Method and device for determining lithography parameter range, storage medium and computer device

Abstract

The application discloses a kind of photolithography parameter budget determination method, device, storage medium and computer equipment.Method includes: determining the parameter weight of the photolithography parameter corresponding to photolithography system, and exposure experiment is carried out based on experimental parameter to obtain experimental exposure result;Determine the parameter combination in photolithography parameter, and based on experimental parameter, experimental exposure result and parameter weight, determine the target weighted normalization sum of parameter combination relative to experimental parameter;For target weighted normalization sum and exposure result, establish analytical model, utilize target weighted normalization sum and exposure result to carry out model fitting to analytical model, obtain fitting model;The inverse function of fitting model is calculated, based on the preset exposure result range and the inverse function of fitting model, the value range of budget weighted normalization sum is calculated, and the value range is determined as the value range of the photolithography parameter of photolithography system.The above-mentioned method can improve the calculation precision of photolithography parameter budget range.

Description

Technical Field

[0001] This invention relates to the field of high-resolution imaging system budget decomposition technology, and in particular to a method, apparatus, storage medium, and computer device for determining the range of photolithography parameters. Background Technology

[0002] With the continuous development of photolithography technology, photolithography machines have gradually become important equipment in semiconductor production and manufacturing, and have been widely used in the manufacturing of large-scale integrated circuits. The photolithography process uses optical exposure to copy the pattern on a photomask into a photoresist coated on the surface of a silicon wafer. Subsequently, processes such as development and etching further transfer the pattern onto the silicon wafer. Therefore, the technological level of the photolithography system directly determines the feature size in integrated circuit devices, playing a crucial role in the manufacturing of large-scale integrated circuits.

[0003] As integrated circuit process nodes continue to shrink, the requirements for lithography imaging quality are also constantly increasing. For extreme ultraviolet (EUV) lithography systems, the wavelength, bandwidth, polarization, and energy stability of the light source; the uniformity, polar symmetry, and ellipticity of the illumination system's pupil; and the numerical aperture and stray light of the projection system all have a crucial impact on the exposure results. However, these parameters are not fixed and may fluctuate within a certain range due to limitations such as production capacity. Therefore, to meet the requirements of lithography exposure results, the variation range of these parameters needs to be limited to a certain range, i.e., lithography parameters need to be budgeted and decomposed. However, due to the large number of lithography parameters, and the fact that a change in one lithography parameter may affect the change in another, the limitation of the variation range of individual lithography parameters may be inaccurate. That is, there may be situations where all parameters are within the range of single-parameter variation, but the exposure results do not meet the process conditions under the combination of multiple variable parameters, leading to poor accuracy in calculating the budget range of lithography parameters. Summary of the Invention

[0004] In view of this, this application provides a method, apparatus, storage medium and computer equipment for determining photolithography parameter budget, the main purpose of which is to solve the technical problem of poor calculation accuracy of the photolithography parameter budget range.

[0005] According to a first aspect of the present invention, a method for determining a lithography parameter budget is provided, applied to a lithography system, the method comprising:

[0006] The parameter weights of the lithography parameters corresponding to the lithography system are determined, and an exposure experiment is conducted on the lithography system based on preset experimental parameters to obtain the experimental exposure results.

[0007] A parameter combination is selected from the lithography parameters, and the target weighted normalized sum of the parameter combination is determined based on the experimental parameters, the experimental exposure results, and the parameter weights.

[0008] An analytical model is established based on the target weighted normalized sum and the experimental exposure results. The analytical model is then fitted using the target weighted normalized sum and the experimental exposure results to obtain a fitted model.

[0009] The inverse function of the fitted model is calculated, and the range of values ​​for the budget weighted normalized sum is calculated based on the preset exposure result range and the inverse function of the fitted model. The budget range of the lithography parameters of the lithography system is then determined according to the range of values.

[0010] According to a second aspect of the present invention, an apparatus for determining photolithography parameter budget is provided, the apparatus comprising:

[0011] The weight determination module is used to determine the parameter weights of the lithography parameters corresponding to the lithography system, and to conduct an exposure experiment on the lithography system based on preset experimental parameters to obtain the experimental exposure results.

[0012] The correlation coefficient module is used to select parameter combinations from the lithography parameters and determine the target weighted normalized sum of the parameter combinations based on the experimental parameters, the experimental exposure results, and the parameter weights.

[0013] The model fitting module is used to establish an analytical model based on the target weighted normalized sum and the experimental exposure results, and to fit the analytical model using the target weighted normalized sum and the experimental exposure results to obtain a fitted model.

[0014] The budget determination module is used to calculate the inverse function of the fitted model, calculate the range of values ​​for the budget weighted normalized sum based on the preset exposure result range and the inverse function of the fitted model, and determine the budget range of the lithography parameters of the lithography system according to the range of values.

[0015] According to a third aspect of the present invention, a storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the above-described method for determining the lithography parameter budget.

[0016] According to a fourth aspect of the present invention, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described method for determining the lithography parameter budget.

[0017] This invention provides a method, apparatus, storage medium, and computer device for determining lithography parameter budgets. First, the parameter weights of each lithography parameter required to operate the lithography system are determined. Exposure experiments are conducted on the lithography system using experimental parameters including each lithography parameter, yielding exposure results for each experimental parameter. Then, multiple lithography parameters are selected from all lithography parameters to form parameter combinations. Using the values ​​of the experimental parameters, the exposure results obtained from experimental exposure based on the experimental parameters, and the parameter weights of each lithography parameter in the parameter combination, a target weighted normalized sum of the parameter combination is calculated. Further, an analytical model is established based on the target weighted normalized sum and the exposure results. The analytical model is then fitted using the target weighted normalized sum and the exposure results to obtain a fitted model. Finally, the inverse function of the fitted model is calculated. Based on a preset range of exposure results used to calibrate whether the exposure results are acceptable and the inverse function of the fitted model, the range of values ​​for the budget weighted normalized sum is calculated. The budget range of the lithography parameters of the lithography system is determined according to this range. The technical solution of this application can obtain a common budget of lithography parameters that meets the lithography process conditions by treating the budget of the lithography system as a common budget of multiple lithography parameters in the parameter combination. When performing subsequent lithography operations, it is only necessary to ensure the effectiveness of the exposure results by the weighted normalization of the lithography parameters and that they are within the budget range of the lithography parameters. This significantly improves the calculation accuracy of the budget range of lithography parameters.

[0018] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0020] Figure 1 A flowchart illustrating a method for determining photolithography parameter budget provided by an embodiment of the present invention is shown.

[0021] Figure 2 This diagram illustrates the structure of a device for determining photolithography parameter budgets according to an embodiment of the present invention.

[0022] Figure 3 A schematic diagram of another device for determining photolithography parameter budgets provided in an embodiment of the present invention is shown. Detailed Implementation

[0023] The present invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the present application can be combined with each other.

[0024] As integrated circuit process nodes continue to shrink, the requirements for photolithography imaging quality are also constantly increasing. For extreme ultraviolet (EUV) lithography systems, the wavelength, bandwidth, polarization, and energy stability of the light source; the uniformity, polar symmetry, and ellipticity of the illumination system's pupil; and the numerical aperture and stray light of the projection system all have a crucial impact on the exposure results. However, these parameters are not fixed and may fluctuate within a certain range due to limitations such as production capacity. Therefore, to meet the requirements for photolithography exposure results, the variation range of these parameters needs to be limited to a certain range, which necessitates the budget decomposition of photolithography parameters.

[0025] However, due to the large number of lithography parameters, and the fact that a change in one parameter can affect the change in another, it is not accurate enough to limit the range of variation for a single parameter. That is, there may be situations where all parameters are within the range of single-parameter variation, but the exposure results do not meet the process conditions under the combination of multiple parameter variations, leading to poor accuracy in calculating the budget range of lithography parameters.

[0026] To address the above problems, in one embodiment, such as Figure 1 As shown, a method for determining lithography parameter budget is provided and applied to a lithography system. Taking the application of this method to computer equipment as an example, the method includes the following steps:

[0027] 101. Determine the parameter weights of the lithography parameters corresponding to the lithography system, and conduct an exposure experiment on the lithography system based on the preset experimental parameters to obtain the experimental exposure results.

[0028] The lithography parameters are those that need to be set during the exposure operation of the lithography machine in the lithography system, including exposure metering, polarization, field of view position, numerical aperture, and stray light. Furthermore, each lithography parameter has a preset ideal value and a maximum value, where the maximum value can be 110% of the preset ideal value. Additionally, there can be multiple sets of experimental parameters, each containing all types of lithography parameters, and the value of each parameter can be predetermined. Specifically, the format of the experimental parameters can be as shown in Table 1.

[0029] Photolithography parameter 1 Photolithography parameter 2 Photolithography parameters 3 Photolithography parameter 4 …… 0.9 1.05 1.05 0.94 …… 1.1 0.9 0.9 0.94 …… 1.01 1.08 1.09 1.03 …… 0.96 0.94 0.92 0.98 ……

[0030] Table 1

[0031] In Table 1, each row can be a set of experimental parameters for conducting random experiments. An exposure experiment can be conducted using a set of experimental parameters to obtain the exposure result corresponding to that exposure experiment.

[0032] Furthermore, the parameter weight of each lithography parameter can be obtained in advance. By using the preset ideal value and maximum value of each lithography parameter, the lithography parameter for which the parameter weight needs to be calculated is set as the maximum value. Other lithography parameters besides this one are determined as preset ideal values ​​and exposure operations are performed. The size change of the exposure result and the size change of the ideal exposure size are calculated, as well as the numerical change of the lithography parameter set as the maximum value and its corresponding preset ideal value. The parameter weight of the lithography parameter is determined based on the ratio of the size change to the numerical change.

[0033] Specifically, the lithography system is exposed based on each set of experimental parameters to obtain the experimental exposure results corresponding to each set of experimental parameters.

[0034] 102. Select a parameter combination from the lithography parameters, and determine the target weighted normalized sum of the parameter combination based on the experimental parameters, the experimental exposure results, and the parameter weights.

[0035] Among the various lithography parameters, any number of lithography parameters can be selected to form a parameter combination. For example, if there are 5 lithography parameters, 1, 2, 3, 4, and 5 lithography parameters can be selected as parameter combinations, and the types of lithography parameters selected will be different between parameter combinations with the same lithography parameters.

[0036] Specifically, for each set of experimental parameters, the normalized value of each lithography parameter in the parameter combination can be calculated based on the numerical values ​​of the experimental parameters, the preset ideal values ​​of each lithography parameter, and the maximum value of each parameter. Furthermore, the weighted normalized sum of the parameter combination for each set of experimental parameters is calculated using the parameter weights and normalized values ​​of each lithography parameter. Further, the covariance between the weighted normalized sum and the experimental exposure results for each parameter combination can be calculated separately. The parameter combination with the largest covariance is determined, and this parameter combination is identified as the target parameter combination. The weighted normalized sum corresponding to this parameter combination is then identified as the target weighted normalized sum.

[0037] 103. Establish an analytical model based on the target weighted normalized sum and the experimental exposure results, and fit the analytical model using the target weighted normalized sum and the experimental exposure results to obtain a fitted model.

[0038] Specifically, modeling is performed using a combination of target parameters to obtain the target weighted normalized sum of the target parameter combinations obtained from random experiments. The value of the target weighted normalized sum is then used to fit the model with the value of the exposure result to determine the model coefficients and obtain the fitted model.

[0039] 104. Calculate the inverse function of the fitting model, calculate the range of values ​​for the budget weighted normalized sum based on the preset exposure result range and the inverse function of the fitting model, and determine the budget range of the lithography parameters of the lithography system according to the range of values.

[0040] The exposure result range refers to the size of the exposure result falling within the upper and lower limits of the process requirements. When the size of the exposure result falls within this range, the exposure result can be considered to meet the process requirements. Furthermore, the budget weighted normalized sum can be the weighted normalized sum of the parameter combination including lithography parameters. The value range of the budget weighted normalized sum can be the upper and lower limits of the weighted normalized sum of the parameter combination including lithography parameters. This value range can serve as a common budget for multiple lithography parameters in the parameter combination. When performing subsequent lithography production operations, as long as the weighted normalized sum of the parameter combination consisting of lithography parameters falls within this value range, the exposure operation result can be determined to meet the lithography process requirements.

[0041] Specifically, the inverse function of the fitted model can be calculated, and based on the upper and lower limits of the preset exposure result range, the upper and lower limits of the budget weighted normalized sum can be calculated in the inverse function of the fitted model, and the budget range of the lithography parameters of the lithography system can be determined according to the value range.

[0042] The method for determining the lithography parameter budget provided in this embodiment first determines the parameter weight of each lithography parameter required to run the lithography system, and conducts an exposure experiment on the lithography system using experimental parameters including each lithography parameter to obtain the exposure results for the experimental parameters. Then, multiple lithography parameters are selected from all lithography parameters to form a parameter combination, and the target weighted normalized sum of the parameter combination is calculated using the values ​​of the experimental parameters, the exposure results obtained from the experimental exposure based on the experimental parameters, and the parameter weight of each lithography parameter in the parameter combination. Further, an analytical model is established for the target weighted normalized sum and the exposure results, and the analytical model is fitted using the target weighted normalized sum and the exposure results to obtain a fitted model. Finally, the inverse function of the fitted model is calculated, and the range of values ​​for the budget weighted normalized sum is calculated based on a preset range of exposure results used to calibrate whether the exposure results are qualified and the inverse function of the fitted model. The budget range of the lithography parameters of the lithography system is determined according to the range of values. The technical solution of this application can obtain a common budget of lithography parameters that meets the lithography process conditions by treating the budget of the lithography system as a common budget of multiple lithography parameters in the parameter combination. When performing subsequent lithography operations, it is only necessary to ensure the effectiveness of the exposure results by the weighted normalization of the lithography parameters and that they are within the budget range of the lithography parameters. This significantly improves the calculation accuracy of the budget range of lithography parameters.

[0043] In one embodiment, the lithography parameters each correspond to a preset ideal value and a maximum value. The method for obtaining the parameter weights of the lithography parameters in step 101 includes: executing a loop until a preset condition is met, wherein the preset condition is that each lithography parameter obtains its corresponding parameter weight. The loop includes: first, selecting a variable parameter from all the lithography parameters, and determining the remaining lithography parameters (excluding the variable parameter) as ideal parameters. For example, if the lithography system has 5 lithography parameters, one lithography parameter can be selected as the variable parameter, and the remaining 4 lithography parameters can be determined as ideal parameters. Then, the maximum value of the lithography parameter corresponding to the variable parameter is determined as the value of the variable parameter, and an exposure operation is performed on the lithography system based on the variable parameter and each ideal parameter to obtain the exposure result. Specifically, the maximum value of the lithography parameter corresponding to the variable parameter can be used as the parameter value of the variable parameter. Further, an exposure operation is performed on the lithography system based on the variable parameter and each ideal parameter to obtain the exposure result.

[0044] Furthermore, the amount of exposure size change between the exposure result and the preset ideal exposure result is calculated, as well as the amount of parameter change between the parameter value of the variable parameter and the preset ideal value corresponding to the variable parameter. Based on the amount of exposure size change and the amount of parameter change, the parameter weight of the lithography parameter corresponding to the variable parameter is calculated. The ideal exposure result can be the optimal exposure size that can be obtained through the exposure operation, preset in advance. Specifically, the parameter weight of the lithography parameter can be calculated using Formula 1:

[0045]

[0046] Among them, w i ΔCD represents the parameter weights of the lithography parameters corresponding to the variable parameters. i Let ΔP be the change between the exposure result obtained by performing an exposure operation based on variable parameters and ideal parameters, and the ideal exposure result. i This refers to the change between the preset ideal value and the maximum value of the lithography parameter corresponding to the variable parameter. Finally, the preset ideal value corresponding to the variable parameter is determined as the parameter value of the variable parameter, and the variable parameter and the ideal parameter are determined as the lithography parameter. Specifically, the variable parameter and the ideal parameter are redefined as lithography parameters, and the parameter value of each lithography parameter is restored to its preset ideal value, so that the subsequent loop execution process can be executed normally. The embodiments provided in this application can efficiently determine the parameter weight of each lithography parameter, improving the efficiency of determining the lithography parameter budget.

[0047] In one embodiment, the number of parameter combinations can be multiple. The implementation method for determining the target weighted normalized sum of the parameter combinations based on the experimental parameters, the experimental exposure results, and the parameter weights in step 102 can be as follows: First, calculate the normalized sum of each lithography parameter in the parameter combination based on the parameter values ​​of the lithography parameters included in the experimental parameters, the preset ideal value corresponding to each lithography parameter in the parameter combination, and the maximum value corresponding to each lithography parameter. Specifically, for each set of experimental parameters, determine the parameter value of each lithography parameter included in that experimental parameter. The parameter values ​​corresponding to the lithography parameters included in the parameter combination can be obtained from the experimental parameters. For example, if the parameter combination includes a "polarization" lithography parameter, the parameter value corresponding to "polarization" in the experimental parameters can be determined as the parameter value corresponding to the "polarization" lithography parameter. If the parameter combination includes multiple lithography parameters, the parameter value of each lithography parameter can also be determined based on the above method. Furthermore, the preset ideal value and maximum value of each lithography parameter in the parameter combination can be determined separately, the first difference between the parameter value and the preset ideal value corresponding to the lithography parameter can be calculated, and the second difference between the maximum value of the lithography parameter and the parameter value can be calculated. The ratio of the first difference to the second difference is determined as the normalized sum of the lithography parameters.

[0048] Furthermore, the normalized sum of the lithography parameters can also be calculated using Formula 2:

[0049]

[0050] Among them, g i p is the normalized sum of the lithography parameters. max p0 represents the maximum value of the lithography parameter, p is the preset ideal value of the lithography parameter, and p is the maximum value of the lithography parameter. i This represents the parameter value corresponding to the lithography parameter in this set of experimental parameters. Furthermore, for a given set of experimental parameters, the normalized sum of each lithography parameter in the parameter combination under that set of experimental parameters can be calculated.

[0051] Then, based on the normalized sum of each lithography parameter in the parameter combination and the parameter weights, the weighted normalized sum of the parameter combination is calculated. Specifically, the weighted normalized sum of the parameter combination can be calculated based on Formula 3:

[0052]

[0053] Among them, h iThis is the weighted normalized sum of the parameter combination. Furthermore, based on the above method, the weighted normalized sum of the parameter combination relative to each group of experimental parameters can be calculated. If there are multiple types of parameter combinations, the weighted normalized sum of each parameter combination relative to each group of experimental parameters can be calculated separately using the above method.

[0054] Finally, based on the weighted normalized sum corresponding to each parameter combination and the experimental exposure result, the correlation coefficient between the weighted normalized sum corresponding to each parameter combination and the experimental exposure result is determined, and the weighted normalized sum corresponding to the largest correlation coefficient is determined as the target weighted normalized sum. The number of weighted normalized sums corresponding to each parameter combination is the same as the number of experimental parameter groups, and each weighted normalized sum corresponds to one experimental exposure result. Further, based on Formula 4, the correlation coefficient between the weighted normalized sum corresponding to each parameter combination and the experimental exposure result can be calculated respectively.

[0055]

[0056] Where r(h) i (,CD) represents the weighted normalized sum of this parameter combination and its correlation coefficient with the experimental exposure results, where cov(h) is the coefficient of variation. i ,CD) is the weighted normalized sum of the parameter combination and the covariance between it and the experimental exposure results, var[h i Let [D] represent the variance between the weighted normalized sums of the parameter combinations, and var[CD] represent the variance between the experimental exposure results corresponding to each group of experimental parameters. Further, based on the above method, the correlation coefficient between each parameter combination and the experimental exposure results can be calculated separately, and the correlation coefficient with the largest value can be determined. The weighted normalized sum corresponding to the largest correlation coefficient can then be determined as the target weighted normalized sum. The embodiments provided in this application can calculate the correlation parameters between each parameter combination and the experimental exposure results based on experimental parameters, experimental exposure results, and the weighted normalized sum of each parameter combination, and determine the weighted normalized sum corresponding to the optimal parameter combination, providing a foundation for subsequent model fitting work.

[0057] In one embodiment, the method for fitting the analytical model using the target weighted normalized sum and the experimental exposure results in step 103 to obtain the fitted model can be as follows: First, perform model fitting based on the experimental exposure results and the target weighted normalized sum, and calculate the model coefficients of the analytical model. Specifically, the model coefficients of the analytical model can be calculated based on Formula 5:

[0058]

[0059] Where CD(x) represents the experimental exposure result, x represents the target weighted normalized sum, and C represents the model coefficients. Then, based on the model coefficients, the experimental exposure result, and the target weighted normalized sum, the polynomial function of the analytical model is obtained, and this polynomial function is determined as the fitted model. As an example, the polynomial function can be in the form that the higher the power of the highest-order term, the more accurate the model. In reality, a power of less than or equal to 5 for the highest-order term is sufficient to meet the model's accuracy requirements. The embodiments provided in this application can perform modeling based on parameter combinations, along with the target weighted normalized sum of that parameter combination in a random experiment. The model is fitted using the target weighted normalized sum and the values ​​of the experimental exposure result to determine the model coefficients and obtain the fitted model.

[0060] In one embodiment, after calculating the inverse function of the fitted model, calculating the range of values ​​for the budget weighted normalized sum based on a preset exposure result range and the inverse function of the fitted model, and determining the budget range of the lithography parameters of the lithography system according to the value range, the method further includes: first, assigning parameter values ​​to the lithography parameters of the lithography system within the budget range. Specifically, assigning parameter values ​​whose weighted normalized values ​​are within the budget range to the lithography parameters. Then, performing a test exposure operation on the lithography system based on the lithography parameters to obtain the test exposure result of the test exposure operation. Specifically, performing an exposure operation on the lithography system based on the assigned lithography parameters to obtain the test exposure result of the exposure operation. Finally, determining whether the test exposure result is within a preset exposure size range; if the test exposure result is within the preset exposure size range, then determining that the budget range meets the accuracy requirements of the lithography system. The exposure size range is used to calibrate that when the test exposure result is within the exposure size range, the test exposure operation meets the exposure process requirements. Conversely, if the test exposure result is not within the preset exposure size range, it is determined that the lithography parameter budget does not meet the accuracy requirements of the lithography system, and a prompt message is issued to allow relevant personnel to take further action. The embodiments provided in this application can verify the budget range of lithography parameters, promptly identify budget ranges that do not meet requirements, and ensure the accuracy of exposure operations in subsequent exposure operations.

[0061] In one embodiment, the method for determining the target weighted normalized sum further includes: first, calculating the covariance between the weighted normalized sum corresponding to each parameter combination and the experimental exposure result; then, determining the parameter combination corresponding to the largest covariance and identifying the parameter combination as the target parameter combination; finally, identifying the weighted normalized sum corresponding to the target parameter combination as the target weighted normalized sum. The embodiments provided in this application can quickly determine the parameter combination most relevant to the experimental exposure result, identify the weighted normalized sum obtained from the parameter combination in a random experiment as the target weighted normalized sum, and perform model fitting based on the target weighted normalized sum, thereby improving the efficiency of determining the budget range of the etching parameters.

[0062] The method for determining lithography parameter budgets provided in this embodiment can obtain a common budget for lithography parameters that meets the lithography process conditions by treating the budget of the lithography system as a common budget of multiple lithography parameters in a parameter combination. This common budget is then verified to ensure that the lithography parameters determined based on the common budget meet the lithography process requirements. During subsequent lithography operations, only the weighted normalization of the lithography parameters and their inclusion within the budget range are needed to guarantee the validity of the exposure results, significantly improving the accuracy of calculating the lithography parameter budget range.

[0063] Furthermore, as Figure 1 The specific implementation of the method shown in this embodiment provides a device for determining the lithography parameter budget, such as... Figure 2 As shown, the device includes: a weight determination module 21, a correlation coefficient module 22, a model fitting module 23, and a budget determination module 24.

[0064] The weight determination module 21 can be used to determine the parameter weights of the lithography parameters corresponding to the lithography system, and to conduct an exposure experiment on the lithography system based on preset experimental parameters to obtain experimental exposure results.

[0065] The correlation coefficient module 22 can be used to select parameter combinations from the lithography parameters and determine the target weighted normalized sum of the parameter combinations based on the experimental parameters, the experimental exposure results, and the parameter weights.

[0066] The model fitting module 23 can be used to establish an analytical model for the target weighted normalized sum and the experimental exposure results, and to fit the analytical model using the target weighted normalized sum and the experimental exposure results to obtain a fitted model.

[0067] The budget determination module 24 can be used to calculate the inverse function of the fitted model, calculate the range of values ​​for the budget weighted normalized sum based on the preset exposure result range and the inverse function of the fitted model, and determine the budget range of the lithography parameters of the lithography system according to the range of values.

[0068] In specific application scenarios, the lithography parameters correspond to preset ideal values ​​and maximum values. The weight determination module 21 can be used to execute a loop process until a preset condition is met. The loop process includes: selecting a variable parameter from all the lithography parameters, and determining the remaining lithography parameters (excluding the variable parameter) as the ideal parameter; determining the maximum value of the lithography parameter corresponding to the variable parameter as the value of the variable parameter, and performing an exposure operation on the lithography system based on the variable parameter and each ideal parameter to obtain an exposure result; calculating the exposure size change between the exposure result and the preset ideal exposure result, and the parameter change between the value of the variable parameter and the preset ideal value corresponding to the variable parameter, and calculating the parameter weight of the lithography parameter corresponding to the variable parameter based on the exposure size change and the parameter change; determining the preset ideal value corresponding to the variable parameter as the parameter value of the variable parameter, and determining the variable parameter and the ideal parameter as the lithography parameter; the preset condition is that each lithography parameter obtains a corresponding parameter weight.

[0069] In specific application scenarios, the correlation coefficient module 22 can be used to calculate the normalized sum of each lithography parameter in the parameter combination based on the parameter values ​​of the lithography parameters included in the experimental parameters, the preset ideal value corresponding to each lithography parameter in the parameter combination, and the maximum value of each lithography parameter; calculate the weighted normalized sum of the parameter combination based on the normalized sum of each lithography parameter in the parameter combination and the parameter weight; determine the correlation coefficient between the weighted normalized sum of each parameter combination and the experimental exposure result based on the weighted normalized sum of each parameter combination and the experimental exposure result, and determine the weighted normalized sum corresponding to the largest correlation coefficient as the target weighted normalized sum.

[0070] In a specific application scenario, the correlation coefficient module 22 can be used to obtain the parameter values ​​corresponding to the lithography parameters included in the parameter combination in the experimental parameters; calculate the first difference between the parameter value and the preset ideal value corresponding to the lithography parameter, and calculate the second difference between the maximum value of the parameter corresponding to the lithography parameter and the parameter value; and determine the ratio of the first difference to the second difference as the normalized sum of the lithography parameters.

[0071] In specific application scenarios, the correlation coefficient module 22 can be used to calculate the covariance between the weighted normalized sum corresponding to each of the parameter combinations and the experimental exposure results; determine the parameter combination corresponding to the largest covariance, and determine the parameter combination as the target parameter combination; and determine the weighted normalized sum corresponding to the target parameter combination as the target weighted normalized sum.

[0072] In a specific application scenario, the model fitting module 23 can be used to perform model fitting based on the exposure result and the target weighted normalized sum, calculate the model coefficients of the analytical model; obtain the polynomial function of the analytical model based on the model coefficients, the exposure result and the target weighted normalized sum, and determine the polynomial function as the fitted model.

[0073] In specific application scenarios, such as Figure 3 As shown, the device also includes a result verification module 35, which is specifically used to allocate parameter values ​​for the lithography parameters of the lithography system within the budget range; perform a test exposure operation on the lithography system based on the lithography parameters to obtain the test exposure result of the test exposure operation; determine whether the test exposure result is within a preset exposure size range; if the test exposure result is within the preset exposure size range, then determine that the budget range meets the accuracy requirements of the lithography system.

[0074] It should be noted that other corresponding descriptions of the functional units involved in the photolithography parameter budget determination device provided in this embodiment can be found in [reference]. Figure 1 The corresponding descriptions in [the document] will not be repeated here.

[0075] Based on the above, Figure 1 Accordingly, this embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements the above-described method. Figure 1 The method for determining the lithography parameter budget is shown.

[0076] Based on this understanding, the technical solution of this application can be embodied in the form of a software product. The software product to be identified can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, or portable hard drive), including several instructions to cause a computer device (such as a personal computer, server, or network device) to execute the methods described in the various implementation scenarios of this application.

[0077] Based on the above, Figure 1 The method shown, and Figure 2 and Figure 3The illustrated embodiment of the apparatus for determining lithography parameter budgets, in order to achieve the above objectives, also provides a physical device for determining lithography parameter budgets. Specifically, this device can be a personal computer, server, smartphone, tablet computer, smartwatch, or other network device, etc. The physical device includes a storage medium and a processor; the storage medium is used to store a computer program; the processor is used to execute the computer program to achieve the above-described... Figure 1 The method shown.

[0078] Optionally, the physical device may also include a user interface, a network interface, a camera, radio frequency (RF) circuitry, sensors, audio circuitry, a Wi-Fi module, etc. The user interface may include a display screen, input units such as a keyboard, etc., and optional user interfaces may also include USB interfaces, card reader interfaces, etc. The network interface may optionally include standard wired interfaces, wireless interfaces (such as Wi-Fi interfaces), etc.

[0079] Those skilled in the art will understand that the physical device structure for determining photolithography parameter budget provided in this embodiment does not constitute a limitation on the physical device, and may include more or fewer components, or combine certain components, or have different component arrangements.

[0080] The storage medium may also include an operating system and a network communication module. The operating system is a program that manages the hardware and software resources of the aforementioned physical device, supporting the operation of information processing programs and other software and / or programs to be identified. The network communication module is used to enable communication between the various components within the storage medium, as well as communication with other hardware and software in the information processing physical device.

[0081] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms, or it can be implemented by hardware. By applying the technical solution of this application, firstly, the parameter weights of the lithography parameters corresponding to the lithography system are determined, and an exposure experiment is performed on the lithography system based on preset experimental parameters to obtain experimental exposure results; then, parameter combinations are selected from the lithography parameters, and the target weighted normalized sum of the parameter combinations is determined based on the experimental parameters, the experimental exposure results, and the parameter weights; next, an analytical model is established for the target weighted normalized sum and the exposure results, and the analytical model is fitted using the target weighted normalized sum and the exposure results to obtain a fitted model; finally, the inverse function of the fitted model is calculated, and the range of values ​​for the budget weighted normalized sum is calculated based on the preset range of exposure results and the inverse function of the fitted model, and the budget range of the lithography parameters of the lithography system is determined according to the range of values. Compared with the prior art, the calculation accuracy of the budget range of lithography parameters is significantly improved.

[0082] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of a preferred embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing this application. Those skilled in the art will understand that the modules in the apparatus of the embodiment can be distributed within the apparatus of the embodiment as described, or can be modified to be located in one or more apparatuses different from this embodiment. The modules of the above-described embodiment can be combined into one module, or further divided into multiple sub-modules.

[0083] The serial numbers in this application are for descriptive purposes only and do not represent the superiority or inferiority of any particular implementation scenario. The above disclosures are merely a few specific implementation scenarios of this application; however, this application is not limited thereto, and any variations conceived by those skilled in the art should fall within the protection scope of this application.

Claims

1. A method for determining photolithography parameter budget, applied to a photolithography system, characterized in that, The method includes: The parameter weights of the lithography parameters corresponding to the lithography system are determined, and an exposure experiment is conducted on the lithography system based on preset experimental parameters to obtain the experimental exposure results. A parameter combination is selected from the lithography parameters, and the target weighted normalized sum of the parameter combination is determined based on the experimental parameters, the experimental exposure results, and the parameter weights. An analytical model is established based on the target weighted normalized sum and the experimental exposure results. The analytical model is then fitted using the target weighted normalized sum and the experimental exposure results to obtain a fitted model. The inverse function of the fitted model is calculated, and the range of values ​​for the budget weighted normalized sum is calculated based on the preset exposure result range and the inverse function of the fitted model. The budget range of the lithography parameters of the lithography system is determined according to the range of values. The lithography parameters each correspond to a preset ideal value and a maximum value; the parameter weights of the lithography parameters are obtained through the following methods: The loop process is executed until a preset condition is met, wherein the loop process includes: Select one variable parameter from all the lithography parameters, and determine the remaining lithography parameters excluding the variable parameter as the ideal parameters. The maximum value of the lithography parameter corresponding to the variable parameter is determined as the parameter value of the variable parameter, and an exposure operation is performed on the lithography system based on the variable parameter and each ideal parameter to obtain the exposure result; Calculate the amount of exposure size change between the exposure result and the preset ideal exposure result, and the amount of parameter change between the parameter value of the variable parameter and the preset ideal value corresponding to the variable parameter; and calculate the parameter weight of the lithography parameter corresponding to the variable parameter based on the amount of exposure size change and the amount of parameter change. The preset ideal value corresponding to the variable parameter is determined as the parameter value of the variable parameter, and the variable parameter and the ideal parameter are determined as the lithography parameter; The preset condition is that each of the photolithography parameters obtains a corresponding parameter weight.

2. The method according to claim 1, characterized in that, The number of parameter combinations is multiple; determining the target weighted normalized sum of the parameter combinations based on the experimental parameters, the experimental exposure results, and the parameter weights includes: Based on the parameter values ​​of the lithography parameters included in the experimental parameters, the preset ideal value corresponding to each lithography parameter in the parameter combination, and the maximum value of each lithography parameter, calculate the normalized sum of each lithography parameter in the parameter combination; The weighted normalized sum of the parameter combination is calculated based on the normalized sum of each lithography parameter in the parameter combination and the parameter weight. Based on the weighted normalized sum corresponding to each of the parameter combinations and the experimental exposure results, the correlation coefficient between the weighted normalized sum corresponding to each of the parameter combinations and the experimental exposure results is determined, and the weighted normalized sum corresponding to the largest correlation coefficient is determined as the target weighted normalized sum.

3. The method according to claim 2, characterized in that, The step of calculating the normalized sum of each lithography parameter in the parameter combination based on the parameter values ​​of the lithography parameters included in the experimental parameters, the preset ideal value corresponding to each lithography parameter in the parameter combination, and the maximum value corresponding to each lithography parameter includes: Obtain the parameter values ​​corresponding to the lithography parameters included in the parameter combination from the experimental parameters; Calculate the first difference between the parameter value and the preset ideal value corresponding to the lithography parameter, and calculate the second difference between the maximum value of the parameter corresponding to the lithography parameter and the parameter value; The ratio of the first difference to the second difference is determined as the normalized sum of the lithography parameters.

4. The method according to claim 2, characterized in that, The method for determining the target weighted normalized sum also includes: Calculate the weighted normalized sum and covariance between each of the parameter combinations and the experimental exposure results; Determine the parameter combination corresponding to the largest covariance, and define the parameter combination as the target parameter combination; The weighted normalized sum corresponding to the combination of the target parameters is determined as the target weighted normalized sum.

5. The method according to any one of claims 1-4, characterized in that, The step of fitting the analytical model using the target weighted normalized sum and the experimental exposure results to obtain the fitted model includes: Based on the experimental exposure results and the target weighted normalization sum, the model coefficients of the analytical model are calculated by fitting the model. Based on the model coefficients, the experimental exposure results, and the target weighted normalized sum, the polynomial function of the analytical model is obtained, and the polynomial function is determined as the fitted model.

6. The method according to claim 1, characterized in that, The method further includes: The budget range is the value of the lithography parameter allocation for the lithography system. Based on the lithography parameters, a test exposure operation is performed on the lithography system to obtain the test exposure result of the test exposure operation; Determine whether the test exposure result is within the preset exposure size range. If the test exposure result is within the preset exposure size range, then determine that the budget range meets the accuracy requirements of the lithography system.

7. A device for determining photolithography parameter budgets, applied to a photolithography system, characterized in that, The device includes: A weight determination module is used to determine the parameter weights of the lithography parameters corresponding to the lithography system, and to conduct an exposure experiment on the lithography system based on preset experimental parameters to obtain experimental exposure results. The lithography parameters each correspond to a preset ideal value and a maximum value. The method for obtaining the parameter weights of the lithography parameters includes: executing a loop process until a preset condition is met, wherein the loop process includes: selecting a variable parameter from all the lithography parameters, and determining the remaining lithography parameters (excluding the variable parameter) as the ideal parameter; and determining the maximum value of the lithography parameter corresponding to the variable parameter as the parameter number of the variable parameter. The system performs an exposure operation on the lithography system based on the variable parameters and each ideal parameter to obtain an exposure result; it calculates the change in exposure size between the exposure result and the preset ideal exposure result, as well as the change in parameter value between the variable parameter and the preset ideal value corresponding to the variable parameter, and calculates the parameter weight of the lithography parameter corresponding to the variable parameter based on the change in exposure size and the change in parameter; it determines the preset ideal value corresponding to the variable parameter as the parameter value of the variable parameter, and determines the variable parameter and the ideal parameter as the lithography parameter; the preset condition is that each lithography parameter obtains a corresponding parameter weight; The correlation coefficient module is used to select parameter combinations from the lithography parameters and determine the target weighted normalized sum of the parameter combinations based on the experimental parameters, the experimental exposure results, and the parameter weights. The model fitting module is used to establish an analytical model based on the target weighted normalized sum and the experimental exposure results, and to fit the analytical model using the target weighted normalized sum and the experimental exposure results to obtain a fitted model. The budget determination module is used to calculate the inverse function of the fitted model, calculate the range of values ​​for the budget weighted normalized sum based on the preset exposure result range and the inverse function of the fitted model, and determine the budget range of the lithography parameters of the lithography system according to the range of values.

8. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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