First principle screening method and system for thin film thermocouple sensitive material system

Abstract

The invention discloses a first principle screening method and system for a thin film thermocouple sensitive material system, and the method comprises the steps: obtaining a crystal structure of a candidate material, obtaining a standard crystal model from a database, and carrying out the model adjustment according to the actual material selection requirements; the adjusted model is converted into a POSCAR crystal file, self-consistent calculation is carried out after structural optimization convergence, then electronic structure calculation is carried out, and the electronic structure and energy band data of the crystal are obtained; the obtained electronic structure and energy band data are processed, the effective mass, the deformation potential energy and the elastic constant of the sensitive material are obtained based on the deformation potential theory, and the carrier mobility of the material is obtained through calculation; and carrying out thermoelectric calculation on the obtained electronic structure, energy band data and carrier mobility of the material to obtain Seebeck coefficient and conductivity of the sensitive material, and screening out a material with high thermoelectric performance as the sensitive material of the thin film thermocouple. The problems of long experimental period, high experimental cost and experimental errors existing in material selection are solved.

Description

Background Art

[0002] With the development of science and technology, people have higher and higher requirements for temperature measurement. Thin film thermocouples are widely used in aerospace, weapons and equipment, biomedicine and other fields due to their advantages such as fast response time, in-situ measurement, passive sensing and little impact on the object being measured.

[0003] In the current research on thin-film thermocouples, the method of improving the thermoelectric properties of thermocouples, such as the Seebeck coefficient, carrier mobility, and electrical conductivity, has always been the research focus. People have conducted research from multiple aspects such as the preparation process, material selection, and structural design of thermocouples. Among them, the selection of sensitive materials for thin-film thermocouples plays a vital role in the key properties of thermocouples. For a long time, the development of high-performance thermoelectric materials and the optimization of sensitive material systems for thin-film thermocouples have been research hotspots for improving the performance of thermocouples.

[0004] In the selection of sensitive materials for thin-film thermocouples, experimental preparation of material samples, thermoelectric performance tests, and performance evaluation are often used to select materials. Experimental screening methods usually take a lot of time and cost, and factors such as environmental conditions and differences in preparation processes may also affect the results. In addition, it is difficult to accurately consider factors such as interface effects and impurity effects in the experiment, which limits the repeatability and accuracy of experimental data.

[0005] In order to better select thermocouple materials and solve the problems of time-consuming, high-cost and limited accuracy of experimental material screening, a computational simulation method is needed to select the material system of thin-film thermocouples. Based on the theoretical model, a computer is used to simulate the material properties. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a first principles screening method and system for a thin film thermocouple sensitive material system in view of the deficiencies in the above-mentioned prior art, so as to solve the technical problems existing in the current material selection technology such as long experimental cycle, high experimental cost and experimental errors.

[0007] The present invention adopts the following technical solutions: A first principles screening method for a thin film thermocouple sensitive material system comprises the following steps: Obtain the crystal structure of the candidate material, obtain the standard crystal model from the database, and adjust the model according to the actual material selection requirements; The adjusted model is converted into a POSCAR crystal file, and a self-consistent calculation is performed after the structure optimization converges, followed by an electronic structure calculation to obtain the electronic structure and energy band data of the crystal; The obtained electronic structure and energy band data are processed, and the effective mass, deformation potential energy, and elastic constant of the sensitive material are obtained based on the deformation potential theory, and the carrier mobility of the material is calculated; The obtained electronic structure, energy band data, and carrier mobility of the material are used for thermoelectric calculations to obtain the Seebeck coefficient and conductivity of the sensitive material, and materials with high thermoelectric properties are screened out as sensitive materials for thin film thermocouples.

[0008] Preferably, the electronic structure calculation adopts the LDA+U method, where U is the Hubbard-U correction; the parameters are adjusted in the INCAR file, the plane wave cutoff energy is set to 1.3 times the maximum cutoff energy in the pseudopotential file, and the energy convergence criterion is 10 -5 eV, the K-point density is set to above.

[0009] Preferably, the cif file output by materialsstudio is converted into a POSCAR file as the input crystal structure file of VASP through VESTA software, and the subsequent structure optimization and property calculation are all performed using VASP software, using PAW in the projected suffix wave to process the electronic wave function.

[0010] Preferably, the carrier mobility of the material for:

[0011] in, is the reduced Planck constant, is the elastic constant of the crystal in the α direction, e is the electron charge, is the Boltzmann constant, T is the temperature, is the deformation potential energy of the crystal in the α direction, is the effective mass.

[0012] Preferably, the elastic constant, deformation potential energy and effective mass are obtained through the relationship between the energy band of the material and the crystal deformation amount. After applying 1%, 0.5%, -1% and -0.5% deformation in a fixed direction of the crystal model, the crystal structure optimization and electronic structure calculation are performed again to obtain the energy and energy band diagram.

[0013] Preferably, energy data of the bottom of the conduction band or the top of the valence band of the energy band is selected, and the selection basis depends on the properties of the semiconductor material; a quadratic function is fitted to the energy data, and the second-order derivative is calculated to obtain the effective mass; In the deformation potential energy calculation, the relationship between the energy value at the bottom of the conduction band or the top of the valence band and the deformation is fitted, and the first derivative is calculated to obtain the deformation potential energy of the material. The selection of the conduction band and the valence band is determined according to the semiconductor properties of the material. For n-type semiconductors, the conduction band is selected for fitting, and for p-type semiconductors, the valence band is selected for fitting. In the calculation of elastic constants, the relationship between energy and deformation is fitted with a curve, the second derivative is calculated, and then divided by the crystal volume to obtain the elastic constant.

[0014] Preferably, the Seebeck coefficient and conductivity of the sensitive material are obtained as follows: After converting the electronic structure and energy band data, intrans, struct, and energy files are generated as input files. The temperature range, temperature gradient, and calculation accuracy parameters to be calculated for the material are set in the intrans file. After executing the calculation command, the material property file is obtained, and the output trace file is used as the material property data result file; the obtained trace file contains Seebeck coefficient, conductivity / relaxation time, carrier concentration, and temperature data. The conductivity data is obtained by calculating the relaxation time.

[0015] Preferably, the relaxation time is calculated based on deformation potential theory as follows:

[0016] in, is the carrier mobility, is the effective mass and e is the mass of the electron.

[0017] Preferably, the relaxation time is calculated and then multiplied by the conductivity / relaxation time to obtain the conductivity of the material. A graphing software is used to obtain a relationship diagram between the Seebeck coefficient, conductivity, carrier concentration, and temperature of the material, and materials with high Seebeck coefficient, high conductivity, and carrier mobility are comprehensively screened.

[0018] In a second aspect, an embodiment of the present invention provides a first principles screening system for a thin film thermocouple sensitive material system, comprising: The data module obtains the crystal structure of the candidate material, obtains the standard crystal model from the database, and adjusts the model according to the actual material selection requirements; The conversion module converts the adjusted model into a POSCAR crystal file, performs self-consistent calculation after structural optimization convergence, and then performs electronic structure calculation to obtain the electronic structure and energy band data of the crystal; The processing module processes the obtained electronic structure and energy band data, obtains the effective mass, deformation potential energy, and elastic constant of the sensitive material based on the deformation potential theory, and calculates the carrier mobility of the material; The screening module performs thermoelectric calculations on the obtained electronic structure, energy band data, and carrier mobility of the material to obtain the Seebeck coefficient and conductivity of the sensitive material, and screens out materials with high thermoelectric properties as sensitive materials for thin-film thermocouples.

[0019] In a third aspect, a computer device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the first principles screening method for the above-mentioned thin film thermocouple sensitive material system when executing the computer program.

[0020] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, comprising a computer program, which, when executed by a processor, implements the steps of the first-principles screening method for the above-mentioned thin-film thermocouple sensitive material system.

[0021] In a fifth aspect, a chip comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the first principles screening method for the above-mentioned thin film thermocouple sensitive material system when executing the computer program.

[0022] In a sixth aspect, an embodiment of the present invention provides an electronic device, comprising a computer program, which, when executed by the electronic device, implements the steps of the first principles screening method for the above-mentioned thin film thermocouple sensitive material system.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects: A first-principles screening method for thin-film thermocouple sensitive material systems, which selects sensitive materials with high thermoelectric performance for thin-film thermocouples by establishing material crystal structure, structural optimization, intrinsic property calculation, thermoelectric calculation and other processes. There is no need to conduct material selection experiments, and it is not affected by experimental conditions and resource limitations. It can solve the problems of long experimental cycle and high experimental cost in the current material selection technology. The first-principles screening method is mainly based on quantum mechanics, solid state physics, and density functional theory (DFT). It analyzes the electronic structure and band structure of the material, and calculates the thermoelectric performance based on the theoretical basis of lattice structure, electron transport, heat transport, etc. The whole process is implemented by the first-principles calculation software of the computer.

[0024] Furthermore, the electronic structure calculation adopts the LDA+U method. The core purpose of the LDA+U method is to correct the problem that the standard density functional theory (DFT) does not handle the exchange-correlation of strongly correlated electrons perfectly. This problem may lead to the underestimated energy of electron orbits, affecting the electronic structure and energy band calculation results of the material. The LDA+U method corrects this problem by introducing the Hubbard-U correction term. The U parameter is used to describe the local interaction between electrons, and the Coulomb repulsion between electrons can be additionally considered. This method can more accurately describe material systems with strongly correlated electrons, improve the calculation accuracy of key parameters of thermoelectric sensitive materials (such as effective mass, mobility, etc.), provide a reliable basis for subsequent performance optimization, improve the accuracy of calculations, and expand the scope of application of this screening method.

[0025] Furthermore, the cif file output by materials studio is converted into a POSCAR file as the input crystal structure file of VASP through VESTA software. It ensures that the structural model output by Materials Studio can be directly used for subsequent calculations of VASP to solve the compatibility conversion problem. As the file output format of Materials Studio, cif file cannot be directly used in VASP calculations and needs to be converted into POSCAR file. VESTA establishes a connection bridge between Materials Studio and VASP, and also has model visualization and preprocessing functions to ensure the complete technical chain of the screening process. It can simultaneously give play to the advantages of Materials Studio in modeling visualization and the advantages of VASP in high-precision crystal structure calculation. Improve the efficiency and accuracy of file conversion and enhance the applicability and versatility of screening methods.

[0026] Furthermore, according to the deformation potential theory, combined with the relaxation time approximation under the Boltzmann transport theory and the effective mass approximation of the DFT band structure theory, the material crystal model is deformed, and the relationship between the band structure, crystal energy and deformation is calculated to obtain the key parameters in the calculation of thermoelectric performance: elastic constant deformation potential energy and effective mass. The relationship between energy and deformation is fitted to a curve and the second derivative is calculated, and then divided by the crystal volume to obtain the elastic constant. The relationship between the energy value at the bottom of the conduction band or the top of the valence band of the energy band and the deformation is fitted, and the first derivative is calculated to obtain the deformation potential energy of the material. The energy data near the bottom of the conduction band or the top of the valence band of the energy band is selected, and the energy data is fitted with a quadratic function, and the second-order derivative is calculated to obtain the effective mass. The core purpose of calculating this performance parameter is to provide high-precision key parameters for thermoelectric performance calculations. These parameters are the basis of the thermoelectric properties of materials (Seebeck coefficient, conductivity, etc.). The deformation potential theory can achieve a high-precision description of the microscopic electronic structure and crystal properties of materials. Compared with the traditional empirical formula method or semi-classical model method, it has the advantages of not relying on experimental empirical data and being simpler and more accurate in calculation. It is also suitable for the calculation of structures such as doped material systems and low-dimensional materials. It has a wider applicability and more accurate prediction results.

[0027] Furthermore, by converting the electronic structure and energy band data into the input files (intrans, struct, energy files) required by the Boltztrap software, the Seebeck coefficient and conductivity of sensitive materials are calculated. Among them, the struct file records the crystal structure data of the material, including atomic positions, lattice parameters, etc., the energy file contains the electronic state density and energy distribution in the energy band structure, and the intrans file sets specific calculation conditions (temperature range, carrier concentration, etc.). The Boltztrap software is based on the Boltzmann transport theory, combined with the electronic structure and energy band data calculated by the first principles, to predict the thermoelectric performance parameters of the material. The purpose of this method is to achieve accurate prediction from microscopic electronic structure to macroscopic thermoelectric performance. Boltztrap is used to connect the microscopic electronic structure data to the Boltzmann transport theory, forming a calculation chain from electronic structure to thermoelectric performance, and finally completing the calculation of the thermoelectric performance of the material. This method has high calculation accuracy and can realize the calculation of macroscopic thermoelectric performance from microscopic electronic data of first-principles calculation. The Boltztrap output file contains a variety of performance data (Seebeck coefficient, conductivity, carrier concentration, chemical potential, etc.), which supports comprehensive analysis of material performance under different conditions and calculation of complex structures such as doped material systems and low-dimensional materials.

[0028] Furthermore, the relationship diagram between the Seebeck coefficient, conductivity, carrier concentration, and temperature of the material was obtained using origin and other drawing software. The data comes from the calculation results of the BoltzTraP software based on the Boltzmann transport theory, which directly reflects the thermoelectric performance of the material. The purpose is to present the relationship between the Seebeck coefficient, conductivity, carrier concentration, and temperature of the material in a graphical form, which can clearly and intuitively show the interaction and change trend between the performance parameters, and help analyze the change law of these parameters under different conditions (such as temperature or carrier concentration), so as to screen out high-performance thermoelectric materials. This method facilitates intuitive understanding of the change law of thermoelectric performance, shows the interaction between parameters, and makes the performance evaluation more comprehensive.

[0029] It can be understood that the beneficial effects of the second to sixth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0030] In summary, by constructing a complete screening process from crystal structure, electronic structure to thermoelectric performance calculation, the method of the present invention can realize the screening of high-performance thermoelectric materials. A complete first-principles calculation method without experimental data is realized, which can provide reference and guidance for the research and development of thermoelectric materials, significantly reduce the workload of experimental research and development, and solve the problems of long experimental cycle and high experimental cost in the current material selection technology. At the same time, the method of the present invention has no specific restrictions on the type of materials, is applicable to a variety of complex material systems, and has good applicability. And the method of the present invention can calculate and analyze a variety of thermoelectric performance parameters, and reveal the factors that affect the thermoelectric performance of materials, and reveal the direction of improvement of thermoelectric performance.

[0031] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 This is the relationship between the Seebeck coefficient of In2O3 and the carrier concentration and temperature; Figure 2 is the relationship between the Seebeck coefficient of IAO and the carrier concentration and temperature; Figure 3 The relationship between the conductivity of In2O3 and the carrier concentration and temperature; Figure 4is the relationship between the conductivity of IAO and the carrier concentration and temperature; FIG5 is a performance test and simulation calculation diagram of the Seebeck coefficient of indium oxide, wherein (a) is a performance test of the Seebeck coefficient of indium oxide, and (b) is a simulation calculation diagram of the Seebeck coefficient of indium oxide; FIG6 is a performance test and simulation calculation diagram of the IAO Seebeck coefficient, wherein (a) is the performance test of the IAO Seebeck coefficient, and (b) is the simulation calculation of the IAO Seebeck coefficient; FIG. 7 is a performance test and simulation calculation diagram of indium oxide conductivity, wherein (a) is a performance test of indium oxide conductivity, and (b) is a simulation calculation of indium oxide conductivity; FIG8 is a performance test and simulation calculation diagram of IAO conductivity, wherein (a) is the IAO conductivity performance test, and (b) is the IAO conductivity simulation calculation; Fig. 9 A schematic diagram of a computer device provided by an embodiment of the present invention; Fig.10 A block diagram of an electronic device provided according to an embodiment of the present invention; Fig.11 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In the description of the present invention, it should be understood that the terms “include” and “comprises” indicate the presence of described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or collections thereof.

[0036] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0037] It should be further understood that the term "and / or" used in the present specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects are in an "or" relationship.

[0038] It should be understood that, although the terms first, second, third, etc. may be used to describe preset ranges, etc. in the embodiments of the present invention, these preset ranges should not be limited to these terms. These terms are only used to distinguish preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0039] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0040] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0041] The present invention provides a first-principle screening method for a thin-film thermocouple sensitive material system, which adopts the steps of material model establishment, model structure optimization, thermoelectric property calculation, etc., and uses materialsstudio, VESTA, VASP, Boltztrap and other software to realize the full simulation process on a computer, without the need for empirical parameters and experimental test data. The simulation results can provide prediction and guidance for subsequent material preparation, achieving the beneficial effects of reducing experimental costs, reducing experimental cycles, and improving material screening accuracy.

[0042] When performing first-principles calculations, one only needs to determine the atoms used and their positions. No other experimental, empirical or semi-empirical parameters are required. Various physical properties of the material can be deduced based on the calculation of the intrinsic properties of the material. It has good portability and scope of application.

[0043] Example 1 See also Fig.11 The present invention provides a first principle screening method for a thin film thermocouple sensitive material system, comprising the following steps: S1. Obtain the crystal structure of the candidate material, obtain the standard crystal model from the materialsproject database, and adjust the model in the materialsstudio software according to the actual material selection requirements; Search for candidate materials through the existing material database. If you want to perform operations such as doping and modification, modify the standard crystal model in the materialsstudio software.

[0044] S2. Convert the model into POSCAR crystal file by VESTA software, use VASP software for structural optimization, perform self-consistent calculation after convergence, and then perform electronic structure calculation to obtain the energy band diagram and energy of the crystal; VESTA converts the cif file output by materialsstudio into a POSCAR file as the input crystal structure file of VASP. The subsequent structure optimization and property calculations are all performed using VASP (Vienna abinitio Simulation Package) software. The PAW (Projected augmented waves) in the projected augmented waves is used to process the electronic wave function. The electronic structure calculation adopts the LDA+U method, where U is the Hubbard-U correction. The parameters are adjusted in the INCAR file, the plane wave cutoff energy is set to 1.3 times the maximum cutoff energy in the pseudopotential file, and the energy convergence criterion is 10 -5 eV, the K-point density is set to The above guarantees sufficient calculation accuracy.

[0045] S3. Calculate the thermoelectric properties of the material, process the obtained electronic structure and energy band data, obtain the effective mass, deformation potential, elastic constant and other key parameters of the sensitive material based on the deformation potential theory, and calculate the carrier mobility of the material accordingly; The calculation of carrier mobility is based on the deformation potential theory. According to the deformation potential theory, the calculation formula of carrier mobility is as follows:

[0046] in, is the reduced Planck constant, is the elastic constant of the crystal in the α direction, e is the electron charge, is the Boltzmann constant, T is the temperature, is the deformation potential energy of the crystal in the α direction, is the effective mass.

[0047] The elastic constant, deformation potential energy and effective mass are obtained through the relationship between the material's energy band and the crystal deformation. After applying 1%, 0.5%, -1% and -0.5% deformations in a fixed direction of the crystal model, the crystal structure optimization and electronic structure calculation are performed again to obtain the energy and energy band diagram.

[0048] In the calculation of elastic constants, the relationship between energy and deformation is fitted with a curve, the second derivative is calculated, and then divided by the crystal volume to obtain the elastic constant.

[0049] In the deformation potential energy calculation, the relationship between the energy value at the bottom of the conduction band or the top of the valence band and the deformation is fitted, and the first derivative is calculated to obtain the deformation potential energy of the material. Here, the choice of conduction band and valence band is determined according to the semiconductor properties of the material. For n-type semiconductors, conduction band fitting is selected, and for p-type semiconductors, valence band fitting is selected.

[0050] In the calculation of effective mass, the energy data near the bottom of the conduction band or the top of the valence band is selected. The selection basis still depends on the properties of the semiconductor material. A quadratic function is fitted to the energy data, and the second-order derivative is calculated to obtain the effective mass.

[0051] S4. Input the obtained electronic structure and energy band data into the boltztrap software for thermoelectric calculation, obtain the Seebeck coefficient and electrical conductivity of the material, and screen out materials with high thermoelectric properties as sensitive materials for thin film thermocouples.

[0052] The calculated electronic structure and energy band data are converted through VASPKIT software to generate intrans, struct, and energy files as input files for the boltztrap software. The temperature range and temperature gradient, calculation accuracy and other parameters to be calculated for the material are set in the intrans file. After executing the boltztrap calculation command, the material property file is obtained, and the output trace file is the material property data result file.

[0053] The trace file contains data such as Seebeck coefficient, conductivity / relaxation time (Sigma / t), carrier concentration, temperature, etc. The relaxation time needs to be calculated to obtain the conductivity data. Based on the deformation potential theory, the relaxation time is calculated as follows:

[0054] in, is the carrier mobility, is the effective mass and e is the mass of the electron.

[0055] After calculating the relaxation time, multiply it by the conductivity / relaxation time (Sigma / t) to get the conductivity of the material. Use Origin and other drawing software to obtain the relationship between the material's Seebeck coefficient, conductivity, carrier concentration, and temperature, so as to comprehensively screen materials with high Seebeck coefficient, high conductivity, and carrier mobility.

[0056] It will be appreciated by those skilled in the art that various aspects of the present invention may be implemented as systems, methods or program products. Therefore, various aspects of the present invention may be specifically implemented in the following forms, namely: complete hardware implementation, complete software implementation (including firmware, microcode, etc.), or a combination of hardware and software implementations, which may be collectively referred to herein as "circuits", "modules" or "platforms".

[0057] Example 2 The present invention provides a first principles screening system for a thin film thermocouple sensitive material system, which can be used to implement the first principles screening method for the above-mentioned thin film thermocouple sensitive material system. Specifically, the first principles screening system for the thin film thermocouple sensitive material system includes a data module, a conversion module, a processing module and a screening module.

[0058] Among them, the data module obtains the crystal structure of the candidate material, obtains the standard crystal model from the database, and adjusts the model according to the actual material selection requirements; The conversion module converts the adjusted model into a POSCAR crystal file, performs self-consistent calculation after structural optimization convergence, and then performs electronic structure calculation to obtain the electronic structure and energy band data of the crystal; The processing module processes the obtained electronic structure and energy band data, obtains the effective mass, deformation potential energy, and elastic constant of the sensitive material based on the deformation potential theory, and calculates the carrier mobility of the material; The screening module performs thermoelectric calculations on the obtained electronic structure, energy band data, and carrier mobility of the material to obtain the Seebeck coefficient and conductivity of the sensitive material, and screens out materials with high thermoelectric properties as sensitive materials for thin-film thermocouples.

[0059] Example 3 The present invention provides a terminal device, which includes a processor and a memory, wherein the memory is used to store a computer program, the computer program includes program instructions, and the processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or other general-purpose processors, graphics processing units (GPU), tensor processing units (TPU), digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is specifically suitable for loading and executing one or more instructions to implement the corresponding method flow or corresponding function; the processor described in the embodiment of the present invention can be used for the operation of the first principle screening method of the thin film thermocouple sensitive material system, including: The crystal structure of the candidate material is obtained, the standard crystal model is obtained from the database, and the model is adjusted according to the actual material selection requirements; the adjusted model is converted into a POSCAR crystal file, and a self-consistent calculation is performed after the structure optimization converges, followed by an electronic structure calculation to obtain the electronic structure and energy band data of the crystal; the obtained electronic structure and energy band data are processed, and the effective mass, deformation potential energy, and elastic constant of the sensitive material are obtained based on the deformation potential theory, and the carrier mobility of the material is calculated; the obtained electronic structure, energy band data, and carrier mobility of the material are subjected to thermoelectric calculation to obtain the Seebeck coefficient and electrical conductivity of the sensitive material, and materials with high thermoelectric properties are screened out as sensitive materials for thin film thermocouples.

[0060] See also Fig. 9 , the terminal device is a computer device. The computer device 60 of this embodiment includes: a processor 61, a memory 62, and a computer program 63 stored in the memory 62 and executable on the processor 61. When the computer program 63 is executed by the processor 61, the first principle screening method of the thin film thermocouple sensitive material system in the embodiment is implemented. To avoid repetition, it is not described here one by one. Alternatively, when the computer program 63 is executed by the processor 61, the functions of each model / unit in the first principle screening system of the thin film thermocouple sensitive material system in the embodiment are implemented. To avoid repetition, it is not described here one by one.

[0061] The computer device 60 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The computer device 60 may include, but is not limited to, a processor 61 and a memory 62. Those skilled in the art will appreciate that Fig. 9 This is only an example of the computer device 60 and does not constitute a limitation of the computer device 60. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the computer device may also include input and output devices, network access devices, buses, etc.

[0062] The processor 61 may be a central processing unit (CPU), or other general-purpose processors, graphics processing units (GPU), tensor processing units (TPU), digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0063] The memory 62 may be an internal storage unit of the computer device 60, such as a hard disk or memory of the computer device 60. The memory 62 may also be an external storage device of the computer device 60, such as a plug-in hard disk, a smart memory card (SmartMediaCard, SMC), a secure digital (SecureDigital, SD) card, a flash card (FlashCard), etc. equipped on the computer device 60.

[0064] Furthermore, the memory 62 may include both an internal storage unit of the computer device 60 and an external storage device. The memory 62 is used to store computer programs and other programs and data required by the computer device. The memory 62 may also be used to temporarily store data that has been output or is to be output.

[0065] See also Fig.10 The terminal device is an electronic device 600, which is in the form of a general-purpose computing device. The components of the electronic device may include, but are not limited to: at least one processing unit 610, at least one storage unit 620, a bus 630 connecting different platform components (including the storage unit 620 and the processing unit 610), a display unit 640, etc.

[0066] The storage unit stores program codes, which can be executed by the processing unit 610, so that the processing unit 610 performs the steps according to various exemplary embodiments of the present invention described in the above method section of this specification. For example, the processing unit 610 can perform the following steps: Fig.11 Follow the steps shown in .

[0067] The storage unit 620 may include a readable medium in the form of a volatile storage unit, such as a random access memory unit (RAM) 6201 and / or a cache memory unit 6202 , and may further include a read-only memory unit (ROM) 6203 .

[0068] The storage unit 620 may also include a program / utility 6204 having a set (at least one) of program modules 6205, such program modules 6205 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0069] Bus 630 may represent one or more of several types of bus structures, including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.

[0070] The electronic device 600 may also communicate with one or more external devices 700 (e.g., keyboards, pointing devices, Bluetooth devices, etc.), may also communicate with one or more devices that enable a user to interact with the electronic device 600, and / or communicate with any device that enables the electronic device 600 to communicate with one or more other computing devices (e.g., routers, modems, etc.). Such communication may be performed via an input / output (I / O) interface 650. Furthermore, the electronic device 600 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 660. The network adapter 660 may communicate with other modules of the electronic device 600 via a bus 630. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 600, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage platforms, etc.

[0071] Example 4 The present invention also provides a storage medium, specifically a computer-readable storage medium (Memory), which is a memory device in a terminal device for storing programs and data. It is understandable that the computer-readable storage medium here can include both built-in storage media in the terminal device and extended storage media supported by the terminal device, and can be any tangible medium containing or storing a program, which can be used by an instruction execution system, device or device or used in combination with it. The computer-readable storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by a processor are also stored in the storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that more specific examples (non-exhaustive list) of the computer-readable storage medium here include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0072] Computer readable storage media also include data signals propagated in baseband or as part of a carrier wave, which carry readable program codes. Such propagated data signals can take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable storage medium can also be any readable medium other than a readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, device, or device. The program code contained on the readable storage medium can be transmitted using any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above.

[0073] Program code for performing the operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., through the Internet using an Internet service provider).

[0074] One or more instructions stored in a computer-readable storage medium may be loaded and executed by a processor to implement the corresponding steps of the first-principles screening method for a thin-film thermocouple sensitive material system in the above embodiment; one or more instructions in the computer-readable storage medium may be loaded and executed by a processor as follows: The crystal structure of the candidate material is obtained, the standard crystal model is obtained from the database, and the model is adjusted according to the actual material selection requirements; the adjusted model is converted into a POSCAR crystal file, and a self-consistent calculation is performed after the structure optimization converges, followed by an electronic structure calculation to obtain the electronic structure and energy band data of the crystal; the obtained electronic structure and energy band data are processed, and the effective mass, deformation potential energy, and elastic constant of the sensitive material are obtained based on the deformation potential theory, and the carrier mobility of the material is calculated; the obtained electronic structure, energy band data, and carrier mobility of the material are subjected to thermoelectric calculation to obtain the Seebeck coefficient and electrical conductivity of the sensitive material, and materials with high thermoelectric properties are screened out as sensitive materials for thin film thermocouples.

[0075] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0076] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention.

[0077] Based on the first principles, the thermoelectric properties of In2O3 and IAO (In2O3 crystal doped with 2% Al2O3) were simulated and calculated to screen which of In2O3 and IAO is the thin-film thermocouple sensitive material with better performance, and to predict the effect of doped aluminum oxide on the performance of In2O3.

[0078] The In2O3 crystal model was obtained from the materialsproject website, imported into the materialsstudio software, and then the doping adjustment was performed. IAO was established according to the doping ratio to obtain the IAO and In2O3 crystal models.

[0079] The model was converted into a POSCAR crystal file using VESTA software, and the structure was optimized using VASP software. Density functional theory DFT combined with projected augmented wave PAW and PBE functional under generalized gradient approximation GGA was used as the exchange correlation potential between electrons for calculation. In order to ensure sufficient calculation accuracy, the HubburdU value was set for each atom, with the HubburdU value of Alp orbital being 2eV, Ind orbital being 3.0eV, and Op orbital being 5.0eV.

[0080] The cutoff energy Encut=520eV is selected, which is 1.3 times the cutoff energy of oxygen atoms. The K-point grid is generated using the Monhkorst-Pack method, and the K-point grid density is selected as 14×14×14. After determining the K-point and Encut, all ions and lattices are relaxed, and the structure is optimized to determine the lattice constant and atomic position. This structure optimization uses the atomic force and the electron step energy difference as the convergence standard. When the atomic force is less than 10 -2 eV / atom, the electron step energy difference is less than 10 -5 When eV, the optimization process ends.

[0081] The calculation results of VASP are converted through the conversion interface of VASPKIT software to generate intrans, struct, and energy files as input files for boltztrap software. The temperature range and temperature gradient, calculation accuracy and other parameters to be calculated for the material are set in the intrans file. After executing the calculation command of boltztrap, the material property file is obtained, and the output trace file is the material property data result file.

[0082] The carrier mobility and relaxation time are calculated based on the deformation potential theory. The elastic constant, deformation potential and effective mass of In2O3 and IAO are calculated in turn. The carrier mobility is calculated according to the following formula.

[0083] The calculated data at room temperature are shown in the following table: Table 1

[0084] Then calculate it with the data in the trace file to obtain the relationship curve between Seebeck coefficient-temperature-carrier concentration and conductivity-temperature-carrier concentration, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 shown.

[0085] See also Figure 1 , Figure 1The calculated relationship between the Seebeck coefficient of indium oxide and temperature and the carrier concentration is shown in the figure. As the carrier concentration increases, the Seebeck coefficient (absolute value) of indium oxide decreases. 16 / cm 3 When the Seebeck coefficient increases first and then decreases with the increase of temperature, the carrier concentration is greater than 10 16 / cm 3 The Seebeck coefficient increases with the increase of temperature. The calculated Seebeck coefficient of indium oxide is in the range of 50-470μV / K.

[0086] See also Figure 2 , Figure 2 The calculated relationship curve of Seebeck coefficient-temperature-carrier concentration of IAO shows that with the increase of carrier concentration, the Seebeck coefficient (absolute value) of IAO increases first and then decreases. The Seebeck coefficient decreases with the increase of temperature. The calculated Seebeck coefficient of IAO is in the range of 400-1900μV / K. The Seebeck coefficient of IAO is higher than that of indium oxide, indicating that doping 2% aluminum oxide in indium oxide can improve the Seebeck coefficient of the material.

[0087] See also Figure 3 , Figure 3 The calculated conductivity-temperature-carrier concentration curve of indium oxide shows that as the carrier concentration increases, the conductivity of indium oxide increases. As the temperature increases, the conductivity first decreases and then increases. The calculated conductivity of indium oxide is in the range of 300~11000S / m.

[0088] See also Figure 4 , Figure 4 The calculated relationship curve between the conductivity, temperature and carrier concentration of the IAO material is shown. As the carrier concentration increases, the conductivity of IAO gradually increases; at the same time, the conductivity also increases significantly with the increase in temperature. The calculation results show that the conductivity range of IAO is 0.01~100000S / m. When the temperature is below 500K, the conductivity is low, but it still shows the conductive properties of the semiconductor; above 500K, the conductivity of IAO is significantly improved, which is not much different from the conductivity of indium oxide.

[0089] The above results show that IAO has good electrical conductivity, especially in high temperature environment, and is a thermoelectric material with application potential.

[0090] The corresponding samples were prepared by magnetron sputtering and the experimental performance was tested, which was compared with the simulation results. The experimental results are shown in the following table: The temperature and carrier concentration values ​​obtained from the performance test are matched to the simulation results, and the simulation calculation data at the corresponding temperature and carrier concentration are obtained and plotted, and the comparison between the performance test results and the simulation calculation is obtained, as shown in Figures 5, 6, 7 and 8. It can be seen from the figure that the results of the performance test correspond well to the results of the simulation calculation. The change trend of the simulated Seebeck coefficient and conductivity is exactly the same as the test results, among which the simulation and test of the Seebeck coefficient of indium oxide have a good numerical match, and the simulation and test of the conductivity of IAO have a good numerical match. It can be shown that the simulation calculation has good accuracy.

[0091] The results of first-principles calculations show that the Seebeck coefficient of IAO is significantly higher than that of In2O3, while the conductivity is somewhat lower. The doping of surface aluminum oxide will increase the Seebeck coefficient of In2O3 and reduce the conductivity. The conductivity of IAO remains within the range of semiconductors. In the pursuit of a higher Seebeck coefficient (i.e., thermocouple sensitivity), IAO sensitive materials are superior to In2O3.

[0092] In summary, the first principles screening method and system of a thin film thermocouple sensitive material system of the present invention, based on first principles calculations, performs structural relaxation, electronic structure calculations, ductility judgment, and obtains the carrier mobility, Seebeck coefficient, and electrical conductivity of the material through software automation calculations. It has the advantages of fast speed and accurate calculation results, provides theoretical guidance for the screening of thin film thermocouple sensitive materials, and can accurately identify the performance of the material by relying on a computer without experiments, thereby improving the speed of material selection at this stage and reducing experimental costs.

[0093] The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0094] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0095] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in the present invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0096] In the embodiments provided by the present invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0097] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0098] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0099] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0100] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices, and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0101] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0102] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0103] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A first principles screening method for a thin film thermocouple sensitive material system, characterized in that: The following steps are involved: Obtain the crystal structure of the candidate material, obtain the standard crystal model from the database, and adjust the model according to the actual material selection requirements; The adjusted model is converted into a POSCAR crystal file, and a self-consistent calculation is performed after the structure optimization converges, followed by an electronic structure calculation to obtain the electronic structure and energy band data of the crystal; The obtained electronic structure and energy band data are processed, and the effective mass, deformation potential energy, and elastic constant of the sensitive material are obtained based on the deformation potential theory, and the carrier mobility of the material is calculated; The obtained electronic structure, energy band data, and carrier mobility of the material are used for thermoelectric calculations to obtain the Seebeck coefficient and conductivity of the sensitive material, and materials with high thermoelectric properties are screened out as sensitive materials for thin film thermocouples.

2. The first principles screening method for thin film thermocouple sensitive material system according to claim 1, characterized in that: The electronic structure calculation adopts the LDA+U method, where U is the Hubbard-U correction. The parameters are adjusted in the INCAR file, the plane wave cutoff energy is set to 1.3 times the maximum cutoff energy in the pseudopotential file, and the energy convergence criterion is 10 -5 eV, the K-point density is set to above.

3. The first principles screening method for thin film thermocouple sensitive material system according to claim 2, characterized in that: The cif file output by materialsstudio is converted into a POSCAR file through VESTA software as the input crystal structure file of VASP. The subsequent structure optimization and property calculation are all carried out using VASP software, and the PAW in the projected suffix wave is used to process the electronic wave function.

4. The first principles screening method for thin film thermocouple sensitive material system according to claim 1, characterized in that: Carrier mobility of materials for: in, is the reduced Planck constant, is the elastic constant of the crystal in the α direction, e is the electron charge, is the Boltzmann constant, T is the temperature, is the deformation potential energy of the crystal in the α direction, is the effective mass.

5. The first principles screening method for thin film thermocouple sensitive material system according to claim 1, characterized in that: The elastic constant, deformation potential energy and effective mass are obtained through the relationship between the material's energy band and the crystal deformation. After applying 1%, 0.5%, -1% and -0.5% deformations in a fixed direction of the crystal model, the crystal structure optimization and electronic structure calculation are performed again to obtain the energy and energy band diagram.

6. The first principles screening method for thin film thermocouple sensitive material system according to claim 5, characterized in that: Select the energy data of the bottom of the conduction band or the top of the valence band, the selection basis depends on the properties of the semiconductor material; fit the energy data with a quadratic function, and calculate the second-order derivative to obtain the effective mass; In the deformation potential energy calculation, the relationship between the energy value at the bottom of the conduction band or the top of the valence band and the deformation is fitted, and the first derivative is calculated to obtain the deformation potential energy of the material. The selection of the conduction band and the valence band is determined according to the semiconductor properties of the material. For n-type semiconductors, the conduction band is selected for fitting, and for p-type semiconductors, the valence band is selected for fitting. In the calculation of elastic constants, the relationship between energy and deformation is fitted with a curve, the second derivative is calculated, and then divided by the crystal volume to obtain the elastic constant.

7. The first principles screening method for thin film thermocouple sensitive material system according to claim 1, characterized in that: The Seebeck coefficient and conductivity of the sensitive material are obtained as follows: After converting the electronic structure and energy band data, the intrans, struct, and energy files are generated as input files. The temperature range, temperature gradient, and calculation accuracy parameters of the material to be calculated are set in the intrans file. After executing the calculation command, the material property file is obtained, and the output trace file is used as the material property data result file; The obtained trace file contains Seebeck coefficient, conductivity / relaxation time, carrier concentration, and temperature data. The conductivity data is obtained by calculating the relaxation time.

8. The first principles screening method for thin film thermocouple sensitive material system according to claim 7, characterized in that: Calculate relaxation time based on deformation potential theory as follows: in, is the carrier mobility, is the effective mass and e is the mass of the electron.

9. The first principles screening method for thin film thermocouple sensitive material system according to claim 7, characterized in that: The relaxation time is calculated and then multiplied by conductivity / relaxation time to obtain the conductivity of the material. A graphing software is used to obtain a relationship diagram between the material's Seebeck coefficient, conductivity, carrier concentration, and temperature, and materials with high Seebeck coefficient, high conductivity, and carrier mobility are comprehensively screened.

10. A first principles screening system for thin film thermocouple sensitive material system, characterized in that: include: The data module obtains the crystal structure of the candidate material, obtains the standard crystal model from the database, and adjusts the model according to the actual material selection requirements; The conversion module converts the adjusted model into a POSCAR crystal file, performs self-consistent calculation after structural optimization convergence, and then performs electronic structure calculation to obtain the electronic structure and energy band data of the crystal; The processing module processes the obtained electronic structure and energy band data, obtains the effective mass, deformation potential energy, and elastic constant of the sensitive material based on the deformation potential theory, and calculates the carrier mobility of the material; The screening module performs thermoelectric calculations on the obtained electronic structure, energy band data, and carrier mobility of the material to obtain the Seebeck coefficient and conductivity of the sensitive material, and screens out materials with high thermoelectric properties as sensitive materials for thin-film thermocouples.

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