Method and device for determining edge position error and storage medium

Abstract

The embodiment of the invention provides a method and equipment for determining an edge position error and a storage medium. The method includes determining a degree of signal variation of a lithographic simulation signal for a control point in a mask pattern at a current position of the lithographic simulation pattern; updating the position of the control point in the photoetching simulation pattern according to the signal change degree of the photoetching simulation signal of the control point at the current position so as to determine the target position of the control point; and determining an edge position error of the control point based on the difference between the initial position and the target position of the control point. In this way, the efficiency of determining the edge position error can be improved, and then the efficiency of optical proximity effect correction is improved.

Description

Technical Field

[0001] The embodiments of this disclosure are primarily related to the field of integrated circuit technology, and more specifically, to methods, apparatus, and storage media for determining edge position errors. Background Technology

[0002] As semiconductor manufacturing processes continue to evolve towards smaller feature sizes, the imaging accuracy requirements for patterns during photolithography become increasingly stringent. Due to the physical limitations of optical systems, the imaging of mask patterns on the wafer often deviates. To compensate for these deviations, Optical Proximity Correction (OPC) is widely used in advanced processes. The core objective of OPC is to iteratively correct the mask pattern to ensure that its imaging on the wafer closely matches the target design pattern. In this process, the calculation of Edge Placement Error (EPE) is a crucial step guiding the iterative correction. Summary of the Invention

[0003] In a first aspect of this disclosure, a method for determining edge position error is provided. The method includes: determining the degree of signal change of a photolithographic simulation signal for a control point in a mask pattern at a current position in the photolithographic simulation pattern; updating the position of the control point in the photolithographic simulation pattern based on the degree of signal change of the photolithographic simulation signal at the current position to determine a target position of the control point; and determining the edge position error of the control point based on the difference between the initial position and the target position of the control point.

[0004] In a second aspect of this disclosure, an electronic device is provided. The electronic device includes a processor and a memory coupled to the processor. The memory has instructions stored therein, which, when executed by the processor, cause the electronic device to perform a method according to a first aspect of this disclosure.

[0005] In a third aspect of this disclosure, a computer-readable storage medium is provided. A computer program is stored on the computer-readable storage medium. When executed by a processor, the computer program implements the method according to a first aspect of this disclosure.

[0006] As will be understood from the following description, according to embodiments of this disclosure, the degree of signal change of the photolithographic simulation signal for a control point in the mask pattern at its current position in the photolithographic simulation pattern can first be determined. Further, the position of the control point in the photolithographic simulation pattern can be updated based on the degree of signal change of the photolithographic simulation signal at its current position, thereby determining the target position of the control point. Further still, the edge position error of the control point can be determined based on the difference between the initial position and the target position. In this way, the computational efficiency of the edge position error can be improved, thereby effectively enhancing the efficiency of mask pattern correction.

[0007] It should be understood that the content described in this summary section is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0008] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein: Figure 1 A schematic diagram of an example environment in which the various embodiments of this disclosure can be implemented is shown; Figure 2 A schematic diagram illustrating the process of determining the target location of a control point according to some embodiments of the present disclosure is shown; Figure 3 A flowchart illustrating a process for determining edge position errors according to some embodiments of the present disclosure is shown; and Figure 4 A block diagram of an electronic device in which one or more embodiments of the present disclosure may be implemented is shown. Detailed Implementation

[0009] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0010] In the description of embodiments of this disclosure, the term "comprising" and similar terms should be understood as open-ended inclusion, i.e., "including but not limited to". The term "based on" should be understood as "at least partially based on". The term "one embodiment" or "the embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0011] The following will describe in detail various example implementations of this scheme with reference to the accompanying drawings.

[0012] First see Figure 1 It illustrates a schematic diagram of an example environment 100 in which the various embodiments of this disclosure can be implemented. For example... Figure 1 As shown, the example environment 100 may generally include electronic device 110.

[0013] In some embodiments, the electronic device 110 can interact with other devices (not shown). For example, the electronic device 110 can receive input information from other devices and output feedback information to other devices. In some embodiments, the input message from other devices can be design layout data 120. The electronic device 110 can perform corresponding mathematical operations on the design layout data and output the corresponding operation result 130 to other devices. In some embodiments, the operation result can be corrected layout data.

[0014] In example environment 100, electronic device 110 can be any type of computing-capable device, including terminal devices or server devices. Terminal devices can be any type of mobile terminal, fixed terminal, or portable terminal, including mobile phones, desktop computers, laptop computers, notebook computers, netbook computers, tablet computers, media computers, multimedia tablets, personal communication system (PCS) devices, personal navigation devices, personal digital assistants (PDAs), audio / video players, digital cameras / camcorders, positioning devices, television receivers, radio receivers, e-book devices, gaming devices, or any combination of the foregoing, including accessories and peripherals of these devices or any combination thereof. Server devices can include, for example, computing systems / servers, such as mainframes, edge computing nodes, computing devices in cloud environments, and so on.

[0015] It should be understood that the structure and function of environment 100 are described for illustrative purposes only and do not imply any limitation on the scope of this disclosure. Exemplary embodiments according to this disclosure will now be described in detail with reference to the accompanying drawings.

[0016] As briefly mentioned above, optical proximity correction (OPC) is an important method for improving the accuracy of photolithography processes in semiconductor manufacturing. To reduce the deviation of the mask pattern caused by the optical proximity effect during imaging, OPC correction typically involves iterative calculation and correction of the mask pattern to ensure that the final lithographic image is as close as possible to the target design. In this process, edge position error is the key parameter determining the direction and magnitude of correction in each iteration.

[0017] Edge position error can be understood as the distance between the control points on the mask segment and the wafer imaging contour. Its magnitude directly determines the amount of segment movement, thus affecting the final correction accuracy of the mask pattern. The mask corrected by OPC can achieve better pattern linewidth control and a wider lithography process window.

[0018] In related techniques, edge position error is typically calculated based on control points on a segment, and the target contour is found along the normal vector direction passing through the control points. However, searching along a fixed direction does not always lead to a fast and accurate finding of the corresponding pixel. Furthermore, related techniques include numerical solutions using Newton's method. While this method has an advantage in convergence speed, it requires calculating second-order discrete gradients, resulting in high computational complexity per iteration and increasing overall computational overhead.

[0019] To address this, embodiments of the present disclosure propose a scheme for determining edge position errors. According to embodiments of the present disclosure, firstly, the degree of signal change of the photolithographic simulation signal for a control point in a mask pattern at its current position within the photolithographic simulation pattern can be determined. Further, the position of the control point in the photolithographic simulation pattern can be updated based on the degree of signal change of the photolithographic simulation signal at its current position, thereby determining the target position of the control point. Still further, the edge position error of the control point can be determined based on the difference between the initial position and the target position of the control point.

[0020] In the embodiments of this disclosure, the position of the control points is iteratively updated based on the degree of change in the photolithographic analog signal. This method enables faster and more accurate calculation of edge position errors. Furthermore, it allows for efficient parallel computation while maintaining accuracy, thus meeting the speed and accuracy requirements of OPC correction.

[0021] The following describes various example implementations of this scheme in further detail with reference to the accompanying drawings. In some embodiments, the process of determining the mask pattern described above can be performed by, for example... Figure 1 The electronic device 110 shown is performing this operation. The following is in conjunction with... Figure 1 Let me explain in detail.

[0022] In some embodiments, electronic device 110 can determine the degree of signal variation of a photolithographic simulation signal for a control point in a mask pattern at the current position of the photolithographic simulation pattern. The photolithographic simulation pattern is obtained by photolithographic simulation of the mask pattern. For example, electronic device 110 can divide the mask pattern into multiple segments. Each segment corresponds to a region. For each region, electronic device 110 can perform optical imaging calculations to obtain the photolithographic simulation result of that region on the wafer.

[0023] In some examples, the photolithographic simulation result of the mask pattern can be represented as the light intensity distribution of that region on the wafer. To facilitate the determination of boundary positions, the electronic device 110 can perform thresholding on the light intensity distribution based on a threshold representing the critical condition for photoresist exposure, thereby obtaining a threshold map. In other words, the threshold map includes the graphic contour extracted from the light intensity distribution under the threshold condition. The electronic device 110 can use this threshold map as the photolithographic simulation pattern corresponding to the mask pattern, providing basic data for calculating the error of the control point edge position.

[0024] In some embodiments, the electronic device 110 may determine at least one control point for each segment. The control point is a key sampling point characterizing the boundary position of the segment. By iteratively updating the control points, the actual imaging boundary position can be approximated, thereby more accurately reflecting the actual imaging effect of the mask pattern on the wafer.

[0025] In related technologies, boundaries are found solely by iteratively updating control points along a fixed direction. However, this method of finding pixels corresponding to the contour along a fixed direction fails to consider the dynamic characteristics of signal change directions, resulting in limited convergence efficiency. In embodiments of this disclosure, the direction for iteratively updating the control points can be determined based on signal changes at the control points.

[0026] In some embodiments, the electronic device 110 can update the position of the control point in the photolithographic simulation pattern along the direction indicated by the degree of signal change. In other words, the actual trend of signal change can indicate the direction of control point movement. In this way, the control point can avoid being limited by a fixed direction during the iteration process, thereby achieving more efficient and accurate edge position approximation.

[0027] In some embodiments, the electronic device 110 can determine the direction and step size of the control point movement based on the degree of signal change of the photolithographic analog signal at the current position of each control point. In this way, the target boundary position of the mask pattern can be found more flexibly and quickly, thereby improving the accuracy and stability of iterative convergence while reducing computational burden.

[0028] As an example, electronic device 110 can first determine the initial position of the control points. The initial position of the control points can be used to characterize the boundary positions expected during the mask pattern design phase, i.e., the target contour points defined in the design data. For example, in some embodiments, the initial position of the control points can be represented in polar coordinates. Furthermore, the electronic device 110 can dynamically update the position of the control point based on the degree of signal change of the photolithographic simulation signal at the current position of the photolithographic simulation pattern.

[0029] In some embodiments, the electronic device 110 can calculate the degree of signal change of the photolithographic analog signal at the current position in a first direction and a second direction. The first direction is different from the second direction. For example, the first direction can be a lateral direction, and the second direction can be a longitudinal direction. Further, the electronic device 110 can determine the degree of signal change of the photolithographic analog signal at the current position based on the degree of signal change in the first direction and the second direction.

[0030] By calculating the degree of signal change in two distinct directions, the information loss problem caused by single-direction calculation can be avoided, thus more accurately reflecting the local change trend of the lithographic simulation signal at the current position. Therefore, when iteratively updating the position of the control point, a more reasonable update direction and magnitude can be obtained.

[0031] In some embodiments, the degree of signal variation of the photolithographic analog signal may include the gradient of the photolithographic analog signal. The electronic device 110 may calculate the gradient component of the photolithographic analog signal at the current position on the photolithographic analog pattern, based on the signal distribution of the control point at the current position.

[0032] In some embodiments, the current position of the control point is represented by polar coordinates. In mask patterns and lithographic simulation results, the boundary often appears as a closed curve or an approximately circular structure. Representing the current position of the control point using polar coordinates can more intuitively describe the radial offset and angular changes of the boundary point, thereby simplifying the calculation of the position convergence of the boundary point during imaging.

[0033] In some embodiments, the electronic device 110 can first convert the coordinates of the control point at its current position from polar coordinates to Cartesian coordinates. In the Cartesian coordinate system, the electronic device 110 can calculate the lateral and longitudinal gradients of the control point at its current position by performing differential operations on the lithographic analog signals of adjacent grid points. Furthermore, the electronic device 110 can convert the lateral and longitudinal gradients into radial and angular gradients in polar coordinates, thereby fully characterizing the signal change of the control point in the polar coordinate system.

[0034] As an example, in calculating the degree of signal change at a control point, electronic device 110 can convert the polar coordinate representation of the control point at its current position to a Cartesian coordinate representation. For example, if the current position of the control point is... Then, electronic device 110 can be converted to its representation in Cartesian coordinates. .

[0035] Furthermore, the electronic device 110 can calculate the gradient of the lithographic analog signal at the current position of the control point according to the following formula: (1) I represents the light intensity distribution function of the photolithographic simulation pattern obtained by photolithographic simulation of the mask pattern. It can represent the position of the control point after the nth update. The photolithographic analog signal value at the current position is used. In a Cartesian coordinate system, the electronic device 110 can calculate the gradient components in the horizontal and vertical directions for the photolithographic analog signal value of the control point at its current position. For example, the position of the control point after the nth update can be obtained through differential or interpolation methods. lateral gradient at the location and longitudinal gradient Based on this, the electronic device 110 can convert the gradient components in the Cartesian coordinate system into gradient components in the polar coordinate system, such as the radial gradient. and angular gradient . These represent the radial and angular coordinates of the control point in the polar coordinate system after the nth position update, respectively.

[0036] In this way, the electronic device 110 can simultaneously acquire the degree of signal change in the radial and angular directions in the polar coordinate system, thereby more accurately characterizing the photolithographic analog signal distribution characteristics of the control point at the current position.

[0037] In some embodiments, the electronic device 110 can determine the target position of the control point by updating its position in the photolithographic simulation pattern based on the degree of signal change of the photolithographic simulation signal at the current position. For example, the electronic device 110 can use the initial position of the control point as the starting point for position updating. During each update, the electronic device 110 can determine the update direction of the control point based on the degree of signal change at the current position. The electronic device 110 can adjust the position of the control point based on a preset step size parameter.

[0038] In some embodiments, the direction of control point position update can be determined by the gradient of the lithographic simulation signal at the current position of the control point. Unlike related technologies that update only along the boundary normal direction of the control point, the electronic device 110 can dynamically change the position update direction during the iteration process. For example, the electronic device 110 can first calculate the lateral and longitudinal gradients of the control point in Cartesian coordinates and use them as the update direction of the control point's current position. Subsequently, the electronic device 110 can move the control point to the new position in the lateral and longitudinal directions according to the proportions corresponding to the gradient components, respectively. In this way, the iteration path of the control point can be dynamic, for example, it may be along the normal direction or it may be an oblique path. In this way, the imaging boundary point corresponding to the control point can be found more accurately and quickly, thereby improving the calculation efficiency of subsequent edge position errors.

[0039] In some embodiments, the electronic device 110 can update the position of the control point in the photolithographic simulation pattern based on the gradient and a predetermined step size, along the negative direction of the gradient. The electronic device 110 can use the gradient of the control point at its current position as a reference for the search direction and move the control point in the opposite direction. During the calculation of the edge position error, it is necessary to find the position where the light intensity signal drops to a predetermined threshold. Therefore, the electronic device 110 can choose to update along the negative direction of the gradient to ensure that the control point gradually approaches the threshold boundary.

[0040] As an example, electronic device 110 can update the position of the control point in the photolithographic simulation pattern according to the following formula: (2) Where α represents the predetermined step size. This represents the radial and angular coordinates of the control point in the polar coordinate system after this update (i.e., the (n+1)th position update). These represent the radial gradient and angular gradient of the control point at its current position, respectively. After updating in polar coordinates, the electronic device 110 can further convert the updated coordinates to a Cartesian coordinate system. This facilitates subsequent calculations for the photolithographic simulation pattern.

[0041] In some embodiments, the electronic device 110 can further incorporate historical update results of the control point positions to improve the convergence stability of the iterative process. For example, during the position update process, the electronic device 110 can also refer to the update direction and update magnitude obtained in the previous iteration, thereby establishing a correlation between the gradient direction of the current position and the historical update direction.

[0042] In this way, during the update of the current position, the electronic device 110 can not only adjust according to the current gradient, but also continue the trend of the previous position update to a certain extent, making the movement direction of the control point smoother and more stable. For example, if the control point has shifted significantly in a certain direction after the previous position update, the electronic device 110 can further add a certain amount of update in that direction in the next position update, thereby accelerating the convergence speed towards the target position.

[0043] In some embodiments, the electronic device 110 can determine the velocity vector of the control point at its current position based on the gradient of the photolithographic analog signal of the control point at the current position and the historical update results of the control point's position. The velocity vector can be understood as an auxiliary variable describing the movement trend of the control point during the update process. The velocity vector not only reflects the instantaneous update direction indicated by the gradient of the current position, but also incorporates the existing movement directions in historical iterations, thereby providing a more stable reference for the next update.

[0044] In some embodiments, the historical update results include the velocity vector of the control point at the most recently updated position. The velocity vector at the most recently updated position refers to the velocity vector obtained after the position update was completed in the previous iteration. By referencing the velocity vector from the previous iteration during the update process, the previous movement trend can be continued in the update of the current position.

[0045] In some embodiments, the electronic device 110 can weight the velocity vector of the control point at the most recently updated position and the gradient of the lithographic analog signal of the control point at the current position based on predetermined weights. Based on the weighted result, the electronic device 110 can determine the velocity vector of the control point at the current position. In this way, the velocity vector at the current position includes both the immediate direction information provided by the current gradient and the update trend accumulated from historical iterations, thereby enabling smoother and more efficient position updates.

[0046] As an example, electronic device 110 can determine the velocity vector of the control point at its current position according to the following formula: (3) in These represent the radial and angular velocity vector components at the current position, respectively. β represents the predetermined weight, which can also be understood as the momentum coefficient. The value of β can range from 0 to 1, and is used to control the degree of influence of historical update results on the current position update. These represent the radial and angular components of the velocity vector obtained after the most recent update, respectively. These represent the radial gradient component and the angular gradient component of the lithographic simulation signal at the current position, respectively.

[0047] In this way, determining the velocity vector of a control point relies not only on the gradient information of the current position but also on the update direction from the previous iteration. This method, to some extent, simulates the "momentum effect" in physical processes, where motion behavior does not change instantaneously but gradually adjusts direction and velocity. A larger value of β indicates a stronger influence of historical updates. Updates at the current position tend to maintain the previous motion trend, thus reducing oscillations during iteration. A smaller value of β indicates that updates at the current position rely more on current gradient information, enabling a faster response to new signal changes. Therefore, the velocity vector can guide the gradual convergence of the control point position while balancing stability and sensitivity.

[0048] In some embodiments, the electronic device 110 can update the position of the control point along the negative direction of the velocity vector, based on the velocity vector and a predetermined step size. Updating along the negative direction of the velocity vector means that the position of the control point will move in a direction that reduces the difference of the lithographic analog signal, thereby gradually approaching the true boundary of the lithographic analog pattern.

[0049] In some embodiments, a predetermined step size can be used to adjust the magnitude of each update. If the step size is too large, the control point may oscillate near the boundary or overshoot the target position. If the step size is too small, the control point can converge more stably, but more iterations may be required to reach the target position. Therefore, in practical applications, the step size is usually set according to the complexity of the mask pattern, optical conditions, and the required convergence speed to achieve a balance between convergence speed and convergence accuracy.

[0050] As an example, electronic device 110 can update the position of the control point in the photolithographic simulation pattern according to the following formula: (4) in These represent the radial and angular coordinates of the control point in polar coordinates after the nth update, respectively. These represent the radial and angular coordinates of the control point in polar coordinates after the (n+1)th update, respectively. α represents the step size, used to control the magnitude of each position update. These represent the radial velocity component and the angular velocity component at the current position, respectively.

[0051] In this way, the position of the control point is adjusted along the negative direction of the velocity vector in each iteration. The velocity vector takes into account both the current gradient information and the historical update trend. Therefore, this position update method can gradually approach the target boundary position while avoiding update oscillations caused by drastic fluctuations in the gradient direction. In some scenarios, this position update method that combines historical update results can effectively accelerate the convergence speed of the update, enabling the control point to reach the target boundary position in the lithographic simulation pattern more quickly.

[0052] In some embodiments, the electronic device 110 can determine the signal strength of the photolithographic analog signal of the control point at the updated position. Further, in response to the signal strength meeting a signal strength threshold or the number of updates reaching a threshold number, the electronic device 110 can determine the updated position as the target position of the control point.

[0053] As an example, after each update of the control point's position, the electronic device 110 can determine the photolithographic simulation signal intensity value at that position on the photolithographic simulation pattern. Furthermore, the electronic device 110 can determine whether to terminate the iteration process based on this signal intensity value. For instance, if the signal intensity at the updated position meets a preset signal intensity threshold, indicating that the position has approached the target boundary, the electronic device 110 can determine the updated position as the target position of the control point.

[0054] As another example, if the control point still fails to reach the signal strength threshold after multiple iterations, the electronic device 110 can terminate the position update iteration process based on a preset update count threshold, and use the position of the control point at the end of the iteration as the target position. In this way, while ensuring solution accuracy, the waste of computational resources caused by excessive iterations can be avoided, thereby improving the overall solution efficiency.

[0055] Alternatively or additionally, the electronic device 110 can determine whether the updated position falls within a preset constraint area after each update of the control point's position. If the updated position is found to exceed the constraint area, the electronic device 110 can terminate the update process and treat the current position as the final position. In this way, control points can be prevented from entering invalid or erroneous areas, thereby further improving the stability and robustness of the calculation process.

[0056] As an example, Figure 2A schematic diagram of a process 200 for determining the target position of a control point according to some embodiments of the present disclosure is shown. As shown, electronic device 110 can determine the edge position error of the control point based on photolithographic simulation results. For example, after the original mask pattern is optically simulated, a corresponding photolithographic simulation pattern 205 is obtained. For ease of processing, the mask pattern can be divided into multiple segments, for example, segment 210. Each segment can correspond to a block region. For each block region of a segment, electronic device 110 can set at least one control point.

[0057] like Figure 2 As shown, control point 211 can be mapped to corresponding grid point positions. In the photolithographic simulation pattern, the imaging boundary region often corresponds to the part where the signal changes most drastically, for example, the boundary grid point region 215. Electronic device 110 can start from the grid point of control point 211, calculate the gradient of the photolithographic simulation signal at that position in the horizontal and vertical directions, and update the position of the control point according to the direction and magnitude of the gradient. In each update process, electronic device 110 can traverse several grid points in the x and y directions according to a preset step size, so that the control point gradually moves along the gradient direction until the position of the control point converges to the boundary grid point region 215. In this way, electronic device 110 can improve the computational efficiency of edge position errors, thereby providing reference data for subsequent optical proximity effect correction.

[0058] In some embodiments, the electronic device 110 can record the position path of the control point during the update process. By recording the position path, the position update trajectory of the control point can be tracked and analyzed, thereby assisting in evaluating the convergence and stability of the update process. For example, the electronic device 110 can initialize an empty path list at the initial stage of the position update process to store the position information of the control point in the polar coordinate system. Furthermore, the electronic device 110 can record the initial position of the control point. Add to the path list. After each update of the control point's location, electronic device 110 can display the new location of the control point. Add to the path list.

[0059] In some embodiments, the electronic device 110 can determine the edge position error of the control point based on the difference between the initial position and the target position of the control point. The initial position of the control point is used to characterize the ideal boundary point defined in the mask pattern during the design phase. The target position of the control point refers to the boundary point position converged after iterative updates in the photolithographic simulation pattern. The difference between the initial position and the target position can represent the offset between the designed pattern and the actual imaging pattern, and can reflect the influence of process factors such as optical proximity effect on the imaging quality of the mask pattern.

[0060] As an example, electronic device 110 can determine the edge position error of the control point according to the following formula: (5) in The initial position of the control point is represented in polar coordinates, reflecting the ideal boundary point corresponding to the mask design stage. This represents the target position of the control point determined through the aforementioned iterative update process in polar coordinates. This corresponds to the actual convergence boundary point in the photolithographic simulation pattern. By calculating the Euclidean distance between these two points, the deviation of this control point from the design boundary and the actual imaging boundary can be quantified, thus obtaining the edge position error of the control point.

[0061] In some embodiments, the mask pattern can be divided into multiple segments, each segment including at least one control point. For each control point, the electronic device 110 can calculate the corresponding edge position error based on the difference between its initial position and the target position.

[0062] Furthermore, the electronic device 110 can determine the edge position error of each segment based on the edge position errors of at least one control point within each segment. For example, the electronic device 110 can take the mean, maximum, or weighted combination of the edge position errors of all control points within the segment as the edge position error of that segment. The edge position error of the segment can be used to reflect the degree of deviation of the segment from the design target during actual imaging.

[0063] In some embodiments, the electronic device 110 may perform optical proximity correction on the mask pattern based on the corresponding edge position errors of multiple segments. For example, the electronic device 110 may use the edge position errors as driving signals for iterative optimization to adjust the geometric parameters of the corresponding mask segments (e.g., boundary position, boundary curvature, or layout of auxiliary patterns).

[0064] As an example, the electronic device 110 can fine-tune the boundary of a mask segment along the direction of the edge position error of each segment. For instance, if the edge position error of the segment is greater than a positive threshold, the electronic device 110 can shift the boundary of the mask segment inward. If the edge position error of the segment is less than a negative threshold, the boundary of the mask segment can be shifted outward. The adjustment range of the mask segment can be proportional to the magnitude of the edge position error or determined by a preset nonlinear function mapping.

[0065] Furthermore, the electronic device 110 can re-execute the simulated imaging based on the updated mask pattern to obtain a new light intensity distribution map and recalculate the edge position error of each control point. The electronic device 110 can repeatedly perform the edge position error calculation and mask pattern correction process until the overall edge position error of the mask pattern meets a predetermined convergence condition. For example, if the average edge position error of all segments is lower than a preset threshold, or if the change in edge position error is lower than the threshold in several consecutive iterations, the iteration process terminates. After the iteration process converges, the electronic device 110 can output the final corrected mask pattern, which can more accurately reproduce the target design pattern in the actual imaging process.

[0066] In some embodiments, the electronic device 110 can perform optimized vectorized computation processing for different processor architectures and models. For example, the electronic device 110 can optimize the calculation of edge position errors and fragment aggregation operations based on the Single Instruction Multiple Data (SIMD) parallel computing mechanism. By selecting the corresponding math library according to the processor architecture and performing SIMD optimization, the electronic device 110 can significantly improve the execution efficiency of vectorized computation of edge position errors, thereby shortening the overall computation time and improving processing performance while ensuring computational accuracy.

[0067] In summary, the edge position error determination scheme of the embodiments of this disclosure introduces a gradient-based edge position error solution method, which dynamically utilizes the local gradient information of the lithographic simulation signal at the control point location to flexibly determine the update trend of the control points. In this way, the update of the control point location is no longer limited to the normal search path, thus significantly improving the convergence accuracy and stability of the boundary point search. Furthermore, by referring to the result of the previous update during the update process, update oscillations can be effectively mitigated and the convergence speed accelerated. The edge position error calculated based on the difference between the initial control point position and the target position drives optical proximity effect correction of the mask pattern. In this way, the correction process can achieve higher imaging accuracy and robustness while ensuring computational efficiency.

[0068] Figure 3 A flowchart of a process 300 for determining an edge position error according to some embodiments of the present disclosure is shown. In some embodiments, process 300 may be performed by, for example... Figure 1 The illustrated electronic device 110 performs this operation. It should be understood that process 300 may also include additional boxes not shown and / or some (or more) of the boxes shown may be omitted; the scope of this disclosure is not limited in this respect. The following is in conjunction with... Figure 1 The process 300 is described in detail.

[0069] like Figure 3 As shown, in block 310, electronic device 110 determines the degree of signal change of the photolithographic simulation signal for the control point in the mask pattern at the current position of the photolithographic simulation pattern.

[0070] In box 320, electronic device 110 updates the position of control point in photolithographic simulation pattern according to the degree of signal change of the photolithographic simulation signal of control point at the current position, so as to determine the target position of control point.

[0071] In box 330, electronic device 110 determines the edge position error of the control point based on the difference between the initial position and the target position of the control point.

[0072] In some embodiments, updating the position of the control point in the photolithographic simulation pattern includes updating the position of the control point in the photolithographic simulation pattern along the direction indicated by the degree of signal change.

[0073] In some embodiments, determining the degree of signal change includes: calculating the corresponding degree of signal change of the lithographic simulation signal at the current position in a first direction and a second direction, wherein the first direction is different from the second direction; and determining the degree of signal change of the lithographic simulation signal at the current position based on the corresponding degree of signal change in the first direction and the second direction.

[0074] In some embodiments, the degree of signal variation of the lithographic analog signal includes the gradient of the lithographic analog signal.

[0075] In some embodiments, updating the position of the control point according to the degree of signal change includes: updating the position of the control point in the photolithographic simulation pattern based on the gradient and a predetermined step size along the negative direction of the gradient.

[0076] In some embodiments, updating the position of the control point according to the degree of signal change includes: determining the velocity vector of the control point at the current position based on the gradient of the lithographic simulation signal of the control point at the current position and the historical update results of the control point's position; and updating the position of the control point along the negative direction of the velocity vector based on the velocity vector and a predetermined step size.

[0077] In some embodiments, the historical update result includes the velocity vector of the control point at the most recently updated position, and determining the velocity vector includes: weighting the velocity vector of the control point at the most recently updated position and the gradient of the lithographic simulation signal of the control point at the current position based on a predetermined weight; and determining the velocity vector of the control point at the current position based on the weighted result.

[0078] In some embodiments, determining the target location of the control point includes: determining the signal strength of the lithographic analog signal of the control point at the updated location; and determining the updated location as the target location of the control point in response to the signal strength meeting a signal strength threshold or the number of updates reaching a threshold number.

[0079] In some embodiments, the current position of the control point is represented by polar coordinates, and calculating the gradient of the control point at the current position includes: converting the coordinates of the control point at the current position from polar coordinates to Cartesian coordinates; calculating the lateral and longitudinal gradients of the lithographic simulation signal of the control point at the current position in Cartesian coordinates; and converting the lateral and longitudinal gradients into radial and angular gradients in polar coordinates.

[0080] In some embodiments, the mask pattern includes a plurality of segments, each of the plurality of segments including at least one control point, and the process 300 further includes: for each of the plurality of segments, determining an edge position error of the segment based on a corresponding edge position error of the at least one control point; and performing optical proximity correction on the mask pattern based on the corresponding edge position errors of the plurality of segments.

[0081] Figure 4 A block diagram is shown of an electronic device 400 in which one or more embodiments of the present disclosure may be implemented. The electronic device 400 may, for example, be used to implement... Figure 1 The electronic device 110 shown. It should be understood that, Figure 4 The electronic device 400 shown is merely exemplary and should not be construed as limiting the functionality and scope of the embodiments described herein.

[0082] like Figure 4 As shown, electronic device 400 is in the form of a general-purpose electronic device. Components of electronic device 400 may include, but are not limited to, one or more processors 410 or processing units, memory 420, storage device 430, one or more communication units 440, one or more input devices 450, and one or more output devices 460. The processing unit may be a physical or virtual processor and is capable of performing various processes according to programs stored in memory 420. In a multiprocessor system, multiple processing units execute computer-executable instructions in parallel to improve the parallel processing capability of electronic device 500.

[0083] Electronic device 400 typically includes multiple computer storage media. Such media can be any available media accessible to electronic device 400, including but not limited to volatile and non-volatile media, removable and non-removable media. Memory 420 can be volatile memory (e.g., registers, cache, random access memory (RAM)), non-volatile memory (e.g., read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory), or some combination thereof. Storage device 430 can be a removable or non-removable medium and can include machine-readable media, such as flash drives, disks, or any other media that can be used to store information and / or data (e.g., training data for training) and can be accessed within electronic device 400.

[0084] Electronic device 400 may further include additional removable / non-removable, volatile / non-volatile storage media. Although not explicitly stated... Figure 4 As shown, disk drives for reading from or writing to removable, non-volatile disks (e.g., "floppy disks") and optical disk drives for reading from or writing to removable, non-volatile optical disks can be provided. In these cases, each drive can be connected to a bus (not shown) via one or more data media interfaces. Memory 420 may include computer program product 425 having one or more program modules configured to perform various methods or actions of various embodiments of this disclosure.

[0085] The communication unit 440 enables communication with other electronic devices via a communication medium. Additionally, the functionality of the components of the electronic device 400 can be implemented using a single computing cluster or multiple computing machines capable of communicating via communication connections. Therefore, the electronic device 400 can operate in a networked environment using logical connections to one or more other servers, networked personal computers (PCs), or another network node.

[0086] Input device 450 can be one or more input devices, such as a mouse, keyboard, trackball, etc. Output device 460 can be one or more output devices, such as a monitor, speaker, printer, etc. Electronic device 400 can also communicate with one or more external devices (not shown) via communication unit 440 as needed. These external devices include storage devices, display devices, etc., and can communicate with one or more devices that enable user interaction with electronic device 400, or with any device that enables electronic device 400 to communicate with one or more other electronic devices (e.g., network card, modem, etc.). Such communication can be performed via input / output (I / O) interface (not shown).

[0087] According to an exemplary implementation of this disclosure, a computer-readable storage medium is provided that stores one or more computer instructions, wherein one or more computer instructions are executed by a processor to implement the methods described above.

[0088] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products implemented according to this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0089] These computer-readable program instructions can be provided to a processing unit of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processing unit of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner. Thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0090] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions that execute on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0091] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction, which contains one or more executable instructions for implementing the specified logical function. In some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0092] Various implementations of this disclosure have been described above. The foregoing description is exemplary and not exhaustive, nor is it limited to the disclosed implementations. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described implementations. The terminology used herein is chosen to best explain the principles, practical applications, or improvements to technology in the market, or to enable others skilled in the art to understand the implementations disclosed herein.

Claims

1. A method for determining edge position error, characterized in that, include: Determine the degree of signal change of the photolithographic simulation signal for the control points in the mask pattern at the current position of the photolithographic simulation pattern; The position of the control point in the lithographic simulation pattern is updated based on the degree of signal change of the lithographic simulation signal of the control point at the current position, so as to determine the target position of the control point; as well as The edge position error of the control point is determined based on the difference between the initial position and the target position of the control point.

2. The method for determining edge position error according to claim 1, characterized in that, Updating the position of the control points in the lithographic simulation pattern includes: The position of the control point in the photolithographic simulation pattern is updated along the direction indicated by the degree of signal change.

3. The method for determining edge position error according to claim 1 or 2, characterized in that, Determining the degree of signal change includes: Calculate the degree of signal change of the photolithographic analog signal at the current position in a first direction and a second direction, wherein the first direction is different from the second direction; and Based on the corresponding signal change levels in the first and second directions, the signal change level of the photolithographic simulation signal at the current position is determined.

4. The method for determining edge position error according to claim 1, characterized in that, The degree of signal variation of the photolithographic analog signal includes the gradient of the photolithographic analog signal.

5. The method for determining edge position error according to claim 4, characterized in that, Updating the position of the control point based on the degree of signal change includes: The position of the control point in the lithographic simulation pattern is updated along the negative direction of the gradient, based on the gradient and a predetermined step size.

6. The method for determining edge position error according to claim 4, characterized in that, Updating the position of the control point based on the degree of signal change includes: Based on the gradient of the photolithographic simulation signal of the control point at the current position and the historical update results of the control point's position, the velocity vector of the control point at the current position is determined; and The position of the control point is updated along the negative direction of the velocity vector, based on the velocity vector and a predetermined step size.

7. The method for determining edge position error according to claim 6, characterized in that, The historical update results include the velocity vector of the control point at the most recently updated position, and determining the velocity vector includes: Based on predetermined weights, the velocity vector of the control point at the most recently updated position and the gradient of the lithographic simulation signal of the control point at the current position are weighted; and Based on the weighted result, the velocity vector of the control point at its current position is determined.

8. The method for determining edge position error according to claim 1, characterized in that, Determining the target location of the control point includes: Determine the signal strength of the photolithographic analog signal at the updated position of the control point; and In response to the signal strength meeting a signal strength threshold or the number of updates reaching a threshold number, the updated position is determined as the target position of the control point.

9. The method for determining edge position error according to claim 1, characterized in that, The current position of the control point is represented in polar coordinates, and calculating the gradient of the control point at the current position includes: Convert the coordinates of the control point at its current position from polar coordinates to Cartesian coordinates; Calculate the lateral and longitudinal gradients of the lithographic simulation signal at the current position of the control point in the Cartesian coordinates; and The lateral gradient and the longitudinal gradient are converted into radial gradient and angular gradient in the polar coordinates.

10. The method for determining edge position error according to claim 1, characterized in that, The mask pattern comprises multiple segments, each segment comprising at least one of the control points, and the method further comprises: For each of the plurality of segments, the edge position error of that segment is determined based on the corresponding edge position error of at least one of the control points; and Optical proximity correction is performed on the mask pattern based on the corresponding edge position errors of the multiple segments.

11. An electronic device, characterized in that, include: At least one processing unit; as well as At least one memory, coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, the instructions causing the electronic device to perform the method according to any one of claims 1 to 10 when executed by the at least one processing unit.

12. A computer-readable storage medium, characterized in that, It stores a computer program thereon, characterized in that the computer program can be executed by a processor to implement the method according to any one of claims 1 to 10.

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