A method of monitoring a processing plant

Abstract

A kind of monitoring method of processing equipment, the processing equipment includes motion platform, image acquisition system and processing system, the motion platform carries workpiece and moves to image acquisition system and processing system, at least one face edge of the motion platform is provided with multiple auxiliary positioning points, the auxiliary positioning point can be grabbed by image acquisition system when workpiece is placed on motion platform, at least one theoretical distance of auxiliary mark point is acquired before workpiece is processed, and reference spacing error threshold is set;During the operation of the motion platform with workpiece, the image acquisition system obtains at least one actual measurement distance of the auxiliary mark point corresponding to the theoretical distance, compares the actual measurement distance with the corresponding theoretical distance, obtains the current spacing error, and compares with spacing error threshold to judge whether the workpiece can be processed by processing system.In front of workpiece is exposed, that is, the exposure accuracy of workpiece is monitored, to avoid workpiece scrap.

Description

Technical Field

[0001] This invention relates to a method for monitoring processing equipment, and in particular to a method for monitoring the accuracy of processing equipment. Background Technology

[0002] During the use of production and processing equipment, it is usually necessary to monitor the operating status of the equipment to avoid scrapping the processed workpieces due to equipment errors.

[0003] In the field of direct-write exposure technology, especially for inner layer boards requiring double-sided processing, it is essential to ensure that the patterns on the front and back sides of the inner layer board correspond. To guarantee exposure accuracy, direct-write exposure equipment is equipped with a marking device on the suction cup supporting the inner layer board. When the inner layer board is exposed from the front, the marking device marks alignment points on the back side of the inner layer board. When the inner layer board is exposed from the front, the alignment points on the back side are obtained, ensuring that the patterns on the front and back sides of the inner layer board correspond. To monitor the alignment accuracy of the inner layer board, when aligning the back side of the inner layer board, it is monitored whether the obtained alignment points exceed a set PE value. If the set PE value is exceeded, exposure is rejected, thus ensuring the exposure accuracy of the inner layer board.

[0004] While the above method can monitor the exposure accuracy of the inner layer board, if the PE limit is exceeded during back exposure, the inner layer board that has completed front exposure cannot continue processing, resulting in a waste of workpieces and a waste of processing time on the front side of the inner layer board, thus affecting the efficiency of double-sided processing. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for monitoring processing equipment to prevent workpiece scrapping.

[0006] A monitoring method for a processing equipment, the processing equipment including a motion platform, an image acquisition system, and a processing system, wherein the motion platform carries a workpiece and moves it to the image acquisition system and the processing system, and at least one surface edge of the motion platform is provided with multiple auxiliary positioning points, which can be captured by the image acquisition system when the workpiece is placed on the motion platform. Before the workpiece is processed, at least one theoretical distance of the auxiliary positioning points is acquired, and a reference spacing error threshold is set; during the operation of the motion platform moving the workpiece, the image acquisition system acquires at least one actual measured distance of the auxiliary positioning points corresponding to the theoretical distance, compares the actual measured distance with the corresponding theoretical distance to obtain the current spacing error, and compares it with the spacing error threshold to determine whether the workpiece can be processed by the processing system.

[0007] A monitoring method for a processing equipment includes a motion platform, an image acquisition system, and a processing system. The motion platform carries a workpiece and moves it to the image acquisition system and the processing system. At least one edge of the motion platform has multiple auxiliary positioning points. These auxiliary positioning points can be captured by the image acquisition system when the workpiece is placed on the motion platform. Before processing the workpiece, at least one theoretical distance between the auxiliary positioning points is acquired, and a baseline spacing error threshold and a spacing error difference threshold are set. During the movement of the workpiece by the motion platform, the image acquisition system acquires at least one actual measured distance corresponding to the theoretical distance of the auxiliary positioning points. The actual measured distance is compared with the corresponding theoretical distance to obtain the current spacing error. The current spacing error is compared with an adjacent previously acquired spacing error to obtain a spacing error difference. Based on whether the spacing error difference is within the spacing error difference threshold range, it is determined whether the processing equipment can continue processing.

[0008] The theoretical distance is the calibration distance of the auxiliary marker point.

[0009] The measured distance and calibration distance refer to the straight-line distance between two auxiliary marker points.

[0010] When the motion platform has multiple auxiliary positioning points set on at least two platform edges, when obtaining the theoretical distance and the measured distance, at least three auxiliary marker points that are not on the same straight line are selected, and the distance between any two auxiliary marker points is obtained to obtain at least three actual distances and theoretical distances.

[0011] For newly started equipment, the first spacing error is controlled based on the reference spacing error threshold. It is determined whether the spacing error exceeds the range of the reference spacing error threshold. If it does not exceed the range of the reference spacing error, production continues and the current spacing error is stored.

[0012] An over-limit spacing error threshold is also set. When the difference between the current spacing error and the adjacent previously obtained spacing error is within the spacing error difference threshold range, the processing equipment will operate normally.

[0013] The threshold for the excessive spacing error is an experimental value.

[0014] The threshold value for the spacing error difference is an experimental value.

[0015] By acquiring the spacing error of multiple sets of workpieces, the difference in spacing error between two adjacent processing operations, and the qualification of the processed workpieces, the spacing error difference threshold and the over-limit spacing threshold are obtained.

[0016] Compared with the prior art, the present invention monitors the exposure accuracy of the workpiece before frontal exposure to avoid workpiece scrapping. At the same time, by setting a threshold for the difference in spacing error, the equipment operates more smoothly and the processing efficiency is improved. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the processing equipment of the present invention.

[0018] Figure 2 This is an enlarged schematic diagram of the auxiliary marker points and marking devices within the dashed box.

[0019] Figure 3 This is a flowchart of the first embodiment of the monitoring method.

[0020] Figure 4 This is a flowchart of the second embodiment of the monitoring method.

[0021] Figure 5 This is a flowchart of an optional implementation method for the monitoring method. Implementation

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be described below with reference to specific embodiments shown in the accompanying drawings.

[0023] like Figure 1-2 The processing equipment shown includes a control system, a motion platform 1, an image acquisition system 2, and a processing system 3. The control system controls the movements of the motion platform 1, the image acquisition system 2, and the processing system 3. The motion platform 1 carries the workpiece and moves it to the image acquisition system 2 and the processing system 3. The image acquisition system 2 acquires the alignment information of the workpiece, and the processing system 3 performs exposure processing on the workpiece.

[0024] The motion platform 1 includes a support platform 10 and a motion mechanism (not shown). The motion mechanism drives the support platform 10 to move. At least one edge of the support platform 10 is provided with a marking device 11 and an auxiliary positioning point 12. The marking device 11 and the auxiliary positioning point 12 are fixed in position on the support platform 10. When a workpiece is placed on the support platform 10, it covers the marking device 11. The auxiliary positioning point 12 is located outside the workpiece and can be grasped by the image acquisition system 2.

[0025] When exposing the front side of the inner layer plate, the image acquisition system 2 acquires the position of the auxiliary positioning point 12, and the marking device 11 forms an alignment point on the back side of the inner layer plate. By calculating the error between the actual coordinates and the theoretical coordinates of the auxiliary marking point 12, the actual positional relationship between the image acquisition system 2 and the auxiliary marking point 12 is obtained. Furthermore, by calculating the positional relationship between the image acquisition system 2 and the processing system 3, the actual positional relationship between the processing system 3 and the auxiliary marking point 12 is obtained. Based on this relationship, the positional parameters of the pattern to be exposed on the front side of the inner layer plate are adjusted to ensure that the positional relationship between the front pattern and the photolithographic markings on the back side of the inner layer plate remains unchanged.

[0026] The marking device 11 can also be in camera mode, capturing the texture information of the back of the workpiece as marking points.

[0027] During the production process, it was found that as the production and processing equipment is used for a longer period of time, the temperature of the equipment changes, and the environmental factors of the equipment change, which causes the platform supporting the workpiece to expand and contract, thus affecting the processing accuracy.

[0028] To monitor the operating status of the processing equipment and ensure processing accuracy, during the frontal exposure of the workpiece, the theoretical distance of the auxiliary marker points is first obtained, and a baseline spacing error threshold is set. During equipment operation, the actual measured distance of the auxiliary marker points is acquired. This measured distance is obtained by the image acquisition system during the exposure process, while the theoretical distance is the distance between the auxiliary marker points calibrated before the equipment processes the workpiece. The measured distance and theoretical distance refer to the straight-line distance between two auxiliary marker points. The spacing error is obtained by the difference between the measured distance and the theoretical distance between two auxiliary marker points. By comparing the spacing error with the set baseline spacing error threshold, the operating status of the double-sided processing equipment is determined. If it is within the threshold range, processing continues; if it exceeds the threshold range, production is interrupted for inspection to prevent insufficient equipment accuracy and thus scrapped parts.

[0029] The specific steps are as follows:

[0030] S1. Before processing the workpiece, obtain the theoretical distance of the auxiliary marker points and set the reference spacing error threshold.

[0031] S2. During the process of the workpiece passing through the image acquisition system, the image acquisition system acquires the actual position information of the auxiliary marker points respectively, and calculates the actual distance between the auxiliary marker points based on the actual position information;

[0032] S3. Compare the actual distance between the auxiliary markers with the theoretical distance between the corresponding auxiliary markers to obtain the difference between the two, which is the spacing error of the auxiliary markers.

[0033] S4. Compare the obtained spacing error with the reference spacing error threshold. If the spacing error is within the range of the reference spacing error threshold, the workpiece continues to move to the processing system for processing. If the spacing error exceeds the range of the reference spacing error threshold, an alarm is triggered and processing is stopped.

[0034] Repeat steps S2 to S4.

[0035] The theoretical distance between the auxiliary markers in step S1 is the theoretical distance between at least one pair of auxiliary markers. It can be the theoretical distance between a pair of auxiliary markers, the distance between multiple pairs of auxiliary markers, or all theoretical distances of any pair of auxiliary markers. The spacing error threshold is a data range of positive and negative numbers, or the spacing error threshold is a positive number.

[0036] In step S2, the actual distances of the auxiliary markers correspond to the theoretical distances in step S1. That is, the auxiliary markers used to calculate the actual distances in step S2 are the same as those used to obtain the theoretical distances in step S1. The number of actual distances obtained is the same as the number of theoretical distances, or multiple partial actual distances corresponding to theoretical distances can be obtained as needed. For example, if the processing accuracy requirements for different products differ, the number of actual distances obtained can be increased or decreased. Preferably, at least three auxiliary markers not on the same straight line are selected, and the distance between any two auxiliary markers is obtained, resulting in at least three actual distances and one theoretical distance.

[0037] In step S3, the spacing error is calculated according to the data format of the spacing error threshold. If the spacing error threshold is a data range, the difference between the actual distance and the theoretical distance is calculated directly. If the spacing error threshold is a positive number, the spacing error is the absolute value of the difference between the actual distance and the theoretical distance.

[0038] By using the above method, it is determined whether the machining cost will exceed the accuracy requirements before machining the front side of the workpiece, so as not to cause the workpiece to be scrapped, and at the same time to avoid wasting the front exposure time.

[0039] However, the above methods will cause the processing equipment to alarm and stop processing more frequently during the production process, resulting in frequent errors and seriously affecting production efficiency.

[0040] Research revealed that although the platform supporting the workpiece expanded and contracted, causing the spacing error to increase slowly and eventually exceed the set baseline spacing error threshold, the front exposure of the inner layer board acquired auxiliary marking points in real time. The auxiliary marking points and the marking device were in relatively fixed positions. The back exposure of the inner layer board was aligned based on the alignment points generated by the marking device. The front and back exposures of the inner layer board were synchronized, and the workpiece would not be scrapped immediately due to the spacing error exceeding the baseline spacing error threshold.

[0041] The difference between the spacing errors obtained in two adjacent processing steps is monitored by setting a spacing error difference threshold. The spacing error difference is obtained by comparing the spacing errors obtained in two adjacent processing steps. The difference between the two spacing errors is then compared with the set spacing error difference threshold. If the spacing error difference is within the threshold range, processing continues; if it exceeds the threshold range, production is interrupted.

[0042] Meanwhile, in order to prevent the spacing error from changing slowly and exceeding the maximum limit of the spacing error, an over-limit spacing error threshold is set based on the spacing error difference threshold.

[0043] During the processing, the equipment first obtains the spacing error and compares it with the previously stored spacing error of the previous processing to obtain the spacing error difference. It then determines whether the spacing error is within the range of the out-of-limit spacing error threshold and whether the spacing error difference is within the range of the spacing error difference threshold. If both results are within the range, processing continues. If any value exceeds the threshold range, production is interrupted.

[0044] The spacing error difference threshold and the over-limit spacing error threshold are experimental values ​​obtained through experiments. The spacing error difference threshold and the over-limit spacing threshold are obtained by acquiring the spacing error of multiple sets of workpieces, the spacing error difference between two adjacent processing operations, and detecting the qualification of the processed workpieces.

[0045] For newly started equipment, when processing the first workpiece, it is determined whether the spacing error exceeds the reference spacing error threshold. If it does not exceed the reference spacing error threshold, production continues and the current spacing error is stored. If it exceeds the reference spacing error threshold, production stops.

[0046] The processing steps are described below with reference to specific embodiments.

[0047] P1. Start the equipment. The image acquisition system acquires the actual position information of the auxiliary marker points corresponding to the first workpiece. Based on the actual position information of the auxiliary marker points, it acquires the first actual distance between at least one pair of auxiliary marker points.

[0048] P2. Based on the first actual distance and the corresponding ideal distance of the auxiliary marker point, obtain the first spacing error of the auxiliary marker point.

[0049] P3. Determine whether the first spacing error is within the reference spacing error threshold range. If the first spacing error is within the reference spacing error threshold range, store the first spacing error and continue processing; if it exceeds the reference spacing error threshold range, stop production.

[0050] P4. When the first spacing error is within the reference spacing error threshold range, the image acquisition system acquires the actual position information of the auxiliary marker points corresponding to the second workpiece, and acquires the second actual distance of at least one pair of auxiliary marker points based on the actual position information of the auxiliary marker points.

[0051] P5. Based on the second actual distance and the corresponding ideal distance of the auxiliary marker point, obtain the second spacing error of the auxiliary marker point.

[0052] P6. Determine whether the second spacing error is within the reference spacing error threshold range. If the second spacing error is within the reference spacing error threshold range, store the second spacing error and continue processing; if it exceeds the reference spacing error threshold range, proceed to step P7.

[0053] P7. Compare the second spacing error with the first spacing error to obtain the difference between them, and determine whether the difference is within the spacing error difference threshold range. If the difference is within the spacing error difference threshold range, then continue to determine whether the second spacing error is within the excessive spacing error threshold range. If the second spacing error is within the excessive spacing error threshold range, then store the second spacing error and continue processing; if the difference exceeds the spacing error difference threshold range or the second spacing error exceeds the excessive spacing error threshold range, then stop production.

[0054] Similarly, for cases where the spacing error exceeds the spacing error threshold, the actual position information of the auxiliary marker point corresponding to the Nth workpiece is obtained to get the Nth actual distance and the Nth spacing error. This is then compared with the previously stored (N-1)th spacing error to obtain the difference. It is then determined whether the difference is within the spacing error difference threshold range. If the difference is within the spacing error difference threshold range, the Nth spacing error is further determined to be within the excessive spacing error threshold range. If the Nth spacing error is within the excessive spacing error threshold range, the Nth spacing error is stored for judging the equipment status before processing the next workpiece.

[0055] The above implementation steps are merely exemplary, and those skilled in the art can make corresponding adjustments to the implementation steps according to the actual situation, such as... Figure 5As shown, the algorithm first determines whether the obtained spacing error exceeds the threshold range for excessive spacing errors. If the spacing error is within the threshold range, it further determines whether the difference between the current spacing error and the previously stored spacing error is within the threshold range for spacing error differences. The storage time for the current spacing error can be arbitrary, rather than being stored only after the determination is completed.

Claims

1. A monitoring method for a processing equipment, the processing equipment comprising a motion platform, an image acquisition system, and a processing system, wherein the motion platform carries a workpiece and moves it to the image acquisition system and the processing system, and at least one edge of the motion platform is provided with a plurality of auxiliary positioning points, wherein the auxiliary positioning points can be captured by the image acquisition system when the workpiece is placed on the motion platform, characterized in that: Before workpiece processing, at least one theoretical distance of auxiliary marker points is obtained, and a reference spacing error threshold and a spacing error difference threshold are set. During the operation of the workpiece driven by the motion platform, the image acquisition system obtains at least one actual measured distance of the auxiliary marker points corresponding to the theoretical distance, compares the actual measured distance with the corresponding theoretical distance to obtain the current spacing error, and compares it with the spacing error threshold to determine whether the workpiece can be processed by the processing system. If the current spacing error is within the reference spacing error threshold range, the current spacing error is stored and processing continues. If the current spacing error exceeds the reference spacing error threshold range, the current spacing error is compared with the adjacent previously obtained spacing error to obtain the spacing error difference. Based on whether the spacing error difference is within the spacing error difference threshold range, it is determined whether the processing equipment can continue processing.

2. A monitoring method for a processing equipment, the processing equipment comprising a motion platform, an image acquisition system, and a processing system, wherein the motion platform carries a workpiece and moves it to the image acquisition system and the processing system, and at least one edge of the motion platform is provided with a plurality of auxiliary positioning points, wherein the auxiliary positioning points can be captured by the image acquisition system when the workpiece is placed on the motion platform, characterized in that: Before workpiece processing, at least one theoretical distance of auxiliary marker points is obtained, and a reference spacing error threshold and a spacing error difference threshold are set. During the operation of the workpiece driven by the motion platform, the image acquisition system obtains at least one actual measured distance of the auxiliary marker points corresponding to the theoretical distance. The actual measured distance is compared with the corresponding theoretical distance to obtain the current spacing error. The current spacing error is compared with the adjacent previously obtained spacing error to obtain the spacing error difference. Based on whether the spacing error difference is within the spacing error difference threshold range, it is determined whether the processing equipment can continue processing.

3. The monitoring method for processing equipment according to claim 1 or 2, characterized in that: The theoretical distance is the calibration distance of the auxiliary marker point.

4. The monitoring method for processing equipment according to claim 3, characterized in that: The measured distance and calibration distance refer to the straight-line distance between two auxiliary marker points.

5. The monitoring method for processing equipment according to claim 1 or 2, characterized in that: When the motion platform has multiple auxiliary positioning points set on at least two platform edges, when obtaining the theoretical distance and the measured distance, at least three auxiliary marker points that are not on the same straight line are selected, and the distance between any two auxiliary marker points is obtained to obtain at least three actual distances and theoretical distances.

6. The monitoring method for processing equipment according to claim 1 or 2, characterized in that: An over-limit spacing error threshold is also set. When the difference between the current spacing error and the adjacent previously obtained spacing error is within the spacing error difference threshold range, the processing equipment will operate normally.

7. The monitoring method for processing equipment according to claim 6, characterized in that: The threshold for the excessive spacing error is an experimental value.

8. The monitoring method for processing equipment according to claim 1 or 2, characterized in that: The threshold value for the spacing error difference is an experimental value.

9. The monitoring method for processing equipment according to claim 7, characterized in that: By acquiring the spacing error of multiple sets of workpieces, the difference in spacing error between two adjacent processing operations, and the qualification of the processed workpieces, the spacing error difference threshold and the over-limit spacing threshold are obtained.

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