High-precision machining method for millimeter wave radar circuit board

Abstract

The invention relates to the technical field of automobile circuit boards, in particular to a millimeter wave radar circuit board high-precision machining method which comprises the steps that a substrate and a radio frequency circuit are determined; line multiplication compensation is determined, and a radio frequency circuit is transferred and etched; performing laser drilling; filling holes and electroplating; performing surface protection treatment to obtain a prepared circuit board; determining an average deviation value; and determining whether the processing of the circuit board is qualified based on the average deviation value, identifying abnormal point locations in the preset detection point locations when the processing of the circuit board is determined to be abnormal, and adjusting processing parameters of the circuit board based on the abnormal point location proportion. According to the detected circuit condition of the circuit board, the processing technology is adjusted in time when it is determined that preparation of the circuit board is abnormal, and the preparation efficiency of the circuit board is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive circuit boards, and particularly to a high-precision processing method for millimeter-wave radar circuit boards. Background Art

[0002] An autonomous vehicle, also known as a driverless vehicle or a computer-driven vehicle, realizes driverless operation through a computer system. Its computer system requires a large number of sensors and complex circuits. Among them, millimeter-wave radar has become the mainstream sensor for autonomous driving because it has a long transmission distance, high signal accuracy, and better performance than sensors such as infrared, laser, ultrasonic, and cameras. The frequency bands of millimeter-wave radar are 24 GHz and 77 GHz. Among them, the 77 GHz millimeter-wave radar is used as a sensor for forward long-range detection of vehicles, and the 24 GHz millimeter-wave radar is used for short-range detection of the rear and sides. The existing circuit boards required for 77 GHz millimeter-wave radar use polytetrafluoroethylene glass cloth copper-clad laminates.

[0003] Millimeter-wave radar is crucial in the autonomous driving system, and the processing accuracy of its circuit board directly affects the radar performance.

[0004] Chinese Patent Application Publication No.: CN119767559A discloses a processing method for a millimeter-wave radar circuit board, which uses continuous blind vias to replace multiple independent blind hole structures in the traditional structure. Thus, a continuous radio frequency circuit pattern can be formed, and multiple electroplating, single-sided copper reduction, and circuit etching processes in the traditional processing method are cancelled. The outer layer circuit, the first copper layer, and the second copper layer can be directly made through activation and copper deposition. It can be seen that the above technical solution has the following problems: it does not consider adjusting the processing technology in a timely manner according to the circuit conditions of the detected circuit board when determining that the preparation of the circuit board is abnormal, which affects the preparation efficiency of the circuit board. Summary of the Invention

[0005] Therefore, the present invention provides a high-precision processing method for a millimeter-wave radar circuit board to overcome the problem in the prior art that the processing technology is not adjusted in a timely manner according to the circuit conditions of the detected circuit board when determining that the preparation of the circuit board is abnormal, which affects the preparation efficiency of the circuit board.

[0006] To achieve the above object, the present invention provides a high-precision processing method for a millimeter-wave radar circuit board, including: S1, determining a substrate and a radio frequency circuit; S2, determining line multiplication compensation, transferring and etching the radio frequency circuit; S3, laser drilling; S4, filling holes with electroplating; S5, surface protection treatment to obtain a completed prepared circuit board; S6, determining the average deviation amount based on the image information of the obtained completed prepared circuit board; S7. Determine whether the processing of the circuit board is qualified based on the average deviation amount, including: Determine that the processing of the circuit board is abnormal, identify the abnormal points among the preset detection points, and adjust the processing parameters of the circuit board based on the proportion of abnormal points, including adjusting the line multiplication compensation to the corresponding value, adjusting the laser scanning speed during the laser drilling process to the corresponding value, or adjusting the number of ventilation holes during the laser drilling process to the corresponding value; Or, determine that the processing of the circuit board is qualified, and continue to use the current processing parameters to complete the processing of each circuit board.

[0007] Further, the process of determining the average deviation amount based on the obtained image information of the completed circuit board includes: Perform image detection on the processed circuit board, obtain image information, and obtain the actual line width of the circuit at each preset detection point; Calculate the absolute value of the difference between each actual line width and the corresponding preset line width to obtain the deviation value of the corresponding preset detection point; Solve the average value of each deviation value to obtain the average deviation amount; The process of determining whether the processing of the circuit board is qualified based on the average deviation amount includes: If the average deviation amount is less than or equal to the first preset average deviation amount, determine that the processing of the circuit board is qualified, and continue to use the current processing parameters to complete the processing of each circuit board; If the average deviation amount is less than or equal to the second preset average deviation amount and greater than the first preset average deviation amount, determine whether the processing of the circuit board is qualified in combination with the average line width; If the average deviation amount is greater than the second preset average deviation amount, determine that the processing of the circuit board is abnormal, identify the abnormal points among the preset detection points, and adjust the processing parameters of the circuit board based on the proportion of abnormal points.

[0008] Further, determining whether the processing of the circuit board is qualified in combination with the average line width includes: Solve the average value of the actual line widths of the circuits at each preset detection point to obtain the average line width; If the average line width is less than or equal to the first preset average line width, determine that the processing of the circuit board is abnormal, identify the abnormal points among the preset detection points, and adjust the processing parameters of the circuit board based on the proportion of abnormal points; If the average line width is less than or equal to the second preset average line width and greater than the first preset average line width, determine whether the processing of the circuit board is qualified based on the average etching angle deviation; If the average line width is greater than the second preset average line width, adjust the first preset average deviation amount to the corresponding value based on the line width difference amount.

[0009] Further, the process of determining whether the processing of the circuit board is qualified based on the average etching angle deviation includes: Obtain the actual angles between the sides and the bottom surfaces of the lines at each preset detection point; Calculate the difference between each actual angle and the corresponding preset side etching angle to obtain the etching angle difference; Solve the average value of the etching angle differences at each preset detection point to obtain the average etching angle deviation; If the average etching angle deviation is less than or equal to the preset etching angle deviation, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continuously used to complete the processing of each circuit board; If the average etching angle deviation is greater than the preset etching angle deviation, it is determined that the processing of the circuit board is abnormal, identify the abnormal points among each preset detection point, and adjust the processing parameters of the circuit board based on the proportion of the abnormal points.

[0010] Further, the first preset average deviation amount is adjusted to the corresponding value based on the line width difference amount, where Record the difference between the average line width and the second preset average line width as the line width difference amount; The increase amplitude of the first preset average deviation amount is proportional to the line width difference amount.

[0011] Further, the process of identifying the abnormal points among each preset detection point includes: Compare the deviation value of each preset detection point with the first preset average deviation amount one by one; Mark the preset detection points with deviation values greater than the first preset average deviation amount as abnormal points; The process of adjusting the processing parameters of the circuit board based on the proportion of the abnormal points includes: Solve the ratio of the number of statistically abnormal points to the total number of each preset detection point to obtain the proportion of the abnormal points; If the proportion of the abnormal points is less than or equal to the preset proportion of the abnormal points, adjust the number of ventilation holes in the electroplating frame during the S4 hole filling electroplating process to the corresponding value based on the abnormal point distribution parameter; If the proportion of the abnormal points is greater than the preset proportion of the abnormal points, adjust the processing parameters of the circuit board based on the proportion of the types of the abnormal points.

[0012] Further, the number of ventilation holes is adjusted to the corresponding value based on the abnormal point distribution parameter, where Obtain the distances between each abnormal point, solve the average value of each distance to obtain the abnormal point distribution parameter; The increase amplitude of the number of ventilation holes is proportional to the abnormal point distribution parameter.

[0013] Further, adjusting the processing parameters of the circuit board based on the proportion of the types of the abnormal points includes: Obtain the types corresponding to the abnormal points, where the types include lines and drill holes; Respectively record the number of abnormal points with the type of line in the statistics as the number of abnormal lines, and record the number of abnormal points with the type of drill hole as the number of abnormal drill holes; If the number of abnormal lines is greater than or equal to the number of abnormal drill holes, adjust the line multiplication compensation to the corresponding value based on the number of abnormal lines; If the number of abnormal lines is less than the number of abnormal drill holes, adjust the laser scanning speed during the laser drilling process to the corresponding value based on the average difference.

[0014] Further, adjust the laser scanning speed during the laser drilling process to the corresponding value based on the average difference, where, Solve the difference between the average deviation and the second preset average deviation to obtain the average difference; The reduction amplitude of the laser scanning speed is proportional to the average difference.

[0015] Further, adjust the line multiplication compensation to the corresponding value based on the number of abnormal lines, where, The increase amplitude of the line multiplication compensation is proportional to the number of abnormal lines.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows. Whether the processing of the circuit board is qualified is determined based on the average deviation amount. The average deviation amount characterizes the error situation of the circuit board. When the average deviation amount is less than or equal to the first preset average deviation amount, the circuit processing accuracy is high, the deviation is within an acceptable range, and the performance requirements of the millimeter-wave radar are met. This ensures the quality and performance stability of the circuit board. When the average deviation amount is less than or equal to the second preset average deviation amount and greater than the first preset average deviation amount, further determination is made in combination with the average line width. When the average line width is less than or equal to the first preset average line width, the average line width is too small, which will affect the resistance and signal transmission ability of the circuit, resulting in a decline in the performance of the circuit board. In this case, it is determined that the processing of the circuit board is abnormal, and problems in the circuit processing are discovered in a timely manner. When the average line width is less than or equal to the second preset average line width and greater than the first preset average line width, the average side-etching angle of each point is detected, and the average side-etching angle deviation is calculated. When the average side-etching angle deviation is greater than the preset side-etching angle deviation, the side-etching angle deviation is large. In this case, due to reasons such as uneven distribution of the etching solution, the side-etching degree is uneven during the etching process. At this time, the processing parameters of the circuit board need to be further adjusted. When the average side-etching angle deviation is less than or equal to the preset side-etching angle deviation, the circuit board is determined to be qualified at this time. By detecting the side-etching angle deviation, the processing accuracy and quality of the circuit board are improved. When the average line width is greater than the second preset average line width, the average line width is large. At this time, it is caused by excessive circuit doubling compensation during the circuit design process. At this time, the determination standard is adjusted to more accurately adapt to the design of different circuit line widths, so as to more precisely evaluate the quality of the circuit board. The determination standard is made more flexible and accurate, and the quality control accuracy of the circuit board product is improved. Further, the preparation efficiency of the circuit board is improved.

[0017] Further, when the average deviation amount is greater than the second preset average deviation amount, the average deviation is large, and the circuit board is determined to be unqualified. Each point is detected in detail, and the proportion of the number of abnormal points is calculated. When the proportion of abnormal points is less than or equal to the preset proportion of abnormal points, the proportion is small. At this time, the abnormal situation is local. Due to the unreasonable setting of the ventilation holes, the flow of the chemical solution is blocked, affecting the electroplating quality, thereby causing a deviation in the circuit size. The number of ventilation holes is increased, and the increased number of ventilation holes is determined based on the average distribution distance. By increasing the number of ventilation holes, the flow of the chemical solution is improved, the electroplating quality is improved, and the circuit size deviation is reduced. When the abnormal point distribution parameter is greater than the second preset distribution value, the proportion is large. At this time, further analysis is carried out in combination with the types of abnormal points. Targeted analysis and improvement are carried out according to the types of abnormal points. When the number of abnormal circuits is greater than or equal to the number of abnormal drill holes, the proportion of circuits is large. At this time, the circuit doubling compensation is readjusted to improve the problems existing in the circuit processing process. When the number of abnormal circuits is less than the number of abnormal drill holes, the proportion of drill holes is large. At this time, the drilling process is optimized, and the laser scanning speed during the laser drilling process is adjusted to the corresponding value to reduce the drilling roughness. The processing accuracy and quality of the circuit board are improved, and the preparation efficiency of the circuit board is further improved.

[0018] Furthermore, the processing accuracy and product yield of the millimeter-wave radar circuit board are improved. During the actual production process, the processing technology and judgment criteria are adjusted in a timely manner according to the detection results to ensure that the performance of the circuit board meets the requirements of the millimeter-wave radar, providing strong support for the reliable operation of the L4-level autonomous driving system. Description of the Drawings

[0019] Figure 1 It is a flowchart of the steps of the high-precision processing method for the millimeter-wave radar circuit board according to the embodiment of the present invention; Figure 2 It is a logical decision diagram for determining whether the processing of the circuit board is qualified based on the average deviation amount according to the embodiment of the present invention. Detailed Embodiments

[0020] In order to make the objectives and advantages of the present invention clearer, the present invention will be further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0021] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and do not limit the protection scope of the present invention.

[0022] Please refer to Figure 1 and Figure 2 as shown, which are respectively a flowchart of the steps of the high-precision processing method for the millimeter-wave radar circuit board according to the embodiment of the present invention and a logical decision diagram for determining whether the processing of the circuit board is qualified based on the average deviation amount; a high-precision processing method for a millimeter-wave radar circuit board according to an embodiment of the present invention includes: S1, determining the substrate and the radio frequency circuit; S2, determining line multiplication compensation, transferring and etching the radio frequency circuit; S3, laser drilling; S4, hole filling electroplating; S5, surface protection treatment to obtain the completed circuit board; S6, determining the average deviation amount based on the image information of the obtained completed circuit board; S7, determining whether the processing of the circuit board is qualified based on the average deviation amount, including: Determining that the processing of the circuit board is abnormal, identifying the abnormal points in each preset detection point, and adjusting the processing parameters of the circuit board based on the proportion of the abnormal points, including adjusting the line multiplication compensation to the corresponding value, adjusting the laser scanning speed during the laser drilling process to the corresponding value, or adjusting the number of ventilation holes during the laser drilling process to the corresponding value; Alternatively, if it is determined that the processing of the circuit board is qualified, continue to use the current processing parameters to complete the processing of each circuit board.

[0023] Specifically, in the above-mentioned S1, the substrate material should be a hydrocarbon material substrate with low loss and high dielectric constant stability. It is required that the flatness error of the substrate surface is controlled within ±5μm, and the thickness uniformity error is controlled within ±10μm.

[0024] Specifically, in the above-mentioned S1, for the design of the RF circuit, professional circuit design software can be used in combination with electromagnetic simulation software for design and optimization. The electromagnetic characteristics of the circuit are predicted through electromagnetic simulation, the circuit layout is optimized, and signal interference and loss are reduced, including determining the line spacing and impedance matching.

[0025] Specifically, there is no limitation on the specific method for determining the line multiplication compensation in the above-mentioned S2. Preset line multiplication compensation can be set according to different line widths and spacings. For lines with a width less than 50μm, the compensation value is 3 - 5μm; for lines with a width between 50 - 100μm, the compensation value is 5 - 8μm; for lines with a width greater than 100μm, the compensation value is 8 - 12μm, which will not be elaborated here.

[0026] Specifically, there is no limitation on the specific method for etching the RF circuit in the above-mentioned S2. An acidic copper chloride etching solution with a concentration controlled at 120 - 140g / L and a temperature controlled at 45 - 50°C can be used for etching. The etching time is determined according to the line thickness and design requirements, which will not be elaborated here.

[0027] Specifically, the pads and copper-free areas adopt a right-angle design, with the right-angle error controlled within ±1° and the dimension error controlled within ±3μm. The right-angle design can avoid the etching water flow effect and ensure the signal transmission quality.

[0028] Specifically, the laser drilling in the above-mentioned S3 includes composite laser segmented drilling: for the hydrocarbon material layer, first use a carbon dioxide laser for rough drilling, with the carbon dioxide laser power set at 20 - 30W, the pulse frequency at 20 - 30kHz, and the drilling depth reaching about 80% of the total depth; then use a UV laser for fine drilling, with the UV laser power set at 5 - 10W and the pulse frequency at 50 - 100kHz to complete the remaining drilling. The composite laser segmented drilling process combines the advantages of fast drilling speed of the carbon dioxide laser and high drilling accuracy of the UV laser, and can effectively improve the drilling quality.

[0029] Specifically, during the filling and electroplating in the above-mentioned S4, ventilation holes are evenly arranged on the electroplating frame. The setting of the ventilation holes is to solve the problem of the electroplating frame hiding the potion and improve the electroplating quality.

[0030] Specifically, in the step S5, the surface protection treatment includes treating the pads with the ENIG+OSP composite process to improve the solderability and corrosion resistance of the pads. A wide protective trace loop is provided at the edge of the circuit board, which is a prior art and will not be elaborated here.

[0031] Specifically, the process of determining the average deviation amount based on the obtained image information of the completed circuit board preparation includes: Performing image detection on the processed circuit board to obtain image information, and obtaining the actual line widths of the lines at each preset detection point; Calculating the absolute value of the difference between each actual line width and the corresponding preset line width to obtain the deviation value at the corresponding preset detection point; Solving the average value of each deviation value to obtain the average deviation amount.

[0032] Specifically, the process of determining whether the processing of the circuit board is qualified based on the average deviation amount includes: If the average deviation amount is less than or equal to the first preset average deviation amount, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continuously used to complete the processing of each circuit board; If the average deviation amount is less than or equal to the second preset average deviation amount and greater than the first preset average deviation amount, it is determined whether the processing of the circuit board is qualified in combination with the average line width; If the average deviation amount is greater than the second preset average deviation amount, it is determined that the processing of the circuit board is abnormal, the abnormal points in each preset detection point are identified, and the processing parameters of the circuit board are adjusted based on the abnormal point ratio.

[0033] Specifically, the first preset average deviation amount P1 is selected within the range of [3μm, 5μm], and the second preset average deviation amount P2 is selected within the range of [8μm, 10μm].

[0034] Specifically, the setting method of the preset detection points is not limited. They can be evenly distributed on each line of the circuit board, or evenly distributed in the line dense area and around the pads of the circuit board, which will not be elaborated here.

[0035] Specifically, the specific method for obtaining the actual line widths of the lines at each preset monitoring point is not limited. The image information can be obtained through a high-precision image detection device, and edge detection and analysis are performed on the image information to determine the actual line widths of the lines at each point.

[0036] Specifically, determining whether the processing of the circuit board is qualified in combination with the average line width includes: Solving the average value of the actual line widths of the lines at each preset detection point to obtain the average line width; If the average line width is less than or equal to the first preset average line width, it is determined that the processing of the circuit board is abnormal, the abnormal points in each preset detection point are identified, and the processing parameters of the circuit board are adjusted based on the proportion of abnormal points; If the average line width is less than or equal to the second preset average line width and greater than the first preset average line width, it is determined whether the processing of the circuit board is qualified based on the average etching angle deviation; If the average line width is greater than the second preset average line width, the first preset average deviation amount is adjusted to the corresponding value based on the line width difference amount.

[0037] Specifically, the first preset average line width K1 is selected within the range of [2μm, 3μm], and the second preset average line width K2 is selected within the range of [7μm, 8μm].

[0038] Specifically, the process of determining whether the processing of the circuit board is qualified based on the average etching angle deviation includes: Obtain the actual angles between the sides and the bottom surfaces of the lines at each preset detection point; Calculate the difference between each actual angle and the corresponding preset side etching angle to obtain the etching angle difference; Solve the average value of the etching angle differences at each preset detection point to obtain the average etching angle deviation; If the average etching angle deviation is less than or equal to the preset etching angle deviation, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continuously used to complete the processing of each circuit board; If the average etching angle deviation is greater than the preset etching angle deviation, it is determined that the processing of the circuit board is abnormal, the abnormal points in each preset detection point are identified, and the processing parameters of the circuit board are adjusted based on the proportion of abnormal points.

[0039] Specifically, the preset etching angle deviation is selected within the range of [1°, 2°].

[0040] Specifically, there is no limitation on the method for determining the actual angles at each preset detection point. The scanning electron microscope (SEM) can be used to scan the surface of the circuit board with an electron beam, collect secondary electron signals to form an image, and the ImageJ image processing software can be used to analyze the image. In the software, the angle measurement tool can be used to automatically calculate the angle size by selecting the pixel points corresponding to the two sides of the angle to determine the actual angle, or the coordinate measuring instrument can be used to accurately measure the coordinate position of the object in three-dimensional space and accurately measure the characteristic points on the circuit board to calculate the actual angle. This is the prior art and will not be elaborated here.

[0041] Specifically, it is determined whether the processing of the circuit board is qualified based on the average deviation amount. The average deviation amount characterizes the error condition of the circuit board. When the average deviation amount is less than or equal to the first preset average deviation amount, the circuit processing accuracy is high, the deviation is within the acceptable range, and the performance requirements of the millimeter-wave radar are met. This ensures the quality and performance stability of the circuit board. When the average deviation amount is less than or equal to the second preset average deviation amount and greater than the first preset average deviation amount, further determination is made in combination with the average line width. When the average line width is less than or equal to the first preset average line width, the average line width is too small, which will affect the resistance and signal transmission ability of the circuit, resulting in a decline in the performance of the circuit board. In this case, it is determined that the processing of the circuit board is abnormal, and problems in circuit processing are discovered in a timely manner. When the average line width is less than or equal to the second preset average line width and greater than the first preset average line width, the average side-etch angle of each point is detected, and the average value of the side-etch angle deviation is calculated. When the average etch angle deviation is greater than the preset etch angle deviation, the etch angle deviation is large. In this case, due to reasons such as uneven distribution of the etching solution, the side-etch degree is uneven during the etching process. At this time, the processing parameters of the circuit board need to be further adjusted. When the average etch angle deviation is less than or equal to the preset etch angle deviation, it is determined that the circuit board is qualified at this time. By detecting the etch angle deviation, the processing accuracy and quality of the circuit board are improved. When the average line width is greater than the second preset average line width, the average line width is large. At this time, it is caused by excessive line doubling compensation during the circuit design process. At this time, the judgment standard is adjusted to more accurately adapt to the design of different circuit line widths, so as to more precisely evaluate the quality of the circuit board. The judgment standard is made more flexible and accurate, and the quality control accuracy of the circuit board product is improved. The preparation efficiency of the circuit board is further improved.

[0042] Specifically, the first preset average deviation amount is adjusted to a corresponding value based on the line width difference amount, where the difference between the average line width and the second preset average line width is recorded as the line width difference amount; the increase amplitude of the first preset average deviation amount is proportional to the line width difference amount.

[0043] In this embodiment, optionally, the line width difference amount is compared with the first preset line width difference amount and the second preset line width difference amount; if the line width difference amount is less than or equal to the first preset line width difference amount, the first preset average deviation amount is adjusted to 1.11 times the initial first preset average deviation amount; if the line width difference amount is less than or equal to the second preset line width difference amount and greater than the first preset line width difference amount, the first preset average deviation amount is adjusted to 1.18 times the initial first preset average deviation amount; if the line width difference amount is greater than the second preset line width difference amount, the first preset average deviation amount is adjusted to 1.23 times the initial first preset average deviation amount; The first preset line width difference is taken as 0.3K2, and the second preset line width difference is taken as 0.7K2.

[0044] Specifically, the process of identifying abnormal points in each preset detection point includes: Comparing the deviation value of each preset detection point with the first preset average deviation one by one; Marking the preset detection points with deviation values greater than the first preset average deviation as abnormal points; The process of adjusting the processing parameters of the circuit board based on the proportion of abnormal points includes: Calculating the ratio of the number of statistically abnormal points to the total number of each preset detection point to obtain the proportion of abnormal points; If the proportion of abnormal points is less than or equal to the preset proportion of abnormal points, the number of ventilation holes in the electroplating frame during the S4 hole filling electroplating process is adjusted to the corresponding value based on the abnormal point distribution parameter; If the proportion of abnormal points is greater than the preset proportion of abnormal points, the processing parameters of the circuit board are adjusted based on the proportion of the types of abnormal points.

[0045] The preset proportion of abnormal points is selected within the interval [0.19, 0.25].

[0046] Specifically, adjusting the number of ventilation holes to the corresponding value based on the abnormal point distribution parameter, where Obtaining the distances between abnormal points, calculating the average value of each distance to obtain the abnormal point distribution parameter; The increase amplitude of the number of ventilation holes is proportional to the abnormal point distribution parameter.

[0047] In this embodiment, optionally, Comparing the abnormal point distribution parameter with the first preset distribution value and the second preset distribution value; If the abnormal point distribution parameter is less than or equal to the first preset distribution value, the number of ventilation holes is increased to 1.1 times the initial number of ventilation holes; If the abnormal point distribution parameter is less than or equal to the second preset distribution value and greater than the first preset distribution value, the number of ventilation holes is increased to 1.2 times the initial number of ventilation holes; If the abnormal point distribution parameter is greater than the second preset distribution value, the number of ventilation holes is increased to 1.3 times the initial number of ventilation holes; The first preset distribution value is taken as 3mm, and the second preset distribution value is taken as 5mm.

[0048] Specifically, adjusting the processing parameters of the circuit board based on the proportion of the types of abnormal points includes: Obtaining the types corresponding to the abnormal points, and the types include lines and drill holes; Respectively, record the number of abnormal points of the type of circuit as the number of abnormal circuits, and record the number of abnormal points of the type of drilling as the number of abnormal drill holes; If the number of abnormal circuits is greater than or equal to the number of abnormal drill holes, adjust the circuit multiplication compensation to the corresponding value based on the number of abnormal circuits; If the number of abnormal circuits is less than the number of abnormal drill holes, adjust the laser scanning speed during the laser drilling process to the corresponding value based on the average difference.

[0049] Specifically, adjust the laser scanning speed during the laser drilling process to the corresponding value based on the average difference, where Solve the difference between the average deviation and the second preset average deviation to obtain the average difference; The reduction amplitude of the laser scanning speed is proportional to the average difference.

[0050] In this embodiment, optionally, Compare the average difference with the first preset average difference and the second preset average difference; If the average difference is less than or equal to the first preset average difference, adjust the laser scanning speed to 0.98 times the initial laser scanning speed; If the average difference is less than or equal to the second preset average difference and greater than the first preset average difference, adjust the laser scanning speed to 0.88 times the initial laser scanning speed; If the average difference is greater than the second preset average difference, adjust the laser scanning speed to 0.78 times the initial laser scanning speed; The first preset average difference is taken as 0.25P2, and the first preset average difference is taken as 0.36P2.

[0051] Specifically, adjust the circuit multiplication compensation to the corresponding value based on the number of abnormal circuits, where The increase amplitude of the circuit multiplication compensation is proportional to the number of abnormal circuits.

[0052] In this embodiment, optionally, Compare the number of abnormal circuits with the first preset abnormal number and the second preset abnormal number; If the number of abnormal circuits is less than or equal to the first preset abnormal number, adjust the circuit multiplication compensation to 1.07 times the initial circuit multiplication compensation; If the number of abnormal circuits is less than or equal to the second preset abnormal number and greater than the first preset abnormal number, adjust the circuit multiplication compensation to 1.13 times the initial circuit multiplication compensation; If the number of abnormal circuits is greater than the second preset abnormal number, adjust the circuit multiplication compensation to 1.22 times the initial circuit multiplication compensation; The first preset abnormal quantity is taken as 0.14N0, and the second preset abnormal quantity is taken as 0.23N0, where N0 is the total number of preset detection points.

[0053] Specifically, when the average deviation quantity is greater than the second preset average deviation quantity, the average deviation is large, and it is determined that the circuit board is unqualified. Each point is inspected in detail, and the proportion of the number of abnormal points is calculated. When the proportion of abnormal points is less than or equal to the preset proportion of abnormal points, the proportion is small. At this time, the abnormal situation is local. Due to the unreasonable setting of the ventilation holes, the chemical solution flow is blocked, affecting the electroplating quality, and thus resulting in circuit size deviation. Increase the number of ventilation holes, and determine the increased number of ventilation holes based on the average distribution distance. By increasing the number of ventilation holes, the chemical solution flow situation is improved, the electroplating quality is enhanced, and the circuit size deviation is reduced. When the abnormal point distribution parameter is greater than the second preset distribution value, the proportion is large. At this time, further analysis is carried out in combination with the types of abnormal points. Targeted analysis and improvement are carried out according to the types of abnormal points. When the number of abnormal circuits is greater than or equal to the number of abnormal drill holes, the circuit proportion is large. At this time, the circuit doubling compensation is readjusted to improve the problems existing in the circuit processing technology. When the number of abnormal circuits is less than the number of abnormal drill holes, the drill hole proportion is large. At this time, the drill hole process is optimized, and the laser scanning speed during the laser drill hole process is adjusted to the corresponding value to reduce the drill hole roughness. The processing accuracy and quality of the circuit board are improved, and the preparation efficiency of the circuit board is further enhanced.

[0054] Specifically, the processing accuracy and product yield of the millimeter-wave radar circuit board are improved. During the actual production process, the processing technology and judgment criteria are adjusted in a timely manner according to the detection results to ensure that the performance of the circuit board meets the requirements of the millimeter-wave radar, providing strong support for the reliable operation of the L4-level autonomous driving system.

[0055] So far, the technical solutions of the present invention have been described in combination with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of the present invention.

[0056] The above are only the preferred embodiments of the present invention and are not used to limit the present invention; for those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-precision processing method for a millimeter-wave radar circuit board, characterized in that, Including: S1, determining a substrate and a radio frequency circuit; S2, determining line multiplication compensation, transferring and etching the radio frequency circuit; S3, laser drilling; S4, via filling electroplating; S5, surface protection treatment to obtain a completed circuit board; S6, determining an average deviation amount based on the image information of the obtained completed circuit board; S7, determining whether the processing of the circuit board is qualified based on the average deviation amount, including: Determining that the processing of the circuit board is abnormal, identifying abnormal points in each preset detection point, and adjusting the processing parameters of the circuit board based on the proportion of abnormal points, including adjusting the line multiplication compensation to a corresponding value, adjusting the laser scanning speed during laser drilling to a corresponding value, or adjusting the number of ventilation holes during laser drilling to a corresponding value; Or, determining that the processing of the circuit board is qualified and continuously using the current processing parameters to complete the processing of each circuit board.

2. The high-precision processing method for a millimeter-wave radar circuit board according to claim 1, wherein The process of determining the average deviation amount based on the image information of the obtained completed circuit board includes: Performing image detection on the processed circuit board to obtain image information and obtaining the actual line width of the line at each preset detection point; Calculating the absolute value of the difference between each actual line width and the corresponding preset line width to obtain the deviation value of the corresponding preset detection point; Solving the average value of each deviation value to obtain the average deviation amount; The process of determining whether the processing of the circuit board is qualified based on the average deviation amount includes: If the average deviation amount is less than or equal to the first preset average deviation amount, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continuously used to complete the processing of each circuit board; If the average deviation amount is less than or equal to the second preset average deviation amount and greater than the first preset average deviation amount, it is determined whether the processing of the circuit board is qualified in combination with the average line width; If the average deviation amount is greater than the second preset average deviation amount, it is determined that the processing of the circuit board is abnormal, identifying abnormal points in each preset detection point, and adjusting the processing parameters of the circuit board based on the proportion of abnormal points.

3. The high-precision processing method of the millimeter-wave radar circuit board according to claim 2, characterized in that, Determining whether the processing of the circuit board is qualified in combination with the average line width includes: Solving the average value of the actual line widths of the lines at each preset detection point to obtain the average line width; If the average line width is less than or equal to the first preset average line width, it is determined that the processing of the circuit board is abnormal, identifying abnormal points in each preset detection point, and adjusting the processing parameters of the circuit board based on the proportion of abnormal points; If the average line width is less than or equal to the second preset average line width and greater than the first preset average line width, it is determined whether the processing of the circuit board is qualified based on the average etching angle deviation; If the average line width is greater than the second preset average line width, the first preset average deviation amount is adjusted to a corresponding value based on the line width difference amount.

4. The high-precision processing method for a millimeter-wave radar circuit board according to claim 3, wherein, The process of determining whether the processing of the circuit board is qualified based on the average etching angle deviation includes: Obtaining the actual angle between the side and the bottom of the line at each preset detection point; Calculating the difference between each actual angle and the corresponding preset side etching angle to obtain the etching angle difference; Solving the average value of the etching angle differences of each preset detection point to obtain the average etching angle deviation; If the average etching angle deviation is less than or equal to the preset etching angle deviation, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continuously used to complete the processing of each circuit board; If the average etching angle deviation is greater than the preset etching angle deviation, it is determined that the processing of the circuit board is abnormal, the abnormal points among the preset detection points are identified, and the processing parameters of the circuit board are adjusted based on the proportion of the abnormal points.

5. The high-precision processing method of the millimeter-wave radar circuit board according to claim 4, wherein Adjust the first preset average deviation amount to the corresponding value based on the line width difference amount, where The difference between the average line width and the second preset average line width is recorded as the line width difference amount; The increase amplitude of the first preset average deviation amount is proportional to the line width difference amount.

6. The high-precision processing method of the millimeter-wave radar circuit board according to claim 5, wherein, The process of identifying the abnormal points among the preset detection points includes: Compare the deviation value of each preset detection point with the first preset average deviation amount one by one; Mark the preset detection points with deviation values greater than the first preset average deviation amount as abnormal points; The process of adjusting the processing parameters of the circuit board based on the proportion of the abnormal points includes: Solve the ratio of the number of statistically abnormal points to the total number of each preset detection point to obtain the proportion of the abnormal points; If the proportion of the abnormal points is less than or equal to the preset proportion of the abnormal points, adjust the number of ventilation holes in the plating frame during the S4 blind via plating process to the corresponding value based on the abnormal point distribution parameter; If the proportion of the abnormal points is greater than the preset proportion of the abnormal points, adjust the processing parameters of the circuit board based on the proportion of the types of the abnormal points.

7. The high-precision processing method of the millimeter-wave radar circuit board according to claim 6, wherein, Adjust the number of ventilation holes to the corresponding value based on the abnormal point distribution parameter, where Obtain the distances between the abnormal points, solve the average value of each distance to obtain the abnormal point distribution parameter; The increase amplitude of the number of ventilation holes is proportional to the abnormal point distribution parameter.

8. The high-precision processing method for a millimeter-wave radar circuit board according to claim 7, wherein Adjusting the processing parameters of the circuit board based on the proportion of the types of the abnormal points includes: Obtain the types corresponding to the abnormal points, and the types include lines and drill holes; Record the number of abnormal points of the type of line as the abnormal line number, and record the number of abnormal points of the type of drill hole as the abnormal drill hole number respectively; If the number of abnormal lines is greater than or equal to the number of abnormal drill holes, adjust the line multiplication compensation to the corresponding value based on the number of abnormal lines; If the number of abnormal lines is less than the number of abnormal drill holes, adjust the laser scanning speed during the laser drilling process to the corresponding value based on the average difference amount.

9. The high-precision processing method of the millimeter-wave radar circuit board according to claim 8, characterized in that, Adjust the laser scanning speed during the laser drilling process to the corresponding value based on the average difference amount, where Solve the difference between the average deviation amount and the second preset average deviation amount to obtain the average difference amount; The decrease amplitude of the laser scanning speed is proportional to the average difference amount.

10. The high-precision processing method for the millimeter-wave radar circuit board according to claim 9, characterized in that, Adjust the line multiplication compensation to the corresponding value based on the number of abnormal lines, where The increase amplitude of the line multiplication compensation is proportional to the number of abnormal lines.

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