In-situ integrated measurement method for thermoelectric, rectification and hall effect of micro-nano material

Abstract

The present application relates to the field of data measurement, and discloses a kind of thermoelectric, rectification and Hall effect in-situ integrated measurement method of micro-nano material, the method is applied to thermoelectric, rectification and Hall effect in-situ integrated measurement device, the method comprises: the sample to be measured made of micro-nano material is suspended and placed on the first surface of substrate, the sample to be measured and part of microelectrode contact, the serpentine microelectrode is powered on heating, the thermal performance parameter of the sample to be measured is measured;Constant current source and microelectrode are connected, and the electrical performance parameter of the sample to be measured is measured;Magnetic field is applied, and the Hall thermal effect parameter of the sample to be measured and the Hall effect parameter of the sample to be measured are measured and calculated.The present application directly measures the thermal conductivity, electrical conductivity, Seebeck coefficient, thermoelectric merit value, thermal / electric rectification coefficient, Hall thermal conductivity, carrier concentration and mobility and other parameters of the sample to be measured on one micro-nano material sample, improves the accuracy of measurement result, and lays a foundation for thermoelectric magnetic coupling transport mechanism research.

Description

Technical Field

[0001] This invention relates to the field of data measurement technology, specifically to an in-situ integrated measurement method for thermoelectricity, rectification, and Hall effect of micro / nano materials. Background Technology

[0002] The thermal Hall effect refers to the phenomenon where, when an external magnetic field perpendicular to a temperature gradient is applied to a material with a temperature gradient, hot carriers are deflected, resulting in a heat flow perpendicular to the temperature gradient and creating a transverse temperature difference. In practical measurements of the thermal Hall effect, the effective signal is relatively small compared to the background noise, making experimental measurement quite difficult. Current measurements of the thermal Hall effect mainly focus on macroscopic materials with dimensions on the millimeter scale.

[0003] In current technologies, there is a gap in the in-situ integrated measurement of the thermoelectric, rectification, and Hall properties of micro / nano materials, making it difficult to conduct research on thermo-electromagnetic coupling transport mechanisms. Current experiments primarily employ multiple sample preparations and separate measurements for measuring different properties of micro / nano materials. Using different measurement methods on the same sample to measure its different physical properties can lead to error propagation, further increasing measurement errors and resulting in low accuracy in sample property measurements. Due to limitations in micro / nano technology, existing preparation processes cannot guarantee the consistency of prepared samples, and multiple sample preparations for measuring different properties may cause measurement errors. Summary of the Invention

[0004] In view of this, the present invention provides an in-situ integrated measurement method for thermoelectric, rectification and Hall effects of micro and nano materials, in order to solve the problems of difficulty in measuring the thermal Hall effect of micro and nano materials and the lack of in-situ integrated measurement of thermoelectric, rectification and Hall performance, which makes it difficult to carry out research on thermo-electromagnetic coupling transport mechanism.

[0005] In a first aspect, the present invention provides an in-situ integrated measurement method for thermoelectric, rectification, and Hall effects of micro / nano materials, applied to an in-situ integrated measurement device for thermoelectric, rectification, and Hall effects. The in-situ integrated measurement device includes a substrate and a plurality of serpentine microelectrodes and a plurality of microelectrodes disposed on a first surface of the substrate. The method performs in-situ integrated thermoelectric, rectification, and Hall effect measurements on the same sample under test. The method includes:

[0006] The test sample made of micro-nano materials is suspended on the first surface of the substrate. The test sample is in contact with part of the microelectrode. The serpentine microelectrode is heated by electricity, and a constant current source is connected to the test sample through the microelectrode to measure the thermoelectric performance parameters of the test sample.

[0007] A constant current source and a microelectrode are connected and connected through the sample under test to measure the electrical rectification performance parameters of the sample under test. The serpentine microelectrode is heated by electricity to measure the thermal rectification performance parameters of the sample under test.

[0008] The serpentine microelectrode is heated by electricity, and a magnetic field perpendicular to the heat flow direction is applied. The sample under test generates a thermal Hall effect, producing a transverse temperature difference. The Hall thermal effect parameters of the sample under test are then calculated.

[0009] A constant current source is used to apply current to the sample under test and a magnetic field perpendicular to the current direction. The sample under test generates a Hall effect. The Hall voltage of the sample under test is measured, and the Hall effect parameters of the sample under test are calculated. The Hall thermal effect parameters and the Hall effect parameters constitute the Hall effect measurement results.

[0010] This invention suspends the sample under test on the surface of a substrate, creating a suspended state. A serpentine microelectrode is used to heat the sample, and the thermoelectric and thermal rectification parameters of the sample are measured. After the sample exhibits a thermal Hall effect and a Hall effect, the Hall thermal effect parameters and Hall effect parameters are measured. These parameters are characterized in situ, eliminating the need for multiple sample preparations. This allows for precise in-situ measurement of multiple parameters on a single sample, with no measurement dependency between the parameters, laying the foundation for research on thermo-electromagnetic coupling transport mechanisms.

[0011] In one optional embodiment, the thermoelectric performance parameters include thermal conductivity, electrical conductivity, Seebeck coefficient, and thermoelectric figure of merit, and the measurement of the thermoelectric performance parameters of the sample to be tested includes:

[0012] The heat received by the heat sink of the serpentine microelectrode is measured, and the thermal conductivity of the sample under test is calculated based on the heat received by the heat sink of the serpentine microelectrode.

[0013] Calculate the conductivity of the sample to be tested;

[0014] The Seebeck voltage and the temperature difference of the serpentine microelectrode of the sample under test are measured, and the Seebeck coefficient of the sample under test is calculated based on the Seebeck voltage and the temperature difference of the serpentine microelectrode.

[0015] The absolute temperature of the sample to be tested is measured, and the thermoelectric figure of merit of the sample is calculated based on the absolute temperature, Seebeck coefficient, electrical conductivity, and thermal conductivity.

[0016] This invention reflects the thermoelectric performance parameters of the test sample by measuring its thermal conductivity, electrical conductivity, Seebeck coefficient, and thermoelectric figure of merit.

[0017] In one optional implementation, calculating the conductivity of the sample to be tested includes:

[0018] The cross-sectional area of ​​the sample under test and the spacing of the serpentine microelectrodes were measured by scanning electron microscopy. The voltage of the microelectrodes was measured by a high-impedance voltmeter, and the current of the constant current source was recorded.

[0019] The conductivity of the sample under test is calculated based on the voltage of the serpentine microelectrode, the current of the constant current source, the cross-sectional area of ​​the sample under test, and the spacing between the serpentine microelectrodes.

[0020] This invention calculates the conductivity of a sample under test based on the parameters of the microelectrode, the current parameters of the constant current source, and the parameters of the sample under test, thereby reflecting the conductivity performance of the sample under test.

[0021] In one optional implementation, the steps of connecting the constant current source and the microelectrode, conducting the circuit through the sample under test, measuring the electrical rectification performance parameters of the sample under test, and heating the serpentine microelectrode to measure the thermal rectification performance parameters of the sample under test include:

[0022] Based on the conductivity calculation method, the current input direction is changed, and the electric rectification coefficient of the sample under test is measured and calculated.

[0023] The orientation of the heating end and heat sink end of the serpentine microelectrode was changed, and the thermal rectification coefficient of the sample under test was measured.

[0024] This invention simplifies the calculation of required parameters and facilitates measurement by changing the direction of current input and measuring the rectification coefficient of the sample under test in different directions.

[0025] In one optional implementation, the Hall thermal conductivity parameter is Hall thermal conductivity, and the calculation of the Hall thermal effect parameter of the sample to be tested includes:

[0026] The Hall thermal conductivity of the sample under test is calculated based on the lateral temperature difference and thermal conductivity.

[0027] This invention uses lateral temperature difference and thermal conductivity to calculate the Hall thermal conductivity of the sample under test, so as to reflect the Hall thermal effect of the sample under test.

[0028] In one optional embodiment, the thermoelectric, rectification, and Hall effect in-situ integrated measurement device further includes several electrodes disposed on the first surface of the substrate. The Hall effect parameters include Hall voltage, carrier mobility, and carrier concentration. Measuring the Hall effect parameters of the sample under test includes:

[0029] The electrode in contact with the sample is energized, a magnetic field perpendicular to the current direction is applied to the sample, and the Hall voltage of the sample is measured.

[0030] The charge charge of the charge carriers in the sample to be tested is measured, and the charge carrier concentration of the sample to be tested is calculated based on the charge charge of the charge carriers and the Hall coefficient.

[0031] The carrier mobility of the sample under test is calculated based on the conductivity of the sample under test and the charge of the carriers.

[0032] This invention calculates the carrier concentration of a sample by measuring Hall voltage and the charge of carriers, thereby calculating the carrier mobility.

[0033] In an optional implementation, the method further includes:

[0034] The Hall coefficient of the sample under test is calculated based on the Hall voltage of the sample under test.

[0035] This invention calculates the Hall coefficient of the sample under test based on the Hall voltage of the sample under test, so as to reflect the Hall parameters of the sample under test.

[0036] In a second aspect, the present invention provides an in-situ integrated measurement device for thermoelectricity, rectification, and Hall effect of micro / nano materials, the device comprising:

[0037] The first measurement module is used to suspend the sample to be tested, made of micro-nano materials, on the first surface of the substrate, with the sample to be tested in contact with a part of the microelectrode, to heat the serpentine microelectrode by applying electricity, and to connect the constant current source to the sample to be tested, and to measure the thermoelectric performance parameters of the sample to be tested.

[0038] The second measurement module is used to connect the constant current source and the microelectrode, and to measure the electrical rectification performance parameters of the sample under test by conducting the test through the sample under test, and to measure the thermal rectification performance parameters of the sample under test by heating the serpentine microelectrode.

[0039] The thermal Hall effect generation module is used to heat the serpentine microelectrode by applying an electric current and a magnetic field perpendicular to the heat flow direction. The sample under test generates a thermal Hall effect, producing a lateral temperature difference, and the Hall thermal effect parameters of the sample under test are calculated.

[0040] The third measurement module applies a current to the sample under test through a constant current source and applies a magnetic field perpendicular to the current direction. The sample under test generates a Hall effect, the Hall voltage of the sample under test is measured, and the Hall effect parameters of the sample under test are calculated. The Hall thermal effect parameters and the Hall effect parameters constitute the Hall effect measurement results.

[0041] Thirdly, the present invention provides a computer device, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the in-situ integrated measurement method of thermoelectricity, rectification and Hall effect of micro-nano materials as described in the first aspect or any corresponding embodiment.

[0042] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the in-situ integrated measurement method of thermoelectricity, rectification and Hall effect of micro / nano materials according to the first aspect or any corresponding embodiment described above. Attached Figure Description

[0043] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0044] Figure 1 This is a schematic diagram of an in-situ integrated thermoelectric, rectification, and Hall effect measurement device according to an embodiment of the present invention.

[0045] Figure 2 This is a flowchart illustrating an in-situ integrated measurement method for thermoelectricity, rectification, and Hall effect of micro / nano materials according to an embodiment of the present invention.

[0046] Figure 3 This is a structural block diagram of an in-situ integrated measurement device for thermoelectric, rectification, and Hall effect of micro-nano materials according to an embodiment of the present invention.

[0047] Figure 4 This is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention;

[0048] Explanation of reference numerals in the attached figures:

[0049] 100. Sample to be tested; 11. Detection area; 12. Silicon nitride; 1. First microelectrode; 2. Second microelectrode; 3. Third microelectrode; 4. Fourth microelectrode; 5. Fifth microelectrode; 6. Sixth microelectrode; 7. Seventh microelectrode; 8. Eighth microelectrode. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] In practical measurements of the thermal Hall effect, the effective signal of the thermal Hall effect is relatively small compared to the background noise signal, making experimental measurement of the thermal Hall effect quite difficult. Current measurements of the thermal Hall effect mainly focus on macroscopic materials with dimensions on the millimeter scale.

[0052] In related technologies, there is still a gap in the in-situ integrated measurement of the thermoelectric, rectification, and Hall properties of micro / nano materials. Currently, experimental measurements of different properties of micro / nano materials mainly employ multiple sample preparations and separate measurements. Using different measurement methods on the same sample to measure its different physical properties can cause error propagation, further increasing measurement errors and resulting in low accuracy of sample property measurements. Due to the limitations of micro / nano technology, existing preparation processes cannot guarantee the consistency of prepared samples, and multiple sample preparations for measuring different properties may lead to measurement errors.

[0053] According to an embodiment of the present invention, an embodiment of an in-situ integrated measurement method for thermoelectricity, rectification and Hall effect of micro-nano materials is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0054] This embodiment provides an in-situ integrated measurement method for thermoelectricity, rectification, and Hall effect of micro / nano materials, applied to an in-situ integrated measurement device for thermoelectricity, rectification, and Hall effect, such as... Figure 1 As shown, Figure 1 This is a schematic diagram of an in-situ integrated measurement of thermoelectricity, rectification, and Hall effect. The in-situ integrated measurement includes a substrate, several serpentine microelectrodes disposed on the first surface of the substrate, and several microelectrodes. The sample to be tested 100 is placed in the detection area 11. Figure 1 The silicon nitride 12 in the core forms a temperature homogenizing layer, which effectively controls the temperature and reduces heat loss. The second microelectrode 2 and the sixth microelectrode 6 are serpentine microelectrodes, while the fourth microelectrode 4 and the eighth microelectrode 8 can be serpentine, needle-like, or linear microelectrodes. The first microelectrode 1, the third microelectrode 3, the fifth microelectrode 5, and the seventh microelectrode 7 are all formed into linear structures.

[0055] This method enables in-situ integrated measurement of ten related parameters of thermoelectric properties, rectification effect and Hall effect of thermoelectric materials. Simply place the sample to be tested 100 in the detection area 11 of the detector to achieve in-situ integrated measurement of multiple data, which is convenient for analyzing the coupled transport mechanism of heat-electricity-magnetism.

[0056] Figure 2 This is a flowchart of an in-situ integrated measurement method for thermoelectricity, rectification, and Hall effect of micro / nano materials according to an embodiment of the present invention, as shown below. Figure 2 As shown, the process includes the following steps:

[0057] In step S201, the sample to be tested, made of micro-nano materials, is suspended on the first surface of the substrate. The sample to be tested is in contact with a portion of the microelectrode. The serpentine microelectrode is heated by energizing it, and a constant current source is connected to the sample to be tested through the microelectrode to measure the thermoelectric performance parameters of the sample to be tested.

[0058] In this embodiment of the invention, thermoelectric performance parameters include thermal conductivity, electrical conductivity, Seebeck coefficient, and thermoelectric figure of merit. The sample to be tested is transferred to, for example... Figure 1 On the first surface of the substrate shown, the sample under test is directly connected to the first microelectrode 1, the third microelectrode 3, the fifth microelectrode 5, and the seventh microelectrode 7. The sample under test is not directly connected to the second microelectrode 2, the fourth microelectrode 4, the sixth microelectrode 6, and the eighth microelectrode 8, but is in direct contact with the temperature homogenizing layer formed by silicon nitride. By energizing the first microelectrode 1, the sixth microelectrode 6 acts as a thermal sensor to receive heat conducted from the sample under test, thereby measuring the thermal conductivity parameters of the sample under test.

[0059] In step S202, the constant current source and the microelectrode are connected and the sample under test is turned on to measure the electrical rectification performance parameters of the sample under test. The serpentine microelectrode is heated by energizing to measure the thermal rectification performance parameters of the sample under test.

[0060] In this embodiment of the invention, the thermal rectification performance parameters include the thermal rectification coefficient. By connecting a constant current source and a microelectrode, and by turning on the sample under test and changing the current direction, the thermal rectification performance parameters of the sample under test are measured. The serpentine microelectrode is energized and heated, and the orientation of the heating end and the heat sink end is changed to measure the thermal rectification performance parameters of the sample under test.

[0061] In step S203, the serpentine microelectrode is heated by electricity and a magnetic field perpendicular to the direction of heat flow is applied. The sample under test generates a thermal Hall effect, producing a transverse temperature difference, and the Hall thermal effect parameters of the sample under test are calculated.

[0062] In this embodiment of the invention, the Hall thermal effect parameters include the Hall thermal conductivity of the sample under test. The second microelectrode 2 and the sixth microelectrode 6 serve as the heating end and the heat sink end, respectively, to generate heat flow in the sample under test. At this time, due to the effect of the magnetic field, the sample under test generates a thermal Hall effect and produces a transverse temperature difference, so as to calculate the Hall thermal effect parameters of the sample under test.

[0063] Step S204: Apply current to the sample under test and apply a magnetic field perpendicular to the direction of the sample under test through a constant current source. The sample under test generates a Hall effect. Measure the Hall voltage of the sample under test and calculate the Hall effect parameters of the sample under test.

[0064] The Hall effect thermal parameter and the Hall effect parameter of the sample under test constitute the Hall effect measurement result.

[0065] In this embodiment of the invention, a constant current source is used to apply a current to the sample under test and a magnetic field perpendicular to the direction of the sample under test, causing the sample under test to generate a Hall effect. The Hall voltage of the sample under test can be measured using the first microelectrode 1, the third microelectrode 3, or the fifth microelectrode 5 and the seventh microelectrode 7, so as to calculate the Hall effect parameters of the sample under test.

[0066] The in-situ integrated measurement method for thermoelectric, rectification, and Hall effects of micro / nano materials provided in this embodiment involves suspending the sample under test on the surface of a substrate to form a suspended state. A serpentine microelectrode is used to heat the sample, and the thermoelectric and thermal rectification parameters of the sample are measured. After the sample generates the thermal Hall effect and Hall effect, the Hall thermal effect parameters and Hall effect parameters are measured. The relevant parameters are characterized in-situ without the need for multiple sample preparations, enabling precise in-situ integrated measurement of multiple parameters on the same sample. Furthermore, there is no measurement dependency between the various parameters, laying the foundation for research on thermo-electromagnetic coupling transport mechanisms.

[0067] Specifically, in one embodiment, the measurement of the thermoelectric performance parameters of the sample to be tested in step S201 above includes the following steps:

[0068] Step S2011: Measure the heat received by the heat sink of the serpentine microelectrode, and calculate the thermal conductivity of the sample under test based on the heat received by the heat sink of the serpentine microelectrode.

[0069] Step S2012: Calculate the conductivity of the sample to be tested.

[0070] Step S2013: Measure the Seebeck voltage and the temperature difference of the serpentine microelectrode of the sample to be tested, and calculate the Seebeck coefficient of the sample to be tested based on the Seebeck voltage and the temperature difference of the serpentine microelectrode.

[0071] Step S2014: Measure the absolute temperature of the sample to be tested, and calculate the thermoelectric figure of merit of the sample to be tested based on the absolute temperature, Seebeck coefficient, electrical conductivity and thermal conductivity.

[0072] In this embodiment of the invention, the first microelectrode 1 is heated by an electric current, and the sixth microelectrode 6 acts as a thermal sensor to receive heat conducted from the sample to calculate its thermal conductivity. The homogenization layer rapidly stabilizes the temperatures of the three electrodes on both sides, allowing the second microelectrode 2 and the sixth microelectrode 6 to be used as temperature sensors to calculate the temperature difference. The microelectrode temperature is calculated using the formula for the change in electrode resistance with temperature. The thermal conductivity of the sample is obtained using the following formula:

[0073]

[0074] Where λ is the thermal conductivity of the sample to be tested, Q is the heat flowing through the sample to be tested, ΔT1 is the temperature difference between the second microelectrode 2 and the sixth microelectrode 6 (ΔT1=T1-T6), R2, R′2 and R6, R′6 are the initial resistance of the second microelectrode 2 and the resistance of the sixth microelectrode 6 as a temperature sensor when heated, respectively, and α is the temperature coefficient of resistance of the microelectrode.

[0075] While measuring thermal conductivity, a temperature difference is formed between the first microelectrode 1 and the seventh microelectrode 7. Based on the Seebeck effect of thermoelectric materials, a Seebeck voltage can be obtained across this temperature difference. Therefore, a high-resolution voltmeter is connected to the first microelectrode 1 and the seventh microelectrode 7 to measure the Seebeck voltage. Due to the presence of the temperature homogenizing layer, the temperature difference between the first microelectrode 1 and the seventh microelectrode 7 is also the temperature difference between the second microelectrode 2 and the sixth microelectrode 6. The Seebeck coefficient of the sample under test can be obtained using the following formula:

[0076]

[0077] Where S is the Seebeck coefficient of the sample to be tested, U is the Seebeck voltage of the sample to be tested, and ΔT2 is the temperature difference between the first microelectrode 1 and the seventh microelectrode 7 (ΔT2=T1-T7). The Seebeck coefficient of the sample to be tested can be calculated based on the results of thermal conductivity measurement.

[0078] According to the definition of the thermoelectric figure of merit (ZT), the formula for calculating ZT can be obtained:

[0079]

[0080] Where ZT is the thermoelectric figure of merit and T is the absolute temperature of the sample to be tested.

[0081] The thermal conductivity, electrical conductivity, Seebeck coefficient, and thermoelectric figure of merit of the test sample are measured to reflect the thermoelectric performance parameters of the test sample.

[0082] Specifically, in one embodiment, the calculation of the conductivity of the sample to be tested in step S2012 includes the following steps:

[0083] In step S20121, the cross-sectional area of ​​the sample under test and the spacing of the serpentine microelectrodes are measured by scanning electron microscopy, the voltage of the microelectrodes is measured by a high-impedance voltmeter, and the current of the constant current source is recorded.

[0084] Step S20122: Calculate the conductivity of the sample under test based on the voltage of the serpentine microelectrode, the current of the constant current source, the cross-sectional area of ​​the sample under test, and the spacing of the serpentine microelectrodes.

[0085] In this embodiment of the invention, when measuring conductivity, a constant current source is connected to the first microelectrode 1 and the seventh microelectrode 7, and then the sample under test is used for conduction. A high-impedance voltmeter (V) is then used to connect the third microelectrode 3 and the fifth microelectrode 5 to measure the voltage. The conductivity is calculated using the following formula:

[0086]

[0087] Where σ is the conductivity of the sample under test, ρ is the resistivity of the sample under test, R is the resistance, A is the cross-sectional area of ​​the sample under test, L1 is the distance between the third microelectrode 3 and the fifth microelectrode 5, I is the current of the constant current source, and V1 is the voltage obtained by the high impedance voltmeter.

[0088] The conductivity of the sample under test is calculated based on the parameters of the microelectrode, the current parameters of the constant current source, and the parameters of the sample under test, so as to reflect the conductivity performance of the sample under test.

[0089] Specifically, in one embodiment, step S202 involves connecting the constant current source and the microelectrode, and conducting the circuit through the sample under test to measure the electrical rectification performance parameters of the sample under test. It also involves heating the serpentine microelectrode to measure the thermal rectification performance parameters of the sample under test. The steps include the following:

[0090] Step S2021: According to the conductivity calculation method, change the current input direction and measure and calculate the electric rectification coefficient of the sample under test.

[0091] Step S2022: Change the orientation of the heating end and heat sink end of the serpentine microelectrode, and measure the thermal rectification coefficient of the sample to be tested.

[0092] In this embodiment of the invention, the direction of the constant current source output current is changed, and the conductivity σ′ of the sample under test in different directions is measured, thereby calculating the electric rectification coefficient δ of the sample under test.

[0093]

[0094] By changing the orientation of the heating end and heat sink end of the microelectrode, the thermal conductivity λ and λ′ in different directions can be measured, thereby calculating the thermal rectification coefficient of the sample under test.

[0095]

[0096] Where η is the thermal rectification coefficient of the sample under test, and λ′ is the thermal conductivity in the opposite direction after changing the heating end and heat sink end of the microelectrode.

[0097] By changing the direction of current input, the rectification coefficient of the sample under test in different directions is measured, which simplifies the calculation of the required parameters and facilitates measurement.

[0098] Specifically, in one embodiment, the calculation of the Hall thermal effect parameters of the sample to be tested in step S203 above includes the following steps:

[0099] Step S2031: Calculate the Hall thermal conductivity of the sample to be tested based on the transverse temperature difference and thermal conductivity of the sample to be tested.

[0100] In this embodiment of the invention, when measuring the thermal Hall effect, a magnetic field perpendicular to the sample is applied. The second microelectrode 2 and the sixth microelectrode 6 serve as the heating end and the heated end, respectively, to generate heat flow in the sample. Due to the magnetic field, a thermal Hall effect occurs in the sample, resulting in a lateral temperature difference. The temperatures at both ends of the sample are measured using the fourth microelectrode 4 and the eighth microelectrode 8. The lateral temperature difference (ΔT3 = T4 - T8) caused by the thermal Hall effect can be calculated using the following formula:

[0101]

[0102] Based on the measured transverse temperature difference, the Hall thermal conductivity λ″ of the sample can be calculated using the following formula:

[0103]

[0104] Specifically, in one embodiment, the calculation of the Hall effect parameters of the sample to be tested in step S204 above includes the following steps:

[0105] Step S2041: Apply a magnetic field perpendicular to the current direction to the sample under test, energize the electrode in contact with the sample under test, and measure the Hall voltage of the sample under test.

[0106] Step S2042: Measure the charge of the carriers in the sample to be tested, and calculate the carrier concentration of the sample to be tested based on the charge of the carriers and the Hall coefficient.

[0107] Step S2043: Calculate the carrier mobility of the sample under test based on the conductivity of the sample under test and the charge of the carriers in the sample under test.

[0108] In this embodiment of the invention, the carrier concentration of the sample to be tested is further calculated according to the following formula:

[0109]

[0110] Where e is the charge of the charge carriers in the sample to be tested.

[0111] The carrier concentration of the sample under test is calculated by measuring the Hall voltage and the charge of the carriers, and thus the carrier mobility is calculated.

[0112] Step S405: Calculate the carrier mobility of the sample under test based on the conductivity and charge of the carriers.

[0113] In this embodiment of the invention, the carrier mobility of the sample under test is further calculated according to the following formula:

[0114]

[0115] The carrier concentration of the sample under test is calculated by measuring the Hall voltage and the charge of the carriers, and thus the carrier mobility is calculated.

[0116] Specifically, in one embodiment, the in-situ integrated measurement method for thermoelectricity, rectification, and Hall effect of micro / nano materials provided by the present invention further includes the following steps:

[0117] Step S205: Calculate the Hall coefficient of the sample under test based on the Hall voltage of the sample under test.

[0118] In this embodiment of the invention, when measuring the Hall effect parameters of the sample under test, a current I is passed through the sample under test via the first microelectrode 1 and the seventh microelectrode 7 while a magnetic field perpendicular to the sample is applied. S The Hall voltage V of the sample under test can be measured using the first microelectrode 1, the third microelectrode 3, or the fifth microelectrode 5 and the seventh microelectrode 7. H The Hall coefficient R of the sample to be tested is calculated using the following formula. H :

[0119]

[0120] Where d is the thickness of the sample to be tested, and B is the intensity of the applied magnetic field.

[0121] The Hall coefficient of the sample under test is calculated based on the Hall voltage of the sample under test, which reflects the Hall parameters of the sample under test.

[0122] In addition, the in-situ integrated measurement of thermoelectric, rectification, and Hall effects of micro-nano materials provided in this embodiment measures ten physical parameters at once, and the relevant parameters are characterized in situ without the need for multiple sample preparations, ensuring the reliability and accuracy of the measurement results. The measurement results are more accurate, and there is no measurement dependency between the parameters, so as to analyze the thermo-electric-magnetic coupling transport mechanism. This provides a reliable characterization method for studying the thermoelectric-rectification-Hall coupling mechanism, and the parameters do not have measurement dependency and do not affect each other, thus improving the measurement accuracy.

[0123] This method not only breaks through the limitation of existing technologies that can only be used for measuring the Hall effect of macroscopic materials, but also enables the measurement of the thermoelectric figure of merit of irregularly shaped materials, thus broadening the range of applicable samples. It achieves in-situ integrated characterization of the thermoelectric properties, rectification effect, and Hall effect of micro / nano materials, eliminating the need for multiple measurements using different methods, samples, and equipment. Furthermore, it avoids measurement errors and even erroneous results caused by multiple sample preparations, measurements, and calculations, ensuring accurate and high-precision measurements.

[0124] This embodiment also provides a Hall effect measurement device for micro / nano materials, which is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0125] This embodiment provides an in-situ integrated measurement device for thermoelectricity, rectification, and Hall effect of micro / nano materials, such as... Figure 3 As shown, it includes:

[0126] The first measurement module 301 is used to suspend the sample to be tested, made of micro-nano materials, on the first surface of the substrate, with the sample to be tested in contact with a part of the microelectrode, to heat the serpentine microelectrode by applying electricity, and to connect a constant current source to the sample to be tested, so as to measure the thermoelectric performance parameters of the sample to be tested.

[0127] The second measurement module 302 is used to connect the constant current source and the microelectrode, and to measure the electrical rectification performance parameters of the sample under test by conducting the test through the sample under test, and to measure the thermal rectification performance parameters of the sample under test by energizing and heating the serpentine microelectrode.

[0128] The thermal Hall effect generation module 303 is used to heat the serpentine microelectrode by applying electricity and a magnetic field perpendicular to the heat flow direction, so that the sample under test generates a thermal Hall effect, produces a transverse temperature difference, and calculates the Hall thermal effect parameters of the sample under test.

[0129] The third measurement module 304 applies current to the sample under test through a constant current source and applies a magnetic field perpendicular to the current direction. The sample under test generates a Hall effect, the Hall voltage of the sample under test is measured, and the Hall effect parameters of the sample under test are calculated. The Hall thermal effect parameters and the Hall effect parameters constitute the Hall effect measurement results.

[0130] In some alternative implementations, the first measurement module 301 includes:

[0131] The first calculation unit is used to measure the heat received by the heat sink of the serpentine microelectrode and calculate the thermal conductivity of the sample under test based on the heat received by the heat sink of the serpentine microelectrode.

[0132] The second calculation unit is used to calculate the conductivity of the sample to be tested;

[0133] The third calculation unit is used to measure the Seebeck voltage and the temperature difference of the serpentine microelectrode of the sample under test, and to calculate the Seebeck coefficient of the sample under test based on the Seebeck voltage and the temperature difference of the serpentine microelectrode.

[0134] The fourth calculation unit is used to measure the absolute temperature of the sample under test and calculate the thermoelectric figure of merit of the sample under test based on the absolute temperature, Seebeck coefficient, electrical conductivity and thermal conductivity.

[0135] In some alternative implementations, the second computing unit includes:

[0136] The measurement subunit is used to measure the cross-sectional area of ​​the sample under test and the spacing of the serpentine microelectrodes using a scanning electron microscope, measure the voltage of the microelectrodes using a high-impedance voltmeter, and record the current of the constant current source.

[0137] The calculation subunit is used to calculate the conductivity of the sample under test based on the voltage of the serpentine microelectrode, the current of the constant current source, the cross-sectional area of ​​the sample under test, and the spacing of the serpentine microelectrode.

[0138] In some alternative implementations, the second measurement module 302 includes:

[0139] The first measurement unit is used to measure and calculate the electric rectification coefficient of the sample under test by changing the direction of current input according to the conductivity calculation method.

[0140] The second measurement unit is used to change the orientation of the heating end and the heat sink end of the serpentine microelectrode and to measure the thermal rectification coefficient of the sample under test.

[0141] In some alternative implementations, the thermal Hall effect generating module 303 includes:

[0142] The fifth calculation unit is used to calculate the Hall thermal conductivity of the sample under test based on the transverse temperature difference and thermal conductivity.

[0143] In some alternative implementations, the third measurement module 304 includes:

[0144] The third measurement unit is used to apply a magnetic field perpendicular to the current direction to the sample under test, energize the electrodes in contact with the sample under test, and measure the Hall voltage of the sample under test.

[0145] The sixth calculation unit is used to measure the charge of the charge carriers in the sample to be tested, and to calculate the charge carrier concentration of the sample to be tested based on the charge of the charge carriers and the Hall coefficient.

[0146] The seventh calculation unit is used to calculate the carrier mobility of the sample under test based on the conductivity and charge of the carriers.

[0147] In some alternative embodiments, the device further includes:

[0148] The calculation module is used to calculate the Hall coefficient of the sample under test based on the Hall voltage of the sample under test.

[0149] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0150] In this embodiment, the Hall effect measurement device for micro / nano materials is presented in the form of a functional unit. Here, a unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0151] This invention also provides a computer device having the above-described features. Figure 3 The Hall effect measurement device for micro / nano materials is shown.

[0152] Please see Figure 4 , Figure 4 This is a schematic diagram of the structure of a computer device provided in an optional embodiment of the present invention, such as... Figure 4 As shown, the computer device includes one or more processors 10, memory 20, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 4 Take a processor 10 as an example.

[0153] Processor 10 may be a central processing unit, a network processor, or a combination thereof. Processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0154] The memory 20 stores instructions executable by at least one processor 10 to cause at least one processor 10 to perform the method shown in the above embodiments.

[0155] The memory 20 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 20 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 20 may optionally include memory remotely located relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0156] The memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0157] The computer device also includes an input device 30 and an output device 40. The processor 10, memory 20, input device 30, and output device 40 can be connected via a bus or other means. Figure 4 Taking the example of a connection between China and Israel via a bus.

[0158] Input device 30 can receive input numerical or character information, and generate key signal inputs related to user settings and function control of the computer device, such as a touch screen. Output device 40 may include display devices. These display devices include, but are not limited to, liquid crystal displays, light-emitting diodes (LEDs), displays, and plasma displays. In some alternative embodiments, the display device may be a touch screen.

[0159] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0160] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for in-situ integrated measurement of thermoelectricity, rectification, and Hall effect of micro / nano materials, characterized in that, An integrated in-situ measurement device for thermoelectric, rectification, and Hall effects is applied. The device includes a substrate and several serpentine microelectrodes and several microelectrodes disposed on a first surface of the substrate. The method performs integrated in-situ thermoelectric, rectification, and Hall effect measurements on the same sample under test. The method includes: The sample to be tested, made of micro-nano materials, is suspended on the first surface of the substrate. The sample to be tested is in contact with a portion of the microelectrode, but not in direct contact with the serpentine microelectrode. It is in direct contact with the temperature homogenization layer formed by silicon nitride. The serpentine microelectrode is heated by an electric current, and a constant current source is connected to the sample to be tested through the microelectrode. The thermoelectric performance parameters of the sample to be tested are measured, including thermal conductivity, electrical conductivity, Seebeck coefficient, and thermoelectric figure of merit. A constant current source and a microelectrode are connected and connected through the sample under test to measure the electrical rectification performance parameters of the sample under test. The serpentine microelectrode is heated by electricity to measure the thermal rectification performance parameters of the sample under test. The serpentine microelectrode is heated by electricity, and a magnetic field perpendicular to the direction of heat flow is applied. The sample under test generates a thermal Hall effect, producing a lateral temperature difference. The Hall thermal effect parameter of the sample under test is calculated based on the lateral temperature difference and the thermal conductivity. The Hall thermal effect parameter is the Hall thermal conductivity. A constant current source is used to apply current to the sample under test and a magnetic field perpendicular to the current direction. The sample under test generates a Hall effect. The Hall voltage of the sample under test is measured, and the Hall effect parameters of the sample under test are calculated. The Hall effect parameters include Hall voltage, carrier mobility, and carrier concentration. The Hall thermal effect parameters and the Hall effect parameters constitute the Hall effect measurement results. The process of connecting the constant current source and the microelectrode, and conducting the circuit through the sample under test to measure the electrical rectification performance parameters of the sample under test, and heating the serpentine microelectrode to measure the thermal rectification performance parameters of the sample under test, includes: Based on the conductivity calculation method, the current input direction is changed, and the electric rectification coefficient of the sample under test is measured and calculated. The orientation of the heating end and heat sink end of the serpentine microelectrode was changed, and the thermal rectification coefficient of the sample under test was measured. The thermoelectric, rectification, and Hall effect in-situ integrated measurement device further includes several electrodes disposed on the first surface of the substrate. The calculation of the Hall effect parameters of the sample under test includes: A magnetic field perpendicular to the current direction is applied to the sample under test, and the electrode in contact with the sample under test is energized to measure the Hall voltage of the sample under test. The charge charge of the charge carriers in the sample to be tested is measured, and the charge carrier concentration of the sample to be tested is calculated based on the charge charge of the charge carriers and the Hall coefficient. The carrier mobility of the sample under test is calculated based on the conductivity of the sample under test and the charge of the carriers.

2. The method according to claim 1, characterized in that, The thermoelectric performance parameters include thermal conductivity, electrical conductivity, Seebeck coefficient, and thermoelectric figure of merit. The measurement of the thermoelectric performance parameters of the sample under test includes: The heat received by the heat sink of the serpentine microelectrode is measured, and the thermal conductivity of the sample under test is calculated based on the heat received by the heat sink of the serpentine microelectrode. Calculate the conductivity of the sample to be tested; The Seebeck voltage and the temperature difference of the serpentine microelectrode of the sample under test are measured, and the Seebeck coefficient of the sample under test is calculated based on the Seebeck voltage and the temperature difference of the serpentine microelectrode. The absolute temperature of the sample to be tested is measured, and the thermoelectric figure of merit of the sample is calculated based on the absolute temperature, Seebeck coefficient, electrical conductivity, and thermal conductivity.

3. The method according to claim 2, characterized in that, The calculation of the conductivity of the sample to be tested includes: The cross-sectional area of ​​the sample under test and the spacing of the serpentine microelectrodes were measured by scanning electron microscopy. The voltage of the microelectrodes was measured by a high-impedance voltmeter, and the current of the constant current source was recorded. The conductivity of the sample under test is calculated based on the voltage of the serpentine microelectrode, the current of the constant current source, the cross-sectional area of ​​the sample under test, and the spacing between the serpentine microelectrodes.

4. The method according to claim 1, characterized in that, The method further includes: The Hall coefficient of the sample under test is calculated based on the Hall voltage of the sample under test.

5. A device for in-situ integrated measurement of thermoelectricity, rectification, and Hall effect of micro / nano materials, characterized in that, The device includes: The first measurement module is used to suspend the sample to be tested, made of micro-nano materials, on the first surface of the substrate. The sample to be tested is in contact with a portion of the microelectrode, not in direct contact with the serpentine microelectrode, and in direct contact with the temperature homogenization layer formed by silicon nitride. The serpentine microelectrode is heated by electricity, and a constant current source is connected to the sample to be tested. The thermoelectric performance parameters of the sample to be tested are measured, including thermal conductivity, electrical conductivity, Seebeck coefficient, and thermoelectric figure of merit. The second measurement module is used to connect the constant current source and the microelectrode, and to measure the electrical rectification performance parameters of the sample under test by conducting the test through the sample under test, and to measure the thermal rectification performance parameters of the sample under test by heating the serpentine microelectrode. The thermal Hall effect generation module is used to heat the serpentine microelectrode by applying an electric current and a magnetic field perpendicular to the direction of heat flow. The sample under test generates a thermal Hall effect, producing a lateral temperature difference. The Hall thermal effect parameter of the sample under test is calculated based on the lateral temperature difference and the thermal conductivity. The Hall thermal effect parameter is the Hall thermal conductivity. The third measurement module applies a current to the sample under test through a constant current source and applies a magnetic field perpendicular to the current direction. The sample under test generates a Hall effect, the Hall voltage of the sample under test is measured, and the Hall effect parameters of the sample under test are calculated. The Hall effect parameters include Hall voltage, carrier mobility, and carrier concentration. The Hall thermal effect parameters and the Hall effect parameters constitute the Hall effect measurement results. The second measurement module is specifically used to: change the current input direction according to the conductivity calculation method, measure and calculate the electrical rectification coefficient of the sample under test; change the direction of the heating end and heat sink end of the serpentine microelectrode, and measure the thermal rectification coefficient of the sample under test; The thermoelectric, rectification, and Hall effect in-situ integrated measurement device further includes several electrodes disposed on the first surface of the substrate. The third measurement module is specifically used for: applying a magnetic field perpendicular to the current direction to the sample under test, energizing the electrodes in contact with the sample under test, and measuring the Hall voltage of the sample under test; measuring the charge of the charge carriers in the sample under test, and calculating the charge carrier concentration of the sample under test based on the charge of the charge carriers and the Hall coefficient; and calculating the carrier mobility of the sample under test based on the conductivity of the sample under test and the charge of the charge carriers.

6. A computer device, characterized in that, include: A memory and a processor are interconnected, the memory stores computer instructions, and the processor executes the computer instructions to perform the in-situ integrated measurement method of thermoelectricity, rectification and Hall effect of micro-nano materials as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to execute the in-situ integrated measurement method of thermoelectricity, rectification and Hall effect of micro-nano materials according to any one of claims 1 to 4.

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