Method of predicting semiconductor carrier mobility

Abstract

The application discloses a method for predicting the carrier mobility of a semiconductor, which comprises the following steps: modeling a target crystal, calculating the carrier mobility, modeling the structural distortion of the target crystal, calculating a correction value, and correcting the carrier mobility calculation result by using the correction value.

Description

Technical Field

[0001] This invention belongs to the field of semiconductors, specifically relating to a method for predicting semiconductor carrier mobility and a method for screening semiconductor materials. Background Technology

[0002] Semiconductors are materials whose conductivity at room temperature falls between that of conductors and insulators. Specifically, they are materials whose conductivity is controllable, ranging from that of insulators to conductors. Optoelectronic materials are materials used to manufacture various optoelectronic devices, such as active and passive optoelectronic sensors, optical information processing and storage devices, and optical communication devices; infrared materials, laser materials, fiber optic materials, and nonlinear optical materials, etc. The carrier mobility of semiconductors and optoelectronic materials directly affects the performance of electronic devices; generally, devices with high carrier mobility are desired. Based on first-principles calculations, the carrier mobility of semiconductors and optoelectronic materials can be calculated, allowing for the prediction of the properties of optoelectronic materials. Materials can then be selected and optoelectronic devices designed based on the desired properties.

[0003] Carrier mobility typically refers to the overall speed of electron and hole movement within a semiconductor, and is a crucial physical quantity for evaluating semiconductor device performance. Mobility affects two main semiconductor properties: First, along with carrier concentration, it determines the conductivity (the reciprocal of resistivity) of the semiconductor material. Higher mobility results in lower resistivity, leading to lower power consumption and greater current carrying capacity for the same current. Second, it influences the device's operating frequency. The most significant limitation to the frequency response characteristics of a bipolar transistor (BPT) is the transit time of minority carriers in the base region. Higher mobility requires a shorter transit time. The transistor's cutoff frequency is directly proportional to the carrier mobility of the base material; therefore, increasing carrier mobility reduces power consumption, increases the device's current carrying capacity, and simultaneously improves the transistor's switching speed.

[0004] Currently, carrier mobility in semiconductors and optoelectronic materials can be experimentally measured, and it can also be calculated and predicted using Boltzmann transport theory and deformation potential theory. However, the carrier mobility predicted by these theories tends to be higher than that measured experimentally. Therefore, researchers are dedicated to finding a method for predicting carrier mobility that yields more accurate results that better reflect reality. The hope is that more precise performance predictions will lead to the discovery of more suitable materials and the design of more sophisticated electronic devices. Summary of the Invention

[0005] In view of this, the present invention provides a method for predicting semiconductor carrier mobility and a method for screening semiconductor materials. These solutions address the problems that carrier mobility prediction is often unrealistic and inaccurate, and that materials screened through prediction do not meet expectations.

[0006] To achieve the above objectives, according to an embodiment of the present invention, the present invention provides a method for predicting the carrier mobility of a semiconductor, which involves modeling a target crystal and calculating the carrier mobility. The method is characterized in that the modeling includes structural distortion of the target crystal and calculation of a correction value, and the carrier mobility calculation result is corrected using the correction value.

[0007] Optionally, the method includes the following steps:

[0008] Obtain the target crystal structure data file; calculate the carrier mobility influence parameters of the target crystal based on the target crystal structure data file; perform structural distortion on the target crystal and calculate the correction value; obtain the carrier mobility of the target crystal based on the carrier mobility influence parameters and the correction value.

[0009] Optionally, the target crystal is structurally distorted, and correction values ​​are calculated, including:

[0010] Construct the unit cell crystal file of the target crystal, and then perform structural distortion on the unit cell crystal file to obtain a distorted unit cell crystal file;

[0011] The band gaps of the primitive cell crystal file and the twisted primitive cell crystal file are calculated separately to obtain the primitive cell band gap and the supercell band gap, respectively.

[0012] Calculate the effective mass correction value based on the primitive cell band gap and the supercell band gap.

[0013] Optionally, a unit cell crystal file of the target crystal is constructed, and the unit cell crystal file is structurally distorted to obtain a distorted unit cell crystal file, including: constructing a unit cell crystal file of the target crystal; performing cell expansion processing on the unit cell crystal file; applying random displacements greater than zero and less than or equal to 0.3 Å to some or all atoms to distort the lattice to obtain a distorted unit cell crystal file.

[0014] Optionally, the effective mass correction value is calculated based on the primitive cell band gap and the supercell band gap, including:

[0015] Based on the primitive band gap and the supercell band gap, the effective mass of the primitive band edge and the effective mass of the supercell band edge are calculated using the effective mass kp perturbation theory. Based on the effective mass of the primitive band edge and the effective mass of the supercell band edge, the effective mass correction value is obtained.

[0016] Optionally, based on the primitive cell band gap and the supercell band gap, the effective mass of the primitive cell band edge and the effective mass of the supercell band edge are calculated using the effective mass kp perturbation theory, respectively. The formula for calculating the effective mass of the band edge is:

[0017]

[0018] in, It is a state with edges | The effective mass, where 0 represents the wave vector at the edge of the band. It is the mass of the free electron. It is a band gap, | These are other eigenstates at position 0.

[0019] Optionally, the target crystal is structurally distorted, and correction values ​​are calculated, including:

[0020] The unit cell crystal of the target crystal is structurally distorted to obtain a distorted unit cell crystal; the structural relaxation, self-consistency calculation and density of states calculation of the distorted unit cell crystal are performed; the unit cell crystal and the distorted unit cell crystal are compared and the correction value is calculated.

[0021] Among these methods, VASP software was used to perform structural relaxation on the twisted unit cell crystal. The relaxation employed a PBE (Perdew-Burke-Ernzerhof) exchange-correlation functional, with energy and force convergence criteria of 1. -6 eV and 5 -3 eV / Å, cutoff energy set to 600 eV; relax the CONTCAR as the POSCAR for static and density of states calculations; and make the k-point density in the KPOINTS file the same as the k-point density in the unit cell crystal.

[0022] Optionally, based on the crystal structure data file, the parameters affecting the carrier mobility of the crystal are calculated, including: structural optimization of the crystal structure data file; and calculation of the effective mass, elastic constant, and deformation potential of the crystal.

[0023] Optionally, the target crystal carrier mobility is obtained based on the carrier mobility influence parameters and correction values, including:

[0024] Substituting the effective mass, elastic constant, and deformation potential into the following formula and multiplying by the correction value yields the carrier mobility of the target crystal. ;

[0025]

[0026] Where e is the electron charge, and k B It is the Boltzmann constant, and T is the temperature. It is the reduced Planck constant; It is the effective mass of the distortion correction, D1 is the deformation potential, and C is the effective mass of the distortion correction. ii It is the elastic constant.

[0027] Alternatively, the effective mass of the crystal can be calculated using the following formula:

[0028]

[0029] in It is the reduced Planck constant. Where is the effective mass of electrons or holes, k is the wave vector, and the band values ​​of E(k) are calculated from the crystal structure data file using the PBE (Perdew-Burke-Ernzerhof) exchange-correlation functional; and the convergence criteria for energy and force are set to 1×10⁻⁶. -6 eV and 1×10 -2 eV / Å, cutoff energy set to 600eV.

[0030] To achieve the above objectives, according to an embodiment of the present invention, the present invention also provides a method for screening semiconductor materials, wherein the semiconductor carrier mobility is predicted by the method described above, and the materials are screened based on the semiconductor carrier mobility.

[0031] The beneficial effects of this invention are:

[0032] The inventors discovered that existing calculation methods lead to predicted values ​​that are higher than actual values ​​because crystals in reality undergo distortion. This local distortion disrupts the spatial symmetry of the original crystal, resulting in an increase in the band gap. Existing calculation methods do not account for this. Therefore, the inventors distorted the crystal structure, calculated correction values, and simulated a more realistic situation. Then, based on the carrier mobility influence parameter and correction values, they obtained the carrier mobility of the target crystal. Because the correction for lattice distortion takes into account changes in carrier mobility, the calculated predictions are more accurate and closer to reality. Attached Figure Description

[0033] Figure 1 E of CsPbCl3 perovskite materials vbm -E 1s Graph showing the relationship between stress and stress;

[0034] Figure 2 E of CsPbCl3 perovskite materials cbm -E 1s Graph showing the relationship between stress and stress;

[0035] Figure 3 Comparison of the calculated density of states of the 2x2x2 twisted supercell and primitive cell of CsPbCl3;

[0036] Figure 4 Flowchart for predicting carrier mobility in CsPbCl3 crystal. Detailed Implementation

[0037] The illustrated embodiments are provided to better illustrate the present invention, but are not intended to limit the scope of the invention to the illustrated embodiments. Therefore, non-essential improvements and adjustments made to the embodiments by those skilled in the art based on the above description of the invention still fall within the protection scope of the present invention.

[0038] The present application will now be described in detail with reference to the accompanying drawings, enabling those skilled in the art to readily implement the invention. However, the invention can be implemented in many different ways, and is not limited to the exemplary embodiments described herein.

[0039] The objectives and advantages of the exemplary embodiments of the present invention will become clearer and more apparent from the description below, but the objectives and advantages of the exemplary embodiments of the present invention are not limited to the following description. In the description of the exemplary embodiments, detailed explanations of the prior art will be omitted where it is believed that such detailed explanations might unnecessarily obscure the focus of the present invention.

[0040] Example 1

[0041] Basic principle explanation:

[0042] This example primarily uses the deformation potential theory to calculate carrier mobility. The deformation potential theory is based on the scattering of electrons and phonons. It posits that lattice vibrations cause changes in the crystal's potential, and these changes cause carriers to scatter in different states, thus determining carrier mobility. Finally, the calculation can be simplified to the following formula:

[0043]

[0044] Where e is the electron charge, and k B It is the Boltzmann constant, and T is the temperature. This is the reduced Planck constant. As can be seen from the formula above, besides some constants, calculating the carrier mobility requires calculating the effective mass of the material separately. Deformation potential D1 and elastic constant C ii Three physical quantities. Using first principles, these three physical quantities, as well as carrier mobility, can be calculated from the crystal structure and band structure of a semiconductor.

[0045] In this regard, we can usually calculate the effective mass through the band structure of the crystal. Band structure refers to the interaction of atomic orbitals when atoms form molecules or even three-dimensional structures, resulting in orbitals with isolated energy levels. The band structure of three-dimensional materials and the method of choosing the k-point along the high symmetry line direction in the Brillouin zone are discussed in detail in the article (Computational Materials Science 128 (2017) 140-184).

[0046] Once the band structure of a crystal is known, the effective mass of its electrons and holes can be calculated using the following formula:

[0047]

[0048] in It is the reduced Planck constant. E(k) is the effective mass of an electron or hole, E(k) is the calculated band structure, and k is the wave vector.

[0049] However, in reality, crystals can become distorted. This local distortion disrupts the spatial symmetry of the original crystal, altering the band structure. Specifically, this leads to an increase in the band gap (a band gap is the distance between adjacent energy bands, allowing them to connect, overlap, or separate; a band gap occurs when energy bands separate). An increase in the band gap increases the effective mass of the band edges. Therefore, the inventors calculated a correction value for the effective mass by simulating crystal distortion, and then used the corrected effective mass... Deformation potential D1 and elastic constant C ii The three physical quantities are used to calculate the carrier mobility using the formula above. Alternatively, the overall correction value for carrier mobility can be calculated directly from the correction value of the effective mass, and then the carrier mobility can be corrected.

[0050] These related calculations can be performed manually, using processors, computers, and other methods, and can also be aided by various software and programs. For example, VASP, short for Vienna Ab-initio Simulation Package, is one of the most popular software programs for materials simulation and computational materials science research. It can handle atoms, molecules, clusters, nanowires (or tubes), thin films, crystals, quasicrystalline and amorphous materials, as well as surface systems and solids, calculating the structural parameters and configurations of materials, calculating the equations of state and mechanical properties (bulk elastic modulus and elastic constants) of materials, calculating the electronic structure (energy levels, charge density distribution, energy bands, electronic density of states) of materials, and calculating the optical properties, magnetic properties, lattice dynamics properties, and molecular dynamics simulations of materials.

[0051] Specifically, such as Figure 4As shown, this paper takes the perovskite optoelectronic material CsPbCl3 of space group 221 (Pm-3m) as an example to explain in detail the prediction and calculation process of carrier mobility, especially the correction of acoustic phonon scattering.

[0052] Step S1: Obtain the CsPbCl3 crystal structure file using the Materials Project crystal database, and convert the structure data file into a .vasp file using VESTA software.

[0053] Step S2: Set up the VASP structure calculation parameter files, including the calculation function setting file (INCAR), crystal system coordinate file (POSCAR), pseudopotential file (POTCAR), and reciprocal lattice vector space description file (KPOINTS).

[0054] Step S3: Based on the parameters set in Step S2, the obtained CsPbCl3 crystal structure is optimized, self-consistently calculated, and its band structure is calculated using VASP software. The more efficient Perdew-Burke-Ernzerhof (PBE) exchange-correlated functional is used in the calculation, and spin-orbit coupling (SOC) is not considered. Furthermore, we set the energy and force convergence criteria to be 1... -6 eV and 1 -2 eV / Å, cutoff energy set to 600 eV.

[0055] After calculating the band structure of space group 221 CsPbCl3, the effective mass of its electrons and holes can be calculated using the following formula:

[0056]

[0057] in It is the reduced Planck constant. E(k) is the effective mass of electrons or holes, E(k) is the calculated band structure, and k is the wave vector. We are studying the mobility along the crystal orientation of CsPbCl3

[100] . The valence band top and conduction band bottom of CsPbCl3 are both located at the highly symmetric R (0.5, 0.5, 0.5) point in the Brillouin zone. Therefore, we need to select the highly symmetric line RM (0.5, 0.5, 0) in the Brillouin zone to calculate its mobility.

[0058] Step S4: The elastic constants of the structure-optimized CsPbCl3 crystal were calculated using VASP software. The calculation employed a PBE exchange-correlated functional and did not consider spin-orbit coupling (SOC). Furthermore, the convergence criteria for energy and force were set to 1. -6 eV and 1 -3 eV / Å, cutoff energy set to 600 eV.

[0059] When calculating the elastic constants of CsPbCl3 crystal, it is important to note that CsPbCl3 in space group 221 belongs to the cubic phase and has three independent elastic constants, namely: C 11 C 12 and C 44 They can be calculated by setting IBRION=6 in INCAR, and the mobility along the

[100] crystal direction is: C ii =C 11 .

[0060] Step S5: The deformation potential of the structure-optimized CsPbCl3 crystal was calculated using VASP software. The PBE exchange-correlated functional was used in the calculation, and spin-orbit coupling (SOC) was not considered. Furthermore, the convergence criteria for energy and force were set to 1. -6 eV and 1 -2 eV / Å, cutoff energy set to 600 eV.

[0061] When calculating the deformation potential of CsPbCl3 crystal, it is necessary to apply a lattice constant along the x-direction. Strains of 0.01, -0.005, 0, 0.005, and 0.01 are plotted, and then the energies E at the conduction band bottom (CBM) and valence band top (VBM) are drawn. cbm and E vbm The relationship between stress and stress is shown in the graph. Figure 1 As shown, the fitted slope yields the corresponding deformation potential, where a0 is the lattice constant of the unstrained CsPbCl3 crystal. When discussing the energy shifts of CBM and VBM under stress, we choose the 1s level E1s of halogens as the reference energy, and then discuss E... cbm -E 1s and E vbm -E 1s The relationship between stress and stress is shown below. Figure 1 and Figure 2 .in Figure 1 E for CsPbCl3 perovskite materials cbm -E 1s Graph showing the relationship between strain and strain. Figure 2 E for CsPbCl3 perovskite materials vbm -E 1s The relationship between strain and deformation potentials. Through fitting, the deformation potentials at the conduction band bottom and valence band top are obtained as follows: D 1c =7.37 eV and D 1v=5.44 eV.

[0062] Step S6: A 2x2x2 CsPbCl3 supercell was constructed using VASPKIT software, and its structure was then distorted. During construction, cell expansion was performed first, resulting in a 2x2x2 CsPbCl3 supercell with 40 atoms. A small displacement of 0.25 Å was then applied to each atom to distort the lattice, thus disrupting the original symmetry of space group 221. This small displacement was random (with inconsistent directions), and displacements of 0.3 Å or less were used to achieve crystal distortion without breaking the chemical bonds within the crystal itself, thus maintaining the crystal structure while simulating crystal distortion.

[0063] Step S7: Perform structural relaxation, self-consistency calculation, and density of states calculation on the constructed twisted 2x2x2 CsPbCl3 supercell. Spin-orbit coupling is not considered during the calculation. The VASP software is used to first perform structural relaxation on the twisted 2x2x2 CsPbCl3 supercell. The more computationally efficient PBE exchange-correlation functional is used during relaxation, with energy and force convergence criteria of 1. -6 eV and 5 -3 eV / Å, cutoff energy set to 600 eV. The relaxed CONTCAR is used as the POSCAR for static calculations and density of states calculations. When performing density of states calculations using VASP, the density at k points in the KPOINTS file should be the same as the density calculated in the unit cell to be compared with the results.

[0064] Step S8: By comparing the band gap calculated using a twisted 2x2x2 CsPbCl3 supercell with the band gap calculated using a CsPbCl3 unit cell, the increase in the effective mass of the twisted CsPbCl3 material is obtained, and further verified by the aforementioned carrier mobility. The calculation formula is corrected to take into account the migration rate of CsPbCl3 perovskite material after distortion.

[0065] Specifically, the bandgap size after distortion is obtained by calculating the density of states using the supercell and compared with the bandgap size calculated using the primitive cell, yielding the result of enhanced bandgap in CsPbCl3 after lattice distortion. According to the effective mass kp perturbation theory, the effective mass of the band edge in a semiconductor material can be expressed as:

[0066]

[0067] in It is a semiconductor band-edge state | The effective mass, where 0 represents the momentum at the edge of the band. It is the mass of the free electron. It is the semiconductor band gap, | These are the other eigenstates at position 0. From the expression above, it can be seen that the semiconductor bandgap... The increase will increase the effective mass of the band edge. The increase in [the effective mass] is therefore the basis for our correction. Our calculations show that the band gap of the twisted CsPbCl3 supercell is larger than that of the CsPbCl3 primitive cell, as follows: Figure 3 As shown, Figure 3 (The left arrow in the figure indicates the supercell, and the right arrow indicates the primitive cell): Comparison of the density of states (DOS) of CsPbCl3 material calculated using a 2x2x2 twisted supercell and a primitive cell. As can be seen from the figure, the band gap calculated using the twisted supercell is larger than that calculated using the primitive cell, increasing from approximately 2.19 eV to 2.55 eV. Therefore, the corrected band gap increases by approximately 1.164 times, and correspondingly, the effective mass also increases by 1.164 times (this is the effective mass correction value). The corrected mobility decreases to 1 / 1.1645 / 2 = 0.684 (this value is the overall correction factor). This means that the effective mass can be calculated and then substituted into the carrier mobility calculation formula, or the mobility can be calculated first and then multiplied by the overall correction factor.

[0068] It is worth noting that the steps numbered S1-S8 do not indicate the execution order of the present invention. They can be performed simultaneously or in different orders as long as the effect of the invention is not affected. In addition, the specific embodiments mentioned above can all be implemented in ways that can be replaced by those skilled in the art without creative effort. Furthermore, these embodiments can be combined or combined with each other to form steps that can achieve the purpose of the present invention, and these steps should also be within the protection scope of the present invention.

[0069] Example 2

[0070] This embodiment uses the calculation of electrical conductivity as an example to illustrate how various performance parameters of a semiconductor can be further calculated and predicted using the predicted carrier mobility.

[0071] After obtaining the carrier mobility through the above steps, various performance parameters of the semiconductor can be calculated using formulas.

[0072] For example, the formula for calculating hole conductivity is:

[0073]

[0074] in, denoted as hole carrier mobility; p is hole concentration; and e is electron charge.

[0075] For n-type semiconductors:

[0076]

[0077] in, Let be the carrier mobility; n be the electron concentration; and e be the electron charge. When two types of carriers conduct electricity simultaneously in a semiconductor, the conductivity is the sum of their values.

[0078] Example 3

[0079] This embodiment takes semiconductor material screening as an example. Based on the parameter range required by electronic devices for semiconductor materials, such as the minimum carrier mobility requirement to achieve a certain function, and based on the crystal structure model data provided by crystal data such as Materials Project, the properties such as carrier mobility, conductivity, and working efficiency are obtained through the above prediction. Potentially suitable materials are screened out, and finally electronic components are manufactured.

[0080] For example, in bipolar transistors, high carrier mobility can shorten the carrier transit time through the base region, thus increasing the characteristic frequency (f). T Improving carrier mobility can significantly enhance the performance of devices, including frequency, speed, and noise. Therefore, for bipolar transistors, it is necessary to select semiconductor materials with high carrier mobility.

[0081] For field-effect transistors (FETs), enhancing the carrier mobility μ in the channel has the same effect as shortening the channel length L, improving the device's driving capability and thus increasing its operating speed. Therefore, for FETs, it is necessary to select semiconductor materials with high carrier mobility.

[0082] For increasing the speed of large-scale integrated circuits, the delay time τ of signal transmission in the integrated circuit is crucial. d It is the logic voltage swing V of the signal m The voltage swing is inversely proportional to the carrier mobility μ. To ensure stable operation of the integrated circuit and prevent it from being affected by heat generation, the logic voltage swing should be appropriately reduced; however, to ensure that the integrated circuit has a high operating speed, the carrier mobility must be increased to shorten the signal transmission delay. Therefore, ultra-high-speed field-effect logic integrated circuits must have a high carrier mobility to be realized.

[0083] For CMOS, the fundamental device of ULSI, enhancing carrier mobility, especially hole mobility, is of paramount importance. Since the hole mobility in Si is approximately 2.5 times smaller than that of electrons, this results in… iTwo major problems arise in CMOS technology: First, in designing CMOS, to ensure the consistency of current flowing through PMOSFETs and NMOSFETs, the gate width of the PMOSFET must be increased by 2.5 times, which inevitably leads to an increase in chip area; second, S... i The highest operating frequency and speed of CMOS devices and their circuits will be limited by the performance of PMOSFETs. Therefore, in the development of RF CMOS integrated circuits and ultra-large scale CMOS integrated circuits, semiconductor properties with high hole mobility need to be screened.

[0084] The above does not list all possible applications.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for predicting semiconductor carrier mobility, comprising modeling a target crystal and calculating the carrier mobility, characterized in that, Includes the following steps: Obtain the target crystal structure data file; Based on the target crystal structure data file, calculate the carrier mobility influence parameters of the target crystal; The target crystal is structurally distorted, and correction values ​​are calculated, including: The process involves constructing a unit cell crystal file for the target crystal and then structurally twisting the unit cell crystal file to obtain a twisted unit cell crystal file. This includes: constructing a unit cell crystal file for the target crystal; performing cell expansion processing on the unit cell crystal file; and applying random displacements of greater than zero and less than or equal to 0.3 Å to the atoms to twist the lattice, thereby obtaining a twisted unit cell crystal file. The band gaps of the primitive cell crystal file and the twisted primitive cell crystal file are calculated separately to obtain the primitive cell band gap and the supercell band gap, respectively. Calculate the effective mass correction value based on the primitive cell band gap and the supercell band gap; Based on the carrier mobility influencing parameters and correction values, the target crystal carrier mobility is obtained, including substituting the effective mass, elastic constant, and deformation potential into the following formula to obtain the target crystal carrier mobility. ; Where e is the electron charge, and k B It is the Boltzmann constant, and T is the temperature. It is the reduced Planck constant; It is the effective mass of the distortion correction, D1 is the deformation potential, and C is the effective mass of the distortion correction. ii It is the elastic constant.

2. The method for predicting semiconductor carrier mobility as described in claim 1, characterized in that, Calculate the effective mass correction value based on the primitive cell band gap and the supercell band gap, including: Based on the primitive band gap and the supercell band gap, the effective mass of the primitive band edge and the effective mass of the supercell band edge are calculated respectively using the effective mass kp perturbation theory. The formula for calculating the effective mass of the edge band is as follows: in, It is a state with edges | The effective mass, where 0 represents the wave vector at the edge of the band. It is the mass of the free electron. It is a band gap, | These are other eigenstates at position 0; Based on the effective mass of the original cell band edge and the effective mass of the supercell band edge, the effective mass correction value is obtained.

3. The method for predicting semiconductor carrier mobility as described in any one of claims 1-2, characterized in that, The target crystal is structurally distorted, and correction values ​​are calculated, including: The unit cell crystal of the target crystal is structurally distorted to obtain a distorted unit cell crystal; Relaxation, self-consistency calculation, and density of states calculation for twisted unit cell crystal structures; Compare unit cell crystals with twisted unit cell crystals and calculate correction values; Among these methods, VASP software was used to perform structural relaxation on the twisted unit cell crystal. The relaxation employed a PBE exchange-correlation functional, with energy and force convergence criteria of 1. -6 eV and 5 -3 eV / Å, cutoff energy set to 600 eV; relax the CONTCAR as the POSCAR for static and density of states calculations; and make the k-point density in the KPOINTS file the same as the k-point density in the unit cell crystal.

4. The method for predicting semiconductor carrier mobility as described in claim 1, characterized in that, Based on the target crystal structure data file, calculate the carrier mobility influence parameters of the target crystal, including: The crystal structure data file is then structurally optimized. Calculate the effective mass, elastic constant, and deformation potential of the crystal.

5. The method for predicting semiconductor carrier mobility as described in claim 1, characterized in that, The effective mass of a crystal is calculated using the following formula: in It is the reduced Planck constant. The effective mass of an electron or hole is given by E(k), where k is the wave vector. The band values ​​of E(k) are calculated from the crystal structure data file using a PBE exchange-correlated functional. The convergence criteria for energy and force are set to 1 × 10⁻⁶. -6 eV and 1×10 -2 eV / Å, cutoff energy set to 600 eV.

6. A method for screening semiconductor materials, characterized in that, The prediction is performed using the method for predicting semiconductor carrier mobility as described in any one of claims 1-5, and the carrier mobility is then used for screening.

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