Manufacturing method of outer flexible layer rigid-flex board for intelligent visual module

Abstract

A manufacturing method of an outer flexible layer rigid-flexible combined board for an intelligent visual module comprises the following steps: manufacturing a flexible core board and a rigid core board attached with a release layer corresponding to an uncovering area, and then taking a prepreg layer and a copper layer; sequentially stacking and laminating the plates to form a laminated plate; the release layer faces the flexible core plate; the outer layer of the laminated plate is a flexible layer; a first through hole and a second through hole are drilled in the laminated plate, electroplating is carried out, depth-controlled drilling is carried out on the second through hole, the first through hole forms a conducting hole, the second through hole forms a depth-controlled hole, and the depth-controlled hole plate is integrally formed; resin hole plugging processing is carried out on the depth control hole, the depth control hole forms a solid via hole, then surface treatment and uncovering processing are carried out in sequence, then molding is carried out, and the whole board forms the rigid-flexible combined board; the processing flow is greatly simplified, and the processing precision is improved; and the thickness and rigidity of the integrally pressed plate body are enhanced, so that the stability in the polishing process is improved, and the problems of excessive polishing, excessive expansion and shrinkage or breakage of the flexible layer are effectively avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of circuit board processing, in particular to a manufacturing method of an outer flexible layer rigid-flexible combination board for intelligent visual modules. BACKGROUND

[0002] For some intelligent visual perception modules, due to the small installation space, high-density interconnection rigid-flexible combination boards are usually used to achieve the structure effect of small space three-dimensional assembly and high-density integration.

[0003] Further, in order to meet the needs of current or signal transmission in a specific layer and facilitate one-time bending installation, the flexible board layer is designed on the outermost layer, the circuit pattern and the rigid board layer realize high-density interconnection conduction, and the flexible board layer surface is also provided with a welding pad, thereby improving the surface utilization rate, the transmission efficiency of current and signal, and finally forming a rigid-flexible combination board with the flexible layer located on the outer layer and having a high-density interconnection structure.

[0004] However, the existing technology has the following defects in the processing method of such circuit boards: (1) If high-density interconnection is achieved by making a buried hole, the flexible board layer and the layer where the buried hole in the rigid board layer is located are laminated and pressed to form a first-stage core board, and then the processes of drilling, electroplating, resin hole plugging, baking and polishing are performed in turn, and then the whole board body is formed by lamination and pressing with other layers; but since the flexible board layer itself is soft and the copper layer is thin, the overall thickness of the first-stage core board is also thin, and during the polishing process, the board body is prone to breakage, excessive expansion or uneven expansion, which may further lead to board scrap or subsequent line production deviation.

[0005] (2) If the laminated blind hole form is used for manufacturing, it needs to be laminated, laser punched and filled with electroplating layer by layer, which not only greatly improves the processing precision requirement, but also significantly increases the complexity and cost of the processing process.

[0006] Based on the above background and problems, it is necessary to provide a new manufacturing method of an outer flexible layer rigid-flexible combination board for intelligent visual modules. SUMMARY

[0007] The present application aims to solve the comprehensive problems of poor processing precision of the existing rigid-flexible combination board with high-density interconnection structure and its flexible layer located on the outer layer, and provides a manufacturing method of an outer flexible layer rigid-flexible combination board for intelligent visual modules, which is processed according to design data, the design data is designed with a forming line, the area inside the forming line is an effective area, and other areas are invalid areas, the effective area includes a cover-uncovering area and a non-cover-uncovering area, the non-cover-uncovering area is designed with a through hole and a pad, and the manufacturing method comprises the following steps: S10: according to the design data to make the formation of flexible core plate, and make the corresponding cover area attached with the rigid core plate of the release layer, and take prepreg layer and copper layer; then the flexible core plate, the rigid core plate, the prepreg layer and the copper layer are stacked in turn, and are pressed together, and the whole plate is formed into a press plate; wherein, the release layer is towards the flexible core plate; the outer layer of the press plate is flexible layer; S20: drilling the first through hole and the second through hole to the press plate, and then electroplating, and controlling the depth of the second through hole by drilling, the first through hole forms the through hole, and the second through hole forms the depth control hole, and the whole forms the depth control hole plate; S30: resin plug processing is performed on the depth control hole, the depth control hole forms a solid through hole, and then surface treatment and cover processing are performed in turn, and then molding, the whole plate forms the rigid-flex combination plate; the cover processing is to control the depth of milling from the flexible core plate to the release layer.

[0008] Further, the flexible core plate is made by taking a double-sided flexible copper-clad plate, making a first circuit pattern on one side to form a single-sided patterned copper-clad plate, and taking a first flexible plate insulating medium layer and pressing it with the single-sided patterned copper-clad plate to form the flexible core plate; the first circuit pattern is towards the first flexible plate insulating medium layer; the stacking is that the first flexible plate insulating medium layer of the flexible core plate is towards the rigid core plate.

[0009] Further, the flexible core plate is made by taking a first single-sided flexible copper-clad plate and a second single-sided flexible copper-clad plate; a second circuit pattern is made on the second single-sided flexible copper-clad plate to form a second single-sided patterned copper-clad plate; the first single-sided flexible copper-clad plate is pressed with the second single-sided patterned copper-clad plate to form the flexible core plate; the second circuit pattern is towards the insulating medium layer of the first single-sided flexible copper-clad plate.

[0010] Further, one side of the flexible core plate towards the rigid core plate is attached with a reinforcing sheet; the reinforcing sheet corresponds to the area of the pad.

[0011] Further, the diameter of the depth control hole is single-sidedly larger than the diameter of the second through hole.

[0012] Further, the stacking includes setting a prepreg between the first single-sided flexible copper-clad plate and the second single-sided flexible copper-clad plate, making a window in the prepreg corresponding to the cover area, and making a second flexible plate insulating medium layer in the area of the window.

[0013] Further, the size of the second flexible plate insulating medium layer is single-sidedly larger than the cover area.

[0014] Further, a plurality of compensation holes same as the solid through hole are made in the invalid area adjacent to the solid through hole.

[0015] Further, the distance between adjacent compensation holes from the effective area to the invalid area increases in turn.

[0016] Further, the number of the compensation holes is greater than the number of the adjacent solid through holes, and the distribution area width of the compensation holes is greater than the distribution area width of the adjacent solid through holes.

[0017] The main beneficial effects of the technical solution include the following: (1) By using the processing flow of "direct overall compression → drilling of second through hole → drilling of control deep hole → resin hole plugging → polishing → post-process", instead of the multiple stacking and compression processing mode of the prior art, the processing flow is greatly simplified, the cumulative deviation of interlayer positioning caused by multiple compression can be avoided, the processing precision is improved, and the thickness and stiffness of the plate body after overall compression are enhanced, thereby improving the stability of the polishing process, effectively avoiding problems such as excessive polishing, excessive expansion or rupture of the flexible layer, and improving product quality and yield.

[0018] (2) By adding prepreg to the flexible plate layer, the prepreg is made to correspond to the uncovering area to make a window, a second flexible plate insulating medium layer is added to the windowed area, the non-uncovering area is directionally reinforced, and the flexible characteristics of the uncovering area are retained; on the one hand, the thickness of the flexible plate layer can be increased to improve the support of the plate body; on the other hand, the strength of the flexible plate layer is enhanced, the anti-polishing impact and pulling capacity are improved, the size stability of the plate body after polishing is ensured, and the polishing flatness is optimized.

[0019] (3) By setting a compensation plugging area, the compensation hole has the same structure as the solid through hole, the distance between adjacent compensation holes from the effective area to the invalid area increases in turn, and the number and distribution width of the compensation holes are greater than those of the adjacent solid through holes, so that the polishing pressure is stably increased and pre-stabilized, problems such as plate body pulling and damage caused by instantaneous change of the polishing pressure in the dense hole area are effectively avoided, and the polishing uniformity is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the drawings shown.

[0021] Figure 1 The process flowchart of the embodiment of the present application; Figure 2 The cross-sectional schematic view of the first stacking structure of the embodiment of the present application; Figure 3 A cross-sectional view of a second stacked structure according to an embodiment of the present application; Figure 4 A cross-sectional view of a third stacked structure according to an embodiment of the present application; Figure 5 A cross-sectional view of a press-bonding plate according to an embodiment of the present application; Figure 6 A cross-sectional view of a through-hole plate according to an embodiment of the present application; Figure 7 A cross-sectional view of a controlled depth hole plate according to an embodiment of the present application; Figure 8 A cross-sectional view of a solid plate according to an embodiment of the present application; Figure 9 A plan view of a distribution of holes to be sanded according to an embodiment of the present application; Figure 10 A cross-sectional view of a rigid-flexible combination plate according to an embodiment of the present application.

[0022] BRIEF DESCRIPTION OF DRAWINGS 100, forming line; 200, active area; 210, uncovering area; 220, non-uncovering area; 300, invalid area; 400, controlled depth milling line; 500, reinforcing sheet; 600, compensation hole; 700, solid through-hole area; 800, compensation plug hole area; 10, first stacked structure; 1010, flexible core plate; 1010L, another flexible core plate; 1010a, first circuit pattern; 1010b, copper foil; 1010c, first insulating medium layer; 1020, first flexible plate insulating medium layer; 1030, rigid core plate; 1030a, release layer; 1030d, rigid core plate copper layer; 1030c, rigid core plate insulating medium layer; 1040, prepreg layer; 1050, copper foil layer; 10A, second stacked structure; 1060, first single-sided flexible copper-clad plate; 1060a, first copper layer; 1060b, second insulating medium layer; 1070, second single-sided flexible copper-clad plate; 1070a, second circuit pattern; 1070b, third insulating medium layer; 10B, third stacked structure; 1080, prepreg; 1080a, second flexible plate insulating medium layer; 20, press-bonding plate; 2010, first through-hole; 2020, second through-hole; 30, through-hole plate; 3010, first through-hole; 3020, second through-hole; 40, controlled depth hole plate; 4010, controlled depth hole; 50, solid plate; 5010, solid through-hole; FX, direction of travel; 60, rigid-flexible combination plate; 6010, solder resist layer; 6020, cover film; 6030, surface treatment layer.

[0023] The objectives, features and advantages of the present application will be further illustrated with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all 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 effort belong to the scope of protection of the present application.

[0025] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.

[0026] In addition, the descriptions such as “first”, “second” and the like in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as “first”, “second” can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of “a plurality of” is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0027] In addition, the technical solutions of each embodiment of the present application can be combined with each other, but it must be based on the fact that a person of ordinary skill in the art can realize it, and when the combination of technical solutions contradicts each other or cannot be realized, it should be considered that the combination of technical solutions does not exist and is not within the scope of protection claimed by the present application.

[0028] In order to better understand the above technical solutions, the above technical solutions will be described in detail below with reference to the drawings.

[0029] Please refer to Figure 1 , Figure 1 for the process flowchart of the embodiment of the present application.

[0030] A manufacturing method of an outer flexible layer rigid-flex board for an intelligent vision module, the rigid-flex board 60 is processed according to design data, the design data is designed with a forming line 100, the area within the forming line 100 is an effective area 200, and other areas are invalid areas 300, the effective area 200 includes a cover opening area 210 and a non-cover opening area 220, the non-cover opening area 220 is designed with a through hole and a pad, a depth control milling cutting line 400, the manufacturing method includes Figure 1 The process flow shown in the figure is specifically described as follows.

[0031] Please refer to Figure 2 , Figure 3 , Figure 4 and Figure 5 , Figure 2This is a cross-sectional schematic diagram of the first stacked structure according to an embodiment of the present invention; Figure 3 This is a cross-sectional schematic diagram of the second stacked structure according to an embodiment of the present invention; Figure 4 This is a cross-sectional schematic diagram of the third stacked structure according to an embodiment of the present invention; Figure 5 This is a cross-sectional schematic diagram of the pressing plate according to an embodiment of the present invention.

[0032] Step S10: A flexible core board 1010 is fabricated according to the design data, and a rigid core board 1030 (including a rigid core board insulating dielectric layer 1030c and a rigid core board copper layer 1030d) with a release layer 1030a attached to the corresponding uncovering area 210 is also fabricated. Then, a semi-cured sheet layer 1040 and a copper layer (i.e., the copper foil layer 1050 in the attached figure) are taken. The flexible core board 1010, the rigid core board 1030, the semi-cured sheet layer 1040 and the copper foil layer 1050 are then stacked in sequence to form a stacked structure 10 and pressed together to form a press plate 20. The release layer 1030a faces the flexible core board 1010. The outer layer of the press plate 20 is a flexible layer.

[0033] By using a one-time stacking and pressing process, interlayer misalignment caused by multiple pressings is reduced, significantly improving the alignment accuracy between plate layers and providing processing conditions for subsequent drilling and deep hole 4010 machining.

[0034] Please refer to it again. Figure 2 .

[0035] Optionally, the flexible core board 1010 is fabricated by taking a double-sided flexible copper-clad laminate (including a first insulating dielectric layer 1010c), fabricating a first circuit pattern 1010a on one side and a copper foil 1010b on the other side to form a single-sided patterned copper-clad laminate 110, and taking a first flexible insulating dielectric layer 1020 and pressing it with the single-sided patterned copper-clad laminate 110 to form the flexible core board 1010; the first circuit pattern 1010a faces the first flexible insulating dielectric layer 1020; the stacking is such that the first flexible insulating dielectric layer 1020 of the flexible core board 1010 faces the rigid core board 1030, forming the first type of stacking structure 10.

[0036] It is worth noting that the double-sided flexible copper clad laminate must first have a first circuit pattern 1010a made on one side, and the remaining copper foil 1010b is located on the outermost layer of the first stacking structure 10, and then it is stacked and pressed together with other layers as a whole, which reduces the risk of alignment deviation and simplifies the processing procedure.

[0037] Please refer to it again. Figure 3 .

[0038] Optionally, another flexible core board 1010L is fabricated by taking a first single-sided flexible copper-clad laminate 1060 (including a first copper layer 1060a and a second insulating dielectric layer 1060b) and a second single-sided flexible copper-clad laminate 1070 (including a second copper layer and a third insulating dielectric layer 1070b); fabricating a second circuit pattern 1070a on the second copper layer of the second single-sided flexible copper-clad laminate 1070 to form a second single-sided patterned copper-clad laminate 1070; pressing the first single-sided flexible copper-clad laminate 1060 and the second single-sided patterned copper-clad laminate 1070 together to form another flexible core board 1010L; the second circuit pattern 1070a faces the second insulating dielectric layer 1060b of the first single-sided flexible copper-clad laminate 1060, forming a second type of stacked structure 10A.

[0039] First, the first single-sided flexible copper-clad laminate 1060 and the second single-sided flexible copper-clad laminate 1070 are pressed together to ensure high-precision processing of the second circuit pattern 1070a. Then, they are stacked and pressed together with other layers to effectively avoid the alignment deviation problem when multiple substrates are stacked at the same time. Furthermore, the second circuit pattern 1070a is tightly wrapped by the second insulating dielectric layer 1060b of the first single-sided flexible copper-clad laminate 1060. In the subsequent two hot pressing processes of pre-pressing and overall pressing, the scrapping of the board due to circuit damage is reduced.

[0040] Optionally, a reinforcing sheet 500 is attached to the side of the flexible core board 1010 facing the rigid core board 1030; the reinforcing sheet 500 corresponds to the area of ​​the pad.

[0041] By attaching reinforcing pads 500, the support for the pads can be increased, preventing the pads from sinking or deforming during soldering, thus ensuring the reliability and structural integrity of the solder joints.

[0042] It is worth noting that the reinforcing sheet 500 in this embodiment is pre-pressed into the board body, rather than being attached separately in the process before welding. By attaching it in batches as a whole, the attachment accuracy of the reinforcing sheet 500 can be effectively increased, and the precise alignment of the reinforcing sheet 500 with the pad can be achieved, avoiding problems such as alignment shift caused by manual operation or reference deviation when attaching it separately in the future.

[0043] Please refer to it again. Figure 4 .

[0044] Optionally, the stacking includes setting a prepreg 1080 between the first single-sided flexible copper clad laminate 1060 and the second single-sided flexible copper clad laminate 1070. The prepreg 1080 has an opening corresponding to the cover area 210. The area with the opening is provided with a second flexible board insulating dielectric layer 1080a, forming a third stacking structure 10B.

[0045] Since the flexible copper clad laminate formed by laminating the first single-sided flexible copper clad laminate 1060 and the second single-sided flexible copper clad laminate 1070 is a double-layer structure and relatively thin, its flexibility will be further enhanced after subsequent resin plugging and baking treatment. During the grinding process, the board body lacks sufficient rigid support, which can easily lead to problems such as excessive grinding and stretching, excessive expansion and contraction of the flexible board layer, or uneven expansion and contraction.

[0046] Therefore, by setting a prepreg 1080 between the first single-sided flexible copper clad laminate 1060 and the second single-sided flexible copper clad laminate 1070, and specifically making a window at the position corresponding to the uncovered area 210 of the prepreg 1080, and adding a second flexible board insulating dielectric layer 1080a in the windowed area, the functional partitioning of the flexible layer is formed, and the rigid area (non-covered area 220) that needs to withstand grinding stress is strengthened, so that the flexible core board 1010 can resist the pulling force and pressure of the sanding belt during grinding, effectively avoiding the problems of excessive grinding, excessive expansion and contraction, or unevenness of the flexible board layer.

[0047] Optionally, the dimensions of the second flexible plate insulating dielectric layer 1080a are larger on one side than the uncovered area 210.

[0048] This structure, equivalent to the second flexible board insulating dielectric layer 1080a extending into the board body, can effectively prevent the exposure of circuit patterns due to insufficient size of the flexible board's cover film layer after subsequent processing.

[0049] Please see Figure 6 and Figure 7 , Figure 6 This is a cross-sectional schematic diagram of the through-hole plate according to an embodiment of the present invention; Figure 7 This is a cross-sectional schematic diagram of the depth control plate according to an embodiment of the present invention.

[0050] Step S20: Drill a first through hole 2010 and a second through hole 2020 into the press plate 20, and then electroplate it. The first through hole 2010 forms a first through hole 3010, and the second through hole 2020 forms a second through hole 3020, forming a through hole plate 30. Drill a controlled depth hole into the second through hole 3020, forming a controlled depth hole 4010, and the whole thing forms a controlled depth hole plate 40.

[0051] By completing the processing steps of through holes, electroplating and controlled depth drilling (i.e., back drilling) in one go on the laminating plate 20, the circuit conduction between specific layers is formed. This eliminates the traditional blind hole process of layer-by-layer laser drilling and hole filling electroplating, and then layer-by-layer lamination, which effectively shortens the processing cycle.

[0052] Furthermore, because the overall pressed board is thicker and more stable, drilling and depth control processing at this stage are less likely to cause board deformation or cracking compared to traditional thin core board processing in stages, thus effectively improving processing accuracy.

[0053] Optionally, the diameter of the depth control hole 4010 is larger on one side than the diameter of the second through hole 3020.

[0054] The diameter of the controlled depth drilling 4010 is larger than the diameter of the second through hole 3020, which effectively cooperates with the controlled depth drilling process to remove the deep copper in the second through hole 3020 that does not need to be connected, thereby realizing the connection between specific copper layers.

[0055] It is worth noting that the diameter difference between the two and the chamfer formed by drilling need to be controlled within a reasonable size range. If the difference on one side is too large, a large step difference will be formed at the junction of the depth control hole 4010 and the second through hole 3020. When filling with resin, it is easy to form a flow dead corner at the step corner, resulting in air bubbles being hidden or incomplete filling. If the difference is too small, it will not meet the cutting requirements of the copper hole that does not need to be conductive.

[0056] Therefore, preferably, the diameter of the control hole 4010 is 10μm to 50μm larger on each side than the diameter of the second via 3020, following the principle that the smaller the value, the better, to ensure copper stripping and guarantee the accuracy of copper layer interconnection.

[0057] Please see Figure 8 , Figure 9 and Figure 10 , Figure 8 This is a cross-sectional schematic diagram of a solid plate according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the distribution of grinding holes in the belt to be sanded according to an embodiment of the present invention; Figure 10 This is a cross-sectional schematic diagram of the rigid-flexible plate according to an embodiment of the present invention.

[0058] Step S30: The controlled depth hole 4010 is filled with resin to form a solid through hole 5010, and the whole board is formed into a solid board 50. Then, surface treatment and capping are performed in sequence, and then the board is formed into a rigid-flexible board 60 (including a solder resist layer 6010, a cover film 6020 and a surface treatment layer 6030, wherein the surface treatment layer 6030 is located as a solder pad). The capping process is to perform controlled depth milling from the flexible core board 1010 to the release layer 1030a along the controlled depth milling line 400.

[0059] The controlled depth hole 4010 is filled with resin, forming a solid through hole 5010, which is equivalent to a blind hole. Combined with the previous processing, the entire technical solution uses the method of "full lamination + making through holes + drilling controlled depth holes 4010 (back drilling) + resin filling" to replace the buried hole processing of the existing technology, reducing the processing difficulty, improving the processing accuracy, and increasing the thickness of the board after full lamination, which makes the subsequent resin filling and grinding easier and can effectively prevent problems such as grinding cracks and excessive expansion and contraction.

[0060] Please refer to it again. Figure 9 During the grinding process, the solid plate 50 moves forward along the direction of travel FX.

[0061] Optionally, the invalid region 300 adjacent to the solid through hole 5010 is provided with a plurality of compensation holes 600 identical to the solid through hole 5010.

[0062] If the controlled depth holes 4010 are densely distributed, and the protruding resin after plugging and baking is too dense, grinding with a belt abrasive can be used. Since the grinding process involves adjusting the downward pressure as needed, the grinding pressure is relatively low when grinding areas without solid through holes 5010, but increases when grinding areas with solid through holes 700. If the protruding resin is too dense, the downward pressure will increase instantaneously, generating a large grinding force on other areas 700 of the board without solid through holes, which can easily cause grinding damage, over-grinding, or unevenness. Although multiple grinding sessions can improve this problem, it can easily lead to excessive stretching of the board, increased probability of grinding damage, and increased costs.

[0063] Therefore, a compensation plugging area 800 is provided in the ineffective area 300 of the solid through hole area 700 of the resin plugging hole, which is composed of a number of compensation holes 600. Specifically, during grinding, the compensation plugging area 800 first enters the grinding belt position, at which point the grinding pressure begins to increase. This pressure is maintained and the grinding enters the solid through hole area 700 of the resin plugging hole for grinding.

[0064] On the one hand, it solves the problem of grinding damage. The pre-pressure adjustment of the compensation plugging area 800 ensures that the solid through-hole area 700 is subjected to uniform force during grinding, avoiding defects such as excessive grinding of the board, cracking of the flexible layer, or uneven expansion and contraction caused by the instantaneous increase of downward pressure. This greatly improves the flatness and structural integrity of the board surface and reduces the product scrap rate. On the other hand, it also simplifies the grinding process. Uniform processing can be achieved in one grinding, which avoids excessive stretching of the board caused by multiple grindings and improves production efficiency.

[0065] Optionally, the spacing between adjacent compensation holes 600 increases sequentially from the effective region 200 to the ineffective region 300.

[0066] With the spacing of the compensation holes 600, the plate enters the sanding belt position, and the downward pressure gradually increases until it reaches a stable force.

[0067] On the one hand, the gradient spacing design of the compensation holes 600 allows the grinding belt to gradually adjust the pressure according to the hole density, ensuring that the pressure smoothly transitions from the initial value to a stable value. This effectively avoids problems such as plate pulling, twisting, or flexible layer cracking caused by a sudden increase in force. On the other hand, the smooth increase in pressure also increases the uniformity of grinding, ensuring that the grinding force state remains consistent before and after the plate enters the solid through hole area 700, thus guaranteeing the overall flatness of the plate surface.

[0068] Optionally, the number of overall compensation holes 600 is greater than the number of adjacent overall solid through holes 5010, the width of the distribution area of ​​the overall compensation holes 600 is greater than the width of the distribution area of ​​the adjacent overall solid through holes 5010, and the adjacent compensation holes 600 are evenly distributed in the length direction, with the width being perpendicular to the line connecting the invalid area 300 and the effective area 200.

[0069] By increasing the number of compensation holes 600 and the wider distribution area, the sanding belt can fully adjust and stabilize its downward pressure before entering the solid through hole area 700, avoiding uneven sanding in the hole area due to unstable pressure, forming a uniform and continuous sanding effect, and greatly improving the flatness of the board surface.

[0070] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made under the inventive concept of the present invention using the description and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for manufacturing an outer flexible rigid-flex board for an intelligent vision module, wherein the rigid-flex board is processed according to design data, the design data includes forming lines, the area within the forming lines is an effective area, and other areas are ineffective areas, the effective area includes a covered area and a non-covered area, the non-covered area is designed with vias and pads, characterized in that, The manufacturing method includes the following steps: S10: A flexible core board is formed according to the design data, and a rigid core board with a release layer attached to the corresponding uncovering area is formed. Then, a semi-cured sheet and a copper layer are taken. The flexible core board, the rigid core board, the semi-cured sheet, and the copper layer are then stacked and pressed together to form a laminated board. The release layer faces the flexible core board; the outer layer of the press-fit plate is a flexible layer; S20: Drill a first through hole and a second through hole into the press plate, then electroplate, and perform controlled-depth drilling on the second through hole. The first through hole forms the through hole, and the second through hole forms the controlled-depth hole. The whole plate is formed into a controlled-depth hole plate. S30: The depth control hole is resin plugged to form a solid through hole. Then, surface treatment and capping are performed in sequence, and then the whole plate is formed into the rigid-flexible plate. The peeling process involves controlled-depth milling from the flexible core board to the release layer.

2. The method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 1, characterized in that, The flexible core board is fabricated by taking a double-sided flexible copper-clad laminate, fabricating a first circuit pattern on one side to form a single-sided patterned copper-clad laminate, and taking a first flexible board insulating dielectric layer and pressing it with the single-sided patterned copper-clad laminate to form the flexible core board; the first circuit pattern faces the first flexible board insulating dielectric layer. The stacking arrangement is such that the first flexible insulating dielectric layer of the flexible core board faces the rigid core board.

3. The method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 1, characterized in that, The flexible core board is fabricated by taking a first single-sided flexible copper-clad laminate and a second single-sided flexible copper-clad laminate. A second circuit pattern is fabricated on the second single-sided flexible copper-clad laminate to form a second single-sided patterned copper-clad laminate; The first single-sided flexible copper-clad laminate and the second single-sided patterned copper-clad laminate are pressed together to form the flexible core board; the second circuit pattern faces the insulating dielectric layer of the first single-sided flexible copper-clad laminate.

4. A method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 2 or 3, characterized in that, A reinforcing sheet is attached to the side of the flexible core board facing the rigid core board; the reinforcing sheet corresponds to the area of ​​the solder pad.

5. The method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 1, characterized in that, The diameter of the depth control hole is larger on one side than the diameter of the second through hole.

6. The method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 3, characterized in that, The stacking includes a prepreg placed between the first single-sided flexible copper-clad laminate and the second single-sided flexible copper-clad laminate. The prepreg has an opening corresponding to the uncovered area, and a second flexible board insulating dielectric layer is formed in the area of ​​the opening.

7. The method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 6, characterized in that, The size of the insulating dielectric layer of the second flexible board is larger on one side than the uncovered area.

8. The method for manufacturing a flexible outer layer rigid-flex plate for an intelligent vision module as described in claim 1, characterized in that, The invalid region adjacent to the solid through hole is provided with a plurality of compensation holes identical to the solid through hole.

9. The method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 8, characterized in that, The spacing between adjacent compensation holes increases sequentially from the effective region to the ineffective region.

10. The method for manufacturing an outer flexible layer rigid-flex plate for an intelligent vision module as described in claim 9, characterized in that, The overall number of compensation holes is greater than the number of adjacent overall solid through holes, and the width of the distribution area of ​​the overall compensation holes is greater than the width of the distribution area of ​​adjacent overall solid through holes.

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