Method for analyzing vibration performance of worktable of photoetching machine and imaging quality

Abstract

This invention provides a method for analyzing the vibration performance and imaging quality of a lithography machine stage. By forming a feature test pattern related to the extreme motion and resolution of the lithography machine on a designed test mask, lithography and development imaging are performed. Combined with the established relationship model, the vibration performance of the lithography machine stage and the extreme imaging capability of the lithography machine under analysis are quantitatively fed back, providing quantitative analysis indicators for the stable operation and mass production quality of different lithography machines.

Description

Technical Field

[0001] This invention relates to the field of lithography machine performance analysis technology, and more specifically, to a method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage. Background Technology

[0002] Currently, the imaging quality of commonly used deep ultraviolet lithography machines and extreme ultraviolet lithography machines is strongly affected by the vibration performance of the workpiece stage, even when other parameters are stable.

[0003] refer to Figure 1 , Figure 1 This is a schematic diagram illustrating the exposure principle of a projection lithography machine, as shown below. Figure 1 The projection lithography machine shown adopts a projection exposure method. During the exposure process of the lithography machine, the mask stage and the wafer stage need to move synchronously at high speed according to a specific relationship. The exposure process is carried out by scanning and stepping, that is, many exposure areas are divided on the wafer, and the exposure process in each exposure area is completed by scanning.

[0004] The movement of the mask stage and wafer stage during the scanning process can be divided into four stages: 1. Acceleration stage, where the speed V increases during the time interval t0-t1; 2. Stabilization stage, where the speed V stabilizes at a fixed value during the time interval t1-t2; 3. Uniform exposure stage or imaging stage, where the speed V remains at the fixed value during the time interval t2-t3; 4. Deceleration stage, where the speed V decreases during the time interval t3-t4. After a certain exposure area is exposed, the mask stage and wafer stage move to the next exposure area by stepping to continue the scanning process, repeating the cycle to complete the exposure of the entire wafer.

[0005] However, during the uniform exposure stage, it is often difficult to maintain the speed synchronization of the mask stage and the wafer stage with nanometer-level precision, or there may be superimposed fine movements. Due to the constraints on the stability and consistency of the mask stage and the wafer stage under high-speed movement, actual lithography machines, especially new lithography machines that have not yet been put into use or newly developed lithography machines, often encounter situations where the vibration performance of the mask stage and the wafer stage is different at different movement speeds, and the vibration properties change at different running times, which seriously affects their imaging quality.

[0006] Therefore, how to analyze the vibration performance and imaging quality of the lithography machine workpiece stage is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, to solve the above problems, the present invention provides a method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the technical solution of which is as follows:

[0008] A method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the method comprising:

[0009] Design a test mask, wherein the test mask has a characteristic test pattern;

[0010] Based on the target lithography machine and the test mask, exposure imaging is performed at a preset lithography technology node to obtain target imaging parameters; wherein the vibration performance parameters of the target lithography machine at the preset lithography technology node meet the target requirements.

[0011] A relationship model is established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters;

[0012] Based on the test mask and the lithography machine to be analyzed, exposure imaging is performed at the preset lithography technology node to obtain the imaging parameters to be analyzed.

[0013] Based on the imaging parameters to be analyzed and the relationship model, the vibration performance parameters of the lithography machine to be analyzed are obtained.

[0014] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the design of the test mask, wherein the test mask has a characteristic test pattern, including:

[0015] Obtain the limit resolution of the lithography machine to be analyzed at the preset lithography technology node;

[0016] Based on the preset lithography technology node and the limit resolution, the minimum feature parameters of the feature test pattern are determined;

[0017] The feature test pattern is designed based on the minimum feature parameter to form a test mask with the feature test pattern.

[0018] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the feature test pattern includes multiple light-shielding strips arranged at intervals along a first direction.

[0019] The light-shielding strip extends along a second direction, and the first direction is perpendicular to the second direction;

[0020] The minimum characteristic parameter is the width of the light-shielding strip in the first direction.

[0021] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the feature test pattern includes multiple first light-shielding strips arranged at intervals along a third direction, and multiple second light-shielding strips arranged at intervals along the third direction.

[0022] Both the first light-shielding strip and the second light-shielding strip extend along the fourth direction, and the third direction is perpendicular to the fourth direction;

[0023] In the fourth direction, the first light-shielding strip and the second light-shielding strip are arranged at intervals;

[0024] The minimum characteristic parameter is the interval between the first light-shielding strip and the second light-shielding strip in the fourth direction.

[0025] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the feature test pattern includes multiple third light-shielding strips and a fourth light-shielding strip arranged sequentially at intervals along the fifth direction.

[0026] The third light-shielding strip extends along the sixth direction, and the fifth direction is perpendicular to the sixth direction;

[0027] The fourth light-shielding strip extends along the fifth direction, and in the sixth direction, the fourth light-shielding strip is located on one side of the third light-shielding strip;

[0028] The minimum characteristic parameter is the interval between the third and fourth light-shielding strips in the sixth direction.

[0029] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the target imaging parameters include the line parameters in the imaging results;

[0030] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0031] Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line parameters in multiple different imaging results;

[0032] By analyzing the line parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between line parameters and vibration performance is established.

[0033] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the target imaging parameters include the line edge roughness parameters in the imaging results.

[0034] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0035] Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line edge roughness parameters in multiple different imaging results;

[0036] By analyzing the line edge roughness parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the line edge roughness parameters and vibration performance is established.

[0037] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the target imaging parameters include the process window parameters in the imaging results;

[0038] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0039] Under the preset lithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain process window parameters in multiple different imaging results;

[0040] By analyzing the process window parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the process window parameters and vibration performance is established.

[0041] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the target imaging parameters include the line uniformity parameter in the imaging results.

[0042] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0043] Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line uniformity parameters in multiple different imaging results;

[0044] By analyzing the line uniformity parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the line uniformity parameters and vibration performance is established.

[0045] Preferably, in the above-mentioned method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, the vibration performance parameter is the MSD parameter.

[0046] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0047] This invention provides a method for analyzing the vibration performance and imaging quality of a lithography machine stage, comprising: designing a test mask with characteristic test patterns; performing exposure imaging based on a target lithography machine and the test mask at a preset lithography technology node to obtain target imaging parameters; wherein the vibration performance parameters of the target lithography machine at the preset lithography technology node meet the target requirements; establishing a relational model based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters; performing exposure imaging based on the test mask and the lithography machine to be analyzed at the preset lithography technology node to obtain imaging parameters to be analyzed; and obtaining the vibration performance parameters of the lithography machine to be analyzed based on the imaging parameters to be analyzed and the relational model. This analysis method, by forming characteristic test patterns related to the extreme motion and resolution of the lithography machine on the designed test mask, performing lithography and development imaging, and combining the established relational model, quantitatively feedbacks the vibration performance of the lithography machine stage and the extreme imaging capability of the lithography machine to be analyzed, providing quantitative analysis indicators for the stable operation and mass production quality of different lithography machines. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0049] Figure 1 This is a schematic diagram illustrating the exposure principle of a projection lithography machine.

[0050] Figure 2 A flowchart illustrating a method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage, provided in an embodiment of the present invention.

[0051] Figures 3-7 A schematic diagram of different feature test patterns provided in embodiments of the present invention;

[0052] Figure 8 This is a schematic diagram illustrating the relationship between line parameters and vibration performance parameters in a one-dimensional variable periodic line structure provided by an embodiment of the present invention;

[0053] Figure 9 This is a schematic diagram illustrating the relationship between line parameters and vibration performance parameters in a line-to-line structure according to an embodiment of the present invention.

[0054] Figure 10 This is a schematic diagram illustrating the relationship between line parameters and vibration performance parameters in a line-to-line structure provided by an embodiment of the present invention.

[0055] Figure 11 This is a schematic diagram illustrating the relationship between the edge roughness parameter and vibration performance parameter of a one-dimensional variable periodic line structure provided in an embodiment of the present invention.

[0056] Figure 12 This is a schematic diagram illustrating the relationship between process window parameters and vibration performance parameters in a one-dimensional variable periodic linear structure provided by an embodiment of the present invention;

[0057] Figure 13 This is a schematic diagram illustrating the relationship between process window parameters and vibration performance parameters in a line-to-line structure according to an embodiment of the present invention.

[0058] Figure 14 This is a schematic diagram illustrating the relationship between process window parameters and vibration performance parameters in a line-to-line structure according to an embodiment of the present invention.

[0059] Figure 15 This is a schematic diagram of a CDU calculation method provided in an embodiment of the present invention. Detailed Implementation

[0060] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0061] Based on the background art, this invention addresses the resolution and equipment matching issues faced by new lithography machines entering mass production, as well as the changes in vibration performance caused by long-term operation of the lithography machine or variations in vibration performance at different speeds. Therefore, a method for analyzing the vibration performance and imaging quality of the lithography machine's workpiece stage is proposed. The core of this method involves forming characteristic test patterns related to the lithography machine's extreme motion and resolution on a designed test mask, performing lithography and development imaging, and combining this with the relationship model proposed in this application. This provides quantitative feedback on the vibration performance of the lithography machine's workpiece stage and its extreme imaging capabilities, offering quantitative analytical indicators for the stable operation and mass production quality of different lithography machines.

[0062] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0063] refer to Figure 2 , Figure 2This is a flowchart illustrating a method for analyzing the vibration performance and imaging quality of a lithography machine stage according to an embodiment of the present invention. The method includes:

[0064] S101: Design a test mask, wherein the test mask has a characteristic test pattern.

[0065] Specifically, based on step S101, such as Figures 3-5 The feature test graphic shown includes a one-dimensional line graphic, such as... Figure 3 As shown, the one-dimensional line graph includes a dense line graph of the first cycle, such as... Figure 4 As shown, the one-dimensional line graph also includes a semi-dense line graph of the second period, such as... Figure 5 As shown, one-dimensional line graphics also include isolated line graphics of the third period, where the first period is smaller than the second period and the third period. The dense line graphics of the first period, the semi-dense line graphics of the second period, and the isolated line graphics of the third period can also be called one-dimensional variable period line graphics.

[0066] like Figure 6 As shown, the feature test pattern can also include line-to-line end patterns; such as Figure 7 As shown, the feature test graphic can also include line-to-line graphics; it should be noted that... Figure 7 The line-end-to-line graphic shown can also be called a bidirectional line graphic, that is, some lines extend in the horizontal direction and some lines extend in the vertical direction.

[0067] in, Figures 3-7 In the feature test pattern shown, the black area is the light-blocking area of ​​the test mask, and the blank area is the light-transmitting area of ​​the test mask.

[0068] It should be noted that other forms of feature test patterns can be designed based on actual needs; only these are used in this embodiment of the invention. Figures 3-7 The feature test graph shown is used as an example for illustration.

[0069] In some optional embodiments of the present invention, one possible way to implement "designing a test mask, wherein the test mask has a feature test pattern" in step S101 is as follows:

[0070] Obtain the limit resolution of the lithography machine to be analyzed at the preset lithography technology node.

[0071] Based on the preset lithography technology node and the limit resolution, the minimum feature parameters of the feature test pattern are determined.

[0072] The feature test pattern is designed based on the minimum feature parameter to form a test mask with the feature test pattern.

[0073] Specifically, in this embodiment, the minimum feature parameter of the feature test pattern on the test mask is related to the lithography technology node of the lithography machine to be analyzed, as well as the limit resolution corresponding to the lithography technology node. Depending on the lithography technology node and the corresponding limit resolution, the minimum feature parameter of the feature test pattern will also be different.

[0074] For example, for the 5nm lithography technology node, the minimum feature parameter for designing a feature test pattern is 16nm, the minimum period is 32nm, and the variable period range increases from 32nm to over 100nm. The minimum dimension in the line-to-line pattern (i.e., the spacing between line ends) is 20nm-60nm. For example, for the 7nm lithography technology node, the minimum feature parameter for designing a feature test pattern is 20nm, the minimum period is 40nm, and the variable period range increases from 40nm to over 120nm. For example, for the 14nm lithography technology node, the minimum feature parameter for designing a feature test pattern is 32nm, the minimum period is 64nm, and the variable period range increases from 64nm to over 200nm.

[0075] At this point, the test mask of the feature test pattern designed in this way is used for exposure imaging. Only then can the final imaging result parameters effectively reflect the current imaging quality, thereby improving the accuracy of the final analysis result between the vibration performance of the workpiece stage and the imaging quality of the lithography machine to be analyzed.

[0076] like Figures 3-5 As shown, the feature test pattern includes multiple light-shielding strips 11 arranged at intervals along a first direction X1; the light-shielding strips 11 extend along a second direction X2, and the first direction X1 is perpendicular to the second direction X2; wherein, the minimum feature parameter is the width of the light-shielding strip 11 in the first direction X1.

[0077] It should be noted that, Figures 3-5 The difference lies in the different cycles.

[0078] like Figure 6 As shown, the feature test pattern includes multiple first light-shielding strips 11a arranged at intervals along a third direction X3, and multiple second light-shielding strips 11b arranged at intervals along the third direction X3; both the first light-shielding strips 11a and the second light-shielding strips 11b extend along a fourth direction X4, and the third direction X3 is perpendicular to the fourth direction X4; in the fourth direction X4, the first light-shielding strips 11a and the second light-shielding strips 11b are arranged at intervals; wherein, the minimum feature parameter is the interval between the first light-shielding strips 11a and the second light-shielding strips 11b in the fourth direction X4.

[0079] like Figure 7 As shown, the feature test pattern includes multiple third light-shielding strips 11c and a fourth light-shielding strip 11d arranged sequentially at intervals along the fifth direction X5; the third light-shielding strips 11c extend along the sixth direction X6, and the fifth direction X5 is perpendicular to the sixth direction X6; the fourth light-shielding strip 11d extends along the fifth direction X5, and on the sixth direction X6, the fourth light-shielding strip 11d is located on one side of the third light-shielding strip 11c; wherein, the minimum feature parameter is the interval between the third light-shielding strip 11c and the fourth light-shielding strip 11d on the sixth direction X6.

[0080] S102: Based on the target lithography machine and the test mask, exposure imaging is performed at a preset lithography technology node to obtain target imaging parameters; wherein the vibration performance parameters of the target lithography machine at the preset lithography technology node meet the target requirements.

[0081] S103: Establish a relationship model based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters.

[0082] Specifically, based on steps S102 and S103, the standard deviation of the synchronization error between the mask stage and the wafer stage during operation is used as a parameter to describe the vibration performance of the lithography machine stage. In this embodiment of the invention, the vibration performance parameter is described using the MSD parameter as an example. The MSD parameter reflects the positional jitter of the mask stage and the wafer stage during uniform exposure. This high-frequency change in the relative position of the mask stage and the wafer stage during scanning exposure will lead to image blurring, which will mainly affect parameters such as the linewidth, roughness, and process window of the image pattern in the process.

[0083] The definition formula for MSD is as follows:

[0084]

[0085] Where T represents the duration of the exposure period.

[0086] e(t) represents the position error data with time t as the dependent variable.

[0087] Therefore, in this embodiment of the invention, the mask conditions designed in part of step S101 are used in steps S102 and S103 to conduct experiments to find a model of the relationship between the vibration performance of the lithography machine workpiece stage and the imaging quality.

[0088] In an optional embodiment of the present invention, the target imaging parameters include line parameters in the imaging results.

[0089] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0090] Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line parameters in multiple different imaging results.

[0091] By analyzing the line parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between line parameters and vibration performance is established.

[0092] Specifically, the main approach involves using multiple test masks with different design parameters to find the relationship between line parameters and vibration performance parameters, referencing... Figure 8 , Figure 8 This is a schematic diagram illustrating the relationship between line parameters and vibration performance parameters in a one-dimensional variable-period line structure provided by an embodiment of the present invention. The horizontal axis represents the period (Pitch), and the vertical axis represents the line parameter (CD). In the one-dimensional line structure, the line parameter CD represents... Figures 3-5 The width of the light-shielding strip 11 in the first direction X1, as described in the simulation experiment, is 13nm in linewidth of the one-dimensional line structure (i.e., the width of the light-shielding strip 11 in the first direction X1), with a periodic variation from 26nm to 130nm, and the MSD parameter varying from 1nm to 7nm. Figure 8 As shown, for a one-dimensional variable periodic line structure, CD continues to decrease as the MSD parameter increases. Specifically, for the period from 78nm to 117nm, and the MSD parameter from 1nm to 4nm, CD shows a linear relationship with the change of the MSD parameter.

[0093] refer to Figure 9 , Figure 9 This is a schematic diagram illustrating the relationship between line parameters and vibration performance parameters in a line-to-line structure according to an embodiment of the present invention. The horizontal axis represents the MSD parameter, and the vertical axis represents the line parameter (GAP). In the line-to-line structure, the line parameter GAP represents... Figure 6 The spacing between the first light-shielding strip 11a and the second light-shielding strip 11b on the fourth direction X4, as described in the simulation experiment, is such that the linewidth of the line-to-line structure (i.e., the width of the light-shielding strips 11a and 11b on the third direction X3) is 13nm, the period is 26nm, the GAP varies from 13nm to 25nm, and the MSD parameter varies from 0nm to 20nm. Figure 9As shown, for line-to-line structures, the increase in the MSD parameter leads to a change in GAP that can be divided into three parts: First, as the MSD parameter increases, GAP remains unchanged; second, as the MSD parameter increases, GAP increases slightly; third, as the MSD parameter increases, GAP continuously decreases.

[0094] refer to Figure 10 , Figure 10 This invention provides a schematic diagram illustrating the relationship between line parameters and vibration performance parameters in a line-to-line structure. The horizontal axis represents the MSD parameter, and the vertical axis represents the line parameter (GAP). In the line-to-line structure, the line parameter GAP represents... Figure 7 In the simulation experiment, the spacing between the third light-shielding strip 11c and the fourth light-shielding strip 11d in the sixth direction X6 is 13nm, the line width of the line structure (i.e., the width of the third light-shielding strip 11c in the fifth direction X5 and the width of the fourth light-shielding strip 11d in the sixth direction X6) is 26nm, the GAP varies from 13nm to 25nm, and the MSD parameter varies from 0nm to 8nm. Figure 10 As shown, for line-to-line structures, as the MSD parameter increases, the GAP continuously increases, and the GAP increases with the rate of change of the MSD parameter as the target GAP increases. The target GAP is the previously set GAP, and the actual GAP changes with the change of the MSD parameter.

[0095] In summary, by analyzing the line parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between line parameters and vibration performance is established.

[0096] In an optional embodiment of the present invention, the target imaging parameters include the line edge roughness parameters in the imaging results.

[0097] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0098] Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line edge roughness parameters in multiple different imaging results.

[0099] By analyzing the line edge roughness parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the line edge roughness parameters and vibration performance is established.

[0100] For details, please refer to Figure 11 , Figure 11This is a schematic diagram illustrating the relationship between the edge roughness parameter and vibration performance parameter of a one-dimensional variable-period line structure provided in an embodiment of the present invention. The horizontal axis represents the period (Pitch), and the vertical axis represents the line parameter (LER). In this simulation experiment, the line width of the one-dimensional line structure (i.e., the width of the light-shielding strip 11 in the first direction X1) is 13 nm, the period varies from 26 nm to 130 nm, and the MSD parameter varies from 1 nm to 7 nm. Figure 11 As shown, for a one-dimensional variable periodic line structure, as the MSD parameter increases, the LER continuously decreases, with the edge roughness parameter of the uniform width line showing the most significant change with the MSD parameter.

[0101] In summary, by analyzing the line edge roughness parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between line edge roughness parameters and vibration performance is established.

[0102] In an optional embodiment of the present invention, the target imaging parameters include the process window parameters in the imaging results.

[0103] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0104] Under the preset lithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain process window parameters in multiple different imaging results.

[0105] By analyzing the process window parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the process window parameters and vibration performance is established.

[0106] Specifically, the main approach involves using multiple test masks with different design parameters to explore the relationship between process window parameters and vibration performance parameters, referencing... Figure 12 , Figure 12 This is a schematic diagram illustrating the relationship between process window parameters and vibration performance parameters in a one-dimensional variable-period line structure provided by an embodiment of the present invention. The horizontal axis DOF ​​(Depth of Focus) represents the defocusing amount, and the vertical axis EL (Energy Latitude) represents the energy margin. The process window parameters mainly include the energy margin and the defocusing amount. In this simulation experiment, the linewidth of the one-dimensional line structure (i.e., the width of the light-shielding strip 11 in the first direction X1) is 13 nm, the period is 26 nm, and the MSD parameters are 2 nm and 6 nm. Figure 12 As shown, for a one-dimensional variable periodic line structure, changes in the MSD parameter have a significant impact on the energy margin, but a relatively minor impact on the defocus amount.

[0107] refer to Figure 13 , Figure 13 This is a schematic diagram illustrating the relationship between process window parameters and vibration performance parameters in a line-to-line structure according to an embodiment of the present invention. The horizontal axis DOF ​​represents defocusing, and the vertical axis EL represents energy margin. The process window parameters mainly include energy margin and defocusing. In this simulation experiment, the linewidth of the line-to-line structure (i.e., the width of the light-shielding strips 11a and 11b on the third direction X3) is 13 nm, and GAP (representing...) is... Figure 6 The spacing between the first light-shielding strip 11a and the second light-shielding strip 11b in the fourth direction X4 is 15nm, and the MSD parameters are 2nm and 6nm, as described above. Figure 13 As shown, for line-to-line structures, changes in the MSD parameter have a very significant impact on both the energy margin and the amount of defocus.

[0108] refer to Figure 14 , Figure 14 This invention provides a schematic diagram illustrating the relationship between process window parameters and vibration performance parameters in a line-to-line structure. The horizontal axis DOF ​​represents defocusing, and the vertical axis EL represents energy margin. The process window parameters mainly include energy margin and defocusing. In this simulation experiment, the linewidth of the line-to-line structure (i.e., the width of the third light-shielding strip 11c in the fifth direction X5 and the width of the fourth light-shielding strip 11d in the sixth direction X6) is 13 nm, and GAP ( Figure 7 The interval between the third light-shielding strip 11c and the fourth light-shielding strip 11d in the sixth direction X6 is 15nm, and the MSD parameters are 2nm and 6nm, as shown. Figure 14 As shown, for line-to-line structures, changes in the MSD parameter have a very significant impact on energy margin and defocus amount.

[0109] In summary, by analyzing the process window parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the process window parameters and vibration performance is established.

[0110] In an optional embodiment of the present invention, the target imaging parameters include the line uniformity parameter in the imaging result.

[0111] The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes:

[0112] Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line uniformity parameters in multiple different imaging results.

[0113] By analyzing the line uniformity parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the line uniformity parameters and vibration performance is established.

[0114] For details, please refer to Figure 15 , Figure 15 This diagram illustrates a CDU calculation method provided in an embodiment of the present invention. It primarily considers the relationship between the uniformity of one-dimensional lines and vibration performance parameters under low-frequency vibration. Vibration during the workpiece stage movement mainly affects energy uniformity, and this effect is more pronounced in low-frequency vibration. For one-dimensional line structures, uneven energy distribution during exposure directly leads to an increase in the CDU (Critical Dimension Uniform) of the lines. The low-frequency vibration performance of the lithography machine's workpiece stage can be reflected by calculating the changes in CDU in different regions. The CDU calculation method is as follows: Figure 15 As shown, a suitable exposure area is selected from all the exposure areas of the entire wafer, and the linewidth of the test mask in this area is measured to calculate the average linewidth of different areas.

[0115] In summary, by analyzing the line uniformity parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the line uniformity parameters and vibration performance is established.

[0116] S104: Based on the test mask and the lithography machine to be analyzed, exposure imaging is performed at the preset lithography technology node to obtain the imaging parameters to be analyzed.

[0117] S105: Based on the imaging parameters to be analyzed and the relationship model, the vibration performance parameters of the lithography machine to be analyzed are obtained.

[0118] Specifically, as seen in the relational model designed in the above steps, for different test masks and under the influence of different MSD parameters, the imaging parameters of the reaction lithography machine, including line parameters, line edge roughness parameters, process window parameters, and line uniformity parameters, all undergo significant changes. For a trustworthy target lithography machine, exposure experiments are conducted using appropriate lithography conditions for different lithography technology nodes based on different test masks, and experimental data is collected to establish the relational model.

[0119] Subsequently, key data of test masks from different lithography machines or different stages of lithography machines were measured, and the vibration relationship of the workpiece stage was analyzed in reverse. Through the established relationship model, the relationship between different vibration intensities and imaging quality was constructed. In the actual measurement process, by measuring key dimensions, line edge roughness parameters, and process window parameters of the test mask, the quality monitoring, operational stability, and time consistency of the lithography machine equipment were achieved.

[0120] In other words, this application discloses a method for evaluating the vibration performance of a lithography machine by monitoring the imaging parameters of the pattern after exposure. Simulation experiments using different test masks show that as the stage vibration changes, the linewidth, edge roughness, and process window of various patterns after exposure also change significantly. The overall logic is to first select the exposure parameters of a target lithography machine with good stage motion quality as a standard value. Then, when monitoring the stage motion quality of other lithography machines, this standard value can be used as a reference to evaluate the stage motion quality of the monitored lithography machines. This method is simple and easy to operate, and the results are reliable through comparison with actual data.

[0121] The above provides a detailed description of the method for analyzing the vibration performance and imaging quality of a lithography machine workpiece stage provided by the present invention. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

[0122] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0123] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that elements inherent to a process, method, article, or apparatus that comprises a list of elements, or elements inherent to such processes, methods, articles, or apparatus, are also included. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0124] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of analyzing lithography tool stage vibration performance and imaging quality, the method comprising: The analytical method includes: ​ Design a test mask, wherein the test mask has a characteristic test pattern; Based on the target lithography machine and the test mask, exposure imaging is performed at a preset lithography technology node to obtain target imaging parameters; wherein the vibration performance parameters of the target lithography machine at the preset lithography technology node meet the target requirements. A relationship model is established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters; Based on the test mask and the lithography machine to be analyzed, exposure imaging is performed at the preset lithography technology node to obtain the imaging parameters to be analyzed. Based on the imaging parameters to be analyzed and the relationship model, the vibration performance parameters of the lithography machine to be analyzed are obtained; The design test mask has a feature test pattern, including: Obtain the limit resolution of the lithography machine to be analyzed at the preset lithography technology node; Based on the preset lithography technology node and the limit resolution, the minimum feature parameters of the feature test pattern are determined; The feature test pattern is designed based on the minimum feature parameter to form a test mask with the feature test pattern; The feature test pattern includes multiple light-blocking strips arranged at intervals along a first direction; The light-shielding strip extends along a second direction, and the first direction is perpendicular to the second direction; Wherein, the minimum characteristic parameter is the width of the light-shielding strip in the first direction; The target imaging parameters include the line parameters in the imaging results; The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes: Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line parameters in multiple different imaging results; By analyzing the line parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between line parameters and vibration performance is established. The vibration performance parameters are MSD parameters.

2. The analysis method according to claim 1, characterized in that, The feature test pattern includes multiple first light-blocking strips arranged at intervals along a third direction, and multiple second light-blocking strips arranged at intervals along the third direction. Both the first light-shielding strip and the second light-shielding strip extend along the fourth direction, and the third direction is perpendicular to the fourth direction; In the fourth direction, the first light-shielding strip and the second light-shielding strip are arranged at intervals; The minimum characteristic parameter is the interval between the first light-shielding strip and the second light-shielding strip in the fourth direction.

3. The analysis method of claim 1, wherein, The feature test pattern includes multiple third light-blocking strips and a fourth light-blocking strip arranged at intervals along the fifth direction; The third light-shielding strip extends along the sixth direction, and the fifth direction is perpendicular to the sixth direction; The fourth light-shielding strip extends along the fifth direction, and in the sixth direction, the fourth light-shielding strip is located on one side of the third light-shielding strip; The minimum characteristic parameter is the interval between the third and fourth light-shielding strips in the sixth direction.

4. The analytical method according to claim 1, characterized in that, The target imaging parameters include the line edge roughness parameters in the imaging results; The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes: Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line edge roughness parameters in multiple different imaging results; By analyzing the line edge roughness parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the line edge roughness parameters and vibration performance is established.

5. The analytical method according to claim 1, characterized in that, The target imaging parameters include the process window parameters in the imaging results; The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes: Under the preset lithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain process window parameters in multiple different imaging results; By analyzing the process window parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the process window parameters and vibration performance is established.

6. The analytical method according to claim 1, characterized in that, The target imaging parameters include the line uniformity parameters in the imaging results; The relationship model established based on the design parameters of the test mask, the preset lithography technology node, the vibration performance parameters of the target lithography machine, and the target imaging parameters includes: Under the preset photolithography technology node, exposure imaging is performed based on multiple test masks with different design parameters to obtain line uniformity parameters in multiple different imaging results; By analyzing the line uniformity parameters and vibration performance parameters of the target lithography machine in multiple different imaging results, a relationship model between the line uniformity parameters and vibration performance is established.

Images