Circuit board processing method, device, system, and circuit board

Abstract

Disclosed in the present application are a circuit board processing method, a device, a system, and a circuit board. The processing method comprises the following steps: using a scanning apparatus to scan a circuit board so as to acquire circuit board information, and performing processing on the circuit board on the basis of the circuit board information. The processing method specifically further comprises: providing a multilayer substrate, forming a through hole on the multilayer substrate, and performing electroplating on the through hole to obtain a multilayer substrate having a metal through hole; performing patterning processing on the surface of a top-layer substrate on the multilayer substrate having the metal through hole so as to obtain a multilayer substrate having a surface circuit layer; performing CT scanning on the multilayer substrate to determine a back-drilling depth for the metal through hole, and, on the basis of the back-drilling depth, performing drilling from the metal through hole on the top-layer substrate along the depth direction so as to obtain a circuit board. Thus, the length of a stub after processing meets requirements and is not too large or too small, enabling the circuit board to achieve high signal integrity, improving processing quality, and reducing the scrap rate.

Description

Circuit board processing method, device, system and circuit board

[0001] The present application claims priority to Chinese Patent Application No. 202411294846.0, filed on September 14, 2024, entitled "Multilayer Circuit Board and Back Drilling Processing Method Thereof and Back Drilling Device", Chinese Patent Application No. 202411992649.6, filed on December 31, 2024, entitled "Back Drilling Processing Method, Device and System of Circuit Board", Chinese Patent Application No. 202510086788.0, filed on January 20, 2025, entitled "Back Drilling Depth Control Processing System, Method, Device and Circuit Board Drilling System", Chinese Patent Application No. 202510880295.4, filed on June 27, 2025, entitled "Circuit Board Laser Processing Method, Device and Circuit Board", and Chinese Patent Application No. 202510893190.2, filed on June 30, 2025, entitled "Back Drilling Processing Method, Device and Circuit Board", the contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application belongs to the technical field of circuit board processing, and particularly relates to a circuit board processing method, device, system and circuit board. BACKGROUND

[0003] With the application and rapid development of electronic products, high-frequency high-speed PCBs (printed circuit boards) gradually develop towards high-level, high-density and high-signal integrity requirements, and the requirements for micro-hole processing precision of PCBs (printed circuit boards / printed wiring boards) are increasingly stringent, and the control of residual stubs after back drilling processing becomes more stringent. An ideal back drilling process should be able to achieve the goal of near-zero residual stubs to maximize signal integrity and electromagnetic compatibility and meet the needs of high-speed signal transmission.

[0004] In the prior art, since the drill bit used in the back drilling process has a taper, the device cannot accurately control the depth, and due to factors such as the accuracy of mechanical back drilling and the accuracy of medium thickness measurement, it is difficult to control the residual stub length at a low level in actual application. Therefore, there is an urgent need for a circuit board processing method. SUMMARY

[0005] Therefore, it is necessary to solve the problem of low processing precision in the prior art, and the present application provides a circuit board processing method, device, system and circuit board to improve the processing precision of the circuit board.

[0006] To achieve the above object, the technical scheme adopted by the embodiments of the present application is:

[0007] In a first aspect, the embodiments of the present application provide a processing method of a circuit board, comprising the following steps:

[0008] The scanning device is used to scan the circuit board to obtain information of the circuit board, and the circuit board is processed according to the information of the circuit board.

[0009] Optionally, the processing method comprises the following steps:

[0010] The circuit board comprises a multilayer substrate, a via is formed in the multilayer substrate, and the via is subjected to electroplating treatment to obtain a multilayer substrate with a metal via. The scanning device comprises a CT scanning device, the CT scanning device is used to perform CT scanning on the multilayer substrate to determine a back drilling depth of the metal via to be back drilled, the metal via is subjected to back drilling with a preset depth according to the back drilling depth, and the circuit board is obtained.

[0011] Optionally, the method comprises that the scanning device comprises a computer layered imaging device, the computer layered imaging device is used to scan and obtain depth information corresponding to a back drilling position of the circuit board, and the corresponding back drilling position is subjected to back drilling depth control processing according to the depth information.

[0012] Optionally, the scanning device comprises a detection device, and based on the configured detection device and drilling processing device, the method comprises:

[0013] Based on the circuit board with the electroplated hole, the detection device is used to obtain actual position information of each electroplated hole corresponding to a back drilling processing to be performed on the circuit board to determine a hole position deviation value, actual center coordinates of the back drilling processing are determined according to the hole position deviation value, and a back drilling depth of the corresponding electroplated hole is determined. Based on the actual center coordinates and the back drilling depth of each electroplated hole corresponding to the back drilling processing to be performed, the drilling processing device is used to perform back drilling processing on the circuit board.

[0014] Optionally, the method comprises:

[0015] The scanning device comprises a residual stub detection device, based on a preliminary back drilling structure on the circuit board, the residual stub detection device is controlled to scan the preliminary back drilling structure to obtain residual stub position information of a residual stub in the preliminary back drilling structure. Based on the residual stub position information, the laser is controlled to perform subtractive processing on the residual stub in the preliminary back drilling structure.

[0016] Optionally, the method comprises:

[0017] Obtaining measured thickness data, theoretical thickness data and theoretical process parameter values of the to-be-processed circuit board, wherein the measured thickness data is obtained by scanning the to-be-processed circuit board by a scanning device, and the theoretical process parameter values are determined based on the theoretical thickness data. Adjusting the theoretical process parameter values according to the deviation between the measured thickness data and the theoretical thickness data to obtain target process parameter values. Controlling the laser processing device to process the to-be-processed circuit board according to the target process parameter values.

[0018] In a second aspect, the application provides a back-drilling drilling device, which is integrated with an X-RAY detection device, and is used for back-drilling processing of a circuit board according to the processing method of the first aspect or any one of the embodiments thereof.

[0019] In a third aspect, the application provides a back-drilling drilling system of a circuit board, which comprises a computer layered imaging device. The computer layered imaging device is used for scanning and obtaining depth information corresponding to a back-drilling position of the circuit board, so as to perform back-drilling depth control processing on the corresponding back-drilling position according to the depth information.

[0020] In a fourth aspect, the application provides a back-drilling depth control processing device of a circuit board, which is used for scanning and obtaining depth information corresponding to a back-drilling position of the circuit board by using a computer layered imaging device, so as to perform back-drilling depth control processing on the corresponding back-drilling position according to the depth information.

[0021] In a fifth aspect, the application provides a back-drilling processing device of a circuit board, which comprises a detection device and a drilling processing device, wherein:

[0022] The detection device is used for obtaining actual position information of each to-be-back-drilling processed electroplated hole on the circuit board based on the circuit board with the electroplated holes, so as to determine a hole position deviation value; determining actual center coordinates of back-drilling processing and back-drilling depths of the corresponding electroplated holes according to the hole position deviation value;

[0023] The drilling processing device is used for back-drilling processing of the circuit board based on the actual center coordinates and the back-drilling depths of each to-be-back-drilling processed electroplated hole.

[0024] In a sixth aspect, the application provides a back-drilling processing system of a circuit board, which comprises the drilling processing device and the detection device of the fifth aspect;

[0025] The drilling processing device and the detection device are used for cooperative processing to realize the back-drilling processing method of any one of claims 18 to 24.

[0026] In a seventh aspect, the application provides a back-drilling processing device, which comprises:

[0027] The laser processing device is configured to subtractively process the stubs in the preliminary back drilling structure on the circuit board based on stub position information, wherein the stub position information is obtained by scanning the preliminary back drilling structure by the stub detection device.

[0028] In an eighth aspect, the present application provides a circuit board laser processing device, which comprises a laser processing device and a controller, wherein:

[0029] The laser processing device is configured to process the circuit board to be processed. The controller is configured to obtain measured thickness data of the circuit board to be processed, theoretical thickness data, and theoretical process parameter values, wherein the measured thickness data is obtained by scanning the circuit board to be processed by a scanning device, and the theoretical process parameter values are determined based on the theoretical thickness data. The theoretical process parameter values are adjusted according to the deviation between the measured thickness data and the theoretical thickness data to obtain target process parameter values. The laser processing device is controlled to process the circuit board to be processed according to the target process parameter values.

[0030] In a ninth aspect, the present application provides a circuit board prepared by the processing method of the first aspect and any one of the processing methods. BRIEF DESCRIPTION OF DRAWINGS

[0031] FIG. 1 is a flowchart of a processing method of a circuit board according to an embodiment of the present application;

[0032] FIG. 2 is a schematic diagram of a multilayer substrate formed by pressing according to an embodiment of the present application;

[0033] FIG. 3 is a schematic diagram of a multilayer substrate with a via formed according to an embodiment of the present application;

[0034] FIG. 4 is a schematic diagram of a multilayer substrate with a metal via formed by electroplating according to an embodiment of the present application;

[0035] FIG. 5 is a schematic diagram of a multilayer substrate with a scan pattern positioned to a target layer for secondary drilling according to an embodiment of the present application;

[0036] FIG. 6 is a schematic diagram of the vertical distance between the reference layer position and the target layer position of a multilayer substrate according to an embodiment of the present application;

[0037] FIG. 7 is a schematic diagram of a multilayer substrate with the thickness of each layer of the substrate deformed according to an embodiment of the present application;

[0038] FIG. 8 is a schematic diagram of a back drilling device according to an embodiment of the present application;

[0039] FIG. 9 is a schematic diagram of another back drilling device according to an embodiment of the present application;

[0040] FIG. 10 is a partial schematic diagram of a longitudinal cross-sectional view according to an example embodiment of the present application;

[0041] FIG. 11 is a flowchart illustrating a process of determining depth information by a processing module of a computer tomographic imaging apparatus according to an exemplary embodiment of the present application;

[0042] FIG. 12 is a schematic view of a three-dimensional image according to an exemplary embodiment of the present application;

[0043] FIG. 13 is a partial schematic view of a longitudinal sectional view according to another exemplary embodiment of the present application;

[0044] FIG. 14 is a partial schematic view of a two-dimensional tomographic image according to an exemplary embodiment of the present application;

[0045] FIG. 15 is a partial schematic view of a longitudinal sectional view according to another exemplary embodiment of the present application;

[0046] FIG. 16 is a partial schematic view of a two-dimensional tomographic image according to another exemplary embodiment of the present application;

[0047] FIG. 17 is a flowchart illustrating a process of determining a back-drilling controlled depth processing depth by a processing module of a computer tomographic imaging apparatus according to an exemplary embodiment of the present application;

[0048] FIG. 18 is a partial schematic view of a longitudinal sectional view according to another exemplary embodiment of the present application;

[0049] FIG. 19 is a partial schematic view of a longitudinal sectional view according to another exemplary embodiment of the present application;

[0050] FIG. 20 is a schematic block diagram of a back-drilling controlled depth processing system of a circuit board according to an exemplary embodiment of the present application;

[0051] FIG. 21 is a flowchart illustrating a back-drilling controlled depth processing method of a circuit board according to an exemplary embodiment of the present application;

[0052] FIG. 22 is a schematic block diagram of a back-drilling controlled depth processing apparatus of a circuit board according to an exemplary embodiment of the present application;

[0053] FIG. 23 is a schematic block diagram of a circuit board drilling system according to an exemplary embodiment of the present application;

[0054] FIG. 24 is a flowchart illustrating a back-drilling processing method of a circuit board according to an exemplary embodiment of the present application;

[0055] FIG. 25 is a schematic block diagram of a back-drilling processing apparatus of a circuit board according to an exemplary embodiment of the present application;

[0056] FIG. 26 is a flowchart illustrating a back-drilling processing method according to an exemplary embodiment of the present application;

[0057] FIG. 27 is a schematic block diagram of a structure to be processed according to an exemplary embodiment of the present application;

[0058] Fig. 28 is a schematic diagram of a scene of a preliminary back drilling process in an embodiment of the present application;

[0059] Fig. 29 is a schematic diagram of a scene of laser stub reduction in an embodiment of the present application;

[0060] Fig. 30 is a schematic diagram of a structure of a back drilling processing device in an embodiment of the present application;

[0061] Fig. 31 is a schematic diagram of an internal structure of a computer device in an embodiment of the present application;

[0062] Fig. 32 is a schematic diagram of a flow of a circuit board laser processing method in an embodiment of the present application;

[0063] Fig. 33 is a schematic diagram of a flow of a circuit board laser processing method in another embodiment of the present application;

[0064] Fig. 34 is a schematic diagram of a scene before a rotation operation in an embodiment of the present application;

[0065] Fig. 35 is a schematic diagram of a structure of a circuit board laser processing device in an embodiment of the present application.

[0066] Reference signs: 1, copper foil; 2, resin glass fiber; 3, through hole; 4, metal through hole; 5, reference layer; 6, target layer; 7, stub. 300, drilling processing device; 400, detection device. DETAILED DESCRIPTION

[0067] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0068] The terms “first” and “second” and the like in the specification and claims of the present application are used to distinguish different objects, rather than to describe a specific order. In the description of the embodiments of the present application, unless otherwise specified, “a plurality of” means two or more, for example, a plurality of processing units means two or more processing units, and the like; a plurality of elements means two or more elements, and the like.

[0069] It should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate directions or positions based on the directions or positions shown in the drawings, and are used only to facilitate the description of the present application and simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0070] In the embodiments of the present application, the words "exemplarily" or "for example" are used to represent an example, illustration or description. Any embodiment or design scheme described as "exemplarily" or "for example" in the embodiments of the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the words "exemplarily" or "for example" are used to present the relevant concept in a specific manner.

[0071] In an embodiment, the present application provides a processing method of a circuit board, comprising the following steps: scanning the circuit board by using a scanning device to obtain information of the circuit board, and processing the circuit board according to the information of the circuit board.

[0072] The information of the circuit board can include depth information corresponding to a back drilling position of the circuit board, actual position information of an electroplated hole to be back drilled, residual stub position information of a residual stub in a back drilling structure, and measured thickness data of the circuit board. The processing method of the present application will be introduced in the following specific embodiments.

[0073] In an embodiment, the present application provides a processing method of a circuit board, and the flowchart is shown in FIG. 1. The processing method comprises the following steps:

[0074] S101, providing a multilayer substrate, drilling a through hole on the multilayer substrate, and electroplating the through hole to obtain a metal through hole;

[0075] The provided multilayer substrate is shown in FIG. 2. The multilayer substrate is formed by pressing, and each substrate is composed of a copper foil 1 and a resin glass fiber 2. In addition, before pressing the substrates, the circuit pattern has been prepared on the substrates except for the top layer substrate.

[0076] After the multilayer substrate is formed by pressing, a PCB drilling machine is used to machine the board material in FIG. 2 to drill a through hole 3, and a board material as shown in FIG. 3 is obtained. Chemical copper is electroplated in the through hole 3 to obtain a metal through hole 4, as shown in FIG. 4.

[0077] S102, CT scanning the multilayer substrate to determine a back drilling depth of the metal through hole to be back drilled, and back drilling the metal through hole to a preset depth according to the back drilling depth to obtain a circuit board.

[0078] The CT scanning can detect each substrate metal layer of the multi-layer substrate, so that the target layer 6 of the secondary drilling can be positioned according to the scanning graph, as shown in FIG. 5, and the secondary drilling processing is performed from the metal via hole on the top layer substrate according to the back drilling depth H of the target layer 6. In this step, in order to ensure the integrity of signal transmission, the chemical copper between the layers which do not need to be connected by the circuit is removed by depth control drilling on the basis of the primary drilling via hole.

[0079] The processing method of the embodiment adds the CT scanning step of the multi-layer substrate in the original back drilling processing process, so that the back drilling depth of the metal via hole can be determined according to the CT scanning result, the secondary drilling processing is performed from the metal via hole on the top layer substrate according to the depth, so that the residual stub length meets the requirement after the secondary drilling processing according to the back drilling depth, and the residual stub length will not be too large or too small, which ensures that the circuit board achieves high signal integrity, improves the processing quality, and reduces the scrap rate.

[0080] In an embodiment, in the step S102, the CT scanning of the multi-layer substrate includes:

[0081] The region of the multi-layer substrate to be processed back drilling is determined, and the CT scanning of the corresponding position of the multi-layer substrate is performed according to the region of the multi-layer substrate to be processed back drilling.

[0082] In the embodiment, the CT scanning is performed on the specific region of the multi-layer substrate to be processed back drilling, rather than global scanning, and the fast scanning is performed according to the position to be processed, which is used to improve the scanning efficiency and further improve the overall back drilling processing efficiency.

[0083] In an embodiment, in the step S102, the CT scanning of the multi-layer substrate is performed to determine the back drilling depth of the metal via hole to be back drilled, and the back drilling of the metal via hole is performed according to the back drilling depth, including:

[0084] S11, performing graph processing on the top layer substrate surface of the multi-layer substrate having the metal via hole to obtain a multi-layer substrate having a surface circuit layer;

[0085] After obtaining the plurality of metal via holes 4 in FIG. 4, the circuit graph is prepared on the top layer substrate of the multi-layer substrate to obtain the surface circuit layer.

[0086] S12, performing CT scanning on the multi-layer substrate to determine the back drilling depth of the corresponding position of the metal via hole to be back drilled, and performing the back drilling of the metal via hole according to the back drilling depth from the corresponding metal via hole on the top layer substrate along the depth direction.

[0087] Wherein, since the plurality of metal vias are arranged at different positions on the multi-layer substrate, the plurality of metal vias can be back-drilled according to the calculated back-drilling depth respectively.

[0088] In the embodiment, CT scanning is performed on the whole area of the multi-layer substrate to be processed, so that back-drilling of the plurality of metal vias on the top layer substrate can be realized, and the circuit board can achieve higher signal integrity, improve processing quality and reduce the scrap rate.

[0089] In an embodiment, the step S102, i.e. the CT scanning of the multi-layer substrate to determine the back-drilling depth of the metal via to be back-drilled, comprises:

[0090] S201, CT scanning of the multi-layer substrate to determine the reference layer position and the target layer position of the multi-layer substrate, the reference layer position being the depth information of the top layer substrate, and the target layer position being the depth information of the target layer substrate in the multi-layer substrate which does not need to be connected by a circuit;

[0091] S202, calculating the vertical distance between the reference layer position and the target layer position to obtain the back-drilling depth of the metal via from the top layer substrate to the target layer substrate.

[0092] Wherein, a PCB special CT scanning device can be used, and the copper foil of the uppermost layer substrate is used as the reference layer 5, and CT scanning is performed on the board before back-drilling to obtain the actual depth H (back-drilling depth) of the target layer of the board to be back-drilled, that is, the vertical distance between the target layer 6 and the reference layer 5, as shown in FIG. 6.

[0093] The processing method of the embodiment accurately positions the back-drilling depth between the reference layer and the target layer of the multi-layer substrate through CT scanning, and back-drilling can be performed using the back-drilling depth, which can meet the processing requirements, make the length of the stub 7 meet the requirements, improve the processing quality, and reduce the scrap rate of the board.

[0094] In an embodiment, considering that in the processing of back-drilling, in addition to the device accuracy which can cause the length of the stub to be larger or smaller, the thickness variation of the processed board itself also plays a crucial role. Since the resin of the substrate has fluidity, as the number of laminated layers of the multi-layer substrate increases, the thickness of different positions of the same board changes, and if the same back-drilling depth is used for depth control back-drilling, it is also more likely to cause the length of the stub to be larger or smaller or even to be drilled through.

[0095] Therefore, the step S201, i.e. the CT scanning of the multi-layer substrate to determine the reference layer position and the target layer position of the multi-layer substrate, specifically comprises:

[0096] S301, at least three reference points are taken on the upper surface of the top layer substrate of the multi-layer substrate, a reference surface is determined according to the reference points, the depth of the reference surface is calculated, and the reference layer position is obtained;

[0097] Wherein, as shown in Figure 7, the multi-layer substrate with varying thickness of each plate can take three highest points on the surface copper foil of the top layer substrate as reference points, and then calculate the reference surface according to the coordinates of the three reference points, and take the depth of the reference surface as the reference layer position.

[0098] In this step, the reference surface determined by selecting three highest points as reference points is to consider that the circuit board will be covered with a metal aluminum sheet with high flatness on the surface of the top layer substrate in actual processing, and the plane where the metal aluminum sheet is located is simulated through the reference surface as the reference surface of secondary drilling.

[0099] S302, CT scanning is performed on the multi-layer substrate to generate three-dimensional position information of the target layer substrate of the multi-layer substrate, and the depth information of N metal holes on the target layer substrate is extracted from the three-dimensional position information as N target layer positions, N≥1;

[0100] Wherein, after CT scanning of the multi-layer substrate, three-dimensional position information of each layer substrate of the multi-layer substrate can be generated, and the three-dimensional position information of each point on the surface of each layer substrate includes horizontal coordinate, vertical coordinate and vertical coordinate. The vertical coordinates of N metal holes on the surface of the target layer substrate can be extracted to obtain the depth information of the metal holes, that is, N target layer positions. That is, as shown in Figure 7, since the thickness of the target layer substrate also changes, the depth information of the N metal holes obtained is different, that is, different target layer positions.

[0101] In the above step S202, that is, the vertical distance between the reference layer position and the target layer position is calculated to obtain the back drilling depth of the metal through hole from the top layer substrate to the target layer substrate, which specifically includes:

[0102] S303, the vertical distance between the reference layer position and each target layer position is calculated, and N back drilling depths of the metal through hole from the top layer substrate to the target layer substrate are obtained.

[0103] For example, as shown in FIG. 7, the depth information at two metal holes, i.e., the first target layer position OP1 and the second target layer position OP2, is determined, the first target layer position OP1 is subtracted from the reference layer position to obtain the first back drilling depth H1 from the top layer substrate to the target layer substrate in the first metal via; the second target layer position OP2 is subtracted from the reference layer position to obtain the second back drilling depth H2 from the top layer substrate to the target layer substrate in the second metal via. According to FIG. 7, the first back drilling depth H1 is greater than the second back drilling depth H2, then drilling is performed in the first metal via according to the first back drilling depth H1, and drilling is performed in the second metal via according to the second back drilling depth H2.

[0104] The processing method of the embodiment solves the problem that the residual stub length value of the back drilling hole is too long, too short or even drilled through due to the influence of the thickness change of the plate, realizes accurate processing of the back drilling hole, thereby reducing the scrap probability caused by the back drilling hole, and the quality of the product is guaranteed.

[0105] In an embodiment, after the CT scanning of the multi-layer substrate to determine the back drilling depth of the metal via, the processing method further comprises:

[0106] S401, a two-dimensional code containing the back drilling depth is marked at the corner position of the multi-layer substrate;

[0107] S402, the two-dimensional code provided at the corner position of the multi-layer substrate is scanned by a drilling machine, and the back drilling depth is obtained by scanning, so that the drilling machine performs the drilling process according to the back drilling depth.

[0108] The obtained back drilling depth information can be transmitted to the drilling machine in a certain way, for example, a two-dimensional code containing the back drilling depth is provided, and the two-dimensional code is provided at the corner position of the multi-layer substrate which is convenient for the drilling machine to scan.

[0109] The processing method of the embodiment uses CT scanning technology to detect the multi-layer substrate before back drilling hole processing to generate back drilling depth data containing the metal via, and then the mechanical drilling machine reads the back drilling depth data in the two-dimensional code by scanning, and performs back drilling processing according to the back drilling depth, thereby obtaining high-quality back drilling holes.

[0110] In an embodiment, the step S401 of marking the two-dimensional code containing the back drilling depth at the corner position of the multi-layer substrate comprises:

[0111] Exposing and developing a pattern metal of the two-dimensional code at the corner position of the multilayer substrate to facilitate the drilling machine to scan the two-dimensional code to obtain the depth information.

[0112] Exposing and developing a pattern metal of the two-dimensional code at the corner position of the multilayer substrate to facilitate the drilling machine to scan the two-dimensional code to obtain the depth information.

[0113] In an embodiment, the step S401 of marking the two-dimensional code containing the back drilling depth at the corner position of the multilayer substrate includes:

[0114] Spraying a two-dimensional code at the corner position of the multilayer substrate by using a CT scanner to facilitate the drilling machine to scan the two-dimensional code to obtain the depth information.

[0115] Spraying a two-dimensional code at the corner position of the multilayer substrate by using a CT scanner to facilitate the drilling machine to scan the two-dimensional code to obtain the depth information.

[0116] In an embodiment, the step S401 of marking the two-dimensional code containing the back drilling depth at the corner position of the multilayer substrate includes:

[0117] Marking at the corner position of the multilayer substrate by using a laser marking device to form a two-dimensional code at the corner position of the multilayer substrate.

[0118] In an embodiment, the step S401 of marking the two-dimensional code containing the back drilling depth at the corner position of the multilayer substrate includes:

[0119] In an embodiment, after the back drilling depth is obtained by drilling from the metal via hole on the top layer substrate in the depth direction, the method further includes:

[0120] Obtaining reference drilling data of the drilling, comparing the reference drilling data with actual drilling data obtained by detection to obtain a deviation value between the reference drilling data and the actual drilling data, and performing drilling compensation processing on the metal via hole causing the deviation value by using a drilling machine according to the deviation value.

[0121] In this embodiment, the back drilling is performed according to the accurately detected back drilling depth in the secondary drilling, but the detection accuracy does not mean the processing accuracy. In order to improve the processing accuracy, the data of the back drilling hole after processing is further compared with the data of the actual drilling control. When the comparison result deviates, the deviation value is compensated to the drilling machine to realize continuous feedback and improvement of the drilling to improve the processing accuracy.

[0122] In an embodiment, after the drilling process is performed from the metal via on the top layer substrate along the depth direction according to the back drilling depth, the method further comprises:

[0123] The reference drilling data corresponding to the drilling process of the N multi-layer substrates in the current batch is obtained, N > 1, and the N sets of reference drilling data and the detected actual drilling data are compared to obtain the deviation values between the N sets of reference drilling data and the detected actual drilling data. The comprehensive deviation value is determined according to the N deviation values, and the drilling compensation process is performed on the metal via of the multi-layer substrate of the current batch of drilling machines according to the comprehensive deviation value.

[0124] In the back drilling process of each batch of circuit boards, one of the reference drilling data corresponding to the drilling process of the multi-layer substrate or the reference drilling data corresponding to the drilling process of the multi-layer substrate can be used. When multiple reference drilling data is obtained, multiple actual drilling data can be detected, and then the deviation values between the multiple reference drilling data and the actual drilling data can be obtained by calculating the difference. The average value of the multiple deviation values can be obtained, and the comprehensive deviation value can be obtained. According to the comprehensive deviation value, the drilling compensation process is performed on the metal via of each circuit board in the current batch, which can improve the processing precision and consider the drilling efficiency.

[0125] In actual application scenarios, due to uncontrollable factors such as pressing and other processes of different production batches or different specifications of circuit boards, the inner layers of circuit boards in each batch are different. In order to further improve the back drilling precision of each batch of circuit boards, a plurality of first processing data of each batch of circuit boards can be further obtained in advance, the back drilling quality is pre-drilled and CT scanned, and the data of the corresponding circuit board and the processing quality is obtained. Then, when processing different batches of circuit boards, the compensation data of the corresponding batch of circuit boards is obtained, and the processing of the drilling machine is compensated accordingly, so as to improve the corresponding data compensation of different circuit boards and improve the flexibility and applicability of the actual processing scene.

[0126] In an embodiment, the back drilling depth can be obtained by using the transmission mode of network communication of the drilling machine in step S103.

[0127] The depth information can be obtained by the drilling machine through wireless or wired network communication transmission mode, without the need to set a two-dimensional code at the corner position of the multi-layer substrate, so that the depth information can be quickly obtained to speed up the drilling process of the circuit board.

[0128] In an embodiment, the top substrate surface on the multi-layer substrate with the metal through hole is subjected to a graphic processing to obtain a multi-layer substrate with a surface circuit layer, comprising:

[0129] The top substrate surface on the multi-layer substrate is cleaned, a dry film is pasted on the top substrate surface, and the top substrate is subjected to an exposure processing using an exposure device and ultraviolet light; the top substrate is subjected to a development processing to obtain a top substrate with a graphic transfer;

[0130] The top substrate is subjected to a graphic electroplating processing, and the dry film is removed to obtain a multi-layer substrate with a surface circuit layer.

[0131] In an embodiment, the graphic electroplating processing is to electroplate a copper layer with a required thickness and a gold-nickel or tin layer with a required thickness on the exposed copper skin or the hole wall of the circuit pattern, and after the processing, the dry film is removed by using a NaOH solution to expose the non-circuit copper layer, thereby obtaining a multi-layer substrate with a surface circuit layer.

[0132] In an embodiment, the present application provides a circuit board prepared by the processing method as described in any one of the preceding embodiments.

[0133] The circuit board of the present embodiment is processed by a special processing method, so that the length of the stub on the circuit board meets the requirements, the product yield is improved, and the product quality is high.

[0134] In an embodiment, the present application provides a back-drilling drilling device, as shown in FIG. 8, which is integrated with an X-RAY detection device, and is used for drilling processing of a circuit board according to the processing method as described in any one of the preceding embodiments.

[0135] The X-RAY detection device is used for CT scanning of the multi-layer substrate to determine the back-drilling depth of the metal through hole, and the drill of the back-drilling drilling device is used for one-time drilling and secondary drilling processing of the multi-layer substrate, wherein the one-time drilling refers to forming a plurality of metal through holes on the multi-layer substrate, and the secondary drilling refers to drilling processing along the depth direction at part of the metal through holes on the top substrate according to the obtained back-drilling depth.

[0136] In an embodiment, as shown in FIG. 9, the back-drilling drilling device further comprises a controller, a data input end of the controller is connected to a data output end of the X-RAY detection device to obtain CT scanning data, and a data output end of the controller is connected to a data input end of the drill to output the back-drilling depth.

[0137] The controller is used to acquire CT scan data transmitted by the X-RAY inspection device and execute the processes in steps S201 to S202 or steps S301 to S303 above. It calculates N back-drilling depths from the top substrate to the target substrate in some metal through holes and sends the back-drilling depth data to the drilling machine so that the drilling machine can perform secondary drilling on each metal through hole according to the N back-drilling depths.

[0138] In one embodiment, this application provides a back-drilling depth control processing system for circuit boards, which may include a computer layer imaging device.

[0139] Computer-aided layer imaging equipment is used to scan and acquire the depth information corresponding to the back-drilling position of the circuit board, so as to perform back-drilling depth control processing on the corresponding back-drilling position according to the depth information.

[0140] For example, the computer-aided lattice imaging device can be a micron-focus X-ray source device capable of implementing computed lattice imaging (CL) technology. For ease of description, this embodiment will simply refer to it as micro-focus CL. It should be noted that this is merely an exemplary description of a computer-aided lattice imaging device and is not a limitation thereof.

[0141] Micro-focus CL is also a type of micro-focus CT in a broad sense. Therefore, the micro-focus CL in this application can also be classified as micro-focus CT. However, in order to distinguish it from traditional cone-beam scanning CT, this application uses the name "micro-focus CL" to refer to a micron-focus X-ray source device that uses CL imaging technology.

[0142] With the advancement of technology, future industrial cone-beam CT may also achieve high-resolution imaging of large-size PCBs. Therefore, the computer-aided tomography device described in this application is not limited to micro-focus CL devices. It should be understood that the use of micro-nano CL, micro-focus CT, micro-nano CT or planar CT are all within the scope of protection of this application.

[0143] When scanning a PCB board, the micro-focus CL uses an X-ray source to irradiate the PCB board with X-rays and uses a detector to collect two-dimensional projection data. Since materials of different densities within the PCB board absorb and scatter X-rays to different degrees, the projection data received by the detector can characterize the structural information of different locations and layers inside the PCB.

[0144] MicroFocus CL can obtain the depth information corresponding to the back drill position of the circuit board based on the projection data obtained after scanning.

[0145] Therefore, computer layer imaging equipment can be used to obtain the depth information of the back drilling position of the circuit board before the back drilling process, and back drilling depth control processing can be performed on the corresponding back drilling position according to the depth information to control the back drilling depth.

[0146] The computer layered imaging device can also be used to obtain the depth information of the back drilling position of the circuit board after the back drilling process, and the residual stub length of the corresponding back drilling position is detected according to the depth information to determine whether the back drilling depth control process is qualified.

[0147] It should be noted that, when the back drilling is not performed on the circuit board, the back drilling position described in the embodiment can be understood as a to-be-drilled position that needs to be drilled; and when the back drilling has been performed on the circuit board, the back drilling position described in the embodiment can be understood as a position that has been drilled.

[0148] In summary, the back drilling depth control processing system for the circuit board provided in the application uses a computer layered imaging device to scan the circuit board and obtain the depth information corresponding to the back drilling position of the circuit board, and the corresponding back drilling position can be processed according to the depth information during the back drilling process. The computer layered imaging device can obtain the internal density distribution of an object according to the attenuation of X-rays to the object, and the emission and reception of X-rays are not easily disturbed by external noise signals. The application uses the computer layered imaging device to scan the circuit board, which can effectively avoid the influence of external noise signals on the process of obtaining the distribution information of the copper layer in the circuit board, thereby improving the accuracy of the obtained depth information, so that the accuracy of the back drilling depth control process based on the depth information can be further improved.

[0149] In an embodiment, the computer layered imaging device can include a control system and a processing module. The control system of the computer layered imaging device is used to control the computer layered imaging device to scan the circuit board to obtain two-dimensional tomographic images of each layer inside the circuit board.

[0150] The processing module of the computer layered imaging device is used to construct a three-dimensional image of the circuit board according to the two-dimensional tomographic images, and obtain the depth information corresponding to the back drilling position of the circuit board according to the three-dimensional image and the two-dimensional tomographic images of the circuit board. The depth information can include but is not limited to the coordinates of the target structure under the back drilling position of the circuit board in the depth direction of the circuit board.

[0151] For example, when the micro-focus CL scans the PCB, the ray source is used to irradiate the PCB with X-rays, and the detector is used to collect two-dimensional projection data, i.e., the cross-sectional image of a single layer inside the PCB, which is expressed as a two-dimensional tomographic image in the application.

[0152] The control module can obtain a sufficient number of two-dimensional tomographic images of different depths by repeatedly scanning the circuit board multiple times.

[0153] Based on the obtained two-dimensional tomographic images, a three-dimensional image of the PCB is reconstructed. For example, the three-dimensional image reconstruction can be implemented based on a volume rendering method, or a surface rendering method, or based on machine learning, etc. The application does not limit the reconstruction method of the three-dimensional image.

[0154] When the micro-focus CL scans the PCB, the resolution of the obtained image can be changed by adjusting the distance between the ray source of the micro-focus CL and the PCB. For example, when the ray source of the micro-focus CL is very close to the PCB, a larger magnification ratio can be obtained to realize high-resolution imaging, so that the position distribution information of different structures such as the internal conductive layer of the PCB can be more clearly represented in the obtained image.

[0155] After the three-dimensional image of the circuit board is reconstructed, the depth information corresponding to each back-drilling position of the circuit board can be obtained based on the three-dimensional structure represented in the three-dimensional image and the more clear structural characteristics of each layer represented in the two-dimensional tomographic image.

[0156] The depth information can include the coordinates of one or more target structures at the back-drilling position of the circuit board in the depth direction of the circuit board. The target structure can be any conductive layer, insulating layer, or any local structure (such as the end of the stub) that needs to obtain the depth, etc. The present embodiment is not limited. The stub can be understood as the residual stub (such as residual hole copper) in the via after back-drilling, or can be understood as the back-drilling hole STUB.

[0157] For example, the depth information can include: the coordinates of the upper surface of the first conductive layer corresponding to the back-drilling position in the depth direction of the circuit board when the back-drilling is not implemented, that is, the depth value of the upper surface of the first conductive layer; or the coordinates of the end of the stub corresponding to the back-drilling position in the depth direction of the circuit board after the back-drilling is implemented, etc.

[0158] The embodiment scans the circuit board by using a computer layered imaging device to obtain two-dimensional tomographic images of each layer of the circuit board, and then constructs a three-dimensional image of the circuit board according to the obtained two-dimensional tomographic images. Finally, according to the three-dimensional image of the whole circuit board and the two-dimensional tomographic images of different depths, the depth information corresponding to the back drilling position of the circuit board is obtained, which can include the coordinates of any target structure in the depth direction of the circuit board, such as the coordinates of each conductive layer (such as a copper layer) under the back drilling position in the depth direction. The application uses two-dimensional tomographic images to represent the information on a certain layer (or a certain depth plane) inside the circuit board, and then uses these two-dimensional tomographic images to construct a three-dimensional solid image corresponding to the actual structure of the circuit board. Finally, the coordinates of any target structure under the back drilling position in the depth direction are analyzed by combining the three-dimensional solid image and the two-dimensional image of a single layer. The application clearly obtains the position distribution information of each copper layer inside the PCB through high-resolution imaging, thereby improving the accuracy of the depth information obtained based on these images, so as to further improve the accuracy when implementing back drilling depth control processing and stub detection based on these coordinates.

[0159] Preferably, the scanning process of the micro-focus CL on the PCB can be implemented between the via drilling process and the back drilling process of the PCB. For example, after the via drilling and plating process of the PCB is completed, the micro-focus CL is used to scan the PCB.

[0160] When the obtained projection data is not complete, the image reconstructed by the CL imaging technology will have interlayer aliasing artifacts. In addition, because the thickness of the conductive layer (such as the copper layer) is very thin, the attenuation degree of the ray passing through the conductive layer and the insulating layer (such as the resin layer) is relatively close. These factors cause the reconstructed three-dimensional image to have the problem that the boundary between the copper layer and the resin is not obvious, and it is difficult to clearly separate the copper layer.

[0161] In view of these problems, the application considers that the attenuation degree of the ray passing through the air and passing through the object is quite different, which causes the copper layer close to the hole wall to be more clearly displayed in the image, specifically, the copper layer close to the hole wall can be displayed as a bright point in the image, as shown in FIG. 10. In this way, the micro-focus CL scanning of the circuit board after the via drilling and plating process is completed can more clearly obtain the position distribution information of each conductive layer in the circuit board.

[0162] Further, the micro-focus CL can realize the off-line reconstruction of the three-dimensional image. That is, after the micro-focus CL scans a PCB, it can directly scan the next PCB, and the reconstruction of the three-dimensional image can be completed at any idle time before the back drilling process starts. For example, after the first drilling process of the PCB is completed, the micro-focus CL scans the PCB, and during the copper plating process of the PCB, the micro-focus CL can complete the reconstruction of the three-dimensional image of the PCB off-line. In this way, when a large number of PCBs need to be back drilled and controlled in depth, the micro-focus CL can complete the reconstruction of the three-dimensional image of the PCB at night or other idle time after completing the scanning of the large number of PCBs, so as to improve the utilization rate of the micro-focus CL equipment and improve the production efficiency.

[0163] In an embodiment, as shown in FIG. 11, the processing module of the computer layered imaging device in the above embodiment acquires the depth information corresponding to the back drilling position of the circuit board according to the three-dimensional image and the two-dimensional tomographic image, and this process can include the following steps:

[0164] S1101, the three-dimensional image of the circuit board is cut along the depth direction of the circuit board to obtain a longitudinal sectional view of the back drilling position of the circuit board.

[0165] For example, FIG. 12 is a three-dimensional image of a circuit board obtained after the micro-focus CL completes the reconstruction of the three-dimensional image. For convenience of description, a coordinate system as shown in FIG. 12 is set, in which the Z axis represents the depth direction of the circuit board, and the X axis and the Y axis represent two directions perpendicular to the depth direction. The surface surrounded by the No. 1 white dotted line is a cross section perpendicular to the Y axis direction, and the sectional view corresponding to the cross section is FIG. 13 (a front view sectional view of the circuit board); the surface surrounded by the No. 2 black dotted line is a cross section perpendicular to the Z axis, and the sectional view corresponding to the cross section is FIG. 14 (a two-dimensional tomographic image of the circuit board, which can also be understood as a top view sectional view of the circuit board); and the surface surrounded by the No. 3 gray dotted line is a cross section perpendicular to the X axis, and the sectional view corresponding to the cross section is FIG. 15 (a left view sectional view of the circuit board).

[0166] The computer layered imaging device can cut the three-dimensional image of the circuit board along the Z axis direction at the back drilling position to obtain FIG. 13 or FIG. 15, and both FIG. 13 and FIG. 15 can be used as a longitudinal sectional view of a back drilling position.

[0167] It is worth noting that the setting of the coordinate system and the description of the sectional views in different directions are only exemplary and not limiting.

[0168] S1102, according to the longitudinal sectional view of the back drilling position and the two-dimensional tomographic image of the circuit board at different depths, a target two-dimensional tomographic image corresponding to the position of the target structure is determined.

[0169] Exemplarily, the top view direction sectional view shown in FIG. 14 can be directly acquired by the detector of the computer layer imaging device; different layer corresponding top view direction sectional views of the circuit board can be acquired through multiple scans, i.e., two-dimensional tomographic images of different depths are obtained.

[0170] The processing module of the computer layer imaging device performs 3D reconstruction based on the acquired two-dimensional tomographic images, obtains a three-dimensional image of the circuit board, and then performs sectioning on the three-dimensional image along the depth direction of the circuit board at the back drilling position to obtain a longitudinal sectional view of the back drilling position.

[0171] The longitudinal sectional view of the back drilling position shows the layering structure at different depths under the back drilling position. For example, for a multi-layer circuit board in which copper layers are conductive layers and resin layers are insulating layers, a partial sectional view of the left view direction before the copper plating process is shown in FIG. 1, and each copper layer under the back drilling position can be determined from the sectional view.

[0172] Since the densities of the copper layers and the resin material in the PCB are different, the two-dimensional tomographic images and the reconstructed three-dimensional image obtained after the micro-focus CL scans the PCB show different gray values for different materials. Therefore, the longitudinal sectional view of the back drilling position and the two-dimensional tomographic images of different depths can be processed by an image segmentation algorithm, and the copper layers and the resin images can be automatically segmented from the images. Then, by comparing the image segmentation results of the longitudinal sectional view and the two-dimensional tomographic images, the segmentation positions of any copper layer and other layers can be determined. In this way, the positions of different structures in the depth direction of the circuit board can be located in the three-dimensional image; for a target structure whose coordinates in the depth direction are needed, the two-dimensional tomographic image corresponding to the position of the target structure can be extracted as the target two-dimensional tomographic image.

[0173] S1103, taking the coordinates of the target two-dimensional tomographic image in the depth direction of the circuit board as the coordinates of the target structure in the depth direction of the circuit board.

[0174] Exemplarily, each two-dimensional tomographic image in the three-dimensional image corresponds to a Z-axis coordinate on the Z-axis. The Z-axis coordinate corresponding to the target two-dimensional tomographic image is taken as the coordinates of the target structure in the depth direction of the circuit board.

[0175] For example, in the scenario where the length of the residual stub needs to be detected after the back drilling process, the end of the residual stub under the back drilling position can be taken as the target structure, and the coordinates of the target structure in the depth direction of the circuit board can be determined by the following method:

[0176] The back-drilled circuit board is scanned to obtain a two-dimensional tomographic image, and a three-dimensional image of the circuit board is constructed based on the two-dimensional tomographic image, as shown in FIG. 12. The three-dimensional image is cut along the depth direction to obtain a longitudinal sectional view shown in FIG. 15. In combination with the longitudinal sectional view shown in FIG. 15 and the two-dimensional tomographic images at different depths, the position of the end of the stub is determined, as indicated by the horizontal dashed line in FIG. 15. The two-dimensional tomographic image corresponding to the position is extracted, that is, the two-dimensional tomographic image shown in FIG. 14. The coordinate of the two-dimensional tomographic image shown in FIG. 14 on the Z axis is the Z axis coordinate of the section framed by the No. 2 black dashed line in the three-dimensional image coordinate system. For example, if the coordinate of the two-dimensional tomographic image on the Z axis is -746.22 μm, then the coordinate of the end of the stub in the depth direction of the circuit board is -746.22 μm.

[0177] For another example, when the coordinate of the upper surface of a target layer in the depth direction of the circuit board needs to be obtained, the following method can be used, where the target layer refers to the conductive layer closest to the back-drilling termination position:

[0178] The target layer is segmented from the longitudinal sectional view of the back-drilling position, and then a two-dimensional tomographic image in which the circuit pattern of the target layer copper layer is clearly displayed is selected from a plurality of two-dimensional tomographic images near the target layer position (the number of the two-dimensional tomographic images can be set according to the gap between the layers of the circuit board and / or the thickness of the target layer, which is not limited in the present application). The two-dimensional tomographic image is determined as the two-dimensional tomographic image corresponding to the upper surface of the target layer, and the corresponding Z axis coordinate of the two-dimensional tomographic image on the Z axis can be used as the coordinate of the upper surface of the target layer in the depth direction of the circuit board.

[0179] Since the two-dimensional tomographic image is directly received by the micro-focus CL detector, it has fewer artifacts than the longitudinal sectional view obtained after image reconstruction and image segmentation, and the plane information represented by the two-dimensional tomographic image is more accurate. As shown in the partial schematic view of a two-dimensional tomographic image in FIG. 16, the resin structure, the circuit pattern of the copper layer, and the copper-plated hole wall can be clearly represented in the two-dimensional tomographic image.

[0180] In the embodiments of the present application, the approximate position of a target structure in a longitudinal sectional view is determined, and then the two-dimensional tomographic image corresponding to the target structure is further positioned by using the two-dimensional tomographic image related to the position. The Z axis coordinate of the target two-dimensional tomographic image in the three-dimensional image coordinate system is used as the coordinate of the target structure in the depth direction of the circuit board. In this way, the influence of artifacts in the reconstructed image on the positioning of the structure segmentation is avoided, so that the target structure is accurately positioned, and the accurate coordinate of the target structure in the depth direction of the circuit board is obtained.

[0181] Preferably, the target structure can include but is not limited to at least one of the following: the upper surface of a single conductive layer and the end of a stub; wherein the upper surface refers to the surface of a conductive layer closest to the back drilling surface of the circuit board. In an example, the back drilling surface can be understood as the back surface of the circuit board.

[0182] In an embodiment, the control system of the computer layered imaging device can further implement the following steps before controlling the computer layered imaging device to scan the circuit board:

[0183] Obtain the back drilling tape file of the circuit board, which can include but is not limited to the back drilling position.

[0184] Correspondingly, the control system controls the computer layered imaging device to scan the circuit board, which can be achieved by the following steps: according to the back drilling position in the back drilling tape file of the circuit board, different areas of the circuit board are scanned with different precision, so that the image precision of the back drilling position in the obtained two-dimensional tomographic image is the highest.

[0185] Illustratively, after the PCB drilling process and before the back drilling process, the micro-focus CL scans the PCB. Before starting the scanning process, the back drilling tape file can be imported into the control system of the micro-focus CL. According to the coordinate information of the back drilling position, the control system of the micro-focus CL automatically performs fine scanning on the area near the back drilling position of the PCB, so that the image of the area near the back drilling position of the PCB in the reconstructed 3D image is clearer, so as to improve the processing precision when calculating the depth information through image segmentation in the subsequent process. The remaining non-back drilling position area of the PCB is scanned coarsely, which can ensure the overall integrity of the 3D image and does not require image precision.

[0186] Through this partition scanning mode, the micro-focus CL scanning time and the 3D image reconstruction time can be saved, and the processing efficiency is improved.

[0187] Further, the back drilling tape file can also include the theoretical depth of the target layer. When the target structure includes the upper surface of the target layer, the control system of the computer layered imaging device determines the target two-dimensional tomographic image corresponding to the position of the target structure according to the longitudinal sectional view of the back drilling position and the two-dimensional tomographic images of different depths of the circuit board. This process can include the following steps:

[0188] According to the theoretical depth of the target layer, determine the area in the longitudinal sectional view that needs to be implemented image segmentation, determine the conductive layer through image segmentation, and take the conductive layer as the target layer; from all the two-dimensional tomographic images related to the target layer, determine the two-dimensional tomographic image that can represent the upper surface of the target layer as the target two-dimensional tomographic image.

[0189] Exemplarily, after obtaining the theoretical depth of the target layer indicated in the back-drilling drill tape file, the processing module of the computer layered imaging device can determine a depth interval centered on the theoretical depth as the region requiring image segmentation, and only needs to perform image segmentation on the region in the longitudinal sectional view, and take one of the segmented conductive layers in the region as the target layer.

[0190] Further, the position of the upper surface of the target layer can be determined first, and then the first two-dimensional tomographic image capable of clearly representing the circuit pattern of the target layer is determined from the two-dimensional tomographic image corresponding to the position and the two-dimensional tomographic images corresponding to other depths adjacent to the position, as the target two-dimensional tomographic image capable of representing the upper surface of the target layer.

[0191] In the embodiment, the micro-focus CL in combination with the theoretical depth of the target layer can further reduce the range of implementing image segmentation, determine the approximate depth range of the target layer, and thus quickly locate the target layer. Or the accuracy of the determined depth information of the target layer can be detected based on the theoretical depth of the target layer.

[0192] In an embodiment, when the target structure includes the upper surface of the target layer and the upper surface of the upper surface layer, the depth information can include the coordinates of the upper surface of the target layer in the depth direction of the circuit board and the coordinates of the upper surface of the upper surface layer in the depth direction of the circuit board; wherein the upper surface layer refers to the first conductive layer drilled in the back-drilling. As shown in FIG. 17, the processing module of the computer layered imaging device can also determine the back-drilling depth of the back-drilling controlled depth processing by implementing the following steps before the back-drilling process:

[0193] S1701, determining the distance between the target layer and the upper surface layer at the back-drilling position according to the depth information.

[0194] Exemplarily, during the back-drilling controlled depth processing, the back-drilling controlled depth processing depth can be determined by the computer layered imaging device.

[0195] First, the processing module of the computer layered imaging device determines the coordinates of the upper surface of the upper surface layer in the depth direction of the circuit board and the coordinates of the upper surface of the target layer in the depth direction of the circuit board according to the three-dimensional image and the two-dimensional tomographic image of the circuit board.

[0196] Then, according to the coordinates of the upper surface of the upper surface layer in the depth direction of the circuit board and the coordinates of the upper surface of the target layer in the depth direction of the circuit board, the distance between the target layer and the upper surface layer at the back-drilling position is determined, such as h1 shown in FIG. 1.

[0197] S1702, determining the back-drilling controlled depth processing depth of the back-drilling position according to the distance.

[0198] Exemplarily, the processing module of the computer layered imaging device determines the back drilling control depth processing depth H of the back drilling position according to the distance h1.

[0199] In the back drilling, the drill bit drills into the circuit board from the back surface until the back drilling depth reaches the back drilling processing depth H.

[0200] In this embodiment, the computer layered imaging device determines the accurate coordinate of the upper surface of the target layer in the depth direction of the circuit board and the accurate coordinate of the upper surface of the upper surface layer, and then calculates the accurate distance between the target layer and the upper surface layer based on the two coordinates, and further determines the back drilling control depth processing depth according to the distance. The back drilling control depth processing depth determined in this way can better meet the actual back drilling requirements of the circuit board, thereby providing protection for subsequent high-precision back drilling processing based on the back drilling control depth processing depth.

[0201] In an embodiment, if the circuit board is scanned after the copper plating process to obtain two-dimensional tomographic images of each layer inside the circuit board, the difference between the distance h1 and the target stub length h can be used as the back drilling control depth processing depth H, that is, H = h1-h.

[0202] For example, the circuit board after the copper plating process is scanned, and a longitudinal sectional view of the back drilling position is cut from the reconstructed three-dimensional image. FIG. 18 is a partial schematic view of a longitudinal sectional view, as shown in FIG. 18, from top to bottom, the first conductive layer is the upper surface layer after copper plating, and the fourth conductive layer is the target layer for back drilling. The computer layered imaging device can determine the distance h1 between the upper surface layer and the target layer based on the reconstructed three-dimensional image and two-dimensional tomographic images at different depths. Since the computer layered imaging device scans the circuit board after the copper plating process, the structural information represented in the two-dimensional tomographic images and the three-dimensional image is the structural information of the circuit board after copper plating. Therefore, the distance h1 determined based on the two-dimensional tomographic images and the three-dimensional image is the actual distance between the upper surface of the upper surface layer and the upper surface of the target layer of the circuit board after copper plating.

[0203] If the micro-focus CL scanning is performed on the PCB after the PCB drilling process, the copper plating thickness after the subsequent copper plating process may not be uniform, which will result in differences in copper plating thickness in different areas of the PCB surface, and finally affect the back drilling control depth accuracy. Therefore, in this embodiment, the micro-focus CL scanning is performed on the PCB after the copper plating process of the PCB, and the accurate distance between the upper surface layer and the target layer of the back drilling position can be obtained.

[0204] The stub length can be understood as the back drilling STUB value. The target stub length is the back drilling STUB target value.

[0205] In an example, a tolerance can be set for the back drilling stub target value h to cope with possible errors in actual back drilling. For example, the back drilling stub target value h can be set as 4±2 mil or 5±3 mil. When calculating the back drilling controlled depth processing depth H of the back drilling position, the basic size 4 mil or 5 mil of the back drilling stub target value h can be substituted into the calculation formula. It should be noted that the back drilling stub target value h is set as 4±2 mil or 5±3 mil in this example, which is only an example and not a limitation of the back drilling stub value.

[0206] In an example, the distance between the surface copper layer and the back drilling target layer at the back drilling position detected by the micro-focus CL device can be controlled within 10 μm. The smaller the detection error, the smaller the back drilling stub target value h can be designed, such as 2±1 mil.

[0207] In an embodiment, if the PCB is scanned after a drilling process and before a copper plating process to obtain two-dimensional tomographic images of each layer inside the PCB, the sum of the distance h1 between the surface layer and the target layer and the copper plating thickness h0 can be calculated first, and then the sum is subtracted by the target stub length h, and the difference obtained is used as the back drilling controlled depth processing depth.

[0208] In an example, if the micro-focus CL scanning process is performed after a drilling process and before a copper plating process of the PCB, the copper plating thickness h0 needs to be considered for compensation. At this time, the back drilling controlled depth processing depth H of the back drilling position can be calculated according to the formula: H=h0+h1-h.

[0209] For example, after the drilling process of the PCB is completed, the PCB is scanned by the micro-focus CL to obtain the accurate distance between the surface copper layer and the back drilling target layer at the back drilling position. As shown in FIG. 1, from top to bottom, the first layer is the surface copper layer, and the fourth layer is the back drilling target layer. After the PCB is scanned by the micro-focus CL, the accurate distance h1 between the first layer surface copper layer and the fourth layer back drilling target layer at the back drilling position can be obtained. According to the back drilling stub target value h and considering the compensation of the copper plating thickness h0, the back drilling controlled depth processing depth H of the back drilling position can be calculated as H=h0+h1-h.

[0210] In this embodiment, the influence of the copper plating thickness after the copper plating process on the back drilling controlled depth accuracy is improved by compensating the copper plating thickness.

[0211] In an embodiment, for a PCB containing a reference layer, the reference layer is located between the top layer and the target layer on the PCB, and by micro-focus CL scanning of the PCB, the accurate distance h2 between the top layer at the back-drilling position and the reference layer, and the accurate distance h3 between the reference layer and the target layer can be obtained. According to the accurate distance h2 between the top layer at the back-drilling position and the reference layer, the accurate distance h3 between the reference layer and the target layer, and the back-drilling STUB target value h, the back-drilling controlled depth processing depth H of the back-drilling position can be calculated.

[0212] In an example, if the micro-focus CL scanning of the PCB is performed after a drilling process of the PCB, the plating copper thickness h0 needs to be compensated. In this case, the back-drilling controlled depth processing depth H of the back-drilling position can be calculated according to the following formula:

[0213] H = h0 + h2 + h3 - h;

[0214] In another example, if the micro-focus CL scanning of the PCB is performed after a plating copper process of the PCB, the plating copper thickness h0 does not need to be compensated. In this case, the back-drilling controlled depth processing depth H of the back-drilling position can be calculated according to the following formula:

[0215] H = h2 + h3 - h;

[0216] Preferably, due to the flowability of the resin in the PP material during the pressing process of the PCB, there is a thickness tolerance after the pressing of the PCB, and the depth positions of the top layer and the inner copper layer in different areas of the PCB are not the same. The copper layer shape is similar to a wave shape, but the degree of the wave is not too large, and within a small limited range, the copper layer depth can be considered to be consistent without fluctuation. Therefore, for the PCB back-drilling processing with low precision requirement, the micro-focus CL does not need to perform fine scanning for each back-drilling position, and can perform fine scanning for only one back-drilling position at the center of a small limited range. Then, the depth information of the back-drilling position is used to represent the depth information of all back-drilling positions in the limited range, and the same back-drilling controlled depth processing depth is set for all back-drilling positions in the limited range, so as to improve the scanning efficiency while ensuring the back-drilling precision.

[0217] Optionally, the limited range is set according to the actual precision, efficiency requirement and performance of the micro-focus CL, and the specific range can be 100mm 2 , 50mm 2 , 25mm 2 , etc., which is not limited in the present application.

[0218] In an embodiment, when the target structure includes the stub end and the upper surface of the target layer, the depth information can include the coordinate of the stub end in the depth direction of the circuit board and the coordinate of the upper surface of the target layer in the depth direction of the circuit board. After the back drilling process, the PCB board can be scanned by the computer layered imaging device, and the length of the stub after back drilling can be detected by the processing module of the computer layered imaging device, which can specifically include the following steps:

[0219] According to the depth information, the length of the stub is calculated; and it is judged whether the length of the stub is within a preset qualified length range, if yes, it is confirmed that the back drilling depth control process is qualified, and if not, it is confirmed that the back drilling depth control process is unqualified.

[0220] Exemplarily, by detecting the depth information of the remaining stub after back drilling through the embodiment, efficient and high-precision detection of the back drilling stub value can be realized.

[0221] For example, the absolute value of the difference between the coordinate of the stub end in the depth direction of the circuit board and the coordinate of the upper surface of the target layer in the depth direction of the circuit board is determined as the length of the stub.

[0222] After the back drilling process is completed, the traditional method often uses the method of slice detection to detect the stub value, which is low in efficiency and can only be spot-checked, and cannot quickly and accurately detect the stub value of the back drilling hole without damaging the PCB board. The nondestructive detection of the PCB board back drilling stub value can realize full-quantity detection of the PCB board quickly.

[0223] As shown in FIG. 19, from top to bottom, the fourth layer is the back drilling target layer. After micro-focal CL scanning of the PCB board, the accurate distance between the back drilling position target layer and the stub end can be obtained based on the obtained image, that is, the back drilling stub value h' shown in FIG. 19.

[0224] In an embodiment, the back drilling depth control processing system can include, in addition to the computer layered imaging device, a circuit board drilling device;

[0225] The control system of the computer layered imaging device is configured to send the back drilling depth control processing depth determined by the processing module to the circuit board drilling device; and the circuit board drilling device is configured to perform back drilling depth control processing at the corresponding back drilling position according to the back drilling depth control processing depth.

[0226] In this embodiment, after the computer layered imaging device acquires the accurate back drilling control depth processing depth, the back drilling control depth processing depth is sent to the circuit board drilling device, so that the circuit board drilling device can perform back drilling at the corresponding back drilling position according to the back drilling control depth processing depth in the back drilling process of the circuit board. In this way, the circuit board drilling device can be provided with high-precision processing depth information in the back drilling control depth processing process, so as to ensure the back drilling control depth precision and quality of the circuit board drilling device.

[0227] Optionally, a main control system can also be arranged in the back drilling control depth processing system of the circuit board, and the main control system is in communication connection with the control system of the computer layered imaging device and the control system of the circuit board drilling device; the control system of the computer layered imaging device is configured to send the back drilling control depth processing depth determined by the processing module to the main control system;

[0228] The main control system is configured to send the back drilling control depth processing depth to the control system of the circuit board drilling device;

[0229] The control system of the circuit board drilling device is configured to perform back drilling control depth processing at the back drilling position according to the back drilling control depth processing depth.

[0230] Exemplarily, FIG. 20 is a structural schematic block diagram of a back drilling control depth processing system of a circuit board according to an example embodiment of the present application. As shown in FIG. 20, the system uses a microfocus CL device as the computer layered imaging device and uses a drilling machine as the circuit board drilling device. In addition to the microfocus CL control system (i.e., the control system of the computer layered imaging device) and the microfocus CL data processing module (i.e., the processing module of the computer layered imaging device), the microfocus CL device can also include a microfocus CL storage module and other modules. The microfocus CL data processing module is connected to the microfocus CL control system, and the microfocus CL storage module is connected to the microfocus CL control system and is configured to store measurement data and calculation data.

[0231] The communication module shown in FIG. 20 is used to realize signal transmission connection between the microfocus CL control system and the control system of the circuit board drilling device (such as the drilling machine control system shown in FIG. 20) in the back drilling control depth processing system of the circuit board.

[0232] The main control system is configured to connect the microfocus CL independent control system and the drilling machine independent control system in series. The microfocus CL data processing module processes the collected projection data to calculate the accurate back drilling control depth processing depth. The main control system transmits the back drilling control depth processing depth of the microfocus CL control system to the drilling machine control system through the communication module, and the drilling machine control system controls the drilling machine to perform back drilling control depth processing.

[0233] Preferably, the back drilling numerical control processing system of the circuit board provided in the above embodiments can be set to share one micro-focus CL by multiple circuit board drilling devices as needed, which is based on the premise that the scanning accuracy and efficiency of the micro-focus CL meet the actual back drilling requirements. In this case, a corresponding identifier, such as a label two-dimensional code / bar code, can be set for each PCB to ensure consistency in data transmission between the micro-focus CL and the drilling control machine. The main control system can transmit the back drilling control depth determined by the micro-focus CL for the PCB from the micro-focus CL control system to the control system of the circuit board drilling device that performs the back drilling processing of the PCB.

[0234] In an embodiment, the present application provides a back drilling control depth processing method for a circuit board, which can include the following steps:

[0235] Scanning and obtaining the depth information corresponding to the back drilling position of the circuit board by using a computer layered imaging device, so as to perform back drilling control depth processing on the corresponding back drilling position according to the depth information.

[0236] It should be noted that the specific implementation of this step can refer to the description of Embodiment One, which will not be repeated here.

[0237] In summary, the present application provides a back drilling control depth processing method for a circuit board, which scans the circuit board by using a computer layered imaging device and obtains the depth information corresponding to the back drilling position of the circuit board. When performing back drilling processing, the corresponding back drilling position can be processed according to the depth information. The computer layered imaging device can obtain the internal density distribution of an object according to the attenuation of X-rays. The emission and reception of X-rays are not easily disturbed by external noise signals. The present application uses a computer layered imaging device to scan the circuit board, which can effectively avoid the influence of external noise signals on the process of obtaining the distribution information of the copper layer in the circuit board, thereby improving the accuracy of the obtained depth information, so as to further improve the accuracy when performing back drilling control depth processing based on the depth information.

[0238] In an embodiment, as shown in FIG. 21, scanning and obtaining the depth information corresponding to the back drilling position of the circuit board by using a computer layered imaging device can include the following steps:

[0239] S2101, scanning the circuit board to obtain two-dimensional tomographic images of each layer inside the circuit board;

[0240] S2102, constructing a three-dimensional image of the circuit board according to the two-dimensional tomographic images;

[0241] S2103, obtaining the depth information corresponding to the back drilling position of the circuit board according to the three-dimensional image and the two-dimensional tomographic images, the depth information including the coordinates of the target structure under the back drilling position of the circuit board in the depth direction.

[0242] It should be noted that the specific implementation method of steps S2101-S2103 can refer to the description of the implementation of the steps of the control system and the processing module of the computer layered imaging device in the above embodiments, which will not be repeated here.

[0243] The embodiment of the present application scans the circuit board by using the computer layered imaging device to obtain two-dimensional tomographic images of each layer inside the circuit board, then constructs a three-dimensional image of the circuit board according to all the obtained two-dimensional tomographic images, and finally obtains depth information corresponding to the back drilling position of the circuit board according to the three-dimensional image of the whole circuit board and the two-dimensional tomographic images of different depths. The depth information can include the coordinates of any target structure in the depth direction of the circuit board, such as the coordinates of each conductive layer (such as copper layer) under the back drilling position in the depth direction. The present application uses two-dimensional tomographic images to represent the information on a certain layer (or a certain depth plane) inside the circuit board, and then uses these two-dimensional tomographic images to construct a three-dimensional solid image corresponding to the actual structure of the circuit board. Finally, the coordinates of any target structure under the back drilling position in the depth direction are analyzed by combining the three-dimensional solid image and the two-dimensional image of a single layer. Through high-resolution imaging, the present application clearly obtains the position distribution information of each copper layer inside the PCB, thereby improving the accuracy of the depth information obtained based on these images, so as to further improve the accuracy when implementing back drilling depth control processing and stub detection based on these coordinates.

[0244] In one embodiment, according to the three-dimensional image and the two-dimensional tomographic image, the depth information corresponding to the back drilling position of the circuit board can include the following steps:

[0245] The three-dimensional image of the circuit board is cut along the depth direction of the circuit board to obtain a longitudinal sectional view of the back drilling position of the circuit board; according to the longitudinal sectional view of the back drilling position and the two-dimensional tomographic images of different depths of the circuit board, a target two-dimensional tomographic image corresponding to the position of the target structure is determined; and the coordinates of the target two-dimensional tomographic image in the depth direction of the circuit board are taken as the coordinates of the target structure in the depth direction of the circuit board.

[0246] In one embodiment, the target structure includes at least one of the following: the upper surface of a single conductive layer and the end of a stub; wherein the upper surface refers to the surface of the conductive layer closest to the drilling surface of the back drilling of the circuit board.

[0247] In one embodiment, before scanning the circuit board, the method further includes: obtaining a back drilling drill tape file of the circuit board, the back drilling drill tape file including a back drilling position; and scanning the circuit board, including: according to the back drilling position in the back drilling drill tape file of the circuit board, implementing different precision scanning on different regions of the circuit board to obtain two-dimensional tomographic images, and the image precision of the back drilling position in the two-dimensional tomographic images is the highest.

[0248] In one of the embodiments, the back-drilling drill tape file further comprises a theoretical depth of the target layer, the target layer being the conductive layer closest to the back-drilling termination position, and the target structure comprising the upper surface of the target layer; the target two-dimensional tomographic image corresponding to the position of the target structure is determined according to the longitudinal sectional view of the back-drilling position and the two-dimensional tomographic images of the circuit board at different depths, comprising: determining the region in the longitudinal sectional view that needs to be implemented image segmentation according to the theoretical depth of the target layer, determining the conductive layer through image segmentation, and taking the conductive layer as the target layer; determining the two-dimensional tomographic image capable of representing the upper surface of the target layer from all the two-dimensional tomographic images related to the target layer as the target two-dimensional tomographic image.

[0249] In one of the embodiments, the target structure comprises the upper surface of the target layer and the upper surface of the upper surface layer, the upper surface layer being the first conductive layer drilled in the back-drilling, and the depth information comprises the coordinates of the upper surface of the target layer in the depth direction of the circuit board and the coordinates of the upper surface of the upper surface layer in the depth direction of the circuit board, and the method further comprises: determining the distance between the target layer and the upper surface layer at the back-drilling position according to the depth information; and determining the back-drilling controlled depth processing depth of the back-drilling position according to the distance.

[0250] In one of the embodiments, the target structure comprises the end of the stub and the upper surface of the target layer; the depth information comprises the coordinates of the end of the stub in the depth direction of the circuit board and the coordinates of the upper surface of the target layer in the depth direction of the circuit board, and the method further comprises: calculating the stub length according to the depth information; and determining whether the stub length is within a preset qualified length range, and if yes, confirming that the back-drilling controlled depth processing is qualified.

[0251] In one of the embodiments, the back-drilling controlled depth processing depth of the back-drilling position is determined according to the distance, comprising: in the case of scanning the circuit board to obtain the two-dimensional tomographic images of each layer inside the circuit board after the copper plating process, taking the difference between the distance and the target stub length as the back-drilling controlled depth processing depth; in the case of scanning the circuit board to obtain the two-dimensional tomographic images of each layer inside the circuit board before the copper plating process, first calculating the sum of the distance and the copper plating thickness, then subtracting the target stub length from the sum, and taking the obtained difference as the back-drilling controlled depth processing depth.

[0252] In one of the embodiments, the step of "scanning and obtaining the depth information corresponding to the back-drilling position of the circuit board" in the above-mentioned embodiment eleven can comprise the following steps: after the through-hole drilling and electroplating processing of the circuit board are completed, scanning and obtaining the depth information corresponding to the back-drilling position of the circuit board.

[0253] In addition, it can also relate to a circuit board back-drilling method, wherein the back-drilling method uses the depth information corresponding to the back-drilling position of the circuit board obtained by the back-drilling controlled depth processing method of any one of the above-mentioned embodiments to perform back-drilling controlled depth processing on the corresponding back-drilling position according to the depth information.

[0254] It should be noted that the specific implementation method of the above embodiment can refer to the description of the control system and the processing module of the computer layered imaging device above, which will not be repeated here.

[0255] In an embodiment, FIG. 22 is a schematic block diagram of a back drilling depth control processing device of a circuit board according to an example embodiment of the present application. The device 2200 includes an information acquisition module 2201.

[0256] The information acquisition module 2201 is configured to scan and acquire depth information corresponding to the back drilling position of the circuit board by using the computer layered imaging device, so as to perform back drilling depth control processing on the corresponding back drilling position according to the depth information.

[0257] In summary, the present application provides a back drilling depth control processing device of a circuit board. The device scans the circuit board by using a computer layered imaging device and acquires depth information corresponding to the back drilling position of the circuit board. The depth information can be used to perform back drilling depth control processing on the corresponding back drilling position. The computer layered imaging device can obtain the internal density distribution of an object according to the attenuation of X-rays. The emission and reception of X-rays are not easily disturbed by external noise signals. The scanning of the circuit board by using the computer layered imaging device can effectively avoid the influence of external noise signals on the acquisition of the distribution information of each copper layer in the circuit board, thereby improving the accuracy of the acquired depth information. The back drilling depth control processing based on the depth information can further improve the accuracy.

[0258] In one embodiment, the information acquisition module includes a control module and a processing module. The control module is configured to scan the circuit board to obtain two-dimensional tomographic images of each layer inside the circuit board. The processing module is configured to construct a three-dimensional image of the circuit board according to the two-dimensional tomographic images, and acquire depth information corresponding to the back drilling position of the circuit board according to the three-dimensional image and the two-dimensional tomographic images. The depth information includes the coordinates of the target structure in the depth direction of the circuit board at the back drilling position.

[0259] In one embodiment, the processing module is configured to: cut the three-dimensional image of the circuit board in the depth direction of the circuit board to obtain a longitudinal sectional view of the back drilling position of the circuit board; determine a target two-dimensional tomographic image corresponding to the position of the target structure according to the longitudinal sectional view of the back drilling position and the two-dimensional tomographic images of different depths of the circuit board; and take the coordinates of the target two-dimensional tomographic image in the depth direction of the circuit board as the coordinates of the target structure in the depth direction of the circuit board.

[0260] In one embodiment, the target structure includes at least one of: the upper surface of a single conductive layer and the end of a stub. The upper surface refers to the surface of the conductive layer closest to the drilling surface of the back drilling of the circuit board.

[0261] In one of the embodiments, before scanning the circuit board, the control module is further configured to: acquire a back drilling drill tape file of the circuit board, the back drilling drill tape file comprising a back drilling position; and scan the circuit board, comprising: performing scanning on different regions of the circuit board with different precisions according to the back drilling position in the back drilling drill tape file of the circuit board to obtain two-dimensional tomographic images, and the image precision of the back drilling position in the two-dimensional tomographic images is the highest.

[0262] In one of the embodiments, the back drilling drill tape file further comprises a theoretical depth of a target layer, the target layer being a conductive layer closest to the back drilling termination position, and the target structure comprising a top surface of the target layer; and the processing module is configured to: determine a region in the longitudinal sectional view that needs to be subjected to image segmentation according to the theoretical depth of the target layer, determine the conductive layer as the target layer through image segmentation, and determine two-dimensional tomographic images capable of representing the top surface of the target layer from all the two-dimensional tomographic images related to the target layer as target two-dimensional tomographic images.

[0263] In one of the embodiments, the target structure comprises the top surface of the target layer and a top surface of an upper layer, the upper layer being the first conductive layer drilled into during back drilling, and the depth information comprises a coordinate of the top surface of the target layer in the depth direction of the circuit board and a coordinate of the top surface of the upper layer in the depth direction of the circuit board; and the processing module is further configured to: determine a distance between the target layer and the upper layer at the back drilling position according to the depth information; and determine the back drilling controlled depth processing depth according to the distance.

[0264] In one of the embodiments, the target structure comprises a residual stub end and a top surface of a target layer; and the depth information comprises a coordinate of the residual stub end in the depth direction of the circuit board and a coordinate of the top surface of the target layer in the depth direction of the circuit board; and the processing module is further configured to: calculate a residual stub length according to the depth information; and determine whether the residual stub length is within a preset qualified length range, and if so, confirm that the back drilling controlled depth processing is qualified.

[0265] In one of the embodiments, the processing module is configured to: in the case of obtaining the two-dimensional tomographic images of the internal layers of the circuit board after the copper plating process, take a difference between the distance and the target residual stub length as the back drilling controlled depth processing depth; and in the case of obtaining the two-dimensional tomographic images of the internal layers of the circuit board before the copper plating process, first calculate a sum of the distance and a copper plating thickness, then subtract the target residual stub length from the sum, and take a difference obtained as the back drilling controlled depth processing depth.

[0266] In one of the embodiments, the information acquisition module is configured to scan and acquire the depth information corresponding to the back drilling position of the circuit board after completing the through hole drilling and electroplating processing of the circuit board.

[0267] In summary, the back drilling depth control processing device of the circuit board provided by the embodiment of the present application uses the computer layered imaging equipment to scan the circuit board to obtain the two-dimensional tomographic images of each layer inside the circuit board, then constructs the three-dimensional image of the circuit board according to the obtained two-dimensional tomographic images, and finally obtains the depth information corresponding to the back drilling position of the circuit board according to the three-dimensional image of the whole circuit board and the two-dimensional tomographic images of different depths. The depth information can include the coordinates of any target structure in the depth direction of the circuit board, such as the coordinates of each conductive layer (such as the copper layer) in the depth direction of the back drilling position. The embodiment uses the two-dimensional tomographic images to represent the information on a certain layer (or a certain depth plane) inside the circuit board, and then uses these two-dimensional tomographic images to construct the three-dimensional solid image corresponding to the actual structure of the circuit board. Finally, the coordinates of any target structure in the depth direction of the back drilling position are analyzed in combination with the three-dimensional solid image and the two-dimensional image of a single layer. The position distribution information of each copper layer inside the PCB is clearly obtained through high-resolution imaging, thereby improving the accuracy of the depth information obtained based on these images, so that the accuracy can be further improved when the back drilling depth control processing and residual stub detection are performed based on these coordinates.

[0268] In an embodiment, FIG. 23 is a schematic block diagram of a circuit board drilling system according to an example embodiment of the present application. The system 2300 can include the back drilling depth control processing device 2200 according to any of the above embodiments.

[0269] It can be understood that the circuit board drilling system according to the embodiment also has the corresponding technical effects based on the corresponding beneficial effects of the above embodiments. To avoid redundancy, the description is not expanded here.

[0270] In an embodiment, the present application provides a circuit board drilling system. The system can include the back drilling depth control processing system according to any of the above embodiments. It can be understood that the circuit board drilling system according to the embodiment also has the corresponding technical effects based on the corresponding beneficial effects of the above embodiments. To avoid redundancy, the description is not expanded here.

[0271] In an embodiment, the present application provides a back drilling processing method for a circuit board. As shown in FIGS. 24 and 25, the detection equipment and the drilling processing equipment are not integrated. The back drilling processing method includes the following steps.

[0272] S2401, based on the circuit board with plated holes, obtaining the actual position information of each corresponding plated hole to be back drilled on the circuit board by the detection equipment to determine the hole position deviation value, determining the actual center coordinates of the back drilling processing according to the hole position deviation value, and determining the back drilling depth of the corresponding plated hole;

[0273] The detection device refers to a detection device independent of the drilling processing device, and can be a hole position detection device.

[0274] In this step, the processing file of the circuit board records the predetermined position of the first drilling, the drilling machine can obtain the processing file in advance, and perform the first drilling on the predetermined position of the PCB according to the processing requirement on the processing file to obtain a through hole. Then, the through hole is subjected to electroplating treatment to obtain a circuit board with an electroplated hole.

[0275] S2402, based on the actual center coordinates and the back drilling depth corresponding to each electroplated hole to be back drilled, the drilling processing device is used to back drill the circuit board.

[0276] It can be understood that the drilling processing device refers to a drilling machine without a detection device for measuring the position information of the electroplated hole. The drilling machine is only used for drilling operation, and is not used for measuring the position of the drilling on the circuit board. However, it should be noted that the drilling processing device can be provided with a detection module for finding the corner target position of the circuit board, such as a CCD camera for target point detection, to realize expansion detection for corresponding compensation, thereby further improving the drilling precision.

[0277] The back drilling processing method of the circuit board in this embodiment can realize the acquisition of the drilling position outside the processing process of the drilling processing device by setting and working independently of the detection device, that is, realizing the pre-detection of the relevant data of the circuit board by a separate detection device. The drilling processing device can be used for back drilling of the circuit board. The position of the electroplated hole on the circuit board is detected by a separate detection device, and the hole position deviation value of the electroplated hole, the actual center coordinates of the back drilling processing, and the back drilling depth corresponding to the electroplated hole are calculated and determined. The cost of data acquisition is low and efficient, and compared with the prior art, the detection device does not need to be integrated beside the main shaft of the drilling processing device, and the relevant data does not need to be temporarily measured by the drilling processing device before drilling. This not only improves the working efficiency of the drilling processing device, but also reduces the complexity and cost of the equipment.

[0278] In an embodiment, the detection device includes a detection device with thickness detection function, and the determination of the back drilling depth corresponding to the electroplated hole specifically includes:

[0279] S2411, measuring the actual thickness of each electroplated hole to be processed on the circuit board by the detection device; and determining the back drilling depth of each electroplated hole to be back drilled according to the actual thickness, the ratio of the target layer design depth to be back drilled to the design thickness of the circuit board.

[0280] In this step, the ratio of the target layer design depth to the design thickness of the circuit board is a fixed value, and the measurement method of the ratio includes:

[0281] The actual plate thickness at the electroplated hole of each back drilling position is measured in the direction of the design thickness of the circuit board, the ratio between the actual plate thickness at the electroplated hole of each back drilling position and the design thickness is calculated, and the ratio of the target layer design depth to the design thickness of the circuit board is obtained.

[0282] The method for determining the back drilling depth of the back drilling to be performed includes: multiplying the design thickness of the electroplated hole at a certain back drilling position of the circuit board by the ratio calculated above to obtain the back drilling depth at the back drilling position.

[0283] S2412, based on the actual center coordinates and the back drilling depth corresponding to each electroplated hole to be back drilled, the back drilling of the circuit board is performed by the drilling processing equipment, specifically including:

[0284] Based on the actual center coordinates corresponding to each electroplated hole to be back drilled, the drilling processing equipment is used to reach each predetermined position, and the back drilling of the circuit board is performed according to the back drilling depth of the corresponding electroplated hole.

[0285] Wherein, the back drilling of the circuit board according to the actual center coordinates and the back drilling depth to be back drilled means that the position is first located, the actual center coordinates are taken as the target point, and the corresponding depth control processing is performed, and the depth of the processing is the back drilling depth.

[0286] The back drilling processing method of the circuit board of the embodiment is characterized in that the detection equipment is set and works separately from the drilling processing equipment, so that the drilling processing equipment can be used for drilling work of the circuit board, the actual position of each electroplated through hole that needs to be back drilled and the deviation of the plate thickness at the through hole are detected by the separate detection equipment; the deviation between the actual position and the theoretical position is corrected and compensated, the back drilling position coordinates of each back drilling hole are corrected during back drilling, so as to improve the actual concentricity between the back drilling hole and the original electroplated through hole during back drilling, and the drilling depth of back drilling is proportionally corrected according to the deviation between the actual plate thickness and the design plate thickness of each hole in position, so as to reduce the deviation between the actual back drilling depth and the actual target position, that is, each hole separately obtains the position deviation compensation value and the depth compensation value. In this way, the drilling position and the plate thickness are obtained outside the drilling processing equipment, the cost of data acquisition and processing is low and efficient, the detection equipment for position detection does not need to be integrated beside the main shaft of the drilling processing equipment, and the related data does not need to be measured before drilling. This not only improves the work efficiency, but also reduces the complexity and cost of the equipment.

[0287] In an embodiment, the detection device comprises a non-destructive detection device, and the non-destructive detection device comprises an X-ray detection device, and the determining the back drilling depth of the corresponding plated hole comprises:

[0288] The back drilling depth of each plated hole to be back drilled is acquired by the non-destructive detection device;

[0289] After the back drilling of the circuit board is completed, the method further comprises:

[0290] The back drilling depth of the corresponding plated hole is detected by the non-destructive detection device to determine whether the back drilling depth is within a target deviation value, and if not, the difference value is fed back to the drilling processing device for compensation adjustment.

[0291] In an embodiment, the back drilling depth of the plated hole is acquired by the X-ray detection device in a CT scanning manner. After the back drilling is completed, the back drilling depth of the corresponding plated hole is detected by the X-ray detection device in a CT scanning manner to determine whether the back drilling depth is within a preset target deviation value. The specific detection and adjustment method comprises: calculating the difference value between the actual back drilling depth and the target back drilling depth, comparing the difference value with the preset target deviation value, and if the difference value is less than or equal to the preset target deviation value, determining that the back drilling depth of the plated hole is within the preset target deviation value; and if the difference value is greater than the preset target deviation value, determining that the back drilling depth of the plated hole is not within the preset target deviation value.

[0292] In an embodiment, the detection device comprises a detection device with thickness detection function and a non-destructive detection device, and before the back drilling of the circuit board is performed by the drilling processing device, the method further comprises:

[0293] S501, the actual thickness of each plated hole to be processed on the circuit board is measured by the detection device, and the first back drilling depth of each plated hole to be back drilled is determined according to the actual thickness of the circuit board, the ratio of the target layer depth to be back drilled to the design thickness of the circuit board, and the thickness of the circuit board.

[0294] In this step, the determination process of the first back drilling depth can refer to the steps in step S2411, and this step will not be described in detail.

[0295] S502, the second back drilling depth of each plated hole to be back drilled is determined by the non-destructive detection device, and it is determined whether the deviation between the first back drilling depth and the second back drilling depth is within a preset deviation range.

[0296] If the deviation between the first back drilling depth and the second back drilling depth is within the preset deviation range, the circuit board is back drilled by the drilling processing device based on the actual center coordinates and according to the first back drilling depth.

[0297] The nondestructive testing device can be a testing device with CT scanning function, and the circuit board is scanned to determine the second back drilling depth of each plated hole to be back drilled. The comparison of whether the deviation between the first back drilling depth and the second back drilling depth is within the preset deviation range can determine whether the first back drilling depth is reliable. For example, when the deviation between the first back drilling depth and the second back drilling depth is within the preset deviation range, it is determined that the determination of the first back drilling depth is reliable, and the circuit board can be back drilled according to the first back drilling depth.

[0298] In an embodiment, the step of obtaining the circuit board with plated holes in step S2401 includes:

[0299] Drilling holes at predetermined positions of the circuit board to obtain through holes penetrating through the circuit board;

[0300] Plating treatment is performed on the through holes to obtain corresponding plated holes on the circuit board.

[0301] The first drilling forms through holes on the circuit board, and the through holes are then plated.

[0302] In an embodiment, the actual position information of each plated hole to be back drilled on the circuit board is obtained by the detection device in step S2401 to determine the hole position deviation value, specifically including:

[0303] S24011, detecting the drilling position of the plated hole on the back drilling surface of the circuit board by using the detection device to obtain the actual position information of the plated hole on the back drilling surface of the circuit board;

[0304] S24012, determining the hole position deviation value according to the actual position information and the theoretical position information of the plated hole on the back drilling surface.

[0305] The drilling position on the circuit board is detected by using the hole position detection device, and the coordinates of the actual position information of the plated hole on the back drilling surface are (x2’, y2’). The coordinates of the theoretical position information of the plated hole on the back drilling surface are (x1, y1). The coordinate difference between the actual position information and the theoretical position information of the plated hole on the back drilling surface is calculated to obtain the hole position deviation value, and the coordinates are (Δx, Δy).

[0306] The back drilling processing method of the embodiment utilizes the cooperation of the detection device and the drilling processing device, applies the pre-acquired plate thickness data and the position data of the to-be-processed hole, realizes efficient alignment (based on coordinate detection and compensation) and compensation depth control processing (proportional mode of back drilling processing) according to the actual plate thickness deviation, so that the actual position of the back drilling hole can be found on the XY axis, and the target layer can be accurately approached in the Z axis direction, thereby improving the precision and efficiency of back drilling processing.

[0307] In an embodiment, the detection device with thickness detection function is a laser thickness measuring device, which is used to measure the actual thickness of the area corresponding to each to-be-back-drilled processing plated hole on the circuit board, so as to improve the accuracy of measurement.

[0308] In an embodiment, the drilling processing device has a plurality of processing spindles. In order to further improve the processing precision, the back drilling processing method comprises:

[0309] The drilling and back drilling processing of the same circuit board are performed on the same processing spindle.

[0310] In this embodiment, considering that there may be certain differences in the processing procedures of each processing spindle, the drilling and back drilling processing of the same circuit board are performed on the same processing spindle, that is, the process traceability control is performed on the circuit board. In practice, the circuit board can be marked or classified for traceability, so that the drilling and back drilling of the same circuit board are completed on the same processing spindle, thereby making the processing precision and consistency of back drilling for each circuit board relatively good.

[0311] In an embodiment, as shown in FIG. 25, the present application provides a back drilling processing device for a circuit board, which comprises:

[0312] a drilling processing device 300 and a detection device 400,

[0313] The detection device is used to acquire the actual position information of each to-be-back-drilled processing corresponding plated hole on the circuit board with plated holes, so as to determine the hole position deviation value; determine the actual center coordinates of back drilling processing according to the hole position deviation value, and determine the back drilling depth of the corresponding plated hole;

[0314] The drilling processing device is used to determine the actual center coordinates of back drilling processing according to the hole position deviation value, and perform back drilling processing on the circuit board.

[0315] It should be noted that in the above process, the hole position deviation value and the back drilling depth corresponding to the actual position information acquired by the detection device can be acquired by the drilling processing device, that is, the following embodiments are performed, which are not limited here:

[0316] Alternatively, the detection device is used to obtain actual position information of each to-be-back-drilling corresponding plated hole on the circuit board based on the circuit board with the plated hole;

[0317] The drilling processing device is used to determine the hole position deviation value, determine the actual center coordinate of the back-drilling processing and the back-drilling depth of the corresponding plated hole according to the hole position deviation value, and perform back-drilling processing on the circuit board according to the actual center coordinate of the back-drilling processing determined according to the hole position deviation value.

[0318] Specifically, the drilling processing device determines the hole position deviation value according to the actual position information and the theoretical position information of the corresponding plated hole of the to-be-back-drilling surface. For brevity, the description of step S24012 is not repeated here.

[0319] The drilling processing device 300 and the detection device 400 are used to work together to realize the back-drilling processing method mentioned in any of the above embodiments. For example, the communication port of the drilling processing device 300 and the communication port of the detection device 400 can communicate with each other. The communication port of the drilling processing device 300 and the communication port of the detection device 400 can be connected by wireless communication or wired connection.

[0320] As another implementation, the communication port of the drilling processing device 300 and the communication port of the detection device 400 can not communicate with each other. After the detection device 400 completes the measurement, the measurement data is obtained by data storage and imported into the drilling processing device 300, and the above back-drilling processing process can also be realized.

[0321] The drilling processing device of the embodiment uses the separately arranged detection device 400 to obtain the plate thickness data and the drilling position data of the to-be-processed hole in advance. The detection data of the same device is used to calculate the hole position deviation and the thickness deviation of each hole that needs to be back-drilled. The hole position deviation and the thickness deviation are directly associated, which can reduce the error caused by measuring the thickness of the plate by external processes, thereby improving the accuracy of the data (the actual center coordinate of the secondary drilling and the back-drilling depth). Compared with the prior art, the processing device of the embodiment does not need to measure the thickness of the plate by external processes to obtain the plate thickness data, which reduces the operation steps and avoids errors caused by external factors.

[0322] In an embodiment, the detection device includes a laser thickness measurement module and / or a hole position detection module, or is a detection device with image sensor function and plate thickness measurement function.

[0323] The hole position detection device is provided with a plane array camera module or an AOI (Auto Optical Inspection) integrated module, the drilling processing device can be provided with a CCD camera to find the target position, detect only several corners of the target position, realize expansion and contraction detection, and compensate. In addition to the processing procedure of the drilling processing device 300 of the circuit board, the independent detection device 400 is arranged to measure the actual hole position deviation and obtain the actual thickness data of the board on which the back drilling processing hole accessory is needed. In this way, the unstable influence caused by the arrangement of the detection device 400 and the drilling processing device 300 together can be avoided, and the efficiency is improved.

[0324] In an embodiment, as shown in FIG. 25, the application provides a back drilling processing system of a circuit board, which comprises:

[0325] a drilling processing device 300;

[0326] a detection device 400;

[0327] The drilling processing device 300 and the detection device 400 are used to work together to realize the back drilling processing method mentioned in any of the above embodiments. The communication ports of the drilling processing device 300 and the detection device 400 can be connected by wireless communication, wired connection or without connection.

[0328] In the process of processing the circuit board, the drilling processing device 300 is used for the first drilling, then the detection device 400 is used for data detection and data calculation of steps S2401 and S2411 to obtain the actual center coordinates of the second drilling and the back drilling depth, and finally the circuit board is fixed on the drilling workbench, and the circuit board is drilled (back drilled) according to the actual center coordinates of the second drilling and the back drilling depth. In other embodiments, the back drilling processing system can also include a drilling workbench for placing the circuit board to be processed.

[0329] The back drilling processing system of the embodiment realizes the acquisition of the drilling position and thickness data on the circuit board outside the processing procedure of the drilling processing device 300, which is low in cost and efficient. The detection device 400 does not need to be integrated beside the main shaft, nor does it need to control the drilling processing device 300 to measure the relevant data before drilling. Instead, the drilling position and thickness data are detected and processed by the separately arranged hole position detection device 400, which not only improves the work efficiency, but also reduces the complexity and cost of the equipment. Compared with the prior art, the application has higher efficiency, higher precision, lower error and lower cost, and has obvious advantages.

[0330] In an embodiment, the detection device 400 is a hole site detection device integrated with a laser thickness measurement module, or a detection device with image sensor function and plate thickness measurement function.

[0331] The embodiment of the present application proposes a back drilling processing method. Compared with the traditional laser thickness measurement technology, the present application scans the actual residual stub in the preliminary back drilling structure after preliminary back drilling processing, which can realize more accurate residual stub positioning. Compared with the traditional mechanical back drilling technology, the laser processing has the characteristics of high precision and non-contact, and can finely subtract the specified position without increasing additional physical stress. In this way, by combining high-precision residual stub positioning and high-precision laser subtracting technology, the traditional mechanical back drilling in precision is broken through, the error caused by inaccurate medium thickness measurement is avoided, the residual stub length can be controlled to a lower level, and the ideal state of zero residual target is closer, so as to significantly improve the signal transmission quality and electromagnetic compatibility performance, and meet the strict requirements of high-speed signal processing on back drilling process.

[0332] In an exemplary embodiment, the present application provides a back drilling processing method, and the embodiment takes the terminal as an example for the execution subject of the method. The terminal can be a back drilling processing device, or other terminals capable of controlling the back drilling processing device, such as various personal computers, notebook computers, smart phones, tablet computers, Internet of Things devices and portable wearable devices, etc. The Internet of Things device can be a smart speaker, a smart television, a smart air conditioner, a smart vehicle device, a projection device, etc. The portable wearable device can be a smart watch, a smart bracelet, a head-mounted device, etc. The head-mounted device can be a virtual reality (VR) device, an augmented reality (AR) device, smart glasses, etc. It can be understood that the execution subject of the method can also be a server, and can also be a system including a terminal and a server, and the implementation is realized through the interaction of the terminal and the server.

[0333] In some feasible embodiments, in the case of laser processing in preliminary back drilling processing, the back drilling processing device is at least integrated with a residual stub detection device and a laser processing device.

[0334] Exemplarily, after the structure to be processed is positioned on the circuit board, the laser processing device can be controlled to perform back drilling processing on the structure to be processed according to the first laser processing parameters to form a preliminary back drilling structure. After the residual stub position information of the residual stub in the preliminary back drilling structure is obtained, the laser processing device can be controlled to perform subtractive processing on the residual stub in the preliminary back drilling structure based on the residual stub position information according to the second laser processing parameters. The processing efficiency of the laser processing device according to the first laser processing parameters is greater than or equal to the processing efficiency of the laser processing device according to the second laser processing parameters. The processing precision of the laser processing device according to the second laser processing parameters is greater than or equal to the processing precision of the laser processing device according to the first laser processing parameters. It can be understood that the higher the laser processing precision is, the lower the processing efficiency is generally. However, with the development of laser processing technology, high-efficiency and high-precision laser processing can be realized at the same time, and the first laser processing parameters can be the same as the second laser processing parameters.

[0335] In other possible implementations, when the preliminary back drilling processing is implemented by using other methods than laser processing, the back drilling processing device at least integrates the preliminary back drilling processing device, the residual stub detection device and the laser processing device. As an example, the other method than laser processing can be mechanical processing.

[0336] Exemplarily, after the structure to be processed is positioned on the circuit board, the laser processing device can be controlled to perform back drilling processing on the structure to be processed according to the first laser processing parameters to form a preliminary back drilling structure. After the residual stub position information of the residual stub in the preliminary back drilling structure is obtained, the laser processing device can be controlled to perform subtractive processing on the residual stub in the preliminary back drilling structure based on the residual stub position information according to the second laser processing parameters. The processing efficiency of the laser processing device according to the first laser processing parameters is greater than or equal to the processing efficiency of the laser processing device according to the second laser processing parameters. The processing precision of the laser processing device according to the second laser processing parameters is greater than or equal to the processing precision of the laser processing device according to the first laser processing parameters. It can be understood that the higher the laser processing precision is, the lower the processing efficiency is generally. However, with the development of laser processing technology, high-efficiency and high-precision laser processing can be realized at the same time, and the first laser processing parameters can be the same as the second laser processing parameters.

[0337] In this embodiment, as shown in FIG. 26, the method includes the following steps S2610-S30. Wherein:

[0338] In step S2610, based on the preliminary back drilling structure on the circuit board, the residual stub detection device is controlled to scan the preliminary back drilling structure to obtain the residual stub position information of the residual stub in the preliminary back drilling structure.

[0339] The circuit board can refer to a board member that needs to be back drilled, including an IC (Integrated Circuit) board or a PCB (Printed Circuit Board) and the like.

[0340] In an exemplary embodiment, the preliminary back-drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back-drilling processing device to perform back-drilling processing on the structure to be processed to form the preliminary back-drilling structure.

[0341] In an exemplary embodiment, the preliminary back-drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back-drilling processing device to perform back-drilling processing on the structure to be processed to form the preliminary back-drilling structure.

[0342] In an exemplary embodiment, the preliminary back-drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back-drilling processing device to perform back-drilling processing on the structure to be processed to form the preliminary back-drilling structure.

[0343] In an exemplary embodiment, the preliminary back-drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back-drilling processing device to perform back-drilling processing on the structure to be processed to form the preliminary back-drilling structure.

[0344] In an exemplary embodiment, the preliminary back-drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back-drilling processing device to perform back-drilling processing on the structure to be processed to form the preliminary back-drilling structure.

[0345] In an exemplary embodiment, the preliminary back-drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back-drilling processing device to perform back-drilling processing on the structure to be processed to form the preliminary back-drilling structure.

[0346] In an exemplary embodiment, the preliminary back-drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back-drilling processing device to perform back-drilling processing on the structure to be processed to form the preliminary back-drilling structure.

[0347] The preliminary back drilling process needs to remove more conductive plating segments and dielectric layers. In order to ensure the processing efficiency, the processing precision can be relatively low, so the stubs cannot be completely removed. For example, as shown in FIG. 28, the preliminary back drilling structure can be formed by mechanical drilling, but due to the limitation of the minimum blade length of the mechanical drill bit 301 and the processing precision, part of the stubs 302 cannot be completely removed.

[0348] The stub detection device can refer to a device capable of non-contact measurement of the surface and internal structure of the circuit board.

[0349] In an exemplary embodiment, the stub detection device can include a CT (Computed Tomography) device or a CL (Computed Laminography) device.

[0350] The computer tomography device can scan the preliminary back drilling structure from multiple angles using X-rays, and process the scanning data by computer to determine the position and size of the stubs in the preliminary back drilling structure.

[0351] The computer laminography device is a micron focal point X-ray source device using computer laminography technology, which is called micro-focus CL or planar CT, and in some other embodiments, it is also called an X-ray detection system / device / device, or an X-ray detection system / device / device, etc. The name of the computer laminography device is not limited in this application. The computer laminography device can use X-rays to penetrate objects to obtain density distribution information inside the object. The computer laminography device can obtain a three-dimensional image of the internal structure distribution of the circuit board according to the absorption and scattering degree of X-rays by different material density differences inside the circuit board, and then determine the position and size of the stubs in the preliminary back drilling structure from the three-dimensional image to realize high-precision stub subtractive machining. It should be noted that this is only an exemplary description of the computer laminography device, and is not a limitation of the computer laminography device.

[0352] The stub position information can refer to the data description of the specific spatial position of the stubs in the preliminary back drilling structure after the preliminary back drilling process is completed. The stub position information can include at least one of the axial length, the circumferential distribution thickness, and the axial endpoint coordinates of the stubs.

[0353] Exemplarily, after the preliminary back drilling process is completed, the stub detection device can be controlled to scan the circuit board region corresponding to the preliminary back drilling structure to generate a cross-sectional image of the circuit board region corresponding to the preliminary back drilling structure. The stub position information of the stubs in the preliminary back drilling structure can be obtained by image processing and analysis of the cross-sectional image.

[0354] The preliminary back drilling structure corresponds to a circuit board area covering at least the preliminary back drilling structure and the stub in the preliminary back drilling structure.

[0355] In some possible implementations, the circuit board area within a certain range around each preliminary back drilling structure can be scanned before laser stub subtractive machining is performed on the preliminary back drilling structure, so as to obtain the stub position information of the stub in the preliminary back drilling structure.

[0356] In some possible implementations, the circuit board area within a certain range around each preliminary back drilling structure can be scanned before laser stub subtractive machining is performed on the preliminary back drilling structure, so as to obtain the stub position information of the stub in the preliminary back drilling structure.

[0357] The traditional way of estimating the stub position is affected by the superposition of errors in multiple links, including at least the machining accuracy of the circuit board itself, the measurement accuracy of the medium thickness, the preliminary back drilling accuracy, and the execution accuracy of the subsequent stub subtractive machining. In the present application, the stub is directly positioned by scanning the preliminary back drilling structure after the preliminary back drilling is completed, so the real position information of the stub can be obtained, and thus the machining accuracy and reliability of the whole process are effectively improved, and higher machining accuracy is achieved.

[0358] Step S2620, based on the stub position information, controlling the laser to subtractively machine the stub in the preliminary back drilling structure.

[0359] Exemplarily, after obtaining the stub position information, at least one laser processing parameter, such as the laser focal point position, the spot size, the laser power, the pulse duration and the pulse number, can be set according to the detected stub position information, and then the laser processing device is controlled to emit laser to the stub in the preliminary back drilling structure along the axis of the preliminary back drilling structure according to the set laser processing parameter, so as to precisely subtractively machine the stub in the preliminary back drilling structure to reach the preset target value.

[0360] Wherein, reaching the preset target value can mean that the length of the stub is less than or equal to the preset target value through further laser detection of the stub. The preset target value can be determined according to the detection accuracy of the stub detection device, the machining accuracy of the laser processing device, and the actual test result, which is not limited in the present embodiment.

[0361] It can be understood that an ideal back drilling process should be able to achieve the goal of near-zero stub to maximize signal integrity and electromagnetic compatibility to meet the needs of high-speed signal transmission, but in actual processing, the purpose of laser subtracting of the stub is to further reduce the size of the stub, and the actual effect is usually difficult to achieve zero stub.

[0362] In some feasible embodiments, in the case that the size of the structure to be processed is small and the laser can completely cover the stub, the laser can be controlled to be aligned with the center of the preliminary back drilling structure or the structure to be processed, and one or more laser pulses can be emitted to achieve the subtracting of the stub.

[0363] In some other feasible embodiments, in the case that the size of the structure to be processed is large and the laser cannot completely cover the stub, the trajectory planning can be performed according to the circumferential distribution of the stub, the laser can be controlled to deflect along the circumferential distribution of the stub according to the planned trajectory, and multiple laser pulses can be continuously emitted to achieve the subtracting of the stub.

[0364] In an exemplary embodiment, the laser includes an ultrafast laser.

[0365] The ultrafast laser can refer to a pulsed laser with a pulse width at the level of picoseconds, femtoseconds or attoseconds. The extremely short pulse width of the ultrafast laser enables it to deliver energy to the material surface in a very short time, achieving effective subtracting of the stub. In the case that the stub material is copper, a pulse width at the level of nanoseconds will still cause a relatively serious thermal effect, causing quality problems such as deformation of the circuit board, so the pulse width needs to reach the level of picoseconds or even femtoseconds to meet the quality requirements of the product.

[0366] In the above back drilling processing method, first, based on the preliminary back drilling structure on the circuit board, the stub detection device is controlled to scan the preliminary back drilling structure to obtain the stub position information of the stub in the preliminary back drilling structure, and the stub is positioned; and then the laser is controlled to subtract the stub in the preliminary back drilling structure based on the stub position information, achieving local and accurate removal of the stub. Compared with the traditional laser thickness measurement technology, the present application scans the actual stub in the preliminary back drilling structure after forming the preliminary back drilling structure, which can achieve more accurate stub positioning. Compared with the traditional mechanical back drilling technology, the laser processing has the characteristics of high precision and non-contact, and can perform fine subtracting on the specified position without adding additional physical stress. In this way, by combining high-precision stub positioning and high-precision laser subtracting technology, the limitation of traditional mechanical back drilling in precision is broken, the error caused by inaccurate medium thickness measurement is avoided, the stub length can be controlled at a lower level, and the zero residual target in the ideal state is closer, so that the signal transmission quality and electromagnetic compatibility performance are significantly improved, and the stringent requirements of high-speed signal processing on the back drilling process are met.

[0367] In an exemplary embodiment, the preliminary back drilling structure comprises a back drilling hole, the back drilling hole comprising a conductive via segment and a back drilling segment; the spot size of the laser is smaller than the aperture of the back drilling segment and larger than the aperture of the conductive via segment.

[0368] The back drilling hole can refer to the conductive via after back drilling. The back drilling hole comprises a conductive via segment that is not removed by back drilling in the conductive via to be processed, and a non-conductive via segment formed after the conductive plating segment is removed by back drilling.

[0369] The conductive via is usually small in size. In the case that the laser can completely cover the stub, the stub subtractive machining can be achieved by emitting one or more laser pulses from a single point.

[0370] In this case, as shown in FIG. 29, the spot size of the laser 401 needs to be larger than the aperture of the conductive via segment 403 to ensure that the single laser 401 can completely cover the stub; at the same time, the spot size of the laser 401 needs to be smaller than the aperture of the back drilling segment 402 to ensure that the laser 401 can pass through the non-conductive via segment 402 and directly act on the stub.

[0371] In this embodiment, in the case that the laser can completely cover the stub, the stub subtractive machining is achieved by emitting laser pulses from a single point, which has higher processing efficiency because there is no need for laser deflection control. On the other hand, since the energy concentration and heat accumulation caused by acceleration and deceleration in the laser deflection process are avoided, the risk of thermal damage to the surrounding material can be reduced, thereby further improving the processing precision and the quality of the hole wall.

[0372] In an exemplary embodiment, the length of the stub after laser subtractive machining is smaller than or equal to the larger one of the detection precision value of the stub detection device and the processing precision value of the laser.

[0373] The detection precision value can refer to the size precision level that the stub detection device can achieve, i.e., the degree of deviation between the actual size of the product and the detected size.

[0374] The processing precision value can refer to the size precision level that the laser processing can achieve, i.e., the degree of deviation between the actual processed product size and the design required size.

[0375] In the process of laser subtractive machining of the stub, it is necessary to ensure that the electrical performance of the circuit board after the stub subtractive machining is not damaged, i.e., excessive subtractive machining should be avoided. On this basis, the length of the stub is shortened as much as possible.

[0376] In the embodiment, the machining precision of the laser subtractive stub is mainly limited by the detection precision of the stub detection and the machining precision of the laser. In order to ensure that the electrical performance of the circuit board after stub subtractive machining is not damaged, in the case that the detection precision of the stub detection is greater than the machining precision of the laser, the stub length can be controlled within the detection precision of the stub detection; in the case that the detection precision of the stub detection is less than the machining precision of the laser, the stub length can be controlled within the machining precision of the laser.

[0377] For example, assuming that the detection precision of the stub detection is L1 and the machining precision of the laser is L2, if L1 is less than L2, the stub length after laser subtractive machining can be controlled within L2, but if controlled within L1, the non-stub area may be damaged due to laser machining deviation, affecting the electrical performance of the circuit board; if L1 is greater than L2, the stub length after laser subtractive machining can be controlled within L1, but if controlled within L2, the non-stub area may be damaged due to stub detection deviation, affecting the electrical performance of the circuit board.

[0378] In the embodiment, by determining the length limit of the stub after laser subtractive machining, the stub length can be shortened as much as possible to improve the signal transmission quality and electromagnetic compatibility performance while ensuring that the electrical performance of the circuit board after stub subtractive machining is not damaged.

[0379] In an exemplary embodiment, the stub length after laser subtractive machining is less than or equal to 20 pm.

[0380] The stub is usually composed of a metal material, such as copper. To effectively remove such metal materials, the laser used needs to have a high energy density and a small spot size to achieve high-precision local machining. Therefore, the machining precision of the laser in stub subtractive machining applications is usually better than the detection precision of the stub detection device. For example, the detection precision of the commonly used stub detection device, such as the X-ray-based computer tomography equipment, can generally reach ±10 pm; while the machining precision of the picosecond laser system used for precision micro-machining can reach several microns or even sub-micron level, which is significantly better than the resolution of the detection device.

[0381] Based on this, in actual application, if the above high-precision laser is used for stub removal and combined with the stub position information provided by the detection device, the stub length after laser subtractive machining can be controlled to be less than 20 pm. This value is significantly better than the 2 mil (about 50 pm) level that can be achieved by the traditional mechanical back drilling machining combined with the Smart Mapping technology, and can more effectively meet the process requirements of extremely low stub length for high-speed signal transmission.

[0382] In an exemplary embodiment, based on the stub position information, the laser is controlled to subtractively process the stub in the preliminary back drilling structure, including steps S21-S23, wherein:

[0383] In step S21, based on the stub position information and the structure information of the circuit board, the material information of the dielectric layer, the material information of the conductive plating layer and the thickness information of the conductive plating layer corresponding to the stub are determined.

[0384] The structure information of the circuit board can refer to the physical structure data of the circuit board involved in the design and manufacturing process, such as the composition, thickness distribution and conductive layer arrangement of each layer of material.

[0385] It should be noted that in order to ensure effective subtraction of the stub, the spot size of the laser is usually larger than the diameter of the stub, so the laser usually needs to subtract not only the stub but also the circuit board material around the stub. Therefore, when setting the laser processing parameters, the stub and the circuit board material around the stub need to be considered.

[0386] Exemplarily, after the preliminary back drilling process is completed and the stub position information is obtained, the area where the current stub is located can be matched according to the stub position information, so as to query the dielectric layer material, the conductive plating layer material and the conductive plating layer thickness in the area where the stub is located from the structure information of the circuit board.

[0387] In step S22, the laser processing parameters are set according to the stub position information, the dielectric layer material information, the conductive plating layer material information and the conductive plating layer thickness information.

[0388] The laser processing parameters can refer to at least one of the process parameters required for laser subtraction of the stub in the preliminary back drilling structure, which can include at least one of the laser focal point position, the spot size, the laser power, the pulse duration and the number of pulse emissions.

[0389] In an exemplary embodiment, the laser processing parameters include the laser power and the number of laser pulse emissions.

[0390] The laser power and the number of laser pulse emissions together determine the total laser energy acting on the stub. In order to ensure that the laser can effectively remove the stub and the circuit board material in the area where the stub is located, the total energy value must be reasonably set. Therefore, when setting the laser processing parameters, at least the size of the laser power and the number of pulse emissions need to be determined to ensure that the laser has enough energy to completely subtract the stub, while avoiding affecting the processing quality and efficiency due to insufficient or excessive energy.

[0391] Exemplarily, after the die stub corresponding dielectric layer material information, conductive plating layer material information and conductive plating layer thickness information, the laser processing parameters capable of effectively reducing the die stub can be determined according to the die stub position information, the die stub corresponding dielectric layer material information, the conductive plating layer material information and the conductive plating layer thickness information, and the laser processing device is set based on the laser processing parameters.

[0392] In step S23, the laser is controlled to reduce the die stub in the preliminary back drilling structure according to the set laser processing parameters.

[0393] Exemplarily, after the laser processing parameters are set, the laser processing device can be controlled to emit laser to the die stub in the preliminary back drilling structure along the axial direction of the preliminary back drilling structure according to the set laser processing parameters, so as to accurately reduce the die stub in the preliminary back drilling structure by laser.

[0394] In this embodiment, by comprehensively analyzing the die stub position, material type and die stub thickness, the most suitable laser parameters can be dynamically set to avoid processing failure or structure damage caused by improper parameters. Compared with the traditional single parameter processing mode, the present embodiment can adapt to the current actual situation, dynamically adjust the laser processing parameters, and significantly improve the die stub reduction efficiency and quality.

[0395] It should be understood that, although each step in the flowchart involved in the above-mentioned embodiments is displayed in sequence according to the arrow, these steps are not necessarily executed in sequence according to the arrow. Unless otherwise stated herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least part of the steps in the flowchart involved in the above-mentioned embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or steps or stages in other steps.

[0396] Based on the same inventive concept, the present embodiment also provides a back drilling processing method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more back drilling processing method embodiments provided below can refer to the limitations of the back drilling processing method described above, and will not be repeated here.

[0397] In an exemplary embodiment, the method comprises:

[0398] Obtaining die stub position information, wherein the die stub position information is obtained by scanning the preliminary back drilling structure on the circuit board by a die stub detection device;

[0399] Based on the residual post position information, the laser is controlled to perform subtractive machining on the residual post in the preliminary back drilling structure.

[0400] In an exemplary embodiment, the preliminary back drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, and controlling the preliminary back drilling processing device to perform back drilling processing on the structure to be processed to form the preliminary back drilling structure; the preliminary back drilling structure includes a back drilling hole, and the back drilling hole includes a conductive via segment and a back drilling segment; the spot size of the laser is smaller than the aperture of the back drilling segment and larger than the aperture of the conductive via segment.

[0401] In an exemplary embodiment, the length of the residual post after laser subtractive machining is less than or equal to the greater one of the detection accuracy value of the residual post detection device and the machining accuracy value of the laser.

[0402] In an exemplary embodiment, the length of the residual post after laser subtractive machining is less than or equal to 20 μm.

[0403] In an exemplary embodiment, based on the residual post position information, the laser is controlled to perform subtractive machining on the residual post in the preliminary back drilling structure, including:

[0404] Based on the residual post position information and the structure information of the circuit board, the medium layer material information, the conductive plating layer material information, and the conductive plating layer thickness information corresponding to the residual post are determined;

[0405] According to the residual post position information, the medium layer material information, the conductive plating layer material information, and the conductive plating layer thickness information, the laser processing parameters are set;

[0406] The laser is controlled to perform subtractive machining on the residual post in the preliminary back drilling structure according to the set laser processing parameters.

[0407] In an exemplary embodiment, the laser processing parameters include laser power and laser pulse number.

[0408] In an exemplary embodiment, the residual post detection device includes a computer tomography device or a computer layer imaging device.

[0409] In an exemplary embodiment, the laser includes an ultrafast laser.

[0410] Based on the same inventive concept, the embodiments of the present application also provide a back drilling processing method, and the implementation schemes of the problems provided by the device are similar to the implementation schemes described in the above method. Therefore, the specific limitations in one or more back drilling processing method embodiments provided below can refer to the limitations of the back drilling processing method described above, and will not be described here.

[0411] In an exemplary embodiment, the method includes:

[0412] The residual post position information is used for controlling the laser to subtract the residual post in the preliminary back drilling structure to reach a preset target value.

[0413] The residual post position information is used for controlling the laser to subtract the residual post in the preliminary back drilling structure to reach a preset target value.

[0414] In an exemplary embodiment, the preliminary back drilling structure on the circuit board is processed by the following steps: positioning a structure to be processed on the circuit board, controlling a preliminary back drilling processing device to back drill the structure to be processed to form the preliminary back drilling structure; the preliminary back drilling structure includes a back drilling hole, and the back drilling hole includes a conductive via segment and a back drilling segment; the spot size of the laser is smaller than the aperture of the back drilling segment and larger than the aperture of the conductive via segment.

[0415] In an exemplary embodiment, the length of the residual post after laser subtracting is less than or equal to the greater one of the detection accuracy value of the residual post detection device and the processing accuracy value of the laser.

[0416] In an exemplary embodiment, the length of the residual post after laser subtracting is less than or equal to 20 μm.

[0417] In an exemplary embodiment, based on the residual post position information, the laser is controlled to subtract the residual post in the preliminary back drilling structure, including:

[0418] Based on the residual post position information and the structure information of the circuit board, the medium layer material information, the conductive plating layer material information, and the conductive plating layer thickness information corresponding to the residual post are determined;

[0419] According to the residual post position information, the medium layer material information, the conductive plating layer material information, and the conductive plating layer thickness information, the laser processing parameters are set;

[0420] The laser is controlled to subtract the residual post in the preliminary back drilling structure according to the set laser processing parameters.

[0421] In an exemplary embodiment, the laser processing parameters include laser power and laser pulse number.

[0422] In an exemplary embodiment, the residual post detection device includes a computer tomography device or a computer layer imaging device.

[0423] In an exemplary embodiment, the laser includes an ultrafast laser.

[0424] Based on the same inventive concept, the embodiments of the present application also provide a back drilling device for implementing the back drilling method described above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more back drilling device embodiments provided below can refer to the limitations of the back drilling method described above, which will not be repeated here.

[0425] In an exemplary embodiment, the present application provides a back drilling device, comprising:

[0426] a laser processing device configured to subtract material from the stub in the preliminary back drilling structure on the circuit board based on the stub position information.

[0427] In an exemplary embodiment, as shown in FIG. 30, the back drilling device includes a stub detection device 502 and a laser processing device 504, and wherein:

[0428] The stub detection device 502 is configured to detect the stub position information of the stub in the preliminary back drilling structure by scanning the preliminary back drilling structure on the circuit board.

[0429] The laser processing device 504 is configured to subtract material from the stub in the preliminary back drilling structure based on the stub position information, wherein the stub position information is obtained by scanning the preliminary back drilling structure on the circuit board by the stub detection device.

[0430] In some feasible implementations, the preliminary back drilling device can be a mechanical preliminary back drilling device or a laser processing device. In the case where the preliminary back drilling device is a laser processing device, the laser processing device for preliminary back drilling and the laser processing device for stub subtraction can be the same device, or two different devices with different processing precisions.

[0431] In an exemplary embodiment, the preliminary back drilling structure on the circuit board is formed by positioning the structure to be processed on the circuit board by the preliminary back drilling device and back drilling the structure to be processed; the preliminary back drilling structure includes a back drilling hole, and the back drilling hole includes a conductive via segment and a back drilling segment; the spot size of the laser is smaller than the aperture of the back drilling segment and larger than the aperture of the conductive via segment.

[0432] In an exemplary embodiment, the length of the stub after laser subtraction is less than or equal to the larger one of the detection precision value of the stub detection device and the processing precision value of the laser.

[0433] In an exemplary embodiment, the length of the stub after laser subtraction is less than or equal to 20 μm.

[0434] In an example embodiment, the back drilling apparatus further comprises a controller configured to:

[0435] based on the stub location information and the structure information of the circuit board, determine stub corresponding dielectric layer material information, conductive plating layer material information and conductive plating layer thickness information;

[0436] based on the stub location information, the dielectric layer material information, the conductive plating layer material information and the conductive plating layer thickness information, set laser processing parameters;

[0437] control the laser to perform subtractive machining on the stub in the preliminary back drilling structure according to the set laser processing parameters.

[0438] In an example embodiment, the laser processing parameters include laser power and laser pulse number.

[0439] In an example embodiment, the stub detection device includes a computer tomography device or a computer layer imaging device.

[0440] In an example embodiment, the laser includes an ultrafast laser.

[0441] Based on the same inventive concept, the embodiments of the present application also provide a back drilling apparatus for implementing the above-mentioned back drilling method. The implementation scheme for solving the problem provided by the apparatus is similar to the implementation scheme described in the above-mentioned method, so the specific limitations in one or more back drilling apparatus embodiments provided below can refer to the limitations of the back drilling method described above, which will not be repeated here.

[0442] In an example embodiment, the present application provides a back drilling apparatus comprising:

[0443] a stub detection device configured to detect stub location information of a stub in a preliminary back drilling structure on a circuit board by scanning the preliminary back drilling structure, wherein the stub location information is used to control a laser processing device to perform subtractive machining on the stub in the preliminary back drilling structure to achieve a preset target value.

[0444] In an example embodiment, the back drilling apparatus further comprises:

[0445] a laser processing device configured to perform subtractive machining on the stub in the preliminary back drilling structure based on the stub location information, wherein the stub location information is obtained by scanning the preliminary back drilling structure on the circuit board by the stub detection device.

[0446] In some possible implementations, the preliminary back drilling device can be a mechanical preliminary back drilling device or a laser processing device. In the case where the preliminary back drilling device is a laser processing device, the laser processing device for preliminary back drilling and the laser processing device for residual stub material removal can be the same device or two different devices with different processing precisions.

[0447] In an example embodiment, the preliminary back drilling structure on the circuit board is formed by positioning the structure to be processed on the circuit board by the preliminary back drilling device and performing back drilling on the structure to be processed. The preliminary back drilling structure includes a back drilling hole, and the back drilling hole includes a conductive via segment and a back drilling segment. The spot size of the laser is smaller than the aperture of the back drilling segment and larger than the aperture of the conductive via segment.

[0448] In an example embodiment, the length of the residual stub after laser material removal is less than or equal to the greater one of the detection precision value of the residual stub detection device and the processing precision value of the laser.

[0449] In an example embodiment, the length of the residual stub after laser material removal is less than or equal to 20 μm.

[0450] In an example embodiment, the back drilling device further includes a controller configured to:

[0451] determine, based on the residual stub position information and the structure information of the circuit board, the dielectric layer material information, the conductive plating layer material information, and the conductive plating layer thickness information corresponding to the residual stub;

[0452] set the laser processing parameters according to the residual stub position information, the dielectric layer material information, the conductive plating layer material information, and the conductive plating layer thickness information;

[0453] control the laser to perform material removal on the residual stub in the preliminary back drilling structure according to the set laser processing parameters.

[0454] In an example embodiment, the laser processing parameters include laser power and laser pulse number.

[0455] In an example embodiment, the residual stub detection device includes a computer tomography device or a computer layer imaging device.

[0456] In an example embodiment, the laser includes an ultrafast laser.

[0457] In an example embodiment, the present application provides a circuit board processed by the above method.

[0458] In an example embodiment, the present application provides a computer device, which can be a terminal, and its internal structure can be as shown in FIG. 31. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. Among them, the processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The input / output interface of the computer device is used to exchange information between the processor and external devices. The communication interface of the computer device is used to communicate with external terminals in a wired or wireless manner. The wireless manner can be achieved through WIFI, mobile cellular network, near field communication (Near Field Communication, NFC) or other technologies. The computer program is executed by the processor to implement a back drilling processing method. The display unit of the computer device is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device. It can also be an external keyboard, touchpad or mouse, etc.

[0459] In an example embodiment, the present application provides a circuit board laser processing method. In this embodiment, the execution subject of the method is a terminal. The terminal can be a circuit board laser processing device, or another terminal capable of controlling the circuit board laser processing device, such as various personal computers, notebook computers, smart phones, tablet computers, Internet of Things devices and portable wearable devices, etc. The Internet of Things device can be a smart speaker, a smart TV, a smart air conditioner, a smart vehicle device, a projection device, etc. The portable wearable device can be a smart watch, a smart bracelet, a head-mounted device, etc. The head-mounted device can be a virtual reality (Virtual Reality, VR) device, an augmented reality (Augmented Reality, AR) device, smart glasses, etc. It can be understood that the execution subject of the method can also be a server, and can also be a system including a terminal and a server, and the implementation is realized through the interaction of the terminal and the server.

[0460] In this embodiment, as shown in FIG. 32, the method includes the following steps S3310-S3330. Among them:

[0461] In step S3310, measured thickness data, theoretical thickness data, and theoretical process parameter values of the to-be-processed circuit board are obtained, where the measured thickness data is obtained by scanning the to-be-processed circuit board by a scanning device, and the theoretical process parameter values are determined based on the theoretical thickness data.

[0462] It can be understood that, since laser drilling is a single-point processing, if the micro-hole is not conducted due to thickness deviation, it will directly lead to process defects. However, for other continuous laser processing processes such as laser slotting and laser cutting, if one point is not conducted, it can be compensated by the processing of adjacent points, and the overall processing effectiveness can still be ensured. Therefore, the above technical problem is not easy to find in other continuous laser processing processes.

[0463] Although the present embodiment is proposed based on laser drilling, it can also be applied to other laser processing such as laser slotting and laser cutting, and can effectively improve the processing accuracy of each processing point, thereby improving the processing consistency. Therefore, the laser processing referred to in the present embodiment can include laser drilling, laser slotting, laser cutting, and the like.

[0464] The to-be-processed circuit board can refer to a PCB that needs to be processed by laser, such as a high-density interconnection circuit board, a multi-layer circuit board, and the like.

[0465] The to-be-processed circuit board can include at least one conductive material layer and at least one insulating material layer. The conductive material layer can refer to a layer structure in the PCB for transmitting electrical signals or current, which can be composed of highly conductive metals or non-metals, such as copper, aluminum, silver, and the like. The insulating material layer can refer to a non-conductive medium in the PCB for isolating the conductive layer, which can effectively prevent short circuits and provide mechanical support.

[0466] Scanning the to-be-processed circuit board can refer to using a scanning device to non-contact measure the surface and internal structure of the to-be-processed circuit board.

[0467] The scanning device can include optical detection equipment, laser detection equipment, and the like.

[0468] In some possible implementations, the scanning device can include a computer tomography scanning device. The to-be-processed circuit board can be subjected to CT (Computed Tomography) scanning to obtain measured thickness data of the to-be-processed circuit board. The computer tomography scanning device can scan the inside of the to-be-processed circuit board from multiple angles using X-rays, and process the scanning data by a computer to generate cross-sectional data of the to-be-processed circuit board.

[0469] The measured thickness data can refer to the thickness values of each conductive material layer and each insulating material layer in the to-be-processed circuit board actually measured by scanning.

[0470] The theoretical thickness data can refer to standard thickness values of each conductive material layer and each insulating material layer in a design file or a process specification of the circuit board to be processed.

[0471] In one of the embodiments, the circuit board to be processed includes at least one conductive material layer and at least one insulating material layer; the theoretical thickness data includes theoretical thickness values of each conductive material layer and theoretical thickness values of each insulating material layer; and the measured thickness data includes measured thickness values of each conductive material layer and measured thickness values of each insulating material layer.

[0472] The theoretical process parameter values can refer to at least one of laser processing parameters, such as laser energy, laser pulse number, and focal length, which are calculated in advance based on the theoretical thickness data.

[0473] Before laser processing, the theoretical process parameter values of laser processing can be designed or calculated by a relevant designer or model according to the theoretical characteristic data of the circuit board to be processed and actual processing requirements. The theoretical characteristic data of the circuit board to be processed includes the theoretical thickness data of the circuit board to be processed. For example, for copper layers with different thicknesses, the process parameter values such as laser energy, pulse width, pulse number, and focal length required for processing can be different.

[0474] In the related art, the laser processing equipment is usually directly controlled to process the circuit board to be processed according to the theoretical process parameter values. However, there can be a deviation between the actual thickness and the theoretical thickness of the circuit board to be processed after actual processing. If the actual thickness is less than the theoretical thickness, it means that the time or energy required for laser to penetrate the target material layer is reduced. If the processing is still performed according to the theoretical process parameter values, the laser can continue to act on the lower material layer after penetrating the target material layer, and even burn through the lower material layer. If the actual thickness is greater than the theoretical thickness, it means that the laser needs to penetrate a thicker material. If the processing is still performed according to the theoretical process parameter values, the laser can not be able to completely penetrate the entire target material layer, resulting in the situation that the bottom of the blind hole is not punched through.

[0475] For example, during the laser processing, the circuit board to be processed can be placed on a processing platform by manual, a conveying device, a mechanical hand, or a robot, and then a scanning device can be used to scan the circuit board to be processed comprehensively or partially to obtain the measured thickness data. The measured thickness data obtained can be directly applied to guide subsequent laser processing, or can be stored in a storage of a terminal for reading in subsequent laser processing. The scanning range covers at least each processing point, that is, the measured thickness data includes at least a measured copper thickness value at each processing point. During the laser processing, the measured thickness data of the circuit board to be processed, the theoretical thickness data, and the theoretical process parameter values determined based on the theoretical thickness data can be obtained.

[0476] The actual thickness data of the to-be-processed circuit board affected by the process fluctuation can be obtained through scanning, so as to avoid the problem of process parameter mismatch caused by the incoming material process fluctuation.

[0477] In some possible implementation manners, the obtaining manner of the theoretical thickness data of the to-be-processed circuit board and the theoretical process parameter value can include at least one of the following: obtaining from a design file pre-stored in a terminal memory; obtaining from an external terminal through a communication connection with the external terminal; reading from a data carrier on the to-be-processed circuit board.

[0478] In step S3320, the theoretical process parameter value is adjusted according to the deviation between the actual thickness data and the theoretical thickness data, to obtain a target process parameter value.

[0479] The target process parameter value can refer to a process parameter value adjusted according to the actual thickness data.

[0480] For example, after obtaining the theoretical process parameter value, the target actual thickness data and the target theoretical thickness data required for adjusting the process parameter value can be selected from the obtained actual thickness data and the theoretical thickness data according to the preset corresponding relationship between the process parameter adjustment value and the thickness deviation; then, the thickness deviation value between the target actual thickness data and the target theoretical thickness data corresponding to each process parameter value is calculated; then, the thickness deviation value is converted into the process parameter adjustment value according to the preset corresponding relationship between the process parameter adjustment value and the thickness deviation, and the theoretical process parameter value is adjusted according to the process parameter adjustment value, to obtain the target process parameter value.

[0481] The dynamic parameter adjustment can effectively compensate for the thickness deviation, ensure that different thickness regions can be processed by more accurate process parameters, and improve the laser processing consistency.

[0482] In step S3330, the laser processing device is controlled to process the to-be-processed circuit board according to the target process parameter value.

[0483] The laser processing device can refer to a device capable of performing non-contact precision processing on the circuit board by using a high-energy laser beam.

[0484] For example, after determining the target process parameter value, the optimized target process parameter value can be imported into the control system of the laser processing device, and the control system can move the laser beam to the corresponding processing point according to a preset program. At each processing point, the control system automatically calls the target process parameter value corresponding to the processing point to perform processing.

[0485] In the laser processing method of the circuit board, first, measured thickness data, theoretical thickness data and theoretical process parameter values of the circuit board to be processed are obtained, wherein the measured thickness data is obtained by scanning the circuit board to be processed by a scanning device, and the theoretical process parameter values are determined based on the theoretical thickness data. In this way, no matter how the process of processing the circuit board to be processed fluctuates, the measured thickness of the circuit board to be processed is determined through personalized detection of the circuit board to be processed after the process fluctuates. Then, the target process parameter values are obtained by adjusting the theoretical process parameter values according to the deviation between the measured thickness data and the theoretical thickness data, and the laser processing device is controlled to process the circuit board to be processed according to the target process parameter values, thereby realizing self-adaptive adjustment of the actual processing parameters of the laser processing device. In this way, through personalized detection of the thickness data and self-adaptive adjustment of the processing parameters, the situation of non-penetration of the material or excessive processing caused by process fluctuation of the incoming material during laser processing can be effectively overcome, thereby significantly improving the quality and consistency of laser processing, meeting the increasing demand for size precision of micro-holes and quality of hole walls of high-quality blind holes, and promoting the development of high-quality blind holes.

[0486] In an exemplary embodiment, the theoretical thickness data and the theoretical process parameter values of the circuit board to be processed are obtained, comprising:

[0487] The theoretical thickness data and the theoretical process parameter values of the circuit board to be processed are read from the data carrier on the circuit board to be processed.

[0488] It should be noted that at present, the data designed or determined in advance is usually stored or imported in the terminal memory and called as needed during processing. However, the data stored in the terminal is separated from the physical board, and if a strict binding relationship is not established or there is deviation in identifying the physical board, the process parameters will not match the physical object, causing material mixing problems and seriously affecting product quality control.

[0489] The data carrier can refer to a physical medium capable of storing data, and can include at least one of a bar code, a radio frequency identification tag and a near field communication tag.

[0490] In some feasible embodiments, the data carrier can be generated based on the processing information including the theoretical thickness data and the theoretical process parameter values before the laser processing of the circuit board, and the data carrier can be printed, etched or embedded in the corresponding circuit board to be processed. For example, the theoretical thickness data and the theoretical process parameter values of the circuit board A1 to be processed can be encoded to generate a two-dimensional code B1, and then the two-dimensional code B1 can be printed or etched on the surface of the circuit board A1 to be processed. For another example, the theoretical thickness data and the theoretical process parameter values of the circuit board A2 to be processed can be written into a radio frequency identification tag B2, and then the radio frequency identification tag B2 can be pasted or embedded in the circuit board A2 to be processed.

[0491] For example, in the process of laser processing, the circuit board to be processed can be placed on the processing platform by manual, conveying device, manipulator or robot, and then the data carrier on the circuit board to be processed is positioned and recognized by visual sensor or near field antenna, and the theoretical thickness data and theoretical process parameter value of the circuit board to be processed are read from the data carrier.

[0492] In some possible embodiments, the adjusted target process parameter value can also be stored in the data carrier on the circuit board to be processed. The data carrier for storing the target process parameter value can be the same as or different from the data carrier for storing the theoretical thickness data and the theoretical process parameter value.

[0493] In some possible embodiments, the data carrier can include a read-only data carrier and a read-write data carrier. The data in the read-only data carrier can only be read, but cannot be modified, deleted or written with new data. The data in the read-write data carrier can be read, modified, deleted, etc., and new data can also be written into the read-write data carrier.

[0494] In some possible embodiments, the data carrier belongs to a read-only data carrier; the laser processing device is controlled to process the circuit board to be processed according to the target process parameter, including: generating a second data carrier based on the target process parameter, and processing the second data carrier on the circuit board to be processed, wherein the second data carrier belongs to a read-only data carrier; the laser processing device is controlled to read the target process parameter from the second data carrier on the circuit board to be processed, and process the circuit board to be processed according to the target process parameter.

[0495] In some possible embodiments, the data carrier belongs to a read-write data carrier; the laser processing device is controlled to process the circuit board to be processed according to the target process parameter, including: writing the target process parameter into the data carrier; the laser processing device is controlled to read the target process parameter from the data carrier on the circuit board to be processed, and process the circuit board to be processed according to the target process parameter.

[0496] In the embodiment, the theoretical thickness data and the theoretical process parameter value of the circuit board to be processed are stored in the data carrier on the circuit board to be processed, so that the strong binding of information and the board is realized, and the parameter confusion problem is fundamentally avoided.

[0497] In an example embodiment, the data carrier is used to store the information storage link corresponding to the circuit board to be processed; before the laser processing device is controlled to process the circuit board to be processed according to the target process parameter value, the method further includes:

[0498] write the target process parameter value into the information storage link corresponding to the to-be-processed circuit board; read the information storage link from the data carrier on the to-be-processed circuit board, and obtain the target process parameter value by accessing the information storage link.

[0499] It should be noted that, in the process of laser processing of the to-be-processed circuit board, at least two steps of scanning and processing are included, and the two steps can be continuously performed, that is, for each to-be-processed circuit board, laser processing is performed immediately after scanning, in which case, the measured thickness data obtained by scanning and the target process parameter value determined based on the measured thickness data can be directly imported into the laser processing equipment and applied to laser processing of the to-be-processed circuit board. However, the two steps can also be performed independently, for example, a scanning and processing platform and a processing platform can be separately provided, and other processing platforms can also be provided. In addition to obtaining theoretical thickness data, scanning can also obtain other information, and the information obtained by scanning can be used to determine the target process parameter value of laser processing or provide a reference for other processing processes. In this case, scanning and laser processing are performed independently, which is more helpful to provide overall scheduling flexibility and processing efficiency. However, in this case, to ensure the accuracy of subsequent processing steps, a strong binding between the target process parameter value and the to-be-processed circuit board needs to be established.

[0500] The cost of a read-write type data carrier is generally high, and the required occupied space in the to-be-processed circuit board is large, which is not conducive to the miniaturization development of the circuit board. The method of generating a new data carrier based on the target process parameter value needs to process multiple data carriers on the to-be-processed circuit board, which not only increases the processing procedure, but also increases the occupied space and may cause the theoretical thickness data in the data carrier to be incorrectly identified during subsequent processing.

[0501] The information storage link can refer to a URL (Uniform Resource Locator, uniform resource locator) or a unique identifier pointing to an online database or cloud service storing information related to the to-be-processed circuit board. The information storage link is stored in the data carrier, and the data stored in the information storage link can be read and written, but the change of the data stored in the information storage link will not affect the information storage link itself. In this way, the target process parameter value can be written into the same data carrier without modifying the data stored in the data carrier.

[0502] Exemplarily, in the process of laser processing, the circuit board to be processed can be placed on a scanning processing platform by manual, conveying device, manipulator or robot, and then scanned by a scanning device to obtain the measured thickness data. The information storage link specific to the circuit board to be processed can be read from the data carrier on the circuit board to be processed, and the theoretical thickness data and the theoretical process parameter value of the circuit board to be processed can be obtained from the information storage link. The target process parameter value of the circuit board to be processed can be determined based on the measured thickness data, the theoretical thickness data and the theoretical process parameter value.

[0503] After obtaining the target process parameter value, the target process parameter value can be written into the information storage link, or the theoretical process parameter value stored in the information storage link can be replaced by the target process parameter value.

[0504] Further, before the laser processing device executes the laser processing program, the circuit board to be processed can be placed on a processing platform by manual, conveying device, manipulator or robot, and then the information storage link specific to the circuit board to be processed can be read from the data carrier on the circuit board to be processed, and the target process parameter value of the circuit board to be processed can be obtained from the information storage link. The obtained target process parameter value can be imported into the control system of the laser processing device, and the control system of the laser processing device can perform laser processing on the circuit board to be processed according to the target process parameter value.

[0505] In the embodiment, by writing the information storage link into the data carrier, whether it is a read-write type data carrier or a read-only type data carrier, one data carrier can be used to realize strong binding of information and board and flexible adjustment of data written therein. Thus, the occupied space of the data carrier can be effectively reduced, which is conducive to the miniaturization development of the circuit board.

[0506] In an exemplary embodiment, as shown in FIG. 33, the circuit board to be processed is provided with a plurality of processing points, and the target process parameter value includes a target point process parameter value corresponding to each processing point. The measured thickness data includes measured point thickness data corresponding to each processing point.

[0507] The target process parameter value is obtained by adjusting the theoretical process parameter value according to the deviation between the measured thickness data and the theoretical thickness data, including steps S3310-S3320.

[0508] Step S3310, extracting the measured point thickness data corresponding to each processing point from the measured thickness data.

[0509] The processing point can refer to a specific position on the circuit board to be processed that needs to be processed by laser.

[0510] The measured point thickness data can refer to the thickness values of each conductive material layer and each insulating material layer corresponding to each processing point on the to-be-processed circuit board actually measured by scanning. It can be understood that the measured point thickness data can be determined based on the thickness values of each conductive material layer and each insulating material layer in the area covered by the processing point, or can be determined based on the thickness values of each conductive material layer and each insulating material layer in the area covered by the processing point and in the preset expansion area around the processing point.

[0511] In some possible embodiments, the measured point thickness data can refer to the average of the measured thickness values in the measured area corresponding to the processing point. For example, assuming that the to-be-processed circuit board includes conductive material layers L1 and L2, and insulating material layers L3 and L4, by scanning, the measured thickness values of two positions D1 and D2 in the measured area corresponding to a certain processing point are obtained, including the measured thickness value H1 of L1 measured at the D1 position, the measured thickness value H2 of L2 measured at the D1 position, the measured thickness value H3 of L3 measured at the D1 position, the measured thickness value H4 of L4 measured at the D1 position, the measured thickness value H5 of L1 measured at the D2 position, the measured thickness value H6 of L2 measured at the D2 position, the measured thickness value H7 of L3 measured at the D2 position, and the measured thickness value H8 of L4 measured at the D2 position, the average of H1 and H5 can be determined as the measured point thickness data of L1 corresponding to the processing point, and the measured point thickness data of each conductive material layer and each insulating material layer corresponding to the processing point can be determined in the same way.

[0512] The target point process parameter value can refer to the process parameter value obtained by optimizing the theoretical process parameter value corresponding to the processing point according to the measured thickness data corresponding to the processing point.

[0513] Exemplarily, in the thickness measurement scanning process, the to-be-processed circuit board can be comprehensively detected to obtain the measured thickness data containing the thickness values of each position on the to-be-processed circuit board, and then the measured point thickness data corresponding to each processing point can be queried and extracted from the measured thickness data according to the position information of the processing point.

[0514] In step S3320, the theoretical process parameter value is adjusted according to the deviation between the measured point thickness data corresponding to each processing point and the theoretical thickness data, to obtain the target point process parameter value of each processing point.

[0515] Exemplarily, for each processing point, the corresponding relationship between the preset process parameter adjustment value and the thickness deviation can be used to select the target measured point thickness data and the target theoretical thickness data required for adjusting the process parameter value from the obtained measured point thickness data and the theoretical thickness data; then, the thickness deviation value between the target measured point thickness data and the target theoretical thickness data corresponding to each process parameter value is calculated; then, the thickness deviation value is converted into the process parameter adjustment value according to the preset corresponding relationship between the process parameter adjustment value and the thickness deviation, and the theoretical process parameter value is adjusted according to the process parameter adjustment value to obtain the target process parameter value.

[0516] It can be understood that the theoretical thickness data corresponding to different processing points can be the same or different. In the case that the theoretical thickness data corresponding to each processing point is the same, for each processing point, the target measured point thickness data corresponding to the processing point can be compared with the same theoretical thickness data for deviation. In the case that the theoretical thickness data corresponding to each processing point is different, the theoretical point thickness data corresponding to each processing point needs to be determined from the theoretical thickness data, and the target measured point thickness data corresponding to each processing point is compared with the same theoretical point thickness data corresponding to the processing point for deviation.

[0517] The laser processing device is controlled to process the to-be-processed circuit board according to the target process parameter value, including steps S3330-S3340.

[0518] In step S3330, the laser processing device is set according to the target point process parameter value corresponding to each processing point.

[0519] Exemplarily, after the target point process parameter value corresponding to each processing point is determined, the optimized target point process parameter value can be imported into the control system of the laser processing device according to the processing point.

[0520] In step S3340, the laser processing device is controlled to process at the processing point according to the target point process parameter value set corresponding to each processing point.

[0521] Exemplarily, in the actual laser processing process, the control system of the laser processing device can move the laser beam to the corresponding processing point according to the preset program. At each processing point, the control system automatically calls the target point process parameter value corresponding to the processing point to perform processing.

[0522] In this embodiment, the scanning efficiency can be effectively improved by comprehensive scanning, thereby improving the processing efficiency. Furthermore, by matching the processing point position and determining the measured point thickness data, the processing accuracy of each processing point can be effectively ensured, and the laser processing quality is improved.

[0523] In an exemplary embodiment, at least part of the target point process parameter values are the same; the laser processing device is set according to the target point process parameter values corresponding to each processing point, including steps S33301-S33302, wherein:

[0524] Step S33301, based on the target point process parameter values, the processing points are divided into a plurality of to-be-processed groups, and the current to-be-processed group is determined from the to-be-processed groups. The target point process parameter values of the processing points belonging to the same to-be-processed group are the same.

[0525] It should be noted that at present, in the laser processing process, the processing points are usually sorted according to their positions, that is, the processing points are sorted with the minimum moving distance as the target, and then the laser processing device is sequentially set according to the sorting. However, according to the target point process parameter values adjusted according to the measured thickness data of each processing point, some of the target point process parameter values may be the same and some may be different. In this case, if the processing points with the same target point process parameter values are relatively dispersed, the setting parameters of the laser processing device need to be frequently modified, which is low in efficiency.

[0526] Among them, the to-be-processed group can refer to the set of processing points with the same target point process parameter values.

[0527] Exemplarily, according to the target point process parameter values corresponding to each processing point, all processing points can be grouped, the target points with the same target point process parameter values are divided into the same to-be-processed group, and the target points with different target point process parameter values are divided into different to-be-processed groups. Further, one is selected as the current to-be-processed group from the to-be-processed groups randomly or according to a preset processing sequence.

[0528] Step S33302, setting step: setting the laser processing device according to the target point process parameter values corresponding to the current to-be-processed group.

[0529] Exemplarily, after the current to-be-processed group is determined, the target point process parameter values corresponding to the current to-be-processed group can be imported into the control system of the laser processing device.

[0530] The laser processing device is controlled to process at each processing point according to the target point process parameter values corresponding to each processing point, including steps S33401-S33402, wherein:

[0531] Step S33401, controlling the laser processing device to process the processing points in the current to-be-processed group according to the target point process parameter values corresponding to the current to-be-processed group.

[0532] Exemplarily, the control system of the laser processing device can move the laser beam to each processing point corresponding to the current processing group in turn, and perform laser processing on each processing point according to the target point parameter value corresponding to the current processing group.

[0533] In step S33402, after processing all processing points in the current processing group, the current processing group is re-determined from the unprocessed processing groups, and the setting step is returned to be executed.

[0534] Exemplarily, after processing all processing points in the current processing group, the current processing group can be determined as a processed processing group, and then the current processing group can be re-determined from the unprocessed processing groups, and the setting step is returned to be executed until no unprocessed processing group is detected, it can be determined that all processing groups are processed, that is, the laser processing of the processing circuit board is completed.

[0535] In some possible implementations, as shown in FIG. 34, a plurality of processing points are arranged on the processing circuit board, the target point parameter values of the processing point 3401, the processing point 3403 and the processing point 3405 are the same, and the target point parameter values of the processing point 3402, the processing point 3404 and the processing point 3406 are the same; if the minimum moving distance is taken as the target, the processing points 3401, 3402, 3403, 3404, 3405 and 3406 should be processed in the order or in the reverse order, but in this way, the laser processing device needs to be adjusted once for each processing point; if the processing is performed according to the grouping, the processing points 3401, 3403, 3405, 3406, 3404 and 3402 can be processed in the order, in this way, the laser processing device needs to be adjusted only once after the processing point 3405 is processed, which greatly reduces the number of adjustments of the laser processing device.

[0536] In this embodiment, by dividing the processing points with the same target point parameter values into the same processing group, the continuous processing of the processing points in the group can be realized, which not only can effectively reduce the number of processing parameter adjustments of the laser processing device, but also can avoid pausing the deflection of the laser during the laser processing of the processing points in the group, because there is no need to wait for the adjustment of the laser processing device. Therefore, if a galvanometer is used for deflection, the time wasted by the start and stop of the galvanometer can be reduced. In summary, the processing efficiency can be effectively improved.

[0537] In an example embodiment, the theoretical process parameter value includes position information, size information and process offset information corresponding to each machining point, and the extracting of the measured point thickness data corresponding to each machining point from the measured thickness data includes steps S33101-S33103, wherein:

[0538] In step S33101, the measured area corresponding to each machining point is determined according to the position information, size information and process offset information corresponding to each machining point.

[0539] The position information can refer to the spatial coordinate information of the machining point on the to-be-processed circuit board. The size information can refer to the geometric parameters related to the machining point. The process offset information can refer to the offset amount of the actual machining position relative to the theoretical position due to positioning errors of the laser processing device or material deformation, etc., which can be determined according to experience or test results, etc.

[0540] The measured area can refer to a physical range that needs to be measured in thickness with the machining point as the center. The measured area can be a circle, a rectangle or other shapes, depending on the actual requirements of the aperture size and process tolerance, etc.

[0541] For example, for each machining point, the measured area corresponding to the machining point can be circled from the machining range of the to-be-processed circuit board according to the position information, size information and process offset information corresponding to the machining point, combined with a preset area division rule. The preset area division rule can be determined according to actual needs and test results, etc., for example, the measured area should cover the machining point and its ±1 aperture range, etc., which is not limited in the embodiment.

[0542] In step S33102, the measured area thickness data corresponding to each measured area is extracted from the measured thickness data.

[0543] For example, the measured area thickness data corresponding to each measured area is queried and extracted from the measured thickness data according to the position information of the measured area.

[0544] In step S33103, the measured point thickness data corresponding to each machining point is determined based on the measured area thickness data corresponding to each measured area.

[0545] For example, the measured area thickness data corresponding to each measured area can be averaged, and the average value is determined as the measured point thickness data corresponding to the machining point in the measured area.

[0546] In the embodiment, by combining the position information, size information and process offset information corresponding to each processing point, the measured area corresponding to each processing point is demarcated, the measurement range can be accurately positioned, the actual influence range of processing is ensured to be completely covered by the measured area, and thickness data distortion caused by insufficient measurement area is avoided. On the other hand, by statistical analysis of the thickness values of multiple points in the measured area, the interference of local material non-uniformity or measurement noise can be effectively eliminated, and thickness data that can better reflect the actual processing condition is obtained.

[0547] It should be understood that, although each step in the flowchart involved in each of the above embodiments is displayed in sequence according to the arrow, these steps are not necessarily executed in the order indicated by the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other orders. Moreover, at least part of the steps in the flowchart involved in each of the above embodiments can include multiple steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily sequential, but can be alternately executed with at least part of other steps or steps or stages in other steps.

[0548] Based on the same inventive concept, the embodiments of the present application also provide a circuit board laser processing device for implementing the above-mentioned circuit board laser processing method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme described in the above method, so the specific limitations in one or more circuit board laser processing device embodiments provided below can refer to the limitations of the circuit board laser processing method in the foregoing, which will not be repeated here.

[0549] In one exemplary embodiment, as shown in FIG. 35, the present application provides a circuit board laser processing device, comprising a laser processing device 3504 and a controller 3502, wherein:

[0550] The laser processing device 3504 is configured to process the circuit board to be processed;

[0551] The controller 3502 is configured to:

[0552] Obtain measured thickness data, theoretical thickness data and theoretical process parameter values of the circuit board to be processed, wherein the measured thickness data is obtained by scanning the circuit board to be processed by a scanning device, and the theoretical process parameter values are determined based on the theoretical thickness data;

[0553] Adjust the theoretical process parameter values according to the deviation between the measured thickness data and the theoretical thickness data to obtain target process parameter values;

[0554] The laser processing device is controlled to process the circuit board to be processed according to the target process parameter value.

[0555] In an exemplary embodiment, the circuit board laser processing device further comprises a scanning device configured to scan the circuit board to be processed to obtain measured thickness data of the circuit board to be processed.

[0556] In an exemplary embodiment, the controller can also implement the steps in the above method embodiments.

[0557] In an exemplary embodiment, the present application provides a computer device, which can be a terminal, and its internal structure diagram can be as shown in FIG. 31. For the description of the computer device, reference can be made to the related content in the foregoing embodiments, which will not be described herein again.

[0558] Those skilled in the art can understand that the structure shown in FIG. 31 is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0559] In an embodiment, the present application further provides a computer device including a memory and a processor, the memory storing a computer program, and the processor implementing the steps in the above method embodiments when executing the computer program.

[0560] In an embodiment, the present application provides a computer readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the steps in the above method embodiments.

[0561] In an embodiment, the present application provides a computer program product including a computer program, the computer program being executed by a processor to implement the steps in the above method embodiments.

[0562] In an embodiment, a circuit board is also provided, which is processed by the above circuit board laser processing method.

[0563] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of the relevant data need to comply with relevant regulations.

[0564] Finally, it should be noted that in the description of the specification, specific features, structures, etc. can be combined in any one or more embodiments or examples in a suitable manner. Moreover, the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method of processing a wiring board, characterized by, The processing method comprises the following steps: The scanning device is used to scan the circuit board and obtain information of the circuit board, and the circuit board is processed according to the information of the circuit board.

2. The method of claim 1, wherein, The processing method comprises the following steps: The circuit board comprises a multilayer substrate, a through hole is formed in the multilayer substrate, and the through hole is subjected to electroplating treatment to obtain a multilayer substrate with a metal through hole; The scanning device comprises a CT scanning device, and the CT scanning device is used to perform CT scanning on the multilayer substrate to determine a back drilling depth of the metal through hole to be back drilled, and the metal through hole is subjected to back drilling drilling of a preset depth according to the back drilling depth, thereby obtaining a circuit board.

3. The method of claim 2, wherein, The CT scanning on the multilayer substrate comprises: Determine the area of the multilayer substrate to be processed back drilling, and perform CT scanning on the multilayer substrate at the corresponding position according to the area of the multilayer substrate to be processed back drilling.

4. The method of claim 2, wherein, The CT scanning on the multilayer substrate to determine the back drilling depth of the metal through hole to be back drilled, and the metal through hole is subjected to back drilling drilling of a preset depth according to the back drilling depth, comprises: Performing graphic processing on the surface of the top layer substrate of the multilayer substrate with the metal through hole to obtain a multilayer substrate with a surface circuit layer; Performing CT scanning on the multilayer substrate to determine the back drilling depth of the metal through hole to be back drilled at the corresponding position, and performing back drilling drilling of a preset depth from the corresponding metal through hole of the top layer substrate in the depth direction according to the back drilling depth.

5. The method according to any one of claims 2 to 4, characterized in that, The CT scanning on the multilayer substrate to determine the back drilling depth of the metal through hole to be back drilled, comprises: Performing CT scanning on the multilayer substrate to determine the reference layer position and the target layer position of the multilayer substrate, the reference layer position is the depth information of the top layer substrate, and the target layer position is the depth information of the target layer substrate which does not need to be connected by a circuit in the multilayer substrate; Calculating the vertical distance between the reference layer position and the target layer position to obtain the back drilling depth of the metal through hole from the top layer substrate to the target layer substrate.

6. The method of claim 5, wherein, The CT scanning on the multilayer substrate to determine the reference layer position and the target layer position of the multilayer substrate comprises: Taking at least three reference points on the upper surface of the top layer substrate arranged on the multilayer substrate, determining a reference surface according to the reference points, calculating the depth of the reference surface to obtain the reference layer position; Performing CT scanning on the multilayer substrate to generate three-dimensional position information of the target layer substrate of the multilayer substrate, extracting the depth information of N metal holes on the target layer substrate in the three-dimensional position information as N target layer positions, N≥1; Calculating the vertical distance between the reference layer position and the target layer position to obtain the back drilling depth of the metal through hole from the top layer substrate to the target layer substrate, specifically comprising: Calculating the vertical distance between the reference layer position and each target layer position to obtain N back drilling depths of the metal through hole from the top layer substrate to the target layer substrate.

7. The method of claim 2, wherein, After the CT scanning on the multilayer substrate to determine the back drilling depth of the metal through hole, the method further comprises: The two-dimensional code containing the back drilling depth is marked at the corner position of the multi-layer substrate; The two-dimensional code at the corner position of the multi-layer substrate is scanned by a drilling machine to obtain the back drilling depth, so that the drilling machine performs drilling processing according to the back drilling depth.

8. The method of claim 7, wherein, The two-dimensional code containing the back drilling depth is marked at the corner position of the multi-layer substrate, including: The two-dimensional code at the corner position of the multi-layer substrate is formed by laser marking equipment, or the two-dimensional code at the corner position of the multi-layer substrate is formed by graphic exposure processing, or the two-dimensional code at the corner position of the multi-layer substrate is formed by spraying processing using a CT scanning machine.

9. The method of claim 4, wherein, After the drilling processing is performed from the metal via hole on the top layer substrate in the depth direction according to the back drilling depth to obtain a multi-layer circuit board, the method further includes: Reference drilling data of the drilling processing is obtained, the reference drilling data and the actual drilling data obtained by detection are compared to obtain a deviation value between the reference drilling data and the actual drilling data, and drilling compensation processing is performed on the metal via hole causing the deviation value by using a drilling machine according to the deviation value; Or, reference drilling data corresponding to the drilling processing of N multi-layer substrates in the current batch is obtained, N≥1, N sets of reference drilling data and actual drilling data obtained by detection are compared to obtain deviation values between the N sets of reference drilling data and the actual drilling data, a comprehensive deviation value is determined according to the N deviation values, and drilling compensation processing is performed on the metal via hole of the multi-layer substrate in the current batch by using a drilling machine according to the comprehensive deviation value.

10. The method of claim 9, wherein, The back drilling depth is obtained by using a transmission mode of network communication of a drilling machine, and drilling processing is performed from the metal via hole on the top layer substrate in the depth direction according to the back drilling depth.

11. The method of claim 4, wherein, The surface of the top layer substrate on the multi-layer substrate with the metal via hole is subjected to graphic processing to obtain a multi-layer substrate with a surface circuit layer, including: The surface of the top layer substrate on the multi-layer substrate is cleaned, a dry film is attached to the surface of the top layer substrate, and the top layer substrate is subjected to exposure processing by using an exposure device and ultraviolet light; the top layer substrate is subjected to development processing to obtain a top layer substrate with pattern transfer; The top layer substrate is subjected to graphic electroplating processing, and the dry film is removed to obtain a multi-layer substrate with a surface circuit layer.

12. The method of claim 1, wherein, The method includes: The scanning device includes a computer layered imaging device, and the computer layered imaging device is used to scan and obtain depth information corresponding to the back drilling position of the circuit board, so as to control the back drilling depth of the corresponding back drilling position according to the depth information.

13. The method of claim 12, wherein, The scanning and obtaining of the depth information corresponding to the back drilling position of the circuit board by using the computer layered imaging device includes: The circuit board is scanned to obtain two-dimensional tomographic images of each layer inside the circuit board; A three-dimensional image of the circuit board is constructed according to the two-dimensional tomographic images; According to the three-dimensional image and the two-dimensional tomographic image, depth information corresponding to the back-drilling position of the circuit board is obtained, and the depth information includes coordinates of a target structure under the back-drilling position of the circuit board in a depth direction of the circuit board.

14. The method of claim 13, wherein, The method according to the three-dimensional image and the two-dimensional tomographic image, depth information corresponding to the back-drilling position of the circuit board is obtained, and the depth information includes coordinates of a target structure under the back-drilling position of the circuit board in a depth direction of the circuit board. The three-dimensional image of the circuit board is cut along the depth direction of the circuit board to obtain a longitudinal sectional view of the back-drilling position of the circuit board; According to the longitudinal sectional view of the back-drilling position and the two-dimensional tomographic image of different depths of the circuit board, a target two-dimensional tomographic image corresponding to the position of the target structure is determined; The coordinates of the target two-dimensional tomographic image in the depth direction of the circuit board are taken as the coordinates of the target structure in the depth direction of the circuit board.

15. The method of claim 13, wherein, The target structure includes an upper surface of a target layer and an upper surface of an upper surface layer; the target layer refers to the conductive layer closest to the back-drilling termination position, the upper surface layer refers to the first conductive layer drilled in back-drilling, and the upper surface refers to the surface of the conductive layer closest to the drilling surface of the circuit board back-drilled; the depth information includes the coordinates of the upper surface of the target layer in the depth direction of the circuit board and the coordinates of the upper surface of the upper surface layer in the depth direction of the circuit board, and the method further comprises: According to the depth information, the distance between the target layer and the upper surface layer at the back-drilling position is determined; According to the distance, the back-drilling controlled depth processing depth of the back-drilling position is determined.

16. The method of claim 13, wherein, The target structure includes a residual stub end and an upper surface of a target layer; the depth information includes the coordinates of the residual stub end in the depth direction of the circuit board and the coordinates of the upper surface of the target layer in the depth direction of the circuit board, and the method further comprises: According to the depth information, the length of the residual stub is calculated; It is judged whether the length of the residual stub is within a preset qualified length range, and if so, it is confirmed that the back-drilling controlled depth processing is qualified.

17. The method of claim 15, wherein, According to the distance, the back-drilling controlled depth processing depth of the back-drilling position is determined, comprising: After the copper plating process, the circuit board is scanned to obtain the two-dimensional tomographic image of each layer inside the circuit board, and the difference between the distance and the target residual stub length is taken as the back-drilling controlled depth processing depth; Before the copper plating process, the circuit board is scanned to obtain the two-dimensional tomographic image of each layer inside the circuit board, the sum of the distance and the copper plating thickness is calculated first, then the sum is subtracted by the target residual stub length, and the difference is taken as the back-drilling controlled depth processing depth.

18. The method of claim 12, wherein, The method comprises: After the through-hole drilling and electroplating processing of the circuit board are completed, the computer layered imaging equipment is used to scan and obtain the depth information corresponding to the back-drilling position of the circuit board.

19. The method of claim 1, wherein, The scanning device comprises a detection device, and based on the configured detection device and drilling processing equipment, the method comprises: Based on the circuit board with plated holes, actual position information of each plated hole to be back-drilled on the circuit board is acquired by the detection device to determine a hole position deviation value, and actual center coordinates of back-drilling are determined according to the hole position deviation value; And a back-drilling depth of the plated hole is determined; Based on the actual center coordinates and the back-drilling depth of each plated hole to be back-drilled, back-drilling is performed on the circuit board by the drilling device.

20. The method of claim 19, wherein, The detection device includes a detection device with thickness detection function, and the back-drilling depth of the plated hole is determined, specifically including: Actual thickness of a region corresponding to each plated hole to be back-drilled on the circuit board is measured by the detection device; According to the actual thickness, a ratio of a target layer design depth to be back-drilled to a design thickness of the circuit board is determined, and a back-drilling depth of each plated hole to be back-drilled is determined; Based on the actual center coordinates and the back-drilling depth of each plated hole to be back-drilled, back-drilling is performed on the circuit board by the drilling device, specifically including: Based on the actual center coordinates of each plated hole to be back-drilled, the drilling device reaches each predetermined position, and back-drilling is performed on the circuit board according to the back-drilling depth of the plated hole.

21. The method of claim 20, wherein, The detection device includes a non-destructive testing device, and the non-destructive testing device includes an X-ray detection device, and the back-drilling depth of the plated hole is determined, specifically including: A back-drilling depth of each plated hole to be back-drilled is acquired by the non-destructive testing device; After back-drilling of the circuit board is completed, the method further includes: Whether the back-drilling depth of the plated hole is within a target deviation value is detected by the non-destructive testing device, and if not, a difference value is fed back to the drilling device for compensation adjustment.

22. The method of claim 19, wherein, Based on the circuit board with plated holes, the following steps are taken: Drilling is performed at a predetermined position of the circuit board to obtain a through hole penetrating through the circuit board; Plating treatment is performed on the through hole to obtain the circuit board with plated holes.

23. The method of claim 19, wherein, Actual position information of each plated hole to be back-drilled on the circuit board is acquired by the detection device to determine a hole position deviation value, specifically including: Drilling positions of the plated holes corresponding to the back-drilling surface on the circuit board are detected by the detection device to obtain actual position information of the plated holes corresponding to the back-drilling surface; According to the actual position information and theoretical position information of the plated holes corresponding to the back-drilling surface, a corresponding hole position deviation value is determined.

24. The method of claim 20, wherein, The detection device with thickness detection function is a laser thickness measuring device, and actual thickness of a region corresponding to each plated hole to be back-drilled on the circuit board is measured by the laser thickness measuring device.

25. The method of any one of claims 22-24, wherein, The drilling device has a plurality of machining spindles, and the method further includes: Through drilling and back-drilling of the same circuit board are performed on the same machining spindle.

26. The method of claim 1, wherein, The method includes: The scanning device includes a stub detection device, and based on a preliminary back-drilling structure on the circuit board, the stub detection device is controlled to scan the preliminary back-drilling structure to obtain stub position information of a stub in the preliminary back-drilling structure; Based on the residual pin position information, control the laser to subtract the residual pin in the preliminary back drilling structure.

27. The method of claim 26, wherein, The preliminary back drilling structure on the circuit board is processed by the following steps: positioning the structure to be processed on the circuit board, controlling the preliminary back drilling processing device to back drill the structure to be processed to form a preliminary back drilling structure; the preliminary back drilling structure includes a back drilling hole, and the back drilling hole includes a conductive via hole segment and a back drilling segment; the spot size of the laser is smaller than the aperture of the back drilling segment and larger than the aperture of the conductive via hole segment.

28. The method of claim 26, wherein, The length of the residual pin after laser subtracting is less than or equal to the larger one of the detection accuracy value of the residual pin detection device and the processing accuracy value of the laser.

29. The method of claim 26, wherein, The length of the residual pin after laser subtracting is less than or equal to 20 μm.

30. The method of claim 26, wherein, The method comprises the following steps: Based on the residual pin position information and the structure information of the circuit board, determine the medium layer material information, conductive plating layer material information and conductive plating layer thickness information corresponding to the residual pin; According to the residual pin position information, the medium layer material information, the conductive plating layer material information and the conductive plating layer thickness information, set the laser processing parameters; Control the laser to subtract the residual pin in the preliminary back drilling structure according to the set laser processing parameters.

31. The method of claim 30, wherein, The laser processing parameters include laser power and laser pulse number.

32. The method of any one of claims 26 to 31, wherein, The residual pin detection device includes a computer tomography device or a computer layer imaging device.

33. The method of any one of claims 26 to 31, wherein, The laser includes an ultrafast laser.

34. The method of claim 1, wherein, The method comprises the following steps: Obtain the measured thickness data, the theoretical thickness data and the theoretical process parameter value of the circuit board, wherein the measured thickness data is obtained by scanning the circuit board by the scanning device, and the theoretical process parameter value is determined based on the theoretical thickness data; Adjust the theoretical process parameter value according to the deviation between the measured thickness data and the theoretical thickness data to obtain a target process parameter value; Control the laser processing device to process the circuit board according to the target process parameter value.

35. The method of claim 34, wherein, Obtaining the theoretical thickness data and the theoretical process parameter value of the circuit board comprises the following steps: Read the theoretical thickness data and the theoretical process parameter value of the circuit board from the data carrier on the circuit board.

36. The method of claim 35, wherein, The data carrier is used to store the information storage link corresponding to the circuit board; before the control laser processing device processes the circuit board according to the target process parameter value, the method further comprises the following steps: Write the target process parameter value into the information storage link corresponding to the circuit board; Read the information storage link from the data carrier on the circuit board, and obtain the target process parameter value by accessing the information storage link.

37. The method of claim 34, wherein, The circuit board is provided with a plurality of processing point positions, and the target process parameter value includes a target point position process parameter value corresponding to each processing point position; the measured thickness data includes a measured point position thickness data corresponding to each processing point position; The method comprises the following steps: extracting, from the measured thickness data, measured point thickness data corresponding to each processing point; adjusting the theoretical process parameter value according to the deviation between the measured point thickness data corresponding to each processing point and the theoretical thickness data, to obtain a target point process parameter value of each processing point; controlling the laser processing device to process the circuit board according to the target process parameter value, including: setting a laser processing device according to the target point process parameter value corresponding to each processing point; controlling the laser processing device to process at each processing point according to the target point process parameter value set for each processing point.

38. The method of claim 37, wherein, At least part of the target point process parameter values are the same; setting a laser processing device according to the target point process parameter value corresponding to each processing point includes: dividing each processing point into a plurality of to-be-processed groups based on the target point process parameter value of each processing point, and determining a current to-be-processed group from the to-be-processed groups, the target point process parameter values of each processing point belonging to the same to-be-processed group being the same; setting step: setting a laser processing device according to the target point process parameter value corresponding to the current to-be-processed group; controlling the laser processing device to process the processing points in the current to-be-processed group according to the target point process parameter value corresponding to the current to-be-processed group; after processing all processing points in the current to-be-processed group, re-determining the current to-be-processed group from the unprocessed to-be-processed groups, and returning to execute the setting step until all to-be-processed groups are processed. The theoretical process parameter value includes position information, size information, and process offset information corresponding to each processing point.

39. The method of claim 37, wherein, The measured thickness data includes measured area thickness data corresponding to each measured area. According to the position information, size information, and process offset information corresponding to each processing point, determine the measured area corresponding to each processing point; extracting, from the measured thickness data, measured point thickness data corresponding to each processing point; based on the measured area thickness data corresponding to each measured area, determine the measured point thickness data corresponding to each processing point. The scanning device includes a computer tomography device or a computer layer imaging device.

40. The method of any one of claims 34 to 39, wherein, The circuit board includes at least one layer of conductive material and at least one layer of insulating material; the theoretical thickness data includes the theoretical thickness value of each conductive material layer and the theoretical thickness value of each insulating material layer; the measured thickness data includes the measured thickness value of each conductive material layer and the measured thickness value of each insulating material layer.

41. The method of any one of claims 34 to 39, wherein, The circuit board is prepared by the processing method according to any one of claims 1 to 41.

42. A circuit board, characterized by The back drilling device is integrated with an X-RAY detection device, and is used for back drilling processing of the circuit board according to the processing method of any one of claims 1 to 11.

43. A back-drilling apparatus, comprising: The back drilling device is integrated with an X-RAY detection device, and is used for back drilling processing of the circuit board according to the processing method of any one of claims 1 to 11.

44. The back-drilling apparatus of claim 43, wherein, The back-drilling drilling equipment further comprises a controller, a data input end of the controller being connected with a data output end of the X-RAY detection equipment, for acquiring CT scanning data; and a data output end of the controller being connected with a data input end of the drilling machine, for outputting back-drilling depth.

45. A back-drilling system for a circuit board, comprising: The system comprises a computer layered imaging device; The computer layered imaging device is used for scanning and acquiring depth information corresponding to back-drilling positions of the circuit board, so as to perform back-drilling depth control processing on the corresponding back-drilling positions according to the depth information.

46. The back-drilling system of claim 45, wherein, The computer layered imaging device comprises a control system and a processing module; The control system is used for controlling the computer layered imaging device to scan the circuit board, so as to acquire two-dimensional tomographic images of each layer of the circuit board; The processing module is used for constructing a three-dimensional image of the circuit board according to the two-dimensional tomographic images, and acquiring depth information corresponding to back-drilling positions of the circuit board according to the three-dimensional image and the two-dimensional tomographic images, the depth information comprising coordinates of a target structure at the back-drilling positions of the circuit board in the depth direction of the circuit board.

47. The back-drilling system of claim 46, wherein, The acquisition of the depth information corresponding to the back-drilling positions of the circuit board according to the three-dimensional image and the two-dimensional tomographic images comprises: slicing the three-dimensional image of the circuit board in the depth direction of the circuit board to obtain a longitudinal sectional view of the back-drilling positions of the circuit board; determining a target two-dimensional tomographic image corresponding to the position of the target structure according to the longitudinal sectional view of the back-drilling positions and the two-dimensional tomographic images of different depths of the circuit board; taking the coordinates of the target two-dimensional tomographic image in the depth direction of the circuit board as the coordinates of the target structure in the depth direction of the circuit board.

48. The back-drilling system of claim 46 or 47, wherein, The target structure comprises at least one of the following: an upper surface of a single conductive layer and a stub end; wherein the upper surface refers to the surface of the conductive layer closest to the back-drilling into the drilling surface of the circuit board.

49. The back-drilling system of claim 47, wherein, Before controlling the computer layered imaging device to scan the circuit board, the control system is further used for: acquiring a back-drilling drill tape file of the circuit board, the back-drilling drill tape file comprising the back-drilling positions; controlling the computer layered imaging device to scan the circuit board comprises: performing scanning of different regions of the circuit board with different precisions according to the back-drilling positions in the back-drilling drill tape file of the circuit board, to obtain the two-dimensional tomographic images, the image precision of the back-drilling positions in the two-dimensional tomographic images being the highest.

50. The back-drilling system of claim 49, wherein, The back-drilling drill tape file further comprises a theoretical depth of a target layer, the target layer referring to the conductive layer closest to the back-drilling termination position, and the target structure comprising an upper surface of the target layer; determining a region in the longitudinal sectional view that needs to perform image segmentation according to the theoretical depth of the target layer, determining the conductive layer through image segmentation, and taking the conductive layer as the target layer; ​ The processing module is further configured to:

51. The back-drilling system of claim 46, wherein, The target structure includes an upper surface of a target layer and an upper surface of an upper surface layer, the upper surface layer refers to a first conductive layer drilled in back drilling, and the depth information includes a coordinate of the upper surface of the target layer in the depth direction of the circuit board and a coordinate of the upper surface of the upper surface layer in the depth direction of the circuit board. The processing module is further configured to: The processing module is further configured to:

52. The back-drilling system of claim 51, wherein, The system further includes a circuit board drilling device. The computer layered imaging device is configured to send the back drilling controlled depth processing depth determined by the processing module to the circuit board drilling device. The circuit board drilling device is configured to perform back drilling controlled depth processing at the back drilling position according to the back drilling controlled depth processing depth.

53. The back-drilling system of claim 46, wherein, The target structure includes a residual stub end and an upper surface of a target layer, and the depth information includes a coordinate of the residual stub end in the depth direction of the circuit board and a coordinate of the upper surface of the target layer in the depth direction of the circuit board. The processing module is further configured to: The processing module is further configured to:

54. The back-drilling system of claim 51, wherein, The processing module is further configured to: In a case where the circuit board is scanned after a copper plating process to obtain two-dimensional tomographic images of each layer inside the circuit board, the difference between the distance and the target residual stub length is taken as the back drilling controlled depth processing depth. In a case where the circuit board is scanned before a copper plating process to obtain two-dimensional tomographic images of each layer inside the circuit board, the sum of the distance and the copper plating thickness is calculated first, and then the sum is subtracted by the target residual stub length, and the difference is taken as the back drilling controlled depth processing depth.

55. The back-drilling system of claim 45, wherein, The scanning and obtaining of the depth information corresponding to the back drilling position of the circuit board include: After through hole drilling and electroplating processing of the circuit board are completed, the computer layered imaging device is used to scan and obtain the depth information corresponding to the back drilling position of the circuit board.

56. A back-drilling depth control processing device for circuit boards, characterized in that, The device is configured to scan and obtain the depth information corresponding to the back drilling position of the circuit board by using the computer layered imaging device, so as to perform back drilling controlled depth processing on the corresponding back drilling position according to the depth information.

57. A circuit board drilling system, comprising: The system includes the back drilling drilling system of the circuit board according to any one of claims 45-55, or the back drilling controlled depth processing device of the circuit board according to claim 56.

58. A back-drilling apparatus for a circuit board, characterized by comprising: The back drilling processing device includes a detection device and a drilling processing device, wherein: The detection device is configured to obtain actual position information of each corresponding electroplated hole to be back drilled on the circuit board based on the circuit board with the electroplated holes, to determine a hole position deviation value, to determine actual center coordinates of back drilling processing according to the hole position deviation value, and to determine a back drilling depth of the corresponding electroplated hole. The detection device is configured to obtain actual position information of each corresponding electroplated hole to be back drilled on the circuit board based on the circuit board with the electroplated holes, to determine a hole position deviation value, to determine actual center coordinates of back drilling processing according to the hole position deviation value, and to determine a back drilling depth of the corresponding electroplated hole. The drilling processing device is used for back drilling processing of the circuit board based on actual center coordinates and back drilling depth corresponding to each to-be-back-drilled processing electroplating hole.

59. The back drilling apparatus of claim 58, wherein, The detection device comprises a laser thickness measurement module and / or a hole site detection module.

60. A back-drilling system for a circuit board, comprising: The back drilling processing system comprises the drilling processing device and the detection device according to claim 58 or 59. The drilling processing device and the detection device are used for cooperative operation to realize the back drilling processing method according to any one of claims 18 to 24.

61. A back drilling apparatus characterized by, The back drilling processing device comprises: A laser processing device configured to subtract material from a stub in a preliminary back drilling structure on a circuit board based on stub position information, wherein the stub position information is obtained by scanning the preliminary back drilling structure by a stub detection device.

62. The back drilling apparatus of claim 61, wherein, The back drilling processing device further comprises: A stub detection device configured to detect stub position information of a stub in a preliminary back drilling structure on a circuit board by scanning the preliminary back drilling structure.

63. A back drilling apparatus characterized by, The back drilling processing device comprises: A stub detection device configured to detect stub position information of a stub in a preliminary back drilling structure on a circuit board by scanning the preliminary back drilling structure, wherein the stub position information is used to control the laser processing device to subtract material from the stub in the preliminary back drilling structure to reach a preset target value.

64. A circuit board laser processing apparatus, comprising: The circuit board laser processing device comprises a laser processing device and a controller, wherein: The laser processing device is configured to process a circuit board; The controller is configured to: Obtain measured thickness data, theoretical thickness data and theoretical process parameter values of the circuit board, wherein the measured thickness data is obtained by scanning a to-be-processed circuit board by a scanning device, and the theoretical process parameter values are determined based on the theoretical thickness data; Adjust the theoretical process parameter values according to a deviation between the measured thickness data and the theoretical thickness data to obtain target process parameter values; Control the laser processing device to process the circuit board according to the target process parameter values.

65. The apparatus of claim 64, wherein, The circuit board laser processing device further comprises a scanning device configured to scan a to-be-processed circuit board to obtain measured thickness data of the circuit board.

Images