A method and apparatus for designing a metal-semiconductor interface structure and analyzing contact characteristics
By employing high-throughput screening and global structure optimization methods, the problem of constructing metal-semiconductor interface models was solved, enabling a systematic analysis of the contact characteristics between β-Ga2O3 and metals, and providing complete theoretical guidance for the design of power electronic devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- WUHAN UNIV
- Filing Date
- 2026-04-29
- Publication Date
- 2026-07-21
AI Technical Summary
Existing technologies make it difficult to systematically construct metal-semiconductor interface models, especially in the study of the contact characteristics between β-Ga2O3 and metals. It is difficult to construct the interface structure, obtain the globally optimal structure, analyze the contact characteristics in a non-systematic manner, and lack comprehensive evaluation methods.
By employing high-throughput screening and global structure optimization methods, an initial interface model is constructed by acquiring crystal plane data of semiconductors and metals, and global structure optimization is performed. The interface binding energy, charge transfer, Schottky barrier and tunneling probability are calculated, providing a method and apparatus for metal-semiconductor interface structure design and contact characteristic analysis.
The system enables the construction of metal-semiconductor interfaces, automatically searches for the globally optimal structure, and comprehensively evaluates interface characteristics, providing theoretical guidance for the selection of metal materials in device design and improving the accuracy of interface stability and charge transfer characteristic analysis.
Smart Images
Figure CN122433656A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the technical field of metal-semiconductor interface and computer-aided design, specifically relating to a method and apparatus for metal-semiconductor interface structure design and contact characteristic analysis. Background Technology
[0002] Metal-semiconductor interfaces (metal-semiconductor interfaces) are core components of power electronic devices, Schottky diodes, and field-effect transistors. The atomic structure, stability, and electron transport characteristics of the interface directly determine the contact resistance, switching speed, and reliability of the device. Ultra-wide bandgap semiconductors, represented by β-Ga₂O₃, have become candidate materials for next-generation power devices due to their high breakdown field strength and thermal stability. However, research on the contact characteristics of β-Ga₂O₃ with metals still faces the following challenges: Constructing the interface structure is difficult: the lattice constants of the metal and β-Ga2O3 are very different, the lattice mismatch rate is high when constructing the interface model manually, and it is difficult to traverse all possible crystal orientation combinations, resulting in insufficient representativeness of the interface model.
[0003] Globally optimal structure is difficult to obtain: The potential energy surface of the metal-semi interface is complex, and traditional structure optimization methods (such as the conjugate gradient method) are prone to getting trapped in local minima, and cannot guarantee obtaining the globally most stable interface configuration.
[0004] The analysis of contact characteristics is not systematic: existing studies are mostly focused on single metals or single crystal planes, lacking systematic comparative analysis of multiple metals (with different work functions) and multiple β-Ga2O3 crystal planes, especially lacking a unified evaluation method for comprehensive characteristics such as interfacial binding energy, charge transfer, Schottky barrier, and tunneling probability.
[0005] Therefore, there is an urgent need to develop a method that can systematically construct metal-semiconductor interfaces, automatically search for globally optimal structures, and comprehensively analyze contact characteristics, so as to provide theoretical guidance for the selection of metal materials in device design. Summary of the Invention
[0006] To address the aforementioned technical problems, this application provides a method and apparatus for designing metal-semiconductor interface structures and analyzing contact characteristics.
[0007] The method provided in this application is as follows.
[0008] Firstly, a method for designing metal-semiconductor interface structures and analyzing contact characteristics is provided, including: Acquire crystal plane data of semiconductor and metallic materials; The types of exposed atoms and the size of the supercell are detected on the surface. The lattice mismatch rate of all metal-semiconductor combinations is calculated. Candidate crystal plane combinations are obtained through high-throughput screening. Construct an initial interface model corresponding to the candidate crystal plane combination, perform global structure optimization, and obtain the optimal interface configuration; Calculate the binding energy, differential charge density, and total migrated charge of the optimal interface configuration, and evaluate the interface stability and charge transfer characteristics; Calculate the local density of states for the optimal interface configuration to determine the Schottky barrier height and contact type; Calculate the average electrostatic potential distribution of the optimal interface configuration, extract the tunneling barrier height and width, and calculate the tunneling probability. By combining the interface index calculation results of various candidate crystal plane combinations, the contact performance between different metals and semiconductors is evaluated.
[0009] In one possible implementation, the high-throughput screening conditions include: the exposed atoms on the surface contain only one type of atom; the dimensions of the interface supercell in both the x and y directions are smaller than a set threshold; and the lattice mismatch rate is less than a threshold.
[0010] In one possible implementation, constructing the initial interface model corresponding to the candidate crystal plane combination, performing global structure optimization, and obtaining the optimal interface configuration includes: An initial interface model corresponding to the candidate crystal plane combination is constructed using an interface prediction and generation method. An adaptive minimum jump method is used to optimize the global structure of the initial interface model, searching for the global minimum of the interface potential energy surface to obtain the optimal interface configuration.
[0011] In one possible implementation, the bonding energy of the gold semi-interface... E b The formula is: in, , and These represent the total energy after structural relaxation at the metal / semiconductor interface, metal surface, and semiconductor surface, respectively. N This indicates the number of oxygen atoms at the interface; The differential charge density Δ at the gold semi-interface ρ ( z The formula is:
[0012] in, , and These represent the planar average charge density of the stable configurations at the metal / semiconductor interface, metal surface, and semiconductor surface, respectively. The total amount of transferred charge is determined by the three-dimensional distribution and planar average value of the differential charge density to identify the electron accumulation and depletion regions at the interface, and the total amount of charge transferred from the metal to the semiconductor is quantitatively calculated.
[0013] In one possible implementation, calculating the local density of states of the optimal interface configuration, determining the Schottky barrier height and contact type, includes: The local density of states at the gold-semiconductor interface is calculated using hybrid functionals; the Fermi level position, as well as the valence band top and conduction band bottom energies of the semiconductor side far from the interface, are read from the local density of states diagram. The height of the Schottky barrier is: for an n-type Schottky barrier, it is the distance from the Fermi level to the bottom of the conduction band; for a p-type Schottky barrier, it is the distance from the Fermi level to the top of the valence band. The contact type is determined as n-type or p-type based on whether the Fermi level is closer to the bottom of the conduction band or the top of the valence band. Calculate the partial density of states at the gold-semiconductor interface, analyze the existence of metal-induced bandgap states and their decay with the number of semiconductor layers, and evaluate the strength of the Fermi level pinning effect. Plot a scatter plot of the Schottky barrier height as a function of the metal work function, and obtain the pinning factor through linear fitting. S This is to determine whether the interface conforms to the Schottky-Mott rule.
[0014] In one possible implementation, the average electrostatic potential distribution of the optimal interface configuration is calculated, the tunneling barrier height and width are extracted, and the tunneling probability is calculated, including: Calculate the macroscopic average electrostatic potential and planar average electrostatic potential distribution along the z-direction of the gold semi-metal interface; identify the potential barrier region above the Fermi level at the interface, using the Fermi level as a reference. Extracting the tunnel barrier height Δ V and tunnel barrier width W B ; Calculate the tunneling probability from metal to semiconductor T B The formula is:
[0015] in, m The effective mass of electrons in a semiconductor. is the reduced Planck constant.
[0016] Secondly, a device for designing metal-semiconductor interface structures and analyzing contact characteristics is provided, comprising: The acquisition module is used to acquire crystal plane data of semiconductor and metallic materials; The screening module is used to detect the type of exposed atoms and the size of the supercell on the surface, calculate the lattice mismatch rate of all metal-semiconductor combinations, and obtain candidate crystal plane combinations through high-throughput screening. The construction module is used to construct the initial interface model corresponding to the candidate crystal plane combination, perform global structural optimization, and obtain the optimal interface configuration. The first calculation module is used to calculate the binding energy, differential charge density, and total migrated charge of the optimal interface configuration, and to evaluate the interface stability and charge transfer characteristics. The second calculation module is used to calculate the local density of states of the optimal interface configuration and determine the Schottky barrier height and contact type. The third calculation module is used to calculate the average electrostatic potential distribution of the optimal interface configuration, extract the tunneling barrier height and width, and calculate the tunneling probability. The evaluation module is used to synthesize the interface index calculation results of various candidate crystal plane combinations to evaluate the contact performance between different metals and semiconductors.
[0017] Thirdly, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the metal-semiconductor interface structure design and contact characteristic analysis method as described in the first aspect.
[0018] Fourthly, a non-transitory computer-readable storage medium is provided, on which a computer program is stored, wherein when the computer program is executed by a processor, it implements the metal-semiconductor interface structure design and contact characteristic analysis method as described in the first aspect.
[0019] Fifthly, a computer program product is provided, comprising a computer program that, when executed by a processor, implements the metal-semiconductor interface structure design and contact characteristic analysis method as described in the first aspect.
[0020] The present application has the following beneficial effects: The method provided in this application, through high-throughput screening, automatic construction of interface atomic structures, and global optimization design, enables the system to construct metal-semiconductor interfaces and automatically search for the globally optimal structure.
[0021] The method provided in this application enables a unified evaluation of comprehensive properties such as interface binding energy, charge transfer, Schottky barrier, and tunneling probability.
[0022] The method provided in this application can achieve full-chain integration of screening, construction, optimization design and comprehensive evaluation, and provide a complete solution and theoretical guidance for the selection of metal materials in device design. Attached Figure Description
[0023] Figure 1A schematic flowchart illustrating the metal-semiconductor interface structure design and contact characteristic analysis method provided in this application embodiment; Figure 2 Metals provided for embodiments of this application β -Flowchart of Ga2O3 interface structure design; Figure 3 Eight metals / provided for embodiments of this application β -Atomic structure of the Ga2O3 interface; Figure 4 The relationship between the interlayer spacing and (a) the metal work function and (b) the interfacial bonding energy provided for embodiments of this application; Figure 5 Charge accumulation at the gold semiconductor interface provided in the embodiments of this application The relationship between (a) interlayer spacing and (b) metal work function; Figure 6 The eight metals provided in the embodiments of this application β - Distribution diagrams of macroscopic average electrostatic potential and planar average electrostatic potential along the z-direction of the Ga2O3 interface. Figure 7 A structural diagram of the metal-semiconductor interface structure design and contact characteristic analysis device provided in an embodiment of this application; Figure 8 This is a structural diagram of an electronic device provided in an embodiment of this application. Detailed Implementation
[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0025] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0026] In the description of this application, spatial relation terms such as "below," "under," "below," "below," "above," "over," etc., are used herein to describe the relationship between one element or feature shown in the figures and other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figures is flipped, an element or feature described as "below" or "under" or "below" of other elements or features will be oriented "above" other elements or features. Therefore, the exemplary terms "below" and "under" can include both upper and lower orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein are interpreted accordingly.
[0027] In the description of this application, the term "for example" is used to mean "used as an example, illustration, or description." Any embodiment described as "for example" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use this application. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that this application can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid unnecessarily obscuring the description of this application. Therefore, this application is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.
[0028] Currently, existing research on the contact characteristics of semiconductors and metals still faces the following problems: difficulty in constructing interface structures, difficulty in obtaining globally optimal structures, and unsystematic analysis of contact characteristics.
[0029] In view of this, this application provides a method and apparatus for metal-semiconductor interface structure design and contact characteristic analysis.
[0030] See Figure 1 This invention provides a method for designing metal-semiconductor interface structures and analyzing contact characteristics, comprising the following steps: S101. Obtain crystal plane data of semiconductor materials and metal materials.
[0031] In one possible implementation, the semiconductor material has multiple low-index crystal planes, including (001), (100), (1011), etc., and the metal material has close-packed crystal planes, including (100), (111).
[0032] S102. Detect the type of exposed atoms and the supercell size on the surface, calculate the lattice mismatch rate of all metal-semiconductor combinations, and obtain candidate crystal plane combinations through high-throughput screening.
[0033] In one possible implementation, the detection of exposed surface atom types includes detecting exposed atom types on the surfaces of semiconductor and metallic materials. For example, β -Ga2O3 has only Ga atoms or only O atoms exposed on the side.
[0034] In one possible implementation, the high-throughput screening conditions are: the exposed atoms on the surface contain only one type of atom; the size of the interface supercell in both the x and y directions is smaller than a set threshold (preferably 15 Å); and the lattice mismatch rate is less than a threshold.
[0035] Furthermore, the threshold value of the lattice mismatch rate can be set to 5%-10%, preferably 5%.
[0036] It should be noted that in crystallography, when discussing the x and y directions of a unit cell, we are referring to the two basis vector directions of the unit cell, which typically correspond to: x-direction: corresponds to the a-axis (the direction of one edge of the unit cell). y-direction: corresponds to the b-axis (the direction of another edge of the unit cell). Furthermore, these three directions satisfy a right-handed screw relationship, forming a complete coordinate system together with the z-direction (c-axis).
[0037] S103. Construct the initial interface model corresponding to the candidate crystal plane combination, perform global structure optimization, and obtain the optimal interface configuration.
[0038] In one possible implementation, S103 includes: S103a. Construct the initial interface model corresponding to the candidate crystal plane combination; during construction, fix the lattice constant on the semiconductor side, adjust the lattice on the metal side to match the semiconductor, and set the number of metal layers and the number of semiconductor layers. S103b: The initial interface model is structurally optimized using the conjugate gradient method to search for the minimum value of the interface potential energy surface and obtain a stable interface configuration. During the optimization process, a vacuum layer (preferably 20 Å) is added in the z-direction of the interface, and the two bottom atomic layers of the semiconductor are fixed. For the optimized interface, the interface spacing (the average atomic distance between the metal and semiconductor contact layers) is calculated.
[0039] S104. Calculate the binding energy, differential charge density, and total migrated charge of the optimal interface configuration, and evaluate the interface stability and charge transfer characteristics.
[0040] In one possible implementation, the bonding energy of the gold semi-interface... Eb The formula is: in, , and These represent the total energy after structural relaxation at the metal / semiconductor interface, metal surface, and semiconductor surface, respectively. N This indicates the number of oxygen atoms at the interface.
[0041] In one possible implementation, the differential charge density Δ at the gold semi-interface... ρ ( z The formula is:
[0042] in, , and These represent the planar average charge density of the stable configurations at the metal / semiconductor interface, metal surface, and semiconductor surface, respectively.
[0043] In one possible implementation, the total amount of transferred charge is determined by the three-dimensional distribution and planar average of the differential charge density to identify regions of electron accumulation (positive) and depletion (negative) at the interface, and the total amount of charge transferred from the metal to the semiconductor is quantitatively calculated.
[0044] S105. Calculate the local density of states of the optimal interface configuration and determine the Schottky barrier height and contact type.
[0045] In one possible implementation, S105 includes: S105a. Calculate the local density of states at the gold semiconductor interface using hybrid functionals; read the Fermi level position and the valence band top and conduction band bottom energies of the semiconductor side far from the interface from the local density of states diagram; S105b, the Schottky barrier height is: for an n-type Schottky barrier, it is the distance from the Fermi level to the bottom of the conduction band; for a p-type Schottky barrier, it is the distance from the Fermi level to the top of the valence band; the contact type is determined as n-type or p-type depending on whether the Fermi level is closer to the bottom of the conduction band or the top of the valence band. S105c, calculate the partial wave density of states at the gold-semiconductor interface, analyze the existence of metal-induced bandgap states and their decay law with the number of semiconductor layers, and evaluate the strength of the Fermi level pinning effect. S105d. Plot a scatter plot of the Schottky barrier height as a function of the metal work function, and obtain the pinning factor through linear fitting. S This is to determine whether the interface conforms to the Schottky-Mott rule.
[0046] Furthermore, in S105b, if the Fermi level is closer to the bottom of the conduction band, the contact type is n-type; if the Fermi level is closer to the top of the valence band, the contact type is p-type.
[0047] S106. Calculate the average electrostatic potential distribution of the optimal interface configuration, extract the tunneling barrier height and width, and calculate the tunneling probability.
[0048] In one possible implementation, S106 includes: S106a. Calculate the macroscopic average electrostatic potential and planar average electrostatic potential distribution along the z-direction of the gold semi-metal interface; using the Fermi level as a reference, identify the potential barrier region above the Fermi level at the interface. S106b, Extracting the tunnel barrier height Δ V (Maximum height of the barrier region) and width of the tunnel barrier W B (Half-width of the barrier region at the Fermi level); S106c, Calculate the tunneling probability from metal to semiconductor. T B The formula is:
[0049] in, m The effective mass of electrons in a semiconductor. is the reduced Planck constant.
[0050] S107. Based on the calculation results of the interface indices of various candidate crystal plane combinations, evaluate the contact performance between different metals and semiconductors.
[0051] In one possible implementation, in S107, For the bonding energy of the gold semi-interface E b : A value less than 0 indicates a stable metal / semiconductor interface structure; conversely, a value greater than 0 indicates an unstable interface structure. Interface bonding energy. The smaller the value, the stronger the bonding effect at the metal / semiconductor interface, and the more stable the resulting metal-semiconductor interface. Regarding the total amount of transferred charge: The total amount of transferred charge reflects the degree of Fermi level pinning and the amplitude of interface dipole formation. The more electrons a metal loses, the more beneficial it is to lower the n-type barrier or to ohmize the p-type contact.
[0052] Regarding the Schottky barrier height: The Schottky barrier height directly determines the electrical properties. The lower the barrier, the closer the contact is to Ohmic behavior. It, along with the contact type determination, depends on the strength of the Fermi level pinning and the matching of the metal work function.
[0053] For contact types: n-type or p-type; for semiconductors pre-defined as n-type: the calculation focuses on the electron barrier (the difference between the conduction band bottom and the metal Fermi level). If this barrier height is extremely low (close to 0 or negative), the interface is determined to be an ohmic contact; if the barrier is high (typically >0.3 eV), it is a Schottky contact. For semiconductors pre-defined as p-type: the calculation focuses on the hole barrier (the difference between the metal Fermi level and the valence band top). Logically, a low barrier corresponds to an ohmic contact, and a high barrier corresponds to a Schottky contact.
[0054] For metal-to-semiconductor tunneling probability T B The higher the tunneling probability, the easier it is for electrons to pass through the interface, and the lower the contact resistance.
[0055] Based on the above evaluation of contact performance, metals suitable for ohmic contacts (low Schottky barrier, high tunneling probability) and metals suitable for Schottky contacts (high Schottky barrier, low leakage current) were selected, providing a basis for device design.
[0056] The following detailed embodiments illustrate this point.
[0057] In this embodiment, β-Ga2O3 is used as the semiconductor, and eight metals (Sc, Al, Ag, Cu, Co, Pd, Au, and Pt, with work functions ranging from 3.50 eV to 5.65 eV) are selected. The interface is constructed according to the method of this application, and the contact characteristics are analyzed.
[0058] 1. Screening of candidate crystal plane combinations The β-Ga2O3 crystal planes are (001), (100), and (201); the metal crystal planes are (100) or (111) of the FCC structure.
[0059] Calculate the lattice mismatch rate for each combination, and adjust the metal lattice based on the β-Ga₂O₃ lattice. Screening conditions: lattice mismatch rate <10%, interface supercell x and y directions <15 Å, and surface exposure of a single atom type.
[0060] Screening results: The optimal matching crystal planes and mismatch rates for each metal are as follows: Sc(100) / β-Ga2O3(201) 1.65%, Al(100) / β-Ga2O3(001) 2.66%, Ag(100) / β-Ga2O3(100) 0.42%, Cu(111) / β-Ga2O3(201) 2.34%, Co(100) / β-Ga2O3(201) 1.04%, Pd(100) / β-Ga2O3(100) 2.74%, Au(100) / β-Ga2O3(001) 1.58%, Pt(100) / β-Ga2O3(100) 2.29%, as shown in Table 1. All interface lattice mismatch rates are <5%.
[0061] Table 1 Metals and β -Lattice mismatch rate of different crystal planes of Ga2O3 (%)
[0062] 2. Interface Design and Global Optimization The number of metal layers was set to 4, and the number of β-Ga₂O₃ layers was set to 10, followed by global structure optimization. A 20 Å vacuum layer was added to fix the bottom two layers of atoms in the β-Ga₂O₃ layer.
[0063] The optimized metal / gallium oxide interface structure is as follows: Figure 3 As shown in the figure, the Sc, Co, and Cu interfaces have the smallest interfacial spacing and the strongest bonding effect.
[0064] 3. Binding energy and charge transfer The calculated binding energy results are as follows: Sc / β-Ga₂O₃ is -3.81 eV / #O, Co / β-Ga₂O₃ is -2.91 eV / #O, Cu / β-Ga₂O₃ is -2.10 eV / #O, and the rest are all greater than -2.0 eV / #O. Sc has the lowest binding energy and is the most stable. Figure 4 As shown.
[0065] Differential charge density analysis: The cumulative charge Δq at the Sc / β-Ga2O3, Co / β-Ga2O3, and Cu / β-Ga2O3 interfaces are 0.77 e, 0.73 e, and 0.47 e, respectively, significantly higher than other interfaces. Charge transfer occurs from the metal side to the β-Ga2O3 side, mainly accumulating between the metal and oxygen atoms, forming metal-oxygen bonds.
[0066] 4. Schottky Barrier and Contact Types The local density of states was calculated using the HSE06 hybrid functional. The Schottky barrier heights were obtained as follows: Sc / β-Ga₂O₃ 3.12 eV, Al / β-Ga₂O₃ 3.61 eV, Ag / β-Ga₂O₃ 2.97 eV, Cu / β-Ga₂O₃ 0.23 eV, Co / β-Ga₂O₃ 3.23 eV, Pd / β-Ga₂O₃ 2.28 eV, Au / β-Ga₂O₃ 3.00 eV, and Pt / β-Ga₂O₃ 2.81 eV. Figure 5 As shown.
[0067] Contact type determination: Cu / β-Ga2O3 and Pd / β-Ga2O3 are p-type (Fermi level near the top of the valence band), while the rest are n-type (Fermi level near the bottom of the conduction band).
[0068] Partial density of states analysis revealed a significant metal-induced bandgap state in the first layer of β-Ga₂O₃ at the interface, which rapidly decayed with increasing layer number, essentially disappearing by the third layer. The fitting pinning factor of the Schottky barrier as a function of the metal work function was approximately 0.16, close to the theoretical empirical value of 0.11, indicating a strong Fermi pinning effect.
[0069] 5. Tunneling Barrier and Tunneling Probability like Figure 6 As shown, the tunneling barrier height Δ at each interface is extracted based on the average electrostatic potential distribution. V and width W B The tunneling probability was calculated using the formula. Results: The Sc / β-Ga2O3 interface had the highest tunneling probability at 34.82%; the Au / β-Ga2O3 and Pt / β-Ga2O3 interfaces had lower tunneling probabilities, at 11.26% and 17.92%, respectively.
[0070] 6. Comprehensive Assessment The Schottky barrier at the Cu / / β-Ga2O3 interface is only 0.23 eV, and the tunneling probability is moderate, making it suitable as an ohmic contact electrode.
[0071] Schottky barriers at interfaces such as Sc, Al, Ag, Co, Au, and Pt are high (>2.8 eV), making them suitable as Schottky contact electrodes. Among them, Sc has the most stable interface bonding and the highest tunneling probability, which is beneficial for electron injection.
[0072] This embodiment verifies that the method provided in this application can effectively screen and evaluate metal-semiconductor interfaces, providing a theoretical basis for the selection of metal electrodes for β-Ga2O3 devices.
[0073] The apparatus for designing and analyzing the metal-semiconductor interface structure provided in this application is described below. The apparatus for designing and analyzing the metal-semiconductor interface structure described below can be referred to in correspondence with the method for designing and analyzing the metal-semiconductor interface structure described above.
[0074] Figure 7 This is a schematic diagram of the metal-semiconductor interface structure design and contact characteristic analysis device provided in the embodiments of this application, as shown below. Figure 7 As shown, it includes: an acquisition module 71, a filtering module 72, a construction module 73, a first calculation module 74, a second calculation module 75, a third calculation module 76, and an evaluation module 77, wherein: Acquisition module 71 is used to acquire crystal plane data of semiconductor materials and metal materials; The screening module 72 is used to detect the type of exposed atoms and the size of the supercell on the surface, calculate the lattice mismatch rate of all metal-semiconductor combinations, and obtain candidate crystal plane combinations through high-throughput screening. Construction module 73 is used to construct the initial interface model corresponding to the candidate crystal plane combination, perform global structure optimization, and obtain the optimal interface configuration; The first calculation module 74 is used to calculate the binding energy, differential charge density and total migrated charge of the optimal interface configuration, and to evaluate the interface stability and charge transfer characteristics. The second calculation module 75 is used to calculate the local density of states of the optimal interface configuration and determine the Schottky barrier height and contact type. The third calculation module 76 is used to calculate the average electrostatic potential distribution of the optimal interface configuration, extract the tunneling barrier height and width, and calculate the tunneling probability. Evaluation module 77 is used to integrate the interface index calculation results of various candidate crystal plane combinations to evaluate the contact performance between different metals and semiconductors.
[0075] Figure 8 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 8 As shown, the electronic device may include a processor 810, a communications interface 820, a memory 830, and a communications bus 840. The processor 810, communications interface 820, and memory 830 communicate with each other via the communications bus 840. The processor 810 can call logic instructions from the memory 830 to execute methods for metal-semiconductor interface structure design and contact characteristic analysis.
[0076] Furthermore, the logical instructions in the aforementioned memory 830 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0077] On the other hand, this application also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to execute the metal-semiconductor interface structure design and contact characteristic analysis methods provided by the above methods.
[0078] In another aspect, this application also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, is implemented to perform the metal-semiconductor interface structure design and contact characteristic analysis methods provided by the above methods.
[0079] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.
[0080] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.
[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A method for designing metal-semiconductor interface structures and analyzing contact characteristics, characterized in that, include: Acquire crystal plane data of semiconductor and metallic materials; The types of exposed atoms and the size of the supercell are detected on the surface. The lattice mismatch rate of all metal-semiconductor combinations is calculated. Candidate crystal plane combinations are obtained through high-throughput screening. Construct an initial interface model corresponding to the candidate crystal plane combination, perform global structure optimization, and obtain the optimal interface configuration; Calculate the binding energy, differential charge density, and total migrated charge of the optimal interface configuration, and evaluate the interface stability and charge transfer characteristics; Calculate the local density of states for the optimal interface configuration to determine the Schottky barrier height and contact type; Calculate the average electrostatic potential distribution of the optimal interface configuration, extract the tunneling barrier height and width, and calculate the tunneling probability. By combining the interface index calculation results of various candidate crystal plane combinations, the contact performance between different metals and semiconductors is evaluated.
2. The method according to claim 1, characterized in that, The conditions for high-throughput screening include: the exposed atoms on the surface contain only one type of atom; the size of the interface supercell in both the x and y directions is smaller than a set threshold; and the lattice mismatch rate is less than a threshold.
3. The method according to claim 1, characterized in that, The process of constructing the initial interface model corresponding to the candidate crystal plane combination, performing global structure optimization, and obtaining the optimal interface configuration includes: An initial interface model corresponding to the candidate crystal plane combination is constructed using an interface prediction and generation method. An adaptive minimum jump method is used to optimize the global structure of the initial interface model, searching for the global minimum of the interface potential energy surface to obtain the optimal interface configuration.
4. The method according to claim 1, characterized in that, The bonding energy of the gold semi-interface E b The formula is: in, , and These represent the total energy after structural relaxation at the metal / semiconductor interface, metal surface, and semiconductor surface, respectively. N This indicates the number of oxygen atoms at the interface; The differential charge density Δ at the gold semi-interface ρ ( z The formula is: in, , and These represent the planar average charge density of the stable configurations at the metal / semiconductor interface, metal surface, and semiconductor surface, respectively. The total amount of transferred charge is determined by the three-dimensional distribution and planar average value of the differential charge density to identify the electron accumulation and depletion regions at the interface, and the total amount of charge transferred from the metal to the semiconductor is quantitatively calculated.
5. The method according to claim 1, characterized in that, The calculation of the local density of states of the optimal interface configuration, and the determination of the Schottky barrier height and contact type, include: The local density of states at the gold-semiconductor interface is calculated using hybrid functionals; the Fermi level position, as well as the valence band top and conduction band bottom energies of the semiconductor side far from the interface, are read from the local density of states diagram. The height of the Schottky barrier is: for an n-type Schottky barrier, it is the distance from the Fermi level to the bottom of the conduction band; for a p-type Schottky barrier, it is the distance from the Fermi level to the top of the valence band. The contact type is determined as n-type or p-type depending on whether the Fermi level is closer to the bottom of the conduction band or the top of the valence band. Calculate the partial density of states at the gold-semiconductor interface, analyze the existence of metal-induced bandgap states and their decay with the number of semiconductor layers, and evaluate the strength of the Fermi level pinning effect. Plot a scatter plot of the Schottky barrier height as a function of the metal work function, and obtain the pinning factor through linear fitting. S This is to determine whether the interface conforms to the Schottky-Mott rule.
6. The method according to claim 1, characterized in that, Calculate the average electrostatic potential distribution of the optimal interface configuration, extract the tunneling barrier height and width, and calculate the tunneling probability, including: Calculate the macroscopic average electrostatic potential and planar average electrostatic potential distribution along the z-direction of the gold semi-metal interface; identify the potential barrier region above the Fermi level at the interface, using the Fermi level as a reference. Extracting the tunnel barrier height Δ V and tunnel barrier width W B ; Calculate the tunneling probability from metal to semiconductor T B The formula is: in, m The effective mass of electrons in a semiconductor. is the reduced Planck constant.
7. A device for designing metal-semiconductor interface structures and analyzing contact characteristics, characterized in that, include: The acquisition module is used to acquire crystal plane data of semiconductor and metallic materials; The screening module is used to detect the type of exposed atoms and the size of the supercell on the surface, calculate the lattice mismatch rate of all metal-semiconductor combinations, and obtain candidate crystal plane combinations through high-throughput screening. The construction module is used to construct the initial interface model corresponding to the candidate crystal plane combination, perform global structural optimization, and obtain the optimal interface configuration. The first calculation module is used to calculate the binding energy, differential charge density, and total migrated charge of the optimal interface configuration, and to evaluate the interface stability and charge transfer characteristics. The second calculation module is used to calculate the local density of states of the optimal interface configuration and determine the Schottky barrier height and contact type. The third calculation module is used to calculate the average electrostatic potential distribution of the optimal interface configuration, extract the tunneling barrier height and width, and calculate the tunneling probability. The evaluation module is used to synthesize the interface index calculation results of various candidate crystal plane combinations to evaluate the contact performance between different metals and semiconductors.
8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the metal-semiconductor interface structure design and contact characteristic analysis method as described in any one of claims 1 to 6.
9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the metal-semiconductor interface structure design and contact characteristic analysis method as described in any one of claims 1 to 6.
10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the metal-semiconductor interface structure design and contact characteristic analysis method as described in any one of claims 1 to 6.