Nanofluid-assisted monocrystalline silicon cutting method based on molecular dynamics simulation and computer system

Abstract

The invention relates to the technical field of computers, in particular to a nanofluid-assisted monocrystalline silicon cutting method based on molecular dynamics simulation and a computer system. A model of monocrystalline silicon, abrasive particles and nanofluid is established, cutting parameters in the nanofluid-assisted monocrystalline silicon cutting process are obtained through molecular dynamics simulation, the reduction effect of nanofluid-assisted lubrication on the machining temperature and stress is visually quantified, and therefore the feasibility and advantages of the nanofluid-assisted monocrystalline silicon cutting method are added. The invention aims to solve the problem of how to simulate nanofluid-assisted monocrystalline silicon cutting through molecular dynamics simulation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computer, in particular to a nanofluid assisted single crystal silicon cutting method based on molecular dynamics simulation and a computer system. BACKGROUND

[0002] As a commonly used semiconductor material, single crystal silicon is widely used in photovoltaic, electronic device and other fields. The processing quality of single crystal silicon has a crucial influence on the performance and reliability of subsequent components. Wire saw cutting is the main means of current single crystal silicon processing. Diamond abrasive particles are fixed on the surface of the metal wire, and single crystal silicon is repeatedly rubbed, and finally the single crystal silicon is sawn into a thin piece. However, in this process, the friction and wear between the abrasive particles and the single crystal silicon will directly affect the cutting efficiency and the surface quality of the single crystal silicon. In order to improve the cutting effect and reduce the friction, a lubricant is usually used to reduce friction and wear, cool the cutting area and take away part of the cutting chips.

[0003] In the related technical scheme, molecular dynamics simulation is a computer simulation method for studying the motion law of matter at the atomic and molecular scale. It can reveal the physical and chemical phenomena of materials in the processing process from the microscopic level, and provide theoretical guidance for optimizing processing technology, improving processing efficiency and material performance. Specifically applied to the wire saw cutting process of single crystal silicon, molecular dynamics simulation can deeply analyze the atomic interaction and mechanism in the wire saw cutting process under the lubrication of nanodiamond.

[0004] The inventors found that during the conception and implementation of the present application, nanodiamond (ND) fluid lubricant (hereinafter referred to as nanofluid) has unique physical and chemical properties, such as high hardness, good wear resistance and chemical stability. However, the current method lacks a nanofluid assisted single crystal silicon cutting method based on molecular dynamics simulation.

[0005] In view of this, the present application proposes a nanofluid assisted single crystal silicon cutting method based on molecular dynamics simulation, aiming to optimize the wire saw cutting process of single crystal silicon and provide technical support for the application of nanodiamond fluid lubrication in single crystal silicon cutting. SUMMARY

[0006] The main purpose of the present application is to provide a nanofluid assisted single crystal silicon cutting method based on molecular dynamics simulation, aiming to solve the problem of how to simulate nanofluid assisted single crystal silicon cutting through molecular dynamics simulation.

[0007] To achieve the above purpose, the present application provides a nanofluid assisted single crystal silicon cutting method based on molecular dynamics simulation, which comprises: S10, initializing a workpiece region and an abrasive region, wherein the workpiece region comprises a boundary layer, a constant temperature layer, a Newton layer and a fluid layer, the boundary layer is used to keep atoms fixed, the constant temperature layer is used to keep the temperature of atoms constant, the Newton layer is used to constrain atoms to follow Newton's second law, and the fluid layer is used to generate nanodiamond particles meeting a preset number and a preset size; S20, obtaining an atomic group identifier of a single crystal silicon workpiece to be cut, filling atoms with a first atomic group identifier to the boundary layer, the constant temperature layer and the Newton layer, filling atoms with a second atomic group identifier to the abrasive region, filling atoms with a third atomic group identifier and a fourth atomic group identifier to the fluid layer, and generating atoms with a fifth atomic group identifier as the nanodiamond particles in the fluid layer; S30, calling preset force field parameters to construct a force field, and setting constraints in the fluid layer to fix the bond length and bond angle of the nanodiamond particles, wherein the force field parameters comprise a Tersoff potential function and a Lennard-Jones potential function, the Tersoff potential function is used to simulate strong interaction between silicon-silicon covalent bonds and silicon-carbon covalent bonds, and the Lennard-Jones potential function is used to simulate weak interaction and electrostatic interaction; S40, calling an energy minimization function to minimize simulation energy; S50, obtaining a preset initial temperature, and adjusting the speed of all atoms in the abrasive region to a speed corresponding to the preset initial temperature; S60, calling a microcanonical constraint function to configure atoms in the Newton layer, the constant temperature layer and the fluid layer, and calling a canonical constraint function to configure atoms in the boundary layer; S70, starting a single crystal silicon cutting simulation process, obtaining cutting parameters generated in the single crystal silicon cutting simulation process, and cutting the single crystal silicon workpiece to be cut based on the cutting parameters.

[0008] Optionally, the atoms of the first atomic group identifier are silicon atoms, the atoms of the second atomic group identifier are carbon atoms, the atoms of the third atomic group identifier are oxygen atoms, the atoms of the fourth atomic group identifier are hydrogen atoms, and the atoms of the fifth atomic group identifier are nanodiamond atoms.

[0009] Optionally, before the step S10, the method further comprises: configuring basic parameters, wherein the basic parameters comprise a system unit system, a spatial dimension, a boundary condition, a time step, an atomic type and a neighbor list parameter configuration.

[0010] Optionally, in the step S10, the size of the workpiece region is 270x120x180 Å, and the size of the fluid layer is 270x120x5 Å.

[0011] Optionally, in S30, the potential type between the bond length and the bond angle is a harmonic potential, which is suitable for simulating the stretching effect between chemical bonds and the bending effect of the bond angle, wherein the force constant is set to 1000, the equilibrium bond length is set to 1 Å, and the equilibrium bond angle is set to 109.47 degrees. The constraints of the fluid layer include: the constraint precision is 1e-4, the maximum number of iterations is 10, the maximum number of attempts is 10000, and the atomic overlap removal instruction is set.

[0012] Optionally, in S40, the conjugate gradient method is used to set the energy minimization function.

[0013] Optionally, S60 includes: The microcanonical constraint function is called to keep the particle number, volume and energy of atoms in the Newton layer, the thermostat layer and the fluid layer constant. The canonical constraint function is called to keep the particle number, volume and energy of atoms in the boundary layer constant.

[0014] Optionally, the cutting parameters include temperature, norm equivalent stress, cutting force, dislocation, potential energy and kinetic energy distribution.

[0015] Optionally, in S70, the step of cutting the single crystal silicon workpiece to be cut based on the cutting parameters includes: According to the temperature, norm equivalent stress, cutting force, dislocation, potential energy and kinetic energy distribution in the cutting parameters, the target process parameters in the actual cutting process are determined, and the target process parameters include cutting speed, nanofluid volume fraction and nanofluid particle size. The cutting device is controlled to adjust to a running state meeting the target process parameters to perform a cutting operation on the single crystal silicon workpiece to be cut.

[0016] In addition, to achieve the above-mentioned purpose, the present application also provides a computer system, which comprises a memory, a processor and a computer program stored on the memory and executable on the processor, and the computer program is executed by the processor to realize the steps of the nanofluid-assisted single crystal silicon cutting method based on molecular dynamics simulation according to any one of the above.

[0017] The present application has at least the following beneficial effects: 1. Microscopic mechanism research is more in-depth: the present application simulates and simulates from a microscopic perspective based on molecular dynamics, compared with macroscopic research, the present application considers the unique effects of atoms at the microscopic level, explores the interaction between nanofluid and single crystal silicon at the microscopic level, is closer to real processing conditions, and the experimental results are more accurate.

[0018] 2. The cutting performance analysis is intuitive and reliable: the application establishes a model of single crystal silicon, abrasive particles and nanofluid, obtains stress and temperature cloud maps in the cutting process through molecular dynamics simulation, intuitively quantifies the reduction effect of nanofluid assisted lubrication on processing temperature and stress, and proves the feasibility and advantages of the method of adding nanofluid to assist in cutting single crystal silicon.

[0019] 3. Reduce experimental cost: the experimental conditions of single crystal silicon wire saw cutting are harsh, and the establishment of the experimental platform requires high cost, the simulation method of the application is suitable for Windows and Linux systems, the computing environment is flexible, a large number of actual cutting experiments are not needed, and the experimental cost is significantly reduced and the experimental time is saved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 A flowchart of the nanofluid assisted single crystal silicon cutting method based on molecular dynamics simulation involved in the embodiments of the application; Figure 2 A molecular dynamics simulation model diagram of simulating nanofluid assisted cutting of single crystal silicon involved in the embodiments of the application; Figure 3 A molecular dynamics simulation model diagram of simulating nanofluid assisted cutting of single crystal silicon involved in the embodiments of the application; Figure 4 A motion trajectory profile diagram of simulating nanofluid assisted cutting of single crystal silicon involved in the embodiments of the application; Figure 5 A temperature distribution cloud map of nanofluid assisted cutting of single crystal silicon involved in the embodiments of the application; Figure 6 A temperature distribution cloud map of nanofluid assisted cutting of single crystal silicon involved in the embodiments of the application; Figure 7 A stress distribution cloud map of nanofluid assisted cutting of single crystal silicon involved in the embodiments of the application; Figure 8 A stress distribution cloud map of nanofluid assisted cutting of single crystal silicon involved in the embodiments of the application; Figure 9 An architecture diagram of a hardware running environment of a computer system involved in the embodiments of the application.

[0021] The implementation, functional features and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0022] For a better understanding of the above technical solutions, the exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0023] First embodiment With reference to Figure 1 In this embodiment, a nanofluid-assisted single crystal silicon cutting method based on molecular dynamics simulation is provided. In this embodiment, the molecular dynamics simulation environment parameters for nanodiamond-assisted cutting are set using LAMMPS software.

[0024] As an optional pre-procedure, basic parameters are configured, including: system unit, spatial dimension, boundary condition, time step, atom type, and neighbor list parameter configuration. Specifically, the system unit is metal, the spatial dimension is three-dimensional, the boundary condition is ppp periodic boundary condition, and the time step is set to 0.005 ps. Since water molecules have bond angles, the atom type is set to full, and the neighbor list update rule is to start updating after 5 steps, and then update the neighbor list once every 1 step. The method comprises the following steps: S10, initializing the workpiece area and the abrasive area, wherein the workpiece area comprises a boundary layer, a constant temperature layer, a Newton layer, and a fluid layer, the boundary layer is used to keep the atoms fixed, the constant temperature layer is used to keep the atom temperature constant, the Newton layer is used to constrain the atoms to follow Newton's second law, and the fluid layer is used to generate nanodiamond particles meeting the preset number and size; In this embodiment, the established workpiece area and abrasive area are first initialized. The boundary layer, constant temperature layer, Newton layer, and fluid layer of the single crystal silicon workpiece are established respectively, and after the establishment of each area, they are combined into a workpiece area using the unio instruction, wherein the boundary layer keeps the atoms fixed, the constant temperature layer keeps the atom temperature constant, and the Newton layer keeps the atoms following Newton's second law.

[0025] In some optional embodiments, the size of the workpiece area is 270x120x5A, and the established abrasive area has a radius of 20A.

[0026] In some optional embodiments, the size of the fluid layer is 270x120x5A, the label loop instruction is used to generate a specified number of nanodiamond particles, and the variable instruction is used to set the number and radius of the nanodiamond particles to be generated. The number can be set to 30 and the radius can be set to 6A.

[0027] S20, obtain an atomic group identifier of a single crystal silicon workpiece to be cut, fill atoms with a first atomic group identifier to the boundary layer, the constant temperature layer and the Newton layer, fill atoms with a second atomic group identifier to the abrasive grain area, fill atoms with a third atomic group identifier and a fourth atomic group identifier to the fluid layer, and generate atoms with a fifth atomic group identifier as the nanometer diamond particles in the fluid layer; In this embodiment, the lattice constant and the atomic mass of each type of atom in the single crystal silicon workpiece to be cut are configured in advance, and a unique atomic group identifier is assigned to each type of atom based on the type of the atom. After the initialization area is obtained, the atomic group identifier of the single crystal silicon workpiece to be cut is obtained, and the classification of the single crystal silicon workpiece to be cut is completed. The atoms with different identifiers are allocated to different positions in the workpiece area to complete the creation of the simulation box.

[0028] Further and optionally, the atoms with the first atomic group identifier represent silicon atoms, the atoms with the second atomic group identifier represent carbon atoms, the atoms with the third atomic group identifier represent oxygen atoms, the atoms with the fourth atomic group identifier represent hydrogen atoms, and the atoms with the fifth atomic group identifier represent nanometer diamond atoms.

[0029] In addition, during the creation of the simulation box, 3000 water molecules are filled in the fluid layer by reading a water molecule template (an SPC / E water molecule model is used in this embodiment) and using a molecule instruction to read the template.

[0030] S30, call a preset force field parameter to construct a force field, and set a constraint in the fluid layer to fix the bond length and the bond angle of the nanometer diamond particles, wherein the force field parameter includes a Tersoff potential function and a Lennard-Jones potential function, the Tersoff potential function is used to simulate the strong interaction between silicon-silicon covalent bonds and silicon-carbon covalent bonds, and the Lennard-Jones potential function is used to simulate weak interaction and electrostatic interaction; In this embodiment, after the creation of the simulation box is completed, the preset force field parameter is called to complete the initialization of the force field.

[0031] Optionally, the type of the interaction potential between the bond length and the bond angle is a harmonic potential, which is suitable for simulating the stretching action between chemical bonds and the bending action of chemical bond angles, wherein the force constant is set to 1000, the equilibrium bond length is set to 1 Å, and the equilibrium bond angle is set to 109.47 degrees. The constraint set in the fluid layer includes: the constraint accuracy is 1e-4, the maximum number of iterations is 10, the maximum number of attempts is 10000, and the clear atomic overlap instruction is set.

[0032] S40, call an energy minimization function to minimize the simulation energy; In this step, energy minimization is performed on all atoms in the system to eliminate unreasonable structures in the model.

[0033] In some alternative implementations, the min_style directive is used to set the energy minimization method, which is the conjugate gradient method (cg), and the minimize directive is used to perform energy minimization.

[0034] S50, obtain a preset initial temperature, and adjust the velocity of all atoms in the abrasive region to the velocity corresponding to the preset initial temperature; In this step, after minimizing the energy, temperature initialization is performed. The temperature of the system is calculated based on the atomic velocities, so temperature initialization is equivalent to initializing the atomic velocities.

[0035] In some alternative implementations, the initial temperature is preset to 300K, and the velocity instruction is used to assign an initial velocity to all atoms.

[0036] S60, call the micro-regular constraint function to configure the atoms in the Newton layer, the isothermal layer, and the fluid layer, and call the regular constraint function to configure the atoms in the boundary layer; This step involves relaxation. The atoms in the Newtonian layer, isothermal layer, and fluid layer are set to micro-canonical constraints (NVE), i.e., constant particle number N, volume V, and energy E, with no temperature control. Other atoms are set to canonical constraints (NVT), i.e., constant particle number N, volume V, and temperature T. This allows for full relaxation of the simulation system, minimizing system energy and achieving a stable structure. The boundary layer is fixed, with atomic velocities and forces set to 0 to reduce boundary effects.

[0037] In some alternative implementations, "Berendsen" temperature control is set for the atoms in the isothermal layer, with a target temperature of 100K and a temperature coupling coefficient of 0.1.

[0038] S70, start the monocrystalline silicon cutting simulation process, obtain the cutting parameters generated in the monocrystalline silicon cutting simulation process, and cut the monocrystalline silicon workpiece to be cut based on the cutting parameters.

[0039] In this embodiment, after completing the above steps, a single-crystal silicon cutting simulation process is started to obtain the cutting parameters generated in the single-crystal silicon cutting simulation process, so as to cut the single-crystal silicon workpiece to be cut based on the cutting parameters.

[0040] In some alternative implementations, the cutting parameters include temperature, paradigmatic equivalent stress, cutting force, dislocations, and potential and kinetic energy distribution.

[0041] In some alternative implementations, the spherical abrasive particles are set to move horizontally along the negative x-axis, the output results are processed and recorded, and the OVITO software is used for visualization.

[0042] In some alternative implementations, the target process parameters in the actual cutting process are determined based on the temperature, paradigm equivalent stress, cutting force, dislocation, potential energy and kinetic energy distribution in the cutting parameters. The target process parameters include cutting speed, nanofluid volume fraction and nanofluid particle size. The cutting equipment is controlled to operate in a state that meets the target process parameters in order to perform a cutting operation on the monocrystalline silicon workpiece to be cut.

[0043] For example, refer to Figures 2-8 The following diagrams are shown respectively: molecular dynamics simulation model diagram of simulating nanofluid-assisted cutting of single-crystal silicon, molecular dynamics simulation model diagram of simulating non-fluid-assisted cutting of single-crystal silicon, motion trajectory profile diagram of simulating nanofluid-assisted cutting of single-crystal silicon, temperature distribution cloud map of nanofluid-assisted cutting of single-crystal silicon, temperature distribution cloud map of non-nanofluid-assisted cutting of single-crystal silicon, stress distribution cloud map of nanofluid-assisted cutting of single-crystal silicon, and stress distribution cloud map of non-nanofluid-assisted cutting of single-crystal silicon.

[0044] Specifically, Figure 2 This is a molecular dynamics simulation model of nanofluid-assisted cutting of single-crystal silicon. The workpiece part is divided into a boundary layer (red), a isothermal layer (blue), and a Newtonian layer (yellow). The fluid layer region contains ND particles (green) and water molecules (light blue). In the figure, the water molecules exhibit a non-uniform aggregated distribution after passing through the energy minimum and forming a discrete cluster structure. The abrasive particles are spherical (purple).

[0045] Figure 3 This is a simulation model of molecular dynamics of dry cutting of single-crystal silicon without nanofluid assistance. The workpiece region and the abrasive region in the figure are shown. Figure 2 Consistent with the simulated dry cutting state, forming a contrast with nanofluid-assisted cutting.

[0046] Figure 4 This is a cross-sectional view of the motion trajectory of nanofluid-assisted cutting of single-crystal silicon. In the figure, the abrasive particles move horizontally along the negative x-axis, simulating the process of abrasive particles cutting single-crystal silicon.

[0047] Figure 5 and Figure 6 The atomic temperature distribution cloud maps of the two models show that the high-temperature region is mainly concentrated at the crescent-shaped surface where the abrasive grains contact the workpiece. The atomic temperature during nanofluid-assisted cutting is lower than that during dry cutting, and the range of the high-temperature region is smaller than that during dry cutting. This proves that nanofluid-assisted cutting of single-crystal silicon has heat conduction and cooling effects.

[0048] Figure 7 With Figure 8 The two atomic stress distribution clouds are provided for two models. By comparing the two clouds, it can be seen that the stress is mainly concentrated at the contact between the abrasive particles and the workpiece, and the stress range is smaller and the strength is weaker under the nanofluid assisted cutting, which shows that the nanofluid assisted cutting of single crystal silicon has the effects of buffering and lubrication.

[0049] In the technical scheme provided in the embodiment, a model of single crystal silicon, abrasive particles and nanofluid is established, the cutting parameters in the nanofluid assisted single crystal silicon cutting process are obtained through molecular dynamics simulation, the reduction effect of the nanofluid assisted lubrication on the processing temperature and stress is quantified intuitively, and thus the feasibility and advantages of the nanofluid assisted single crystal silicon cutting method are added.

[0050] Second embodiment Based on the first embodiment, in the embodiment, the single crystal silicon can be replaced by other hard and brittle materials such as silicon carbide, single crystal copper and the like, the numerical values of the temperature, linear speed and the like of the processing process depend on the experience of the processing personnel, and the potential function of the replaced material is replaced by the potential function suitable for the material. Or the nanodiamond particles in the fluid are replaced by other nanoparticles such as Al2O3, SiO2 and the like, and other steps remain unchanged.

[0051] As an implementation scheme, Figure 9 The figure is a schematic diagram of the architecture of the hardware running environment of the computer system related to the embodiment scheme of the application.

[0052] As Figure 9 shown, the computer system can include a processor 1001 such as a CPU, a memory 1005, a user interface 1003, a network interface 1004 and a communication bus 1002. The communication bus 1002 is used to realize the connection and communication between the components. The user interface 1003 can include a display screen (Display) and an input unit such as a keyboard (Keyboard). The optional user interface 1003 can also include a standard wired interface and a wireless interface. The network interface 1004 can optionally include a standard wired interface and a wireless interface (such as a WI-FI interface). The memory 1005 can be a high-speed RAM memory or a stable memory (non-volaatile memory) such as a magnetic disk memory. The memory 1005 can also be a storage device independent of the aforementioned processor 1001.

[0053] Those skilled in the art can understand, Figure 9 The computer system architecture shown in the embodiment does not constitute a limitation on the computer system, and can include more or fewer components than the figure, or combine certain components, or different component arrangements.

[0054] AsFigure 9 As shown, the memory 1005 as a storage medium can include an operating system, a network communication module, a user interface module and a computer program. Among them, the operating system is a program that manages and controls the hardware and software resources of the computer system, and the running of the computer program and other software or programs.

[0055] In Figure 9 In the computer system shown, the user interface 1003 is mainly used to connect the terminal and communicate data with the terminal; the network interface 1004 is mainly used for the background server and communicates data with the background server; the processor 1001 can be used to call the computer program stored in the memory 1005.

[0056] In this embodiment, the computer system comprises a memory 1005, a processor 1001 and a computer program stored on the memory and executable on the processor, wherein: When the processor 1001 calls the computer program stored in the memory 1005, the following operations are performed: S10, initializing the workpiece area and the abrasive area, wherein the workpiece area comprises a boundary layer, a constant temperature layer, a Newton layer and a fluid layer, the boundary layer is used to keep the atoms fixed, the constant temperature layer is used to keep the atom temperature constant, the Newton layer is used to constrain the atoms to follow Newton's second law, and the fluid layer is used to generate nanodiamond particles meeting the preset number and size; S20, obtaining the atomic group identification of the single crystal silicon workpiece to be cut, filling the atoms with the first atomic group identification to the boundary layer, the constant temperature layer and the Newton layer, filling the atoms with the second atomic group identification to the abrasive area, filling the atoms with the third atomic group identification and the fourth atomic group identification to the fluid layer, and generating the atoms with the fifth atomic group identification as the nanodiamond particles in the fluid layer; S30, calling a preset force field parameter to construct a force field, and setting a constraint in the fluid layer to fix the bond length and bond angle of the nanodiamond particles, wherein the force field parameter comprises a Tersoff potential function and a Lennard-Jones potential function, the Tersoff potential function is used to simulate the strong interaction between silicon-silicon covalent bond and silicon-carbon covalent bond, and the Lennard-Jones potential function is used to simulate weak interaction and electrostatic interaction; S40, calling an energy minimization function to minimize the simulation energy; S50, obtaining a preset initial temperature, and adjusting the speed of all atoms in the abrasive area to the corresponding speed meeting the preset initial temperature; S60, calling a microcanonical constraint function to configure the atoms in the Newton layer, the constant temperature layer and the fluid layer, and calling a canonical constraint function to configure the atoms in the boundary layer. S70, start a single crystal silicon cutting simulation process, acquire a cutting parameter generated in the single crystal silicon cutting simulation process, and cut the single crystal silicon workpiece to be cut based on the cutting parameter.

[0057] It should be noted that the storage medium provided by the embodiments of the present application is a storage medium used to implement the method of the embodiments of the present application. Therefore, based on the method introduced in the embodiments of the present application, the specific structure and variations of the storage medium can be understood by those skilled in the art, and therefore will not be described here. Any storage medium used by the method of the embodiments of the present application belongs to the scope of protection of the present application.

[0058] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0059] The present application is described with reference to flowcharts and / or block diagrams according to the methods, devices (systems) and computer program products of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams can be implemented by computer program instructions, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus that performs the functions specified in one or more flows and / or blocks.

[0060] These computer program instructions can also be stored in a computer-readable memory that can guide the computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including instruction apparatus, which implements the functions specified in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus that performs the functions specified in one or more flows and / or blocks.

[0061] These computer program instructions can also be loaded into a computer or other programmable data processing device, so that a series of operation steps are performed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide a process for implementing the functions specified in the flowcharts and / or block diagrams. Figure 1One or more processes and / or boxes Figure 1 Figure 1 The steps of the function specified in one or more boxes.

[0062] It should be noted that any reference signs placed between parentheses in the claims should not be construed as limiting the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "a" or "an" preceding a component does not exclude the presence of a plurality of such components. This application can be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0063] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0064] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A nanofluid-assisted single-crystal silicon cutting method based on molecular dynamics simulation, characterized in that, The method includes the following steps: S10, initialize the workpiece region and the abrasive region, wherein the workpiece region includes a boundary layer, a thermostatic layer, a Newton layer and a fluid layer, the boundary layer is used to keep the atoms fixed, the thermostatic layer is used to keep the atomic temperature constant, the Newton layer is used to constrain the atoms to follow Newton's second law, and the fluid layer is used to generate nanodiamond particles that meet the preset number and preset size. S20: Obtain the atomic grouping identifier of the single crystal silicon workpiece to be cut; fill the boundary layer, the isothermal layer and the Newton layer with atoms bearing the first atomic grouping identifier; fill the abrasive region with atoms bearing the second atomic grouping identifier; fill the fluid layer with atoms bearing the third and fourth atomic grouping identifiers; and generate nanodiamond particles in the fluid layer using atoms bearing the fifth atomic grouping identifier. S30, a force field is constructed by calling preset force field parameters, and constraints are set in the fluid layer to fix the bond length and bond angle of the nanodiamond particles. The force field parameters include the Tersoff potential function and the Lanner-Jones potential function. The Tersoff potential function is used to simulate the strong interaction between silicon-silicon covalent bonds and silicon-carbon covalent bonds, and the Lanner-Jones potential function is used to simulate the weak interaction and electrostatic interaction. S40 calls the energy minimization function to minimize the simulation energy; S50, obtain a preset initial temperature, and adjust the velocity of all atoms in the abrasive region to the velocity corresponding to the preset initial temperature; S60, call the micro-regular constraint function to configure the atoms in the Newton layer, the isothermal layer, and the fluid layer, and call the regular constraint function to configure the atoms in the boundary layer; S70, start the monocrystalline silicon cutting simulation process, obtain the cutting parameters generated in the monocrystalline silicon cutting simulation process, and cut the monocrystalline silicon workpiece to be cut based on the cutting parameters.

2. The method as described in claim 1, characterized in that, The first atomic group identifier is characterized as silicon atoms, the second atomic group identifier is characterized as carbon atoms, the third atomic group identifier is characterized as oxygen atoms, the fourth atomic group identifier is characterized as hydrogen atoms, and the fifth atomic group identifier is characterized as nanodiamond atoms.

3. The method as described in claim 1, characterized in that, Before step S10, the method further includes: Configure basic parameters, including: system unit system, spatial dimension, boundary conditions, time step, atom type, and neighbor list parameter configuration.

4. The method as described in claim 1, characterized in that, In S10, the workpiece area has a size of 270×120×180Å, and the fluid layer has a size of 270×120×5Å.

5. The method as described in claim 1, characterized in that, In S30, the interaction potential between the bond length and the bond angle is a harmonic potential, which is suitable for simulating the stretching effect between chemical bonds and the bending effect of chemical bond angles. The force constant is set to 1000, the equilibrium bond length is set to 1 Å, and the equilibrium bond angle is set to 109.47 degrees. The constraints set for the fluid layer include: a constraint precision of 1e-4, a maximum number of iterations of 10, a maximum number of attempts of 10000, and a command to clear atomic overlaps.

6. The method as described in claim 1, characterized in that, In S40, the conjugate gradient method is used to set the energy minimization function.

7. The method as described in claim 1, characterized in that, The S60 includes: The micro-regular constraint function is invoked to keep the number of atoms, volume, and energy of atoms in the Newtonian layer, the isothermal layer, and the fluid layer constant. The regular constraint function is invoked to keep the number of atoms, volume, and energy temperature of atoms in the boundary layer constant.

8. The method as described in claim 1, characterized in that, The cutting parameters include temperature, paradigmatic equivalent stress, cutting force, dislocations, and potential and kinetic energy distribution.

9. The method as described in claim 8, characterized in that, In step S70, the step of cutting the single-crystal silicon workpiece based on the cutting parameters includes: Based on the temperature, paradigm equivalent stress, cutting force, dislocation, potential energy and kinetic energy distribution in the cutting parameters, the target process parameters in the actual cutting process are determined. The target process parameters include cutting speed, nanofluid volume fraction and nanofluid particle size. The cutting equipment is controlled to operate in a state that meets the target process parameters in order to perform a cutting operation on the monocrystalline silicon workpiece to be cut.

10. A computer system, characterized in that, The computer system includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps of the nanofluid-assisted single-crystal silicon cutting method based on molecular dynamics simulation as described in any one of claims 1 to 9.

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