Write-through photoetching machine, exposure synchronization diagnosis method thereof and signal synchronization processing unit

Abstract

The invention discloses a write-through lithography machine and an exposure synchronization diagnosis method and a signal synchronization processing unit thereof, and the write-through lithography machine exposure synchronization diagnosis method comprises the following steps: in an exposure process, obtaining a first position synchronization signal when the movement displacement of a motion platform reaches a theoretical trigger interval, and obtaining a second position synchronization signal when the movement displacement reaches a theoretical trigger interval; acquiring the physical position of the motion platform; calculating a calculation position of the motion platform according to the first position synchronization signal; and when the position deviation between the physical position and the calculation position is greater than a position deviation threshold value, performing early warning processing. According to the method provided by the invention, diagnosis and timely early warning of the abnormity of the position synchronization signal in the exposure process are realized, and the abnormal deviation between the calculated position of the motion platform and the actual physical position of the motion platform obtained based on the position synchronization signal can be found in time; therefore, the risks of exposure position offset, pattern distortion and the like caused by abnormal position synchronization are reduced, and the reliability of the exposure process is improved.

Description

Technical Field

[0001] This invention relates to the field of lithography technology, and in particular to a direct-write lithography machine and its exposure synchronization diagnosis method and signal synchronization processing unit. Background Technology

[0002] With the expanding application of direct-write lithography technology, centered on digital micromirror devices (DMDs), in fields such as printed circuit board and semiconductor device manufacturing, higher demands are being placed on the exposure accuracy and production efficiency of direct-write lithography machines. During exposure, the motion platform moves in a continuous scanning manner and generates position synchronization signals according to a set trigger interval to control the refresh of the exposure image and the laser exposure timing. Therefore, the position synchronization accuracy directly affects the accuracy of the exposure position and the final pattern quality. Accurately reflecting the position state of the motion platform during exposure is a crucial foundation for ensuring the exposure quality of direct-write lithography machines.

[0003] In existing technologies, one approach is to directly calculate the position of the motion platform based on the feedback signal from the grating ruler and then transmit this position information to the exposure processing unit. Another approach is for the motion platform driver to output a position synchronization signal when the platform moves to a preset trigger interval and then transmit this synchronization signal to the exposure control module. However, both of these approaches generally employ an open-loop transmission method for the position synchronization signal, lacking a means to monitor the consistency between the position synchronization signal and the actual physical position of the motion platform during the exposure process. When the position synchronization signal is abnormal, drifts, or distorted, the system struggles to detect and address it in a timely manner, potentially leading to continuous exposure operations during the exposure process. This can cause problems such as exposure position offset and image distortion, increasing the risk of product scrap and reducing the reliability of the exposure process. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one objective of this invention is to propose an exposure synchronization diagnostic method for a direct-write lithography machine. This method enables the diagnosis and timely warning of abnormalities in the position synchronization signal during the exposure process. It can promptly detect abnormal deviations between the calculated position of the motion platform obtained based on the position synchronization signal and the actual physical position of the motion platform, thereby reducing the risks of exposure position offset and pattern distortion caused by abnormal position synchronization and improving the reliability of the exposure process.

[0005] The second objective of this invention is to provide a signal synchronization processing unit.

[0006] The third objective of this invention is to provide a direct-write lithography machine.

[0007] To achieve the above objectives, the direct-write lithography machine exposure synchronization diagnosis method according to a first aspect of the present invention includes: during the exposure process, acquiring a first position synchronization signal when the displacement of the motion platform reaches the theoretical trigger spacing each time, and acquiring the physical position of the motion platform; calculating the calculated position of the motion platform based on the first position synchronization signal; and performing an early warning process when the position deviation between the physical position and the calculated position is greater than a position deviation threshold.

[0008] According to the direct-write lithography machine exposure synchronization diagnosis method of the present invention, during the exposure process, the motion platform moves continuously at a preset theoretical trigger interval under drive control. Each time the movement displacement reaches the theoretical trigger interval, the motion platform driver outputs a first position synchronization signal. This position synchronization signal essentially reflects the displacement position "as perceived" by the motion platform based on control commands and drive logic. Simultaneously, by acquiring the physical position of the motion platform, such as position information fed back in real time by a position detection device like a grating ruler, the true and objective physical displacement of the motion platform relative to a reference zero point can be accurately characterized. Based on this, the calculated position of the motion platform is calculated according to the first position synchronization signal. By comparing this calculated position with the physical position reflecting the actual motion state, when the position deviation between the two is greater than a preset position deviation threshold, it indicates that the position synchronization signal can no longer accurately reflect the actual displacement state of the motion platform, suggesting that there may be problems such as abnormal position synchronization signal, trigger misalignment, or abnormal platform movement during the exposure process. Therefore, by constructing a comparison relationship between the position synchronization signal and the actual physical position, this invention realizes the diagnosis and early warning of position synchronization signal anomalies during the exposure process. Compared with the existing technology that relies solely on the position synchronization signal or single position feedback for open-loop exposure control, this invention can promptly detect and block exposure errors caused by position synchronization anomalies during the exposure process, thereby effectively reducing the risks of exposure position offset and pattern distortion, and improving the reliability of the exposure process of the direct-write lithography machine.

[0009] In some embodiments, calculating the calculated position of the motion platform based on the first position synchronization signal includes: recording the actual triggering cycle of the first position synchronization signal and the number of actual triggering cycles; and calculating the calculated position of the motion platform based on the number of actual triggering cycles and the theoretical triggering interval.

[0010] In some embodiments, the direct-write lithography machine exposure synchronization diagnosis method further includes: when the positional deviation between the physical position and the calculated position is greater than a positional deviation threshold, calibrating the calculated position of the motion platform according to the positional deviation.

[0011] In some embodiments, the direct-write lithography machine exposure synchronization diagnosis method further includes: during the exposure process, outputting a second position synchronization signal to the exposure processing module, obtaining a third position synchronization signal corresponding to the second position synchronization signal fed back by the exposure processing module, wherein the second position synchronization signal and the first position synchronization signal are both generated based on the theoretical triggering period and the preset motion speed of the motion platform; and performing an early warning process when there is a deviation between the third position synchronization signal and the second position synchronization signal.

[0012] In some embodiments, the deviation between the third position synchronization signal and the second position synchronization signal includes a deviation between the trigger period of the third position synchronization signal and the trigger period of the second position synchronization signal and / or a deviation between the number of the third position synchronization signals and the number of the second position synchronization signals.

[0013] In some embodiments, the direct-write lithography machine includes a plurality of the exposure processing modules, and the direct-write lithography machine exposure synchronization diagnosis method further includes: when any one of the first position synchronization signal and the plurality of third position signals fed back by the plurality of exposure processing modules is abnormal, locating the abnormal position according to the first position synchronization signal and the plurality of third position signals.

[0014] In some embodiments, the exposure process includes a first exposure stage and a second exposure stage; the first exposure stage is a stage for exposing non-valid graphic areas in the exposure area, and the second exposure stage is a stage for exposing valid graphic areas in the exposure area; the warning processing includes: during the first exposure stage, issuing a warning prompt and not responding to the exposure control process, and / or, during the second exposure stage, issuing a warning prompt and stopping the exposure control process.

[0015] In some embodiments, the exposure synchronization diagnosis method for direct-write lithography machines further includes: sending the synchronization signals of each position generated during the exposure process, the position information of the motion platform, and the abnormal position location information to the host computer.

[0016] To achieve the above objectives, the signal synchronization processing unit of the second aspect of the present invention is used to implement the exposure synchronization diagnosis method for direct-write lithography machines described in the above embodiment.

[0017] According to the signal synchronization processing unit of this embodiment, by employing the exposure synchronization diagnosis method for direct-write lithography machines described in the above embodiment, during the exposure process, the motion platform moves continuously at a preset theoretical trigger interval under drive control. Each time the movement displacement reaches the theoretical trigger interval, the motion platform driver outputs a first position synchronization signal. This position synchronization signal essentially reflects the displacement position "as perceived" by the motion platform based on control commands and drive logic. Simultaneously, by acquiring the physical position of the motion platform, such as the position information fed back in real time by a position detection device like a grating ruler, the true and objective physical displacement of the motion platform relative to a reference zero point can be accurately characterized. Based on this, the calculated position of the motion platform is calculated according to the first position synchronization signal. By comparing this calculated position with the physical position reflecting the actual motion state, when the position deviation between the two is greater than a preset position deviation threshold, it indicates that the position synchronization signal can no longer accurately reflect the actual displacement state of the motion platform, suggesting that there may be problems such as abnormal position synchronization signal, trigger misalignment, or abnormal platform movement during the exposure process. Therefore, by constructing a comparison relationship between the position synchronization signal and the actual physical position, this invention realizes the diagnosis and early warning of position synchronization signal anomalies during the exposure process. Compared with the existing technology that relies solely on the position synchronization signal or single position feedback for open-loop exposure control, this invention can promptly detect and block exposure errors caused by position synchronization anomalies during the exposure process, thereby effectively reducing the risks of exposure position offset and pattern distortion, and improving the reliability of the exposure process of the direct-write lithography machine.

[0018] To achieve the above objectives, a direct-write lithography machine according to a third aspect of the present invention includes: a motion platform; a motion platform driving module, the motion platform driving module being used to drive the motion platform to move according to a preset motion speed and to issue a first position synchronization signal when the movement of the motion platform reaches a theoretical triggering distance; a grating ruler encoder unit, the grating ruler encoder unit being used to obtain the physical position of the motion platform; multiple exposure processing modules, used to perform exposure processing on the exposure area; and a signal synchronization processing unit as described in the above embodiment, the signal synchronization processing unit being connected to the motion platform driving module, the grating ruler encoder unit and the multiple exposure processing modules.

[0019] According to an embodiment of the present invention, the direct-write lithography machine, by simultaneously introducing a motion platform drive module, a grating encoder unit, and a signal synchronization processing unit connected thereto into the system structure, transforms the exposure synchronization from the traditional single signal output mode to a "synchronization signal-physical position" comparative diagnostic mode. The motion platform drive module outputs a first position synchronization signal when the platform moves at a preset speed and reaches the theoretical trigger spacing. This position synchronization signal essentially reflects the displacement position "as perceived" by the motion platform based on control commands and drive logic. Simultaneously, the grating encoder unit acquires the physical position of the motion platform relative to a reference zero point in real time, reflecting the platform's actual motion state. The signal synchronization processing unit receives the first position synchronization signal and generates a corresponding calculated position based on it. It also receives the physical position fed back by the grating encoder. By comparing this calculated position with the physical position reflecting the actual motion state, if the position deviation between the two exceeds a preset position deviation threshold, it indicates that the position synchronization signal can no longer accurately reflect the actual displacement state of the motion platform, suggesting potential problems such as abnormal position synchronization signal, trigger misalignment, or abnormal platform motion during the exposure process. Therefore, by constructing a comparison relationship between the position synchronization signal and the actual physical position, this invention realizes the diagnosis and early warning of position synchronization signal anomalies during the exposure process. Compared with the existing technology that relies solely on the position synchronization signal or a single position feedback for open-loop exposure control, this invention can promptly detect and block exposure errors caused by position synchronization anomalies during the exposure process executed by multiple exposure processing modules, thereby effectively reducing the risks of exposure position offset and pattern distortion, and improving the reliability of the exposure process of the direct-write lithography machine.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart of a direct-write lithography machine exposure synchronization diagnostic method according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a non-valid graphic area and a valid graphic area according to an embodiment of the present invention; Figure 3 This is an overall flowchart of a direct-write lithography machine exposure synchronization diagnostic method according to an embodiment of the present invention; Figure 4 This is a schematic diagram of a direct-write lithography machine according to an embodiment of the present invention.

[0022] Figure label: Direct-write lithography machine 100; host computer 200; Motion platform 1; Motion platform drive module 2; Grating ruler encoder unit 3; Exposure processing module 4; Signal synchronization processing unit 5. Detailed Implementation

[0023] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention are described in detail below.

[0024] The following is for reference. Figures 1-3 A method for synchronous diagnosis of exposure in a direct-write lithography machine according to an embodiment of the present invention is described.

[0025] Figure 1 This is a flowchart of a direct-write lithography machine exposure synchronization diagnostic method according to an embodiment of the present invention, such as... Figure 1 As shown, the direct-write lithography machine exposure synchronization diagnosis method of this invention includes at least the following steps: S1, during the exposure process, acquire the first position synchronization signal when the movement platform moves to the theoretical trigger distance each time, and acquire the physical position of the movement platform.

[0026] In some embodiments, the motion platform can be a precision motion mechanism in a direct-write lithography machine used to carry a substrate or wafer and perform scanning motion according to a predetermined trajectory during the exposure process. The function of the motion platform is to sequentially send the area to be exposed into the exposure area according to the set motion trajectory and speed during the exposure process, thereby realizing the line-by-line or strip-by-strip scanning exposure of the direct-write lithography machine. Therefore, the motion accuracy and stability of the motion platform directly determine the exposure position accuracy and the exposure pattern quality.

[0027] In some embodiments, the theoretical trigger spacing can refer to the displacement interval preset during the exposure scanning process for generating position synchronization signals. Its function is to discretize the continuous displacement process of the motion platform into a series of equidistant synchronization trigger nodes, serving as a spatial reference for exposure control and synchronization diagnosis. For example, when the theoretical trigger spacing is set to 1 μm (micrometer), it means that the system should theoretically generate a position synchronization trigger signal for every 1 μm movement of the motion platform.

[0028] In some embodiments, the theoretical trigger spacing can be preset by the host computer software based on factors such as exposure resolution, image pixel size, scanning speed, and refresh capability of the exposure processing module, and sent to the motion platform drive module before exposure begins. During exposure, this theoretical trigger spacing serves as a displacement reference under ideal working conditions for the motion platform, constraining the motion platform to output a position synchronization trigger signal once every fixed distance moved.

[0029] In some embodiments, the first position synchronization signal can refer to the position signal output by the motion platform drive module when the actual displacement of the motion platform reaches the theoretical trigger distance during motion. This first position synchronization signal can characterize the displacement position "as perceived" by the motion platform on the drive and control side. Therefore, by acquiring the first position synchronization signal each time the motion platform's displacement reaches the theoretical trigger distance, motion displacement information calculated based on the platform drive and control logic can be obtained, thereby providing a basis for subsequent calculation of the motion platform's position.

[0030] In some embodiments, the first position synchronization signal can be generated by the motion platform drive module, such as by a motion controller, servo driver, or platform driver that internally accumulates the platform command displacement or encoder feedback displacement and outputs it when the theoretical trigger interval is reached. The first position synchronization signal is a periodic square wave or pulse signal. Its actual trigger period may be affected by factors such as platform speed fluctuations and control errors, but each trigger corresponds to a synchronization determination of "theoretical displacement in place".

[0031] In some embodiments, the physical position of the motion platform can refer to the actual mechanical displacement of the motion platform relative to the reference zero point, which can truly reflect the actual motion state of the platform in space. The purpose of obtaining the physical position of the motion platform is to provide an objective physical reference for exposure synchronization diagnosis, so as to subsequently determine whether there is a large deviation between the drive-side position synchronization signal and the actual motion of the platform.

[0032] In some embodiments, the physical position of the motion platform can be obtained by the grating ruler encoder unit. For example, by acquiring the A-phase and B-phase pulse signals and the Z-phase index signal output by the grating ruler, the real-time displacement of the platform is counted and calculated with high precision to obtain the real-time physical position of the platform relative to the reference zero point. Among them, the A-phase and B-phase pulses are used to characterize the continuous displacement change of the platform, and the Z-phase signal is used to provide the reference zero point or periodic calibration, so that the obtained physical position has high accuracy and reliability, thereby providing a reliable physical position basis for subsequent exposure synchronization diagnosis.

[0033] S2, calculate the position of the motion platform based on the first position synchronization signal.

[0034] In some embodiments, calculating the calculated position of the motion platform based on the first position synchronization signal includes: recording the actual triggering cycle and the number of actual triggering cycles of the first position synchronization signal, and calculating the calculated position of the motion platform based on the number of actual triggering cycles and the theoretical triggering interval.

[0035] In some embodiments, such as Figure 2As shown, the actual triggering period T1 of the first position synchronization signal can refer to the actual time interval between two consecutive triggering of the first position synchronization signal. This actual triggering period reflects the real time length experienced by the motion platform during actual operation for each "theoretical displacement arrival determination". Since the motion platform may be affected by factors such as instantaneous speed fluctuations and jitter during operation, causing periodic fluctuations in the triggering period, the actual triggering period may deviate from the theoretical triggering period of the motion platform under ideal conditions with equal-distance triggering.

[0036] In some embodiments, the actual number of trigger cycles may refer to the cumulative number of times the first position synchronization signal is triggered during the exposure process, which is used to characterize how many equidistant displacements corresponding to the theoretical trigger interval are determined to have been completed by the motion platform on the drive and control side within the current exposure scan interval.

[0037] In some embodiments, the calculated position of the motion platform is obtained based on the actual number of trigger cycles and the theoretical trigger interval. This can be understood as follows: the first position synchronization signal is regarded as a "displacement counting benchmark" based on the drive and control side. Each time the first position synchronization signal is triggered, the system considers that the motion platform has completed a displacement equal to the theoretical trigger interval. Therefore, the calculated position of the motion platform can be obtained by multiplying the cumulative number of triggers of the first position synchronization signal by the theoretical trigger interval. For example, if the first position synchronization signal is recorded to be triggered N times during the exposure process, and the theoretical trigger interval corresponding to each trigger is D, then the calculated position of the motion platform can be represented as N×D. This calculated position does not directly reflect the actual mechanical displacement of the platform, but rather reflects the displacement position "identified" by the platform at the control system and synchronization logic level. It is used to compare with the physical position obtained by high-precision measurement units such as grating rulers to determine whether there is a large abnormal deviation in the position synchronization signal.

[0038] In some embodiments, before recording the actual triggering period and the number of actual triggering periods of the first position synchronization signal, the signal synchronization processing unit can perform algorithm filtering and real-time monitoring and analysis on the first position synchronization signal generated by the motion platform drive module. The purpose of algorithm filtering is to denoise the signal, removing high-frequency noise caused by interference or jitter; the purpose of real-time monitoring and analysis is to determine the integrity and periodic stability of the signal.

[0039] S3: When the positional deviation between the physical location and the calculated location exceeds the positional deviation threshold, an early warning is issued.

[0040] In some embodiments, when the positional deviation between the physical position and the calculated position exceeds a positional deviation threshold, it indicates an unacceptable difference between the calculated position obtained from the first position synchronization signal generated by the motion platform drive module and the actual physical position of the motion platform obtained by a position detection unit such as a grating ruler. This difference reflects potential issues such as uneven motion speed, abnormal drive control, abnormal triggering of the position synchronization signal, or abnormal signal transmission during the exposure process, which could lead to risks of exposure position offset, abnormal exposure energy distribution, or image distortion. In some embodiments, the position deviation threshold can be set according to factors such as the exposure accuracy requirements of the direct-write lithography machine, the pattern resolution, the theoretical trigger spacing, and the process tolerance.

[0041] In some embodiments, early warning processing can refer to an abnormal prompt or protective measure automatically triggered by the system when a position deviation is detected to be greater than a position deviation threshold. This serves to alert the operator or the upper-level control system that there is a risk in the current exposure synchronization status. Through early warning processing measures, intervention can be taken promptly when an abnormal position synchronization signal occurs, thereby preventing the continuation of exposure operations under abnormal conditions, reducing the risk of batch exposure defects, and improving the reliability of the exposure process. According to the direct-write lithography machine exposure synchronization diagnosis method of the present invention, during the exposure process, the motion platform moves continuously at a preset theoretical trigger interval under drive control. Each time the movement displacement reaches the theoretical trigger interval, the motion platform driver outputs a first position synchronization signal. This position synchronization signal essentially reflects the displacement position "as perceived" by the motion platform based on control commands and drive logic. Simultaneously, by acquiring the physical position of the motion platform, such as position information fed back in real time by a position detection device like a grating ruler, the true and objective physical displacement of the motion platform relative to a reference zero point can be accurately characterized. Based on this, the calculated position of the motion platform is calculated according to the first position synchronization signal. By comparing this calculated position with the physical position reflecting the actual motion state, when the position deviation between the two is greater than a preset position deviation threshold, it indicates that the position synchronization signal can no longer accurately reflect the actual displacement state of the motion platform, suggesting that there may be problems such as abnormal position synchronization signal, trigger misalignment, or abnormal platform movement during the exposure process. Therefore, by constructing a comparison relationship between the position synchronization signal and the actual physical position, this invention realizes the diagnosis and early warning of position synchronization signal anomalies during the exposure process. Compared with the existing technology that relies solely on the position synchronization signal or single position feedback for open-loop exposure control, this invention can promptly detect and block exposure errors caused by position synchronization anomalies during the exposure process, thereby effectively reducing the risks of exposure position offset and pattern distortion, and improving the reliability of the exposure process of the direct-write lithography machine.

[0042] In some embodiments, the exposure synchronization diagnosis method for a direct-write lithography machine further includes: when the position deviation between the physical position and the calculated position is greater than a position deviation threshold, calibrating the calculated position of the motion platform according to the position deviation.

[0043] Specifically, when the signal synchronization processing unit acquires the first position synchronization signal each time the motion platform's displacement reaches the theoretical trigger spacing, the signal synchronization processing unit synchronously collects the physical position data output by the grating ruler encoder and records the corresponding actual physical coordinates as Y1. Based on this, the signal synchronization processing unit can actively generate a companion synchronization position signal for benchmarking based on the actual physical position. Therefore, the companion synchronization position signal is not additionally output by the motion platform drive module, but is derived by the signal synchronization processing unit based on the actual displacement measured by the grating ruler, and is used to identify the equidistant displacement reference trigger point corresponding to the theoretical trigger spacing in the physical coordinate system. By comparing the calculated position corresponding to the first position synchronization signal with the recorded physical coordinates Y1, the position deviation between the physical position and the calculated position can be obtained, and the calculated position obtained based on the first position synchronization signal can be corrected or updated accordingly, thereby achieving calibration of the motion platform's calculated position.

[0044] In some embodiments, the accompanying synchronous position signal is used to assist in establishing the correspondence between the calculated position and the physical position, providing a reliable reference for subsequent position deviation judgment and calculated position calibration.

[0045] In some embodiments, calibrating the calculated position of the motion platform can be equivalent to correcting, resetting, or updating the actual number of trigger cycles used to calculate the calculated position, so that the position result obtained based on the first position synchronization signal is re-aligned with the actual physical position measured by the grating ruler, thereby eliminating the position accumulation deviation caused by synchronization signal abnormality or trigger error.

[0046] In some embodiments, the purpose of calibrating the calculated position is to suppress or eliminate the cumulative deviation of the calculated position caused by factors such as abnormal position synchronization signals, trigger jitter, signal transmission delays, or instantaneous speed fluctuations of the motion platform, preventing this deviation from continuously amplifying during exposure and further affecting the exposure synchronization accuracy. By calibrating the calculated position using the high-precision physical position provided by the grating ruler when the position deviation between the physical position and the calculated position exceeds the position deviation threshold, the position perception obtained based on the position synchronization signal can be re-aligned with the actual physical position of the motion platform. This ensures that subsequent exposure triggering is based on a reliable position reference, improving the reliability of the exposure process and the imaging quality of the exposure pattern.

[0047] In some embodiments, the exposure synchronization diagnosis method for a direct-write lithography machine further includes: during the exposure process, outputting a second position synchronization signal to the exposure processing module, and acquiring a third position synchronization signal corresponding to the second position synchronization signal fed back by the exposure processing module. Both the second and first position synchronization signals are generated based on a theoretical trigger period and a preset motion platform speed. When there is a deviation between the third and second position synchronization signals, an early warning process is performed.

[0048] In some embodiments, the second position synchronization signal may refer to a synchronization signal output by the synchronization signal processing unit to the exposure processing module during the exposure process, used to indicate the theoretical exposure trigger position. The second position synchronization signal may be generated based on the theoretical trigger period and the preset motion speed of the motion platform, used to characterize the theoretical position beat at which the exposure processing module should perform exposure trigger or exposure pattern refresh operation under ideal motion conditions.

[0049] In some embodiments, the second position synchronization signal is different from the synchronization signal directly used for motion control. Its main function is to provide a unified and predictable exposure trigger position reference for the exposure processing module, thereby ensuring the consistency between the exposure pattern refresh timing and the theoretical position of the motion platform.

[0050] In some embodiments, the exposure processing module may include a DMD (Digital Micromirror Device) control unit, a laser driving unit, and related exposure control circuitry. Its main function is to control the DMD array to refresh and display the exposure pattern after receiving a second position synchronization signal, and to synchronously trigger the laser to output exposure energy. By establishing a synchronization signal interaction relationship between the exposure processing module and the signal synchronization processing unit, the exposure operation can be strictly controlled by the platform position synchronization logic, improving exposure consistency and controllability.

[0051] In some embodiments, the third position synchronization signal may refer to the synchronization confirmation signal fed back to the signal synchronization processing unit by the exposure processing module after receiving the second position synchronization signal. This signal is used to characterize the actual reception of the second position synchronization signal by the exposure processing module, so as to confirm whether the second position synchronization signal has been correctly received.

[0052] Therefore, the purpose of introducing a third position synchronization signal is to construct a closed-loop monitoring mechanism for the exposure control link. By enabling the exposure processing module to immediately feed back the received second position synchronization signal as a third position synchronization signal, the signal synchronization processing unit can determine in real time whether there are any abnormalities such as delays, loss, or jitters in the transmission and processing of the synchronization signal, thereby preventing the exposure action from deviating from the expected timing without being detected.

[0053] In some embodiments, both the second position synchronization signal and the first position synchronization signal are generated based on the theoretical trigger cycle and the preset motion speed of the motion platform. The first position synchronization signal characterizes the position "as perceived" by the motion platform on the drive and control side, while the second position synchronization signal characterizes the theoretical position timing at which the exposure processing module should perform exposure triggering or exposure pattern refresh operations under ideal motion conditions. Both signals share the same generation basis but apply to different objects: the motion platform side and the exposure execution side, respectively, thus achieving consistent synchronization across modules.

[0054] Among them, such as Figure 2 As shown, the theoretical trigger period refers to the theoretical time interval between two adjacent position synchronization triggers when the motion platform moves at a preset uniform speed under ideal working conditions. This theoretical trigger period can be determined by both the theoretical trigger spacing and the preset motion platform speed. For example, when the theoretical trigger spacing is D and the preset motion platform speed is V, the theoretical trigger period can be expressed as T0 = D / V. The theoretical trigger period describes the reference period that the position synchronization signal should generate according to a fixed time rhythm under ideal conditions with no speed fluctuations and no control errors, thus providing a time reference for the generation and verification of the position synchronization signal.

[0055] In some embodiments, such as Figure 2 As shown, when the actual trigger period of the first position synchronization signal is inconsistent with the theoretical trigger period (there is an error time ΔT), it indicates that the motion platform does not move at a uniform speed according to the preset motion speed during actual operation, or that there is timing jitter or delay in the generation or transmission of the first position synchronization signal. Since the theoretical trigger period reflects the time reference corresponding to the motion platform completing an equidistant displacement under ideal conditions, the deviation of the actual trigger period from the theoretical trigger period can directly reflect the speed fluctuation, control error, or synchronization signal abnormality of the motion platform, thereby affecting the accuracy of the calculated position of the motion platform based on the first position synchronization signal, and thus affecting the consistency between the exposure trigger position and the actual physical position of the platform, ultimately leading to exposure position offset and exposure pattern distortion.

[0056] In some embodiments, a deviation between the third position synchronization signal and the second position synchronization signal indicates an anomaly in the exposure processing module's reception or processing of the synchronization signal, such as signal transmission delay, jitter or abnormal interference, processing blockage, untimely module response, or interface malfunction. By implementing an early warning system for this deviation, problems with the exposure-side synchronization link can be detected promptly during the exposure process, preventing mismatch between the exposure action and the platform's movement position, thereby reducing risks such as exposure offset, image distortion, or abnormal energy distribution.

[0057] In some embodiments, the deviation between the third position synchronization signal and the second position synchronization signal includes a deviation between the trigger period of the third position synchronization signal and the trigger period of the second position synchronization signal and / or a deviation between the number of third position synchronization signals and the number of second position synchronization signals.

[0058] In some embodiments, before performing deviation analysis on the third position synchronization signal and the second position synchronization signal, the signal synchronization processing unit can record and statistically analyze the third position synchronization signal fed back by the exposure processing module, including recording the actual trigger period T2 of the third position synchronization signal and the corresponding number information N2, and comparing the recorded T2 and N2 with the trigger period and number information of the second position synchronization signal, thereby determining whether there is a trigger period deviation and / or a number deviation, and triggering an early warning process accordingly.

[0059] In some embodiments, the trigger period of the third position synchronization signal deviates from that of the second position synchronization signal, which may be caused by an abnormality in the exposure processing module itself or by an abnormality in the transmission of the second and third position synchronization signals. For example, ideally, the second position synchronization signal is output to the exposure processing module with a theoretical trigger period T0, and the exposure processing module should return the third position synchronization signal with the same trigger period. However, in actual operation, due to factors such as processing delay, clock drift, and interface jitter within the exposure processing module, or jitter or loss of the synchronization signal during transmission, the actual trigger period of the third position synchronization signal may become T2, and T2 deviates from T0, thus reflecting the inconsistency in the response rhythm of the exposure processing module to the position synchronization signal.

[0060] In some embodiments, the number of third position synchronization signals deviates from the number of second position synchronization signals. This can be understood as the exposure processing module experiencing loss, duplication, or abnormal shielding during the reception or processing of the second position synchronization signals. For example, during exposure, the signal synchronization processing unit continuously outputs multiple second position synchronization signals to the exposure processing module. However, due to internal busyness, abnormal interruption, or abnormal signal transmission within the exposure processing module, the number of third position synchronization signals returned by the exposure processing module may be more or less than the corresponding number of second position synchronization signals, resulting in an inconsistency in the number of position synchronization signals. This type of deviation reflects problems such as pulse loss, repeated triggering, or abnormal feedback during the reception or feedback of position synchronization signals by the exposure processing module.

[0061] In some embodiments, the impact of the trigger cycle deviation and the number information deviation of the third position synchronization signal on the exposure process is not entirely the same. The trigger cycle deviation mainly reflects the instability of the exposure trigger clock in the time dimension, easily leading to spatial continuity errors or local stretching / compression of the exposure position. The number information deviation, on the other hand, reflects the inconsistency in the number of exposure trigger events, easily leading to problems such as missing exposure strips, repeated exposures, or scan segment misalignment. Both types of deviations can disrupt the consistency between position and timing during the exposure process, and therefore both require early warning processing.

[0062] In some embodiments, the direct-write lithography machine includes multiple exposure processing modules, and the direct-write lithography machine exposure synchronization diagnosis method further includes: when any one of the first position synchronization signal and multiple third position signals fed back by the multiple exposure processing modules is abnormal, locating the abnormal position according to the first position synchronization signal and the multiple third position signals.

[0063] In some embodiments, the abnormal location may include, but is not limited to, at least one of the following: abnormal movement of the motion platform, abnormal operation of the exposure processing module itself, abnormal signal transmission between the motion platform drive module and the signal synchronization processing unit, and abnormal signal transmission between the signal synchronization processing unit and the exposure processing module.

[0064] In some embodiments, the signal synchronization processing unit can uniformly record and time-align the first position synchronization signal and the third position synchronization signals fed back by multiple exposure processing modules, and determine and locate abnormal positions based on the trigger cycle information and trigger count information of each position synchronization signal. For example, the calculated position of the motion platform is obtained by calculating the actual trigger cycle count and theoretical trigger spacing of the first position synchronization signal. When the position deviation between the calculated position and the physical position of the motion platform is greater than a preset position deviation threshold, it indicates that there is a motion abnormality in the motion platform during the exposure scanning process, or there is a transmission abnormality of the position synchronization signal between the motion platform drive module and the signal synchronization processing unit. As another example, during the exposure process, when the first position synchronization signal works normally, but only the third position synchronization signal fed back by a certain exposure processing module shows an abnormal trigger cycle or a missing trigger count, it can be determined that the abnormal position is concentrated in the exposure processing module itself, or concentrated in the signal transmission link between the signal synchronization processing unit and the exposure processing module.

[0065] In some embodiments, by locating the abnormal position based on the first position synchronization signal and multiple third position synchronization signals, the specific location or module where the exposure abnormality occurred can be quickly determined during or after the exposure process. This provides clear guidance for subsequent anomaly analysis, troubleshooting, and maintenance, thereby improving the exposure stability and maintenance efficiency of the direct-write lithography machine.

[0066] In some embodiments, the exposure process includes a first exposure stage and a second exposure stage. The first exposure stage is for exposing non-effective graphic areas within the exposure area, and the second exposure stage is for exposing effective graphic areas within the exposure area.

[0067] In some embodiments, a non-effective patterned area may refer to a region located at the beginning or edge of each exposed image segment, which does not contain effective circuit patterns or functional structure patterns that need to be ultimately transferred to the substrate. For example, such as Figure 2 As shown, the non-effective graphic area can be used for optical stabilization of the exposure start segment, acceleration and deceleration transition of the motion platform, establishment of position synchronization signal, and system status verification, and its length can be preset to H.

[0068] In some embodiments, during the first exposure stage, the motion platform drive module continues to move along the predetermined scanning path and generates a corresponding first position synchronization signal. However, the exposure control module does not refresh or display the actual exposed image according to the second position synchronization signal during this stage, i.e., it does not output the exposure of the valid graphic. This non-valid graphic area can essentially be regarded as a "synchronization detection and stabilization confirmation area" before exposure.

[0069] In some embodiments, such as Figure 2 As shown, the effective graphic area can refer to the area in the exposure area that actually carries the target graphic information. The exposure result in this area will directly affect the forming quality of the final device or circuit structure, and its length can be preset to I.

[0070] In some embodiments, during the second exposure stage, the exposure control module performs real-time refresh control on the digital micromirror device (DMD) or other exposure components based on the second position synchronization signal generated by the signal synchronization processing unit, thereby completing the exposure processing of the effective graphic area.

[0071] In some embodiments, the warning processing includes: during the first exposure phase, issuing a warning and not responding to the exposure control process, and / or, during the second exposure phase, issuing a warning and stopping the exposure control process.

[0072] Specifically, during the first exposure stage, if the synchronization signal processing unit detects an anomaly in the synchronization signal at the first position within a non-effective graphic area, it issues a warning but does not respond to the exposure control process, i.e., it does not trigger the exposure action of the effective graphic. This method allows for the early detection of potential synchronization signal anomalies without affecting the final exposed graphic quality, preventing anomalies from being detected only after entering the effective graphic area. During the second exposure stage, if the synchronization signal processing unit detects an anomaly in the synchronization signal at the third position within the effective graphic area, it issues a warning and stops the exposure control process. By directly stopping exposure within the effective graphic area, it prevents continued exposure of the effective graphic under abnormal synchronization signal conditions, avoiding irreversible exposure defects such as graphic misalignment, linewidth distortion, or abnormal energy distribution, thereby reducing the probability of defective products.

[0073] In some embodiments, the exposure synchronization diagnosis method for direct-write lithography machines further includes: sending synchronization signals at various positions generated during the exposure process, position information of the motion platform, and abnormal position location information to the host computer.

[0074] In some embodiments, the position information of the motion platform may include the platform's real-time physical position coordinates, the calculated position based on the first position synchronization signal, and the equidistant trigger point position marked by the synchronization position signal. This information can reflect the motion state and displacement of the motion platform during the exposure process, providing basic data for subsequent diagnosis and analysis.

[0075] In some embodiments, the abnormal location information may include the specific coordinates of the located abnormal location, the module or link where the abnormality occurred (e.g., a specific exposure processing module or signal link), the type of abnormality (e.g., trigger cycle abnormality, number information deviation), and error code information related to the abnormality, for the purpose of quickly identifying and handling problems in subsequent analysis and maintenance.

[0076] Figure 3 This is an overall flowchart of a direct-write lithography machine exposure synchronization diagnostic method according to an embodiment of the present invention, as follows: Figure 3 As shown, the overall process of the exposure synchronization diagnosis method for direct-write lithography machines includes at least the following steps: S10, the host computer software sets the motion speed, triggering method and theoretical triggering interval of the motion platform drive module.

[0077] S11, drive the motion platform to move according to the preset motion speed and issue the first position synchronization signal when the movement of the motion platform reaches the theoretical trigger distance.

[0078] S12, during the exposure process, the signal synchronization processing unit performs algorithm filtering and real-time monitoring and analysis on the first position synchronization signal generated by the motion platform drive module, and simultaneously obtains the physical position of the motion platform.

[0079] S13, calculate the calculated position of the motion platform based on the first position synchronization signal, and perform early warning processing when the position deviation between the physical position and the calculated position is greater than the position deviation threshold.

[0080] S14, during the exposure process, the signal synchronization processing unit outputs a second position synchronization signal to the exposure processing module. The exposure control module receives the second position synchronization signal and controls the DMD digital micromirror to refresh and display the exposure pattern. At the same time, the exposure processing module immediately feeds back the third position synchronization signal corresponding to the received second position synchronization signal to the signal synchronization processing unit for closed-loop monitoring.

[0081] S15 sends the synchronization signals of each position generated during the exposure process, the position information of the motion platform, and the abnormal position location information to the host computer.

[0082] In summary, by constructing a monitoring loop channel to monitor the position synchronization signal and the position information of the motion platform in real time during the exposure process, abnormal positions can be quickly located and the efficiency of anomaly investigation can be greatly improved. This effectively reduces the risks of exposure position deviation and pattern distortion, and improves the reliability of the exposure process of the direct-write lithography machine.

[0083] This invention also proposes a signal synchronization processing unit.

[0084] In some embodiments, the signal synchronization processing unit may include a microcontroller unit (MCU), a digital signal processor (DSP), a field-programmable gate array (FPGA), or an application-specific integrated circuit (ASIC), and is equipped with corresponding software or logic circuits to implement the direct-write lithography machine exposure synchronization diagnosis method described in the above embodiments.

[0085] According to the signal synchronization processing unit of this embodiment, by employing the exposure synchronization diagnosis method for direct-write lithography machines described in the above embodiment, during the exposure process, the motion platform moves continuously at a preset theoretical trigger interval under drive control. Each time the movement displacement reaches the theoretical trigger interval, the motion platform driver outputs a first position synchronization signal. This position synchronization signal essentially reflects the displacement position "as perceived" by the motion platform based on control commands and drive logic. Simultaneously, by acquiring the physical position of the motion platform, such as the position information fed back in real time by a position detection device like a grating ruler, the true and objective physical displacement of the motion platform relative to a reference zero point can be accurately characterized. Based on this, the calculated position of the motion platform is calculated according to the first position synchronization signal. By comparing this calculated position with the physical position reflecting the actual motion state, when the position deviation between the two is greater than a preset position deviation threshold, it indicates that the position synchronization signal can no longer accurately reflect the actual displacement state of the motion platform, suggesting that there may be problems such as abnormal position synchronization signal, trigger misalignment, or abnormal platform movement during the exposure process. Therefore, by constructing a comparison relationship between the position synchronization signal and the actual physical position, this invention realizes the diagnosis and early warning of position synchronization signal anomalies during the exposure process. Compared with the existing technology that relies solely on the position synchronization signal or single position feedback for open-loop exposure control, this invention can promptly detect and block exposure errors caused by position synchronization anomalies during the exposure process, thereby effectively reducing the risks of exposure position offset and pattern distortion, and improving the reliability of the exposure process of the direct-write lithography machine.

[0086] The following is for reference. Figure 4 A direct-write lithography machine according to an embodiment of the present invention is described.

[0087] Figure 4 This is a schematic diagram of a direct-write lithography machine according to an embodiment of the present invention, as shown below. Figure 4 As shown, the direct-write lithography machine includes: a motion platform, a motion platform drive module, a grating encoder unit, multiple exposure processing modules, and the signal synchronization processing unit described in the above embodiment.

[0088] In some embodiments, the motion platform may be a precision motion mechanism in a direct-write lithography machine used to carry a substrate or wafer and to perform scanning motion along a predetermined trajectory during the exposure process.

[0089] In some embodiments, the motion platform drive module may refer to an actuator or drive unit for driving the motion platform to move along a predetermined trajectory, such as a linear motor, stepper motor, servo motor or other driver that can precisely control displacement. Its function is to drive the motion platform to move according to a preset motion speed and to issue a first position synchronization signal when the movement of the motion platform reaches the theoretical triggering distance.

[0090] In some embodiments, the grating encoder unit can refer to a high-precision position measuring device mounted on a motion platform, used to acquire the physical position information of the motion platform in real time. This unit can output precise displacement data, such as A / B phase pulse signals and indexed Z-phase signals, and calculate the real-time physical position of the platform using these signals for comparison and calibration of platform motion. The grating encoder unit can be a linear grating ruler, magnetic grating ruler, or other high-precision position measuring sensor.

[0091] In some embodiments, each exposure processing module may include a DMD digital micromirror control unit, a laser driving unit, and an associated exposure control circuit for exposing the exposure area.

[0092] In some embodiments, the signal synchronization processing unit is connected to the motion platform drive module, the grating ruler encoder unit, and multiple exposure processing modules. Its functions include: receiving a first position synchronization signal output by the motion platform drive module; receiving physical position data provided by the grating ruler encoder unit; outputting a second position synchronization signal to each exposure processing module; receiving a third position synchronization signal fed back by the exposure processing modules; comparing and calculating the triggering period and number of the position with the physical position, and the second and third position synchronization signals; recording each position synchronization signal and abnormal information; and realizing closed-loop monitoring and abnormal early warning of the exposure process. Through these functions, the signal synchronization processing unit can ensure that the exposure triggering and the motion platform position remain highly consistent, improving the accuracy and reliability of the exposure pattern.

[0093] In some embodiments, the signal synchronization processing unit can also be connected to a host computer to upload the synchronization signals generated during the exposure process, the position information of the motion platform, and the location information of abnormal positions to the host computer. Through the host computer, remote monitoring, data recording, anomaly analysis, system debugging, and maintenance management can be achieved, thereby providing support for the optimization of lithography machine operation, fault diagnosis, and production capacity management.

[0094] According to an embodiment of the present invention, the direct-write lithography machine, by simultaneously introducing a motion platform drive module, a grating encoder unit, and a signal synchronization processing unit connected thereto into the system structure, transforms the exposure synchronization from the traditional single signal output mode to a "synchronization signal-physical position" comparative diagnostic mode. The motion platform drive module outputs a first position synchronization signal when the platform moves at a preset speed and reaches the theoretical trigger spacing. This position synchronization signal essentially reflects the displacement position "as perceived" by the motion platform based on control commands and drive logic. Simultaneously, the grating encoder unit acquires the physical position of the motion platform relative to a reference zero point in real time, reflecting the platform's actual motion state. The signal synchronization processing unit receives the first position synchronization signal and generates a corresponding calculated position based on it. It also receives the physical position fed back by the grating encoder. By comparing this calculated position with the physical position reflecting the actual motion state, if the position deviation between the two exceeds a preset position deviation threshold, it indicates that the position synchronization signal can no longer accurately reflect the actual displacement state of the motion platform, suggesting potential problems such as abnormal position synchronization signal, trigger misalignment, or abnormal platform motion during the exposure process. Therefore, by constructing a comparison relationship between the position synchronization signal and the actual physical position, this invention realizes the diagnosis and early warning of position synchronization signal anomalies during the exposure process. Compared with the existing technology that relies solely on the position synchronization signal or a single position feedback for open-loop exposure control, this invention can promptly detect and block exposure errors caused by position synchronization anomalies during the exposure process executed by multiple exposure processing modules, thereby effectively reducing the risks of exposure position offset and pattern distortion, and improving the reliability of the exposure process of the direct-write lithography machine.

[0095] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0096] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for exposure synchronization diagnosis of a direct write lithography machine, characterized in that, The method comprises the following steps: During the exposure process, a first position synchronization signal is obtained when the displacement of the moving platform reaches a theoretical trigger interval, and a physical position of the moving platform is obtained; A calculated position of the moving platform is calculated according to the first position synchronization signal; When the position deviation between the physical position and the calculated position is greater than a position deviation threshold, a warning process is performed.

2. The exposure synchronization diagnostic method for a direct write lithography machine according to claim 1, wherein The method for calculating the calculated position of the moving platform according to the first position synchronization signal comprises the following steps: The actual trigger cycle of the first position synchronization signal and the number information of the actual trigger cycle are recorded; The calculated position of the moving platform is calculated according to the number information of the actual trigger cycle and the theoretical trigger interval.

3. The exposure synchronization diagnostic method for a direct write lithography machine according to claim 1, wherein The exposure synchronization diagnosis method of the direct writing lithography machine further comprises the following steps:

4. The exposure synchronization diagnostic method for a direct write lithography machine according to claim 1, wherein, When the position deviation between the physical position and the calculated position is greater than a position deviation threshold, the calculated position of the moving platform is calibrated according to the position deviation. The exposure synchronization diagnosis method of the direct writing lithography machine further comprises the following steps: During the exposure process, a second position synchronization signal is output to an exposure processing module, and a third position synchronization signal corresponding to the second position synchronization signal is obtained through feedback of the exposure processing module, wherein the second position synchronization signal and the first position synchronization signal are both generated based on a theoretical trigger cycle and a preset moving speed of the moving platform; 5. The exposure synchronization diagnostic method for a direct write lithography machine according to claim 4, wherein, When the third position synchronization signal deviates from the second position synchronization signal, a warning process is performed.

6. The exposure synchronization diagnostic method for a direct write lithography machine according to claim 5, wherein, The deviation between the third position synchronization signal and the second position synchronization signal includes a deviation between the trigger cycle of the third position synchronization signal and the trigger cycle of the second position synchronization signal and / or a deviation between the number information of the third position synchronization signal and the number information of the second position synchronization signal. The direct writing lithography machine comprises a plurality of exposure processing modules, and the exposure synchronization diagnosis method of the direct writing lithography machine further comprises the following steps:

7. The exposure synchronization diagnostic method for a direct write lithography machine according to any one of claims 1 to 6, wherein When any one of the first position synchronization signal and a plurality of third position signals fed back by a plurality of exposure processing modules is abnormal, an abnormal position is located according to the first position synchronization signal and the plurality of third position signals. The exposure process comprises a first exposure stage and a second exposure stage; The first exposure stage is a stage for exposing a non-effective pattern area in an exposure area, and the second exposure stage is a stage for exposing an effective pattern area in the exposure area; 8. The exposure synchronization diagnostic method for a direct write lithography machine according to any one of claims 1 to 6, wherein The warning process comprises the following steps: in the first exposure stage, a warning prompt is given and the exposure control process is not responded, and / or in the second exposure stage, a warning prompt is given and the exposure control process is stopped. The exposure synchronization diagnosis method of the direct writing lithography machine further comprises the following steps:

9. A signal synchronization processing unit, characterized by comprising: Each position synchronization signal generated during the exposure process, position information of the moving platform, and abnormal position locating information are sent to an upper computer.

10. A direct write lithography machine, characterized by, The exposure synchronization diagnosis method of the direct writing lithography machine is used to realize any one of claims 1-8. The method comprises the following steps: A moving platform; a motion platform driving module, configured to drive the motion platform to move according to a preset motion speed and send a first position synchronization signal when the motion platform reaches a theoretical trigger distance; a grating ruler encoder unit, configured to obtain a physical position of the motion platform; a plurality of exposure processing modules, configured to perform exposure processing on an exposure area; the signal synchronization processing unit of claim 9, connected with the motion platform driving module, the grating ruler encoder unit and the plurality of exposure processing modules.

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