An optimization screening method, device, equipment, storage medium and program product of overlay marks

Abstract

The present application relates to the field of photolithography, in particular to an optimization screening method of overlay marks, comprising the following steps: inputting mark parameters of multiple groups of overlay marks; selecting one or more simulation factors and adding as editable screening conditions, the simulation factors including one or more combinations of manufacturability information, matching information, detectability information and accuracy information; obtaining information of the selected simulation factors corresponding to each group of overlay marks based on the mark parameters through a pre-designed calculation model; comparing the corresponding simulation factor information of each group of overlay marks with a pre-set standard respectively, and obtaining and outputting the overlay marks matching the standard. The present application also provides a device, equipment, storage medium and program product. The optimization screening method of overlay marks provided by the present application solves the problem that the current screening method of overlay marks is not reasonable enough and is not practical enough in actual application.

Description

[Technical Field]

[0001] This invention relates to the field of photolithography, and particularly to an optimized screening method for overlay marks. [Background Technology]

[0002] With the development of the semiconductor industry, the requirements for integrated circuit manufacturing processes are becoming increasingly stringent. Among these requirements, measuring overlay error in integrated circuit manufacturing is a crucial indicator for judging the alignment quality of the photolithography process, assessing the rationality of the designed overlay marks, and screening out substandard overlay marks. Current methods for screening overlay marks are not sufficiently effective and are not practical in real-world applications. [Summary of the Invention]

[0003] To address the problem that current methods for screening overprinted marks are not reasonable enough and not practical in real-world applications, this invention provides an optimized screening method for overprinted marks.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an optimized screening method for overlay marks, comprising the following steps:

[0005] Input the marking parameters for multiple sets of overlay marks;

[0006] One or more simulation factors can be selected and added as editable filter conditions, wherein the simulation factors include one or more combinations of manufacturability information, matching information, detectability information and accuracy information;

[0007] Based on the marking parameters, the information of the selected simulation factor corresponding to each group of overlay markings is calculated by a preset calculation model;

[0008] The corresponding simulation factor information of each set of overlay marks is compared with a preset standard to obtain and output overlay marks that match the standard.

[0009] Preferably, the manufacturability information includes the normalized logarithmic slope and the process window.

[0010] Preferably, the parameters of the process window include exposure margin and depth of focus.

[0011] Preferably, the detectability information includes a normalized intensity coefficient and sensitivity.

[0012] Preferably, the accuracy information includes: the change in the normalized intensity coefficient, the influence of the overlay signal transformation on asymmetry, the root mean square of the overlay signal change, and the root mean square of the sensitivity value change.

[0013] Preferably, the matching information includes conversion information, incremental conversion information, key dimension deviation of the graphic, and the difference in aberration sensitivity corresponding to the key dimension of the matching graphic.

[0014] Preferably, the marking parameters include simulation parameters, structural parameters, and basic rule structures; the computational model includes a computational lithography model and a measurement computational model; the computational lithography model performs simulation calculations based on the simulation parameters, structural parameters, and basic rule structures to obtain the manufacturability information and the matching information; the measurement computational model performs measurement calculations based on the simulation parameters, structural parameters, and basic rule structures to obtain the detectability information and the accuracy information.

[0015] Preferably, before performing calculations based on the marked parameters using a preset calculation model, the method further includes the following step: selecting whether to add perturbations to the basic rule structure.

[0016] Preferably, obtaining the overlay mark matching the standard further includes the following steps:

[0017] The manufacturability information, matching information, detectability information, and accuracy information corresponding to a set of overlay marks are compared with the standard, respectively.

[0018] If the standard is matched, the overlay mark is output;

[0019] If the criteria are not met, proceed to the next group for filtering.

[0020] To solve the above-mentioned technical problems, the present invention provides another technical solution as follows: an apparatus for applying the above method, the apparatus comprising:

[0021] The system includes a marker parameter input module, a selection module for selecting simulation factors, a calculation module for calculation, an information comparison module for comparing the calculated information with preset standards, and a marker output module for outputting overlay markers that match the standards.

[0022] To solve the above-mentioned technical problems, the present invention provides another technical solution as follows: a computer device, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above-mentioned method.

[0023] To solve the above-mentioned technical problems, the present invention provides another technical solution as follows: a computer-readable storage medium storing computer program instructions thereon, wherein the computer program instructions, when executed by a processor, implement the steps of the above-mentioned method.

[0024] To solve the above-mentioned technical problems, the present invention provides another technical solution as follows: a computer program product, comprising a computer program or instructions, wherein the computer program or instructions, when executed by a processor, implement the steps of the above-mentioned method.

[0025] Compared with the prior art, the optimized screening method for overlay marks provided by the present invention has the following beneficial effects:

[0026] 1. By calculating and analyzing one or more of the manufacturability, matching, detectability, and accuracy information of the input multiple sets of overlay marking parameters, comparing them with preset standards, and adding editable filtering conditions to the simulation factors, the characteristics of the overlay markings can be simulated and analyzed in a targeted manner as needed. Overlay markings that meet the filtering criteria can be accurately selected, making it more practical and efficient in actual applications.

[0027] 2. Simulation analysis is performed on the normalized logarithmic slope and process window of the overlay marks. Based on the exposure energy (exposure margin) and depth of focus of the important dimensions of the pattern detected by the exposure results, manufacturability is simulated and analyzed. Refining the simulation process to these specific parameters allows for more accurate manufacturability analysis and improves the reliability of the manufacturability simulation results.

[0028] 3. The normalized intensity coefficient and sensitivity of the overprinted mark are simulated and analyzed, so that the detectionability simulation results are compared with the preset standard with the corresponding specific values, thereby obtaining the evaluation results and improving the reliability of the detectionability simulation results.

[0029] 4. The changes in the normalized intensity coefficient of the overlay mark, the influence of the overlay signal transformation on asymmetry, the root mean square of the overlay signal change, and the root mean square of the sensitivity value change are analyzed and compared. By fitting and analyzing the changes of different parameters within their preset standard range, the simulation results with comprehensive accuracy information are obtained, thus improving the accuracy of the simulation.

[0030] 5. Matching information includes conversion information, incremental conversion information, key dimension deviation of the graphic, and the difference in aberration sensitivity corresponding to the key dimension of the matching graphic. By comparing the above information with preset standards, the matching information between the overlay mark and the device during the manufacturing process can be obtained, making the simulation results more consistent with the actual manufacturing process and providing important reference for actual production and manufacturing.

[0031] 6. The marking parameters include simulation parameters, structural parameters, and basic rule structures. The calculation models include computational lithography models and measurement calculation models. The computational lithography model performs simulation calculations based on simulation parameters, structural parameters, and basic rule structures to obtain manufacturability and matching information. The measurement calculation model performs measurement calculations based on simulation parameters, structural parameters, and basic rule structures to obtain detectability and accuracy.

[0032] Simulation calculations were performed using both computational lithography and metrology models to obtain manufacturability, matching, detectability, and accuracy information of the input marker parameters. This made the evaluation process more reasonable and clear, and increased the rationality of the screening method.

[0033] 7. Before performing calculations based on the labeled parameters using a preset calculation model, the following steps are also included: selecting whether to add perturbations to the basic rule structure.

[0034] In actual photolithography and measurement processes, slight deviations often occur in the basic regular structure. Adding a selection perturbation process can optimize the simulation process and make the overlay marks selected by the simulation calculation more reasonable.

[0035] 8. The present invention also provides an apparatus for implementing the above method, which has the same beneficial effects as the above-described method for screening by overlay marking, and will not be described in detail here.

[0036] 9. The present invention also provides a computer device that has the same beneficial effects as the above-described method for screening by overlay marking, and will not be described in detail here.

[0037] 10. Embodiments of the present invention also provide a computer-readable storage medium, which has the same beneficial effects as the above-described method for screening by overlay marking, and will not be described in detail here.

[0038] 11. The present invention also provides a computer program product that has the same beneficial effects as the above-described method for screening by overlay marking, and will not be described in detail here. [Attached Image Description]

[0039] Figure 1 This is the flowchart of the overlay mark optimization and screening method provided in the first embodiment of the present invention. Figure 1 .

[0040] Figure 2 This is the simulation process for selecting simulation factors provided in the first embodiment of the present invention. Figure 1 .

[0041] Figure 3 This is a schematic diagram of projection lithography provided in the first embodiment of the present invention.

[0042] Figure 4 This is a schematic diagram of the optical measurement device provided in the first embodiment of the present invention.

[0043] Figure 5 This is a schematic diagram of the uDBO marking provided in the first embodiment of the present invention.

[0044] Figure 6 This is a schematic diagram of DBO marking based on the diffraction principle provided in the first embodiment of the present invention.

[0045] Figure 7 This is a schematic diagram of the marking and segmentation type provided in the first embodiment of the present invention.

[0046] Figure 8 This is a schematic diagram of the design layer structure for 1D grating overlay sidewall corner perturbation provided in the first embodiment of the present invention. Figure 1 .

[0047] Figure 9 This is a schematic diagram of the design layer structure for 1D grating overlay sidewall corner perturbation provided in the first embodiment of the present invention. Figure 2 .

[0048] Figure 10 This is a schematic diagram of the design of the sidewall angle of the bottom structure for 1D grating overlay sidewall corner perturbation provided in the first embodiment of the present invention.

[0049] Figure 11 This is a computational photolithography flowchart provided in the first embodiment of the present invention.

[0050] Figure 12 This is a measurement calculation flowchart provided in the first embodiment of the present invention.

[0051] Figure 13 This is the flow chart of the overlay mark screening method provided in the first embodiment of the present invention. Figure 2 .

[0052] Figure 14 This is a schematic diagram of the device structure provided in the second embodiment of the present invention.

[0053] Figure 15 This is a schematic diagram of the structure of a computer device provided in the third embodiment of the present invention.

[0054] Figure 16 This is a schematic diagram of the structure of a computer-readable storage medium provided in the fourth embodiment of the present invention.

[0055] Figure 17 This is a schematic diagram of the structure of the computer program product provided in the fifth embodiment of the present invention.

[0056] Explanation of reference numerals in the attached diagram:

[0057] 1. An optimized screening method for overlay marks; 2. An apparatus; 3. Computer equipment; 4. A computer-readable storage medium; 5. A computer program product;

[0058] 10. Marking parameters; 11. Computational model; 12. Manufacturability information; 13. Matching information; 14. Detectability information; 15. Accuracy information; 16. Measurement database; 17. System parameter database; 18. Overlay mark database; 19. Simulation factor; 20. Input module; 21. Calculation module; 22. Comparison module; 23. Output module; 30. Memory; 31. Processor; 40. Computer program instructions; 50. Computer program or instructions;

[0059] 100. Simulation parameters; 101. Structural parameters; 102. Basic regular structure; 110. Computational lithography model; 111. Measurement calculation model; 300. Computer program;

[0060] 1000. Material parameters; 1001. Aberrations; 1002. Measurement equipment system parameters; 1010. Overlay mark type; 1020. 3D film structure; 1100. Photolithography reference index; 1101. Laser source; 1102. Condenser lens; 1103. Mask; 1104. Projection lens; 1105. Silicon wafer; 1110. Measurement reference index; 1111. Light source; 1112. Filter assembly; 1113. Beam shaping assembly; 1114. Illumination aperture; 1115. Beam splitter; 1116. Overlay mark; 1117. Objective lens; 1118. First detector; 1119. Mirror; 11120. Second detector; 11121. Imaging magnification system assembly; 11122. Imaging filter assembly;

[0061] 10000, Photolithography wavelength material parameters; 10001, Visible light wavelength material parameters; 10010, Photolithography process aberrations; 10011, Measurement process aberrations; 11000, Normalized logarithmic slope; 11001, Process window; 11100, Target coefficient; 11101, Stack sensitivity.

Detailed Implementation Methods

[0062] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0063] Please see Figure 1 The first embodiment of the present invention provides an optimized screening method 1 for overlay marks, comprising the following steps:

[0064] Input the marking parameters for multiple sets of overlay marks;

[0065] One or more simulation factors 19 can be selected and added as editable filter conditions. The simulation factors 19 include one or more combinations of manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15.

[0066] Based on the marking parameters, the information of the selected simulation factor 19 corresponding to each set of overlay markings is calculated through a preset calculation model;

[0067] The corresponding simulation factor 19 information of each set of overlay marks is compared with the preset standard to obtain and output the overlay marks that match the standard.

[0068] By calculating and analyzing one or more of the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 of the input multiple sets of overlay marking parameters, comparing them with preset standards, and adding editable filtering conditions to the simulation factor 19, the characteristics of the overlay markings can be simulated and analyzed in a targeted manner as needed. Overlay markings that meet the filtering criteria can be accurately filtered out, making them more practical and efficient in actual applications.

[0069] Furthermore, manufacturability information 12 includes the normalized logarithmic slope NISL and the process window PW, which includes exposure margin EL and depth of focus DOF. Exposure margin EL refers to the maximum allowable deviation of exposure energy within the permissible range of linewidth variation. It is a fundamental parameter for measuring lithography processes. An optical exposure system can generate an exposure energy range that meets the design layout requirements, typically defined by the range of exposure energy selection where the change in CD value detected by exposure results is within + / -10%. Depth of focus DOF ​​is an important parameter for measuring the exposure process window PW, indicating the relationship between the image quality of the exposure system and the wafer surface position. Within the depth of focus range, the quality of the exposure image can be guaranteed. The depth of focus during exposure must be much greater than the unevenness of the wafer surface; only in this way can the yield of the lithography process be guaranteed.

[0070] Matching information 13 includes transformation information Shiftkpi:, incremental transformation information DeltaShiftkpi:, key dimension deviation MatchCD, and the difference in aberration sensitivity corresponding to the key dimension of the matched image (Mindeltashift). For the evaluation criteria of matching information, the smaller the difference between the transformation information, incremental transformation information, and the aberration sensitivity corresponding to the key dimension of the matched image, the better.

[0071] Detectability information 14 includes the normalized intensity coefficient TC and the sensitivity SS. For evaluating detectability information, a larger normalized intensity coefficient TC is better, and a smaller sensitivity SS is better.

[0072] Accuracy information 15 includes the change in the normalized intensity coefficient, the impact of the overlay signal transformation on asymmetry, the root mean square of the overlay signal change, and the root mean square of the sensitivity value change. For the evaluation criteria of accuracy information, the smaller the change in the normalized intensity coefficient and the smaller the impact of the overlay signal transformation on asymmetry, the better.

[0073] Please see Figure 2 For example, manufacturability information 12 and detectability information 14 are selected as simulation factors 19, and manufacturability screening conditions and detectability screening conditions are added accordingly for simulation screening.

[0074] Understandably, the screening criteria for detectability information 12 are the normalized intensity coefficient TC and sensitivity SS; the screening criteria for manufacturability information 14 are the normalized logarithmic slope NISL and process window PW.

[0075] After incorporating manufacturability screening conditions into the simulation, a manufacturability result output table is obtained. The screened overlay marks are then passed to the next step for detectability simulation screening. Based on the detectability screening conditions, a detectability result output table is obtained, along with the corresponding overlay marks after secondary screening. It should be noted that the manufacturability and detectability result output tables are output because simulation factor 19 represents manufacturability information 12 and detectability information 14. If simulation factor 19 represents accuracy information 15 and matching information 13, then accuracy and matching result output tables would be output accordingly. Simulation factor 19 is selectable and editable, therefore, different result output tables may be generated for each simulation.

[0076] Understandably, when selecting simulation factor 19, manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 can also be selected simultaneously for simulation. Correspondingly, after each simulation step, manufacturability result output table, matching result output table, detectability result output table, and accuracy result output table are output.

[0077] Furthermore, the marking parameters 10 include simulation parameters 100, structural parameters 101, and basic rule structure 102. The calculation model 11 includes a computational lithography model 110 and a measurement calculation model 11. The computational lithography model 110 performs computational lithography process simulation calculations based on the simulation parameters 100, structural parameters 101, and basic rule structure 102 to obtain manufacturability information 12 and matching information 13. The measurement calculation model 11 performs measurement calculation process simulation calculations based on the simulated parameters 100, structural parameters 101, and basic rule structure 102 to obtain detectability information 12 and accuracy information 13.

[0078] Specifically, simulation parameters 100 include material parameters 1000 involved in the simulation or material parameters 1000 already existing in the material library. Material parameters 1000 are divided into lithography wavelength material parameters 10000 required at a 193nm lithography wavelength and visible light wavelength material parameters 10001. Material properties affect the electromagnetic wave reflection and projection characteristics in lithography and measurement calculations. Therefore, for different wavelengths and frequencies of light at the lithography wavelength and visible light in the measurement process, users need to input different material properties or load different material properties from the material library. For example, silicon has a refractive index n1 = 4.0817 and an attenuation coefficient k1 of 0.040882 at a visible light wavelength of 550nm, but at a wavelength of 193nm, silicon has a refractive index n2 = 0.883 and an attenuation coefficient k2 = 2.788.

[0079] Understandably, simulation parameter 100 also includes aberration 1001. Aberration 1001 includes aberration 10010 in the photolithography process and aberration 10011 in the measurement calculation process.

[0080] Please see Figure 3 The laser light source 1101 illuminates the mask 1103 through the focusing lens 1102, and the pattern on the mask 1103 is transferred to the surface of the silicon wafer 1105 through the projection lens 1104. Due to the characteristics of projection lithography, aberration 1001 will inevitably be introduced, so aberration 1001 needs to be introduced during the overlay marking and screening process.

[0081] Please see Figure 4 The overlay marks used in the photolithography process are detected by an optical measurement system containing an objective lens 1117. Therefore, the aberration 1001 introduced by the objective lens 1117 also needs to be considered in the overlay mark selection method.

[0082] Furthermore, based on the marking parameters 10, through a preset calculation model 11, namely the computational lithography model 110 and the measurement calculation model 11, one or more of the following information corresponding to each set of overlay markings—manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15—are obtained. Simulation calculations are performed using the computational lithography model 110 and the measurement calculation model 11 respectively to obtain the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 of the input marking parameters 10. This makes the evaluation process more reasonable and clear, increasing the rationality of the selection method.

[0083] Among them, the simulation parameters 100 in the marking parameters 10 also include the measurement equipment system parameters 1002. The optical measurement parameters of the actual measurement equipment are used as inputs for the simulation parameters 100. The detectability information 14 and accuracy information 15 of the input overlay mark are calculated by the measurement calculation model 11.

[0084] Please see Figure 4 For example, light emitted from light source 1111 passes through light filtering assembly 1112, beam shaping assembly 1113, and illumination aperture 1114, and is then projected onto the marking X-mark 1116 via beam splitter 1115. The signal diffracted by marking X-mark 1116 is collected by objective lens 1117; one signal is collected by first detector 1118, and the other signal is collected by second detector 11120 after passing through mirror 1119. The signal from second detector 11120 is processed by imaging amplification system assembly 11121 and imaging filtering assembly 11122. Specifically, the measurement equipment system parameters 1002 include: spectral information of the input device, measurement illumination mode, size of the detection objective lens, frequency domain filter value, and aperture size, etc. The spectral information needs to be determined based on the... Figure 4 The light source 1111 in the measurement is used for measurement, and the result is used as input for the measurement model calculation. The measurement illumination mode specifically refers to the different illumination modes that can be selected in the overlay equipment for different processes to facilitate the measurement of actual production indicators (such as measurement repeatability). Common illumination modes in the industry include quadrupole illumination for DBO and bipolar illumination for u-DBO. The probe objective refers to... Figure 4 The numerical aperture of the objective lens 1117 in the measurement system determines the spatial range for collecting overlay signals during measurement. The numerical aperture size of the frequency domain filter refers to the aperture stop size designed before imaging to filter out 0th-order light for the u-DBO diffraction signal.

[0085] The structural parameter 101 includes the type of overlay mark. The type of overlay mark can be imported from the database, or different common overlay mark types 1010 can be defined. At the same time, you can also choose whether to split the mark type.

[0086] For example, please refer to Figures 5 to 7 To accommodate different mark size requirements, after inputting structural parameter 101, the mark can be segmented. For an example, please refer to [link to example]. Figure 7 The segmentation types include BasicLS, ParalST_P(N), VertST_P(N), and 2DST_P(N).

[0087] Furthermore, after calculating one or more of the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 corresponding to each set of overlay marks, it is compared with a preset standard to obtain and output the overlay marks that match the standard, thus completing the screening of overlay marks.

[0088] Understandably, one or more of the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 are determined by the selected simulation factor 19.

[0089] By calculating and analyzing one or more of the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 of the marking parameters 10 of multiple sets of overprinted marks, and comparing them with preset standards, qualified overprinted marks can be accurately and comprehensively screened out. This method is easy to implement and more practical in real-world applications.

[0090] Preferably, after inputting the label parameter 10 and before performing calculations based on the label parameter 10 using a preset calculation model, the method further includes the following step: selecting whether to add perturbations to the basic rule structure 102.

[0091] The basic rule structure 102 includes the 3D membrane structure 1020 after all processes are completed. Based on the 3D membrane structure 1020, it is selected whether to set perturbations.

[0092] For example, please refer to Figure 8 Each layer can be freely customized with added materials and structures. Overlay design only requires designing periodic structured gratings in the upper and lower volumes, and then designing perturbations on the basic structure. For example, such as... Figures 9 to 10 This involves designing the sidewall angles of the underlying structure. Common structural perturbations include changes in the sidewall angles and bottom tilt. In actual photolithography and measurement processes, the basic regular structure 102 often exhibits slight deviations. Incorporating a perturbation selection process can optimize the simulation process and make the overlay marks selected in the simulation calculation more reasonable.

[0093] Furthermore, simulations are performed based on the computational lithography model 110 and the measurement calculation model 11. The computational lithography model 110 is used to calculate and evaluate the manufacturability and matching of the overlay mark; the measurement calculation model 11 is used to calculate and simulate the detectability and accuracy of the designed overlay mark.

[0094] Specifically, the computational lithography model 110 performs simulation calculations based on simulation parameters 100, structural parameters 101, and basic regular structure 102 to obtain manufacturability information 12 and matching information 13, further including the following steps:

[0095] The computational lithography model 110 performs simulation calculations based on the simulated parameters 100, structural parameters 101, and basic rule structure 102 to simulate the lithography process and obtain the lithography reference index 1100 corresponding to manufacturability and compatibility.

[0096] The lithography reference index 1100 is compared with the preset lithography database to obtain manufacturability information 12 and matching information 13.

[0097] For example, please refer to Figure 11The algorithm inputs the material parameters 1000, lithography process aberrations 10010, and overlay mark type 1010 for a 193nm film system. It also inputs the basic rule structure 102 after all overlay mark processes to select whether to set perturbations. If perturbations are set, the input is based on the perturbation structure; otherwise, it is based on the basic rule structure 102. The input values ​​are then introduced into the computational lithography model 110 to calculate the lithography reference index 1100. The lithography reference index 1100 includes the normalized logarithmic slope 11000 and the process window 11001. The normalized logarithmic slope 11000 and the process window 11001 are compared with a preset database to evaluate the manufacturability and matching of the overlay marks. Different mark parameters 10 correspond to different lithography reference indices 1100. By comparing the calculated lithography reference index 1100 with the corresponding database, overlay marks that meet the manufacturability and matching standards can be obtained, further optimizing the selection results.

[0098] Specifically, the measurement calculation model 11 performs measurement calculations based on simulation parameters 100, structural parameters 101, and basic rule structure 102 to obtain detectability information 14 and accuracy information 15, and further includes the following steps:

[0099] The measurement calculation model 11 simulates the measurement process based on the simulation parameters 100, structural parameters 101 and basic rule structure 102 to perform measurement calculations and obtain the measurement reference index 1110 corresponding to detectability and accuracy.

[0100] The measurement reference index 1110 is compared with the preset measurement database 16 to obtain detectability information 14 and accuracy information 15.

[0101] For example, please refer to Figure 12 The system inputs the material parameters 1000 of the visible light film system, the measurement equipment system parameters 1002, the measurement process aberrations 10011, and the overlay mark type 1010. It also inputs the basic rule structure 102 after all overlay mark processes to select whether to set perturbations. If perturbations are set, the input is based on the perturbation structure; otherwise, it is based on the basic rule structure 102. The input values ​​are then introduced into the measurement calculation model 11 for measurement calculation, yielding the measurement reference index 1110 corresponding to detectability and accuracy. The measurement reference index 1110 includes the target coefficient 11100 and the stack sensitivity 11101. The target coefficient 11100 and the stack sensitivity 11101 are compared with the preset measurement database 16 to obtain detectability information 14 and accuracy information 15. Different marking parameters 10 correspond to different measurement reference indices 1110. By comparing the calculated measurement reference indices 1110 with the corresponding measurement database 16, overlay markings that meet the detectability information 14 and accuracy standards can be obtained, thus optimizing the screening results.

[0102] Furthermore, obtaining the matching standard overlay marks further includes the following steps:

[0103] The manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 corresponding to a set of overlay marks are compared with the standard respectively;

[0104] If the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 corresponding to the overlay mark match the standard, then the overlay mark is output.

[0105] If the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 corresponding to the overlay mark do not match the standard, then the manufacturability information 12, matching information 13, detectability information 14, and accuracy information 15 corresponding to the next set of overlay marks will be compared with the standard respectively.

[0106] Preferably, the method further includes the following steps:

[0107] The measurement reference index 1110 is compared with the preset system parameter database 17 to obtain the corresponding reference simulation parameter 100, which is used to guide the metrological optical hardware configuration of the measurement equipment, such as wavelength and illumination mode. During the measurement calculation process, the obtained measurement reference index 1110 is compared with the preset measurement database 16 to output the corresponding reference simulation parameter 100. In practical applications, for each set of marked parameters 10, the system parameters can be adjusted specifically according to the simulation parameter 100, such as the spectral information of the input device, the measurement illumination mode, the size of the detection objective lens, and the numerical aperture size of the frequency domain filter, making the measurement process more targeted and the measurement results more accurate.

[0108] Preferably, after outputting the overlay marks that match the standard, the method further includes the following steps:

[0109] The obtained matching standard overlay marks are saved to the overlay mark database 18, which can serve as reference and empirical data for subsequent simulations. By storing the matching standard overlay marks in the overlay mark database 18, when the same or similar data is input next time, simulation steps can be reduced, simulation time can be saved, and even the corresponding simulation results can be directly output.

[0110] Preferably, after outputting the overlay marks that match the standard, the method further includes the following steps:

[0111] Based on the output, choose whether to adjust the simulation parameters by 100% and re-perform the simulation screening.

[0112] Please see Figure 13For example, this embodiment optimizes and filters the entire process as shown in the diagram. First, the overlay mark type 1010 is input for design, the simulation factor 19 is selected, the material parameters required for simulation 1000 are selected, the aberrations required for simulation 1001 are selected, the measurement equipment system parameters 1002 are selected, and the basic rule structure 102 after all the overlay mark processes is selected. Then, based on the basic rule structure 102, it is selected whether to set perturbation. If perturbation is set, it is input with perturbation structure. If perturbation is not set, it is input with basic rule structure. The computational model 11 and parameters are loaded for simulation calculation. The computational lithography model 110 performs simulation calculation to evaluate and analyze manufacturability and matching, while the measurement computational model 11 evaluates and analyzes detectability and accuracy. The obtained manufacturability, matching, detectability, and accuracy analysis results are compared and evaluated with preset standards to obtain the overlay marks of the matching standards. Then, it is determined whether the output results meet the requirements. If not, the simulation parameters 100 are adjusted, the computational model 11 is loaded, and the simulation calculation is performed again. If the requirements are met, the overlay marks of the matching standards and the reference simulation parameters 100 of the optical system of the measurement equipment are output, and the obtained overlay marks of the matching standards are saved to the overlay mark database 18.

[0113] The second embodiment of the present invention also provides a device 2 for implementing the above-described method 1. Please refer to [link / reference]. Figure 14 The device 2 includes a parameter input module 20 for input, a calculation module 21 for calculation, an information comparison module 22 for comparing the calculated information with a preset standard, a mark output module 23 for outputting overlay marks matching the standard, and an editing module 24 for editing and selecting simulation factors.

[0114] The third embodiment of the present invention also provides a computer device 3, please refer to [link / reference]. Figure 15 It includes a memory 30, a processor 31, and a computer program 300 stored on the memory 30. The processor 31 executes the computer program 300 to implement the steps of method 1.

[0115] The fourth embodiment of the present invention also provides a computer-readable storage medium 4, see below. Figure 16 It stores computer program instructions 40, which, when executed by the processor, implement the steps of method 1 described above.

[0116] The fifth embodiment of the present invention provides a computer program product 5, please refer to [link / reference]. Figure 17 This includes a computer program or instruction 50, which, when executed by a processor, implements the steps of method 1 described above.

[0117] In the embodiments provided by this invention, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B solely based on A; B can also be determined based on A and / or other information.

[0118] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Those skilled in the art should also recognize that the embodiments described in the specification are optional embodiments, and the actions and modules involved are not necessarily essential to the invention.

[0119] In various embodiments of the present invention, it should be understood that the sequence number of each process does not necessarily imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0120] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It is particularly important to note that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0121] The above provides a detailed description of an optimized screening method for overlay marks disclosed in the embodiments of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention. Any modifications, equivalent substitutions, and improvements made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An optimized screening method for overlay marks, used to simulate overlay errors, characterized in that: Includes the following steps: Input the marking parameters for multiple sets of overlay marks; One or more simulation factors can be selected and added as editable filter conditions, wherein the simulation factors include one or more combinations of manufacturability information, matching information, detectability information and accuracy information; Based on the marking parameters, the information of the selected simulation factor corresponding to each group of overlay markings is calculated by a preset calculation model; The corresponding simulation factor information of each group of overlay marks is compared with a preset standard to obtain and output overlay marks that match the standard. The accuracy information includes: the change in the normalized intensity coefficient, the influence of the overlay signal transformation on asymmetry, the root mean square of the overlay signal change, and the root mean square of the sensitivity value change. After outputting the overlay marks that match the standard, the following steps are also included: determining whether the output result meets the requirements, wherein the output result is the overlay marks that match the standard and the reference simulation parameters of the optical system of the measurement equipment; if it does not meet the requirements, adjusting the simulation parameters, loading the calculation model and re-performing the simulation calculation; if it meets the requirements, outputting the overlay marks that match the standard and the reference simulation parameters of the optical system of the measurement equipment. The marking parameters include simulation parameters, structural parameters, and basic rule structures. The computational model includes a computational lithography model and a measurement computational model. The computational lithography model performs simulation calculations based on the simulation parameters, structural parameters, and basic rule structures to obtain the manufacturability information and the matching information. The measurement computational model performs measurement calculations based on the simulation parameters, structural parameters, and basic rule structures to obtain the detectability information and the accuracy information.

2. The method as described in claim 1, characterized in that: The manufacturability information includes the normalized logarithmic slope and the process window.

3. The method as described in claim 2, characterized in that: The parameters of the process window include exposure margin and depth of focus.

4. The method as described in claim 1, characterized in that: The detectability information includes the normalized intensity coefficient and sensitivity.

5. The method as described in claim 1, characterized in that: The matching information includes transformation information, incremental transformation information, key dimension deviation of the graphic, and the difference in aberration sensitivity corresponding to the key dimension of the matching graphic.

6. The method as described in claim 1, characterized in that: Before performing calculations based on the labeled parameters using a preset calculation model, the following steps are also included: selecting whether to add perturbations to the basic rule structure.

7. The method as described in claim 1, characterized in that: Obtaining overlay marks that match the standard further includes the following steps: The manufacturability information, matching information, detectability information, and accuracy information corresponding to a set of overlay marks are compared with the standard, respectively. If the standard is matched, the overlay mark is output; If the criteria are not met, proceed to the next group for filtering.

8. An apparatus for applying the method as described in any one of claims 1-7, characterized in that: The device includes: The system includes a marker parameter input module, a selection module for selecting simulation factors, a calculation module for calculation, an information comparison module for comparing the calculated information with preset standards, and a marker output module for outputting overlay markers that match the standards.

9. A computer device, characterized in that: It includes a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method as described in claim 1.

10. A computer-readable storage medium having computer program instructions stored thereon, characterized in that: When the computer program instructions are executed by the processor, they implement the steps of the method as described in claim 1.

11. A computer program product, characterized in that: It includes a computer program or instructions that, when executed by a processor, implement the steps of the method of claim 1.

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