Roll-to-roll micro-patterning etching method for reinforcing metal sheets in flexible circuit boards

Abstract

This invention discloses a roll-to-roll micro-pattern etching method for reinforcing metal sheets in flexible printed circuit boards, relating to the field of reinforcing metal sheet etching technology. The method includes the following steps: dividing the strip into sections, and acquiring reflection signals of the reinforcing metal sheet within a certain time window at the outlet side of the spray etching chamber to obtain reflection data for each section window; performing data filtering to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, thus obtaining etched section reflection data; performing etching uniformity analysis and etching degree analysis based on the etched section reflection data to obtain section etching evaluation information; and adjusting the spray rate of the corresponding spray unit in the spray etching chamber based on the section etching evaluation information. This invention addresses the problem that existing reinforcing metal sheet etching technologies cannot divide the strip into sections and dynamically adjust the spray rate of the etching solution for each section based on the reflection of the reinforcing metal sheet surface when performing micro-pattern etching on reinforcing metal sheets.

Description

Technical Field

[0001] This invention relates to the field of etching technology for reinforcing metal sheets, specifically a roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards. Background Technology

[0002] Reinforcing metal sheet etching technology is a precision chemical etching processing technology for reinforcing metal sheets used in flexible electronic devices such as flexible printed circuit boards. It uses thin metal materials as substrates and combines mask forming with controlled chemical corrosion to achieve micro-patterns, precise dimensions and adaptability of reinforcing sheets. It is also a key process in the FPC industry chain to achieve lightweight, miniaturized and precise reinforcing sheets.

[0003] Existing etching technologies for reinforcing metal sheets often employ a fixed spray rate for the etching solution when etching fine patterns on reinforcing metal sheets in strips, in order to match the fixed transport speed of the strip. However, even within the same batch, mass-produced reinforcing metal coils inevitably exhibit slight differences in substrate composition. A fixed spray rate cannot accommodate these differences, easily leading to inconsistent etching levels. Areas with greater thickness require longer residence time of the etching solution, resulting in under-etching at a fixed speed; while areas with less thickness will be over-etched. For fine patterns, this deviation can directly lead to etching failure. Furthermore, slight local variations in the surface roughness and oxide layer thickness of the coil can cause inherent differences in etching rates, making a fixed spray rate insufficient. At low speeds, areas with thick oxide layers etch slowly, while areas without oxide layers etch quickly, resulting in uneven etching depths and making it difficult to guarantee the consistency of the finished product. Moreover, to accommodate material deviations in mass production, the fixed spray speed is often deliberately set to a high value to ensure that all areas are etched, which directly leads to the ineffective waste of resources. Furthermore, each time a product fails to meet etching standards, parameters often need to be manually adjusted repeatedly, resulting in high debugging costs. Therefore, existing reinforcing metal sheet etching technology cannot divide the strip into sections when performing micro-pattern etching on reinforcing metal sheets on the strip, and cannot dynamically adjust the spray speed of the etching solution for each section based on the reflection of the reinforcing metal sheet surface. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in the prior art. It involves dividing the strip into sections and collecting reflection signals from reinforcing metal sheets within a certain time window at the outlet side of the spray etching chamber to obtain reflection data for each section window. This data is then filtered to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, resulting in etched section reflection data. Furthermore, etching uniformity and etching degree analysis are performed to obtain section etching evaluation information. Based on this evaluation information, the spray rate of the corresponding spray unit in the spray etching chamber is adjusted. This addresses the problem that existing reinforcing metal sheet etching technologies cannot divide the strip into sections and dynamically adjust the spray rate of the etching solution for each section based on the reflection of the reinforcing metal sheet surface when performing micro-pattern etching on reinforcing metal sheets.

[0005] To achieve the above objectives, this application provides a roll-to-roll micro-pattern etching method for reinforcing metal sheets in flexible printed circuit boards, comprising the following steps:

[0006] The strip is divided into sections, and the reflection signal of the reinforcing metal sheet is collected within a certain time window at the exit side of the spray etching chamber to obtain the reflection data of the section window.

[0007] Data filtering processing is performed on the reflection data of the partitioned window to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, thus obtaining the reflection data of the etched partition.

[0008] Based on the etched partition reflection data, etch uniformity analysis and etch degree analysis are performed to obtain partition etch evaluation information;

[0009] Adjust the spray rate of the spray unit corresponding to the spray etching chamber based on the partitioned etching evaluation information.

[0010] Furthermore, the strip is divided into sections, and the reflection signal of the reinforcing metal sheet is collected within a certain time window at the exit side of the spray etching chamber to obtain the reflection data of the section window, including the following sub-steps:

[0011] The strip used to make the reinforcing metal sheet is called the reinforcing strip. The reinforcing strip is evenly divided into multiple parallel strip-shaped regions along the length of the reinforcing strip, which are called partition 1 to partition n, where n is the total number of partitions.

[0012] The spray etching chamber through which the reinforcing strip passes is called the etching chamber. On the exit side of the etching chamber, n identical industrial cameras are evenly arranged along the width direction of the strip, and each industrial camera only captures the image of each partition. The partitions 1 to n are sequentially labeled as acquisition devices 1 to acquisition devices n.

[0013] Furthermore, the strip is divided into sections, and the reflection signal of the reinforcing metal sheet is collected within a certain time window at the exit side of the spray etching chamber to obtain the reflection data of the section window, including the following sub-steps:

[0014] The reinforcing metal sheet that passes through the etching cavity on the reinforcing strip is denoted as the etched reinforcing sheet; the acquisition time window of the acquisition device is set to t0, and the first time interval is set to t1;

[0015] For any batch of synchronous etched reinforcement sheets, when the etched reinforcement sheets in partitions 1 to n are completely within the acquisition area of ​​the corresponding acquisition devices 1 to n, the grayscale images of the etched reinforcement sheets in their respective partitions are synchronously acquired at the first time interval within the acquisition time window, and recorded as the reflection image data of partitions 1 to n respectively.

[0016] Furthermore, dividing the strip into sections and acquiring the reflection signal of the reinforcing metal sheet within a certain time window at the exit side of the spray etching chamber to obtain the reflection data of the sectioned window also includes the following sub-steps:

[0017] For any image in the reflectance image data of partition 1, obtain the reflectance corresponding to each pixel in the image, and record it as point reflectance. After completion, the point reflectance information corresponding to the image is obtained. Repeat the process of obtaining the point reflectance information corresponding to each image to obtain the reflectance data of partition 1.

[0018] Repeatedly acquire the reflectance data corresponding to the synchronously acquired reflectance image data of partitions 2 to n to obtain the reflectance data of partitions 1 to n, which are denoted as partition window reflectance data;

[0019] The area on the qualified etched reinforcing sheet that has been etched is recorded as the etched area, and the area of ​​the reinforcing sheet strip that has not been etched is recorded as the background area.

[0020] The reflectance of the etched area and the background area were acquired using the same acquisition device and denoted as AR and BR respectively. The reflectance of the etched area before entering the etching cavity was also acquired and denoted as CR.

[0021] Further, the reflectance data of the partitioned window is filtered to obtain the reflectance of the etched area of ​​the reinforcing metal sheet, resulting in etched partition reflectance data, which includes the following sub-steps:

[0022] The currently collected partition window reflection data is recorded as the current reflection data, and the reflectivity information of any point collected in partition 1 in the current reflection data is recorded as the first reflectivity set.

[0023] Divide the first reflectivity set into two parts, one greater than (AR + BR) / 2 and the other not greater than (AR + BR) / 2. Then, use the 3σ principle to remove the outliers in each part respectively, and merge the remaining two parts, denoted as the second reflectivity set.

[0024] Denote [AR×k1, AR×k2] as the initial etching range and [BR×k1, BR×k2] as the initial background range. Screen the point reflectivities within the initial etching range and the initial background range from the second reflectivity set respectively to obtain the etching set and the background set, where k1 and k2 are set proportionality coefficients.

[0025] Further, the data screening process for the partition window reflection data to obtain the reflectivity of the reinforced metal sheet etching area and get the etched partition reflection data also includes the following sub-steps:

[0026] Calculate the averages of the etching set and the background set respectively, denoted as ASR and BSR, and calculate the standard deviations AG of the etching set and BG of the background set respectively; count the number of data within [ASR - 1.5×AG, ASR + 1.5×AG] and within [BSR - 1.5×BG, BSR + 1.5×BG] in the second reflectivity set respectively, and denote them as AF and BF in sequence;

[0027] Calculate AF / (AF + BF) and BF / (AF + BF) respectively, denoted as the etching weight QA and the background weight QB, and denote (ASR + BSR) / 2 as the initial median threshold AB0; calculate AB0 - QA×|ASR - BSR|×0.1 + QB×|ASR - BSR|×0.1, denoted as the corrected segmentation threshold AB1;

[0028] If AR > BR, mark the point reflectivities greater than AB1 in the first reflectivity set as etching reflectivities; if AR < BR, mark the point reflectivities less than AB1 in the first reflectivity set as etching reflectivities.

[0029] Further, the data screening process for the partition window reflection data to obtain the reflectivity of the reinforced metal sheet etching area and get the etched partition reflection data also includes the following sub-steps:

[0030] Screen all the etching reflectivities from the first reflectivity set, denoted as the initial etching set; and map all the etching reflectivities back to the pixel point coordinates in the corresponding image;

[0031] For any etching reflectivity, if there are no other etching reflectivities in its 8-neighborhood, mark it as an isolated noise point; repeat the screening of all the isolated noise points in the initial etching set and remove them to obtain the standard etching reflection information;

[0032] Repeatedly acquire all the etching reflection standard information of partition 1 in the current reflection data to obtain the etching reflection standard data of partition 1, and repeatedly acquire the etching reflection standard data of partitions 2 to n to obtain the etching partition reflection data.

[0033] Furthermore, the process of analyzing etching uniformity and etching degree based on the etched zone reflection data to obtain zone etching evaluation information includes the following sub-steps:

[0034] All etch reflection standard information in partition 1 is merged into a set, denoted as the first etch set. The mean HP and standard deviation HB of the first reflection set are calculated. The reflectance of any point in the first etch set is denoted as the first reflectance RE. The etch reflection standard information containing the first reflectance is denoted as the first standard information.

[0035] Calculate the mean FP and standard deviation FB of the first standard information; if the first reflectance is not located in [HP-k3×HB, HP+k3×HB] or not located in [FP-k3×FB, FP+k3×FB], it is marked as a suspected reflectance.

[0036] Furthermore, based on the etched zone reflection data, etch uniformity analysis and etch degree analysis are performed to obtain zone etch evaluation information, including the following sub-steps:

[0037] If the first reflectance is a suspected reflectance, then all the point reflectances of the first standard information are mapped back to the pixel coordinates in the corresponding image, and the k4 point reflectances closest to the first reflectance are obtained, which are denoted as the neighboring reflectances of the first reflectance, where k4 is the set number;

[0038] Calculate the mean of all neighboring reflectances, denoted as VP. If (|RE-VP| / VP)×100% is greater than k5, then mark the first reflectance as an abnormal reflectance and remove it. Repeat the removal of all abnormal reflectances in the first etch set to obtain the effective etch set, where k5 is the set threshold.

[0039] Calculate the mean ME and variance MF of the effective etch set, calculate |ME-CR| / |AR-CR|, denoted as the current etch severity coefficient of partition 1, and calculate MF / WF, denoted as the current etch stability coefficient of partition 1; where WF is the set variance threshold.

[0040] Repeatedly obtain the current etching degree coefficient and etching stability coefficient of all partitions to obtain partition etching evaluation information.

[0041] Furthermore, adjusting the spray rate of the spray unit corresponding to the spray etching chamber based on the partitioned etching evaluation information includes the following sub-steps:

[0042] The spray unit that acts on the etch reinforcement sheet in partition 1 in the etching chamber is denoted as the spray unit corresponding to partition 1. Repeatedly obtain the spray units corresponding to all partitions, and set the threshold range corresponding to the etching degree coefficient, denoted as [WE1, WE2].

[0043] If the etching degree coefficient of partition 1 is located in [WE1, WE2] and the etching stability coefficient is not greater than 1, then the etching degree of partition 1 is judged to be good.

[0044] If the etching degree coefficient of partition 1 is less than WE1, then the etching degree of partition 1 is determined to be insufficient, and the spraying speed of the corresponding spraying unit is increased.

[0045] If the etching degree coefficient of partition 1 is greater than WE2, then the etching degree of partition 1 is judged to be excessive, and the spraying speed of the corresponding spraying unit is reduced.

[0046] If the etching stability coefficient of partition 1 is greater than 1, it is determined that the etching uniformity is poor, and the spraying speed of the corresponding spraying unit is adjusted slightly.

[0047] Repeatedly synchronize all zones to make judgments and adjust the spraying speed of the spraying unit.

[0048] The beneficial effects of this invention are as follows: This invention divides the strip into sections and collects the reflection signal of the reinforcing metal sheet within a certain time window at the outlet side of the spray etching chamber to obtain the reflection data of the section window; it performs data filtering processing on the reflection data of the section window to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, thus obtaining the etched section reflection data; it performs etching uniformity analysis and etching degree analysis based on the etched section reflection data to obtain the section etching evaluation information; it adjusts the spray rate of the corresponding spray unit of the spray etching chamber based on the section etching evaluation information; when performing micro-pattern etching on the reinforcing metal sheet on the strip, the strip can be divided into sections, and the spray speed of the etching solution in each section can be dynamically adjusted according to the reflection of the surface of the reinforcing metal sheet, thereby improving the accuracy and uniformity of etching;

[0049] This invention improves the reliability of etching degree identification by setting a collection time window and collecting data for each partition multiple times within the window, followed by merging. This eliminates local single-point fluctuations caused by strip transmission vibration and camera acquisition noise. It first divides the data by (AR+BR) / 2 and then removes outliers, simultaneously handling outliers in both high-reflectivity and low-reflectivity sections, preventing mutual interference. It calculates the mean and standard deviation of the etching set and the background set, using data proportions as weighted thresholds instead of a fixed threshold for segmentation. This adapts to data offsets under different partitions, batches, or lighting conditions, improving accuracy. It first uses both overall and individual levels for dual judgment, marking suspected reflectivity; then, it uses the relative deviation from the mean of the neighborhood to judge and remove abnormal reflectivity, more accurately distinguishing between real process deviations and abnormal noise, avoiding misleading control by abnormal data. Attached Figure Description

[0050] Figure 1 This is a flowchart of the steps of the method of the present invention;

[0051] Figure 2 This is a schematic diagram of the partitioning of the strip material according to the present invention;

[0052] Figure 3 This is a flowchart of the process for obtaining the corrected segmentation threshold according to the present invention;

[0053] Figure 4 This is a schematic diagram of the electronic device of the present invention. Detailed Implementation

[0054] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] Example 1, please refer to Figure 1 As shown, this application provides a roll-to-roll micro-pattern etching method for reinforcing metal sheets in flexible circuit boards, comprising the following steps:

[0056] Step S1 involves partitioning the strip and acquiring the reflection signal of the reinforcing metal sheet within a certain time window at the exit side of the spray etching chamber to obtain the partitioned window reflection data. Step S1 includes the following sub-steps:

[0057] For step S101, please refer to... Figure 2As shown, the strip used to make the reinforcing metal sheet is referred to as the reinforcing strip. The reinforcing strip is evenly divided into multiple parallel strip-shaped regions along its length, which are referred to as partition 1 to partition n, where n is the total number of partitions. The reinforcing metal sheet, also known as the metal reinforcement sheet or metal support sheet, is a metal material that is attached to a specific area of ​​the flexible circuit board to enhance local rigidity, improve mechanical strength, improve heat dissipation, or achieve electromagnetic shielding, while maintaining the overall flexibility of the FPC.

[0058] In step S102, the spray etching chamber through which the reinforcing strip passes is referred to as the etching chamber. On the exit side of the etching chamber, n identical industrial cameras are uniformly arranged along the width direction of the strip, and each industrial camera only captures the image of each partition. The partitions are sequentially referred to as acquisition devices 1 to acquisition devices n in the order of partition 1 to partition n. Independent acquisition devices can avoid data confusion caused by insufficient resolution, perspective error or uneven lighting due to the large field of view of a single camera.

[0059] Step S103: The reinforcing metal sheet that passes through the etching cavity on the reinforcing strip is denoted as the etched reinforcing sheet; the acquisition time window of the acquisition device is set to t0, and the first time interval is set to t1; in this embodiment, t0=100ms, and the first time interval t1 is 20ms, that is, each partition acquires 5 images within a 100ms time window. The purpose of setting the acquisition time window and acquiring data multiple times within the window is to eliminate local single-point fluctuations caused by strip transmission vibration and camera acquisition noise. After merging the data acquired multiple times, the local signal fluctuations caused by strip transmission vibration can be eliminated, ensuring the reliability of the quantization results.

[0060] Step S104: For any batch of synchronous etched reinforcing sheets, i.e. etched reinforcing sheets that are etched in the etching cavity synchronously, when the etched reinforcing sheets in partitions 1 to n are completely entered into the acquisition area of ​​the corresponding acquisition device 1 to acquisition device n, the grayscale images of the etched reinforcing sheets in their respective partitions are synchronously acquired at the first time interval within the acquisition time window, and recorded as the reflection image data of partitions 1 to n respectively; the lighting conditions must remain unchanged when acquiring the images.

[0061] Step S105: For any image in the reflective image data of partition 1, obtain the reflectance corresponding to each pixel in the image, and record it as point reflectance. After completion, obtain the point reflectance information corresponding to the image. Repeat the acquisition of the point reflectance information corresponding to each image to obtain the reflectance data of partition 1. Point reflectance is a physical reflection intensity index that maps the gray level of image pixels. It is the basis for subsequent judgment of etched area and background area.

[0062] Step S106: Repeatedly acquire the reflectance data corresponding to the synchronously acquired reflectance image data of partitions 2 to n to obtain the reflectance data of partitions 1 to n, which are recorded as partition window reflectance data.

[0063] Step S107: The area on the qualified etched reinforcing sheet that has been etched is recorded as the etched area, and the area on the reinforcing sheet strip that has not been etched is recorded as the background area.

[0064] Step S108: Under the same acquisition device, acquire the reflectance of the etched area and the background area respectively, and ensure that the lighting conditions are the same. Record them as AR and BR in sequence. Acquire the reflectance of the etched area before entering the etching chamber, and record it as CR. The reflectance of the surface after the dry film is developed and before etching. AR, BR and CR are typical reflectances under normal conditions and are the benchmarks for post-processing. CR is the benchmark used to measure the change in reflection before and after etching and to calculate the relative degree of etching.

[0065] In the specific implementation process, the reflectivity of the strip surface during etching is strongly correlated with the degree of metal etching. The reflectivity of the dry film covered area is the baseline value, while the reflectivity of the exposed metal etched area changes in a gradient with the increase of etching depth. The uneven etching of different areas of the strip banner will directly result in significant differences in the mean and variance of the reflected signal at different positions of the banner.

[0066] Step S2 involves filtering the reflection data of the partitioned window to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, thus obtaining the etched partition reflection data. Step S2 includes the following sub-steps:

[0067] Step S201: Record the currently collected partition window reflection data as the current reflection data, and record the reflectivity information of any point collected in partition 1 in the current reflection data as the first reflectivity set;

[0068] For step S202, please refer to... Figure 3 As shown, the first reflectance set is divided into two parts: one greater than (AR+BR) / 2 and the other not greater than (AR+BR) / 2. Outliers are removed from each part using the 3σ principle. The remaining two parts are then merged and denoted as the second reflectance set. Dividing the data into half that is biased towards high reflectance and half that is biased towards low reflectance allows for the separate statistical removal of outliers from samples that may belong to the two categories, avoiding mutual interference between the two parts. When industrial cameras collect data, pixel-level isolated extreme noise may be mixed in. This type of noise deviates greatly from AR and BR, has no technological significance, and will interfere with subsequent clustering and threshold calculation, so it needs to be removed first.

[0069] Step S203: Denote [AR×k1, AR×k2] as the initial etching range and [BR×k1, BR×k2] as the initial background range. Screen the point reflectances within the initial etching range and the initial background range from the second reflectance collection respectively to obtain the etching collection and the background collection. Here, k1 and k2 are set proportionality coefficients. In this embodiment, k1 = 0.9, k2 = 1.1, k1 < 1, 1 < k2, and they can be appropriately fine-tuned.

[0070] AR and BR are typical reflectances calibrated in experiments. In actual production, there will be slight offsets due to dry film batches, etching solution concentrations, and substrate surface conditions. If AR and BR are directly used as thresholds, it will lead to deviations when screening the reflectances of the etching area subsequently; the initial etching range and the initial background range are to adapt to the slight process offsets of AR and BR, which can not only ensure screening out the reflectances of the corresponding etching area and background area from the second reflectance collection, but also prevent over-expanding the range and causing pixel crossover mixing between the two types of areas.

[0071] Step S204: Calculate the averages of the etching collection and the background collection respectively, denoted as ASR and BSR, and calculate the standard deviations AG of the etching collection and BG of the background collection respectively; count the number of data within [ASR - 1.5×AG, ASR + 1.5×AG] and within [BSR - 1.5×BG, BSR + 1.5×BG] in the second reflectance collection in sequence, denoted as AF and BF respectively; the standard deviations ASR and BSR reflect the actual dispersion degrees of the reflectances of the two types of areas, and 1.5 times the standard deviation can enclose most of the core pixels in the collection, which can not only eliminate the slightly dispersed pixels in the collection but also ensure that the statistic of the core pixels is sufficient.

[0072] Step S205: Calculate AF / (AF + BF) and BF / (AF + BF) respectively, denoted as the etching weight QA and the background weight QB, and denote (ASR + BSR) / 2 as the initial median threshold AB0; calculate AB0 - QA×|ASR - BSR|×0.1 + QB×|ASR - BSR|×0.1, denoted as the corrected segmentation threshold AB1; multiplying by 0.1 is to compress the correction amount to 1 / 10 of the original, that is, to set an upper limit for the correction amount, so that the correction is only used to offset the segmentation deviation caused by the pixel ratio difference, rather than making the threshold deviate too much from the initial median threshold due to a large basic difference and causing new misjudgments.

[0073] Calculate the weights through the proportion of core pixels to generate the adaptive weighted segmentation threshold AB1, which makes the threshold AB1 slightly shift towards the area with less pixel proportion, reducing the misjudgment of the edge pixels in the area with a large proportion, and can achieve accurate segmentation of the two types of areas.

[0074] For example, the second reflectivity set is {82, 84, 85, 83, 61, 60, 59, 62, 95, 48, 86, 81, 63, 58, 80}, with the unit of %, AR = 85%, BR = 60%; then the initial etching range is [76.5, 93.5], and the initial background range is [54, 66]; then the etching set is {80, 81, 82, 83, 84, 85, 86}, and the background set is {58, 59, 60, 61, 62, 63};

[0075] Then ASR = 83%, BSR = 60.5%, AG = 2%, BG = 1.708%, then [ASR - 1.5×AG, ASR + 1.5×AG] is [80, 86], [BSR - 1.5×BG, BSR + 1.5×BG] is [57.93, 63.06], then the corresponding numbers are 7 and 6 respectively, then QA = 0.539, QB = 0.461, then AB1 = 71.58%;

[0076] Step S206, if AR > BR, then mark the point reflectivity greater than AB1 in the first reflectivity set as the etching reflectivity; if AR < BR, then mark the point reflectivity less than AB1 in the first reflectivity set as the etching reflectivity.

[0077] Step S207, screen out all the etching reflectivities from the first reflectivity set, denoted as the initial etching set; and map all the etching reflectivities back to the pixel point coordinates in the corresponding image; [[ID=X]]

[0078] Step S208, for any etching reflectivity, if there is no other etching reflectivity in its 8-neighborhood, then mark it as an isolated noise point; repeat to screen out all the isolated noise points in the initial etching set and remove them to obtain the standard etching reflection information; there must be at least 1 other etching reflectivity in the 8-neighborhood of the etching reflectivity in the normal etching area, if not, it means that the etching reflectivity is misjudged due to the close numerical value.

[0079] Step S209, repeatedly obtain all the standard etching reflection information in partition 1 of the current reflection data to get the standard etching reflection data of partition 1, and repeatedly obtain the standard etching reflection data of partitions 2 to n to get the partitioned etching reflection data;

[0080] In the specific implementation process, there will be a small number of misjudgments only by correcting the segmentation threshold AB1. For example, the reflectivity of the dry film scratch in the unetched area is numerically close to that in the etched area and is misclassified. The etched area of the reinforcing metal sheet is a continuous surface area physically without isolation. Through the spatial connectivity verification of the 8-neighborhood, the isolated points with numerical misjudgments are removed to make the reflectivity data of the extracted etched area more accurate.

[0081] Step S3 involves performing etching uniformity and etching degree analysis based on the etching zone reflection data to obtain zone etching evaluation information. Step S3 includes the following sub-steps:

[0082] Step S301: Merge all the etch reflection standard information of partition 1 into a set, denoted as the first etch set, and calculate the mean HP and standard deviation HB of the first reflection set; denote the reflectivity of any point in the first etch set as the first reflectivity RE, and denote the etch reflection standard information where the first reflectivity is located as the first standard information.

[0083] Step S302: Calculate the mean FP and standard deviation FB of the first standard information; if the first reflectance is not located in [HP-k3×HB, HP+k3×HB] or not located in [FP-k3×FB, FP+k3×FB], it is marked as a suspected reflectance;

[0084] [HP-k3×HB, HP+k3×HB] is a globally unified normal judgment standard, reflecting the global statistical characteristics of the reflectivity of the etched area within a short time window; [FP-k3×FB, FP+k3×FB] is a normal judgment standard for data acquired in a single acquisition, reflecting the statistical characteristics of that acquisition. Because all etch reflection standard information is obtained from multiple acquisitions within the acquisition time window, there may be slight statistical differences in each acquisition. If only the global benchmark is used for judgment, the normal difference in a single acquisition will be misjudged as abnormal.

[0085] Step S303: If the first reflectance is a suspected reflectance, then all the point reflectances of the first standard information are mapped back to the pixel coordinates in the corresponding image, and the k4 point reflectances closest to the first reflectance are obtained, denoted as the neighboring reflectances of the first reflectance, where k4 is the set number; in this embodiment, k4=8, which can be flexibly set, generally [8, 20]; suspected reflectances may also mark some edge or slightly changing suspected reflectances as suspected anomalies; normal reflectances and neighboring reflectances are basically the same size, while the values ​​of real anomaly points are usually isolated in the neighborhood, and spatial continuity can be further confirmed by using the neighborhood mean:

[0086] Step S304: Calculate the mean of all neighboring reflectivities, denoted as VP. If (|RE-VP| / VP)×100% is greater than k5, then the first reflectivity is marked as an abnormal reflectivity and removed. Repeat the removal of all abnormal reflectivities in the first etching set to obtain the effective etching set, where k5 is the set threshold. In this embodiment, k5=20%, which can be set according to AR and BR. Generally, it is the absolute difference between AR and BR, which can be adjusted flexibly.

[0087] Step S305: Calculate the mean ME and variance MF of the effective etch set, calculate |ME-CR| / |AR-CR|, denoted as the current etch severity coefficient of partition 1, and calculate MF / WF, denoted as the current etch stability coefficient of partition 1; where WF is the set variance threshold.

[0088] Step S306: Repeatedly obtain the current etching degree coefficient and etching stability coefficient of all partitions to obtain partition etching evaluation information;

[0089] In practice, a single global approach may not be sensitive to anomalies in a single data collection; while looking only at the statistics of a single data collection may ignore anomalies in the global context. Dual judgment can capture both global anomalies and single-data collection anomalies at the same time, ensuring the accuracy and reliability of subsequent calculations.

[0090] Step S4: Adjust the spray rate of the spray unit corresponding to the spray etching chamber according to the partitioned etching evaluation information; Step S4 includes the following sub-steps:

[0091] Step S401: The spray unit that acts on the etch reinforcement sheet of partition 1 in the etching chamber is recorded as the spray unit corresponding to partition 1. The spray units corresponding to all partitions are repeatedly obtained. The threshold range corresponding to the etching degree coefficient is set as [WE1, WE2].

[0092] Step S402: If the etching degree coefficient of partition 1 is located in [WE1, WE2] and the etching stability coefficient is not greater than 1, then the etching degree of partition 1 is determined to be good.

[0093] Step S403: If the etching degree coefficient of partition 1 is less than WE1, it is determined that the etching degree of partition 1 is insufficient, and the spraying speed of the corresponding spraying unit is increased, that is, the etching rate is accelerated.

[0094] Step S404: If the etching degree coefficient of partition 1 is greater than WE2, it is determined that the etching degree of partition 1 exceeds the standard, and the spraying speed of the corresponding spraying unit is reduced, that is, the etching rate is slowed down. In roll-to-roll etching, the overall transmission speed is a constant tension reference and generally cannot be adjusted in a regional manner. Therefore, the core of regional speed regulation is to adjust the spraying speed.

[0095] Step S405: If the etching stability coefficient of partition 1 is greater than 1, it is determined that the etching uniformity is poor. Then, the spraying speed of the corresponding spraying unit is adjusted slightly back and forth. By changing the spraying speed slightly back and forth, the local flow field state of the etchant in the etching area is changed, eliminating the problem of excessively high local flow velocity in the dead corner of the flow field, so that the contact and renewal of the etchant with the strip surface is more uniform. The magnitude of the back and forth adjustment can be flexibly set according to the actual application scenario.

[0096] Step S406: Repeat the synchronous judgment of all zones and adjust the spraying speed of the spraying unit.

[0097] In the specific implementation process, if a certain area simultaneously meets the conditions of insufficient etching degree and poor etching uniformity, or excessive etching degree and poor etching uniformity, the spraying speed should be adjusted first according to the etching degree, and then adjusted back and forth slightly during the speed adjustment.

[0098] Example 2, please refer to Figure 4 As shown, Figure 4 A schematic diagram of an electronic device is provided, which may include a processor, a communication interface, a memory, and a communication bus. The processor, communication interface, and memory communicate with each other via the communication bus. The memory stores computer-readable instructions, and the processor can call these instructions. When the processor executes a computer-readable instruction, it performs steps such as those in a roll-to-roll micro-pattern etching method for reinforcing metal sheets in flexible circuit boards to achieve the following functions: partitioning the strip and acquiring reflection signals of the reinforcing metal sheet within a certain time window at the exit side of the spray etching chamber to obtain partition window reflection data; performing data filtering on the partition window reflection data to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, thus obtaining etch partition reflection data; performing etching uniformity analysis and etching degree analysis based on the etch partition reflection data to obtain partition etching evaluation information; and adjusting the spray rate of the corresponding spray unit in the spray etching chamber based on the partition etching evaluation information.

[0099] Furthermore, when the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0100] Example 3: This application also provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program performs steps such as those in the roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards to achieve the following functions: partitioning the strip and acquiring reflection signals of the reinforcing metal sheet within a certain time window at the exit side of the spray etching chamber to obtain partition window reflection data; performing data filtering processing on the partition window reflection data to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, thus obtaining etch partition reflection data; performing etching uniformity analysis and etching degree analysis based on the etch partition reflection data to obtain partition etching evaluation information; and adjusting the spray rate of the spray unit corresponding to the spray etching chamber based on the partition etching evaluation information.

[0101] Based on the above description of the embodiments, the embodiments of the present invention can be provided as methods, systems, or computer program products. Based on this understanding, the above technical solutions, in essence or in terms of their contribution to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or certain parts of the embodiments.

[0102] In the embodiments provided in this application, it should be understood that the disclosed system or method can be implemented in other ways. The embodiments described above are merely illustrative. For example, the division of modules or units is only a logical functional division, and there may be other division methods in actual implementation. Furthermore, multiple modules or units may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the coupling or direct coupling or communication connection shown or discussed may be through some communication interfaces. The indirect coupling or communication connection between systems, modules, and units may be electrical, mechanical, or other forms.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A roll-to-roll micro-pattern etching method for reinforcing metal sheets in flexible circuit boards, characterized in that, Includes the following steps: The strip is divided into sections, and the reflection signal of the reinforcing metal sheet is collected within a certain time window at the exit side of the spray etching chamber to obtain the reflection data of the section window. Data filtering processing is performed on the reflection data of the partitioned window to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, thus obtaining the reflection data of the etched partition. Based on the etched partition reflection data, etch uniformity analysis and etch degree analysis are performed to obtain partition etch evaluation information; Adjust the spray rate of the spray unit corresponding to the spray etching chamber based on the partitioned etching evaluation information; The strip is divided into sections, and the reflection signal of the reinforcing metal sheet is collected within a certain time window at the exit side of the spray etching chamber to obtain the reflection data of the section window, including the following sub-steps: The strip used to make the reinforcing metal sheet is called the reinforcing strip. The reinforcing strip is evenly divided into multiple parallel strip-shaped regions along the length of the reinforcing strip, which are called partition 1 to partition n, where n is the total number of partitions. The spray etching chamber through which the reinforcing strip passes is called the etching chamber. On the exit side of the etching chamber, n identical industrial cameras are evenly arranged along the width direction of the strip, and each industrial camera only captures the image of each partition. The partitions 1 to n are sequentially denoted as acquisition devices 1 to acquisition devices n. The reinforcing metal sheet that passes through the etching cavity on the reinforcing strip is denoted as the etched reinforcing sheet; the acquisition time window of the acquisition device is set to t0, and the first time interval is set to t1; For any batch of synchronous etched reinforcement sheets, when the etched reinforcement sheets in partitions 1 to n are completely within the acquisition area of ​​the corresponding acquisition devices 1 to n, the grayscale images of the etched reinforcement sheets in their respective partitions are synchronously acquired at the first time interval within the acquisition time window, and recorded as the reflection image data of partitions 1 to n respectively.

2. The roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards according to claim 1, characterized in that, The process of dividing the strip into sections and acquiring the reflection signal of the reinforcing metal sheet within a certain time window at the exit side of the spray etching chamber to obtain the reflection data of the section window also includes the following sub-steps: For any image in the reflectance image data of partition 1, obtain the reflectance corresponding to each pixel in the image, and record it as point reflectance. After completion, the point reflectance information corresponding to the image is obtained. Repeat the process of obtaining the point reflectance information corresponding to each image to obtain the reflectance data of partition 1. Repeatedly acquire the reflectance data corresponding to the synchronously acquired reflectance image data of partitions 2 to n to obtain the reflectance data of partitions 1 to n, which are denoted as partition window reflectance data; The area on the qualified etched reinforcing sheet that has been etched is recorded as the etched area, and the area of ​​the reinforcing sheet strip that has not been etched is recorded as the background area. The reflectance of the etched area and the background area were acquired using the same acquisition device and denoted as AR and BR respectively. The reflectance of the etched area before entering the etching cavity was also acquired and denoted as CR.

3. The roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards according to claim 2, characterized in that, The process of filtering and processing the reflection data of the partitioned window to obtain the reflectivity of the etched area of ​​the reinforcing metal sheet, resulting in the etched partition reflection data, includes the following sub-steps: Record the reflected data of the currently collected partition window as the current reflected data, and record the point reflectivity information collected at any time in partition 1 of the current reflected data as the first reflectivity set; Divide the first reflectivity set into two parts, one part greater than (AR + BR) / 2 and the other part not greater than (AR + BR) / 2, and use the 3σ principle to剔除 the outliers in each part respectively, and then merge the remaining two parts, which is recorded as the second reflectivity set; Record [AR×k1, AR×k2] as the initial etching range, and record [BR×k1, BR×k2] as the initial background range. Screen the point reflectivities within the initial etching range and the initial background range from the second reflectivity set respectively to obtain the etching set and the background set, where k1 and k2 are set proportionality coefficients.

4. The roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards according to claim 3, characterized in that, The data screening process for the reflected data of the partition window to obtain the reflectivity of the reinforced metal sheet etching area and obtain the etched partition reflected data further includes the following sub-steps: Calculate the average values of the etching set and the background set respectively, which are recorded as ASR and BSR, and calculate the standard deviations AG of the etching set and BG of the background set respectively; count the number of data in the second reflectivity set within [ASR - 1.5×AG, ASR + 1.5×AG] and within [BSR - 1.5×BG, BSR + 1.5×BG] respectively, and record them in order as AF and BF; Calculate AF / (AF + BF) and BF / (AF + BF) respectively, which are recorded as the etching weight QA and the background weight QB, and record (ASR + BSR) / 2 as the initial median threshold AB0; calculate AB0 - QA×|ASR - BSR|×0.1 + QB×|ASR - BSR|×0.1, which is recorded as the corrected segmentation threshold AB1; If AR > BR, mark the point reflectivities greater than AB1 in the first reflectivity set as etching reflectivities; if AR < BR, mark the point reflectivities less than AB1 in the first reflectivity set as etching reflectivities.

5. The roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards according to claim 4, characterized in that, The data screening process for the reflected data of the partition window to obtain the reflectivity of the reinforced metal sheet etching area and obtain the etched partition reflected data further includes the following sub-steps: Screen all the etching reflectivities from the first reflectivity set, which is recorded as the initial etching set; and map all the etching reflectivities back to the pixel point coordinates in the corresponding image; For any etching reflectivity, if there are no other etching reflectivities in its 8-neighborhood, mark it as an isolated noise point; repeat the screening of all the isolated noise points in the initial etching set and剔除 them to obtain the standard etching reflection information; Repeat to obtain all the standard etching reflection information in partition 1 of the current reflected data to obtain the standard etching reflection data of partition 1, and repeat to obtain the standard etching reflection data of partitions 2 to n to obtain the etched partition reflected data.

6. The roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards according to claim 5, characterized in that, According to the etched partition reflected data, perform etching uniformity analysis and etching degree analysis to obtain the partition etching evaluation information further includes the following sub-steps: All etch reflection standard information in partition 1 is merged into a set, denoted as the first etch set. The mean HP and standard deviation HB of the first reflection set are calculated. The reflectance of any point in the first etch set is denoted as the first reflectance RE. The etch reflection standard information containing the first reflectance is denoted as the first standard information. Calculate the mean FP and standard deviation FB of the first standard information; if the first reflectance is not located in [HP-k3×HB, HP+k3×HB] or not located in [FP-k3×FB, FP+k3×FB], it is marked as a suspected reflectance.

7. The roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards according to claim 6, characterized in that, Based on the etched zone reflection data, etch uniformity analysis and etch degree analysis are performed to obtain zone etch evaluation information, including the following sub-steps: If the first reflectance is a suspected reflectance, then all the point reflectances of the first standard information are mapped back to the pixel coordinates in the corresponding image, and the k4 point reflectances closest to the first reflectance are obtained, which are denoted as the neighboring reflectances of the first reflectance, where k4 is the set number; Calculate the mean of all neighboring reflectances, denoted as VP. If (|RE-VP| / VP)×100% is greater than k5, then mark the first reflectance as an abnormal reflectance and remove it. Repeat the removal of all abnormal reflectances in the first etch set to obtain the effective etch set, where k5 is the set threshold. Calculate the mean ME and variance MF of the effective etch set, calculate |ME-CR| / |AR-CR|, denoted as the current etch severity coefficient of partition 1, and calculate MF / WF, denoted as the current etch stability coefficient of partition 1; where WF is the set variance threshold. Repeatedly obtain the current etching degree coefficient and etching stability coefficient of all partitions to obtain partition etching evaluation information.

8. The roll-to-roll micro-pattern etching method for reinforcing metal sheets of flexible circuit boards according to claim 7, characterized in that, Adjusting the spray rate of the spray unit corresponding to the spray etching chamber based on the partitioned etching evaluation information includes the following sub-steps: The spray unit that acts on the etch reinforcement sheet in partition 1 in the etching chamber is denoted as the spray unit corresponding to partition 1. Repeatedly obtain the spray units corresponding to all partitions, and set the threshold range corresponding to the etching degree coefficient, denoted as [WE1, WE2]. If the etching degree coefficient of partition 1 is located in [WE1, WE2] and the etching stability coefficient is not greater than 1, then the etching degree of partition 1 is judged to be good. If the etching degree coefficient of partition 1 is less than WE1, then the etching degree of partition 1 is determined to be insufficient, and the spraying speed of the corresponding spraying unit is increased. If the etching degree coefficient of partition 1 is greater than WE2, then the etching degree of partition 1 is judged to be excessive, and the spraying speed of the corresponding spraying unit is reduced. If the etching stability coefficient of partition 1 is greater than 1, it is determined that the etching uniformity is poor, and the spraying speed of the corresponding spraying unit is adjusted slightly. Repeatedly synchronize all zones to make judgments and adjust the spraying speed of the spraying unit.

Images