A method and device for designing an AlN / HfO2 interface structure
By establishing and optimizing the AlN/HfO2 interface model, calculating the electron trapping energy and hole trapping energy, interface structures with high electron trapping capabilities can be quickly screened out, solving the problem of difficult screening in existing technologies and improving experimental efficiency.
Patent Information
- Application Number
- CN202310630017.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-05-26
- Publication Date
- 2025-12-19
- Estimated Expiration
- 2043-05-26
AI Technical Summary
Existing technologies cannot quickly screen AlN/HfO2 interface structures with high electron-trapping capabilities, making experimental data difficult to analyze and wasting a lot of time.
By establishing a first interface model of AlN/HfO2, structural optimization was performed, and the electron trapping energy and hole trapping energy were calculated to determine the interface structure with high electron trapping energy.
This method enables the rapid screening of interface structures with high electron-capturing capabilities, solves the problem of difficult experimental data analysis, and improves experimental efficiency.
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Figure CN116646034B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of AlN / HfO2 interface structure design, in particular to an AlN / HfO2 interface structure design method and device. BACKGROUND
[0002] HfO2 is a high-dielectric-constant oxide, which is widely used as a charge trapping layer in FLASH memory devices. However, as the device size is scaled down, the thickness of HfO2 is reduced, and the trapped electrons are easy to escape, thereby causing device failure, so it is necessary to use a stacked gate structure to adjust the defect distribution in the HfO2 trapping layer and improve the charge trapping capacity. AlN has high electron affinity and can be used to adjust the defect distribution in the HfO2 trapping layer and improve the data retention capability of the device. The AlN / HfO2 interface has a great influence on the data retention capability of the device, and the deeper the electron defect level of the interface is, the more difficult the trapped electrons are to escape. Therefore, how to quickly obtain an AlN / HfO2 interface structure with high electron trapping capacity is an important technical challenge. In the prior art, it is impossible to quickly screen the interface structure with high electron trapping capacity, which causes the experimental data to be difficult to analyze and a large amount of time to be wasted. SUMMARY
[0003] Therefore, it is necessary to provide an AlN / HfO2 interface structure design method and device to solve the problem that the prior art cannot quickly screen the interface structure with high electron trapping capacity, which causes the experimental data to be difficult to analyze and a large amount of time to be wasted.
[0004] In one aspect, the application provides an AlN / HfO2 interface structure design method, which comprises the following steps:
[0005] establishing a first interface model of AlN / HfO2 according to the interface structure of AlN and the interface structure of HfO2;
[0006] performing structure optimization on the interface structure of the first interface model to obtain a preset number of second interface models; wherein the oxygen content in the interface structure corresponding to each second interface model is different;
[0007] performing structure optimization on the interface structure corresponding to each second interface model to obtain an energy value corresponding to each second interface model; and calculating the electron trapping energy and the hole trapping energy corresponding to each second interface model according to the energy value;
[0008] determining the interface structure corresponding to a third interface model with high electron trapping energy according to the electron trapping energy and the hole trapping energy.
[0009] In some possible implementation manners, the first interface model of AlN / HfO2 is established according to the interface structure of AlN and the interface structure of HfO2, and the method comprises the following steps.
[0010] The interface structure of HfO2 is subjected to rotation processing to obtain a rotated interface structure of HfO2.
[0011] The dangling bonds at the upper and lower ends of the heterojunction of the rotated interface structure of HfO2 and the interface structure of AlN are passivated according to pseudo-hydrogen, to obtain the first interface model of AlN / HfO2.
[0012] In some possible implementation manners, the interface structure of the first interface model is subjected to structure optimization to obtain a preset number of second interface models, and the method comprises the following steps.
[0013] A running parameter of first-principle calculation software VASP is set.
[0014] According to the running parameter, the interface structure of the first interface model is subjected to atomic position optimization by the first-principle calculation software VASP, to obtain a second interface model.
[0015] In a case where stable energy between the interface structure of AlN and the interface structure of HfO2 in the second interface model is less than a first preset threshold, all obtained second interface models are output.
[0016] In some possible implementation manners, the interface structure of the first interface model is subjected to structure optimization to obtain a preset number of second interface models, and the method further comprises the following steps.
[0017] In a case where the stable energy between the interface structure of AlN and the interface structure of HfO2 in the second interface model is not less than a first preset threshold, oxygen atoms connected between the interface structure of AlN and the interface structure of HfO2 in the second interface model are removed, to obtain a fourth interface model.
[0018] The first interface model is switched to the fourth interface model, and the step of “according to the running parameter, the interface structure of the first interface model is subjected to atomic position optimization by the first-principle calculation software VASP, to obtain a second interface model” is re-executed.
[0019] In some possible implementation manners, the interface structure corresponding to each second interface model is subjected to structure optimization to obtain an energy value corresponding to each second interface model, and the method comprises the following steps.
[0020] The first-principle calculation software VASP performs non-static self-consistent calculation on each of the second interface models respectively, and performs partitioning to obtain the valence band top position and the conduction band bottom position of the interface structure corresponding to each of the second interface models.
[0021] In some possible implementation manners, the calculation of the electron capture energy and the hole capture energy corresponding to each of the second interface models according to the energy value includes:
[0022] The first-principle calculation software VASP calculates the energy of each of the second interface models after capturing one electron, the energy after capturing one hole, and the energy without electricity respectively;
[0023] According to an electron capture energy formula, the conduction band bottom position, the energy after capturing one electron, and the energy without electricity of each of the second interface models are calculated to obtain the electron capture energy of each of the second interface models;
[0024] According to an electron capture energy formula, the conduction band bottom position, the energy after capturing one electron, and the energy without electricity of each of the second interface models are calculated to obtain the electron capture energy of each of the second interface models;
[0025] In some possible implementation manners, the determination of the interface structure corresponding to the third interface model with high electron capture energy according to the electron capture energy and the hole capture energy includes:
[0026] The second interface model with the maximum electron capture energy and the minimum hole capture energy in the preset number of second interface models is determined as the third interface model;
[0027] The interface structure of the third interface model is determined as the interface structure with high electron capture energy.
[0028] In some possible implementation manners, the electron capture energy formula is:
[0029] E electron = E CBM - (E q＝-1 - E q＝0 )
[0030] In the formula, E electron denotes the electron capture energy of the second interface model, E CBM denotes the conduction band bottom position of the second interface model, E q＝-1 denotes the energy of the second interface model after capturing one electron, and E q＝0 denotes the energy of the second interface model without electricity.
[0031] In some possible implementations, the hole capture energy formula is:
[0032] E hole = (E q＝0 -E q＝+1 )-E VBM
[0033] In the formula, E hole represents the hole capture energy of the second interface model, E VBM represents the valence band top position of the second interface model, E q＝+1 represents the energy of the second interface model after capturing one hole, E q＝0 represents the energy of the second interface model when not charged.
[0034] In another aspect, the present application also provides an AlN / HfO2 interface structure design device, comprising:
[0035] a model establishing module, configured to establish a first interface model of AlN / HfO2 according to the interface structure of AlN and the interface structure of HfO2;
[0036] a model optimizing module, configured to perform structure optimization on the interface structure of the first interface model to obtain a preset number of second interface models; wherein the oxygen content in the interface structure corresponding to each second interface model is different;
[0037] an energy value calculating module, configured to perform structure optimization on the interface structure corresponding to each second interface model to obtain an energy value corresponding to each second interface model; and calculate the electron capture energy and the hole capture energy corresponding to each second interface model according to the energy value;
[0038] a structure determining module, configured to determine the interface structure corresponding to a third interface model with high electron capture energy according to the electron capture energy and the hole capture energy.
[0039] The beneficial effects of the above embodiment are that the AlN / HfO2 interface structure design method provided by the application establishes a first interface model of AlN / HfO2 according to the interface structure of AlN and the interface structure of HfO2; the interface structure of the first interface model is optimized to obtain a preset number of second interface models with different oxygen contents in the interface structure; and the interface structure corresponding to each second interface model is optimized to obtain an energy value corresponding to each second interface model; so that the electron capture energy and the hole capture energy corresponding to each second interface model can be calculated according to the energy value; and the interface structure corresponding to a third interface model with high electron capture energy can be determined according to the electron capture energy and the hole capture energy, which realizes rapid screening of the interface structure with high electron capture capacity and solves the problem of being unable to rapidly screen the interface structure with high electron capture capacity, leading to difficulty in analyzing experimental data and wasting a large amount of time. BRIEF DESCRIPTION OF DRAWINGS
[0040] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.
[0041] Figure 1 An embodiment flowchart of the AlN / HfO2 interface structure design method provided by the application;
[0042] Figure 2 An interface structure diagram of the AlN interface structure and the HfO2 interface structure provided by the application;
[0043] Figure 3 An interface structure diagram of the O8 model to the O3 model provided by the application;
[0044] Figure 4 A density of states diagram of the O8 model to the O3 model provided by the application;
[0045] Figure 5 An electron capture energy diagram of the O8 model to the O3 model provided by the application;
[0046] Figure 6 A hole capture energy diagram of the O8 model to the O3 model provided by the application;
[0047] Figure 7 An embodiment structure diagram of the AlN / HfO2 interface structure design device provided by the application;
[0048] Figure 8An embodiment structure schematic diagram of an electronic device provided by the present application is shown in the figure. DETAILED DESCRIPTION
[0049] The technical solutions in the embodiments of the present application will be clearly and completely described in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person skilled in the art without creative work fall within the protection scope of the present application.
[0050] Some block diagrams shown in the figures are functional entities, which do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.
[0051] Reference to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to other embodiments. It is explicitly and implicitly understood by a person skilled in the art that the embodiments described herein can be combined with other embodiments.
[0052] The embodiments of the present application provide an AlN / HfO2 interface structure design method and device, which are described below respectively.
[0053] Figure 1 An embodiment flowchart of an AlN / HfO2 interface structure design method provided by the present application is shown in the figure, which includes the following steps. Figure 1
[0054] S101, a first interface model of AlN / HfO2 is established according to the interface structure of AlN and the interface structure of HfO2;
[0055] S102, the interface structure of the first interface model is optimized to obtain a preset number of second interface models; wherein the oxygen content in the interface structure corresponding to each second interface model is different;
[0056] S103, the interface structure corresponding to each second interface model is optimized to obtain an energy value corresponding to each second interface model; according to the energy value, an electron capture energy and a hole capture energy corresponding to each second interface model are calculated;
[0057] S104. Based on the electron trapping energy and the hole trapping energy, determine the interface structure corresponding to the third interface model with high electron trapping energy.
[0058] Compared with existing technologies, the AlN / HfO2 interface structure design method provided by this invention establishes a first interface model of AlN / HfO2 based on the interface structures of AlN and HfO2; optimizes the interface structure of the first interface model to obtain a predetermined number of second interface models with different oxygen contents; further optimizes the interface structure corresponding to each second interface model to obtain the energy value corresponding to each second interface model; thereby, the electron trapping energy and hole trapping energy corresponding to each second interface model can be calculated based on the energy value; and the interface structure corresponding to the third interface model with high electron trapping energy can be determined based on the electron trapping energy and hole trapping energy. This enables rapid screening of interface structures with high electron trapping capabilities, solving the problem that the inability to quickly screen interface structures with high electron trapping capabilities leads to difficult analysis of experimental data and wastes a lot of time.
[0059] In some embodiments of the present invention, step S101 includes:
[0060] The interface structure of HfO2 is rotated to obtain the rotated interface structure of HfO2.
[0061] The first interface model of AlN / HfO2 is obtained by passivating the dangling bonds at the top and bottom of the heterojunction between the HfO2 rotating interface structure and the AlN interface structure using pseudohydrogen.
[0062] It should be noted that, in order to avoid lattice mismatch at the interface, the interface structure of HfO2 can be rotated clockwise or counterclockwise. The specific rotation method and degree can be set according to the actual situation, and this embodiment of the invention does not impose any restrictions.
[0063] After rotation, the interface structure of HfO2 can be matched with the interface structure of AlN. In order to connect the interface structures of HfO2 and AlN, the dangling bonds at the top and bottom of the heterojunction of the interface structures of HfO2 and AlN can be pseudo-hydrogen passivated to obtain the first interface model of AlN / HfO2.
[0064] In a specific embodiment of the present invention, the HfO2 surface can be rotated 26.52° clockwise to match the AlN surface, such as... Figure 2 As shown, Figure 2 In the diagram, (A) represents the interface structure of AlN, and (B) represents the interface structure of HfO2. Figure 2It can be seen that the lattice mismatch degree of the interface is 2.87%, 16 layers of AlN material (8 layers of Al atoms and 8 layers of N atoms) and 11 layers of HfO2 material (5 layers of Hf atoms and 6 layers of O atoms) are selected to simulate the characteristics of AlN and HfO2 bulk materials, and the N and O on the upper and lower interfaces of the heterojunction are passivated by pseudo-hydrogen with 0.75 valence electrons and 0.5 valence electrons respectively.
[0065] In some embodiments of the present application, step S102 comprises:
[0066] setting the running parameters of the first-principles calculation software VASP;
[0067] optimizing the atomic positions of the interface structure of the first interface model by the first-principles calculation software VASP according to the running parameters to obtain a second interface model;
[0068] in the case that the stable energy between the interface structure of the AlN and the interface structure of the HfO2 in the second interface model is less than a first preset threshold, outputting all the obtained second interface models.
[0069] It should be noted that the running parameters of the first-principles calculation software VASP can include a cutoff energy, K points, electronic convergence accuracy and ion convergence accuracy, etc. The first interface model can be input into the first-principles calculation software VASP with the set running parameters. The first-principles calculation software VASP can obtain a stable interface structure through atomic position relaxation to obtain a second interface model. It can also be judged whether the stable energy between the interface structure of the AlN and the interface structure of the HfO2 in the second interface model is less than the first preset threshold. If yes, it indicates that the connection between the interface structure of the AlN and the interface structure of the HfO2 is not stable enough, and the connected oxygen atoms are already very few, and cannot be removed. Therefore, all the second interface models in the above steps can be obtained.
[0070] In specific embodiments of the present application, the cutoff energy can be set to 500 eV, the K points can be set to 3x3x1, the electronic convergence accuracy can be set to 1E-5, and the ion convergence accuracy can be set to 1E-2.
[0071] In some embodiments of the present application, step S102 further comprises:
[0072] in the case that the stable energy between the interface structure of the AlN and the interface structure of the HfO2 in the second interface model is not less than the first preset threshold, removing the connected oxygen atoms between the interface structure of the AlN and the interface structure of the HfO2 of the second interface model with the second preset threshold to obtain a fourth interface model;
[0073] Switching the first interface model to the fourth interface model, re-executing the step of "performing atomic position optimization on the interface structure of the first interface model by the first-principles calculation software VASP according to the running parameters to obtain a second interface model".
[0074] It should be noted that if the stable energy between the interface structure of AlN and the interface structure of HfO2 in the second interface model is not less than the first preset threshold, it indicates that the oxygen atoms connected between the interface structure of AlN and the interface structure of HfO2 in the second interface model of the second preset threshold can be removed to obtain a fourth interface model, the first interface model is switched to the fourth interface model, and then the step of "performing atomic position optimization on the interface structure of the first interface model by the first-principles calculation software VASP according to the running parameters to obtain a second interface model" is re-executed. The process is repeated to obtain a preset number of second interface models. The first preset threshold and the second preset threshold can be set according to actual conditions, which are not limited in the embodiments of the present application.
[0075] In the embodiments of the present application, the first preset threshold can be 3, and the second preset threshold can be 1, as shown in the following table. Figure 3 Figure 3 All the models in the table are second interface models, the oxygen atoms connected between the interface structure of AlN and the interface structure of HfO2 in the second interface model (a) are 8, so it is an O8 model. Since the 8 oxygen atoms are greater than the first preset threshold 3, all the oxygen atoms of the second preset threshold need to be removed. Therefore, the oxygen atoms connected between the interface structure of AlN and the interface structure of HfO2 are 7, obtaining a fourth interface model. Then the first interface model is switched to the fourth interface model, and the above processing process is repeated to obtain a second interface model (b). The oxygen atoms connected between the interface structure of AlN and the interface structure of HfO2 in the second interface model (b) are 7, so it is an O7 model. Similarly, an O6 model, an O5 model, an O4 model and an O3 model can be obtained. The oxygen atoms connected between the interface structure of AlN and the interface structure of HfO2 in the O3 model are 3, which is consistent with the first preset threshold. Therefore, the O8 model, the O7 model, the O6 model, the O5 model, the O4 model and the O3 model are output.
[0076] In some embodiments of the present application, the step S103 comprises:
[0077] According to the first-principles calculation software VASP, non-static self-consistent calculations are respectively performed on each second interface model, and division is performed to obtain the valence band top position and the conduction band bottom position of the interface structure corresponding to each second interface model.
[0078] It should be noted that the non-static self-consistent calculation refers to that the accurate state density is calculated by increasing the k points while keeping the atomic positions and charge density unchanged. The calculation is realized by the algorithm iteration in the first-principles calculation software VASP, and the non-static self-consistent calculation belongs to a kind of widely used calculation method.
[0079] In the embodiment of the present application, as shown in Figure 4 , Figure 4 the abscissa is the conduction band bottom (Energy), and the ordinate is the valence band top (Density of states). The state density diagrams of the O8 model, the O7 model, the O6 model, the O5 model, the O4 model and the O3 model obtained by non-static self-consistent calculation are extracted from the OUTCAR of Figure 4 the interface structure of each model.
[0080] In some embodiments of the present application, step S103 further comprises:
[0081] According to the first-principles calculation software VASP, the energy after capturing one electron, the energy after capturing one hole and the energy without electricity of each second interface model are calculated respectively;
[0082] According to the electron capture energy formula, the conduction band bottom position, the energy after capturing one electron and the energy without electricity of each second interface model are calculated respectively to obtain the electron capture energy of each second interface model.
[0083] According to the hole capture energy formula, the valence band top position, the energy after capturing one hole and the energy without electricity of each second interface model are calculated respectively to obtain the hole capture energy of each second interface model.
[0084] It should be noted that the electron capture energy formula is:
[0085] E electron = E CBM - (E q＝-1 - E q＝0 ) Formula 1
[0086] In the formula, E electron represents the electron capture energy of the second interface model, E CBM represents the conduction band bottom position of the second interface model, E q＝-1 represents the energy after capturing one electron of the second interface model, and E q＝0 represents the energy without electricity of the second interface model.
[0087] The hole capture energy formula is:
[0088] E hole =(E q＝0 -E q＝+1 )-E VBM Formula 2
[0089] In the formula, E hole E represents the hole trapping energy of the second interface model. VBM E represents the top position of the valence band in the second interface model. q＝+1 E represents the energy E generated when the second interface model captures a hole. q＝0 This represents the energy of the second interface model when it is uncharged.
[0090] In a specific embodiment of the present invention, different charge amounts can be q = +1 or q = -1.
[0091] In some embodiments of the present invention, step S104 includes:
[0092] The second interface model with the largest electron trapping energy and the smallest hole trapping energy among a preset number of second interface models is determined as the third interface model;
[0093] The interface structure of the third interface model is determined to be an interface structure with high electron capture energy.
[0094] It should be noted that if there exists an electron trapping energy that is the largest while the hole trapping energy is not the smallest, or if the electron trapping energy is not the largest while the hole trapping energy is the smallest, the third interface model can be determined according to actual needs.
[0095] In a specific embodiment of the present invention, such as Figure 5 As shown, Figure 5 The x-axis represents the O8 model versus the O3 model, and the y-axis represents the electron capture energy. The O8 model's interface structure has the greatest electron capture energy, such as... Figure 6 As shown, Figure 6 The horizontal axis represents the O8 model versus the O3 model, and the vertical axis represents the hole capture energy. The interface structure of the O8 model has the minimum hole capture energy. Therefore, the interface structure of the O8 model can be defined as an interface structure with high electron capture energy.
[0096] To better implement the AlN / HfO2 interface structure design method in this invention embodiment, based on the AlN / HfO2 interface structure design method, this invention embodiment also provides an AlN / HfO2 interface structure design device, such as... Figure 7 As shown, the AlN / HfO2 interface structure design device includes:
[0097] The model building module 701 is used to build the first interface model of AlN / HfO2 based on the interface structure of AlN and the interface structure of HfO2.
[0098] The model optimization module 702 is used to optimize the interface structure of the first interface model to obtain a preset number of second interface models; wherein the oxygen content in the interface structure of each second interface model is different.
[0099] The energy value calculation module 703 is used to perform structural optimization on the interface structure corresponding to each second interface model to obtain the energy value corresponding to each second interface model; and to calculate the electron trapping energy and hole trapping energy corresponding to each second interface model based on the energy value.
[0100] The structure determination module 704 is used to determine the interface structure corresponding to the third interface model with high electron trapping energy based on the electron trapping energy and the hole trapping energy.
[0101] The AlN / HfO2 interface structure design device provided in the above embodiments can realize the technical solutions described in the above AlN / HfO2 interface structure design method embodiments. The specific implementation principles of each module or unit can be found in the corresponding content in the above AlN / HfO2 interface structure design method embodiments, and will not be repeated here.
[0102] like Figure 8 As shown, the present invention also provides an electronic device 800. The electronic device 800 includes a processor 801, a memory 802, and a display 803. Figure 8 Only some components of the electronic device 800 are shown, but it should be understood that it is not required to implement all the components shown, and more or fewer components may be implemented instead.
[0103] In some embodiments, memory 802 may be an internal storage unit of electronic device 800, such as a hard disk or memory of electronic device 800. In other embodiments, memory 802 may also be an external storage device of electronic device 800, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. equipped on electronic device 800.
[0104] Furthermore, the memory 802 may include both internal storage units of the electronic device 800 and external storage devices. The memory 802 is used to store application software and various types of data installed on the electronic device 800.
[0105] The processor 801 may, in some embodiments, be a central processing unit (CPU), a microprocessor, or other data processing chip, for running program codes stored in the memory 802 or processing data, such as the AlN / HfO2 interface structure design method in the present application.
[0106] The display 803 may, in some embodiments, be an LED display, a liquid crystal display, a touch liquid crystal display, an OLED (Organic Light-Emitting Diode) touch, or the like. The display 803 is used to display information of the electronic device 800 and to display a visualized user interface. The components 801-803 of the electronic device 800 communicate with each other through a system bus.
[0107] It should be understood that, in addition to the above functions, the processor 801 may, when executing the functions in the memory 802, also implement other functions, which can be referred to the descriptions of the corresponding method embodiments.
[0108] Further, the type of the electronic device 800 referred to in the embodiments of the present application is not specifically limited, and the electronic device 800 can be a portable electronic device such as a mobile phone, a tablet computer, a personal digital assistant (PDA), a wearable device, a laptop, or the like. Exemplary embodiments of the portable electronic device include, but are not limited to, a portable electronic device running an IOS, an android, a microsoft, or other operating system. The above portable electronic device can also be other portable electronic devices, such as a laptop having a touch-sensitive surface (e.g., a touch panel), and the like. It should also be understood that, in some other embodiments of the present application, the electronic device 800 can also not be a portable electronic device, but a desktop computer having a touch-sensitive surface (e.g., a touch panel).
[0109] Correspondingly, the embodiments of the present application also provide a computer-readable storage medium for storing computer-readable programs or instructions, which, when executed by a processor, can implement the AlN / HfO2 interface structure design method steps or functions provided by the above method embodiments.
[0110] Those skilled in the art can understand that all or part of the processes of the above-mentioned embodiments can be completed by a computer program instructing related hardware (such as a processor, a controller, etc.) to complete. The computer program can be stored in a computer-readable storage medium. The computer-readable storage medium is a magnetic disk, an optical disk, a read-only memory, or a random access memory, etc.
[0111] The AlN / HfO2 interface structure design method and device provided by the present application are described in detail above, and the principles and implementation manners of the present application are described by using specific examples. The above description of the examples is only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation manners and application ranges will be changed, and the above description of the present application should not be understood as a limitation of the present application.
Claims
1. A method of designing an AlN / HfO2 interface structure, characterized by, The application relates to a method for determining an interface structure of an AlN / HfO2 interface, comprising the following steps: establishing a first interface model of AlN / HfO2 according to an interface structure of AlN and an interface structure of HfO2; performing structural optimization on the interface structure of the first interface model to obtain a preset number of second interface models; wherein the oxygen content in the interface structure corresponding to each second interface model is different; performing structural optimization on the interface structure corresponding to each second interface model to obtain an energy value corresponding to each second interface model; and calculating an electron capture energy and a hole capture energy corresponding to each second interface model according to the energy value; determining the interface structure corresponding to a third interface model with high electron capture energy according to the electron capture energy and the hole capture energy; the step of establishing a first interface model of AlN / HfO2 according to an interface structure of AlN and an interface structure of HfO2 comprises the following steps: performing rotation processing on the interface structure of HfO2 to obtain a rotated interface structure of HfO2; passivating the dangling bonds of the upper and lower ends of the heterojunction of the rotated interface structure of HfO2 and the interface structure of AlN according to pseudo-hydrogen to obtain a first interface model of AlN / HfO2; the step of performing structural optimization on the interface structure of the first interface model to obtain a preset number of second interface models comprises the following steps: setting the running parameters of first-principle calculation software VASP; performing atomic position optimization on the interface structure of the first interface model by the first-principle calculation software VASP according to the running parameters to obtain a second interface model; in the case that the stable energy between the interface structure of AlN and the interface structure of HfO2 in the second interface model is less than a first preset threshold value, outputting all obtained second interface models.
2. The AlN / HfO2 interface structure design method of claim 1, wherein, the step of performing structural optimization on the interface structure of the first interface model to obtain a preset number of second interface models further comprises the following steps: in the case that the stable energy between the interface structure of AlN and the interface structure of HfO2 in the second interface model is not less than a first preset threshold value, removing the oxygen atoms connected between the interface structure of AlN and the interface structure of HfO2 in the second interface model without the first preset threshold value to obtain a fourth interface model; switching the first interface model into the fourth interface model and re-executing the step of performing atomic position optimization on the interface structure of the first interface model by the first-principle calculation software VASP according to the running parameters to obtain a second interface model.
3. The AlN / HfO2 interface structure design method of claim 1, wherein, the step of performing structural optimization on the interface structure corresponding to each second interface model to obtain an energy value corresponding to each second interface model comprises the following steps: performing non-static self-consistent calculation on each second interface model by the first-principle calculation software VASP respectively and dividing to obtain the valence band top position and the conduction band bottom position of the interface structure corresponding to each second interface model.
4. The AlN / HfO2 interface structure design method of claim 3, wherein, the step of calculating an electron capture energy and a hole capture energy corresponding to each second interface model according to the energy value comprises the following steps: According to the first principle calculation software VASP, the energy of each second interface model after capturing one electron, the energy of each second interface model after capturing one hole and the energy of each second interface model without electricity are calculated respectively; According to the electron capture energy formula, the conduction band bottom position, the energy after capturing one electron and the energy without electricity of each second interface model are calculated respectively to obtain the electron capture energy of each second interface model. According to the electron capture energy formula, the conduction band bottom position, the energy after capturing one electron and the energy without electricity of each second interface model are calculated respectively to obtain the electron capture energy of each second interface model.
5. The AlN / HfO2 interface structure design method of claim 1, wherein, According to the electron capture energy formula, the conduction band bottom position, the energy after capturing one electron and the energy without electricity of each second interface model are calculated respectively to obtain the electron capture energy of each second interface model. The third interface model with high electron capture energy is determined according to the electron capture energy and the hole capture energy. The second interface model with the maximum electron capture energy and the minimum hole capture energy in the preset number of second interface models is determined as the third interface model.
6. The AlN / HfO2 interface structure design method of claim 4, wherein, The interface structure of the third interface model is determined as the interface structure with high electron capture energy. wherein the second interface model electron capture energy of the second interface model, the conduction band minimum position of the second interface model, the energy of the second interface model after capturing one electron, the energy of the second interface model when it is not charged.
7. The AlN / HfO2 interface structure design method of claim 4, wherein, The electron capture energy formula is: wherein represents the hole capture energy of the second interface model, represents the valence band maximum position of the second interface model, represents the energy of the second interface model after capturing one hole, represents the energy of the second interface model when it is not charged.
8. An AlN / HfO2 interface structure design apparatus, characterized by comprising: The hole capture energy formula is: It comprises: A model establishing module is configured to establish a first interface model of AlN / HfO2 according to the interface structure of AlN and the interface structure of HfO2; A model optimizing module is configured to perform structure optimization on the interface structure of the first interface model to obtain a preset number of second interface models; wherein the oxygen content in the interface structure corresponding to each second interface model is different; An energy value calculating module is configured to perform structure optimization on the interface structure corresponding to each second interface model to obtain an energy value corresponding to each second interface model; and calculate the electron capture energy and the hole capture energy corresponding to each second interface model according to the energy value; A structure determining module is configured to determine the interface structure corresponding to a third interface model with high electron capture energy according to the electron capture energy and the hole capture energy. The first interface model of AlN / HfO2 is established according to the interface structure of AlN and the interface structure of HfO2, which comprises: The interface structure of HfO2 is subjected to rotation processing to obtain a rotated interface structure of HfO2; The dangling bonds at the upper and lower ends of the heterojunction of the rotated interface structure of HfO2 and the interface structure of AlN are passivated according to pseudo-hydrogen to obtain the first interface model of AlN / HfO2; The structure optimization on the interface structure of the first interface model to obtain a preset number of second interface models comprises: The running parameters of the first principle calculation software VASP are set; The atomic position of the interface structure of the first interface model is optimized by the first principle calculation software VASP according to the running parameters to obtain a second interface model; In the case that the stable energy between the interface structure of AlN and the interface structure of HfO2 in the second interface model is less than a first preset threshold, all obtained second interface models are output.
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Method for forming an interface between germanium and other materials
US20060099782A1