Thin film multi-parameter measurement chip and measurement method

Abstract

The invention discloses a film multi-parameter measurement chip and a measurement method, and belongs to the technical field of material physical property measurement. Comprising a chip frame provided with a suspended film window, the suspended film window is covered with a supporting film, the supporting film is provided with a first thermometer, a second thermometer, a third thermometer and a thermoelectric voltage high-temperature measuring end, and the first thermometer serves as a heater and is located on the central symmetry axis of the suspended film window; the chip frame is provided with four conductivity measuring ends surrounding the suspended film window, and wire terminals connected with the thermometers and the conductivity measuring ends. The surface of the electrode structure is covered with an insulating layer, and the insulating layer is provided with through holes exposing the conductive layer corresponding to the thermoelectric voltage high-temperature measuring end, the conductivity measuring end and the wire wiring end. By adopting the measuring chip and the measuring method provided by the invention, the single suspended film simplifies the chip manufacturing process, multi-parameter measurement can be completed by one round of the same sample, the chip configuration adaptability is high, the measurement is accurate and efficient, and errors caused by sample differences are reduced.

Description

Technical Field

[0001] This invention relates to the field of material physical property measurement technology, and in particular to a thin film multi-parameter measurement chip and measurement method. Background Technology

[0002] The evaluation of the thermoelectric properties of functional thin films requires the comprehensive measurement of parameters such as in-plane thermal conductivity, in-plane thermoelectric potential, in-plane electrical conductivity, and Hall coefficient. In existing technologies, different physical parameters need to be measured separately on multiple samples using different measuring devices, which is not only inefficient but also prone to errors due to individual sample differences or changes in the testing environment. Using a multi-parameter measurement chip is one way to solve the above difficulties, but existing chips either use a double suspended film window design, which has a complex manufacturing process and high cost, or lack integrated measurement functions for multiple key parameters. In addition, traditional steady-state thermoelectric potential measurement methods suffer from high signal noise and poor measurement accuracy when characterizing high-resistivity or low-thermoelectric potential samples, which reduces the reliability of the measurement. Summary of the Invention

[0003] The purpose of this invention is to provide a thin-film multi-parameter measurement chip and measurement method to solve the above-mentioned technical problems.

[0004] To achieve the above objectives, the present invention provides a thin-film multi-parameter measurement chip and measurement method, comprising a chip frame with a suspended film window, the suspended film window being covered by a support film, the support film being provided with a first thermometer, a second thermometer, a third thermometer and a thermoelectric voltage high-temperature measuring terminal, the first thermometer also serving as a heater and located on the central symmetrical axis of the suspended film window; the chip frame having four conductivity measuring terminals surrounding the suspended film window, and wire terminals connecting each thermometer and conductivity measuring terminal; the electrode structure surface being covered with an insulating layer, the insulating layer having through holes exposing the conductive layer at the thermoelectric voltage high-temperature measuring terminal, the conductivity measuring terminal and the wire terminals.

[0005] A measurement method for a thin-film multi-parameter measurement chip includes the following steps: Step 1: Deposit the film to be tested on the surface of the measurement chip using a cutout mask, so that the film to be tested covers the suspended film window and forms electrical contact with the thermoelectric voltage high-temperature measurement terminal and the four conductivity measurement terminals; Step 2: Pass an AC heating current with an angular frequency of ω into the first thermometer, and detect the temperature fluctuation amplitude and phase of the first thermometer, as well as the temperature fluctuation phase of the second thermometer. Combine this with the pre-measured thermophysical parameters and thickness of the blank film. and composite film thickness Calculate the in-plane thermal conductivity of the thin film under test. In-plane thermal diffusivity and volumetric heat capacity To complete the measurement of thermophysical parameters; Step 3: Connect the constant current source to the two current terminals of the first thermometer, and connect the resistance measuring device to the third thermometer through the third set of wire terminals. Use any one of the conductivity measuring terminals as the low-temperature thermoelectric voltage measuring terminal. Connect the high-temperature thermoelectric voltage measuring terminal and the low-temperature thermoelectric voltage measuring terminal of the thermoelectric voltage measuring device to complete the in-plane thermoelectric potential measurement. Step 4: Using the van der Pauw method, measure the in-plane resistivity ρ, in-plane conductivity σ, and Hall coefficient of the thin film under test using four conductivity measurement terminals. The electrical parameters are measured, where the in-plane resistivity ρ is defined by the following formula: ; in, It is the thickness of the film to be measured; and These are the resistance parameters measured under two different combinations of current and voltage terminals; In-plane conductivity The formula is: ; Hall coefficient The formula is: ; in, The average value of the Hall voltage. , , , Hall voltages under different current and magnetic field directions. The magnetic flux density is perpendicular to the surface of the thin film. This represents the amplitude of the applied current.

[0006] Therefore, the present invention, employing the aforementioned thin-film multi-parameter measurement chip and measurement method, has the following beneficial effects: 1. The chip adopts a single suspended film window structure, which simplifies the manufacturing process and reduces the manufacturing difficulty and cost compared with the double suspended film design. At the same time, it integrates multiple measurement structures, providing a reliable platform for multi-parameter integrated measurement.

[0007] 2. The chip, in conjunction with the measurement method, can complete the measurement of multiple parameters (in-plane thermal conductivity, in-plane thermal diffusivity, volumetric heat capacity), in-plane thermoelectric potential, and electrical parameters (in-plane conductivity, Hall coefficient) on the same sample in one round of testing, avoiding errors caused by multiple samples or multiple rounds of testing, and significantly improving measurement efficiency and result reliability.

[0008] 3. Thermoelectric potential measurement provides both DC and AC modes. The AC mode can effectively reduce signal noise for high-resistivity or low-thermoelectric potential samples, improve the measurement accuracy of such samples, and broaden the measurement range.

[0009] 4. The chip is configured in two types: Type A (insulated + fifth set of terminals) and Type B (short wire connection). Type A can perform simultaneous temperature measurement and thermoelectric voltage detection, while Type B achieves time-sharing measurement through switch switching, adapting to different measurement scenarios and enhancing the applicability of the solution.

[0010] 5. The measurement process is simple and efficient, and the accuracy and repeatability of each parameter measurement are further improved through the design of vacuum environment measurement, four-terminal wiring, and switching between magnetic field and current direction.

[0011] 6. The through-hole design of the insulating layer ensures stable electrical contact between the film under test and the measuring end, guaranteeing the reliability of the measurement results.

[0012] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0013] Figure 1 This is a top view of the A-type measuring chip of the present invention; Figure 2 This is a partial enlarged view of the suspended membrane window of the Type A measuring chip of the present invention; Figure 3 This is a cross-sectional view of the Type A measuring chip of the present invention; Figure 4 This is a top view of the B-type measurement chip of the present invention; Figure 5 This is a partial enlarged view of the suspended membrane window of the B-type measurement chip of the present invention; Figure 6 This is a cross-sectional view of the B-type measurement chip of the present invention; Figure 7 This is a top view of the A-type measurement chip of the present invention, on which the thin film to be tested has been deposited. Figure 8 This is a cross-sectional view of a type A measurement chip with a thin film to be tested deposited according to the present invention. Figure 9 The figure shows the simulation results of the thermal property measurement process of the thin film I under test based on the A-type measurement chip of the present invention, wherein (a) is the normalized temperature fluctuation amplitude on the first thermometer. The trend graphs of frequency variation are shown in (b), which is a graph showing the relationship between the phase of temperature fluctuations and frequency on the first and second thermometers; (c) is a graph showing the intermediate process of calculating the in-plane thermal conductivity of the two thin film structures using the slope method; and (d) is a graph showing the intermediate process of calculating the in-plane thermal diffusivity of the two thin film structures using the slope method. Figure 10The figure shows the simulation results of the in-plane thermoelectric potential measurement process of the thin film under test based on the A-type measurement chip of the present invention. Among them, (a) is the temperature of the third thermometer changing with time in DC measurement mode. and thermoelectric voltage signal The graph (b) shows the measurement mode under AC conditions. and Line graph; Figure 11 This is a top view of the B-type measurement chip of the present invention, on which the thin film to be tested has been deposited. Figure 12 This is a cross-sectional view of a B-type measurement chip with a thin film to be tested deposited according to the present invention. Figure 13 The figure shows the simulation results of the thermal property measurement process of the thin film II under test based on the B-type measurement chip of the present invention, wherein (a) is the normalized temperature fluctuation amplitude on the first thermometer. The trend graphs of frequency variation are shown in (b), which is a graph showing the relationship between the phase of temperature fluctuation and frequency on the first and second thermometers; (c) is a graph showing the intermediate process of calculating the in-plane thermal conductivity of the two thin film structures using the slope method; and (d) is a graph showing the intermediate process of calculating the in-plane thermal diffusivity of the two thin film structures using the slope method. Figure 14 The figure shows the simulation results of the in-plane thermoelectric potential measurement process of the thin film under test based on the B-type measurement chip of the present invention. Among them, (a) is the temperature of the third thermometer changing with time in DC measurement mode. and thermoelectric voltage signal The graph (b) shows the measurement mode under AC conditions. and Line graph; Figure 15 This is a schematic diagram of the measurement of the potential difference between 14d and 14c based on the measurement chip characterization of the in-plane conductivity of the thin film under test according to the present invention. Figure 16 This is a schematic diagram of the measurement of the potential difference between 14a and 14d based on the measurement chip characterization of the in-plane conductivity of the thin film under test according to the present invention. Figure 17 This is a schematic diagram of the device wiring for characterizing the Hall coefficient of the thin film under test based on a measurement chip, according to the present invention. Figure 18 This is a schematic diagram of the device wiring for characterizing the thermophysical properties of the thin film under test based on the measurement chip according to the present invention; Figure 19 This is a schematic diagram of the device wiring for characterizing the in-plane thermoelectric potential of the thin film under test based on a type A measurement chip according to the present invention. Figure 20 This is a schematic diagram showing the resistance change of the third thermometer used in the present invention to characterize the in-plane thermoelectric potential of the thin film based on a B-type measurement chip. Figure 21 This is a schematic diagram of the wiring for measuring the thermoelectric voltage change of the film under test based on the B-type measurement chip of the present invention, which characterizes the in-plane thermoelectric potential of the film under test.

[0014] Figure Labels 1. Measuring chip; 1a. Type A measuring chip; 1b. Type B measuring chip; 2. Chip frame; 3. Suspended membrane window; 4. Support membrane; 5. First thermometer; 6. Second thermometer; 7. Third thermometer; 8. Thermoelectric voltage high-temperature measuring terminal; 9. Conductivity measuring terminal; 9a. First conductivity measuring terminal; 9b. Second conductivity measuring terminal; 9c. Third conductivity measuring terminal; 9d. Fourth conductivity measuring terminal; 10. Wire connection terminal; 11. First group of wire connection terminals; 11a. First group 11b, First terminal of the first group of wires; 11c, Third terminal of the first group of wires; 11d, Fourth terminal of the first group of wires; 12, Terminals of the second group of wires; 12a, First terminal of the second group of wires; 12b, Second terminal of the second group of wires; 12c, Third terminal of the second group of wires; 12d, Fourth terminal of the second group of wires; 13, Terminals of the third group of wires; 13a, First terminal of the third group of wires; 13b, Second terminal of the third group of wires; 13 c. Third terminal of the third group of wires; 13d. Fourth terminal of the third group of wires; 14. Terminal of the fourth group of wires; 14a. First terminal of the fourth group of wires; 14b. Second terminal of the fourth group of wires; 14c. Third terminal of the fourth group of wires; 14d. Fourth terminal of the fourth group of wires; 15. Terminal of the fifth group of wires; 16. Insulating layer; 17. Thin film under test; 18. Constant current source; 19. Voltmeter; 20. Third harmonic signal acquisition box; 21. Input of the third harmonic signal acquisition box. 21. Terminal; 22. Third harmonic signal output terminal; 23. Reference signal output terminal; 24. Second harmonic signal acquisition box; 25. Input terminal of second harmonic signal acquisition box; 26. Second harmonic signal output terminal; 27. Synchronous data acquisition card; 28. Control module; 29. ​​Sampling resistor; 30. First amplifier; 31. Second amplifier; 32. Switch; 32a. First switch; 32b. Second switch; 32c. Third switch; 32d. Fourth switch; 32e. Fifth switch; 32f. Sixth switch. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages disclosed in the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0016] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0017] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0018] like Figures 1-21 As shown, the present invention provides a thin-film multi-parameter measurement chip and measurement method. Embodiment 1 is a specific implementation of the type A measurement chip 1a: This invention provides a type A measuring chip 1a, the core structure of which is as follows: A single square / rectangular suspended film window 3 (single suspended film design simplifies the process) is provided on the chip frame 2 (single crystal silicon material), and the window is covered with a silicon nitride insulating support film 4. A first thermometer 5, a second thermometer 6, a third thermometer 7, and a thermoelectric voltage high-temperature measuring end 8 are arranged on the surface of the support film 4. The first thermometer 5 also serves as a heater and is located on the central axis of symmetry of the suspended film window 3. The second thermometer 6 is located on one side of it, and the third thermometer 7 and the thermoelectric voltage high-temperature measuring end 8 are located on the other side. The three are arranged parallel to each other. The temperature measuring section of the third thermometer 7 has a tortuous coiled structure, which semi-encloses the outer periphery of the thermoelectric voltage high-temperature measuring end 8 to ensure accurate detection of the temperature of the measuring end, and the two are mutually insulated (core feature of the type A configuration).

[0019] The chip frame 2 has four conductivity measurement terminals 9 (conductivity measurement terminal 9a, conductivity measurement terminal 9b, conductivity measurement terminal 9c, and conductivity measurement terminal 9d) surrounding the suspended membrane window 3, distributed at the four vertices of the same square. Five sets of wire terminals 10 are located around the periphery of the chip frame 2: the first set of wire terminals 11, the second set of wire terminals 12, and the third set of wire terminals 13 are connected to the three thermometers respectively; the fourth set of wire terminals 14 is connected to the four conductivity measurement terminals 9 respectively; each set contains four terminals (two terminals for current and the other two for voltage, achieving four-terminal measurement); the fifth set of wire terminals 15 is a single terminal specifically connected to the thermoelectric voltage high-temperature measurement terminal 8 (unique to type A). An insulating layer 16, consisting of silicon nitride, silicon dioxide, or aluminum oxide, covers the chip surface. Through-holes are provided at the thermoelectric voltage high-temperature measurement terminal 8, four conductivity measurement terminals 9, and all wire connection terminals 10, exposing the conductive layer to ensure stable electrical contact with the film under test 17 and external equipment. The conductive layer is made of elemental materials such as platinum or gold, or alloy materials such as niobium nitride. After the film under test 17 is deposited, it completely covers the suspended film window 3 and forms electrical contact with the aforementioned measurement terminals. Finite element simulation verifies the reliability of the type A measurement chip in terms of thermophysical properties and thermoelectric potential measurement. The physical property parameters and film thickness used in the simulation are shown in Tables 1 and 2. Table 1. Physical properties and thicknesses set for the supporting membrane, insulating layer, and thin film under test in finite element simulation.

[0020] Table 2. Physical property parameters set for the platinum conductive layer and single-crystal silicon in finite element simulation.

[0021] In the simulation model, the size of the suspended membrane window 3 is 1mm × 1mm, the linewidth of the three thermometer measuring sections is 2.5μm, and the distance D between the first thermometer 5 and the second thermometer 6 is 50μm. The ambient temperature and the temperature of the bottom surface of the chip frame 2 are set to 300K; the parameters listed in Tables 1 and 2 do not change with temperature during the simulation, and the parameters of the film under test I listed in Table 1 are assigned to the film under test 17 in the simulation model. A sinusoidal heating current is applied to the first thermometer 5, and the temperature fluctuation information of the first thermometer 5 and the second thermometer 6 is collected, including the amplitude of the temperature fluctuation on the first thermometer 5. and phase Phase of temperature fluctuation on the second thermometer 6 The thermophysical parameters of the suspended thin film structure are calculated. Taking a blank film as an example, based on the one-dimensional heat conduction model, the following two formulas can be obtained: ; ; in, , , This represents the power generated per unit length of the heater; , and d M These are the in-plane thermal conductivity, in-plane thermal diffusivity, and thickness of the blank film (insulating layer 16 + supporting film 4). Normalized temperature fluctuation amplitude ( , Plotting the thermal power applied per unit cross-sectional area perpendicular to the heat flow direction, the in-plane thermal conductivity of the blank film can be obtained from the slope. ; Pair ω Plot the graph; the in-plane thermal diffusivity of the blank film can be obtained from the slope. Volumetric heat capacity of the blank membrane According to Calculated.

[0022] In the following simulation, the test film is deposited on the measurement chip, and the above steps are repeated to obtain the in-plane thermal conductivity of the composite film (test film 17 + insulating layer 16 + support film 4). In-plane thermal diffusivity and volumetric heat capacity Based on the thermophysical parameters and thicknesses of the blank film and the composite film, the in-plane thermal conductivity of the film to be tested 17 can be calculated. In-plane thermal diffusivity and volumetric heat capacity .

[0023] In the simulation of the thermoelectric potential measurement process, a DC or sinusoidal heating current with an angular frequency of ω is passed through the first thermometer 5, and the temperature of the third thermometer 7 is collected as a function of time. And the thermoelectric voltage signal between the high-temperature thermoelectric voltage measuring terminal 8 and the low-temperature thermoelectric voltage measuring terminal. The in-plane thermoelectric potential of the thin film I under test is solved in DC / AC mode. The formula for calculating the in-plane thermoelectric potential in DC mode is as follows: ; in, The thermoelectric potential of the conductive layer material constituting the high-temperature and low-temperature thermoelectric voltage measurement terminals needs to be measured and simulated separately in the experiment. When adopted =-4.96μV / K; For chip frame temperature =300K); The average temperature value is taken from the third thermometer's 7-temperature measurement segment under steady-state conditions. This represents the steady-state thermoelectric voltage. In AC mode, the temperature fluctuation amplitude of the third thermometer with an angular frequency of 2ω at steady state is extracted from the simulation results. and phase Thermoelectric voltage fluctuation amplitude with angular frequency of 2ω and phase The formula for calculating the internal thermoelectric potential under AC mode is: ; Among them, if , If the sign of the first term is negative, then... , The first term is positive, meaning it is negative when the phase difference is 0° and positive when it is 180°.

[0024] The errors (theoretical measurement errors) between the simulated parameters of the thin film I and the actual values ​​(simulation input values) are all less than 5%. The simulation results are shown in Tables 3 and 4. Table 3 Simulation results and comparison with actual values ​​of the thermal property measurement process of the thin film under test (I) based on the type A measurement chip (300K)

[0025] Table 4. Simulation results and comparison with actual values ​​of the in-plane thermoelectric potential measurement process of the thin film under test based on the type A measurement chip (300K)

[0026] Example 2 is a specific implementation of the B-type measurement chip 1b: This invention provides a type B measuring chip 1b, whose structure is basically the same as that of the type A measuring chip 1a (single suspended film window 3, thermometer and conductivity measuring end 9 are arranged in the same way). The core difference is that the thermoelectric voltage high temperature measuring end 8 is directly connected to the third thermometer 7 through a short conductive wire, eliminating the need for a separate fifth set of wire terminals 15. The chip frame 2 only has four sets of wire terminals 10 (the first to the fourth set), simplifying the wiring design.

[0027] Finite element simulation can verify the reliability of the B-type measurement chip in terms of thermal properties and thermoelectric potential measurement. The physical property parameters and thickness used in the simulation are shown in Tables 1 and 2. The parameters in the tables do not change with temperature during the simulation. The parameters of the film to be tested II listed in Table 1 are assigned to the film to be tested 17 in the simulation model. The simulation operation of the thermal physical parameter measurement process of the film to be tested is the same as in Example 1. When simulating the thermoelectric potential measurement process, since the third thermometer 7 is electrically connected to the high-temperature thermoelectric voltage measurement terminal 8, the temperature measurement of the third thermometer 7 and the film thermoelectric voltage detection need to be completed step by step. Finally, the error (theoretical measurement error) between the parameters of the film to be tested II obtained by simulation and the true value is less than 5%. The simulation results are shown in Tables 5 and 6. Table 5. Simulation results and comparison with actual values ​​of the thermophysical property measurement process of the thin film under test II based on the B-type measurement chip (300K)

[0028] Table 6 Simulation results and comparison with actual values ​​of the in-plane thermoelectric potential measurement process of the thin film under test based on the B-type measurement chip (300K)

[0029] The results show that the B-type measurement chip 1b meets the accuracy requirements for multi-parameter measurement and is suitable for different application scenarios.

[0030] Example 3 illustrates a specific implementation method for in-plane conductivity measurement: Using the van der Pauw method, taking type A measuring chip 1a as an example (type B is similar): After depositing the thin film to be tested 17, a constant current source 18 and a voltmeter 19 are connected through the fourth set of wire terminals 14 (including the first terminal 14a, the second terminal 14b, the third terminal 14c, and the fourth terminal 14d of the fourth set of wires). First, current is passed through the first terminal 14a and the second terminal 14b of the fourth set of wires as current terminals, and the third terminal 14c and the fourth terminal 14d of the fourth set of wires as voltage terminals to measure the potential difference and calculate the resistance parameter R. A Then switch the current and voltage terminal combinations and calculate the resistance parameter R. B Substituting into the formula for calculating in-plane resistivity ρ, the in-plane conductivity σ is the reciprocal of ρ, thus achieving accurate measurement of in-plane conductivity. The in-plane resistivity ρ is obtained by solving the following formula: ; in, It refers to the film thickness; in-plane conductivity. The formula is: .

[0031] Example 4 illustrates a specific implementation method for measuring the Hall coefficient: Using the van der Pauw method, taking type A measuring chip 1a as an example (type B is similar): After depositing the test film 17, a magnetic field is applied perpendicular to the film surface. A constant current source 18 is connected through the diagonal terminals of the fourth set of wires 14 (e.g., the first terminal 14a and the third terminal 14c of the fourth set of wires) to supply current. A voltmeter 19 is connected to the other diagonal terminal (the second terminal 14b and the fourth terminal 14d of the fourth set of wires) to measure the Hall voltage. By changing the current polarity and the magnetic field direction, multiple sets of Hall voltage data are collected to calculate the average Hall voltage V. H Substitute the Hall coefficient R H The calculation formula for the Hall coefficient is used to complete the measurement of the Hall coefficient. The formula is: ; in, The magnetic flux density is perpendicular to the surface of the thin film. The amplitude of the applied current; , , , The Hall voltages represent different current and magnetic field directions, where, The Hall voltage between terminals 14b and 14d of the conductor is given by a positive magnetic field and a positive current (current input from terminal 14a and output from terminal 14c). The Hall voltage between terminals 14d and 14b of the conductor under positive magnetic field and reverse current conditions is given by the corresponding... and These represent the Hall voltages corresponding to forward and reverse currents under reverse magnetic field conditions, respectively.

[0032] Example 5 illustrates a specific implementation method for measuring thermophysical properties: Taking the type A measuring chip 1a as an example (type B is similar): the core utilizes the parallel arrangement of the first thermometer 5 (which also serves as a heater) and the second thermometer 6, and employs a known measuring device to measure thermophysical parameters. This measuring device includes a third-harmonic signal acquisition box 20, a second-harmonic signal acquisition box 24, a synchronous data acquisition card 27, and a control module 28. The blank chip is placed in a vacuum environment (the vacuum level of the vacuum environment is better than 1×10⁻⁶). -2Connect the first thermometer 5 to the input terminal 21 of the third harmonic signal acquisition box 20, and connect the second thermometer 6 to the input terminal 25 of the second harmonic signal acquisition box 24. Connect the third harmonic signal output terminal 22, the reference signal output terminal 23, and the second harmonic signal output terminal 26 to multiple input terminals of the synchronous data acquisition card 27, respectively. Apply an AC heating current with an angular frequency of ω to the first thermometer 5. Periodic heat waves propagate along the in-plane direction of the blank film (insulating layer 16 + supporting film 4). Collect the temperature fluctuation amplitude and phase of the first thermometer 5, the temperature fluctuation phase of the second thermometer 6, and combine this with the blank film thickness. Calculate the thermophysical parameters of the blank film; after depositing the test film 17, repeat the above measurement process to obtain the thermophysical parameters of the composite film (test film 17 + insulating layer 16 + support film 4), and then calculate the thermophysical parameters of the test film 17 using the formula, where the in-plane thermal conductivity is... The formula is: ; in, and The thicknesses of the film under test, the blank film, and the composite film are respectively. The in-plane thermal conductivity of the composite film is... The in-plane thermal conductivity of the blank film; the volumetric heat capacity. The formula is: ; in, The volumetric heat capacity of the composite membrane. The volumetric heat capacity of the blank film; in-plane thermal diffusivity. The formula is: .

[0033] Example 6 is an in-plane thermoelectric potential measurement based on type A measurement chip 1a: Supports both DC and AC modes: the first thermometer 5 serves as the heating source, the third thermometer 7 detects the temperature of the high-temperature thermoelectric voltage measuring terminal 8, and any conductivity measuring terminal 9 (such as the fourth conductivity measuring terminal 9d) serves as the low-temperature thermoelectric voltage measuring terminal. During circuit connection, the constant current source 18 is connected to the current terminal of the first thermometer 5. The second harmonic signal acquisition box 24, serving as the resistance measuring device, is connected to the third thermometer 7 via the third set of wire terminals 13. The positive terminal of the second amplifier 31, serving as the input terminal of the thermoelectric voltage measuring device, is connected to the high-temperature thermoelectric voltage measuring terminal 8 via the fifth set of wire terminals 15, and the negative terminal is connected to the low-temperature thermoelectric voltage measuring terminal via the fourth set of wire terminals 14.

[0034] Specifically, in DC mode, a DC heating current is applied to the first thermometer 5, the resistance value of the third thermometer 7 is measured, and the value is converted into a temperature T. S3The temperature T0 and thermoelectric voltage of the chip frame 2 were collected. Calculate the in-plane thermoelectric potential In AC mode, an AC heating current with an angular frequency of ω is passed through the first thermometer 5, and the temperature fluctuation amplitude with an angular frequency of 2ω is collected from the third thermometer 7. With phase and the amplitude of thermoelectric voltage fluctuations With phase The fundamental frequency voltage signal is extracted from both ends of the sampling resistor 29 and amplified by the first amplifier 30, serving as the phase reference signal for the aforementioned thermoelectric voltage signal and temperature fluctuation signal, to calculate the in-plane thermoelectric potential. ; Since the thermoelectric voltage high-temperature measuring terminal 8 of the type A chip is insulated from the third thermometer 7, temperature measurement and thermoelectric voltage detection can be completed simultaneously.

[0035] Example 7 is an in-plane thermoelectric potential measurement based on the B-type measurement chip 1b: The measurement mode is consistent with that of the Type A chip (DC / AC dual mode). The core difference lies in the circuit connection: When connecting the circuit, the second harmonic signal acquisition box 24, acting as the resistance measurement device, needs to be connected to the third thermometer 7 via the first switch 32a, the second switch 32b, the third switch 32c, the fourth switch 32d, and the third set of wire terminals 13. The positive terminal of the second amplifier 31, acting as the input terminal of the thermoelectric voltage measurement device, is connected to the high-temperature thermoelectric voltage measurement terminal 8 via the fifth switch 32e, any one of the third set of wire terminals 13 (such as the second terminal 13b of the third set of wires), and the third thermometer 7. The negative terminal is connected to the low-temperature thermoelectric voltage measurement terminal via the sixth switch 32f and the fourth set of wire terminals 14. Because the third thermometer 7 is electrically connected to the high-temperature thermoelectric voltage measurement terminal 8, the following operations need to be performed in a time-sharing manner by switching the switches: when the first four switches are closed and the last two switches are open, the temperature or temperature fluctuation parameter of the third thermometer 7 is measured; when the first four switches are open and the last two switches are closed, the thermoelectric voltage or thermoelectric voltage fluctuation parameter is measured.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A thin-film multi-parameter measurement chip, characterized in that: The chip frame includes a suspended film window covered by a support film. The support film has a first thermometer, a second thermometer, a third thermometer, and a thermoelectric voltage high-temperature measuring terminal. The first thermometer also functions as a heater and is located on the central axis of symmetry of the suspended film window. The chip frame has four conductivity measuring terminals surrounding the suspended film window, as well as wire terminals connecting the thermometers and conductivity measuring terminals. The electrode structure surface is covered with an insulating layer, and the insulating layer has through holes at the thermoelectric voltage high-temperature measuring terminal, conductivity measuring terminal, and wire terminals to expose the conductive layer.

2. The thin-film multi-parameter measurement chip according to claim 1, characterized in that: The measuring chip includes two configurations: Type A and Type B. In Type A, the thermoelectric voltage high-temperature measuring terminal is insulated from the third thermometer. The chip frame is equipped with a fifth set of wire terminals containing only a single terminal, which is connected to the thermoelectric voltage high-temperature measuring terminal. In Type B, the thermoelectric voltage high-temperature measuring terminal is connected to the third thermometer via a short conductive wire.

3. A thin-film multi-parameter measurement chip according to claim 2, characterized in that: The second thermometer is located on one side of the first thermometer, and the third thermometer and the thermoelectric voltage high-temperature measuring end are located on the other side of the first thermometer. The third thermometer is used to detect the temperature of the thermoelectric voltage high-temperature measuring end, and the first thermometer, the second thermometer, and the third thermometer are arranged in parallel to each other.

4. A thin-film multi-parameter measurement chip according to claim 3, characterized in that: The suspended membrane window has a square or rectangular structure, and the four conductivity measurement ends are distributed at the four vertices of the same square.

5. A thin-film multi-parameter measurement chip according to claim 4, characterized in that: The temperature measuring section of the third thermometer has a zigzag coiled structure and is partially surrounded by the thermoelectric voltage high-temperature measuring end, which is a rectangular or square sheet electrode.

6. A thin-film multi-parameter measurement chip according to claim 5, characterized in that: The wire terminals include four groups, each group containing four terminals. Two of the four terminals are used as current terminals, and the other two are used as voltage terminals. The four groups of wire terminals are electrically connected to the first thermometer, the second thermometer, the third thermometer, and the four conductivity measuring terminals, respectively.

7. A thin-film multi-parameter measurement chip according to claim 6, characterized in that: The conductive layer of the first thermometer, second thermometer, third thermometer, thermoelectric voltage high-temperature measuring end, and conductivity measuring end is made of a single material or an alloy material.

8. A measurement method for a thin-film multi-parameter measurement chip according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: Deposit the film to be tested on the surface of the measurement chip using a cutout mask, so that the film to be tested covers the suspended film window and forms electrical contact with the thermoelectric voltage high-temperature measurement terminal and the four conductivity measurement terminals; Step 2: Pass an AC heating current with an angular frequency of ω into the first thermometer, and detect the temperature fluctuation amplitude and phase of the first thermometer, as well as the temperature fluctuation phase of the second thermometer. Combine this with the pre-measured thermophysical parameters and thickness of the blank film. and composite film thickness Calculate the in-plane thermal conductivity of the thin film under test. In-plane thermal diffusivity and volumetric heat capacity To complete the measurement of thermophysical parameters; Step 3: Connect the constant current source to the two current terminals of the first thermometer. Connect the resistance measuring device to the third thermometer through the third set of wire terminals. Either conductivity measuring terminal can be used as the low-temperature thermoelectric voltage measuring terminal. Connect the high-temperature thermoelectric voltage measuring terminal and the low-temperature thermoelectric voltage measuring terminal of the thermoelectric voltage measuring device to complete the in-plane thermoelectric potential measurement. Step 4: Using the van der Pauw method, measure the in-plane resistivity ρ, in-plane conductivity σ, and Hall coefficient of the thin film under test using four conductivity measurement terminals. The electrical parameters are measured, where the in-plane resistivity ρ is defined by the following formula: ； in, It refers to the film thickness. and These are the resistance parameters measured under two different combinations of current and voltage terminals; In-plane conductivity The formula is: ； Hall coefficient The formula is: ； in, The average value of the Hall voltage. , , , Hall voltages under different current and magnetic field directions. The magnetic flux density is perpendicular to the surface of the thin film. This represents the amplitude of the applied current.

9. The measurement method for a thin-film multi-parameter measurement chip according to claim 8, characterized in that, The specific process of measuring thermophysical parameters in step two is as follows: Under vacuum conditions, the blank measurement chip is measured in advance to obtain the corresponding thermophysical parameters of the blank film; After depositing the thin film to be tested, the measurements are repeated to obtain the corresponding thermophysical parameters of the composite film; Based on the measurement results and thicknesses of the blank film and the composite film, the thermophysical parameters of the film under test are calculated, including the in-plane thermal conductivity of the film under test. The formula is: ； in, and The thicknesses of the film under test, the blank film, and the composite film are respectively. The in-plane thermal conductivity of the composite film is... The in-plane thermal conductivity of the blank film; Volumetric heat capacity The formula is: ； in, The volumetric heat capacity of the composite membrane. The volumetric heat capacity of the blank membrane; In-plane thermal diffusivity The formula is: 。 10. The measurement method for a thin-film multi-parameter measurement chip according to claim 9, characterized in that: Step 3 includes measurements in both DC and AC modes. In the A-type measurement chip, temperature measurement and thermoelectric voltage detection are performed simultaneously, while in the B-type measurement chip, temperature measurement and thermoelectric voltage detection are performed in a time-sharing manner by switching. In DC measurement mode, a DC heating current is applied to the first thermometer. Both type A and type B chips measure the resistance value R of the third thermometer and convert it to obtain the temperature T of the third thermometer. S3 Measure the chip frame temperature T0 and thermoelectric voltage. The formula for calculating the in-plane thermoelectric potential is: ； in, The thermoelectric potential of the conductive layer material constituting the electrode; In AC measurement mode, an AC heating current with an angular frequency of ω is passed into the first thermometer. Both type A and type B chips perform the following measurement: The resistance fluctuation ΔR of the third thermometer with an angular frequency of 2ω is measured. 2ω This is converted into the temperature fluctuation amplitude of the third thermometer. and phase The amplitude of thermoelectric voltage fluctuation at an angular frequency of 2ω was detected. and phase The formula for calculating the in-plane thermoelectric potential is: ； Among them, if , If the sign of the first term is negative, then... , The first item has a positive sign.

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