A method for manufacturing an aluminum-based multilayer rigid-flex combination board with high heat dissipation

Abstract

The application discloses a manufacturing method of an aluminum-based multilayer rigid-flex combination plate with high heat dissipation, which comprises the following steps: structure splitting of the multilayer rigid-flex combination plate, which is divided into a first copper layer and a multilayer flexible plate core layer; attaching the first copper layer to an aluminum substrate; manufacturing a circuit pattern and a through hole, including a pin hole; then, windowing; manufacturing other layers to form the core layer; then, manufacturing a glue layer and attaching a cover film layer; manufacturing a through hole, including a pin hole; taking a second cover film layer, including a cover film pin hole; stacking and pressing each layer; then, performing electroplating processing and back drilling processing to form the aluminum-based multilayer rigid-flex combination plate. Through the manufacturing method, the problems of displacement and shift of the aluminum substrate and the multilayer flexible plate during pressing, short circuit or open circuit caused by surface depression, large vibration of depth control milling plate, hole skew and glue overflow in the hole of the multilayer flexible plate caused by pressing and other problems can be effectively prevented.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of flexible circuit board or rigid-flex board manufacturing, in particular to a manufacturing method of high-heat-dissipation aluminum-based multilayer rigid-flex board. BACKGROUND

[0002] For a kind of rigid-flex board applied to intelligent network connected car, low-altitude aircraft, not only require flexible installation characteristics, also need to have the ability of bearing multiple signal transmission, thus be designed as multilayer flexible plate structure, in addition, high heat dissipation performance is required, thus select aluminum-based layer as heat dissipation layer, and the overall structure forms aluminum-based rigid-flex board.

[0003] In prior art, aluminum-based multilayer rigid-flex board generally adopts similar manufacturing method of ordinary rigid-flex board, that is, multilayer flexible plate layer is manufactured, cover film is attached to the area of subsequent formed rigid-flex area, aluminum-based plate is manufactured, blind groove is manufactured to the edge of the area of aluminum-based plate needing to be uncovered, aluminum-based plate is laminated with multilayer flexible plate layer, then outer layer circuit pattern is manufactured and surface cover film is attached, and uncovering processing is carried out, to form aluminum-based rigid-flex board.

[0004] The disadvantages of prior art are:

[0005] The expansion and contraction rate of multilayer flexible plate layer is much larger than that of aluminum-based plate, and the thickness of aluminum-based plate is generally thick, if the pressing force is too large when laminating the two, it is easy to cause the problems of excessive expansion and contraction deviation and displacement, or the problems of deviation and displacement in the pressing process caused by the thickness of aluminum-based plate being too thick, and if the pressing force is too small, it is easy to cause the problems of poor pressing and delamination.

[0006] The method of manufacturing blind groove of aluminum-based plate, then laminating and then manufacturing outer layer circuit, after laminating, the multilayer flexible plate layer corresponding to the position of blind groove is easy to be concave, which is easy to cause short circuit or open circuit in the manufacturing of outer layer circuit pattern.

[0007] Since multilayer flexible plate layer is manufactured first and then laminated, the hole of multilayer flexible plate layer forms a through hole after electroplating, which is easy to cause problems such as through hole skew and glue overflow in the hole during laminating.

[0008] During uncovering processing, controlled depth milling plate is used, and it is difficult to control the depth, too large depth is easy to damage the surface of multilayer flexible plate layer, and too small depth is difficult to uncover due to insufficient milling of aluminum-based plate, and controlled depth milling plate needs to use milling cutter for transverse milling, which generates large vibration during processing, and is easy to cause delamination between aluminum-based plate and multilayer flexible plate layer and other problems.

[0009] Based on the above background and problems, it is necessary to provide a manufacturing method of high-heat-dissipation aluminum-based multilayer rigid-flex board. SUMMARY

[0010] The present application aims to solve the problems of the prior art, such as the easy occurrence of deviation, open circuit or short circuit of the outer circuit pattern, glue overflow in the hole, and damage to the multilayer flexible plate during the depth control milling of the aluminum-based multilayer rigid-flex combination plate, and proposes a manufacturing method of a high-heat-dissipation aluminum-based multilayer rigid-flex combination plate, comprising the following steps:

[0011] S10: The structure of the multilayer rigid-flex combination plate is split into a first copper layer and a multilayer flexible plate core layer, the aluminum substrate and the first adhesive layer are taken, the first adhesive layer and the first copper layer are attached to the surface of the aluminum substrate in turn, and then they are pressed together to form an aluminum-based copper-clad plate.

[0012] S20: The first copper layer of the aluminum-based copper-clad plate is manufactured into a copper layer circuit pattern, and an aluminum substrate through hole is manufactured, which includes an aluminum substrate pin hole, and then an aluminum substrate window area is manufactured to form a windowed aluminum substrate.

[0013] S30: The core layer of the multilayer flexible plate is manufactured according to a predetermined process, and a surface pattern layer of the core layer is formed; the second adhesive layer is taken and attached to the core layer; then the first cover film is taken, a first cover film pattern is manufactured to form a first cover film layer, the first cover film layer is attached to the surface of the second adhesive layer, and the first cover film layer corresponds to the aluminum substrate window area; a cover film flexible plate is formed as a whole; a cover film flexible plate through hole is manufactured in the cover film flexible plate, which includes a flexible core plate pin hole; and a flexible adhesive plate is formed as a whole.

[0014] S40: The second cover film is taken, a second cover film pattern is manufactured to form a second cover film layer, and the second cover film pattern includes a cover film pin hole; the second cover film layer, the flexible adhesive plate, and the windowed aluminum substrate are stacked in turn from bottom to top and placed in a pressing device for overall plate pressing; and a pressed plate is formed as a whole.

[0015] S50: The pressed plate is subjected to electroplating processing and back drilling processing to form the aluminum-based multilayer rigid-flex combination plate.

[0016] Further, the overall plate pressing further comprises: manufacturing a pressing mold, the surface of the pressing mold is provided with a pin, and the pressing mold is arranged on the surface of the lower table of the pressing device; and the stacking from bottom to top in turn comprises: the cover film pin hole, the flexible core plate pin hole, and the aluminum substrate pin hole are sequentially and correspondingly sleeved on the pin from bottom to top.

[0017] Further, the overall plate pressing further comprises: manufacturing an air bag, the air bag is a structure of inflating inside a sealed plastic layer, and the air bag is arranged on the upper table of the pressing device.

[0018] Further, the forming the laminated board further comprises: taking a third adhesive layer, and making an adhesive layer window area corresponding to the first cover film layer, and making an adhesive layer through hole comprising an adhesive layer pin hole; integrally forming a window adhesive layer; the self-bottom-to-top sequentially stacking comprises: sequentially corresponding the cover film pin hole, the flexible core board pin hole, the adhesive layer pin hole, and the aluminum base plate pin hole to the pin in a bottom-to-top manner.

[0019] Further, after the making the aluminum base plate window area, brown processing is performed.

[0020] Further, before the electroplating processing of the laminated board, drilling processing is performed on the laminated board, and the drilling is performed according to a drilling pattern of the aluminum base multi-layer rigid-flex combination board.

[0021] Further, after the drilling processing, the laminated board is sequentially subjected to laser ablation, plasma treatment, and alkali washing treatment; the laser ablation is laser ablation on the stepped position of the aluminum base plate window area and the first cover film layer.

[0022] Further, the size of the aluminum base plate window area is smaller than the size of the first cover film layer on a single side.

[0023] Further, the back drilling processing is back drilling processing on the aluminum base plate through hole.

[0024] Further, the laminating device is a rigid plate laminating machine; and the parameters of the laminating of the whole board are as follows: the temperature rising rate is 2-6 ℃ / min, the highest temperature is 160-180 ℃, the pressure is 15-25 kg / cm2, and the temperature falling rate is 10-20 ℃ / min.

[0025] The technical scheme of the present application splits the structure of the multilayer flexible circuit board, first presses the outer circuit layer on the aluminum substrate to form a reverse structure, then laminates with other layers, combines the brown processing, and uses the pin matching pin hole processing method to effectively prevent the problems of deviation and displacement caused by the large difference in expansion and contraction rate and the sliding of the board during the lamination of the aluminum substrate and the multilayer flexible circuit board; the whole lamination process is formed by first manufacturing the windowed aluminum substrate (forming a single aluminum substrate), then using the reverse structure described above, first manufacturing the outer circuit pattern and the cover film layer of the flexible circuit board, and setting the lower platform with the lamination mold and the upper platform with the air bag, effectively improving the problem of short circuit or open circuit of the circuit pattern caused by the depression of the surface of the flexible circuit board after lamination; and first manufacturing the windowed aluminum substrate (forming a single aluminum substrate) can effectively prevent the delamination problem between the aluminum substrate and the multilayer flexible circuit board caused by the large vibration of the depth control milling plate; the through hole is first manufactured, the hole is repaired after the whole lamination, and the through hole is formed by electroplating, and then the hole of the aluminum substrate layer is back-drilled to effectively manufacture the through hole of the multilayer flexible circuit board, preventing the problems of hole skew and glue overflow in the hole caused by lamination after the through hole of the multilayer flexible circuit board is first manufactured. BRIEF DESCRIPTION OF DRAWINGS

[0026] 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.

[0027] Figure 1 Process flow chart of the present application embodiment;

[0028] Figure 2 Cross-sectional structure schematic diagram of the present application embodiment for manufacturing aluminum-based patterned board;

[0029] Figure 3 Cross-sectional structure schematic diagram of the present application embodiment for manufacturing aluminum-based patterned board;

[0030] Figure 4 Planar structure schematic diagram of the present application embodiment for manufacturing a whole single aluminum substrate;

[0031] Figure 5 Cross-sectional structure schematic diagram of the present application embodiment for manufacturing flexible adhesive plate;

[0032] Figure 6 Cross-sectional structure schematic diagram of the present application embodiment for forming lamination layout structure;

[0033] Figure 7 This is a schematic cross-sectional structure diagram of the press plate formed according to an embodiment of the present invention;

[0034] Figure 8 This is a schematic diagram of the cross-sectional structure of an aluminum-based multilayer rigid-flexible plate fabricated according to an embodiment of the present invention.

[0035] Explanation of icon numbers:

[0036] Reference Name Reference Name 10 Aluminum-based copper-clad plate 30B First cover film layer 110 Aluminum substrate 310B Cover film pinhole 120 First adhesive layer 30C Second cover film layer 130 First copper layer 310C Adhesive layer windowing area 20 Windowed aluminum substrate 3110C Adhesive layer via 210 Aluminum substrate via 3111C Adhesive layer pinhole 2110 Aluminum substrate pinhole 410 Stacked structure 220 Aluminum substrate windowing area 420 Lower deck 1310 Copper layer circuit pattern 430 Pressing mold 1311 Brown surface 430A Pin 230 Individual aluminum substrate 4310 First release layer 2310 Aluminum substrate connecting line 4320 Covering film 30 Flexible adhesive plate 4330 Second release film 30A Core plate layer 4340 Third release film 310 Cover film flexible plate via 440 Air bag 3110 Flexible core plate pinhole 450 Upper deck 320 Surface pattern layer 50 Pressing plate 330 Insulating dielectric layer 510 Trimming hole 340 Inner layer pattern layer 520 Excess adhesive 350 Second adhesive layer 60 Aluminum-based multilayer rigid-flexible combined plate 360 First cover film layer 610 Electroplated copper layer 40 Pressing layout structure 620 Back-drilling hole

[0037] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0038] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be noted that all directional indications (such as up, down, left, right, front, back, inside, outside, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0040] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0041] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0042] Please see Figure 1 , Figure 1 This is a process flow diagram of the manufacturing method of the present invention.

[0043] The method for manufacturing a high heat dissipation aluminum-based multilayer rigid-flex plate according to embodiments of the present invention includes:Figure 1 The key process flow is shown, and the specific implementation steps are as follows.

[0044] Step S10:

[0045] The structure of the multi-layer rigid-flex combined board is split into a first copper layer and a multi-layer flexible board core layer. The aluminum substrate 110 and the first adhesive layer 120 are taken, and the first adhesive layer 120, the first copper layer 130 are attached to the surface of the aluminum substrate 110 in turn, and are pressed to form an aluminum-based copper-clad plate 10.

[0046] The present embodiment splits the original multi-layer flexible circuit board structure according to the number of copper layer circuits, independently manufactures one of the surface circuit layers on the aluminum substrate 110 to form the aluminum-based copper-clad plate 10, and processes the other layers through subsequent processes to form the flexible adhesive plate 30. The aluminum substrate 110 is first attached with a first adhesive layer 120 and a first copper layer 130, which facilitates the expansion and contraction matching of the aluminum-based copper-clad plate 10 and the flexible adhesive plate 30 formed in subsequent processing, and prevents the problems of offset and displacement during pressing.

[0047] Step S20:

[0048] The first copper layer 130 of the aluminum-based copper-clad plate 10 is processed to form a copper layer circuit pattern 1310, and an aluminum substrate through hole 210 is formed, which includes an aluminum substrate pin hole 2110. Then, an aluminum substrate windowed area 220 is formed, followed by brown oxidation to form a brown oxidation surface 1311. The whole forms a windowed aluminum substrate 20.

[0049] The first copper layer 130 is processed to form a copper layer circuit pattern 1310 according to the original design of the multi-layer flexible circuit board, which is the outer layer circuit pattern in contact with the aluminum substrate 110. That is, the outer layer circuit pattern of the multi-layer flexible circuit board is transferred to the aluminum substrate 110 for processing. The aluminum substrate windowed area 220 is the position of the flexure area of the finally formed aluminum-based rigid-flex combined board 60. The brown oxidation forms a more effective uniform rough surface on the copper surface, increases the friction and bonding force between the pressing layers, and can form better bonding force with other adhesive layers during subsequent pressing, and can prevent the problems of offset and displacement during pressing. The aluminum substrate pin hole 2110 is used for matching the pin 430A of the pressing mold 430 during subsequent pressing. It is worth noting that if the copper layer circuit pattern 1310 has a through hole with a diameter greater than or equal to 0.5mm on the surface, and the through hole needs to be connected to the through holes of other layers in subsequent processing, the aluminum substrate pin hole 2110 can be formed at the position of the through hole.

[0050] It is worth mentioning that after the aluminum substrate is windowed, each independent single aluminum substrate 230 to be laminated can be formed, and the flexible circuit board is processed in a panel manner during processing. The panel structure has a "tool pattern area", that is, an invalid area that needs to be removed finally. The position distribution of the tool pattern area corresponding to the aluminum substrate 110 and the position pattern that the single aluminum substrate 230 needs to be laminated are used to set the aluminum substrate connecting line 2310 between each single aluminum substrate 230, so that the single aluminum substrate 230 forms a whole, facilitating subsequent lamination and lamination processing.

[0051] Step S30:

[0052] The core layer 30A of the multilayer flexible board is manufactured according to the predetermined process, and the surface pattern layer 320 of the core layer 30A is formed. The core layer 30A is the other layers of the originally designed multilayer flexible circuit board except the first copper layer 130 transferred to the aluminum substrate 110, for example Figure 5 As shown in the formula, a double-sided flexible copper-clad plate is taken, including an insulating medium layer 330, and double-sided patterns are manufactured, which are the surface pattern layer 320 and the inner layer pattern layer 340, respectively.

[0053] The second adhesive layer 350 is taken, and the second adhesive layer 350 is attached to the core layer 30A. Since the core layer 30A needs to be laminated with the windowed aluminum substrate 20 subsequently, the second adhesive layer 350 plays a role of bonding and interlayer insulation, and the second adhesive layer 350 is equivalent to the insulating medium layer below the copper layer circuit pattern 1310 of the original multilayer flexible circuit board structure.

[0054] Subsequently, the first cover film is taken, the first cover film pattern is manufactured to form the first cover film layer 360, the first cover film layer 30B is attached to the surface of the second adhesive layer 340, the first cover film layer 360 corresponds to the aluminum substrate windowed area 220, and the size of the aluminum substrate windowed area 220 is smaller than the size of the first cover film layer 360 on one side.

[0055] The first cover film layer 360 is the cover film layer of the flexible area of the finally formed aluminum rigid-flex combination board. Therefore, the first cover film layer 360 is arranged corresponding to the aluminum substrate windowed area 220, and the first cover film layer 360 needs to be laminated under the windowed aluminum substrate 20. Therefore, the size of the aluminum substrate windowed area 220 needs to be smaller than the size of the first cover film layer 360 on one side. Generally, the size is smaller by 10 μm to 50 μm on one side. The overall processing forms a cover film flexible board.

[0056] A cover film flexible board through hole 310 is manufactured on the cover film flexible board, and the cover film flexible board through hole 310 includes a flexible core plate pin hole 3110. The flexible board pin hole 3110 is also used for matching the pin 430A of the laminating mold 430 during subsequent lamination, and the overall processing forms a flexible adhesive plate 30.

[0057] Step S40:

[0058] Take the second cover film, make the second cover film pattern, form the second cover film layer 30B, and the second cover film pattern includes the cover film pin hole 310B; the cover film pin hole 310B is also used for matching the pin of the pressing die 430 during subsequent pressing.

[0059] In one embodiment, take the third glue layer, and make the glue layer windowed area 310C corresponding to the first cover film layer 360, and make the glue layer through hole 3110C including the glue layer pin hole 3111C; and the whole forms the windowed glue layer 30C.

[0060] Because the second glue layer 350 already exists, the windowed glue layer 30C is an optional glue layer, but in order to prevent the problem of easy deviation and displacement of the flexible adhesive plate 30 and the windowed aluminum substrate 20 during subsequent pressing, the windowed glue layer 30C can better improve the interlayer bonding effect and glue filling effect during pressing.

[0061] Make the pressing die 430, and the pressing die 430 is provided with a pin 430A on the surface, and the pressing die 430 is arranged on the surface of the lower table 420 of the pressing equipment.

[0062] The second cover film layer 30B, the flexible adhesive plate 30, and the windowed aluminum substrate 20 are sequentially stacked from bottom to top to form a stacking structure 410, and are placed in the pressing equipment for whole plate pressing; further, the cover film pin hole, the flexible core plate pin hole, and the aluminum substrate pin hole are sequentially and correspondingly sleeved on the pin from bottom to top; further, if the windowed glue layer 30C is arranged, the windowed glue layer 30C is arranged between the flexible adhesive plate 30 and the windowed aluminum substrate 20, and the glue layer pin hole is arranged corresponding to the flexible core plate pin hole.

[0063] In the prior art, the aluminum substrate 110 is directly pressed with the multilayer flexible circuit board, the thickness of the aluminum substrate 110 is thicker than that of the multilayer flexible circuit board, and the difference in expansion and contraction is too large, so in the embodiment, the pressing die 430 with a pin is arranged on the lower table of the pressing equipment, and the corresponding pin hole is arranged on the stacking structure 410 during pressing; during pressing, the edges of each layer are fixed by using the traditional hot melting or rivet method, and then the pin holes of each layer structure are correspondingly sleeved into the pin 430A, and the pin holes are further used to fix each layer plate during the pressing process, so that a stable pressing process is formed, and the deviation and displacement problems during the pressing process are prevented.

[0064] It is worth noting that the height of the protrusion of the pin 430A from the surface of the pressing mold 430 is 5μm to 35μm smaller than the thickness of the pressing plate 50 formed after pressing, preferably 10μm or 15μm smaller.

[0065] In one embodiment, because release layers and covering layers need to be provided on the upper and lower surfaces of the stacked structure 410 during the pressing process, it cannot be completely guaranteed that the pin 430A will not hit the release layer or covering layer, nor can it be completely guaranteed that the pin 430A will be flush with the thickness of the pressing plate 50. Therefore, a pre-pressing device can be used for pre-pressing, and the pressing mold 430 is placed on the pre-pressing device. Pre-pressing generally uses a lower temperature, shorter time, and lower pressure than the formal pressing to form a pre-pressed state for each layer before placing it into the pressing device for formal pressing. For example, pre-pressing uses a temperature of 130°C to 150°C and a pressure of 10 kg / cm². 2 Up to 20kg / cm 2 Pre-compression is performed under pressure for 60 to 90 seconds, followed by formal compression at a temperature of 160°C to 180°C and a pressure of 15 kg / cm². 2 Up to 25kg / cm 2 The pressure and time of 7 to 15 minutes are used to quickly press the flexible circuit board using a rapid pressing device.

[0066] For the upper platform 440 of the pressing equipment, an airbag 450 is made. The airbag 450 is a structure with air inside a sealed plastic layer. The airbag 450 is set on the upper platform 440 of the pressing equipment.

[0067] The airbag 450 in this embodiment has a flat structure with a thickness of 1.0 mm to 5.0 mm. The airbag 450 can be made of PP, PE, PET, or PTFE, with PTFE being the preferred material. The airbag is inflated in an unsaturated state and can be fixed to the upper table 440 of the pressing equipment by adhesive or edge nailing. Since the pressing layout structure 40 has an aluminum substrate window area 220 and is oriented upwards, a layout structure with a good upper surface for covering is required for covering. The airbag 450 structure can effectively buffer the covering and improve the flatness of the aluminum-based multilayer rigid-flexible board pressing.

[0068] It is worth noting that a first release layer 4310, a covering layer 4320, and a second release layer 4330 are sequentially laid on the pressing mold 430. The release layer is fitted onto the corresponding pin 430A to cover and release the pin. A third release layer 4340 is laid on the surface of the airbag 450 to release the airbag.

[0069] After the above layout, a pressed layout structure 40 is formed.

[0070] In one embodiment, the pressing device is a rigid plate press; the parameters of the whole plate pressing are as follows: the temperature rising rate is 2-6°C / min, the highest temperature is 160-180°C, the pressure is 15-25 kg / cm 2 2 and the temperature falling rate is 10-20°C / min; if better interlayer bonding effect and better pressing stability are needed, the rigid plate press can be used for pressing.

[0071] After pressing, the whole forms a pressed plate 50.

[0072] Step S50:

[0073] Optionally, first, the pressed plate 50 is drilled to form a trimming hole 510, and the drilling is performed according to the drilling pattern of the aluminum-based multilayer rigid-flex combined plate.

[0074] Here, the drilling is trimming drilling, because after pressing, there may be problems such as uneven inner wall of the hole, and by trimming the hole shape, it is regular, which is convenient for subsequent copper plating hole processing.

[0075] After drilling, laser ablation, plasma treatment and alkali washing treatment are sequentially performed; the laser ablation is performed on the stepped position of the aluminum substrate window area 220 and the first cover film layer 360.

[0076] Because after pressing, the stepped position of the first cover film layer 360 may produce overflow 520, the overflowed glue is burned off by laser ablation, and after laser ablation, carbon black impurities will appear, and after trimming drilling, there are drilling dirt impurities, so by plasma treatment and alkali washing treatment, the carbon black impurities and drilling dirt impurities can be effectively removed.

[0077] Then, the pressed plate 50 is subjected to electroplating processing to form an electroplated copper layer 610, and back drilling processing is performed to form a back drilling hole 620, and the back drilling processing is performed on the aluminum substrate through hole 210, and optionally, the depth of the back drilling hole 620 is 5-50 μm larger than the depth of the aluminum substrate through hole 210, thereby forming the aluminum-based multilayer rigid-flex combined plate 60.

[0078] ​Since the flexible adhesive plate 30 is first made with the surface pattern layer 320, and then the second cover film layer 30B is attached by pressing, a multilayer flexible circuit layer structure is formed, but the layers of the multilayer need to be connected through the through hole, so it also needs electroplating processing. The present embodiment places electroplating after the processing of the surface pattern layer 320 and the processing of the second cover film layer 30B, effectively preventing the original processing process of first pressing between the multilayer, then drilling and electroplating through holes, and then making the outer circuit pattern, which is prone to surface depression, and further causes the problem of short circuit or open circuit of the circuit pattern.

[0079] After electroplating, the inner wall of the aluminum substrate via hole 210 of the aluminum substrate 110 is also electroplated with copper. Through the processing of back drilling, the copper on the inner wall of the aluminum substrate via hole 210 is effectively removed, preventing the problem of short circuit.

[0080] It is worth noting that due to the precision of the flexible circuit board in actual design and processing process, the actual structure diagram and the thickness of each layer, the line width and other dimensions are all in microns, for example, the thickness of each layer is generally 5-50 microns, and the aluminum substrate 110 is generally 0.1-3.0 mm. If the drawings in the specification are made according to the actual scale, there will be a problem of unclear illustration. Therefore, in order to more clearly represent the implementation process of the manufacturing method, the drawings of the present embodiment are all enlarged schematic diagrams of the technical features, which do not represent the size of the actual structure diagram, nor represent the enlarged diagram of the actual structure diagram in the same proportion.

[0081] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation made under the inventive concept of the present application, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.

Claims

1. A method for manufacturing a high-heat-dissipation aluminum-based multilayer rigid-flex plate, characterized in that, The manufacturing method includes the following steps: S10: The structure of the multilayer rigid-flex board is split into a first copper layer and a multilayer flexible core board layer. An aluminum substrate and a first adhesive layer are taken, and the first adhesive layer and the first copper layer are sequentially attached to the surface of the aluminum substrate and pressed together to form an aluminum-based copper-clad laminate. S20: A copper layer circuit pattern is formed on the first copper layer of the aluminum-based copper-clad laminate, and an aluminum substrate through hole is formed, the aluminum substrate through hole including an aluminum substrate pin hole. Then, an aluminum substrate window area is formed to form a windowed aluminum substrate. S30: Fabricate the core layer of the multilayer flexible board according to a predetermined process, and form the surface pattern layer of the core layer; Take the second adhesive layer and attach it to the core board layer; Then, the first cover film is taken, a first cover film pattern is made to form a first cover film layer, and the first cover film layer is attached to the surface of the second adhesive layer. The first cover film layer corresponds to the window area of ​​the aluminum substrate. The entire structure is formed into a flexible cover film; A through-hole is made in the flexible cover film, the through-hole including a pin hole in the flexible core board; The entire process forms a flexible adhesive-coated board; S40: Take the second covering film, and make a second covering film pattern to form a second covering film layer, wherein the second covering film pattern includes covering film pin holes; The second covering film, the flexible adhesive plate, and the windowed aluminum substrate are stacked sequentially from bottom to top and placed in a pressing device for whole-plate pressing. The whole-plate pressing also includes: An airbag is fabricated, wherein the airbag is a structure with an air-filled interior sealed plastic layer, and the airbag is placed on the upper surface of the pressing equipment. A pressing mold is made, and the surface of the pressing mold is provided with pins. The pressing mold is then placed on the lower table surface of the pressing equipment. The stacked arrangement from bottom to top includes: The cover film pin holes, the flexible core board pin holes, and the aluminum substrate pin holes are sequentially fitted onto the pins from bottom to top. The entire assembly is formed into a press-fit plate; The forming of the press plate also includes: Take the third adhesive layer and make an adhesive layer window area, the adhesive layer window area corresponding to the first cover film layer, and make an adhesive layer through hole, the adhesive layer through hole including an adhesive layer pin hole; The entire structure forms a windowed adhesive layer; The stacked arrangement from bottom to top includes: The pin holes of the cover film, the pin holes of the flexible core board, the pin holes of the adhesive layer, and the pin holes of the aluminum substrate are sequentially fitted onto the pins from bottom to top. S50: The press plate is electroplated and back-drilled to form the aluminum-based multilayer rigid-flex plate. Before electroplating the press plate, it is necessary to drill holes in the press plate. The drilling is carried out according to the drilling pattern of the aluminum-based multilayer rigid-flex plate. The back-drilling process refers to back-drilling the through holes in the aluminum substrate.

2. The method for manufacturing a high heat dissipation aluminum-based multilayer rigid-flex plate as described in claim 1, characterized in that, After the windowed area of ​​the aluminum substrate is made, a browning process is performed.

3. The method for manufacturing a high heat dissipation aluminum-based multilayer rigid-flex plate as described in claim 1, characterized in that, After drilling, the press plate is subjected to laser ablation, plasma treatment, and alkaline washing treatment in sequence. The laser ablation is performed on the stepped position between the windowed area of ​​the aluminum substrate and the first covering film layer.

4. The method for manufacturing a high heat dissipation aluminum-based multilayer rigid-flex plate as described in claim 1, characterized in that, The size of the windowed area on the aluminum substrate is smaller on one side than the size of the first cover film layer.

5. The method for manufacturing a high heat dissipation aluminum-based multilayer rigid-flex plate as described in claim 1, characterized in that, The pressing equipment is a rigid plate press; The parameters for the whole plate pressing are as follows: heating rate of 2°C / min to 6°C / min, maximum temperature of 160°C to 180°C, and pressure of 15 kg / cm². 2 Up to 25kg / cm 2 The cooling rate is 10℃ / minute to 20℃ / minute.

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