Dual-channel resonant temperature and humidity sensor chip, sensing system, and processing method

Abstract

The present invention relates to a dual-channel resonant temperature and humidity sensor chip, a sensing system, and a processing method. The dual-channel resonant temperature and humidity sensor chip comprises: a quartz wafer substrate, on which a working crystal oscillator unit, a reference crystal oscillator unit, and a temperature measurement unit are formed. The working crystal oscillator unit comprises an electrode, a moisture-sensitive film disposed on the working electrode, and an electrode epitaxial region; the reference crystal oscillator unit comprises a reference electrode and an electrode epitaxial region; the temperature measurement unit comprises a temperature measurement element, a lead epitaxial region, and an insulating layer, wherein the lead epitaxial region connects two ends of the temperature measurement element; the insulating layer covers the temperature measurement element and the lead epitaxial region; the working crystal oscillator unit and the reference crystal oscillator unit respectively vibrate under excitation of a driving circuit to output an amplitude signal and a frequency signal, and the temperature measurement unit outputs a resistance signal. The present invention can implement a temperature-frequency compensation function, eliminating the influence of temperature on the temperature and humidity while measuring them, thereby improving measurement accuracy.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a dual-channel resonant temperature and humidity sensor chip, a sensing system, and a processing method. Background Art

[0002] Temperature and humidity are two important physical quantities, closely intertwined with our daily lives, from daily life to industrial and agricultural development, meteorological observation, biomedicine, aerospace exploration, and other aspects. Furthermore, the two physical quantities are closely linked and often used for comprehensive monitoring. Therefore, the ability to accurately and conveniently measure temperature and humidity is particularly important. Currently, there are many different temperature and humidity sensor measurement methods on the market. Temperature measurement methods include thermocouple, resistive, and fiber optic types, while humidity measurement methods include capacitive resistance, piezoelectric resonance, and chilled mirror types. Among them, piezoelectric resonant humidity sensors are widely used due to their high precision, wide measurement range, fast response, and stable frequency output.

[0003] However, in the field of resonant humidity measurement, temperature can cause drift in the resonant output frequency, reducing accuracy. In severe cases, it may overwhelm the required humidity signal, resulting in a large number of measurement errors, making it difficult for the entire measurement system to operate normally. Therefore, it is necessary to perform temperature compensation on the humidity response when measuring humidity using a resonant humidity sensor. Traditional temperature compensation solutions are mainly divided into hardware compensation and software compensation. However, the circuits built with electronic components in hardware compensation cannot meet the requirements of places that require real-time performance and high compensation accuracy. The software compensation algorithm generally has a large number of iterations, a complex algorithm, and a slow convergence speed. In summary, there is still a need for a good temperature-frequency compensation method to solve the temperature drift problem in the field of resonant humidity measurement. Summary of the Invention

[0004] The present invention provides a dual-channel resonant temperature and humidity sensor chip, a sensor chip, and a processing method to solve the temperature drift problem in the existing resonant humidity measurement field.

[0005] To achieve the above objectives, the present invention provides a dual-channel resonant temperature and humidity sensor chip, comprising:

[0006] A quartz wafer substrate, on which a working crystal oscillator unit, a reference crystal oscillator unit, and a temperature measurement unit are formed, wherein:

[0007] The working crystal oscillator unit includes a working electrode, a moisture-sensitive film arranged on the working electrode, and an electrode epitaxial region connected to the working electrode;

[0008] The reference crystal oscillator unit includes a reference electrode and an electrode epitaxial region connected to the reference electrode;

[0009] The temperature measuring unit includes a temperature measuring element, a lead epitaxial region and an insulating layer, wherein the lead epitaxial region connects two ends of the temperature measuring element; the insulating layer covers the temperature measuring element and the lead epitaxial region;

[0010] The working crystal oscillator unit and the reference crystal oscillator unit respectively generate vibrations under the excitation of the driving circuit to output amplitude signals and frequency signals, and the temperature measuring unit outputs resistance signals.

[0011] Furthermore, the working crystal oscillator unit includes working electrodes arranged on the upper and lower surfaces of the quartz wafer substrate, a moisture-sensitive film arranged on the working electrodes, and electrode epitaxial regions arranged on the upper and lower surfaces of the quartz wafer substrate and connected to the working electrodes;

[0012] The reference crystal oscillator unit includes reference electrodes arranged on the upper and lower surfaces of the quartz wafer substrate and electrode epitaxial regions arranged on the upper and lower surfaces of the quartz wafer substrate and connected to the reference electrodes; further, the material of the crystal oscillator unit electrode is a gold electrode or a silver electrode.

[0013] Furthermore, the material of the moisture-sensitive film includes any one of graphene oxide, graphyne, carbon nanotubes, chitosan and cellulose.

[0014] Furthermore, the temperature measuring element in the temperature measuring unit is a platinum resistor.

[0015] Furthermore, the quartz wafer substrate is in the shape of a disc, and the surfaces of the working electrode and the reference electrode are both circular; the platinum resistor is located at a position where the perpendicular line between the centers of the working electrode and the reference electrode is close to the center of the substrate, and its length direction is parallel to the line connecting the centers of the working electrode and the reference electrode.

[0016] Furthermore, the material of the insulating layer is silicon nitride.

[0017] Furthermore, the working electrode and the reference electrode are symmetrically distributed at the center of the semicircles on both sides of the quartz wafer substrate with respect to the center of the quartz wafer substrate.

[0018] Furthermore, the lead extension regions on both sides of the temperature measuring element do not block the central axis of the quartz wafer substrate.

[0019] The present invention also relates to a dual-channel resonant temperature and humidity sensing system: comprising the above-mentioned dual-channel resonant temperature and humidity sensor chip, and also comprising a dual-channel driving circuit, a temperature measurement circuit and a temperature-frequency compensation humidity measurement circuit, wherein the first channel of the dual-channel driving circuit is connected to the epitaxial region of the working electrode, and the second channel of the dual-channel driving circuit is connected to the epitaxial region of the reference electrode, so that the quartz wafer generates resonance through its own piezoelectric effect; the temperature measurement circuit is connected to the epitaxial region of the lead electrode of the temperature measuring unit in the temperature and humidity sensor chip to measure the resistance; the temperature-frequency compensation humidity measurement circuit is respectively connected to the electrode epitaxial region of the working electrode and the electrode epitaxial region of the reference electrode.

[0020] The present invention also relates to a method for processing a dual-channel resonant temperature and humidity sensor chip, which is used to process the dual-channel resonant temperature and humidity sensor chip, comprising the following steps:

[0021] Quartz crystal processing: The chip substrate is processed by mechanical processing. The quartz crystal rod is oriented by X-ray and then cut into quartz wafers. The cut quartz wafers are ground and processed in size and shape to complete the processing of the chip substrate.

[0022] Processing and manufacturing of the crystal oscillator unit: The working crystal oscillator unit and the reference crystal oscillator unit are processed on the upper and lower surfaces of a thickness-sheared quartz wafer using an evaporation process. The working electrode and the reference electrode are composed of circular gold or silver-plated electrodes. Each side of the working electrode and the reference electrode is plated with an electrode epitaxial region for lead wires. The prepared humidity-sensing material is deposited on the working electrode to form a humidity-sensing film.

[0023] Processing and manufacturing of the temperature measurement unit: A platinum resistor is deposited on the non-electrode area of ​​the quartz wafer through the MEMS process. A lead plate is deposited at both ends of the platinum resistor as a lead epitaxial area, and a layer of insulating material is coated on the surface of the platinum resistor.

[0024] The present invention proposes a dual-channel resonant temperature and humidity sensor chip and processing method, which can be used as a temperature and humidity sensor chip with temperature-frequency compensation in resonant temperature and humidity measurement methods and sensitive circuit temperature and humidity measurement methods. The chip provided by the present invention can not only measure and sense ambient temperature and humidity using the resonant or electrical characteristics of a quartz wafer, but also achieve temperature compensation during measurement and identification, eliminating the impact of temperature on the resonant or electrical characteristics of the quartz wafer. The sensing principle and implementation method proposed by the present invention respectively place the working crystal oscillator unit, the reference crystal oscillator unit, and the temperature measurement unit in three different working circuits, avoiding the influence of each unit on the operation of other units and ensuring the reliability of each unit's independent operation. The preparation process proposed by the present invention does not overlap the working crystal oscillator unit and the reference crystal oscillator unit during preparation, ensuring the normal operation of the two crystal oscillator units. The platinum resistor is deposited on the non-electrode area of ​​the quartz wafer through a MEMS process, avoiding the problems of affecting vibration characteristics and temperature gradient distribution caused by the rigid contact between the platinum resistor and the quartz wafer, and can achieve high-precision measurement of temperature and humidity. This invention can provide a high-precision, integrated, and easily replaceable core temperature-frequency compensation temperature and humidity chip for the industrialization of resonant temperature and humidity measuring instruments, and its preparation process and usage method are inexpensive and simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of a dual-channel resonant temperature and humidity sensor chip in Example 1 of the present invention.

[0026] Figure 2 This is a structural diagram of a dual-channel resonant temperature and humidity sensing system in Example 2 of the present invention.

[0027] Figure 3 This is a flow chart of a method for processing a dual-channel resonant temperature and humidity sensor chip in embodiment three of the present invention.

[0028] In the figure: quartz wafer substrate 100, working electrode 201, electrode epitaxial region 202, humidity sensitive film 203, reference electrode 301, electrode epitaxial region 302, temperature measuring element 401, lead epitaxial region 402, insulating layer 403, dual-channel driving circuit 501, temperature-frequency compensated humidity measurement circuit 502, temperature measurement circuit 503. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0030] Example 1

[0031] A dual-channel resonant temperature and humidity sensor chip, please refer to Figure 1 , comprising: a quartz wafer substrate 100, two crystal oscillator units and a temperature measurement unit formed on the substrate, the two crystal oscillator units including a working crystal oscillator unit and a reference crystal oscillator unit, wherein:

[0032] The working crystal oscillator unit includes a working electrode 201 arranged on the upper and lower surfaces of the quartz wafer substrate 100, a moisture-sensitive film 203 arranged on the working electrode 201, and an electrode epitaxial region 202 arranged on the upper and lower surfaces of the quartz wafer substrate 100 and connected to the working electrode 201; the reference crystal oscillator unit includes a reference electrode 301 arranged on the upper and lower surfaces of the quartz wafer substrate 100 and an electrode epitaxial region 202 arranged on the upper and lower surfaces of the quartz wafer substrate 100 and connected to the reference electrode 301; the temperature measuring unit includes a temperature measuring element 401, a lead epitaxial region 402 and an insulating layer 403, wherein the lead epitaxial region 402 connects the two ends of the temperature measuring element 401; the insulating layer 403 covers the temperature measuring element 401 and the lead epitaxial region 402; the working crystal oscillator unit and the reference crystal oscillator unit respectively generate vibrations under the excitation of the driving circuit to output amplitude signals and frequency signals, and the temperature measuring unit outputs a resistance signal.

[0033] The crystal oscillator unit electrodes are made of gold or silver. The humidity-sensing film 203 is made of any of graphene oxide, graphyne, carbon nanotubes, chitosan, and cellulose. The temperature measuring element 401 in the temperature measuring unit is a platinum resistor. The quartz wafer substrate 100 is disc-shaped, and both the working electrode 201 and the reference electrode 301 have circular surfaces. The insulating layer 403 is made of silicon nitride.

[0034] For some optional size designs in this embodiment, the detailed position distribution is as follows Figure 1 As shown in FIG. The diameter of the working electrode 201 and the reference electrode 301 is approximately 1 / 4 of the diameter of the quartz crystal. The working electrode 201 and the reference electrode 301 are symmetrically distributed in the center of the semicircle on both sides of the quartz wafer substrate 100 relative to the center of the circle. The platinum resistance is located at a position close to the center of the substrate, perpendicular to the center of the working electrode 201 and the reference electrode 301, and its length is parallel to the line connecting the centers of the working electrode 201 and the reference electrode 301.

[0035] The epitaxial region on one side of the working electrode 201 and the reference electrode 301 epitaxial region 202 on the same side thereof are each along the substrate diameter direction, extending outwards to the substrate edge for connection with an external drive circuit. The epitaxial region on the back side of the working electrode 201 and the reference electrode 301 epitaxial region 202 are respectively at a certain angle (about 60 °) to the epitaxial region direction of the front side, extending outwards to the substrate edge for connection with an external drive circuit. The lead epitaxial region 402 on both sides of the platinum resistor is at a certain angle (about 60 °) to the length direction of the platinum resistor, extending to the substrate edge on the same side and in the opposite direction to the back electrode epitaxial region 202, for connection with an external measurement circuit. The epitaxial region on one side of the working electrode 201 and the reference electrode 301 epitaxial region 202 on the same side thereof are each along the substrate diameter direction, extending outwards to the substrate edge for connection with an external drive circuit. The epitaxial regions of the working electrode 201 and the reference electrode 301 on the back extend at an angle (approximately 60°) to the epitaxial region on the front side, extending outward to the substrate edge for connection to external drive circuitry. The epitaxial regions 402 of the lead wires on either side of the platinum resistor extend at an angle (approximately 60°) to the length of the resistor, extending to the substrate edge on the same side, opposite to the epitaxial region 202 on the back side, for connection to external measurement circuitry.

[0036] The humidity-sensing film 203 is concentric with the working electrode 201 and has a diameter slightly smaller than that of the working electrode 201. An insulating layer 403 covers the entire temperature measurement unit. The thicknesses of the quartz wafer, working electrode 201, and reference electrode 301 are determined based on the humidity frequency measurement requirements, while the length and width of the platinum resistance resistor are determined based on the temperature measurement requirements. The lead extensions 402 on either side of the temperature measurement element 401 do not obstruct the central axis of the quartz wafer substrate 100. The central axis is the direction of the sensor's air flow to avoid interfering with the operation of the quartz wafer substrate 100.

[0037] Example 2

[0038] like Figure 2 As shown, a dual-channel resonant temperature and humidity sensing system includes: a dual-channel drive circuit 501, a temperature-frequency compensated humidity measurement circuit 502, a temperature measurement circuit 503, and a dual-channel resonant temperature and humidity sensor chip according to one of the above embodiments. The dual-channel drive circuit 501 module and the temperature-frequency compensated humidity measurement module are respectively and simultaneously connected to the epitaxial region of the working electrode 201 and the epitaxial region of the reference electrode 301 in the temperature and humidity sensor chip, optionally by welding. The temperature measurement module is connected to the lead electrode epitaxial region 202 of the temperature measurement unit in the temperature and humidity sensor chip, optionally by welding.

[0039] Among them, the first channel of the dual-channel driving circuit 501 is connected to the epitaxial region of the working electrode 201, and the second channel of the dual-channel driving circuit 501 is connected to the epitaxial region of the reference electrode 301, so that the quartz wafer generates resonance through its own piezoelectric effect; the temperature measurement circuit 503 is connected to the epitaxial region 202 of the lead electrode of the temperature measurement unit in the temperature and humidity sensor chip to measure resistance; the temperature-frequency compensation humidity measurement circuit 502 is respectively connected to the electrode epitaxial region 202 of the working electrode 201 and the electrode epitaxial region 202 of the reference electrode 301.

[0040] The sensing principle of a dual-channel resonant temperature and humidity sensor system is as follows: the chip is exposed to the actual measured environment. Under the stimulation of a driving circuit, two crystal oscillators vibrate, and the vibration frequency changes with the measured environment. The temperature measurement unit is connected to an external temperature measurement circuit, and the resistance of a platinum resistor changes with the measured ambient temperature. The difference in frequency (frequency difference) between the working crystal oscillator and the reference crystal oscillator is used to measure the ambient humidity, while the resistance of the platinum resistor is used to measure the ambient temperature.

[0041] When a crystal oscillator unit is affected by external mass changes (such as the increase in mass caused by absorbing water vapor in the environment) and temperature changes, its own vibration frequency will change accordingly based on the external mass and temperature. The specific relationship with the external mass change is shown in Equation 1:

[0042]

[0043] Where: Δf 质 - Frequency changes of the crystal oscillator unit caused by changes in external mass;

[0044] Δm – external mass change;

[0045] f0——initial natural frequency of the crystal oscillator unit;

[0046] M——Quartz wafer quality.

[0047] The specific relationship with temperature change is shown in Equation 2:

[0048] Δf 温 =f0·[a0(T-T0)+b0(T-T0) 2 +c0(T-T0) 3 ] (2)

[0049] Where: Δf 温 - Frequency changes of the crystal oscillator unit caused by changes in external mass;

[0050] f0——initial natural frequency of the crystal oscillator unit;

[0051] T——ambient temperature;

[0052] T0 - reference temperature at natural frequency;

[0053] a0, b0, c0 - first-order, second-order and third-order temperature coefficients at reference temperature T0.

[0054] The temperature-frequency compensation function is implemented in the following way: the humidity-sensitive film 203 in the working crystal oscillator unit absorbs water vapor in the actual environment to be measured, causing the mass change on the electrode, thereby causing the vibration frequency of the working crystal oscillator unit to change. At the same time, the vibration frequency of the working crystal oscillator unit will also change with temperature. The specific change Δf of the working crystal oscillator unit is 工 As shown in formula 3:

[0055] Δf 工 =Δf 质 +Δf 温 (3)

[0056] The reference crystal oscillator unit will not absorb water vapor in the actual test environment, and its vibration frequency only changes with temperature. The specific change of the reference crystal oscillator unit Δf 参 As shown in formula 4:

[0057] Δf 参 =Δf 温 (4)

[0058] By collecting the vibration frequency signals of the working crystal oscillator unit and the reference crystal oscillator unit and performing difference processing, the difference frequency Δf between the two units is obtained. 差频 for:

[0059] Δf 差频 =Δf 工 -Δf 参 =Δf 质 +Δf 温 -Δf 温 =Δf 质 (5)

[0060] This difference frequency is the frequency change Δf of the crystal oscillator unit caused by the external mass change alone. 质 The difference frequency processing offsets the interference of temperature on the vibration frequency of the working crystal oscillator unit, thus realizing the function of temperature-frequency compensation. Finally, the external mass change Δm, i.e., the mass of water vapor adsorbed by the humidity-sensing film 203, is calculated by equation (1). The ambient humidity is calculated using the water vapor mass, thus realizing humidity measurement.

[0061] The relationship between the resistance value of platinum resistors is shown in formula 6:

[0062]

[0063] Where: R - resistance of platinum resistor; L - length of platinum resistor; S - cross-sectional area of ​​platinum resistor;

[0064] ρ——Resistivity of platinum resistance.

[0065] The resistivity ρ will change with the change of temperature, thus causing the change of the resistance value of the platinum resistor. This phenomenon is used to achieve temperature measurement and sensing.

[0066] As a preferred embodiment, the working crystal oscillator unit and the reference crystal oscillator unit adopt dual-channel excitation, and the same driving circuit alternately excites the two crystal oscillator units at high frequency to avoid mechanical-electromagnetic interference between the two crystal oscillator units.

[0067] Example 3

[0068] like Figure 3 As shown, the present invention also relates to a dual-channel resonant temperature and humidity sensor chip processing method, which is used to process a dual-channel resonant temperature and humidity sensor chip of embodiment 1, comprising the following steps:

[0069] Processing and production of S1 quartz crystal: The processing technology of the chip substrate adopts mechanical processing, uses X-rays for angle measurement and orientation, cuts the quartz crystal rod that has completed angle measurement and orientation into quartz wafers, and then grinds the cut quartz wafers. The size and shape of the wafers are processed according to the design requirements, and finally the quartz wafers are cleaned to complete the processing of the chip substrate.

[0070] Processing and Fabrication of the S2 Crystal Oscillator Unit: Crystal oscillator units (including a working crystal oscillator unit and a reference crystal oscillator unit) are fabricated on both the upper and lower surfaces of a thickness-sheared quartz wafer using an evaporation process. The working electrode 201 and the reference electrode 301 are each formed from circular gold or silver electrodes. Each side of the working electrode 201 and the reference electrode 301 is plated with an electrode epitaxial region 202 for wiring. The external drive circuit, in contact with the electrode epitaxial region 202, causes the quartz wafer to resonate through its own piezoelectric effect. A separate moisture-sensitive film 203 is prepared for the working crystal oscillator unit. The prepared moisture-sensitive material is deposited on the electrodes of the working crystal oscillator unit to form the moisture-sensitive film 203, which absorbs moisture from the environment.

[0071] Processing and manufacturing of the S3 temperature measurement unit: A platinum resistor is deposited on the non-electrode area of ​​the quartz wafer using a MEMS process. A lead plate is deposited on each end of the platinum resistor to connect to an external temperature measurement circuit. A layer of insulating material is applied to the surface of the platinum resistor to prevent a short circuit between the platinum resistor and the quartz electrode area due to condensation on the surface when measuring humidity.

[0072] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0073] The above are only preferred embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A dual-channel resonant temperature and humidity sensor chip, characterized in that: include: A quartz wafer substrate, on which a working crystal oscillator unit, a reference crystal oscillator unit, and a temperature measurement unit are formed, wherein: The working crystal oscillator unit includes a working electrode, a moisture-sensitive film arranged on the working electrode, and an electrode epitaxial region connected to the working electrode; The reference crystal oscillator unit includes a reference electrode and an electrode epitaxial region connected to the reference electrode; The temperature measuring unit includes a temperature measuring element, a lead epitaxial region and an insulating layer, wherein the lead epitaxial region connects two ends of the temperature measuring element; the insulating layer covers the temperature measuring element and the lead epitaxial region; The working crystal oscillator unit and the reference crystal oscillator unit respectively generate vibrations under the excitation of the driving circuit to output amplitude signals and frequency signals, and the temperature measuring unit outputs resistance signals.

2. The dual-channel resonant temperature and humidity sensor chip according to claim 1, wherein the working crystal oscillator unit comprises working electrodes disposed on the upper and lower surfaces of the quartz wafer substrate, the humidity-sensing film disposed on the working electrodes, and electrode epitaxial regions disposed on the upper and lower surfaces of the quartz wafer substrate and connected to the working electrodes; The reference crystal oscillator unit includes the reference electrodes arranged on the upper and lower surfaces of the quartz wafer substrate and the electrode epitaxial regions arranged on the upper and lower surfaces of the quartz wafer substrate and connected to the reference electrodes.

3. The dual-channel resonant temperature and humidity sensor chip according to claim 1, characterized in that: The material of the crystal oscillator unit electrode is a gold electrode or a silver electrode.

4. The dual-channel resonant temperature and humidity sensor chip according to claim 1, characterized in that: The material of the moisture-sensitive film includes any one of graphene oxide, graphyne, carbon nanotubes, chitosan and cellulose.

5. The dual-channel resonant temperature and humidity sensor chip according to claim 1, characterized in that: The temperature measuring element in the temperature measuring unit is a platinum resistor.

6. The dual-channel resonant temperature and humidity sensor chip according to claim 5, characterized in that: The quartz wafer substrate is disc-shaped, and the surfaces of the working electrode and the reference electrode are both circular; the platinum resistor is located at a position close to the center of the substrate on the perpendicular line between the centers of the working electrode and the reference electrode, and its length direction is parallel to the line connecting the centers of the working electrode and the reference electrode.

7. The dual-channel resonant temperature and humidity sensor chip according to claim 1, characterized in that: The insulating layer is made of silicon nitride.

8. The dual-channel resonant temperature and humidity sensor chip according to claim 1, characterized in that: The working electrode and the reference electrode are symmetrically arranged at the center of the semicircle on both sides of the quartz wafer substrate relative to the center of the circle of the quartz wafer substrate; And / or, the lead extension regions on both sides of the temperature measuring element do not block the central axis of the quartz wafer substrate.

9. A dual-channel resonant temperature and humidity sensing system, characterized by: A dual-channel resonant temperature and humidity sensor chip comprising the above-mentioned claim 5 or 6, further comprising a dual-channel driving circuit, a temperature measurement circuit and a temperature-frequency compensated humidity measurement circuit, wherein the first channel of the dual-channel driving circuit is connected to the epitaxial region of the working electrode, and the second channel of the dual-channel driving circuit is connected to the epitaxial region of the reference electrode, so that the quartz wafer resonates through its own piezoelectric effect; the temperature measurement circuit is connected to the epitaxial region of the lead electrode of the temperature measuring unit in the temperature and humidity sensor chip to measure the resistance; and the temperature-frequency compensated humidity measurement circuit is respectively connected to the electrode epitaxial region of the working electrode and the electrode epitaxial region of the reference electrode.

10. A dual-channel resonant temperature and humidity sensor chip processing method, characterized by: Processing a dual-channel resonant temperature and humidity sensor chip according to any one of claims 1 to 8 comprises the following steps: Quartz crystal processing: The chip substrate is processed by mechanical processing. The quartz crystal rod is oriented by X-ray and then cut into quartz wafers. The cut quartz wafers are polished and processed in size and shape to complete the chip substrate processing. Processing and manufacturing of the crystal oscillator unit: The working crystal oscillator unit and the reference crystal oscillator unit are processed on the upper and lower surfaces of a thickness-sheared quartz wafer using an evaporation process. The working electrode and the reference electrode are composed of circular gold or silver-plated electrodes. Each side of the working electrode and the reference electrode is plated with an electrode epitaxial region for lead wires. The prepared humidity-sensing material is deposited on the working electrode to form a humidity-sensing film. Processing and manufacturing of the temperature measurement unit: A platinum resistor is deposited on the non-electrode area of ​​the quartz wafer through the MEMS process. A lead plate is deposited at both ends of the platinum resistor as a lead epitaxial area, and a layer of insulating material is coated on the surface of the platinum resistor.

Images