Scanning type exposure method and system adopting parallel digital micromirror array

Abstract

The invention discloses a scanning type exposure method and system adopting a parallel digital micromirror array, and relates to the technical field of photoetching exposure and maskless direct writing of mask.The scanning type exposure method comprises the steps that parallel digital micromirror initial mapping is established through a reference target exposure detection registration method; generating a block distortion field parameter table according to the initial mapping of the parallel digital micromirror, determining a micro-mark insertion position based on the block distortion field parameter table, and generating an expected coordinate; performing micro-mark exposure on the expected coordinate position, acquiring imaging data of the inserted micro-mark position, extracting an actual measurement coordinate from the imaging data of the micro-mark position, calculating a residual error by taking the expected coordinate and the actual measurement coordinate as an input difference, and writing the residual error into a residual error set; incremental fitting is carried out according to the residual set, the block distortion field parameter table is updated, and the exposure controller controls the parallel digital micromirror array to remap the pattern according to the updated block distortion field parameter table and triggers exposure. The method provided by the invention has better effects in coordinate mapping consistency and block parameter manageability.

Description

Technical Field

[0001] This invention relates to the field of photolithography exposure and maskless direct writing technology, specifically to a scanning exposure method and system using a parallel digital micromirror array. Background Technology

[0002] In the exposure architecture of parallel digital micromirror arrays and scanning motion, the mapping relationship of the pattern from the pixel coordinate system of the parallel digital micromirror array to the substrate coordinate system is often affected by multiple factors, resulting in deviations or changes over time.

[0003] Parallel arrays typically involve multiple subarrays working together to complete exposure. Assembly errors, relative orientation differences, differences in optical distortion distribution, and nonlinear distortion at the boundary of the projection coverage area between subarrays can easily lead to the difficulty in maintaining the geometric consistency of the output patterns of different subarrays on the substrate over a long period of time. During the scanning process, platform motion errors, speed fluctuations, thermal drift, and vibration disturbances introduce time-varying errors that vary with the scanning position, making it difficult to directly reuse the mapping parameters obtained from offline one-time calibration when running for a long time or across batch tasks.

[0004] In existing solutions, common practices often rely on offline detection and registration of benchmark targets to establish mapping relationships, or use coarse-grained global correction models for compensation. However, when faced with local distortion exhibiting blockiness, abrupt errors in boundary regions, and error accumulation during the scanning process, there is a lack of a closed-loop process that can continuously obtain correlated observation data during the scanning process, and collect observation deviations into residuals in a traceable manner, and then use them to incrementally update local mapping parameters.

[0005] If markers for observation are inserted during the scanning process, issues such as marker insertion location selection, reliability of marker imaging extraction, and consistent binding of observation data with distortion blocks and subarray indices need to be addressed. Otherwise, difficulties in engineering implementation may arise, such as observation data not being correctly attributed, uncontrollable parameter updates, or mismatch between update granularity and error distribution. Summary of the Invention

[0006] In view of the above-mentioned problems, the present invention is proposed.

[0007] Therefore, the technical problem solved by this invention is that existing parallel digital micromirror array scanning exposure methods have problems such as the mapping relationship from pixel coordinates to substrate coordinates relying on offline calibration and drifting with scanning position and time, difficulty in maintaining geometric consistency between subarrays and at strip boundaries, lack of traceable observation residual collection and incremental update mechanism, and how to form a residual set of expected coordinates and measured coordinates through micro-mark observation during the scanning process and drive the online update of the block distortion field parameter table, thereby realizing the closed-loop linkage between pattern remapping and exposure triggering.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a scanning exposure method using a parallel digital micromirror array, comprising establishing an initial mapping of the parallel digital micromirrors through a detection registration method using a reference target exposure.

[0009] A block distortion field parameter table is generated based on the initial mapping of the parallel digital micromirror. The micromark insertion position is determined based on the block distortion field parameter table, and the desired coordinates are generated.

[0010] Micro-marker exposure is performed at the desired coordinate position, imaging data of the micro-marker position is collected, measured coordinates are extracted from the micro-marker position imaging data, and the residual is calculated by using the desired coordinates and measured coordinates as input differences and written into the residual set.

[0011] Incremental fitting is performed based on the residual set to update the block distortion field parameter table. The exposure controller then controls the parallel digital micromirror array to remap the pattern according to the updated block distortion field parameter table and trigger the exposure.

[0012] As a preferred embodiment of the scanning exposure method using a parallel digital micromirror array described in this invention, the step of establishing the initial mapping of the parallel digital micromirror array includes calling the subarray number set of the parallel digital micromirror array and generating reference target exposure pattern data sequentially according to the subarray number set.

[0013] The baseline target exposure pattern data includes target feature points and feature line segments with pixel coordinates.

[0014] The coordinates of the benchmark target exposure pattern data in the parallel digital micromirror array pixel coordinate system are recorded as a set of target pixel coordinates.

[0015] Place the reference target in the alignment position, trigger the light source and perform reference target exposure, collect the target imaging data after exposure, and output the set of observation features corresponding to the target pixel coordinate set.

[0016] The set of observed features includes feature center coordinates, feature type identifiers, and feature confidence scores. Detection and registration are performed on the target pixel coordinate set and the set of observed features.

[0017] The detection and registration process includes solving the transformation from the subarray pixel coordinates to the substrate coordinate system and fitting the transformation parameters, using the fitting result as the initial mapping for the parallel digital micromirror.

[0018] As a preferred embodiment of the scanning exposure method using a parallel digital micromirror array described in this invention, the generation of the block distortion field parameter table includes determining the projection coverage range of the parallel digital micromirror array in the substrate coordinate system.

[0019] Multiple distortion blocks are divided within the projection coverage area, and a unique distortion block number is assigned to each distortion block. The local transformation parameters of the distortion blocks are calculated based on the initial mapping of the parallel digital micromirrors, and a block distortion field parameter table is constructed through the local transformation parameters.

[0020] The block distortion field parameter table includes the subarray number field, the distortion block number field, the local transformation parameter field, the parameter version field, and the update time field.

[0021] As a preferred embodiment of the scanning exposure method using a parallel digital micromirror array described in this invention, the step of determining the micromarker insertion position and generating the desired coordinates includes taking a block distortion field parameter table as input, combining the scanning direction parameter and the scanning strip range parameter of the scanning exposure, generating a candidate set of micromarker insertion positions within the scanning strip range, and performing position filtering on the candidate set of micromarker insertion positions.

[0022] The location filtering process includes using candidate locations located on the scan strip boundary line, the distortion block boundary line, and the projection coverage boundary line as a set of micromark insertion locations, and establishing a binding relationship between each micromark insertion location and the distortion block number and the subarray number.

[0023] Each insertion position is converted into the desired coordinates in the substrate coordinate system, and the desired coordinates are bound to the insertion position as a set of desired coordinate records.

[0024] As a preferred embodiment of the scanning exposure method using a parallel digital micromirror array described in this invention, the extraction of measured coordinates includes using the micromark insertion position and the bound distortion block number and subarray number in the micromark insertion position set as imaging acquisition indexes.

[0025] Micro-markers are exposed at the desired coordinate positions. Imaging data of the micro-marker positions is acquired by an imaging device and then collected into an imaging data record set according to the distortion block number and subarray number.

[0026] Micromark feature extraction is performed on each micromarked location imaging data in the imaging data record set.

[0027] Micro-marker feature extraction includes cropping the image region, normalizing grayscale, and suppressing noise based on the target feature points and feature line segments of the micro-marker exposure pattern, performing segmentation on the cropped image region, and outputting micro-marker candidate regions.

[0028] Perform geometric solution on the candidate region of micro-markers and output the feature center coordinates of the micro-markers as the measured coordinates.

[0029] When the candidate region for micro-markers is point-like, the geometric center of the connected region is used as the feature center coordinates. When the candidate region for micro-markers is line-segment-like, the coordinates of the midpoint of the line segment, the coordinates of the intersection of the fitted line of the line segment and the reference line are used as the feature center coordinates.

[0030] Establish a record correspondence between the measured coordinates and the corresponding micro-marker insertion position, distortion block number, and subarray number to form a set of measured coordinate records. Perform a validity judgment on each record in the set of measured coordinate records.

[0031] The validity assessment includes using the feature confidence level in the observed feature set as a reference to compare the consistency of the area, connectivity and related matching peak intensity of the micro-label candidate region.

[0032] If the consistency comparison condition is not met, the corresponding record will be marked as invalid and the acquisition of imaging data at the micro-marker position will be triggered again.

[0033] As a preferred embodiment of the scanning exposure method using a parallel digital micromirror array described in this invention, the differential calculation of residuals and writing them into the residual set includes aligning the desired coordinate record set and the measured coordinate record set according to the distortion block number, subarray number, and micromark insertion position to generate a coordinate aligned record set.

[0034] The coordinate alignment record includes the distorted block number, subarray number, expected coordinates, and measured coordinates.

[0035] Perform differential calculation on each coordinate-aligned record to output the residual, and write the residual, along with the valid marker, distorted block number, subarray number, and micro-marker insertion position, into the residual set.

[0036] As a preferred embodiment of the scanning exposure method using a parallel digital micromirror array described in this invention, the updating of the block distortion field parameter table includes taking the residual set as input and grouping the residual records according to the distortion block number field and the subarray number field to form a residual group set.

[0037] For each residual group set, read the residual records of the valid labeled fields and perform incremental fitting.

[0038] Incremental fitting includes parsing the local transformation parameter field into a parameter vector, forming a linearized solution relationship between the residual vector and the position of the insertion position in the substrate coordinate system and calculating the parameter increment, and updating the block distortion field parameter table according to the parameter increment.

[0039] The process of remapping the pattern and triggering exposure includes taking the updated block distortion field parameter table as input, retrieving the corresponding local transformation parameter fields by subarray number field and distortion block number field, performing coordinate remapping calculation on the pattern data to be exposed, and generating remapped pattern data.

[0040] The coordinate remapping calculation includes converting the substrate coordinate system pattern coordinates of the pattern data to be exposed into display coordinates in the parallel digital micromirror array pixel coordinate system through the local transformation parameter field.

[0041] After the remapping pattern data is sent to the parallel digital micromirror array and displayed, a trigger exposure command is generated by combining the scanning strip range parameters and the light source is triggered to perform exposure.

[0042] Another objective of this invention is to provide a scanning exposure system employing a parallel digital micromirror array (PDM array). This system can establish an initial mapping of the PDM array through detection registration based on a reference target exposure, construct a block distortion field parameter table according to the distortion block and subarray number, insert micromarkers within the scanning strip range to generate desired coordinates, acquire imaging data of the micromarker positions to extract measured coordinates and form a residual set by difference, perform incremental fitting based on the residual set to update the block distortion field parameter table, and drive pattern remapping and exposure triggering. This solves the problems of current parallel digital micromirror array scanning exposure technology, such as offline fixed mapping parameters, inability to continuously collect and update errors during the scanning process, and difficulty in correcting geometric deviations at the subarray and strip boundaries.

[0043] As a preferred embodiment of the scanning exposure system using a parallel digital micromirror array described in this invention, it includes: an initial mapping establishment module, a block distortion field parameter table generation and desired coordinate generation module, a micro-marker exposure acquisition and residual set generation module, and an incremental fitting update and remapping triggered exposure module.

[0044] The initial mapping establishment module is used to establish the initial mapping of the parallel digital micromirror through the detection registration method of the reference target exposure.

[0045] The block distortion field parameter table generation and desired coordinate generation module is used to generate a block distortion field parameter table based on the initial mapping of the parallel digital micromirror, determine the micro-marker insertion position based on the block distortion field parameter table, and generate desired coordinates.

[0046] The micro-marker exposure acquisition and residual set generation module is used to perform micro-marker exposure on the desired coordinate position, acquire imaging data of the micro-marker position, extract the measured coordinates from the micro-marker position imaging data, calculate the residual by using the desired coordinates and the measured coordinates as input differences, and write the residuals into the residual set.

[0047] The incremental fitting update and remapping trigger exposure module is used to perform incremental fitting based on the residual set, update the block distortion field parameter table, and the exposure controller controls the parallel digital micromirror array to remap the pattern and trigger exposure based on the updated block distortion field parameter table.

[0048] Another object of the present invention is to provide a scanning exposure apparatus employing a parallel digital micromirror array, comprising a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement a scanning exposure method employing a parallel digital micromirror array.

[0049] Another object of the present invention is to provide a scanning exposure storage medium employing a parallel digital micromirror array, wherein a computer program is stored thereon, and when the computer program is executed by a processor, the steps of a scanning exposure method employing a parallel digital micromirror array are implemented.

[0050] The beneficial effects of this invention are as follows: The scanning exposure method using a parallel digital micromirror array (PDM array) provided by this invention establishes an initial mapping of the PDM array through a detection and registration step of the reference target exposure. This enables the acquisition of the transformation relationship from the pixel coordinate system of the PDM array to the substrate coordinate system, providing a unified coordinate reference for subsequent parameter table construction. This ensures that exposure control and detection feedback have consistent coordinate references, achieving the effect that the mapping relationship can be obtained and used for subsequent closed-loop calculations. Furthermore, the step of generating a block-based distortion field parameter table based on the initial mapping of the PDM array organizes local transformation parameters according to the distortion block number and subarray number. This allows the distortion distribution to be expressed in an indexable data structure and supports local calculations, thus enabling block-level manageability of coordinate conversion within the scanning strip area. This achieves the effect of traceable, callable, and locally updated parameter organization. Finally, by determining the micro-marker insertion position and generating the desired coordinates during the scanning process, and then acquiring imaging data at the micro-marker position... The process involves extracting measured coordinates and differentially writing them into the residual set. This allows process observations to be bound to the distortion block number and subarray number in the form of desired coordinates, measured coordinates, and residuals. This forms process data input that can be used for fitting and updating, enabling structured aggregation of deviations during the scanning process. This achieves the effect of alignable and groupable residual data that can directly drive subsequent incremental fitting. By incrementally fitting and updating the block distortion field parameter table based on the residual set, and then remapping the pattern and triggering exposure, local transformation parameters are iteratively updated during the scanning process and fed back to the exposure pattern coordinate remapping. This enables the exposure controller to complete closed-loop linkage of acquisition, calculation, updating, and remapping under the same index system, thus maintaining continuous operation of the scanning exposure process. This achieves the effect of an implementable online correction mechanism and a complete closed-loop link. This invention achieves better results in terms of coordinate mapping consistency, block parameter manageability, and closed-loop linkage during the scanning process. Attached Figure Description

[0051] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 This is an overall flowchart of a scanning exposure method using a parallel digital micromirror array, provided in Embodiment 1 of the present invention. Detailed Implementation

[0053] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0054] Example 1, referring to Figure 1 As an embodiment of the present invention, a scanning exposure method using a parallel digital micromirror array is provided, comprising: S1: Establish the initial mapping of parallel digital micromirrors through the detection registration method of exposure to the reference target.

[0055] The set of subarray numbers of the parallel digital micromirror array is invoked, and the exposure pattern data of the reference target is generated sequentially according to the set of subarray numbers.

[0056] The baseline target exposure pattern data includes target feature points and feature line segments with pixel coordinates.

[0057] The coordinates of the benchmark target exposure pattern data in the parallel digital micromirror array pixel coordinate system are recorded as a set of target pixel coordinates.

[0058] Place the reference target in the alignment position, trigger the light source and perform reference target exposure, collect the target imaging data after exposure, and output the set of observation features corresponding to the target pixel coordinate set.

[0059] The set of observed features includes feature center coordinates, feature type identifiers, and feature confidence scores. Detection and registration are performed on the target pixel coordinate set and the set of observed features.

[0060] The detection and registration process includes solving the transformation from the subarray pixel coordinates to the substrate coordinate system and fitting the transformation parameters, using the fitting result as the initial mapping for the parallel digital micromirror.

[0061] A preferred approach to using the fitting results as the initial mapping for parallel digital micromirrors is as follows:

[0062] in, This represents the coordinate vector in the substrate coordinate system. This represents the coordinate vector in the pixel coordinate system of a parallel digital micromirror array. Indicates the subarray number. Subarray The linear mapping parameter matrix, Subarray The translation vector.

[0063] Furthermore, the projection coverage of the parallel digital micromirror array in the substrate coordinate system was determined.

[0064] The projection coverage area is divided into multiple distortion blocks, and each distortion block is assigned a unique distortion block number.

[0065] The local transformation parameters of the distortion block are calculated based on the initial mapping of the parallel digital micromirror, and a block distortion field parameter table is constructed using the local transformation parameters.

[0066] The block distortion field parameter table includes the subarray number field, distortion block number field, local transformation parameter field, parameter version field, and update time field.

[0067] S2: Generate a block distortion field parameter table based on the initial mapping of the parallel digital micromirror, determine the micro-marker insertion position based on the block distortion field parameter table, and generate the desired coordinates.

[0068] Using the block distortion field parameter table as input, and combining the scanning direction parameters and scanning strip range parameters of the scanning exposure, a candidate set of micromarker insertion positions is generated within the scanning strip range.

[0069] Perform position filtering on the candidate set of micromark insertion positions.

[0070] The location filtering process includes using candidate locations located on the scan strip boundary line, the distortion block boundary line, and the projection coverage boundary line as a set of micromark insertion locations, and establishing a binding relationship between each micromark insertion location and the distortion block number and the subarray number.

[0071] Each insertion position is converted into the desired coordinates in the substrate coordinate system, and the desired coordinates are bound to the insertion position as a set of desired coordinate records.

[0072] A preferred method for converting to the desired coordinates in the substrate coordinate system is as follows:

[0073] in, Indicates the micromark insertion position index. Indicates the first The expected coordinates of each micro-marker Indicates the first The pixel coordinates of the insertion position of each micro-marker This indicates a desired marker, used only for differentiation. This indicates the insertion position marker, used only for distinction. Indicates the first The subarray number is bound to the insertion position of each micro-marker. Indicates the first The distorted block number is bound to the insertion position of each micro-mark. In the block distortion field parameter table, the key is (subarray number field) distorted block number field The simplified expression of the local transformation parameter field corresponding to ).

[0074] S3: Expose the desired coordinate position with micro-markers, collect imaging data of the micro-marker position, extract the measured coordinates from the micro-marker position imaging data, use the desired coordinates and measured coordinates as input to calculate the residual and write it into the residual set.

[0075] The imaging acquisition index is based on the micromark insertion position and the bound distortion block number and subarray number in the micromark insertion position set.

[0076] Micro-markers are exposed at the desired coordinate positions. Imaging data of the micro-marker positions is acquired by an imaging device and then collected into an imaging data record set according to the distortion block number and subarray number.

[0077] Micromark feature extraction is performed on each micromarked location imaging data in the imaging data record set.

[0078] Micro-marker feature extraction includes cropping the image region, normalizing grayscale, and suppressing noise based on the target feature points and feature line segments of the micro-marker exposure pattern, performing segmentation on the cropped image region, and outputting micro-marker candidate regions.

[0079] Perform geometric solution on the candidate region of micro-markers and output the feature center coordinates of the micro-markers as the measured coordinates.

[0080] When the candidate region for micro-labels is point-like, the geometric center of the connected region is used as the coordinate of the feature center.

[0081] When the candidate region for micro-markers is a line segment, the coordinates of the midpoint of the line segment, the coordinates of the intersection of the fitted line of the line segment and the reference line are used as the coordinates of the feature center.

[0082] Establish a record correspondence between the measured coordinates and the corresponding micro-marker insertion position, distortion block number, and subarray number to form a set of measured coordinate records.

[0083] Perform a validity check on each record in the set of measured coordinate records.

[0084] The validity assessment includes using the feature confidence level in the observed feature set as a reference to compare the consistency of the area, connectivity and related matching peak intensity of the micro-label candidate region.

[0085] If the consistency comparison condition is not met, the corresponding record will be marked as invalid and the acquisition of imaging data at the micro-marker position will be triggered again.

[0086] Furthermore, the expected coordinate record set and the measured coordinate record set are aligned according to the distortion block number, subarray number, and micromark insertion position to generate a coordinate aligned record set.

[0087] The coordinate alignment record includes the distorted block number, subarray number, expected coordinates, and measured coordinates.

[0088] Perform differential calculation on each coordinate-aligned record to output the residual, and write the residual, along with the valid marker, distorted block number, subarray number, and micro-marker insertion position, into the residual set.

[0089] A preferred approach for performing differential calculations to output residuals is as follows:

[0090] in, Indicates the first The residual vector of the aligned records, Indicates the first Valid marker fields for each record Indicates the first Measured coordinates of each micro-marker.

[0091] S4: Incremental fitting is performed based on the residual set to update the block distortion field parameter table. The exposure controller controls the parallel digital micromirror array to remap the pattern according to the updated block distortion field parameter table and trigger the exposure.

[0092] Using the residual set as input, the residual records are grouped according to the distortion block number field and the subarray number field to form a residual group set.

[0093] For each residual group set, read the residual records of the valid labeled fields and perform incremental fitting.

[0094] Incremental fitting includes parsing the local transformation parameter field into a parameter vector, forming a linearized solution relationship between the residual vector and the position of the insertion position in the substrate coordinate system and calculating the parameter increment, and updating the block distortion field parameter table according to the parameter increment.

[0095] A preferred approach for updating the block distortion field parameter table based on parameter increments is as follows:

[0096] in, This indicates the local transformation parameter field. Indicates the update symbol. Indicates the incremental update coefficient. This represents an operator that performs component-wise averaging on vectors within a set. This represents the set selection expression, specifically: selecting from the residual set that satisfy the condition of belonging to a subarray. , distortion block A residual vector that is effectively labeled as 1.

[0097] The process of remapping the pattern and triggering exposure includes taking the updated block distortion field parameter table as input, retrieving the corresponding local transformation parameter fields by subarray number field and distortion block number field, performing coordinate remapping calculation on the pattern data to be exposed, and generating remapped pattern data.

[0098] The coordinate remapping calculation includes converting the substrate coordinate system pattern coordinates of the pattern data to be exposed into display coordinates in the parallel digital micromirror array pixel coordinate system through the local transformation parameter field.

[0099] A preferred method for generating and displaying coordinates is:

[0100] in, Indicates the coordinate index of the pattern to be exposed. Indicates the first The display coordinates are obtained by remapping the pattern points. Indicates the first The subarray number to which each pattern point belongs. Indicates the first The distortion block number to which each pattern point belongs. Representation matrix The inverse matrix, This indicates a display marker used for differentiation. These are pattern markings used for differentiation.

[0101] After the remapping pattern data is sent to the parallel digital micromirror array and displayed, a trigger exposure command is generated by combining the scanning strip range parameters and the light source is triggered to perform exposure.

[0102] Example 2 is an embodiment of the present invention, which provides a scanning exposure method using a parallel digital micromirror array. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0103] First, a comparative experiment was conducted using a scanning exposure platform employing a parallel digital micromirror array (PDMI). The platform comprises a parallel digital micromirror array, specifically: a parallel projection unit consisting of four subarrays, a 405nm exposure light source, a scanning motion platform, a reference target, an imaging device, and an exposure controller.

[0104] The test substrate is a 6-inch glass substrate, with positive photoresist spin-coated on the surface and soft-baked to ensure that the exposed pattern has detectable edges and contrast.

[0105] To ensure the objectivity of the comparison, the six groups of test subjects were executed on the same hardware platform, with the same light source power, the same scanning strip range, and the same scanning speed range. The differences were only in the mapping establishment, distortion field management, micro-marker observation, and parameter update strategy.

[0106] Among them, comparison A uses offline calibration once without updating parameters, comparison B uses offline calibration and performs recalibration every 30 minutes, and comparison C uses global online calibration but does not perform block management.

[0107] In this invention, D, E, and F all use a block-based distortion field parameter table and insert micromarkers during the scanning process to form a residual closed loop. The difference lies in the different micromarker insertion densities.

[0108] The exposure controller calls the subarray number set and generates the reference target exposure pattern data in sequence according to the number. The pattern data contains target feature points and feature line segments with pixel coordinates and records them as a target pixel coordinate set.

[0109] The reference target is then placed in the alignment position, the light source is triggered to perform reference target exposure, the imaging device collects the target imaging data after exposure, and outputs the observation feature set corresponding to the target pixel coordinate set. The observation feature set records the feature center coordinates, feature type identifier and feature confidence level.

[0110] The exposure controller performs detection registration on the target pixel coordinate set and the observation feature set, completes the transformation solution from the subarray pixel coordinates to the substrate coordinate system, and fits the transformation parameters. The fitting result is used as the initial mapping of the parallel digital micromirror.

[0111] Subsequently, the exposure controller determines the projection coverage of the parallel digital micromirror array in the substrate coordinate system, divides the area into distortion blocks, and assigns a distortion block number to each distortion block. Based on the initial mapping of the parallel digital micromirrors, the local transformation parameters of each distortion block are calculated, and a block distortion field parameter table is constructed. The parameter table includes a subarray number field, a distortion block number field, a local transformation parameter field, a parameter version field, and an update time field.

[0112] The exposure controller takes the block distortion field parameter table as input, combines the scanning direction parameter and the scanning strip range parameter, generates a candidate set of micromarker insertion positions within the scanning strip range, and performs position filtering: it prioritizes the selection of candidate positions located near the scanning strip boundary line, the distortion block boundary line, and the projection coverage range boundary line as the micromarker insertion position set.

[0113] At the same time, the insertion position of each micro-marker is bound to the distortion block number and subarray number to ensure that subsequent observation data can be directly assigned to the corresponding distortion block and subarray.

[0114] Subsequently, the exposure controller maps the micro-mark insertion position to the desired coordinates in the substrate coordinate system, and binds the desired coordinates to the insertion position to form a set of desired coordinate records.

[0115] The exposure controller performs micro-marker exposure at the desired coordinate positions. The imaging device acquires imaging data at the micro-marker insertion positions and aggregates them into an imaging data record set according to the distortion block number and subarray number. For each imaging data, micro-marker feature extraction is performed: based on the feature type identifier of the micro-marker exposure pattern, the image is cropped, grayscale normalized, and noise suppressed. Within the cropped area, segmentation is performed to obtain micro-marker candidate regions.

[0116] Next, geometric solutions are performed on the candidate regions, and the feature center coordinates of the micro-markers are output as the measured coordinates. Then, a record correspondence is established between the measured coordinates and the micro-marker insertion position, distortion block number, and subarray number to form a set of measured coordinate records. The validity of each record is judged. Using the feature confidence in the observed feature set as a reference, the area, connectivity, and matching strength of the candidate regions are compared for consistency. Records that do not meet the conditions are marked as invalid and trigger a re-acquisition.

[0117] After the validity screening is completed, the expected coordinate record set and the measured coordinate record set are aligned according to the distortion block number, subarray number and micromark insertion position to obtain the coordinate aligned record set. The residual is obtained by performing difference on each aligned record, and the residual, along with the valid marker, distortion block number, subarray number and micromark insertion position, is written into the residual set.

[0118] The exposure controller takes the residual set as input, groups the residual records according to the distortion block number field and the subarray number field to form a residual group set, reads only the residual records corresponding to the valid label fields, performs incremental fitting and calculates the parameter increment, and then updates the local transformation parameter field in the block distortion field parameter table. At the same time, it refreshes the parameter version field and update time field according to the update rules.

[0119] Subsequently, the exposure controller takes the updated block distortion field parameter table as input, retrieves the local transformation parameters of the corresponding distortion block and subarray, performs coordinate remapping calculation on the pattern data to be exposed, generates remapped pattern data, and sends it to the parallel digital micromirror array.

[0120] After the array is displayed, the exposure trigger command is generated by combining the scan strip range parameters and the light source is triggered to perform exposure, thus forming a continuous closed-loop operation process of observation, residual, incremental fitting, parameter table update, remapping, and exposure. The experimental data are shown in Table 1.

[0121] Table 1 Experimental Data

[0122] As can be seen from the data table, the six groups of test subjects operated under the same number of subarrays, the same projection coverage, the same scan strip range, and the same scan direction parameters. The differences were mainly reflected in the granularity of distortion field management, the micro-label insertion density, and the parameter update mechanism.

[0123] First, baseline target registration The six groups of objects are basically consistent, specifically: baseline target registration. The distance between the six groups of objects is approximately 2.03–2.05 µm, indicating that the detection registration mapping originated from a common starting point and did not artificially amplify the initial advantages of the invention.

[0124] Therefore, the differences in subsequent indicators mainly come from the online observation and continuous correction process during scanning, rather than the differences in initial registration accuracy.

[0125] Secondly, after 2 hours, the geometric drift RMS reached 3.90µm in comparison A, decreased to 2.70µm in comparison B after 30 minutes of recalibration, and further decreased to 2.10µm in comparison C after global online correction, while the RMS of the present invention decreased to 1.20, 0.95 and 0.85µm in D, E and F respectively.

[0126] This set of data has a clear causal relationship: in contrast A, the lack of process updates leads to drift accumulation, while in contrast B, the reliance on discrete scaling means that drift will still accumulate within the scaling interval.

[0127] Although C introduces online correction, it does not include a block-based distortion field parameter table. Therefore, the correction mainly absorbs errors at the global scale, which is insufficient when facing local nonlinear distortions and boundary errors.

[0128] This invention uses the distortion block number and subarray number for indexing, collects the residual into the local block and performs incremental fitting update, so that the drift is continuously absorbed and fed back into the coordinate remapping in a closed loop during the scanning process, thus maintaining a lower drift RMS under long-term operation.

[0129] The strip splicing error RMS and the subarray deviation P95 directly reflect the geometric consistency between the scan strip boundary and the subarray splicing point. Compared with A, the strip splicing error reaches 4.80µm and the subarray deviation P95 reaches 5.10µm, indicating that offline calibration in one step is difficult to cover the entire scan process and boundary effects.

[0130] Although B has a recalibrated strip, the strip splicing error is still 3.20µm. In contrast, C, after introducing online correction, has reduced the error to 2.40µm and 2.90µm, indicating that global correction can improve the overall deviation but is still limited by local distortion.

[0131] In this invention, the values ​​of D, E, and F are further reduced to 1.40, 1.10, and 0.90 µm and 1.60, 1.20, and 1.00 µm, respectively. Furthermore, as the micromark insertion interval decreases from 6 mm to 3 mm and the number of micromarks per strip increases from 55 to 110, the error shows an interpretable decreasing trend. This indicates that the increased micromark observation density can provide more sufficient sample support for incremental fitting within the distortion block, making the local transformation parameters of the block distortion field parameter table updated more timely and closer to the actual error distribution.

[0132] Meanwhile, the residual RMS within the distortion block gradually decreased from 3.60µm in Comparison A to 0.75µm in F of this invention, consistent with the structural difference of increasing the number of distortion blocks from 1 to 96, demonstrating the ability of block management to express and absorb nonlinear distortion.

[0133] Furthermore, the effective labeling rate remained above 96% in all groups, with the present invention group being slightly higher, specifically 97.3%–97.8%. Combined with the number of re-acquisitions, it can be seen that the closed-loop process did not introduce an uncontrollable acquisition failure rate and remained at a level that could be engineered.

[0134] It should be noted that the coordinate remapping calculation delay of this invention increases with the increase of the marker density, specifically: 22→34ms / strip, while the scanning throughput decreases slightly, specifically: 6.4→6.0 strips. This is a reasonable cost of introducing residual set, incremental fitting, parameter table update, and remapping closed-loop calculation during the scanning process.

[0135] However, the cost is matched by a significant improvement in the error metrics, and the number of parameter version updates increases with the label density, specifically from 6 to 14 times per band. This indicates that the update action is not a fixed-frequency hard trigger, but rather a finer-grained process correction that can be achieved as effective residual samples are supplied.

[0136] In summary, the data table demonstrates from multiple dimensions, including drift control, strip stitching, subarray consistency, intra-block residual convergence, label validity, and computational cost, that this invention, through a binding and aggregation mechanism between the block distortion field parameter table and the micro-label residual set, and a linkage mechanism between incremental fitting update and exposure remapping based on the residual set, forms a continuously operable online geometric distortion field calibration and scanning process correction workflow. Therefore, compared with existing offline calibration, periodic recalibration, or global online correction schemes, it demonstrates a more creative and implementable closed-loop process organization method and engineering feasibility.

[0137] Example 3, an embodiment of the present invention, provides a scanning exposure system using a parallel digital micromirror array, including an initial mapping establishment module, a block distortion field parameter table generation and desired coordinate generation module, a micro-marker exposure acquisition and residual set generation module, and an incremental fitting update and remapping triggered exposure module.

[0138] The initial mapping establishment module is used to establish the initial mapping of the parallel digital micromirror through the detection registration method of the benchmark target exposure.

[0139] The module for generating block distortion field parameter tables and desired coordinates is used to generate block distortion field parameter tables based on the initial mapping of parallel digital micromirrors, determine the micro-marker insertion positions based on the block distortion field parameter tables, and generate desired coordinates.

[0140] The micro-marker exposure acquisition and residual set generation module is used to perform micro-marker exposure at the desired coordinate position, acquire imaging data of the micro-marker position, extract the measured coordinates from the micro-marker position imaging data, calculate the residual by using the desired coordinates and measured coordinates as input, and write the residual into the residual set.

[0141] The incremental fitting update and remapping trigger exposure module is used to perform incremental fitting based on the residual set, update the block distortion field parameter table, and the exposure controller controls the parallel digital micromirror array to remap the pattern and trigger exposure based on the updated block distortion field parameter table.

[0142] This embodiment also provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the scanning exposure method using a parallel digital micromirror array as proposed in the above embodiment.

[0143] This embodiment also provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it implements the scanning exposure method using a parallel digital micromirror array as proposed in the above embodiments.

[0144] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0145] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-including system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0146] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0147] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0148] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A scanning exposure method using a parallel digital micromirror array, characterized in that, include: Initial mapping of parallel digital micromirrors is established using a detection registration method based on exposure to a benchmark target. A block distortion field parameter table is generated based on the initial mapping of the parallel digital micromirror. The micromark insertion position is determined based on the block distortion field parameter table, and the desired coordinates are generated. Micro-mark exposure is performed at the desired coordinate position, imaging data of the micro-mark position is collected, the measured coordinates are extracted from the micro-mark position imaging data, the residual is calculated by using the desired coordinates and the measured coordinates as input differences and written into the residual set; Incremental fitting is performed based on the residual set to update the block distortion field parameter table. The exposure controller then controls the parallel digital micromirror array to remap the pattern according to the updated block distortion field parameter table and trigger the exposure.

2. The scanning exposure method using a parallel digital micromirror array as described in claim 1, characterized in that: The establishment of the initial mapping for the parallel digital micromirror includes... The set of subarray numbers of the parallel digital micromirror array is called, and the exposure pattern data of the reference target is generated sequentially according to the set of subarray numbers; The baseline target exposure pattern data includes target feature points and feature line segments with pixel coordinates. The coordinates of the baseline target exposure pattern data in the parallel digital micromirror array pixel coordinate system are recorded as a set of target pixel coordinates. Place the reference target in the alignment position, trigger the light source, and perform reference target exposure; Collect target imaging data after exposure and output the set of observation features corresponding to the target pixel coordinate set; The set of observed features includes the coordinates of the feature center, the feature type identifier, and the feature confidence level. Perform detection registration on the target pixel coordinate set and the observed feature set; The detection and registration process includes solving the transformation from the subarray pixel coordinates to the substrate coordinate system and fitting the transformation parameters, using the fitting result as the initial mapping for the parallel digital micromirror.

3. The scanning exposure method using a parallel digital micromirror array as described in claim 1 or 2, characterized in that: The generated block distortion field parameter table includes... Determine the projection coverage of the parallel digital micromirror array in the substrate coordinate system; Divide the projection coverage area into multiple distortion blocks and assign a unique distortion block number to each distortion block; Calculate local transformation parameters of the distortion block based on the initial mapping of parallel digital micromirrors; A block-based distortion field parameter table is constructed using local transformation parameters; The block distortion field parameter table includes the subarray number field, the distortion block number field, the local transformation parameter field, the parameter version field, and the update time field.

4. The scanning exposure method using a parallel digital micromirror array as described in claim 3, characterized in that: The process of determining the micro-marker insertion position and generating the desired coordinates includes, Using the block distortion field parameter table as input, and combining the scanning direction parameter and scanning strip range parameter of the scanning exposure, a candidate set of micromark insertion positions is generated within the scanning strip range. Perform position filtering on the candidate set of micromark insertion positions; The location filtering includes taking the candidate locations located on the boundary lines of the scan strip, the boundary lines of the distortion block, and the boundary lines of the projection coverage area as a set of micro-marker insertion locations, and establishing a binding relationship between each micro-marker insertion location and the distortion block number and the subarray number; Convert each insertion position into the desired coordinates in the substrate coordinate system; The desired coordinates are bound to the insertion position as a set of desired coordinate records.

5. The scanning exposure method using a parallel digital micromirror array as described in claim 1, 2, or 4, characterized in that: The extraction of measured coordinates includes, The imaging acquisition index is based on the micro-marker insertion position and the bound distortion block number and subarray number in the micro-marker insertion position set. Micro-markers are exposed at the desired coordinate positions. Imaging data of the micro-marker positions are acquired by an imaging device and the micro-marker positions are collected into an imaging data record set according to the distortion block number and sub-array number. Micromark feature extraction is performed on each micromarked location imaging data in the imaging data record set; Micro-marker feature extraction includes cropping the image, normalizing the grayscale, and suppressing noise based on the feature type identifiers of the target feature points and feature line segments of the micro-marker exposure pattern; performing segmentation on the cropped image region; and outputting micro-marker candidate regions. Perform geometric solution on the candidate region of micro-marker and output the feature center coordinates of the micro-marker as the measured coordinates; When the candidate region of the micro-label is point-like, the geometric center of the connected region is used as the coordinate of the feature center. When the candidate region for micro-markers is line segment, the coordinates of the midpoint of the line segment, the coordinates of the intersection of the fitted line of the line segment and the reference line are used as the coordinates of the feature center. Establish a record correspondence between the measured coordinates and the corresponding micro-marker insertion positions, distortion block numbers, and subarray numbers to form a set of measured coordinate records; Perform a validity check on each record in the set of measured coordinate records; The validity assessment includes using the feature confidence scores in the observed feature set as a reference to compare the consistency of the area, connectivity, and relevant matching peak intensity of the micro-label candidate region. If the consistency comparison condition is not met, the corresponding record will be marked as invalid and the acquisition of imaging data at the micro-marker position will be triggered again.

6. The scanning exposure method using a parallel digital micromirror array as described in claim 5, characterized in that: The differential calculation of residuals and writing them into the residual set includes, The expected coordinate record set and the measured coordinate record set are aligned according to the distortion block number, subarray number and micromark insertion position to generate a coordinate aligned record set. The coordinate alignment record includes the distorted block number, subarray number, expected coordinates, and measured coordinates; Perform differential calculation on each coordinate-aligned record to output the residual, and write the residual, along with the valid marker, distorted block number, subarray number, and micro-marker insertion position, into the residual set.

7. The scanning exposure method using a parallel digital micromirror array as described in claim 1, 2, 4, or 6, characterized in that: The updated block distortion field parameter table includes... Using the residual set as input, the residual records are grouped according to the distortion block number field and the subarray number field to form a residual group set; For each residual group set, read the residual records with valid labeled fields and perform incremental fitting; Incremental fitting includes parsing the local transformation parameter field into a parameter vector, forming a linearized solution relationship between the residual vector and the position of the insertion position in the substrate coordinate system and calculating the parameter increment, and updating the block distortion field parameter table according to the parameter increment. The process of remapping the pattern and triggering exposure includes taking the updated block distortion field parameter table as input, retrieving the corresponding local transformation parameter field by subarray number field and distortion block number field, performing coordinate remapping calculation on the pattern data to be exposed, and generating remapped pattern data. The coordinate remapping calculation includes converting the substrate coordinate system pattern coordinates of the pattern data to be exposed into display coordinates in the parallel digital micromirror array pixel coordinate system through the local transformation parameter field. After the remapping pattern data is sent to the parallel digital micromirror array and displayed, a trigger exposure command is generated by combining the scanning strip range parameters and the light source is triggered to perform exposure.

8. A scanning exposure system employing a parallel digital micromirror array, using the scanning exposure method employing a parallel digital micromirror array as described in any one of claims 1 to 7, characterized in that: It includes an initial mapping establishment module, a block distortion field parameter table generation and expected coordinate generation module, a micro-marker exposure acquisition and residual set generation module, and an incremental fitting update and remapping triggered exposure module. The initial mapping establishment module is used to establish the initial mapping of the parallel digital micromirror using the detection registration method of the reference target exposure; The block distortion field parameter table generation and desired coordinate generation module is used to generate a block distortion field parameter table based on the initial mapping of the parallel digital micromirror, determine the micro-marker insertion position based on the block distortion field parameter table, and generate the desired coordinates. The micro-marker exposure acquisition and residual set generation module is used to perform micro-marker exposure on the desired coordinate position, acquire imaging data of the inserted micro-marker position, extract the measured coordinates from the micro-marker position imaging data, use the desired coordinates and the measured coordinates as input differences to calculate the residuals and write them into the residual set. The incremental fitting update and remapping trigger exposure module is used to perform incremental fitting based on the residual set, update the block distortion field parameter table, and the exposure controller controls the parallel digital micromirror array to remap the pattern and trigger exposure based on the updated block distortion field parameter table.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the scanning exposure method using a parallel digital micromirror array as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the scanning exposure method using a parallel digital micromirror array as described in any one of claims 1 to 7.

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