A topology optimization method for main substrate of lithography machine

Abstract

The present application provides a topology optimization method for a main substrate of a lithography machine, belonging to the technical field of lithography machine manufacturing, comprising S1, constructing a simulation model of the main substrate; S2, setting design variables for topology optimization, and determining the design area and non-design area; S3, defining the objective function of the optimization, with minimum flexibility and maximum first-order modal frequency as the optimization goals; S4, defining control variable parameters to control the checkerboard phenomenon; and S5, optimizing the design area. By reasonably determining the design area and non-design area, using topology optimization simulation analysis software, and defining the optimization objective function and control variable parameters, the design area is optimized; thus, the design difficulty of the main substrate structure is greatly reduced, the design efficiency of the main substrate structure is improved, and the stability and reliability of the performance of the optimized main substrate structure are guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of photolithography machine manufacturing, and in particular to a topology optimization method for a main substrate of a photolithography machine. Background Art

[0002] The main baseplate is a critical component in a lithography machine, supporting multiple key subsystems, including the projection lens and measurement system. The stability of the main baseplate provides a strong guarantee for the normal operation of the entire system. To ensure optimal exposure stability for the lithography machine and the performance of each subsystem, a main baseplate frame with high strength, high rigidity, and excellent vibration damping is required.

[0003] In the existing technology, due to the high requirements for stability and reliability of lithography equipment, materials with high strength, high stiffness and high vibration damping performance are often used as the basis, such as certain alloys or composite materials, to ensure that they will not be deformed or damaged due to factors such as temperature changes and stress concentration during operation.

[0004] Currently, the main substrate structure of the lithography machine is mainly designed by experience or compared with multiple structures. This method is not only difficult and time-consuming in the early design, but also has no guarantee of performance, which easily leads to waste of manpower, material resources and other resources. Summary of the Invention

[0005] The purpose of this application is to solve the problems in the prior art of the design process of the main substrate structure of a lithography machine, which is difficult, has a long cycle, and the performance cannot be guaranteed, which easily leads to waste of manpower and material resources. Therefore, this application provides a topology optimization method for the main substrate of a lithography machine. By rationally determining the design area and non-design area, using topology optimization simulation analysis software, and defining the optimization objective function and control variable parameters, the design area is optimized; the design difficulty of the main substrate structure is greatly reduced, the design efficiency of the main substrate structure is improved, and the stability and reliability of the performance of the optimized main substrate structure are guaranteed.

[0006] The embodiment of the present application provides a topology optimization method for a main substrate of a lithography machine, comprising: S1, constructing a simulation model of the main substrate;

[0007] S2. Set the design variables for topology optimization and determine the design area and non-design area;

[0008] S3. Define the optimization objective function, with the minimum flexibility and the maximum first-order modal frequency as the optimization goals;

[0009] S4. defining control variable parameters to control the checkerboard phenomenon;

[0010] S5. Optimize the design area.

[0011] Using this technical solution, minimizing flexibility and maximizing first-order modal frequency are optimization goals. This ensures that the optimized main baseplate meets overall stiffness requirements while minimizing mass and manufacturing costs. Furthermore, maximizing first-order modal frequency ensures that the dynamic characteristics of the main baseplate meet design requirements.

[0012] In some embodiments, step S1 includes:

[0013] S11, establishing an initial structural model of the main substrate in a three-dimensional software, and importing it into a simulation analysis software to perform mesh division, material property assignment, and preliminary mesh assembly to establish the finite element simulation model;

[0014] S12, determining multiple working conditions of the simulation model;

[0015] S13. Determine the corresponding model load condition and corresponding boundary conditions according to the working condition;

[0016] S14. According to the working conditions, static and modal calculations are performed on the simulation model to obtain stress distribution and modal frequency of the main substrate under multiple working conditions.

[0017] By adopting the above technical solution and constructing a finite element simulation model, the design difficulty of the main substrate structure can be reduced and the design efficiency of the main substrate structure can be improved; and the model load conditions, corresponding boundary conditions, main substrate stress distribution and modal frequency can be determined in combination with the actual operating conditions of the main substrate, thereby ensuring the feasibility and rationality of topology optimization.

[0018] In some embodiments, step S2 includes:

[0019] S21, the simulation model adopts a symmetrical structure and is provided with a single one-dimensional symmetry constraint;

[0020] S22: setting the interface area of ​​the simulation model as a non-design area, and setting other areas of the simulation model as design areas.

[0021] By adopting the above technical solution, only the interface area can be set as the non-design area, thereby ensuring the maximization of the optimization space; and the simulation model adopts a symmetrical structure and is provided with a single one-dimensional symmetry constraint; thereby facilitating actual casting based on the optimized simulation model, thereby reducing the manufacturing cost of the main substrate.

[0022] In some embodiments, step S3 includes:

[0023] S31. Taking minimum flexibility as the optimization goal and setting the upper limit of the material removal volume constraint ratio to 20%, a main substrate topology optimization model with minimum flexibility as the optimization goal is established.

[0024] In some embodiments, step S4 includes:

[0025] S41: Perform maximum and minimum member control, set the minimum member control to 2-3 times the grid size, and the maximum member control to less than 6 times the grid size;

[0026] S42: Set the CHECKER parameter to control the checkerboard phenomenon. When the CHECKER parameter value is 0, it indicates that the checkerboard phenomenon is not controlled; when the CHECKER parameter value is 1, it indicates that the entire checkerboard is controlled;

[0027] S43: Set the discrete parameter DISCRETE, set the default value of the discrete parameter DISCRETE to 1, and the solid element to 3.

[0028] In some embodiments, the main substrate includes a main board and a plurality of support columns supporting the main board; the non-design area includes a first non-design area and a second non-design area;

[0029] The center of the main board is provided with an objective lens through hole, and a plurality of circular objective lens interfaces surrounding the objective lens through hole;

[0030] The mainboard is also provided with a plurality of gantry interfaces arranged in a rectangular plane;

[0031] The annular area simultaneously covering the plurality of objective lens interfaces is set as a first non-design area, and the gantry interface area is directly set as a second non-design area;

[0032] Other areas of the mainboard and the plurality of support columns are set as the designed areas.

[0033] In some embodiments, the simulation analysis software is configured as an Optistruct platform.

[0034] In some embodiments, step S6 is further included, wherein step S6 includes:

[0035] Redesigning the main base plate according to the topology optimization results;

[0036] The redesigned main base plate is subjected to structural strength analysis to determine whether it meets the design requirements. If so, the topology optimization is completed; if not, the redesigned main base plate is subjected to secondary optimization.

[0037] In some embodiments, the step of performing secondary optimization on the redesigned master substrate includes:

[0038] The non-design area is expanded outward based on the original non-design area; wherein the expansion distance is determined based on the average value of the simulated structural strength in the expansion direction; and the higher the average value, the smaller the expansion distance, and the lower the average value, the larger the expansion distance.

[0039] Other features and corresponding beneficial effects of the present invention are described in the latter part of the specification, and it should be understood that at least some of the beneficial effects become obvious from the description in the specification of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic flow chart of a topology optimization method for a main substrate of a lithography machine provided in this application;

[0041] Figure 2 This is a schematic structural diagram of a main substrate of a lithography machine provided in this application.

[0042] Description of reference numerals:

[0043] 1. Main substrate;

[0044] 11. The first non-design area; 12. The second non-design area. DETAILED DESCRIPTION

[0045] The following is an explanation of the embodiments of the present invention by specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this embodiment. On the contrary, the purpose of introducing the invention in conjunction with the embodiment is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will contain many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0046] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0047] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0048] In the description of the present invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first," "second," etc. may explicitly or implicitly include one or more of the features. In the description of the invention of this application, unless otherwise specified, "plurality" means two or more.

[0049] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0050] To make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0051] See also Figure 1 and Figure 2 , Figure 1 This is a flow chart of a topology optimization method for a main substrate of a lithography machine provided in this application. Figure 2 This is a schematic structural diagram of a main substrate of a lithography machine provided in this application.

[0052] like Figure 1 and Figure 2 As shown, an embodiment of the present application provides a topology optimization method for a main substrate of a lithography machine, comprising:

[0053] A topology optimization method for a main substrate 1 of a lithography machine includes: S1, constructing a simulation model of the main substrate 1;

[0054] S2. Set the design variables for topology optimization and determine the design area and non-design area;

[0055] S3. Define the optimization objective function, with the minimum flexibility and the maximum first-order modal frequency as the optimization goals;

[0056] S4. defining control variable parameters to control the checkerboard phenomenon;

[0057] S5. Optimize the design area.

[0058] Using this technical solution, minimizing flexibility and maximizing the first-order modal frequency are optimization goals. This allows the optimized main baseplate 1 to meet overall stiffness requirements while also minimizing its mass and manufacturing costs. Furthermore, maximizing the first-order modal frequency ensures that the dynamic characteristics of the main baseplate 1 meet design requirements.

[0059] In one embodiment, step S6 is further included, and step S6 includes:

[0060] Redesigning the main substrate 1 according to the topology optimization results;

[0061] The structural strength analysis of the redesigned main substrate 1 is performed to determine whether it meets the design requirements. If so, the topology optimization is completed; if not, the redesigned main substrate 1 is subjected to secondary optimization.

[0062] In one embodiment, the step of performing secondary optimization on the redesigned main substrate 1 includes:

[0063] The non-design area is expanded outward based on the original non-design area; wherein the expansion distance is determined based on the average value of the simulated structural strength in the expansion direction; and the higher the average value, the smaller the expansion distance, and the lower the average value, the larger the expansion distance.

[0064] In one embodiment, step S1 includes:

[0065] S11, establishing an initial structural model of the main substrate 1 in a three-dimensional software, and importing it into a simulation analysis software to perform mesh division, material property assignment, and preliminary mesh assembly to establish the finite element simulation model;

[0066] S12, determining multiple working conditions of the simulation model;

[0067] S13. Determine the corresponding model load condition and corresponding boundary conditions according to the working condition;

[0068] S14. According to the working conditions, static and modal calculations are performed on the simulation model to obtain stress distribution and modal frequency of the main substrate 1 under multiple working conditions.

[0069] By adopting the above technical solution and constructing a finite element simulation model, the design difficulty of the main substrate 1 structure can be reduced and the design efficiency of the main substrate 1 structure can be improved; and the model load conditions, corresponding boundary conditions, stress distribution of the main substrate 1 and modal frequency can be determined in combination with the actual operating conditions of the main substrate 1, thereby ensuring the feasibility and rationality of topology optimization.

[0070] The simulation analysis software is configured as the Optistruct platform. In other alternative implementations, the simulation analysis software may also be other software or platforms capable of performing topology optimization.

[0071] In one embodiment, step S2 includes:

[0072] S21, the simulation model adopts a symmetrical structure and is provided with a single one-dimensional symmetry constraint;

[0073] S22: setting the interface area of ​​the simulation model as a non-design area, and setting other areas of the simulation model as design areas.

[0074] By adopting the above technical solution, only the interface area can be set as the non-design area, thereby ensuring the maximization of the optimization space; and the simulation model adopts a symmetrical structure and is provided with a single one-dimensional symmetry constraint; thereby facilitating actual casting based on the optimized simulation model, thereby reducing the manufacturing cost of the main substrate 1.

[0075] In one embodiment, the main substrate 1 includes a main board and a plurality of support columns supporting the main board; the non-design area includes a first non-design area 11 and a second non-design area 12;

[0076] The center of the main board is provided with an objective lens through hole, and a plurality of circular objective lens interfaces surrounding the objective lens through hole;

[0077] The mainboard is also provided with a plurality of gantry interfaces arranged in a rectangular plane;

[0078] The annular area simultaneously covering the multiple objective lens interfaces is set as the first non-design area 11, and the gantry interface area is directly set as the second non-design area 12;

[0079] Other areas of the mainboard and the plurality of support columns are set as the designed areas.

[0080] It should be noted that due to the extremely high precision requirements in the field of photolithography technology, when designing the main substrate 1, it is necessary to ensure that the static deformation is controlled at the micron level; this requires the main substrate 1 to use materials with high strength, high rigidity and high vibration damping performance; however, such materials are often expensive, and the overall volume of the main substrate 1 is large. Therefore, if a solid structure is directly used without structural topology, although the main substrate 1 can achieve or meet its structural strength and high precision requirements, it will result in a larger mass and a huge amount of material required, resulting in extremely high manufacturing costs. At the same time, the high mass leads to poor flexibility of the main substrate 1, making it difficult to adapt to work scenarios that require changes or activities.

[0081] Therefore, on the one hand, it is necessary to ensure that the main substrate 1 can meet the structural strength requirements of the existing working conditions; on the other hand, it is necessary to reduce the mass of the main substrate 1 as much as possible, so as to improve the flexibility of the main substrate 1 and reduce its manufacturing cost.

[0082] Therefore, in one embodiment, step S3 includes:

[0083] S31. Taking minimum flexibility as the optimization goal and setting the upper limit of the material removal volume constraint ratio to 20%, a topology optimization model of the main substrate 1 with minimum flexibility as the optimization goal is established.

[0084] In one embodiment, step S4 includes:

[0085] S41: Perform maximum and minimum member control, set the minimum member control to 2-3 times the grid size, and the maximum member control to less than 6 times the grid size;

[0086] S42: Set the CHECKER parameter to control the checkerboard phenomenon. When the CHECKER parameter value is 0, it indicates that the checkerboard phenomenon is not controlled; when the CHECKER parameter value is 1, it indicates that the entire checkerboard is controlled;

[0087] S43: Set the discrete parameter DISCRETE, set the default value of the discrete parameter DISCRETE to 1, and the solid element to 3.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A topology optimization method for a main substrate of a lithography machine, characterized in that: include: S1, building a simulation model of the main substrate; S2. Set the design variables for topology optimization and determine the design area and non-design area; The step S2 comprises: S21, the simulation model adopts a symmetrical structure and is provided with a single one-dimensional symmetry constraint; S22, setting the interface area of ​​the simulation model as a non-design area, and setting other areas of the simulation model as design areas; The main substrate includes a main board and a plurality of support columns supporting the main board; the non-design area includes a first non-design area and a second non-design area; The center of the main board is provided with an objective lens through hole, and a plurality of circular objective lens interfaces surrounding the objective lens through hole; The mainboard is also provided with a plurality of gantry interfaces arranged in a rectangular plane; The annular area simultaneously covering the plurality of objective lens interfaces is set as the first non-design area, and the gantry interface area is directly set as the second non-design area; Setting other areas of the mainboard and the plurality of support columns as the designed areas; S3. Define the optimization objective function, with the minimum flexibility and the maximum first-order modal frequency as the optimization goals; S4. defining control variable parameters to control the checkerboard phenomenon; S5. Optimizing the design area; The method further includes step S6, wherein step S6 includes: Based on the topology optimization results, the main base plate is redesigned; Perform structural strength analysis on the redesigned main baseboard to determine whether it meets the design requirements. If so, topology optimization is completed; if not, perform secondary optimization on the redesigned main baseboard. The steps for secondary optimization of the redesigned main substrate include: The non-design area is expanded outward based on the original non-design area; wherein the expansion distance is determined based on the average value of the simulated structural strength in the expansion direction; and the higher the average value, the smaller the expansion distance, and the lower the average value, the larger the expansion distance.

2. A topology optimization method for a main substrate of a lithography machine according to claim 1, characterized in that: The step S1 comprises: S11, establishing an initial structural model of the main substrate in a three-dimensional software, and importing it into a simulation analysis software to perform mesh division, material property assignment, and preliminary mesh assembly to establish the finite element simulation model; S12, determining multiple working conditions of the simulation model; S13. Determine the corresponding model load condition and corresponding boundary conditions according to the working condition; S14. According to the working conditions, static and modal calculations are performed on the simulation model to obtain stress distribution and modal frequency of the main substrate under multiple working conditions.

3. The topology optimization method for a main substrate of a lithography machine according to claim 1, characterized in that: The step S3 comprises: S31. Taking minimum flexibility as the optimization goal and setting the upper limit of the material removal volume constraint ratio to 20%, a main substrate topology optimization model with minimum flexibility as the optimization goal is established.

4. The topology optimization method for a main substrate of a lithography machine according to claim 1, characterized in that: The step S4 comprises: S41: Perform maximum and minimum member control, set the minimum member control to 2-3 times the grid size, and the maximum member control to less than 6 times the grid size; S42: Setting the CHECKER parameter to control the checkerboard phenomenon. When the value of the CHECKER parameter is 0, it indicates that the checkerboard phenomenon is not controlled; when the value of the CHECKER parameter is 1, it indicates that all checkerboards are controlled. S43: Set the discrete parameter DISCRETE, set the default value of the discrete parameter DISCRETE to 1, and the solid element to 3.

5. The topology optimization method for a main substrate of a lithography machine according to claim 2, characterized in that: The simulation analysis software is set to the Optistruct platform.

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