A high-precision processing method for millimeter-wave radar circuit boards

Abstract

The present invention relates to the technical field of automotive circuit boards, and in particular to a high-precision processing method for a millimeter-wave radar circuit board. The method comprises the following steps: determining a substrate and a radio frequency circuit; determining circuit multiplication compensation, transferring and etching the radio frequency circuit; laser drilling; hole-filling electroplating; surface protection treatment, and obtaining a completed circuit board; determining an average deviation; and determining whether the processing of the circuit board is qualified based on the average deviation. When it is determined that the processing of the circuit board is abnormal, abnormal points in preset detection points are identified, and processing parameters of the circuit board are adjusted based on the proportion of abnormal points. When it is determined that the processing of the circuit board is abnormal, the processing technology is adjusted in a timely manner according to the circuit condition of the detected circuit board when it is determined that the processing of the circuit board is abnormal, thereby improving the production efficiency of the circuit board.

Description

Technical Field

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

[0002] Self-driving cars, also known as driverless cars or computer-driven cars, rely on computer systems to achieve unmanned driving. These systems require numerous sensors and complex circuits. Millimeter-wave radar, with its long transmission distance and high signal accuracy, outperforms infrared, laser, ultrasonic, and camera sensors, making it the mainstream sensor for autonomous driving. Millimeter-wave radar operates in the 24GHz and 77GHz frequency bands. 77GHz millimeter-wave radar is used for long-range forward detection, while 24GHz millimeter-wave radar is used for short-range rear and lateral detection. Existing 77GHz millimeter-wave radars require circuit boards made of polytetrafluoroethylene glass cloth-clad copper laminates.

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

[0004] Chinese patent application publication number: CN119767559A, discloses a method for processing millimeter-wave radar circuit boards, which uses continuous blind slots to replace the multiple independent blind hole structures in the traditional structure, thereby forming a continuous radio frequency circuit pattern, eliminating the multiple electroplating, single-sided copper reduction and circuit etching processes in the traditional processing method, and can directly realize the production of outer layer circuits, first copper layers and second copper layers through activation and copper deposition. It can be seen that the above technical solution has the following problems: it does not take into account the timely adjustment of the processing technology when the circuit board preparation abnormality is determined based on the circuit condition of the detected circuit board, which affects the preparation efficiency of the circuit board. Summary of the Invention

[0005] To this end, the present invention provides a high-precision processing method for millimeter-wave radar circuit boards, which is used to overcome the problem in the prior art that the processing technology is not adjusted in time according to the circuit conditions of the detected circuit boards when abnormalities in the preparation of the circuit boards are determined, thereby affecting the preparation efficiency of the circuit boards.

[0006] To achieve the above objectives, the present invention provides a high-precision processing method for a millimeter-wave radar circuit board, comprising:

[0007] S1, determine the substrate and RF circuit;

[0008] S2, determining circuit multiplication compensation, transferring and etching the RF circuit;

[0009] S3, laser drilling;

[0010] S4, via-fill plating;

[0011] S5, surface protection treatment, obtaining the prepared circuit board;

[0012] S6, determining an average deviation based on the acquired image information of the prepared circuit board;

[0013] S7, determining whether the processing of the circuit board is qualified based on the average deviation, including:

[0014] Determining processing anomalies of the circuit board, identifying abnormal points among the preset detection points, and adjusting processing parameters of the circuit board based on the proportion of abnormal points, including adjusting the circuit multiplication compensation to a corresponding value, adjusting the laser scanning speed during the laser drilling process to a corresponding value, or adjusting the number of ventilation holes during the laser drilling process to a corresponding value;

[0015] Alternatively, it is determined that the processing of the circuit boards is qualified, and the current processing parameters are continuously used to complete the processing of each circuit board.

[0016] Furthermore, the process of determining the average deviation based on the acquired image information of the prepared circuit board includes:

[0017] Perform image inspection on the processed circuit board to obtain image information and the actual line width at each preset inspection point;

[0018] Calculate the absolute value of the difference between the actual line width and the corresponding preset line width to obtain the deviation value of the corresponding preset detection point;

[0019] Solve the average value of each deviation value to obtain the average deviation;

[0020] The process of determining whether the processing of the circuit board is qualified based on the average deviation includes:

[0021] If the average deviation is less than or equal to the first preset average 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;

[0022] If the average deviation is less than or equal to the second preset average deviation and greater than the first preset average deviation, determining whether the processing of the circuit board is qualified in combination with the average line width;

[0023] If the average deviation is greater than the second preset average 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 the abnormal points.

[0024] Furthermore, the average line width is combined to determine whether the processing of the circuit board is qualified, including:

[0025] Calculate the average value of the actual line width at each preset detection point to obtain the average line width;

[0026] If the average line width is less than or equal to a first preset average line width, determining that processing of the circuit board is abnormal, identifying abnormal points among the preset detection points, and adjusting processing parameters of the circuit board based on the proportion of abnormal points;

[0027] 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, determining whether the processing of the circuit board is qualified based on the average etch angle deviation;

[0028] If the average line width is greater than the second preset average line width, the first preset average deviation is adjusted to a corresponding value based on the line width difference.

[0029] Furthermore, the process of determining whether the processing of the circuit board is qualified based on the average etch angle deviation includes:

[0030] Obtain the actual angle between the side and bottom surfaces of each preset detection point line;

[0031] Calculate the difference between each actual angle and the corresponding preset side erosion angle to obtain the side erosion angle difference;

[0032] Calculate the average value of the eclipse angle difference of each preset detection point to obtain the average eclipse angle deviation;

[0033] If the average etch angle deviation is less than or equal to the preset etch angle deviation, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continued to be used to complete the processing of each circuit board;

[0034] If the average etch angle deviation is greater than the preset etch 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 the abnormal points.

[0035] Furthermore, the first preset average deviation is adjusted to a corresponding value based on the line width difference, wherein:

[0036] Recording the difference between the average line width and the second preset average line width as a line width difference;

[0037] The increase range of the first preset average deviation is proportional to the line width difference.

[0038] Furthermore, the process of identifying abnormal points in each preset detection point includes:

[0039] Comparing the deviation value of each preset detection point with the first preset average deviation value one by one;

[0040] Marking a preset detection point where the deviation value is greater than a first preset average deviation as an abnormal point;

[0041] The process of adjusting the processing parameters of the circuit board based on the proportion of abnormal points includes:

[0042] Calculate the ratio of the number of statistical abnormal points to the total number of preset detection points to obtain the abnormal point ratio;

[0043] If the abnormal point ratio is less than or equal to the preset abnormal point ratio, the number of ventilation holes in the electroplating frame in the S4 hole filling electroplating process is adjusted to a corresponding value based on the abnormal point distribution parameter;

[0044] If the abnormal point ratio is greater than the preset abnormal point ratio, the processing parameters of the circuit board are adjusted based on the type ratio of the abnormal points.

[0045] Furthermore, the number of ventilation holes is adjusted to a corresponding value based on the abnormal point distribution parameter, wherein:

[0046] Obtain the distance between each abnormal point, calculate the average value of each distance, and obtain the abnormal point distribution parameters;

[0047] The increase in the number of ventilation holes is proportional to the distribution parameters of abnormal points.

[0048] Furthermore, the processing parameters of the circuit board are adjusted based on the proportion of the types of abnormal points, including:

[0049] Get the types of abnormal points, including lines and boreholes;

[0050] The number of abnormal points of the type of line is recorded as the number of abnormal lines, and the number of abnormal points of the type of borehole is recorded as the number of abnormal boreholes;

[0051] If the number of abnormal lines is greater than or equal to the number of abnormal boreholes, the line multiplication compensation is adjusted to the corresponding value based on the number of abnormal lines;

[0052] If the number of abnormal lines is less than the number of abnormal drilled holes, the laser scanning speed during the laser drilling process is adjusted to a corresponding value based on the average difference.

[0053] Furthermore, the laser scanning speed during the laser drilling process is adjusted to a corresponding value based on the average difference, wherein,

[0054] Calculating the difference between the average deviation and a second preset average deviation to obtain an average difference;

[0055] The reduction in laser scanning speed is proportional to the amount of the average difference.

[0056] Furthermore, the line multiplication compensation is adjusted to a corresponding value based on the number of abnormal lines, wherein,

[0057] The increase in line multiplication compensation is proportional to the number of abnormal lines.

[0058] Compared with the prior art, the present invention has the beneficial effect of determining whether the processing of a circuit board is qualified based on the average deviation. The average deviation represents the error of the circuit board. When the average deviation is less than or equal to a first preset average deviation, 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 is less than or equal to a second preset average deviation and greater than the first preset average deviation, further determination is made based on 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 affects the resistance and signal transmission capability of the circuit, resulting in a decrease in circuit board performance. In this case, the processing of the circuit board is determined to be abnormal, and problems in the circuit processing are promptly discovered. 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 undercut angle of each point is detected and the average undercut angle deviation is calculated. When the average undercut angle deviation is greater than the preset undercut angle deviation, the undercut angle deviation is large. In this case, due to uneven distribution of the etching solution, the degree of undercut during the etching process is uneven, and further adjustment of the circuit board processing parameters is required. When the average etch angle deviation is less than or equal to the preset etch angle deviation, the circuit board is deemed qualified. By detecting 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, which is caused by excessive line multiplication compensation during the line design process. In this case, the judgment criteria are adjusted to more accurately adapt to designs with different line widths, thereby more accurately assessing the quality of the circuit board. This makes the judgment criteria more flexible and accurate, improving the quality control precision of the circuit board products and further improving the production efficiency of the circuit boards.

[0059] Furthermore, when the average deviation is greater than a second preset average deviation, the average deviation is large, and the circuit board is deemed unqualified. Each point is then inspected in detail, and the percentage of abnormal points is calculated. When the percentage of abnormal points is less than or equal to the preset percentage, the percentage is small, indicating that the abnormality is localized. Improper ventilation hole placement results in poor solution flow, impacting electroplating quality and leading to circuit dimensional deviation. The number of ventilation holes is increased, and the number of additional ventilation holes is determined based on the average distribution distance. By increasing the number of ventilation holes, solution flow is improved, electroplating quality is enhanced, and circuit dimensional deviation is reduced. When the abnormal point distribution parameter is greater than the second preset distribution value, the percentage is large, and further analysis is performed based on the type of abnormal points. Targeted analysis and improvements are performed based on the type of abnormal points. When the number of abnormal lines is greater than or equal to the number of abnormal drill holes, the percentage of lines is high, and the line multiplication compensation is readjusted to improve existing problems in the line processing process. When the number of abnormal lines is less than the number of abnormal drill holes, the percentage of drill holes is high, and the drilling process is optimized by adjusting the laser scanning speed during the laser drilling process to a corresponding value to reduce drill hole roughness. The processing accuracy and quality of the circuit board are improved, and the preparation efficiency of the circuit board is further improved.

[0060] Furthermore, this has improved the processing accuracy and product yield of millimeter-wave radar circuit boards. During actual production, the processing technology and judgment criteria are adjusted promptly based on test results to ensure that the circuit board performance meets the requirements of millimeter-wave radar, providing strong support for the reliable operation of Level 4 autonomous driving systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 This is a flowchart of the steps of the high-precision processing method of the millimeter-wave radar circuit board according to an embodiment of the present invention;

[0062] Figure 2 This is a logic decision diagram for determining whether the processing of a circuit board is qualified based on the average deviation according to an embodiment of the present invention. DETAILED DESCRIPTION

[0063] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0064] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0065] See also Figure 1 as well as Figure 2 As shown in the figure, they are respectively a flowchart of the steps of the high-precision processing method of the millimeter-wave radar circuit board according to an embodiment of the present invention, and a logic determination diagram for determining whether the processing of the circuit board is qualified based on the average deviation; a high-precision processing method of the millimeter-wave radar circuit board according to an embodiment of the present invention includes:

[0066] S1, determine the substrate and RF circuit;

[0067] S2, determining circuit multiplication compensation, transferring and etching the RF circuit;

[0068] S3, laser drilling;

[0069] S4, via-fill plating;

[0070] S5, surface protection treatment, obtaining the prepared circuit board;

[0071] S6, determining an average deviation based on the acquired image information of the prepared circuit board;

[0072] S7, determining whether the processing of the circuit board is qualified based on the average deviation, including:

[0073] Determining processing anomalies of the circuit board, identifying abnormal points among the preset detection points, and adjusting processing parameters of the circuit board based on the proportion of abnormal points, including adjusting the circuit multiplication compensation to a corresponding value, adjusting the laser scanning speed during the laser drilling process to a corresponding value, or adjusting the number of ventilation holes during the laser drilling process to a corresponding value;

[0074] Alternatively, it is determined that the processing of the circuit boards is qualified, and the current processing parameters are continuously used to complete the processing of each circuit board.

[0075] Specifically, in S1, the substrate material should be a hydrocarbon substrate with low loss and high dielectric constant stability. The substrate surface flatness error is required to be controlled within ±5 μm, and the thickness uniformity error is required to be controlled within ±10 μm.

[0076] Specifically, in S1, the RF circuit can be designed and optimized using professional circuit design software combined with electromagnetic simulation software. Electromagnetic simulation can predict the electromagnetic characteristics of the circuit, optimize the circuit layout, reduce signal interference and loss, and determine line spacing and impedance matching.

[0077] Specifically, the specific method for determining the line multiplication compensation in S2 is not limited. A preset line multiplication compensation can be set based on line width and spacing. For line widths less than 50 μm, the compensation value is 3-5 μm; for line widths between 50-100 μm, the compensation value is 5-8 μm; and for line widths greater than 100 μm, the compensation value is 8-12 μm. This will not be further described.

[0078] Specifically, the specific method of etching the RF circuit in S2 is not limited. Etching can be performed using a cupric chloride acid etching solution with a concentration controlled at 120-140 g / L and a temperature controlled at 45-50°C. The etching time is determined according to the circuit thickness and design requirements, which will not be repeated here.

[0079] Specifically, the pads and copper-free areas adopt a right-angle design, with the angle error controlled within ±1° and the dimensional error within ±3μm. The right-angle design can avoid the etching water flow effect and ensure the quality of signal transmission.

[0080] Specifically, the laser drilling process in S3 includes composite laser segmented drilling: For hydrocarbon layers, a CO2 laser is first used for rough drilling, with a power of 20-30W and a pulse frequency of 20-30kHz, to drill approximately 80% of the total depth. A UV laser is then used for fine drilling, with a power of 5-10W and a pulse frequency of 50-100kHz, to complete the remaining holes. This composite laser segmented drilling process combines the advantages of CO2 laser drilling speed and UV laser drilling precision, effectively improving drilling quality.

[0081] Specifically, during the S4 hole-filling electroplating process, ventilation holes are evenly arranged on the electroplating frame. The provision of the ventilation holes solves the problem of chemical accumulation in the electroplating frame and improves the electroplating quality.

[0082] Specifically, in S5, the surface protection treatment includes treating the pads with an ENIG+OSP composite process to improve the solderability and corrosion resistance of the pads. A wide protective routing ring is provided at the edge of the circuit board, which is a prior art and will not be described in detail.

[0083] Specifically, the process of determining the average deviation based on the acquired image information of the prepared circuit board includes:

[0084] Perform image inspection on the processed circuit board to obtain image information and the actual line width at each preset inspection point;

[0085] Calculate the absolute value of the difference between the actual line width and the corresponding preset line width to obtain the deviation value of the corresponding preset detection point;

[0086] Calculate the average value of each deviation value to obtain the average deviation.

[0087] Specifically, the process of determining whether the processing of the circuit board is qualified based on the average deviation includes:

[0088] If the average deviation is less than or equal to the first preset average 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;

[0089] If the average deviation is less than or equal to the second preset average deviation and greater than the first preset average deviation, determining whether the processing of the circuit board is qualified in combination with the average line width;

[0090] If the average deviation is greater than the second preset average 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 the abnormal points.

[0091] Specifically, the first preset average deviation amount P1 is selected within the interval [3 μm, 5 μm], and the second preset average deviation amount P2 is selected within the interval [8 μm, 10 μm].

[0092] Specifically, there is no limitation on the setting method of the preset detection points, which can be evenly distributed on each circuit of the circuit board, or evenly distributed in the circuit-dense area and around the pads of the circuit board, which will not be elaborated here.

[0093] Specifically, there is no limitation on the specific method of obtaining the actual line width of the line at each preset monitoring point. Image information can be obtained through high-precision image detection equipment, and edge detection analysis can be performed on the image information to determine the actual line width of the line at each point.

[0094] Specifically, the average line width is used to determine whether the processing of the circuit board is qualified, including:

[0095] Calculate the average value of the actual line width at each preset detection point to obtain the average line width;

[0096] If the average line width is less than or equal to a first preset average line width, determining that processing of the circuit board is abnormal, identifying abnormal points among the preset detection points, and adjusting processing parameters of the circuit board based on the proportion of abnormal points;

[0097] 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, determining whether the processing of the circuit board is qualified based on the average etch angle deviation;

[0098] If the average line width is greater than the second preset average line width, the first preset average deviation is adjusted to a corresponding value based on the line width difference.

[0099] Specifically, the first preset average line width K1 is selected within the interval [2 μm, 3 μm], and the second preset average line width K2 is selected within the interval [7 μm, 8 μm].

[0100] Specifically, the process of determining whether the processing of the circuit board is qualified based on the average etch angle deviation includes:

[0101] Obtain the actual angle between the side and bottom surfaces of each preset detection point line;

[0102] Calculate the difference between each actual angle and the corresponding preset side erosion angle to obtain the side erosion angle difference;

[0103] Calculate the average value of the eclipse angle difference of each preset detection point to obtain the average eclipse angle deviation;

[0104] If the average etch angle deviation is less than or equal to the preset etch angle deviation, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continued to be used to complete the processing of each circuit board;

[0105] If the average etch angle deviation is greater than the preset etch 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 the abnormal points.

[0106] Specifically, the preset eclipse angle deviation is selected within the interval [1°, 2°].

[0107] Specifically, there is no limitation on the method of determining the actual angle of each preset detection point. A 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 use image processing software ImageJ to analyze the image. In the software, use the angle measurement tool to select the pixel points corresponding to the two sides of the angle. The software automatically calculates the size of the angle to determine the actual angle, or use a three-coordinate measuring instrument to accurately measure the coordinate position of the object in three-dimensional space through a probe, and accurately measure the feature points on the circuit board to calculate the actual angle. This is existing technology and will not be repeated.

[0108] Specifically, the circuit board processing qualification is determined based on the average deviation. The average deviation characterizes the circuit board's error. When the average deviation is less than or equal to a first preset average deviation, 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 is less than or equal to a second preset average deviation and greater than the first preset average deviation, further determination is made based on 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 circuit resistance and signal transmission capability, resulting in reduced circuit board performance. In this case, the circuit board processing is determined to be abnormal, allowing problems in the circuit processing to be 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 undercut angle of each point is measured and the average undercut angle deviation is calculated. When the average undercut angle deviation is greater than the preset undercut angle deviation, the undercut angle deviation is large. In this case, due to uneven distribution of the etching solution, the degree of undercut during the etching process is uneven, and further adjustment of the circuit board processing parameters is required. When the average etch angle deviation is less than or equal to the preset etch angle deviation, the circuit board is deemed qualified. By detecting 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, which is caused by excessive line multiplication compensation during the line design process. In this case, the judgment criteria are adjusted to more accurately adapt to designs with different line widths, thereby more accurately assessing the quality of the circuit board. This makes the judgment criteria more flexible and accurate, improving the quality control precision of the circuit board products and further improving the production efficiency of the circuit boards.

[0109] Specifically, the first preset average deviation is adjusted to a corresponding value based on the line width difference, wherein:

[0110] Recording the difference between the average line width and the second preset average line width as a line width difference;

[0111] The increase range of the first preset average deviation is proportional to the line width difference.

[0112] In this embodiment, optionally,

[0113] Comparing the line width difference with a first preset line width difference and a second preset line width difference;

[0114] If the line width difference is less than or equal to the first preset line width difference, adjusting the first preset average deviation to 1.11 times the initial first preset average deviation;

[0115] If the line width difference is less than or equal to the second preset line width difference and greater than the first preset line width difference, adjusting the first preset average deviation to 1.18 times the initial first preset average deviation;

[0116] If the line width difference is greater than the second preset line width difference, adjusting the first preset average deviation to 1.23 times the initial first preset average deviation;

[0117] The first preset line width difference is 0.3K2, and the second preset line width difference is 0.7K2.

[0118] Specifically, the process of identifying abnormal points in each preset detection point includes:

[0119] Comparing the deviation value of each preset detection point with the first preset average deviation value one by one;

[0120] Marking a preset detection point where the deviation value is greater than a first preset average deviation as an abnormal point;

[0121] The process of adjusting the processing parameters of the circuit board based on the proportion of abnormal points includes:

[0122] Calculate the ratio of the number of statistical abnormal points to the total number of preset detection points to obtain the abnormal point ratio;

[0123] If the abnormal point ratio is less than or equal to the preset abnormal point ratio, the number of ventilation holes in the electroplating frame in the S4 hole filling electroplating process is adjusted to a corresponding value based on the abnormal point distribution parameter;

[0124] If the abnormal point ratio is greater than the preset abnormal point ratio, the processing parameters of the circuit board are adjusted based on the type ratio of the abnormal points.

[0125] The preset abnormal point ratio is selected within the range of [0.19, 0.25].

[0126] Specifically, the number of ventilation holes is adjusted to the corresponding value based on the abnormal point distribution parameter, where:

[0127] Obtain the distance between each abnormal point, calculate the average value of each distance, and obtain the abnormal point distribution parameters;

[0128] The increase in the number of ventilation holes is proportional to the distribution parameters of abnormal points.

[0129] In this embodiment, optionally,

[0130] Comparing the abnormal point distribution parameter with the first preset distribution value and the second preset distribution value;

[0131] 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;

[0132] 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;

[0133] 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;

[0134] The first preset distribution value is 3 mm, and the second preset distribution value is 5 mm.

[0135] Specifically, the processing parameters of the circuit board are adjusted based on the type and proportion of abnormal points, including:

[0136] Get the types of abnormal points, including lines and boreholes;

[0137] The number of abnormal points of the type of line is recorded as the number of abnormal lines, and the number of abnormal points of the type of borehole is recorded as the number of abnormal boreholes;

[0138] If the number of abnormal lines is greater than or equal to the number of abnormal boreholes, the line multiplication compensation is adjusted to the corresponding value based on the number of abnormal lines;

[0139] If the number of abnormal lines is less than the number of abnormal drilled holes, the laser scanning speed during the laser drilling process is adjusted to a corresponding value based on the average difference.

[0140] Specifically, the laser scanning speed during the laser drilling process is adjusted to a corresponding value based on the average difference, wherein,

[0141] Calculating the difference between the average deviation and a second preset average deviation to obtain an average difference;

[0142] The reduction in laser scanning speed is proportional to the amount of the average difference.

[0143] In this embodiment, optionally,

[0144] comparing the average difference with a first preset average difference and a second preset average difference;

[0145] If the average difference is less than or equal to the first preset average difference, adjusting the laser scanning speed to 0.98 times the initial laser scanning speed;

[0146] If the average difference is less than or equal to the second preset average difference and greater than the first preset average difference, adjusting the laser scanning speed to 0.88 times the initial laser scanning speed;

[0147] If the average difference is greater than the second predetermined average difference, adjusting the laser scanning speed to 0.78 times the initial laser scanning speed;

[0148] The first preset average difference is 0.25P2, and the second preset average difference is 0.36P2.

[0149] Specifically, the line multiplication compensation is adjusted to a corresponding value based on the number of abnormal lines, where:

[0150] The increase in line multiplication compensation is proportional to the number of abnormal lines.

[0151] In this embodiment, optionally,

[0152] Comparing the number of abnormal lines with a first preset abnormal number and a second preset abnormal number;

[0153] If the number of abnormal lines is less than or equal to the first preset abnormal number, the line multiplication compensation is adjusted to 1.07 times the initial line multiplication compensation;

[0154] If the number of abnormal lines is less than or equal to the second preset abnormal number and greater than the first preset abnormal number, the line multiplication compensation is adjusted to 1.13 times the initial line multiplication compensation;

[0155] If the number of abnormal lines is greater than the second preset abnormal number, the line multiplication compensation is adjusted to 1.22 times the initial line multiplication compensation;

[0156] The first preset abnormal number is 0.14N0, and the second preset abnormal number is 0.23N0, where N0 is the total number of preset detection points.

[0157] Specifically, when the average deviation is greater than a second preset average deviation, the average deviation is large, and the circuit board is deemed unqualified. Each point is then inspected in detail, and the percentage of abnormal points is calculated. When the percentage of abnormal points is less than or equal to the preset percentage, the percentage is small, indicating that the abnormality is localized. Improper ventilation hole placement results in poor solution flow, impacting electroplating quality and leading to circuit dimensional deviation. The number of ventilation holes is increased, and the number of additional ventilation holes is determined based on the average distribution distance. By increasing the number of ventilation holes, solution flow is improved, electroplating quality is enhanced, and circuit dimensional deviation is reduced. When the abnormal point distribution parameter is greater than the second preset distribution value, the percentage is large, and further analysis is conducted based on the type of abnormal points. Targeted analysis and improvements are conducted based on the type of abnormal points. When the number of abnormal lines is greater than or equal to the number of abnormal drill holes, the percentage of lines is high, and the line multiplication compensation is readjusted to address existing problems in the line processing process. When the number of abnormal lines is less than the number of abnormal drill holes, the percentage of drill holes is high, and the drilling process is optimized by adjusting the laser scanning speed during the laser drilling process to a corresponding value to reduce drill hole roughness. The processing accuracy and quality of the circuit board are improved, and the preparation efficiency of the circuit board is further improved.

[0158] Specifically, the processing accuracy and product yield of millimeter-wave radar circuit boards have been improved. During actual production, the processing technology and judgment criteria are adjusted promptly based on test results to ensure that the circuit board performance meets the requirements of millimeter-wave radar, providing strong support for the reliable operation of Level 4 autonomous driving systems.

[0159] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

[0160] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A high-precision processing method for millimeter-wave radar circuit boards, characterized in that: include: S1, determine the substrate and RF circuit; S2, determining circuit multiplication compensation, transferring and etching the RF circuit; S3, laser drilling; S4, via-fill plating; S5, surface protection treatment, obtaining the prepared circuit board; S6, determining an average deviation based on the acquired image information of the completed circuit board, performing image inspection on the completed circuit board, acquiring image information, and obtaining the actual line width of the line at each preset inspection point; Calculate the absolute value of the difference between the 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; S7, determining whether the processing of the circuit board is qualified based on the average deviation, including: If the average deviation is less than or equal to the first preset average 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 deviation is less than or equal to the second preset average deviation and greater than the first preset average deviation, determining whether the processing of the circuit board is qualified in combination with the average line width; If the average deviation is greater than a second preset average deviation, determining that the circuit board is processed abnormally, identifying abnormal points in each preset detection point, and adjusting processing parameters of the circuit board based on the proportion of abnormal points, including adjusting the circuit multiplication compensation to a corresponding value, adjusting the laser scanning speed in the laser drilling process to a corresponding value, or adjusting the number of ventilation holes in the electroplating process to a corresponding value; Combined with the average line width, determine whether the processing of the circuit board is qualified, including: Calculate the average value of the actual line width at each preset detection point to obtain the average line width; If the average line width is less than or equal to a first preset average line width, determining that processing of the circuit board is abnormal, identifying abnormal points among the preset detection points, and adjusting 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, determining whether the processing of the circuit board is qualified based on the average etch angle deviation; If the average line width is greater than the second preset average line width, the first preset average deviation is adjusted to a corresponding value based on the line width difference.

2. The high-precision processing method for millimeter-wave radar circuit boards according to claim 1, characterized in that: The process of determining whether the processing of the circuit board is qualified based on the average etch angle deviation includes: Obtain the actual angle between the side and bottom surfaces of each preset detection point line; Calculate the difference between each actual angle and the corresponding preset side erosion angle to obtain the side erosion angle difference; Calculate the average value of the eclipse angle difference of each preset detection point to obtain the average eclipse angle deviation; If the average etch angle deviation is less than or equal to the preset etch angle deviation, it is determined that the processing of the circuit board is qualified, and the current processing parameters are continued to be used to complete the processing of each circuit board; If the average etch angle deviation is greater than the preset etch 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 the abnormal points.

3. The high-precision processing method for millimeter-wave radar circuit boards according to claim 2, characterized in that: The first preset average deviation is adjusted to a corresponding value based on the line width difference, wherein: Recording the difference between the average line width and the second preset average line width as a line width difference; The increase range of the first preset average deviation is proportional to the line width difference.

4. The high-precision processing method for millimeter-wave radar circuit boards according to claim 3, characterized in that: The process of identifying abnormal points among the preset detection points includes: Comparing the deviation value of each preset detection point with the first preset average deviation value one by one; Marking a preset detection point where the deviation value is greater than a first preset average deviation as an abnormal point; The process of adjusting the processing parameters of the circuit board based on the proportion of abnormal points includes: Calculate the ratio of the number of statistical abnormal points to the total number of preset detection points to obtain the abnormal point ratio; If the abnormal point ratio is less than or equal to the preset abnormal point ratio, the number of ventilation holes in the electroplating frame in the S4 hole filling electroplating process is adjusted to a corresponding value based on the abnormal point distribution parameter; If the abnormal point ratio is greater than the preset abnormal point ratio, the processing parameters of the circuit board are adjusted based on the type ratio of the abnormal points.

5. The high-precision processing method for millimeter-wave radar circuit boards according to claim 4, characterized in that: The number of ventilation holes is adjusted to the corresponding value based on the abnormal point distribution parameters, where: Obtain the distance between each abnormal point, calculate the average value of each distance, and obtain the abnormal point distribution parameters; The increase in the number of ventilation holes is proportional to the distribution parameters of abnormal points.

6. The high-precision processing method for millimeter-wave radar circuit boards according to claim 5, characterized in that: Adjust the processing parameters of the circuit board based on the type and proportion of abnormal points, including: Get the types of abnormal points, including lines and boreholes; The number of abnormal points of the type of line is recorded as the number of abnormal lines, and the number of abnormal points of the type of borehole is recorded as the number of abnormal boreholes; If the number of abnormal lines is greater than or equal to the number of abnormal boreholes, the line multiplication compensation is adjusted to the corresponding value based on the number of abnormal lines; If the number of abnormal lines is less than the number of abnormal drilled holes, the laser scanning speed during the laser drilling process is adjusted to a corresponding value based on the average difference.

7. The high-precision processing method for millimeter-wave radar circuit boards according to claim 6, characterized in that: The laser scanning speed during the laser drilling process is adjusted to a corresponding value based on the average difference, wherein, Calculating the difference between the average deviation and a second preset average deviation to obtain an average difference; The reduction in laser scanning speed is proportional to the amount of the average difference.

8. The high-precision processing method for millimeter-wave radar circuit boards according to claim 7, characterized in that: The line multiplication compensation is adjusted to the corresponding value based on the number of abnormal lines, where: The increase in line multiplication compensation is proportional to the number of abnormal lines.

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