A method for manufacturing a high-density multilayer circuit board
By setting multiple targets in high-density multilayer circuit boards and using specific alignment methods, combined with semi-additive or additive processes, the problems of insufficient alignment accuracy and long process flow of blind vias between layers are solved, achieving high-precision and low-cost circuit board manufacturing.
Patent Information
- Application Number
- CN202211100044.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-09-09
- Publication Date
- 2026-01-20
- Estimated Expiration
- 2042-09-09
AI Technical Summary
In existing high-density multilayer circuit board manufacturing methods, the alignment accuracy of blind vias between layers is insufficient and the process is relatively long. As the number of laminations increases, the alignment accuracy will become worse. Furthermore, common target designs are easily affected by processes such as electroplating, making it difficult to control the accuracy.
Multiple targets are set on the inner sub-board. Alignment points are captured by X-ray target ablation machine, laser ablation, or laser drilling machine with X-ray equipment and pattern exposure machine. Combined with semi-additive or additive processes, the influence of electroplating nodules is avoided, the process is simplified and the alignment accuracy is improved.
It improves the alignment accuracy of blind holes between layers, shortens the processing flow, avoids accuracy abnormalities caused by target deformation or electroplating nodules, is applicable to various machine tools, and reduces costs.
Smart Images
Figure CN115811833B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of PCB, and particularly relates to a manufacturing method of a high-density laminated circuit board. BACKGROUND
[0002] With the vigorous development and in-depth application of new technologies such as 5G+ABC+IoT, the printed circuit board for the purpose of carrying and connecting electronic components is evolving towards high density, high precision, high integration, small aperture, thin wires, small pitch, multi-layer, high speed, high frequency, high reliability, low cost, light weight and thin type. The high-density laminated circuit board emerges as the times require and can well meet the development trend of the industry.
[0003] The high-density laminated circuit board has the characteristics of high density, high precision and high integration, and therefore has a very high requirement on the alignment accuracy. The accuracy of the laminated circuit board generally includes three kinds of blind hole and blind hole, blind hole and outer adjacent layer pattern, and blind hole and inner adjacent layer pattern. The factors affecting the accuracy mainly include mechanical drilling accuracy (65 µm), laser blind hole accuracy (25 µm), X-ray drilling target accuracy (20 µm), and pattern transfer accuracy (20 µm). Different target designs and processing methods are affected by the above four factors in different types and times, and the alignment accuracy is also different. Generally, avoiding the influence of the factors with poor accuracy and reducing the influence times of each factor can effectively improve the alignment accuracy.
[0004] In the prior art, there are three commonly used target design and processing methods:
[0005] Scheme 1:
[0006] First step: making patterns and first targets on the inner layer core board, performing first laminated pressing to form a first outer layer sub-board, and then using an X-ray targeting machine to drill the first targets to form first alignment holes;
[0007] Second step: using the first alignment holes for alignment, using pattern transfer to make blind hole windowing and second targets on the outer layer sub-board. Then using the X-ray targeting machine to drill the second targets to form second alignment holes;
[0008] Third step: using the second alignment holes for alignment, making laser drilling to form blind holes, and then performing hole metallization.
[0009] Fourth step: using the first alignment holes for alignment again, making the first outer layer sub-board patterns and third targets by pattern transfer. Performing second laminated pressing to form a second outer layer sub-board, and then using the X-ray targeting machine to drill the third targets to form third alignment holes;
[0010] Fifth step: repeating the second to fourth steps until the outer layer patterns are made;
[0011] Sixth step: making subsequent processes as usual.
[0012] The factors affecting the alignment accuracy of scheme 1 are as follows: ① upper and lower blind holes: 2 times of laser blind hole accuracy + 2 times of X-ray drilling target accuracy + 2 times of pattern transfer accuracy; ② assuming that N times of lamination is performed, the blind hole of the first sub-plate and the outer blind hole: 2 times of laser blind hole accuracy + (N+1) times of X-ray drilling target accuracy + (N+1) times of pattern transfer accuracy; ③ blind hole and outer adjacent layer pattern: 1 time of laser blind hole accuracy + 1 time of X-ray drilling target accuracy + 2 times of pattern transfer accuracy; ④ blind hole and inner adjacent layer pattern: 1 time of laser blind hole accuracy + 1 time of X-ray drilling target accuracy + 2 times of pattern transfer accuracy.
[0013] Scheme 1 is suitable for first and second order HDI boards, and with the increase of the number of lamination, the alignment accuracy will be worse. The additional pattern transfer and drilling process in the second step not only affects the alignment accuracy, but also increases the cost.
[0014] Scheme 2:
[0015] First step: make patterns and first target on the inner core board, perform the first lamination to form the first outer sub-plate, and then use the X-ray drilling machine to drill the first target to form the first alignment hole;
[0016] Second step: reduce the copper on the surface of the first sub-plate to 6-10um by brown oxidation, use the first alignment hole to align and perform laser drilling with the direct copper process, and ablate the second alignment target. Then perform hole metallization;
[0017] Third step: use the second alignment hole target to align, transfer patterns to make the first outer sub-plate patterns and the third target. Perform the second lamination to form the second outer sub-plate, and then use the X-ray drilling machine to drill the third target to form the third alignment hole;
[0018] Fourth step: repeat the second to third steps until the outer layer patterns are made;
[0019] Fifth step: perform the subsequent process normally.
[0020] The factors affecting the alignment accuracy of scheme 2 are as follows: ① upper and lower blind holes: 2 times of laser blind hole accuracy + 1 time of X-ray drilling target accuracy + 1 time of pattern transfer accuracy; ② assuming that N times of lamination is performed, the blind hole of the first sub-plate and the outer blind hole: (N+1) times of laser blind hole accuracy + N times of X-ray drilling target accuracy + N times of pattern transfer accuracy; ③ blind hole and outer adjacent layer pattern: 1 time of laser blind hole accuracy + 1 time of pattern transfer accuracy; ④ blind hole and inner adjacent layer pattern: 1 time of laser blind hole accuracy + 1 time of X-ray drilling target accuracy + 1 time of pattern transfer accuracy.
[0021] Scheme 2 is the same as scheme 1, which is suitable for first and second order HDI board, and the positioning accuracy will be worse with the increase of the number of laminated. But it cancels the blind hole windowing process, which saves the cost compared with scheme 1.
[0022] Scheme 3:
[0023] First step: make patterns and first group of targets and blind hole targets on the inner core board, perform the first laminated to form the first outer layer sub-board, and then use the X-ray targeting machine to drill the first target in the first group of targets to form the first positioning hole;
[0024] Second step: brown the first sub-board to reduce the copper on the surface to 6-10um. Use the first positioning hole for positioning, ablate the blind hole target position to expose the blind hole target, and then use the blind hole target for positioning to perform laser drilling. Then perform hole metallization;
[0025] Third step: use the first positioning hole target for positioning, and make the first outer layer sub-board pattern by pattern transfer. Perform the second laminated to form the second outer layer sub-board, and then use the X-ray targeting machine to drill the second target in the first group of targets to form the second positioning hole;
[0026] Fourth step: repeat the second to third steps until the outer layer pattern is made;
[0027] Fifth step: make the subsequent process normally.
[0028] The factors affecting the positioning accuracy of scheme 3 are as follows: ① up and down blind holes: 2 times laser blind hole accuracy; ② assuming N times laminated, first sub-board blind hole and outer layer blind hole: 2 times laser blind hole accuracy; ③ blind hole and outer adjacent layer pattern: 1 time laser blind hole accuracy + 1 time X-ray drilling target accuracy + 1 time pattern transfer accuracy; ④ blind hole and inner adjacent layer pattern: 1 time laser blind hole accuracy + 1 time X-ray drilling target accuracy + 1 time pattern transfer accuracy.
[0029] Compared with scheme 2, scheme 3 has obvious improvement in theoretical positioning accuracy, and the positioning accuracy will not become worse with the increase of the number of laminated. However, in actual operation, the parameters for ablation of blind hole target need to be controlled carefully, otherwise it is easy to damage the blind hole target and cause accuracy disorder. During the laminated process, the blind hole target is subjected to hole metallization many times, and the plating nodules or residual chemicals can also cause target deformation, which affects the positioning accuracy of the target. In order to expose the blind hole target, scheme 3 increases the ablation process, which increases the cost. The blind hole target is below the surface of the board, and it is relatively difficult for the machine to grab the blind hole target, and even some machines need to be modified to grab the blind hole target.
[0030] In summary, the common target design scheme will become worse with the increase of the number of laminated. Even the common ablation target scheme will be affected by the plating process, and the accuracy is difficult to control.
[0031] In the prior art, the high-density multi-layer circuit board processing method comprises:
[0032] Scheme one: cutting → machine drilling buried holes and tool holes → hole metallization → making inner layer core plate patterns and a set of targets → pressing outer layer sub-boards → X-ray drilling image alignment holes → outer layer sub-boards making blind hole windowing → X-ray drilling blind hole alignment holes → laser blind hole processing → hole metallization → making outer layer sub-board patterns and targets → pressing outer layer sub-boards...... repeating the above process to make outer layer patterns → normal making.
[0033] However, the process uses different targets for blind holes and patterns of different layers, and the interlayer blind hole alignment accuracy is insufficient, and the process is relatively long.
[0034] Scheme two: cutting → machine drilling buried holes and tool holes → hole metallization → making inner layer core plate patterns and a set of targets → pressing outer layer sub-boards → X-ray drilling blind hole alignment holes → brown copper reduction 6-10 um → laser blind hole processing → hole metallization → making outer layer sub-board patterns and targets → pressing outer layer sub-boards...... repeating the above process to make outer layer patterns → normal making.
[0035] However, the process uses different targets for blind holes and patterns of different layers, and the interlayer blind hole alignment accuracy is insufficient.
[0036] Scheme three: cutting → machine drilling buried holes and tool holes → hole metallization → making inner layer core plate patterns and a set of blind hole targets → pressing outer layer sub-boards → X-ray drilling pattern alignment holes → outer layer sub-board blind hole target windowing → brown copper reduction 6-10 um → laser ablation inner layer blind hole target → laser blind hole processing → hole metallization → making outer layer sub-board patterns → pressing outer layer sub-boards...... repeating the above process to make outer layer patterns → normal making.
[0037] However, the process increases the outer layer sub-board blind hole target windowing process, and the process is relatively long. SUMMARY
[0038] Therefore, the present application provides a high-density multi-layer circuit board manufacturing method. Compared with the prior art high-density multi-layer circuit board manufacturing method, the present application can effectively improve the interlayer blind hole alignment accuracy and shorten the processing flow.
[0039] The technical scheme of the present application is as follows:
[0040] A high-density multi-layer circuit board manufacturing method, characterized in that it comprises the following steps:
[0041] S1. The inner layer sub-plate is provided with targets; the number of targets is the same as the number of lamination times, and the number of lamination times is N, and each group of targets is N, and the targets are respectively provided with numbers 1, 2, … N; taking a prior art ten-layer plate as an example, the number of lamination times is 4, and then four targets are provided in each group, and the numbers on the targets are 1, 2, 3 and 4 respectively. In particular, the targets of the present application can be designed according to actual needs.
[0042] S2. The target is made; the target can be made in three ways: 1. X-ray target machine targets the target hole of the inner layer sub-plate to form the target; 2. Laser ablation of the inner layer sub-plate target to make the target; 3. Laser drilling machine and graphic exposure machine are equipped with X-ray to identify the inner layer sub-plate target to make the target;
[0043] S3. Laser drilling; the outer layer sub-plate copper surface is browned on the brown line, and the direct copper process is used for laser drilling; S4. Hole metallization and pattern transfer.
[0044] Further, in step S2, the inner layer sub-plate forms a first outer layer sub-plate after the first lamination, and the target with the number “1” of the inner layer sub-plate is made to form the first alignment target; by analogy, the Nth lamination forms the Nth outer layer sub-plate, and the target with the number “N” of the inner layer sub-plate is made to form the Nth alignment target.
[0045] In the present application, the grabbing mode of the alignment hole point position includes one of the following:
[0046] Mode A. Target hole alignment: the X-ray target machine drills a target hole corresponding to the inner layer sub-plate target, and the laser drilling machine and the graphic exposure machine grab the target hole as the alignment point.
[0047] Mode B. Ablation target alignment: the corresponding inner layer sub-plate target is exposed by laser ablation, and the laser drilling machine and the graphic exposure machine grab the target as the alignment point;
[0048] Mode C. Directly grab the target alignment by adding X-ray: the laser drilling machine and the graphic exposure machine are modified, and X-ray equipment is added to the laser drilling machine and the graphic exposure machine, so that the laser drilling machine and the graphic exposure machine can directly grab the corresponding inner layer sub-plate target for alignment.
[0049] Further, in step S3, the copper surface of the first outer layer sub-plate is browned on the brown line, and the direct copper process is used for laser drilling, and the alignment target uses the first alignment target, and similarly, the laser drilling of the Nth outer layer sub-plate uses the Nth alignment target.
[0050] Further, in step S3, the laser drilling data sets up a positioning alignment hole at the alignment hole position, which is used for hole grabbing alignment during machine operation.
[0051] Further, the diameter of the positioning alignment hole is 2-4 mm.
[0052] Further, in step S4, the outer layer sub-plate and the outer layer hole metallization and pattern process of the alignment target manufacturing method 1 and 2 preferentially use the semi-additive method or additive method for preparation, and the outer layer sub-plate and the outer layer hole metallization and pattern process of the alignment target manufacturing method 3 are not limited. In the present application, the semi-additive method or additive method process is used for electroplating, and after the pattern exposure, the target hole drilled by X-ray and the target shape exposed by laser ablation are not affected by electroplating and electroplating nodules, thereby avoiding the precision abnormalities caused thereby. The alignment grabbing method of adding X-ray direct grabbing target alignment is not affected by the hole metallization and pattern transfer process image.
[0053] Further, the semi-additive method or additive method preparation includes the following steps: copper deposition - film pressing - exposure - development - electroplating - film removal - copper removal.
[0054] Further, in the exposure process, the first alignment target is used as the alignment target for the first outer layer sub-plate pattern exposure, and so on, the Nth alignment target is used as the alignment target for the Nth outer layer sub-plate pattern exposure.
[0055] Further, in addition to the inner layer sub-plate pattern exposure, the target group area corresponding to the area of all other levels of target group area, the pattern data is all equal to the copper area.
[0056] Further, on all outer layer sub-plate pattern data, the alignment target position is provided with a target, which is used for pattern exposure alignment.
[0057] Further, the diameter of the target hole is 2-4mm.
[0058] The present application also provides a processing method of a high-density laminated circuit board, characterized by comprising the following steps:
[0059] A. Inner layer sub-plate manufacturing; specifically: cutting core plate / conventional manufacturing of multi-layer board - machine drilling and tool hole - hole metallization - inner layer sub-plate pattern and target setting;
[0060] B. Outer layer sub-plate manufacturing; including the manufacturing method described above;
[0061] C. Outer layer pattern post-process manufacturing; those skilled in the art can prepare it by using the existing technology.
[0062] Through a large number of creative experiments of the present application, on the basis of the existing technology, it is found that different alignment point grabbing methods have different influence factors on precision, which are as follows:
[0063] 1. The factors affecting the accuracy of the drilling hole alignment of the X-ray drilling machine are as follows: upper and lower blind holes: twice laser blind hole accuracy + twice X-ray drilling accuracy; assuming that N times of laminated pressing are performed, the first sub-plate blind hole and the outer layer blind hole: twice laser blind hole accuracy + twice X-ray drilling accuracy; blind hole and outer adjacent layer pattern: once laser blind hole accuracy + once pattern transfer accuracy; blind hole and inner adjacent layer pattern: once laser blind hole accuracy + twice X-ray drilling accuracy + once pattern transfer accuracy.
[0064] 2. The factors affecting the accuracy of the ablation target alignment are as follows: upper and lower blind holes: twice laser blind hole accuracy; assuming that N times of laminated pressing are performed, the first sub-plate blind hole and the outer layer blind hole: twice laser blind hole accuracy; blind hole and outer adjacent layer pattern: once laser blind hole accuracy + once pattern transfer accuracy; blind hole and inner adjacent layer pattern: once laser blind hole accuracy + once pattern transfer accuracy.
[0065] 3. The factors affecting the accuracy of the X-ray direct grabbing target alignment are as follows: upper and lower blind holes: twice laser blind hole accuracy; assuming that N times of laminated pressing are performed, the first sub-plate blind hole and the outer layer blind hole: twice laser blind hole accuracy; blind hole and outer adjacent layer pattern: once laser blind hole accuracy + once pattern transfer accuracy; blind hole and inner adjacent layer pattern: once laser blind hole accuracy + once pattern transfer accuracy.
[0066] Compared with the prior art scheme 2, the theoretical alignment accuracy of the technical scheme of the present application is obviously improved, and the alignment accuracy does not become worse with the increase of the number of laminated pressing, and no additional process is added. Compared with the prior art scheme 3, the theoretical alignment accuracy of the present application has advantages and disadvantages. However, the present application saves the process of ablation blind hole target, avoids the risk of affecting the alignment accuracy caused by ablation damage to the target, and adopts the MSAP or SAP process, exposes the pattern and then electroplates, thereby avoiding the change of the hole shape caused by electroplating nodulation and affecting the exposure alignment accuracy. Based on the prior art, the inventor has made a large amount of creative labor, so that the technical scheme of the present application can obtain unexpected technical effects compared with the prior art.
[0067] In addition, the technical scheme of the present application adopts a target hole, so that there is no problem of abnormal quality caused by residual medicine, and the laser drilling and exposure are easy to identify, so that the present application can match all common machines and has a wide application range.
[0068] In the present application, the inner layer sub-plate refers to a core plate or a multi-layer plate before the first laminated pressing; the outer layer sub-plate refers to a pressed plate after the laminated pressing; and the outer layer plate refers to a pressed plate before the outer layer pattern is made.
[0069] The present application has the following beneficial effects:
[0070] 1. All outer layer sub-board alignment targets are derived from inner layer sub-boards. Patterns and laser drilling at the same level use the same target, avoiding the accuracy abnormalities caused by the change of alignment targets in conventional high-density multilayer circuit board manufacturing methods. The alignment accuracy is superior to traditional methods.
[0071] 2. Two alignment and gripping methods are used: drilling target holes for alignment and ablation for target alignment. The outer sub-board is manufactured using MSAP or SAP processes to avoid copper plating and electroplating nodules altering the target hole shape and thus affecting alignment accuracy. An X-ray direct target gripping method is added for alignment. After lamination, the target remains inside the board and is unaffected by the manufacturing process, resulting in higher alignment accuracy.
[0072] 3. Compared with conventional high-density multilayer circuit board manufacturing methods, different target grasping methods reduce processes such as blind hole opening. Among them, the target grasping method with X-ray direct target grasping and alignment further reduces processes such as X-ray target drilling machine drilling and laser ablation of the target, reducing manufacturing time and cost. Attached Figure Description
[0073] Figure 1 This is a process flow diagram of the high-density multilayer circuit board processing method of the present invention. Implementation
[0074] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0075] Example 1
[0076] A method for manufacturing a high-density multilayer circuit board, characterized by comprising the following steps:
[0077] S1. Targets are set on the inner sub-board; the number of targets is the same as the number of integration layers, the number of integration layers is N, the number of targets in each group is N, and the targets are respectively set with the numbers 1, 2, ... N;
[0078] S2. Target firing with an X-ray machine: After the inner sub-board is laminated to form the outer sub-board, the target is fired with an X-ray machine to form alignment holes;
[0079] S3. Laser drilling; Browning the outer layer copper surface of the sub-board by running a browning line and using direct copper drilling process for laser drilling; S4. Hole metallization and pattern transfer.
[0080] Further, in step S2, the inner layer sub-plate forms a first outer layer sub-plate after the first lamination, and the X-ray target machine is used to form a first alignment hole with a target number of "1"; similarly, the Nth outer layer sub-plate forms an Nth outer layer sub-plate after the Nth lamination, and the X-ray target machine is used to form an Nth alignment hole with a target number of "N".
[0081] Further, in step S3, the first outer layer sub-plate is browned along the brown line, and the direct copper process is used for laser drilling. The first alignment hole is used for the alignment hole, and the Nth outer layer sub-plate is drilled using the Nth alignment hole.
[0082] Further, in step S3, the laser drilling data is set in the alignment hole position to establish a positioning alignment hole for hole grabbing during machine operation.
[0083] Further, the diameter of the positioning alignment hole is 3.2 mm.
[0084] Further, in step S4, the outer layer sub-plate and the outer layer hole are metallized and patterned using the semi-additive process (MSAP).
[0085] Further, the semi-additive process includes the following steps: copper deposition, film pressing, exposure, development, electroplating, film removal, and copper removal.
[0086] Further, in the exposure process, the first alignment hole is used as the alignment hole for the first outer layer sub-plate pattern exposure, and the Nth alignment hole is used as the alignment hole for the Nth outer layer sub-plate pattern exposure.
[0087] Further, in addition to the pattern exposure of the inner layer sub-plate, the target group area corresponding area of all other levels is fully coppered to become a copper-free area.
[0088] Further, a target hole is set at the alignment hole position of the pattern data of all outer layer sub-plates for pattern exposure alignment.
[0089] Further, the diameter of the target hole is 3.2 mm.
[0090] Embodiment 2
[0091] A method for manufacturing a high-density laminated circuit board, characterized by comprising the following steps:
[0092] S1. The inner layer sub-plate is provided with targets; the number of targets is the same as the number of laminations, and the number of laminations is N. Each group of targets has N targets, and the targets are respectively provided with numbers 1, 2,..., and N.
[0093] S2. The target machine is used to shoot targets; the inner layer sub-plate forms an outer layer sub-plate after lamination, and the X-ray target machine is used to form an alignment hole with a target number.
[0094] S3. Laser drilling; brown the outer layer of the copper surface of the sub-plate, and use direct copper technology to perform laser drilling; S4. Hole metallization and pattern transfer.
[0095] Further, in step S2, after the first lamination of the inner layer sub-plate, a first outer layer sub-plate is formed, and an X-ray target machine is used to form a first alignment hole with a target of "1"; similarly, the Nth lamination forms an Nth outer layer sub-plate, and an X-ray target machine is used to form an Nth alignment hole with a target of "N".
[0096] Further, in step S3, the copper surface of the first outer layer sub-plate is browned along the brown line, and direct copper technology is used to perform laser drilling. The alignment hole uses the first alignment hole, and similarly, the Nth outer layer sub-plate laser drilling alignment hole uses the Nth alignment hole.
[0097] Further, in step S3, a positioning alignment hole is set at the position of the laser drilling data in the alignment hole for hole positioning during machine operation.
[0098] Further, the diameter of the positioning alignment hole is 2.5mm.
[0099] Further, in step S4, the outer layer sub-plate and the outer layer hole metallization and pattern technology use a semi-additive method for preparation.
[0100] Further, the semi-additive method for preparation includes the following steps: copper deposition - film pressing - exposure - development - electroplating - film removal - copper removal.
[0101] Further, in the exposure process, the first outer layer sub-plate pattern exposure uses the first alignment hole as the alignment hole, and similarly, the Nth outer layer sub-plate pattern exposure uses the Nth alignment hole as the alignment hole.
[0102] Further, in addition to the pattern exposure of the inner layer sub-plate, the target group area corresponding area of all other levels is fully equal to the copper area to become a copper-free area.
[0103] Further, on the pattern data of all outer layer sub-plates, a target hole is set at the position of the alignment hole for pattern exposure alignment.
[0104] Further, the diameter of the target hole is 2.5mm.
[0105] Example 3
[0106] A method for manufacturing a high-density laminated circuit board, characterized in that it comprises the following steps:
[0107] S1. Set targets on the inner layer sub-plate; the number of targets is the same as the number of laminations, and the number of laminations is N. Each group of targets has N targets, and the targets are respectively marked with numbers 1, 2,..., N.
[0108] S2. Targeting with a targeting machine; after the inner layer sub-plate is laminated, the outer layer sub-plate is formed, and a positioning hole is formed by using an X-ray targeting machine to target a target marked with a number;
[0109] S3. Laser drilling; the copper surface of the outer layer sub-plate is browned along a brown line, and laser drilling is performed by using a direct copper process; S4. Hole metallization and pattern transfer.
[0110] Further, in step S2, after the inner layer sub-plate is laminated for the first time, a first outer layer sub-plate is formed, and a first positioning hole is formed by using an X-ray targeting machine to target a target marked with a number “1”; by analogy, after the inner layer sub-plate is laminated for the Nth time, an Nth outer layer sub-plate is formed, and an Nth positioning hole is formed by using an X-ray targeting machine to target a target marked with a number “N”.
[0111] Further, in step S3, the copper surface of the first outer layer sub-plate is browned along a brown line, and laser drilling is performed by using a direct copper process; by analogy, the copper surface of the Nth outer layer sub-plate is browned along a brown line, and laser drilling is performed by using a direct copper process.
[0112] Further, in step S3, a positioning hole is set at the position of the laser drilling data in the positioning hole, which is used for hole positioning during machine operation.
[0113] Further, the diameter of the positioning hole is 3.6 mm.
[0114] Further, in step S4, the hole metallization and pattern process of the outer layer sub-plate and the outer layer are prepared by using an additive method (SAP).
[0115] Further, the additive method preparation includes the following steps: copper deposition, film pressing, exposure, development, electroplating, film removal, and copper removal.
[0116] Further, in the exposure process, the first outer layer sub-plate pattern exposure uses the first positioning hole as the positioning hole, and by analogy, the Nth outer layer sub-plate pattern exposure uses the Nth positioning hole as the positioning hole.
[0117] Further, in addition to the pattern exposure of the inner layer sub-plate, the target group area corresponding to the area of all other levels is fully equal to the copper area to become a copper-free area.
[0118] Further, a target hole is set at the position of the positioning hole on the pattern data of all outer layer sub-plates, which is used for pattern exposure positioning.
[0119] Further, the diameter of the target hole is 3.6 mm.
[0120] Example 4
[0121] A manufacturing method of a high-density laminated circuit board, characterized by comprising the following steps:
[0122] Step one: inner layer sub-plate and pattern target making;
[0123] A group of pattern targets are arranged at each corner of the inner layer sub-plate, and the target diameter is 3.2 mm. The target number is the same as the lamination number, and the lamination number is N. Each group of targets has N targets, and the targets are respectively marked with numbers 1, 2, …, N. Taking a ten-layer plate as an example, the lamination number is 4, and four targets are arranged in each group, and the targets are marked with numbers 1, 2, 3, and 4.
[0124] Step two: X-ray target hole punching;
[0125] The target hole is punched on the corresponding inner layer sub-plate target by the X-ray target machine, and the laser drilling machine and the pattern exposure machine grab the target hole as the alignment point. The first outer layer sub-plate after the first lamination is aligned with the inner layer sub-plate target marked with the number “1”, and the Nth outer layer sub-plate after the Nth lamination is aligned with the inner layer sub-plate target marked with the number “N”.
[0126] Step three: brown copper surface;
[0127] After the target hole is punched, the plate is browned on the brown line to facilitate the laser drilling machine to break through the surface copper layer.
[0128] Step four: laser drilling;
[0129] The laser drilling is performed by using the direct copper process, and the target hole generated in step two is used as the alignment point. A hole with a diameter of 3.2 mm is set at the corresponding inner layer sub-plate alignment target position to facilitate the machine operation to grab the alignment point.
[0130] Step five: hole metallization and pattern transfer;
[0131] ① Preferably, MSAP or SAP process flow is used for manufacturing;
[0132] ② Pattern exposure method:
[0133] The pattern exposure uses the target hole generated in step two as the alignment point. The area where the corresponding inner layer sub-plate target group is located is all equal to the copper area to become a copper-free area. At the same time, a circular pattern target with a diameter of 3.2 mm is set at the corresponding inner layer sub-plate alignment target position to facilitate the machine operation to grab the alignment point.
[0134] Example 5
[0135] A method for manufacturing a high-density laminated circuit board, characterized in that it comprises the following steps:
[0136] Step one: inner layer sub-plate and pattern target making;
[0137] A group of pattern targets are arranged at each corner of the inner layer sub-plate, and the target diameter is 3.2 mm. The number of targets is the same as the number of lamination times, and the number of lamination times is N. Each group of targets has N targets, and the targets are respectively marked with numbers 1, 2,..., N. Taking a ten-layer plate as an example, the number of lamination times is 4, and four targets are arranged in each group, and the numbers on the targets are respectively 1, 2, 3, and 4.
[0138] Step two: X-ray target machine punches a normal target hole;
[0139] The X-ray target machine is used to punch a normal target hole, which is used for alignment when laser ablation target is performed. The normal target hole is a milling edge positioning hole after pressing, and no special description is made here.
[0140] Step three: brown copper surface;
[0141] After the target hole is punched, the plate is browned on the copper surface on the brown line, so as to facilitate the laser drilling machine to break through the surface copper layer.
[0142] Step four: ablation of target;
[0143] The laser drilling machine is used to perform laser ablation by direct copper punching process, and the copper surface and the medium layer are ablated to expose the target of the inner layer sub-plate with a digital identifier. The laser drilling machine and the pattern exposure machine capture the target hole as an alignment point. The first outer layer sub-plate after the first lamination pressing uses the target of the inner layer sub-plate with a digital identifier of "1" as an alignment point, and the Nth outer layer sub-plate after the Nth lamination pressing selects the target of the inner layer sub-plate with a digital identifier of "N" as an alignment point.
[0144] Step five: laser drilling;
[0145] The laser drilling is performed by direct copper punching process, and the target hole generated in step four is used as an alignment point. A hole with a diameter of 3.2 mm is set at the position of the corresponding inner layer sub-plate alignment target to facilitate the machine to capture the alignment point.
[0146] Step six: hole metallization and pattern transfer
[0147] 1. Preferably, MSAP or SAP process flow is used for manufacturing;
[0148] 2. Pattern exposure method:
[0149] The pattern exposure uses the target hole generated in step four as an alignment point. The area where the target group of the corresponding inner layer sub-plate target is located is all equal to the copper area, which becomes a copper-free area. At the same time, a circular pattern target with a diameter of 3.2 mm is set at the position of the corresponding inner layer sub-plate alignment target to facilitate the machine to capture the alignment point.
[0150] Example 6
[0151] A manufacturing method of a high-density laminated circuit board, characterized in that it comprises the following steps:
[0152] Step one: inner layer sub-board and pattern target manufacturing;
[0153] A group of pattern targets are arranged at each corner of the inner layer sub-board, and the diameter of the target is 3.2 mm. The number of targets is the same as the number of lamination times, and the number of lamination times is N. Each group of targets has N targets, and the targets are respectively marked with numbers 1, 2,..., N. Taking a ten-layer board as an example, the number of lamination times is 4, and each group of targets has 4 targets, and the targets are respectively marked with numbers 1, 2, 3, and 4.
[0154] Step two: brown copper surface;
[0155] After the target hole is punched, the board is sent to the brown line to brown the copper surface, so as to facilitate the laser drilling machine to break through the surface copper layer.
[0156] Step three: laser drilling;
[0157] Direct copper technology is used for laser drilling. An X-ray device is installed on the laser drilling machine, which can read the position of the target at the four corners of the inner layer sub-board as a positioning point. The target marked with the number "1" on the first outer layer sub-board after the first lamination is used as the positioning point, and the target marked with the number "N" on the Nth outer layer sub-board after the Nth lamination is used as the positioning point. A hole with a diameter of 3.2 mm is set up at the corresponding positioning target position of the inner layer sub-board to facilitate the machine to grab the positioning point.
[0158] Step four: hole metallization and pattern transfer;
[0159] ① The subtractive process flow, MSAP or SAP process flow can be used for manufacturing.
[0160] ② Pattern exposure method:
[0161] An X-ray device is installed on the pattern exposure machine, which can read the position of the target at the four corners of the inner layer sub-board as a positioning point. The target marked with the number "1" on the first outer layer sub-board after the first lamination is used as the positioning point, and the target marked with the number "N" on the Nth outer layer sub-board after the Nth lamination is used as the positioning point. At the same time, a circular pattern target with a diameter of 3.2 mm is set up at the corresponding positioning target position of the inner layer sub-board to facilitate the machine to grab the positioning point.
[0162] Example 7
[0163] A manufacturing method of a high-density laminated circuit board, characterized in that it comprises the following steps:
[0164] A. Inner layer sub-board fabrication; specifically: cutting core board / conventional multilayer board fabrication—machine drilling and tooling holes—hole metallization—inner layer sub-board graphic design and target setting;
[0165] B. Fabrication of the outer sub-board; including the fabrication method of any one of Examples 1-3;
[0166] C. Production of the outer layer graphics.
[0167] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0168] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. It should be noted that any technical features not described in detail in this invention can be implemented using any existing technology.
Claims
1. A method of manufacturing a high-density build-up circuit board, characterized by, The method comprises the following steps: S1. The inner layer sub-plate is provided with targets; the number of targets is the same as the number of lamination times, and the number of targets in each group is N, and the targets are respectively provided with numbers 1, 2,..., N; S2. The alignment target is made; the alignment target can be made in three ways:
1. The X-ray target machine is used to make the target hole of the inner layer sub-plate target to form the alignment target; 2. The inner layer sub-plate target is ablated by laser to form the alignment target; 3. The laser drilling machine and the graphic exposure machine are provided with X-ray to identify the inner layer sub-plate target to form the alignment target; after the first lamination and pressing, the first outer layer sub-plate is formed, the target with the number "1" of the inner layer sub-plate is made to form the first alignment target; in this way, the target with the number "N" of the inner layer sub-plate is made to form the Nth alignment target after the Nth lamination and pressing to form the Nth outer layer sub-plate; S3. Laser drilling; the copper surface of the outer layer sub-plate is browned in the brown line, and the direct copper process is used for laser drilling; S4. Hole metallization and pattern transfer; the hole metallization and pattern process of the outer layer sub-plate and the outer layer using the first and second alignment target making methods uses the semi-additive method or the additive method, and the hole metallization and pattern process of the outer layer sub-plate and the outer layer using the third alignment target making method is not limited; The semi-additive method or the additive method comprises the following steps: copper deposition, film pressing, exposure, development, electroplating, film removal and copper removal.
2. The method of manufacturing a high-density build-up circuit board according to claim 1, wherein In step S3, the copper surface of the first outer layer sub-plate is browned in the brown line, and the direct copper process is used for laser drilling, and the alignment target uses the first alignment target, and the Nth outer layer sub-plate laser drilling alignment hole uses the Nth alignment target.
3. The method of manufacturing a high-density build-up circuit board according to claim 1, wherein In step S3, the laser drilling data is set in the position of the alignment target to form a positioning alignment hole, which is used for hole grasping and alignment during machine operation.
4. The method of manufacturing a high-density build-up circuit board according to claim 3, wherein The diameter of the positioning alignment hole is 2-4 mm.
5. The method of manufacturing a high-density build-up circuit board according to Claim 1, wherein In the exposure process, the first outer layer sub-plate pattern exposure uses the first alignment target as the alignment target, and in this way, the Nth outer layer sub-plate pattern exposure uses the Nth alignment target as the alignment target.
6. The method of manufacturing a high-density build-up circuit board according to claim 5, wherein On the pattern data of all outer layer sub-plates, the target position is provided with a target, which is used for pattern exposure alignment; the diameter of the target is 2-4 mm.
7. A method of processing a high-density build-up circuit board, characterized by, The method comprises the following steps: A. The inner layer sub-plate is made; specifically: cutting the core plate / conventional making multi-layer plate, machine drilling buried hole and tool hole, hole metallization, inner layer sub-plate pattern and target setting; B. The outer layer sub-plate is made; the method comprises the method for making according to any one of claims 1-6; C. The outer layer pattern post-process is made.