU is a microcontroller unit (MCU) with on-chip ROM.

[0035] MCUs can be categorized into two types based on their memory type: those without on-chip ROM and those with on-chip ROM. Chips without on-chip ROM require an external EPROM for operation. Chips with on-chip ROM are further divided into on-chip EPROM, on-chip EEPROM, mask-based on-chip ROM, and on-chip FLASH types. Some companies also offer chips with on-chip one-time programmable ROM (OTP). More user-friendly MCU designs integrate both FLASH and EEPROM, both non-volatile memories.

[0036] In this invention, preferably, an MCU with on-chip ROM is used.

[0037] S6. Form a standard database of temperature T-humidity sensitive resistor R-humidity H, write the standard database into the ROM of the MCU to obtain the final temperature and humidity sensor.

[0038] As an optional implementation, the MCU communicates with the temperature sensor via I / O. 2 C bus connection. I 2 The C bus occupies two MCU input / output lines, and communication between them is entirely software-based. The temperature sensor's address can be set via two address pins, allowing one I / O pin to be used for... 2 Up to eight such sensors can be connected simultaneously on the C-bus. In this solution, the 7-bit address of the sensor is set to 1001000. When the MCU needs to access the sensor, it first sends an 8-bit register pointer, and then sends the sensor's address (7-bit address, with the lower bit being the WR signal). The sensor has three registers available to the MCU; the 8-bit register pointer is used to determine which register the MCU should use. In this invention, one implementation involves the program continuously updating the sensor's configuration register, which causes the sensor to operate in single-step mode, measuring the temperature once per update.

[0039] Preferably, after step S4 and before step S5, the method further includes coating the upper and lower surfaces of the cylindrical skeleton disk with a conductive paste to reliably connect the humidity-sensitive material with the upper and lower electrodes.

[0040] Step S6 is implemented as follows:

[0041] Multiple test chambers with different humidity levels are configured to test the resistance values ​​of humidity-sensitive resistors in different known humidity environments at different temperatures. The corresponding humidity (H), temperature (T), and humidity-sensitive resistor (R) values ​​for each record are stored in the MCU's ROM, forming a standard database. This standard database includes multiple humidity-sensitive resistor (R)-humidity (H) curves (R(H)T curves) of the fast-response temperature and humidity sensor at different temperatures (T). Each R(H)T curve records the humidity-sensitive resistor (R) corresponding to different humidity values ​​(H). When using the temperature and humidity sensor, the MCU performs temperature calibration of the humidity measurement values. To write the standard database into the ROM (such as EPROM, EEPROM, or FLASH), the pre-calibrated R(H)T curve data needs to be written into the ROM via a series of instructions.

[0042] In this invention, in order to achieve temperature correction of humidity measurement values ​​by the MCU, the on-chip ROM of the MCU stores a standard database. The standard database includes multiple humidity-sensitive resistance R-humidity H curves of the fast-response temperature and humidity sensor at different temperatures T, i.e., R(H). T Curves, each R(H) T The curve records the humidity-sensitive resistor R corresponding to different humidity values ​​H.

[0043] The pre-prepared temperature and humidity sensor is placed in the test chamber. The test chamber is evacuated and the gas inside is configured to have a humidity of 1RH%. The temperature of the test chamber is controlled, and the resistance value of the humidity-sensitive resistor is measured at 1℃, 2℃, 3℃...84℃, 85℃, with a temperature interval of 1℃. The resistance value measured at each temperature, along with the 1RH% humidity value, is stored in the standard database.

[0044] The test chamber was evacuated, and the gas inside was configured to have a humidity of 2RH%. The temperature of the test chamber was controlled, and the resistance value of the humidity-sensitive resistor was measured at 1℃, 2℃, 3℃...84℃, 85℃, with a temperature interval of 1℃. The resistance value measured at each temperature, together with the 2RH% humidity value, was stored in the standard database.

[0045] The test chamber was evacuated, and the gas inside was configured to have a humidity of 3RH%. The temperature of the test chamber was controlled, and the resistance value of the humidity-sensitive resistor was measured at 1℃, 2℃, 3℃...84℃, 85℃, with a temperature interval of 1℃. The resistance value measured at each temperature, together with the 3RH% humidity value, was stored in the standard database.

[0046] ...

[0047] The test chamber was evacuated, and the gas inside was configured to have a humidity of 80% RH. The temperature of the test chamber was controlled, and the resistance value of the humidity-sensitive resistor was measured at 1℃, 2℃, 3℃...84℃, 85℃, with a temperature interval of 1℃. The resistance value measured at each temperature, along with the 3% RH humidity value, was stored in the standard database.

[0048] The test chamber was evacuated, and the gas inside was configured to have a humidity of 81% RH. The temperature of the test chamber was controlled, and the resistance value of the humidity-sensitive resistor was measured at 1℃, 2℃, 3℃...84℃, 85℃, with a temperature interval of 1℃. The resistance value measured at each temperature, along with the 3% RH humidity value, was stored in the standard database.

[0049] ...

[0050] This process is repeated, increasing by 1% RH, i.e., at 1% RH intervals, until 90% RH is reached.

[0051] Optionally, the temperature interval is 1℃, 0.5℃, 0.2℃, or 0.1℃, and the humidity interval is 1%RH, 0.5%RH, 0.2%RH, or 0.1%RH. That is, the standard database includes multiple humidity-sensitive resistance R-humidity H curves of the aforementioned fast-response temperature and humidity sensor at different temperatures T, with temperature intervals of 1℃, 0.5℃, 0.2℃, or 0.1℃, and humidity intervals of 1%RH, 0.5%RH, 0.2%RH, or 0.1%RH.

[0052] The MCU looks up the corresponding humidity value H in the standard database based on the measured temperature value T and resistance value R. Specifically, the MCU finds the value point in the standard database that is closest to the measured temperature value T and resistance value R, and outputs the humidity value H of the closest value point as the ambient humidity measurement value.

[0053] Clearly, the MCU looks up the corresponding humidity value H in a standard database based on the measured temperature value T and resistance value R. The smaller the temperature and humidity intervals in the standard database, the more accurate the output humidity value H. Those skilled in the art will readily understand that for the final measured environmental humidity value to have sufficient precision and accuracy, the temperature and humidity intervals in the standard database must be sufficiently small, and the R(H) interval in the standard database must be... T The more curves and the denser the data points, the easier it is to find a closer and more accurate humidity value.

[0054] Furthermore, those skilled in the art will readily recognize that to obtain sufficiently accurate and precise environmental humidity values, an MCU with a large enough ROM capacity should be selected. This may result in a smaller selection of MCU models and an increase in MCU prices.

[0055] Of course, to improve the flexibility of sensor manufacturing, the MCU with on-chip ROM can be replaced with an MCU without on-chip ROM and an external ROM, such as EPROM, EEPROM or FLASH.

[0056] The humidity-sensitive material is a humidity-sensitive material that covers multiple "T"-shaped skeletons on a cylindrical skeleton disk. The space between every two adjacent "T"-shaped skeletons simultaneously forms a limiting groove and an air flow channel for the humidity-sensitive material. After the humidity-sensitive material is covered, there is still space left that facilitates air circulation, i.e., an air flow channel. The air flow channel is used to shorten the moisture absorption response time and desiccation response time of the humidity-sensitive material.

[0057] Preferably, step S1 specifically comprises:

[0058] Using tin chloride pentahydrate (SnCl4·5H2O) as the starting material, SnCl4·5H2O was dissolved in ethanol and stirred in a magnetic stirrer. Tetraisopropoxide titanium (Ti(C3H7O)4) was added dropwise until a clear solution was obtained. Then, the solution was refluxed for 3 hours to obtain the precursor solution.

[0059] Preferably, after heat reflux, appropriate amounts of deionized water, viscosity modifier and dispersant are added as needed, and the resulting colloidal solution is used as a precursor solution;

[0060] Preferably, the precursor solution is then aged for another 10 days;

[0061] Preferably, in the precursor solution obtained in the final configuration, the Sn:Ti molar ratio is 5:1 to 8:1.

[0062] As one specific implementation method, see Figure 1 A humidity sensor includes a humidity-sensitive material and a skeleton disk; the skeleton disk has multiple "T"-shaped skeletons arranged radially and evenly around its circumference, and the humidity-sensitive material covers the multiple "T"-shaped skeletons. The space between each pair of adjacent "T"-shaped skeletons simultaneously forms a limiting groove and an air flow channel. After the humidity-sensitive material is covered, there is still space left that facilitates air circulation, i.e., an air flow channel. The air flow channel is used to shorten the moisture absorption response time and desiccation response time of the humidity-sensitive material.

[0063] The skeleton disk has an upper surface and a lower surface arranged relatively parallel to each other. An upper electrode and a lower electrode are respectively provided on the upper surface and the lower surface. After the humidity-sensitive material is covered, it is led out and connected to the upper electrode and the lower electrode respectively. The upper electrode and the lower electrode are not shown in the figure. The resistivity of the humidity-sensitive material is sensitive to the ambient humidity. The humidity-sensitive material located between the upper electrode and the lower electrode constitutes a humidity-sensitive resistor.

[0064] Figure 2 The image shows a top view of the overall shape of the present invention, which is a square columnar skeleton disk, excluding the moisture-sensitive material.

[0065] For humidity-sensitive materials, any other known materials with humidity-sensitive properties can be selected.

[0066] In a preferred embodiment, when the humidity-sensitive material is led out and connected to the upper and lower electrodes respectively, it includes multiple lead-out taps;

[0067] Preferably, the humidity-sensitive material is coated with a conductive paste on the upper and lower surfaces near the skeleton disk, and the conductive paste is used to connect to the upper and lower electrodes, respectively. It is worth noting that the skeleton disk is made of a non-humidity-sensitive insulating material.

[0068] After coating with conductive paste, a low-temperature drying and curing process should be performed.

[0069] Preferably, the upper electrode and the lower electrode are two metal disks, and a fixing screw hole is provided at the center of the disk for tightening and fixing the lead wire.

[0070] It should be noted that the directional terms mentioned in the embodiments, such as "up," "down," "front," "back," "left," and "right," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of the present invention. Throughout the accompanying drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted where they may cause confusion in understanding the present invention.

[0071] Furthermore, the shapes and dimensions of the components in the figures do not reflect actual size and proportion, but are only illustrative of embodiments of the present invention. Additionally, any reference signs placed between parentheses in the claims should not be construed as limiting the claims.

[0072] Furthermore, unless specifically described or required to occur in a specific order, the order of the above steps is not limited to those listed above and can be varied or rearranged according to the desired design. Moreover, the above embodiments can be used in combination with each other or with other embodiments based on design and reliability considerations; that is, technical features from different embodiments can be freely combined to form more embodiments.

[0073] Similarly, it should be understood that, in order to simplify the invention and aid in understanding one or more of the various aspects of the invention, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this inventive approach should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single embodiment of the foregoing invention. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, wherein each claim itself is a separate embodiment of the invention.

[0074] It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method of manufacturing a temperature and humidity sensor, the sensor being of the fast response type, characterized in that: The manufacturing method comprises the following steps: S1. The nano-humidity sensitive material is added into a solvent and stirred uniformly to obtain a precursor solution with a predetermined concentration; the resistivity of the humidity sensitive material is sensitive to the ambient humidity; S2. A skeleton plate is prepared, the skeleton plate is made of non-humidity sensitive insulating material, and a plurality of deep groove air channels are uniformly arranged around the skeleton plate; a plurality of "T" shaped skeletons are uniformly distributed in a radial manner around the skeleton plate, the humidity sensitive material completely covers the plurality of "T" shaped skeletons, the space between every two adjacent "T" shaped skeletons forms an air channel, and the air channel is used to shorten the humidity absorption response time and the humidity desorption response time of the humidity sensitive material; the skeleton plate is provided with a jack, and a temperature sensor is inserted into the jack and fixed; S3. Two metal sheets are prepared, and the two metal sheets are respectively fixed on the upper surface and the lower surface of the skeleton plate to serve as the upper electrode and the lower electrode of the temperature and humidity sensor respectively; then a certain length of metal wire is welded on each of the two metal sheets; S4. The precursor solution obtained in step S1 is used to cover the entire surface of the skeleton plate obtained in step S3 including the surface of the deep groove to obtain a humidity sensitive film with a predetermined thickness, so as to obtain a humidity sensitive resistor; S5. The humidity sensitive film on the surface of the metal wire is removed, and the humidity sensitive resistor, the temperature sensor and the MCU are electrically connected; the resistance and the temperature are measured by the MCU; the MCU is a MCU with an on-chip ROM type; S6. A standard database of temperature T-humidity sensitive resistor R-humidity H is formed, the standard database is written into the ROM of the MCU, and a final temperature and humidity sensor is obtained.

2. The method of claim 1, wherein: In step S3, the shape and size of the metal sheet are the same as the shape and size of the cross section of the skeleton plate.

3. The method of claim 1 or 2, wherein: The step S1 is specifically: SnCl4·5H2O is used as a starting material, SnCl4·5H2O is dissolved in ethanol, stirring is performed in a magnetic stirrer, and Ti(C3H7O)4 is added dropwise until a transparent solution is obtained, then hot reflux is performed for 3 hours to obtain a precursor solution; After hot reflux, a proper amount of deionized water, a viscosity regulator and a dispersant are added according to needs, and the obtained colloidal solution is used as a precursor solution; The precursor solution is placed for aging for 10 days; In the finally configured precursor solution, the molar ratio of Sn:Ti is 5:1~8:

1.

4. The method according to any one of claims 1 to 3, characterized in that: The metal wire in step S3 has an insulating sheath, and in step S5, the insulating sheath of a certain length at the end of the metal wire is removed by using a wire stripper, so that the metal wire is convenient for welding and electrical connection to the MCU.

5. The method according to any one of claims 1 to 3, wherein: Step S4 is specifically implemented as follows: The framework disc welded with the metal wire and provided with the two metal sheets obtained in step S3 is immersed in the precursor solution obtained in step S1, and then taken out and dried, sintered, so that the humidity-sensitive material is solidified on the whole surface of the framework disc to form a humidity-sensitive film. The framework disc is immersed in the precursor solution obtained in step S1 again, taken out and dried, sintered, and the process is repeated for a predetermined number of times, which is determined by the thickness of the humidity-sensitive film to be obtained; the humidity-sensitive resistance is composed of an upper electrode, a lower electrode and a humidity-sensitive material.

6. The method of any one of claims 1-3, wherein: Step S6 is specifically implemented as follows: Multiple test chambers with different humidity levels are configured, and the resistance values ​​of the humidity-sensitive resistors are tested at different temperatures in different known humidity environments. The corresponding humidity H, temperature T, and humidity-sensitive resistor R for each record are stored in the MCU's ROM to form a standard database. The standard database includes multiple humidity-sensitive resistor R-humidity H curves of the fast-response temperature and humidity sensor at different temperatures T, i.e., R(H). T The curve, each R(H) T The curve records the humidity-sensitive resistor R corresponding to different humidity values ​​H; when using a temperature and humidity sensor, the MCU performs temperature correction on the humidity measurement value.

7. The method of claim 6, wherein: The temperature and humidity sensor prepared in advance is placed in a test cavity, the test cavity is vacuumed, and then the gas therein is configured to be 1 RH% humidity. The temperature of the test cavity is controlled, and the resistance value of the humidity-sensitive resistance is measured at 1℃, 2℃, 3℃, …, 85℃, that is, the temperature interval is 1℃. The resistance value measured at each temperature is stored in the standard database together with the 1 RH% humidity value. The test cavity is vacuumed, and then the gas therein is configured to be 2 RH% humidity. The temperature of the test cavity is controlled, and the resistance value of the humidity-sensitive resistance is measured at 1℃, 2℃, 3℃, …, 85℃, that is, the temperature interval is 1℃. The resistance value measured at each temperature is stored in the standard database together with the 2 RH% humidity value. The test cavity is vacuumed, and then the gas therein is configured to be 3 RH% humidity. The temperature of the test cavity is controlled, and the resistance value of the humidity-sensitive resistance is measured at 1℃, 2℃, 3℃, …, 85℃, that is, the temperature interval is 1℃. The resistance value measured at each temperature is stored in the standard database together with the 3 RH% humidity value. …, and so on, with the humidity increasing by 1 RH% each time, that is, the humidity interval is 1 RH%, until 90 RH%.

8. The method of claim 7, wherein: The temperature interval is 1℃ or 0.5℃ or 0.2℃ or 0.1℃, and the humidity interval is 1 RH% or 0.5 RH% or 0.2 RH% or 0.1 RH%.

9. The method of any one of claims 1-5, wherein: The overall shape of the framework disc is any one of a cylindrical shape, a square column shape, a rectangular column shape, or a prism shape.

10. The method of claim 9, wherein: The overall shape of the framework disc is a cylindrical shape. The circumference of the cylindrical framework disc is provided with a plurality of "T" shaped frameworks uniformly distributed in a radial manner. The humidity-sensitive material completely covers the plurality of "T" shaped frameworks. The space between every two adjacent "T" shaped frameworks constitutes a deep groove air flow channel. The air flow channel is used to shorten the hygroscopic response time and the dehumidification response time of the humidity-sensitive material. After step S4 and before step S5, the upper surface and the lower surface of the cylindrical framework disc are coated with conductive paste, so that the humidity-sensitive material is reliably electrically connected with the upper electrode and the lower electrode.

11. The method of claim 1, wherein: The on-chip ROM type MCU is selected from any one of the following: on-chip one-time programmable ROM type MCU, on-chip EPROM type MCU, on-chip EEPROM type MCU, on-chip mask ROM type MCU, on-chip FLASH type MCU, and MCU integrated with both FLASH and EEPROM; Or, the above-mentioned MCU with on-chip ROM is replaced by MCU without on-chip ROM and is externally connected with EPROM or EEPROM or FLASH.

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