A multilayer wiring board manufacturing method, device, and apparatus

Abstract

This invention belongs to the technical field of circuit board manufacturing processes, and particularly relates to a method, apparatus, and equipment for manufacturing multilayer circuit boards. The invention proposes a method for manufacturing multilayer circuit boards, including: sequentially stacking and pressing multiple first circuit boards into a first circuit board assembly; drilling first through-holes in the first circuit board assembly and filling the first through-holes with resin; stacking second circuit boards on both sides of the first circuit board assembly and pressing them into a second circuit board assembly; drilling second through-holes at the positions of the first through-holes on each layer of the second circuit board, and electroplating copper into the second through-holes. By channeling the heat from the blind vias inside the circuit board through the aligned second through-holes, heat accumulation inside the blind vias is avoided.

Description

Technical Field

[0001] This invention belongs to the technical field of circuit board manufacturing processes, and particularly relates to a method, apparatus and equipment for manufacturing multilayer circuit boards. Background Technology

[0002] The key change that AI computing power demands bring to PCBs is driving their continuous evolution towards high-density interconnects, ultra-high multilayer architecture, and high-speed signal transmission with lower loss and higher bandwidth.

[0003] To meet the demands of AI chips (such as GPUs, ASICs, and HBMs) for more I / O interfaces, smaller pin pitches, and higher integration, high-density interconnects on PCBs are evolving towards higher layer counts, greater thickness, finer line widths / spacings, smaller microvias, and greater plating depth ratios. This aims to achieve a higher number of signal and power connections per unit area, supporting the continuous improvement of computing power and bandwidth. This also leads to higher heat dissipation requirements for high-power chips and devices under high-speed transmission. In existing technologies, AI computing chips require multiple blind vias to allow different layers to be connected. However, AI computing boards have many layers, and the heat dissipation and heat conduction effects of the internal blind vias are not good, which can cause heat to accumulate inside the AI ​​computing board and lead to damage to the AI ​​computing board. Summary of the Invention

[0004] To address the issue of "unsatisfactory heat dissipation and heat conduction effects of the through-holes inside the multi-layer AI computing board, leading to heat accumulation inside the AI ​​computing board," this invention proposes a method, apparatus, and device for manufacturing multi-layer circuit boards.

[0005] The present invention solves the above problems through the following technical solution: In a first aspect, the present invention proposes a method for manufacturing a multilayer circuit board, comprising: The multi-layered first circuit boards are stacked and pressed together to form a first circuit board assembly; Drill a first through hole in the first circuit board assembly and fill the first through hole with resin; The second circuit board is stacked on both sides of the first circuit board assembly and pressed to form the second circuit board assembly; Drill a second through hole at the position of the first through hole on each layer of the second circuit board, and electroplate copper into the second through hole.

[0006] This invention proposes a method for manufacturing multilayer circuit boards, including: sequentially stacking and pressing multiple first circuit boards into a first circuit board assembly; drilling first through holes in the first circuit board assembly and filling the first through holes with resin; stacking second circuit boards on both sides of the first circuit board assembly and pressing them into a second circuit board assembly; drilling second through holes at the positions of the first through holes on each layer of the second circuit board, and electroplating copper into the second through holes. By channeling the heat from the blind vias inside the circuit board through the aligned second through holes, heat accumulation inside the blind vias is avoided.

[0007] In some embodiments, multiple first circuit boards are sequentially stacked and pressed to form a first circuit board assembly; including: Create a circuit pattern on the first circuit board, and set multiple first drill holes in the non-circuit area of ​​the first circuit board.

[0008] In some embodiments, a first through-hole is drilled in the first circuit board assembly, and the first through-hole is filled with resin; including: Laser drilling is performed on multiple adjacent first boreholes to form a first through hole; The first copper plating is performed on both sides of the first circuit board assembly and the inner wall of the first through hole; The first through hole is filled with resin, and the two sides of the first circuit board assembly are plated with copper a second time. Create circuit patterns on both sides of the first circuit board assembly.

[0009] In some embodiments, a second circuit board is stacked on both sides of a first circuit board assembly and pressed to form a second circuit board assembly; including: Create circuit patterns on the second circuit boards on both sides, and set multiple second drill holes at the positions of the first through holes on the second circuit boards.

[0010] In some embodiments, a second through-hole is drilled at the position of the first through-hole on each layer of the second circuit board, and copper is electroplated into the second through-hole; including: A drilling area is set at the position of the first through hole on the second circuit board of each layer; A second borehole is arrayed within the borehole area; Multiple second boreholes are laser-drilled to form second through holes; Fill the second through hole with copper.

[0011] In some embodiments, laser drilling is performed on multiple second boreholes to form second through holes; including: Multiple second boreholes are laser-drilled to form second through holes; Connect adjacent second through holes to form a through groove; Fill the through slot with copper.

[0012] In some implementations... The surface of the through groove is first copper plated; A second copper plating is applied to the drilled area.

[0013] In some implementations, it also includes: Drill a third through hole in the second circuit board assembly; The first copper plating is performed on both sides of the second circuit board assembly and the inner wall of the third through hole; The third through hole is filled with resin, and the two sides of the second circuit board assembly are copper plated a second time. Create circuit patterns on both sides of the second circuit board assembly.

[0014] Secondly, the present invention provides a circuit board manufacturing apparatus, comprising: The first circuit board pressing module is used to press multiple layers of first circuit boards into a first circuit board assembly. The first drilling module is used to drill a first through hole in the first circuit board assembly and fill the first through hole with resin. The second circuit board pressing module is used to stack the second circuit board on both sides of the first circuit board assembly and press it into the second circuit board assembly. The second drilling module is used to drill second through holes at the positions of the first through holes on each layer of the second circuit board, and to electroplate copper into the second through holes.

[0015] Thirdly, the present invention provides a circuit board manufacturing apparatus, comprising the circuit board manufacturing device proposed in the first aspect, wherein the circuit board manufacturing device stores at least one execution instruction, such that the execution instruction, when the circuit board manufacturing device is running, performs a multilayer circuit board production method as described in any of the second aspects.

[0016] The beneficial effects of the multilayer circuit board fabrication method, apparatus, and equipment proposed in this invention are: The multilayer circuit board fabrication method includes: sequentially stacking and pressing multiple first circuit boards to form a first circuit board assembly; drilling first through holes in the first circuit board assembly and filling the first through holes with resin; stacking second circuit boards on both sides of the first circuit board assembly and pressing them to form a second circuit board assembly; drilling second through holes at the positions of the first through holes on each layer of the second circuit board, and electroplating copper into the second through holes. By channeling the heat from the blind vias inside the circuit board through the aligned second through holes, heat accumulation inside the blind vias is avoided.

[0017] The above description is merely an overview of the technical solutions of the embodiments of the present invention. In order to better understand the technical means of the embodiments of the present invention and to implement them in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the embodiments of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0018] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a flowchart of the multilayer circuit board manufacturing method of the present invention; Figure 2 This is a side view of the circuit board in the multilayer circuit board manufacturing method of the present invention; Figure 3 This is a flowchart of step 200 of the multilayer circuit board fabrication method of the present invention; Figure 4 This is a flowchart of step 400 of the multilayer circuit board manufacturing method of the present invention; Figure 5 This is a top view of the drilling area proposed in Embodiment 1 of the multilayer circuit board manufacturing method of the present invention; Figure 6 This is a side view of the second through hole proposed in Embodiment 1 of the multilayer circuit board manufacturing method of the present invention; Figure 7 This is a top view of the second through hole proposed in Embodiment 1 of the multilayer circuit board manufacturing method of the present invention; Figure 8 This is a flowchart of step 430 of the multilayer circuit board manufacturing method of the present invention; Figure 9 This is a side view of the second through hole proposed in Embodiment 2 of the multilayer circuit board manufacturing method of the present invention; Figure 10 This is a top view of the second through hole proposed in Embodiment 2 of the multilayer circuit board manufacturing method of the present invention; Figure 11 This is a flowchart of step 500 of the multilayer circuit board manufacturing method of the present invention; Figure 12 This is a frame diagram of the circuit board manufacturing equipment of the present invention.

[0019] Figure label: 1. First through hole; 2. Second through hole; 3. Drilling area. Detailed Implementation

[0020] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0021] Example 1: like Figures 1-7 As shown, this embodiment proposes a method for fabricating a multilayer circuit board, including: Step 100: Stack and press the multi-layer first circuit boards sequentially to form a first circuit board assembly; Specifically, taking the L24 layer board as an example, the intermediate layer with blind vias is first laminated. For example, the L7-L18 layers are cut into the working size in the factory to complete the material cutting, and the inner layer circuit pattern of each layer is drawn. The L7-L18 layers are then laminated to form the first circuit board assembly.

[0022] Step 200: Drill a first through hole in the first circuit board assembly and fill the first through hole with resin; Specifically, a first through-hole is drilled in the first circuit board assembly of layers L7-L18, and resin is filled into the first through-hole to form a blind via. Further, before filling, copper is plated on the sidewalls and the opening of the first through-hole to improve the overall heat dissipation capacity of the first through-hole. After copper plating, the via is filled with resin to plug it.

[0023] Step 300: Stack the second circuit board on both sides of the first circuit board assembly and press them together to form the second circuit board assembly; Specifically, this step is performed multiple times, namely L6-L19, L5-L20, L4-L21, L3-L22, L2-L23, and L1-L24. By stacking these layers on both sides, the L24 layer circuit board is fabricated. This method allows for the unlimited stacking of second circuit boards, thus creating circuit boards with even more layers.

[0024] Step 400: Drill a second through hole at the position of the first through hole on each layer of the second circuit board, and electroplate copper into the second through hole.

[0025] Specifically, during each stacking of both sides, a second through hole must be drilled at the position of the first through hole on the second circuit board. The second through holes on each layer are usually aligned and filled with copper so that heat can be dissipated outward through the second through holes.

[0026] In some embodiments, multilayer first circuit boards are sequentially stacked and pressed into a first circuit board assembly; including: Create a circuit pattern on the first circuit board, and set multiple first drill holes in the non-circuit area of ​​the first circuit board.

[0027] Specifically, the circuit pattern is created on the first circuit board, that is, after setting the required pattern in the L7-L18 layers, the first drill hole is set in the non-circuit area of ​​the first circuit board. The first drill hole is in the non-circuit area of ​​the first circuit board, and the first drill hole is usually set in a matrix. When drilling, the first through hole is opened by connecting multiple first drill holes, which can reduce the instantaneous stress on the circuit board and further improve the heat dissipation of the circuit board itself. More specifically, the first drill hole is a laser hole.

[0028] In some embodiments, drilling a first through-hole in a first circuit board assembly and filling the first through-hole with resin includes: Step 210: Perform laser drilling on multiple adjacent first boreholes to form a first through hole; Specifically, multiple adjacent first holes are laser-drilled to connect them and form a first through hole. This method avoids damage to the circuit board caused by instantaneous stress. Furthermore, in addition to laser drilling, mechanical drilling is also performed at specific locations on the circuit board. Step 220: Perform the first copper plating on both sides of the first circuit board assembly and the inner wall of the first through hole; Specifically, plasma descaling and electroplating are performed on the first through hole and both sides of the first circuit board assembly after drilling, so that copper is plated inside the hole, thereby improving conductivity and heat dissipation.

[0029] Step 230: Fill the first through hole with resin and perform a second copper plating on both sides of the first circuit board assembly; Specifically, resin is filled into the first through-hole to improve the reliability of the circuit board while protecting it. A second copper plating is then performed on both sides of the first circuit board assembly. This second copper plating allows copper to be deposited on the resin surface of other first through-holes and blind holes, increasing the copper area and improving heat dissipation.

[0030] Step 240: Create circuit patterns on both sides of the first circuit board assembly.

[0031] Specifically, after the copper plating is completed, circuit patterns are created on both sides of the first circuit board assembly.

[0032] In some embodiments, stacking a second circuit board on both sides of a first circuit board assembly and pressing it into a second circuit board assembly includes: Create circuit patterns on the second circuit boards on both sides, and set multiple second drill holes at the positions of the first through holes on the second circuit boards.

[0033] Specifically, the circuit patterns of the second circuit boards on both sides are further fabricated, and multiple second drill holes are set at the positions of the first through holes on the second circuit boards so that multiple blind holes are formed after laser drilling, thereby improving the overall heat dissipation capacity.

[0034] In some embodiments, a second through hole is drilled at the position of the first through hole on each layer of the second circuit board, and copper is electroplated into the second through hole; including: Step 410: Set the drilling area for the position of the first through hole on each layer of the second circuit board; Specifically, a drilling area is set at the position of the first through-hole on each layer of the second circuit board. The drilling area can be marked with ink on its periphery to improve the efficiency of visual addressing by the laser equipment. The size of the drilling area is larger than the required size of the first through-hole, and the center of the first through-hole is set within the drilling area.

[0035] Step 420: Set up a second borehole in the array within the borehole area; Specifically, multiple second drill holes can be set in the drilled area, such as nine second drill holes in a 3×3 pattern. This method can further improve the heat dissipation intensity in the drilled area. Furthermore, this method can avoid setting multiple second drill holes, thus avoiding the weakening of the circuit board strength caused by multiple drill holes.

[0036] Step 430: Perform laser drilling on multiple second boreholes to form second through holes; Specifically, by setting up a second borehole using a matrix, after multiple second through holes are formed by laser drilling, the multiple second through holes can enhance the heat dissipation intensity of the first through hole in the drilling area.

[0037] Step 440: Fill the second through hole with copper.

[0038] Specifically, copper is filled into the second through hole to improve heat conduction and dissipation.

[0039] Example 2: like Figures 8-9 This embodiment further optimizes and explains the multilayer circuit board fabrication method proposed in Embodiment 1: In some embodiments, laser drilling is performed on a plurality of second boreholes to form a second through hole; including: Step 431: Perform laser drilling on multiple second boreholes to form second through holes; Specifically, multiple second boreholes are laser drilled to form independent second through holes; Step 432: Connect adjacent second through holes to form a through groove; Specifically, adjacent second through holes are connected to form through slots. For example, nine holes in a 3×3 grid within the drilling area can be connected laterally or longitudinally to form multiple rows or columns of through slots. Optionally, both lateral and longitudinal connections can be made simultaneously, which can further improve heat dissipation but will reduce the strength within the drilling area.

[0040] Step 433: Fill the through slot with copper.

[0041] Specifically, by filling the through slot with copper, the copper plating can fill the entire through slot, thereby further improving the heat dissipation capacity.

[0042] In some embodiments, the surface of the through-slot is first copper plated; the drilled area is then copper plated a second time. Specifically, by first copper plating the surface of the through-slot and then further copper plating the drilled area, the copper thickness above the first through-hole can be increased, thereby increasing the heat dissipation capacity of the first through-hole.

[0043] In some implementations, it also includes: Step 510: Drill a third through hole in the second circuit board assembly; Specifically, a third through hole is drilled into the second circuit board assembly, and the third through hole runs through all the circuit boards.

[0044] Step 520: Perform the first copper plating on both sides of the second circuit board assembly and the inner wall of the third through hole; the heat dissipation and heat conduction capabilities of the circuit board are further improved through the third through hole.

[0045] Specifically, copper plating is performed on both sides of the second circuit board assembly and the inner wall of the third through hole. The first copper plating can form a copper layer on the inner wall, thereby improving the heat dissipation capacity of the third through hole.

[0046] Step 530: Fill the third through hole with resin and perform a second copper plating on both sides of the second circuit board assembly; Specifically, resin is filled into the third through hole to enhance the strength of the overall circuit board, and copper is plated a second time on both sides of the second circuit board assembly so that the copper can cover both ends of the resin.

[0047] Step 540: Create circuit patterns on both sides of the second circuit board assembly.

[0048] Specifically, by creating circuit diagrams, the circuit diagrams on both sides of the surface can be created.

[0049] Example 3: like Figure 10 As shown, this embodiment proposes a circuit board manufacturing apparatus, including a first circuit board lamination module 610, a first drilling module 620, a second circuit board lamination module 630, and a second drilling module 640: The first circuit board pressing module 610 is used to perform step 100, thereby stacking and pressing multiple layers of first circuit boards into a first circuit board assembly. The first drilling module 620 is used to perform step 200, so that the first drilling module 620 drills a first through hole in the first circuit board assembly after being pressed by the first circuit board pressing module 610, and fills the first through hole with resin. The second circuit board pressing module 630 is used to perform step 300. The second circuit board pressing module 630 is used to stack the second circuit board on both sides of the first circuit board assembly made by the first drilling module 620 and press it into the second circuit board assembly. The second drilling module 640 is used to perform step 400. The second drilling module 640 is used to drill a second through hole at the position of the first through hole on each layer of the second circuit board, and to electroplate copper into the second through hole.

[0050] Example 4: The present invention provides a circuit board manufacturing apparatus, including the circuit board manufacturing device proposed in the first aspect. The circuit board manufacturing device stores at least one execution instruction, such that the execution instruction performs the multilayer circuit board production method as described in Embodiment 1 and / or Embodiment 2 when the circuit board manufacturing device is running.

[0051] Specifically, at least the circuit board manufacturing equipment includes a circuit board laminating device, a circuit board pattern making device, a circuit board drilling device, and a circuit board copper plating device. The circuit board laminating device is used to press multiple circuit boards into a circuit board assembly, the circuit board pattern making device is used to make circuit patterns on the inner and outer layers of the circuit board, the circuit board drilling device is used to perform laser and mechanical drilling on the circuit board, and the circuit board copper plating device is used to apply copper plating to the through holes and surface of the circuit board.

[0052] The circuit board manufacturing equipment can be a production line formed by multiple devices. The circuit board manufacturing equipment includes at least one controller, which is equipped with at least one execution instruction. The execution instruction is used to execute the multilayer circuit board production method as described in either Example 1 or Example 2.

[0053] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. Similarly, for the sake of brevity and to aid in understanding one or more aspects of the invention, in the description of exemplary embodiments of the invention above, various features of the embodiments are sometimes grouped together in a single embodiment, figure, or description thereof. The claims, which follow the detailed description, are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0054] Those skilled in the art will understand that the modules in the device of the embodiment can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiment can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components, except that at least some of such features and / or processes or units are mutually exclusive.

[0055] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be construed as limiting the order of execution.

Claims

1. A method for manufacturing a multilayer circuit board, characterized in that, include: The multi-layered first circuit boards are stacked and pressed together to form a first circuit board assembly; Drill a first through hole in the first circuit board assembly and fill the first through hole with resin; The second circuit board is stacked on both sides of the first circuit board assembly and pressed to form the second circuit board assembly; Drill a second through hole at the position of the first through hole on each layer of the second circuit board, and electroplate copper into the second through hole.

2. The method for manufacturing a multilayer circuit board according to claim 1, characterized in that, The step of sequentially stacking and pressing multiple layers of first circuit boards into a first circuit board assembly includes: A circuit pattern is created on the first circuit board, and multiple first drill holes are set in the non-circuit area of ​​the first circuit board.

3. The method for manufacturing multilayer circuit boards according to claim 2, characterized in that, The step of drilling a first through hole in the first circuit board assembly and filling the first through hole with resin includes: The first through hole is formed by laser drilling multiple adjacent first holes; The first copper plating is performed on both sides of the first circuit board assembly and the inner sidewall of the first through hole. The first through hole is filled with resin, and the two sides of the first circuit board assembly are plated with copper a second time. Create circuit patterns on both sides of the first circuit board assembly.

4. The method for manufacturing a multilayer circuit board according to claim 1, characterized in that, The step of stacking the second circuit board on both sides of the first circuit board assembly and pressing it into a second circuit board assembly includes: The circuit patterns are fabricated on the second circuit boards on both sides, and multiple second drill holes are set at the positions of the first through holes on the second circuit boards.

5. The method for manufacturing a multilayer circuit board according to claim 4, characterized in that, Drilling a second through hole at the position of the first through hole on each layer of the second circuit board, and electroplating copper into the second through hole; includes: A drilling area is set at the position of the first through hole on each layer of the second circuit board; A second borehole is arrayed within the borehole area; Laser drilling is performed on multiple second boreholes to form the second through hole; The second through hole is filled with copper.

6. The method for manufacturing a multilayer circuit board according to claim 5, characterized in that, The second through hole is formed by laser drilling of multiple second boreholes; include: Laser drilling is performed on multiple second boreholes to form the second through hole; Connect adjacent second through holes to form a through groove; The through-slot is filled with copper.

7. The method for manufacturing a multilayer circuit board according to claim 6, characterized in that, The surface of the through groove is first copper plated; A second copper plating is performed on the drilled area.

8. The method for manufacturing a multilayer circuit board according to claim 1, characterized in that, Also includes: Drill a third through hole in the second circuit board assembly; The second circuit board assembly and the inner wall of the third through hole are first copper plated. The third through hole is filled with resin, and the two sides of the second circuit board assembly are copper plated a second time. Create circuit patterns on both sides of the second circuit board assembly.

9. A circuit board manufacturing apparatus, characterized in that, include: The first circuit board pressing module is used to press multiple layers of first circuit boards into a first circuit board assembly. The first drilling module is used to drill a first through hole in the first circuit board assembly and fill the first through hole with resin. The second circuit board pressing module is used to stack the second circuit board on both sides of the first circuit board assembly and press it into the second circuit board assembly. The second drilling module is used to drill a second through hole at the position of the first through hole on each layer of the second circuit board, and to electroplate copper into the second through hole.

10. A circuit board manufacturing equipment, characterized in that, The circuit board manufacturing apparatus as described in claim 9 is further comprising storing at least one execution instruction such that the execution instruction performs the multilayer circuit board manufacturing method as described in any one of claims 1-8 when the circuit board manufacturing apparatus is in operation.

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