Bidirectional stereoscopic heating type humidity sensor and device with humidity collection function

Abstract

The present application relates to the technical field of humidity sensor, especially to a bidirectional three-dimensional heating type humidity sensor and equipment with humidity collection function, the bidirectional three-dimensional heating type humidity sensor comprises a substrate, a lower heating circuit, a humidity sensing layer and an upper heating circuit, the substrate, the lower heating circuit, the humidity sensing layer and the upper heating circuit are sequentially stacked, or the lower heating circuit, the substrate, the humidity sensing layer and the upper heating circuit are sequentially stacked. The upper heating circuit and the lower heating circuit can realize direct and bidirectional heating of the humidity sensing layer in the vertical direction, the heating efficiency of the traditional heating type humidity sensor is doubled, and the temperature after heating is consistent with the surface temperature of the humidity sensing layer, which greatly reduces the temperature error and improves the humidity measurement accuracy.

Description

Technical Field

[0001] This invention relates to the field of humidity sensor technology, and in particular to a bidirectional three-dimensional heating humidity sensor and a device with humidity acquisition function. Background Technology

[0002] Humidity measurement is a crucial requirement in most meteorological fields, typically involving placing humidity sensors in exposed environments, directly in contact with the air. Currently, polymer capacitive humidity sensors are commonly used. These sensors utilize a metal electrode and a humidity-sensitive material as a moisture-sensing medium layer on a substrate surface, forming a humidity-sensitive capacitor structure. This structure offers advantages such as a wide humidity range, good linearity, and fast response. However, in low-temperature humidity measurement applications, the exposed chip can experience frost or ice formation, directly impacting measurement accuracy. Therefore, heated capacitive humidity sensors are now commonly used. Heating the humidity-sensitive capacitor removes surface frost, improving measurement accuracy. However, many commercially available humidity sensors achieve heating through external heating resistors or heating circuits around the humidity-sensitive capacitor chip. These structures suffer from indirect heating, low heating efficiency, and inaccuracies in the actual temperature measurement of the chip surface, directly leading to measurement errors and reduced accuracy. Summary of the Invention

[0003] To address the problems of indirect heating, low heating efficiency, and deviations in the actual temperature measurement of the chip surface in capacitive heating humidity sensors.

[0004] The technical solution of the bidirectional three-dimensional heating humidity sensor of the present invention is as follows:

[0005] It includes a substrate, a lower heating circuit, a moisture-sensing layer, and an upper heating circuit, wherein the substrate, the lower heating circuit, the moisture-sensing layer, and the upper heating circuit are stacked sequentially, or the lower heating circuit, the substrate, the moisture-sensing layer, and the upper heating circuit are stacked sequentially.

[0006] The beneficial effects of the bidirectional three-dimensional heating humidity sensor of the present invention are as follows:

[0007] By utilizing upper and lower heating circuits, direct, bidirectional heating of the humidity-sensing layer in the vertical direction can be achieved, doubling the heating efficiency compared to traditional heating humidity sensors. Furthermore, the heated temperature is consistent with the surface temperature of the humidity-sensing layer, greatly reducing temperature errors and thus improving humidity measurement accuracy.

[0008] Based on the above solution, the bidirectional three-dimensional heating humidity sensor of the present invention can be further improved as follows.

[0009] Furthermore, it also includes a lower electrode of a humidity-sensitive capacitor, which is disposed between the humidity-sensitive layer and the substrate.

[0010] Furthermore, the humidity-sensitive capacitor lower electrode includes a first local humidity-sensitive capacitor lower electrode and a second local humidity-sensitive capacitor lower electrode that are separated from each other, and a capacitive humidity sensing element lower electrode metal pad is respectively disposed on the first local humidity-sensitive capacitor lower electrode and the second local humidity-sensitive capacitor lower electrode.

[0011] Furthermore, it also includes a first local humidity-sensitive capacitor lower electrode metal substrate layer and a second local humidity-sensitive capacitor lower electrode metal substrate layer, wherein the first local humidity-sensitive capacitor lower electrode is disposed on the first local humidity-sensitive capacitor lower electrode metal substrate layer, and the second local humidity-sensitive capacitor lower electrode is disposed on the second local humidity-sensitive capacitor lower electrode metal substrate layer.

[0012] Furthermore, it also includes a lower heating circuit substrate layer embedded in the substrate, wherein the lower heating circuit is disposed on the lower heating circuit substrate layer and the lower heating circuit is embedded in the substrate.

[0013] Furthermore, it also includes a dielectric layer disposed between the lower electrode of the humidity-sensitive capacitor and the substrate.

[0014] Furthermore, the dielectric layer is applied over the lower heating circuit.

[0015] Furthermore, the upper heating circuit is provided with two upper heating circuit metal pads.

[0016] Furthermore, the lower heating circuit is provided with two lower heating circuit metal pads.

[0017] The present invention provides a device with humidity acquisition function, including a bidirectional three-dimensional heating humidity sensor as described in any of the preceding claims. Attached Figure Description

[0018] Figure 1 This is one of the exploded views of a bidirectional three-dimensional heating humidity sensor according to an embodiment of the present invention;

[0019] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of a bidirectional three-dimensional heating humidity sensor;

[0020] Figure 3 This is a second exploded view of a bidirectional three-dimensional heating humidity sensor according to an embodiment of the present invention;

[0021] Figure 4 for Figure 3 A schematic diagram of the cross-sectional structure of a bidirectional three-dimensional heating humidity sensor;

[0022] Figure 5 This is the third exploded view of a bidirectional three-dimensional heating humidity sensor according to an embodiment of the present invention;

[0023] Figure 6 for Figure 5 A schematic diagram of the cross-sectional structure of a bidirectional three-dimensional heating humidity sensor;

[0024] Figure 7 for Figure 5 A schematic diagram of the structure of the lower electrode of a humidity-sensitive capacitor;

[0025] Figure 8 This is the fourth exploded view of a bidirectional three-dimensional heating humidity sensor according to an embodiment of the present invention;

[0026] Figure 9 for Figure 8 A schematic diagram of the cross-sectional structure of a bidirectional three-dimensional heating humidity sensor;

[0027] Figure 10 for Figure 8 A schematic diagram of the structure of the lower electrode of a humidity-sensitive capacitor;

[0028] Figure 11 This is the fifth exploded view of a bidirectional three-dimensional heating humidity sensor according to an embodiment of the present invention;

[0029] Figure 12 for Figure 11 A schematic diagram of the cross-sectional structure of a bidirectional three-dimensional heating humidity sensor.

[0030] The attached diagram lists the components represented by each number as follows:

[0031] 1. Substrate; 2. Lower heating circuit substrate layer; 3. Lower heating circuit; 4. Dielectric layer; 5. Lower electrode metal substrate layer of humidity-sensitive capacitor; 51. Lower electrode metal substrate layer of first local humidity-sensitive capacitor; 52. Lower electrode metal substrate layer of second local humidity-sensitive capacitor; 6. Lower electrode of humidity-sensitive capacitor; 61. Lower electrode of first local humidity-sensitive capacitor; 62. Lower electrode of second local humidity-sensitive capacitor; 7. Humidity-sensing layer; 8. Upper heating circuit; 9. Lower heating circuit metal pad; 10. Lower electrode metal pad of capacitive humidity sensing element; 11. Upper heating circuit metal pad; 12. Output terminal. Detailed Implementation

[0032] Example 1:

[0033] like Figure 1 and Figure 2As shown, an embodiment of the present invention discloses a bidirectional three-dimensional heating humidity sensor, comprising a substrate 1, a lower heating circuit 3, a moisture-sensing layer 7, and an upper heating circuit 8. The substrate 1, lower heating circuit 3, moisture-sensing layer 7, and upper heating circuit 8 are stacked sequentially. It also includes a humidity-sensitive capacitor lower electrode 6 disposed between the moisture-sensing layer 7 and the substrate 1. Furthermore, it includes a lower heating circuit base layer 2 embedded within the substrate 1, with the lower heating circuit 3 disposed on the lower heating circuit base layer 2 and embedded within the substrate 1. The upper heating circuit 8 has two upper heating circuit metal pads 11, and the lower heating circuit 3 has two lower heating circuit metal pads 9.

[0034] The upper heating circuit 8 and the lower heating circuit 3 are both serpentine in shape. The upper heating circuit 8 is integrally formed with the two upper heating circuit metal pads 11, and the lower heating circuit 3 is integrally formed with the two lower heating circuit metal pads 9.

[0035] Heating Principle: By applying a DC voltage to the metal pads of the two heating circuits, a certain current is generated in the circuit. The Joule effect of the current converts electrical energy into heat energy, thereby heating the humidity-sensitive capacitor. The heating circuits also serve as the upper and lower electrodes of the heated humidity-sensitive capacitor; that is, heat is generated inside the structure of the humidity-sensitive capacitor, which is internal heating. Therefore, the heating efficiency is higher than that of indirect heat conduction from external heating circuits. According to the heat formula Q = I... 2 The larger the resistance value R of the heating circuit, namely the upper heating circuit 8 and the lower heating circuit 3, the larger the current value I through the heating circuit. The larger the current, the more heat is generated, that is, the higher the heating efficiency.

[0036] Humidity measurement principle: The humidity-sensitive capacitor structure consists of a lower electrode 6, a humidity-sensitive layer 7, and an upper electrode. It should be noted that the upper heating circuit 8, in addition to its heating function, also serves as the upper electrode of the humidity-sensitive capacitor. The main functional layer is the humidity-sensitive layer 7, which is made of humidity-sensitive materials, such as polyimide film (PI), polystyrene (PS), cellulose acetate (CA), polymethyl methacrylate (PMMA), and other polymer materials. When the humidity of the environment where the humidity-sensitive capacitor is located changes, the humidity-sensitive material absorbs or dehydrates water, and its dielectric constant changes, thereby changing the capacitance value. The electrical signal is transmitted through the metal pads 11 of the upper heating circuit and the metal pads 9 of the lower heating circuit.

[0037] Example 2:

[0038] like Figure 3 and 4As shown, an embodiment of the present invention discloses a bidirectional three-dimensional heating humidity sensor, comprising a substrate 1, a lower heating circuit 3, a humidity-sensing layer 7, and an upper heating circuit 8. The substrate 1, lower heating circuit 3, humidity-sensing layer 7, and upper heating circuit 8 are stacked sequentially. It also includes a humidity-sensitive capacitor lower electrode 6 disposed between the humidity-sensing layer 7 and the substrate 1. A capacitive humidity sensing element lower electrode metal pad 10 is disposed on the humidity-sensitive capacitor lower electrode 6. Furthermore, it includes a dielectric layer 4 disposed between the humidity-sensitive capacitor lower electrode 6 and the substrate 1. It also includes a humidity-sensitive capacitor lower electrode 6 metal substrate layer 5 disposed between the humidity-sensitive capacitor lower electrode 6 and the dielectric layer 4. Finally, it includes a lower heating circuit substrate layer 2 embedded within the substrate 1, with the lower heating circuit 3 disposed on the lower heating circuit substrate layer 2 and embedded within the substrate 1. The dielectric layer 4 covers the lower heating circuit 3. The upper heating circuit 8 has two upper heating circuit metal pads 11, and the lower heating circuit 3 has two lower heating circuit metal pads 9.

[0039] Among them, the upper heating circuit 8 and the lower heating circuit 3 are both serpentine. The upper heating circuit 8 is integrally formed with the two upper heating circuit metal pads 11, the lower heating circuit 3 is integrally formed with the two lower heating circuit metal pads 9, and the lower electrode metal pad 10 of the capacitive humidity sensing element is integrally formed with the lower electrode 6 of the humidity-sensitive capacitor.

[0040] In this process, an output terminal 12 is provided at the layer where the lower electrode 6 of the humidity-sensitive capacitor is located, and the output terminal 12 is separated from the lower electrode 6 of the humidity-sensitive capacitor, that is, the output terminal 12 is not in contact with the lower electrode 6 of the humidity-sensitive capacitor.

[0041] Specifically, current or voltage is applied to the two lower heating circuit metal pads 9 of the lower heating circuit 3 to heat the lower heating circuit 3, and current or voltage is applied to the two upper heating circuit metal pads 11 of the upper heating circuit 8 to heat the upper heating circuit 8.

[0042] The output terminal 12 is electrically connected to one of the upper heating circuit metal pads 11. Current or voltage is applied to the upper heating circuit metal pad 11 and the other upper heating circuit metal pad 11 to heat the upper heating circuit 8. The output terminal 12 can be made of any metal material, such as Au, Cu, Al, Pt, Cr, Ti, TiW, etc. The upper heating circuit metal pad 11 is made of metal with good thermal conductivity, such as metal Pt or metal Cu. The output terminal 12 and the upper heating circuit metal pad 11 adopt a rectangular metal block structure, and the two structures are the same and completely overlap.

[0043] Humidity is measured using the lower electrode metal pad 10 of the capacitive humidity sensing element and any upper heating circuit metal pad 11.

[0044] Example 3:

[0045] like Figure 5 and 6 As shown, an embodiment of the present invention provides a bidirectional three-dimensional heating humidity sensor, comprising a substrate 1, a lower heating circuit 3, a moisture-sensing layer 7, and an upper heating circuit 8. The substrate 1, lower heating circuit 3, moisture-sensing layer 7, and upper heating circuit 8 are sequentially stacked. It also includes a humidity-sensitive capacitor lower electrode 6, disposed between the moisture-sensing layer 7 and the substrate 1. The humidity-sensitive capacitor lower electrode 6 includes a first local humidity-sensitive capacitor lower electrode 61 and a second local humidity-sensitive capacitor lower electrode 62 that are separated from each other. Specifically, the separation between the first local humidity-sensitive capacitor lower electrode 61 and the second local humidity-sensitive capacitor lower electrode 62 is achieved through a gap. Figure 7 As shown, a capacitive humidity sensing element lower electrode metal pad 10 is respectively disposed on the lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode 62 of the second local humidity-sensitive capacitor. The system also includes a metal substrate layer 51 for the lower electrode of the first local humidity-sensitive capacitor and a metal substrate layer 52 for the lower electrode of the second local humidity-sensitive capacitor. The lower electrode 61 is disposed on the metal substrate layer 51, and the lower electrode 62 is disposed on the metal substrate layer 52. A lower heating circuit substrate layer 2 is also included, embedded within the substrate 1. A lower heating circuit 3 is disposed on the lower heating circuit substrate layer 2 and embedded within the substrate 1. A dielectric layer 4 is also included, disposed between the lower electrode 6 of the humidity-sensitive capacitor and the substrate 1. The metal substrate layer 51 for the lower electrode of the first local humidity-sensitive capacitor is located between the dielectric layer 4 and the lower electrode 61, and the metal substrate layer 52 for the lower electrode of the second local humidity-sensitive capacitor is located between the dielectric layer 4 and the lower electrode 62. The dielectric layer 4 covers the lower heating circuit 3.

[0046] The upper heating circuit 8 and the lower heating circuit 3 are both serpentine in shape. The upper heating circuit 8 is integrally formed with the two upper heating circuit metal pads 11, and the lower heating circuit 3 is integrally formed with the two lower heating circuit metal pads 9. The lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode metal pad 10 of the capacitive humidity sensing element are integrally formed, and the lower electrode 62 of the second local humidity-sensitive capacitor and the lower electrode metal pad 10 of the capacitive humidity sensing element are integrally formed.

[0047] In this process, voltage is applied to the two lower heating circuit metal pads 9 of the lower heating circuit 3 to heat the lower heating circuit 3, and voltage is applied to the two upper heating circuit metal pads 11 of the upper heating circuit 8 to heat the upper heating circuit 8. Humidity is measured through the lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode 62 of the second local humidity-sensitive capacitor.

[0048] Example 4:

[0049] like Figure 8 and 9As shown, an embodiment of the present invention provides a bidirectional three-dimensional heating humidity sensor, comprising a substrate 1, a lower heating circuit 3, a moisture-sensing layer 7, and an upper heating circuit 8. The substrate 1, lower heating circuit 3, moisture-sensing layer 7, and upper heating circuit 8 are stacked sequentially. It also includes a humidity-sensitive capacitor lower electrode 6, disposed between the moisture-sensing layer 7 and the substrate 1. The humidity-sensitive capacitor lower electrode 6 includes a first local humidity-sensitive capacitor lower electrode 61 and a second local humidity-sensitive capacitor lower electrode 62 that are separated from each other. Specifically, the separation between the first local humidity-sensitive capacitor lower electrode 61 and the second local humidity-sensitive capacitor lower electrode 62 is achieved through an interdigitated arrangement. Figure 10 As shown, a capacitive humidity sensing element lower electrode metal pad 10 is respectively disposed on the lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode 62 of the second local humidity-sensitive capacitor. The system also includes a metal substrate layer 51 for the lower electrode of the first local humidity-sensitive capacitor and a metal substrate layer 52 for the lower electrode of the second local humidity-sensitive capacitor. The lower electrode 61 is disposed on the metal substrate layer 51, and the lower electrode 62 is disposed on the metal substrate layer 52. A lower heating circuit substrate layer 2 is also included, embedded within the substrate 1. A lower heating circuit 3 is disposed on the lower heating circuit substrate layer 2 and embedded within the substrate 1. A dielectric layer 4 is also included, disposed between the lower electrode 6 of the humidity-sensitive capacitor and the substrate 1. The metal substrate layer 51 for the lower electrode of the first local humidity-sensitive capacitor is located between the dielectric layer 4 and the lower electrode 61, and the metal substrate layer 52 for the lower electrode of the second local humidity-sensitive capacitor is located between the dielectric layer 4 and the lower electrode 62. The dielectric layer 4 covers the lower heating circuit 3.

[0050] The upper heating circuit 8 and the lower heating circuit 3 are both serpentine in shape. The upper heating circuit 8 is integrally formed with the two upper heating circuit metal pads 11, and the lower heating circuit 3 is integrally formed with the two lower heating circuit metal pads 9. The lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode metal pad 10 of the capacitive humidity sensing element are integrally formed, and the lower electrode 62 of the second local humidity-sensitive capacitor and the lower electrode metal pad 10 of the capacitive humidity sensing element are integrally formed.

[0051] In this process, voltage is applied to the two lower heating circuit metal pads 9 of the lower heating circuit 3 to heat the lower heating circuit 3, and voltage is applied to the two upper heating circuit metal pads 11 of the upper heating circuit 8 to heat the upper heating circuit 8. Humidity is measured through the lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode 62 of the second local humidity-sensitive capacitor.

[0052] Example 5:

[0053] like Figure 11 and Figure 12As shown, an embodiment of the present invention provides a bidirectional three-dimensional heating humidity sensor, comprising a substrate 1, a lower heating circuit 3, a humidity-sensing layer 7, and an upper heating circuit 8. The lower heating circuit 3, substrate 1, humidity-sensing layer 7, and upper heating circuit 8 are stacked sequentially. It also includes a humidity-sensitive capacitor lower electrode 6, disposed between the humidity-sensing layer 7 and the substrate 1. The humidity-sensitive capacitor lower electrode 6 includes a first local humidity-sensitive capacitor lower electrode 61 and a second local humidity-sensitive capacitor lower electrode 62, which are separated from each other. Specifically, the separation between the first local humidity-sensitive capacitor lower electrode 61 and the second local humidity-sensitive capacitor lower electrode 62 is achieved through a gap. A capacitive humidity sensing element lower electrode metal pad 10 is respectively disposed on the first local humidity-sensitive capacitor lower electrode 61 and the second local humidity-sensitive capacitor lower electrode 62. The sensor also includes a first local humidity-sensitive capacitor lower electrode metal substrate layer 51 and a second local humidity-sensitive capacitor lower electrode metal substrate layer 52. The first local humidity-sensitive capacitor lower electrode 61 is disposed on the first local humidity-sensitive capacitor lower electrode metal substrate layer 51, and the second local humidity-sensitive capacitor lower electrode 62 is disposed on the second local humidity-sensitive capacitor lower electrode metal substrate layer 52. It also includes a lower heating circuit substrate layer 2 embedded in the substrate 1 or deposited on the surface of the substrate 1, and a lower heating circuit 3 disposed on the lower heating circuit substrate layer 2, and the lower heating circuit 3 is embedded in the substrate 1 or deposited on the surface of the substrate 1.

[0054] The upper heating circuit 8 and the lower heating circuit 3 are both serpentine in shape. The upper heating circuit 8 is integrally formed with the two upper heating circuit metal pads 11, and the lower heating circuit 3 is integrally formed with the two lower heating circuit metal pads 9. The lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode metal pad 10 of the capacitive humidity sensing element are integrally formed, and the lower electrode 62 of the second local humidity-sensitive capacitor and the lower electrode metal pad 10 of the capacitive humidity sensing element are integrally formed.

[0055] In this process, voltage is applied to the two lower heating circuit metal pads 9 of the lower heating circuit 3 to heat the lower heating circuit 3, and voltage is applied to the two upper heating circuit metal pads 11 of the upper heating circuit 8 to heat the upper heating circuit 8. Humidity is measured through the lower electrode 61 of the first local humidity-sensitive capacitor and the lower electrode 62 of the second local humidity-sensitive capacitor.

[0056] The substrate 1 can be made of silicon-based materials such as glass, quartz, ceramic, piezoelectric substrate, polycrystalline silicon, and amorphous silicon; the lower heating circuit substrate 2, the lower electrode metal substrate 5 of the humidity-sensitive capacitor, the lower electrode metal substrate 51 of the first local humidity-sensitive capacitor, the lower electrode metal substrate 52 of the second local humidity-sensitive capacitor, and the output terminal 12 can be made of various metals or alloys such as Ti, Cr, TiW, Ni, NiCr, and Ta.

[0057] The lower electrode 6 of the humidity-sensitive capacitor, the lower electrode 61 of the first local humidity-sensitive capacitor, the lower electrode 62 of the second local humidity-sensitive capacitor, and the metal pad 10 of the lower electrode of the capacitive humidity sensing element can all be made of any metal material, such as Au, Cu, Al, Pt and other metal materials with good conductivity.

[0058] The lower heating circuit 3, upper heating circuit 8, lower heating circuit metal pad 9, and upper heating circuit metal pad 11 can all be made of metals with good thermal conductivity, such as platinum (Pt) or copper (Cu); the dielectric layer 4 can be made of SiO2 or SiN. x or polymers and other compounds;

[0059] The moisture-sensing layer 7 can be made of polymer materials such as polyimide film (PI), polystyrene (PS), cellulose acetate (CA), and polymethyl methacrylate (PMMA).

[0060] The bidirectional vertical three-dimensional heating humidity sensor structure of this invention mainly includes: two heating circuits, namely an upper heating circuit 8 and a lower heating circuit 3, and a humidity-sensitive capacitor's main functional layer, namely a humidity-sensing layer 7. The two heating circuits are respectively distributed in the upper and lower directions of the humidity-sensitive capacitor structure. Depending on the structure of the humidity-sensitive capacitor used, the functional area distribution of the heating circuits varies, and the functions of the various leads of the two heating circuits and the humidity-sensitive capacitor differ accordingly. This allows for the design of a matching circuit board structure for application in humidity sensor devices. The bidirectional three-dimensional heating humidity sensor proposed in this invention offers flexible structural design, diverse options, and suitability for humidity measurement devices with different application requirements.

[0061] The heating circuit can be either meandering or spiral-shaped, with two electrode leads. The heating circuit structures in the upper and lower directions can be identical or different; that is, the upper heating circuit 8 and the lower heating circuit 3 can have the same or different structures, depending on the specific application requirements. If a lower heating temperature gradient is required, a heating circuit with a larger resistance value can be selected for the upper heating circuit 8 and the lower heating circuit 3. If a higher heating temperature gradient and higher heating uniformity are required, a meandering circuit structure with a smaller resistance value can be selected for the upper heating circuit 8 and the lower heating circuit 3.

[0062] There are three main types of humidity-sensitive capacitor structures: sandwich type, dual-bottom-electrode type, and interdigitated type. Any of these structures can be applied to the bidirectional three-dimensional heating humidity sensor structure of this invention. The lower heating circuit metal layer can be shared with the lower electrode 6 metal layer of the humidity-sensitive capacitor, or the heating circuit metal layer and the lower electrode 6 metal layer of the humidity-sensitive capacitor can be fabricated separately. To ensure the sensitivity of humidity measurement and minimize the contact path between water vapor and the humidity-sensitive layer 7, the upper heating circuit adopts a structure that shares the upper electrode metal layer of the humidity-sensitive capacitor.

[0063] Structure 1: The metal layer of the lower electrode 6 of the humidity-sensitive capacitor and the metal layer of the heating circuit are not shared; they are fabricated separately. The heating circuit can be designed below the lower electrode 6 of the humidity-sensitive capacitor. The two metal layers are separated by the fabrication of SiO2 and SiN. x Alternatively, a polymer or other compound can be used as the dielectric layer 4 to insulate the two metal layers; or the heating circuit can be fabricated on the back side of the substrate, with the heating circuit functional area located directly below the humidity-sensitive capacitor functional area structure, and the substrate directly serving as the insulating dielectric layer 4. The fabrication methods are as follows:

[0064] Method 1: Prepare thin-film heating resistors on the substrate surface using sputtering, thermal evaporation, electroplating, or electron beam evaporation, and then prepare SiO2 and SiN on top of the thin-film heating resistors. x Or polymers and other compounds; then, on top of the dielectric layer 4, the metal layer of the lower electrode 6 of the humidity-sensitive capacitor, the humidity-sensitive layer 7, and the upper electrode / heating circuit of the humidity-sensitive capacitor are sequentially prepared to complete the preparation of the bidirectional three-dimensional heating humidity sensor.

[0065] Method 2: First, an etching process is used to etch a heating circuit groove structure on the substrate surface. Then, a thin-film heating resistor is fabricated on the substrate surface using sputtering, thermal evaporation, electroplating, or electron beam evaporation, with the thickness consistent with the etching depth. At this point, the substrate surface is planar, and the heating circuit is an embedded structure. Finally, SiO2 and SiN are fabricated on top of the thin-film heating resistor. x Alternatively, a polymer or other compound dielectric layer 4 is formed; then, a metal layer of the lower electrode 6 of the humidity-sensitive capacitor, a humidity-sensitive layer 7, and a heating circuit above the upper electrode of the humidity-sensitive capacitor are sequentially formed on the dielectric layer 4 to complete the fabrication of a bidirectional three-dimensional heating humidity sensor.

[0066] Method 3: Select a double-polished substrate and fabricate a heating resistor on the back of the substrate. The heating circuit functional area is located directly below the structure of the humidity-sensitive capacitor functional area. The heating circuit can be fabricated using either Method 1 or Method 2, respectively, as a surface heating circuit or an embedded heating circuit. Then, on the front of the substrate, fabricate the lower electrode 6 metal layer, the humidity-sensitive layer 7, and the upper electrode metal layer of the humidity-sensitive capacitor, as well as the heating circuit above the upper electrode of the humidity-sensitive capacitor, to complete the fabrication of the bidirectional three-dimensional heating humidity sensor.

[0067] Structure 2: The metal layer of the lower electrode 6 of the humidity-sensitive capacitor is shared with the metal layer of the heating circuit. That is, the metal layer of the lower electrode 6 of the humidity-sensitive capacitor and the metal layer of the heating circuit are the same metal layer. They can be prepared into surface-type or embedded metal layer structures by either method 1 or method 2 above. Then, the humidity-sensitive layer 7 and the upper electrode metal layer / the heating circuit above the humidity-sensitive capacitor are prepared on the surface of the metal layer of the lower electrode 6 of the humidity-sensitive capacitor / the metal layer of the heating circuit, thus completing the preparation of the bidirectional three-dimensional heating humidity sensor.

[0068] If the metal layer of the lower electrode 6 of the humidity-sensitive capacitor and the metal layer of the heating circuit are used in a shared structure, the structure of the bidirectional three-dimensional heating humidity sensor is simpler and the processing technology is more simplified. Moreover, since the upper heating circuit and the lower heating circuit both act directly on the upper and lower surfaces of the humidity-sensitive layer 7, the heating effect at low temperatures is better and the temperature error is further reduced.

[0069] Furthermore, if an embedded heating circuit / or the lower electrode 6 of the humidity-sensitive capacitor is simultaneously fabricated through an etching process, the thickness and volume of the bidirectional three-dimensional heating humidity sensor will be reduced, thereby lowering the cost and making it easier to reduce the load mass of the radiosonde for upper-air meteorological humidity detection.

[0070] When the bidirectional three-dimensional heating humidity sensor of this invention is placed in an exposed air environment for humidity measurement, the heating effect on the humidity-sensitive capacitor at low temperatures is better. The heating directly acts on both the upper and lower directions of the humidity-sensitive capacitor, increasing the heating rate and temperature, and more quickly removing surface frost or atmospheric pollutants. Heating the humidity-sensitive capacitor reduces humidity measurement error and improves measurement accuracy. The bidirectional three-dimensional heating humidity sensor offers multiple structural options and flexible applications. Furthermore, by optimizing the structure of the humidity-sensitive device, the sensor's size can be reduced, lowering costs, and it shows promise for application in high-altitude meteorological detection.

[0071] An embodiment of the present invention provides a device with humidity acquisition function, comprising a bidirectional three-dimensional heating humidity sensor as described above. The device with humidity acquisition function includes upper-air meteorological radiosonde equipment, ground meteorological humidity detector equipment, indoor environmental humidity monitoring equipment, integrated temperature and humidity sensor equipment, etc.

[0072] In this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0073] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0074] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A bidirectional three-dimensional heating humidity sensor, characterized in that, It includes a substrate, a lower heating circuit, a moisture-sensing layer, and an upper heating circuit, wherein the substrate, the lower heating circuit, the moisture-sensing layer, and the upper heating circuit are stacked sequentially, or the lower heating circuit, the substrate, the moisture-sensing layer, and the upper heating circuit are stacked sequentially. It also includes a lower electrode of a humidity-sensitive capacitor, which is disposed between the moisture-sensitive layer and the substrate; It also includes a dielectric layer disposed between the lower electrode of the humidity-sensitive capacitor and the substrate; The dielectric layer is applied over the lower heating circuit; The metal layer to which the lower electrode of the humidity-sensitive capacitor belongs and the metal layer to which the lower heating circuit belongs are the same metal layer, and the metal layers are prepared separately. The lower heating circuit is located below the lower electrode of the humidity-sensitive capacitor, and the dielectric layer is prepared between the two metal layers. Alternatively, the lower heating circuit is prepared on the back side of the substrate, and the substrate is used as the insulating dielectric layer. Alternatively, the metal layer to which the lower electrode of the humidity-sensitive capacitor belongs is the same metal layer as the metal layer to which the lower heating circuit belongs.

2. The bidirectional three-dimensional heating humidity sensor according to claim 1, characterized in that, The humidity-sensitive capacitor lower electrode includes a first local humidity-sensitive capacitor lower electrode and a second local humidity-sensitive capacitor lower electrode that are separated from each other. A capacitive humidity sensing element lower electrode metal pad is respectively provided on the first local humidity-sensitive capacitor lower electrode and the second local humidity-sensitive capacitor lower electrode.

3. A bidirectional three-dimensional heating humidity sensor according to claim 2, characterized in that, It also includes a first local humidity-sensitive capacitor lower electrode metal substrate layer and a second local humidity-sensitive capacitor lower electrode metal substrate layer, wherein the first local humidity-sensitive capacitor lower electrode is disposed on the first local humidity-sensitive capacitor lower electrode metal substrate layer, and the second local humidity-sensitive capacitor lower electrode is disposed on the second local humidity-sensitive capacitor lower electrode metal substrate layer.

4. A bidirectional three-dimensional heating humidity sensor according to any one of claims 1 to 3, characterized in that, It also includes a lower heating circuit substrate layer embedded in the substrate, wherein the lower heating circuit is disposed on the lower heating circuit substrate layer and the lower heating circuit is embedded in the substrate.

5. A bidirectional three-dimensional heating humidity sensor according to any one of claims 1 to 3, characterized in that, The upper heating circuit is provided with two upper heating circuit metal pads.

6. A bidirectional three-dimensional heating humidity sensor according to any one of claims 1 to 3, characterized in that, The lower heating circuit is provided with two lower heating circuit metal pads.

7. A device with humidity acquisition function, characterized in that, Includes a bidirectional three-dimensional heating humidity sensor as described in any one of claims 1 to 6.

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