Circuit board and manufacturing method thereof

Abstract

The invention discloses a circuit board and a manufacturing method thereof. The polyimide reinforcing plate is attached to the glue-resisting adhesive tape to form the combined adhesive tape, the thickness and hardness of the glue-resisting medium are increased, the problems of excessive glue flowing and poor cover opening are reduced, the combined adhesive tape is provided with the handle, and the combined adhesive tape is dragged out through the handle. According to the method, the damage to glass fibers of the hard core board and the bonding sheet is reduced, the risk of core board breakage is reduced, so that the uncovering production efficiency and the product quality are improved, a plurality of mother boards can be uncovered together through the combined adhesive tape, rapid uncovering is achieved, and compared with a conventional adhesive tape glue blocking process, the uncovering efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of printed circuit boards, and in particular to a circuit board and a manufacturing method thereof. Background Art

[0002] A rigid-flex board is a circuit board that has both FPC and circuit board characteristics by combining a flexible circuit board and a rigid circuit board through lamination and other processes according to relevant process requirements.

[0003] At present, the manufacturing process of the soft board area of ​​the traditional rigid-flex board mainly adopts the conventional adhesive tape blocking protection process or the low-flow adhesive sheet window protection process. In the adhesive tape blocking protection process, due to the thin thickness and small size of the adhesive tape itself, it is difficult to achieve the bonding and positioning during the bonding process with the narrow width soft board area; during the opening process, the prying operation of the narrow soft board area will cause the hard board core board and the glass fiber structure in the adhesive sheet to be subjected to concentrated stress, and then break, which not only reduces production efficiency but also affects product quality. In the low-flow adhesive sheet window protection process, due to the narrow width structure of the soft board area, during the high-temperature and high-pressure pressing process, excessive glue flow is likely to occur after pressing; at the same time, during the subsequent opening operation, the prying operation of the narrow soft board area will cause the hard board core board to break, which cannot meet the high-quality and high-efficiency production requirements. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a method for manufacturing a circuit board, which can reduce the problems of excessive glue flow and poor cover opening.

[0005] The present invention also provides a circuit board manufactured using the above manufacturing method.

[0006] A method for manufacturing a circuit board according to a first embodiment of the present invention includes the following steps: Laminating the polyimide reinforcing plate on the adhesive-blocking tape to form a composite tape having a handle; Setting a window area on the bonding sheet; Connecting a plurality of core panels to the bonding sheet and arranging them at intervals along a first direction, and arranging the combined adhesive tape in the window area along a second direction, wherein the combined adhesive tape cooperates with the core panels and the bonding sheet to form a plurality of pressing units, and the plurality of pressing units are arranged at intervals along the second direction, wherein the second direction is perpendicular to the first direction; Pressing the core board and the corresponding bonding sheet together to form a motherboard; cutting off the core plate on the side where the handle is located so as to expose the handle; The combined adhesive tape is dragged out by the handle to form cavity areas in the plurality of motherboards.

[0007] A method for manufacturing a circuit board according to an embodiment of the present invention has at least the following beneficial effects: the present application forms a combined tape by using a polyimide reinforcement plate to bond a glue-blocking tape, thereby increasing the thickness and hardness of the glue-blocking medium and reducing the problems of excessive glue flow and poor cover opening. In addition, the combined tape has a handle, and the combined tape is dragged out by the handle. Compared with the traditional method of directly prying the narrow soft board area to open the cover, the damage to the glass fiber of the hard board core board and the bonding sheet is reduced, and the risk of the core board breaking is reduced, thereby improving the cover opening production efficiency and product quality. In addition, the combined tape can open the covers of multiple motherboards together to achieve rapid cover opening, which improves the cover opening efficiency compared to the conventional tape glue-blocking process. According to some embodiments of the present invention, the combined adhesive tape has a handle, and the manufacturing method further comprises: The combined adhesive tape is processed to form the handle and the base, so that at least one end of the base is connected to the handle; and an inner arc structure is formed at the connection between the handle and the base.

[0008] According to some embodiments of the present invention, the step of connecting the plurality of chips to the bonding sheet and arranging them at intervals along the first direction further comprises: The core board is processed into a soft board and a hard board, the soft board and the hard board are spaced apart along the first direction, and the bonding sheet is arranged between the hard board and the soft board, and the bonding sheet is set to be a low-flow bonding sheet.

[0009] According to some embodiments of the present invention, providing a window area on the bonding sheet includes: The window area is formed by processing the bonding sheet between the hard board and the soft board, and a safety area is set between the window area and the bonding sheet.

[0010] According to some embodiments of the present invention, the step of providing a safety area between the window area and the bonding sheet further comprises: The width of the safety area is set to 0.2 mm to 0.3 mm; The gap between the combined adhesive tape and the edge of the window area is set to 0.2 mm to 0.25 mm.

[0011] According to some embodiments of the present invention, disposing the combined adhesive tape in the window area along the second direction further includes: The thickness of the combined adhesive tape is processed to be greater than the thickness of the bonding sheet.

[0012] According to some embodiments of the present invention, the thickness of the combined adhesive tape is processed to be 0.03 mm to 0.05 mm greater than the thickness of the bonding sheet.

[0013] According to some embodiments of the present invention, the step of connecting the plurality of chips to the bonding sheet and arranging them at intervals along the first direction further comprises: Processing the core board to form a soft board and a copper foil layer, and arranging the copper foil layer on two opposite sides of the soft board along the first direction, and arranging the bonding sheet between the soft board and the copper foil layer; The window area is formed by processing the bonding sheet between the flexible board and the copper foil layer, and a safety area is set between the window area and the bonding sheet.

[0014] According to some embodiments of the present invention, disposing the combined adhesive tape in the window area along the second direction further includes: The thickness of the combined adhesive tape is processed to be smaller than the thickness of the bonding sheet.

[0015] According to some embodiments of the present invention, the cutting of the core plate on the side where the handle is located further comprises: After the core board and the corresponding bonding sheet are pressed together, the combined tape has a remaining layer of dielectric along the first direction and on a side away from the soft board, and the thickness of the remaining layer of dielectric is set to be less than or equal to 0.05 mm.

[0016] The circuit board according to the second embodiment of the present invention is manufactured using the method for manufacturing the circuit board according to the first embodiment.

[0017] The circuit board according to the embodiment of the present invention has at least the following beneficial effects: the circuit board of the present application is manufactured by the circuit board manufacturing method of the above embodiment, which reduces the damage to the glass fiber of the hard board core board and the bonding sheet, thereby improving product quality.

[0018] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which: Figure 1 This is a flow chart of a method for manufacturing a circuit board according to an embodiment of the present invention; Figure 2 This is a schematic diagram of manufacturing a composite tape according to a first embodiment of the present invention; Figure 3 This is a schematic structural diagram of a combined adhesive tape according to a first embodiment of the present invention; Figure 4 This is a schematic structural diagram of a core board according to an embodiment of the present invention; Figure 5 This is a schematic structural diagram of a core plate and an adhesive sheet arranged at intervals according to an embodiment of the present invention; Figure 6 This is another structural schematic diagram of a core plate and an adhesive sheet arranged at intervals according to an embodiment of the present invention; Figure 7 This is a structural schematic diagram of a core board and an adhesive sheet pressed together in accordance with an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure after the hard board is milled through in the first embodiment of the present invention; Figure 9 This is a schematic structural diagram of a composite adhesive tape in a plurality of laminating units according to an embodiment of the present invention; Figure 10 This is a structural diagram of dragging out the combined adhesive tape according to the first embodiment of the present invention; Figure 11 This is a structural diagram of a core board according to embodiment 2 of the present invention; Figure 12 This is a structural diagram of the circuit board manufactured according to the second embodiment of the present invention.

[0020] Figure numerals: 100, combined tape; 110, polyimide reinforcement plate; 120, adhesive tape; 130, base; 140, handle; 150, inner arc structure; 200, bonding sheet; 300, core board; 310, soft board; 320, hard board; 330, copper foil layer; 400, covering film; 500, pressing unit; 600, window area; 700, safety area. DETAILED DESCRIPTION

[0021] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0022] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0023] In the description of the present invention, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0024] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0025] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0026] Example 1 A method for manufacturing a circuit board according to an embodiment of the present application includes the following steps: Reference Figure 1 、 Figure 3 Step S100: Laminating the polyimide reinforcing plate 110 on the adhesive tape 120 to form a combined tape 100 , wherein the combined tape 100 has a handle 140 ; Reference Figure 2 Optionally, laminating the polyimide reinforcing plate 110 to the adhesive-blocking tape 120 further includes: using a pressing roller to compact the polyimide reinforcing plate 110 and the adhesive-blocking tape 120 to form a combined adhesive tape 100, which is then laser cut or molded. Laminating the polyimide reinforcing plate 110 to the adhesive-blocking tape 120 to form the combined adhesive tape 100 increases the thickness and hardness of the adhesive-blocking medium, thereby reducing problems such as excessive adhesive flow and poor cover opening.

[0027] Based on the considerations of balancing the bending and tearing properties of the polyimide material, the thickness of the polyimide reinforcement plate 110 in the composite tape 100 is set to 0.075mm to 0.15mm. This ensures that the composite tape 100 has a certain degree of rigidity to provide support while also having good bending properties, reducing problems such as circuit breakage and insulation damage caused by bending. In addition, the thickness of the adhesive tape 120 is set to 25μm, and the polyimide reinforcement plate 110 is bonded to the tape using an epoxy adhesive system. The epoxy adhesive system has excellent bonding properties and can form a bond between the polyimide reinforcement plate 110 and the adhesive tape 120. This helps to ensure the structural integrity of the composite tape 100 throughout the circuit board manufacturing process and prevents problems such as delamination and debonding under process conditions such as lamination and high temperature.

[0028] Reference Figure 3Optionally, the combined adhesive tape 100 has a handle 140. The circuit board manufacturing method further includes: processing the combined adhesive tape 100 to form a base 130 and a handle 140, so that at least one end of the base 130 is connected to the handle 140, and forming an inner arc structure 150 at the connection between the handle 140 and the base 130 to enhance the connection strength between the handle 140 and the base 130. Specifically, the handles 140 are connected to both ends of the base 130, and the width of the handles 140 is greater than the width of the base 130, so that the handles 140 and the combined adhesive tape 100 form an "I" shape. During the pulling action of opening the cover, conventional right-angle or acute-angle connection parts are prone to form stress concentration points, and the connection position between the handle 140 and the base 130 is easily torn. Therefore, an inner arc structure 150 is provided at the connection between the handle 140 and the base 130. The inner arc structure 150 makes a smooth transition so that the stress can be evenly dispersed to a larger area, avoiding excessive accumulation of stress at the connection position, thereby reducing the risk of the connection position between the handle 140 and the base 130 being torn, enhancing the stability of the overall structure, and ensuring the integrity of the combined tape 100 during use.

[0029] Reference Figure 3 Optionally, the inner arc angle of the inner arc structure 150 is 45° to 90°, which can ensure the stress dispersion effect without increasing the processing difficulty due to a too small angle. In addition, the length L1 and width L2 of the handle 140 are both 5mm to 6mm, which is convenient for the operator to grasp and apply force, so as to serve as a starting point for opening the lid.

[0030] Reference Figure 1 、 Figure 5 、 Figure 9 Step S200: Setting a window area 600 on the bonding sheet 200. The window area 600 is formed on the bonding sheet 200 to provide clearance for the subsequent placement of the combined adhesive tape 100, allowing the combined adhesive tape 100 to enter the window area 600. During the lamination process, the adhesive flow from the bonding sheet 200 is blocked, preventing the adhesive from overflowing into unwanted areas, thereby preventing the adhesive from contaminating other components or affecting the performance of the circuit board.

[0031] Reference Figure 5 、 Figure 9 Step S300: Connect multiple core boards 300 and bonding sheets 200 and arrange them at intervals along the first direction, and arrange the combined tape 100 in the window area 600 along the second direction. The combined tape 100 cooperates with the core boards 300 and the bonding sheets 200 to form multiple pressing units 500. The multiple pressing units 500 are arranged at intervals along the second direction, and the second direction is perpendicular to the first direction.

[0032] It should be noted that the first direction is the Z direction, and the second direction is the X direction.

[0033] Reference Figure 4 、 Figure 5 In this embodiment, in step S300, specifically, the core board 300 is processed into a soft board 310 and a hard board 320, so that the soft board 310 and the hard board 320 are spaced apart along the first direction, and a bonding sheet 200 is provided between the hard board 320 and the soft board 310, and the bonding sheet 200 is set as a low flow bonding sheet 200. Figure 5 , multiple core boards 300 and bonding sheets 200 are arranged in the order of hard board 320, bonding sheet 200, soft board 310, bonding sheet 200, and hard board 320. The bonding sheet 200 can combine the soft board 310 with the hard board 320 to form a soft-hard bonding area and a bending area.

[0034] Reference Figure 7 It should be noted that, in this embodiment, covering films 400 are provided on both sides of the flexible board 310 that are opposite to each other along the first direction, and a composite tape 100 is provided on the side of each covering film 400 away from the flexible board 310, which can ensure that the flowing glue will not pass through the composite tape 100 and flow to the covering film 400, thereby blocking the flowing glue.

[0035] Reference Figure 1 、 Figure 5 、 Figure 9 In this embodiment, in step S300, multiple core boards 300 are connected to the bonding sheet 200 and are arranged at intervals along the first direction, and the combined tape 100 is arranged in the window area 600 along the second direction. The combined tape 100 cooperates with the core board 300 and the bonding sheet 200 to form a plurality of pressing units 500. The plurality of pressing units 500 are arranged at intervals along the second direction. By placing a combined tape 100 in the window area 600 of multiple pressing units 500 at the same time, one combined tape 100 is used instead of multiple tapes to improve production efficiency.

[0036] In this embodiment, in step S300, the window area 600 is provided on the bonding sheet 200. This includes processing the bonding sheet 200 between the rigid board 320 and the flexible board 310 to form the window area 600, and providing a safety area 700 between the window area 600 and the bonding sheet 200. The safety area 700 compensates for adhesive flow from the bonding sheet 200, preventing adhesive flow from the bonding sheet 200 from reaching the edge of the composite tape 100 during subsequent lamination.

[0037] Of course, in some other embodiments, in step S300, the soft board 310 is provided in plurality, the hard board 320 is provided in plurality, and the bonding sheet 200 is provided between the soft boards 310, and the bonding sheet 200 is provided between the soft boards 310 and the hard boards 320. Figure 6A plurality of core boards 300 and corresponding bonding sheets 200 are arranged in the order of hard board 320, bonding sheet 200, soft board 310, bonding sheet 200, soft board 310, bonding sheet 200, and hard board 320 to form a pressing unit 500. The bonding sheet 200 can combine the soft board 310 with the hard board 320 to form two soft-hard bonding areas and a bending area. The bending area is located in the middle of the two soft-hard bonding areas.

[0038] Reference Figure 5 In this embodiment, since the thickness of the combined tape 100 is increased and the polyimide material does not contain glass fiber, it will not break after opening the cover. Therefore, the width D of the combined tape 100 is designed to be ≥ 1.5 mm. Compared with conventional tapes, the manufacturing capability of the width of the soft board area of ​​the soft-rigid combination board is improved, and the minimum width of the soft board area is reduced from 3 mm to 1.5 mm.

[0039] Reference Figure 2 、 Figure 5 In this embodiment, the width of the window area 600 is designed to be A, and the adhesive sheet 200 is set to a low-flow adhesive sheet 200. Based on the consideration that the glue flow of the low-flow adhesive sheet 200 is 1.0 to 1.5 mm, the width D1 of the safety area 700 is set to 0.2 mm to 0.3 mm to ensure that during the lamination process, the glue of the low-flow adhesive sheet 200 can fully fill the required area to ensure that no lamination voids occur. In addition, the polyimide reinforcement plate 110 is bonded to the adhesive resistance tape 120. Based on the bonding error between the polyimide reinforcement plate 110 and the adhesive resistance tape 120, the gap D2 between the combined tape 100 and the edge of the window area 600 is set to 0.2 mm to 0.25 mm to prevent the combined tape 100 from being attached to the bonding area. It should be noted that the edge of the window area 600 is referenced Figure 5 The dotted line B in .

[0040] Reference Figure 5 In this embodiment, in step S300, in order to make the combined tape 100 act as a glue barrier and to ensure that the position of the combined tape 100 does not protrude too much after lamination, the thickness H of the combined tape 100 is processed to be greater than the thickness H1 of the bonding sheet 200, and the thickness of the combined tape 100 is 0.03mm to 0.05mm greater than the thickness of the bonding sheet 200, that is, 0.03mm≤H-H1≤0.05mm, to prevent the combined tape 100 from protruding too high, causing the substrate to leak after the circuit board is polished. For example, if the thickness of the bonding sheet 200 is set to 0.15mm, the thickness of the combined tape 100 is between 0.18mm and 0.2mm. In addition, by making the combined tape 100 thicker than the bonding sheet 200 and using a low-flow bonding sheet 200, the glue flowing after lamination is blocked by the combined tape 100, so as to achieve the effect of no glue flowing on the combined tape 100.

[0041] Reference Figure 1 、 Figure 7 Step S400: Laminating the core boards 300 and the corresponding bonding sheets 200 to form a motherboard. Multiple core boards 300 and bonding sheets 200 arranged in a sequentially spaced arrangement are laminated. During the lamination process, the composite adhesive tape 100 can cooperate to prevent adhesive flow from the bonding sheets 200. After lamination is completed, the motherboard is obtained.

[0042] In this embodiment, in step S400 , after the core board 300 and the corresponding bonding sheet 200 are pressed together to form a motherboard, the process further includes drilling, electroplating, pattern transfer, solder mask, surface treatment and the like.

[0043] Reference Figure 1 、 Figure 8 、 Figure 9 Step S500: Cut away the core plate 300 on the side where the handle 140 is located, exposing the handle 140 and facilitating the removal of the assembly tape 100 through the handle 140, thereby opening the cover. Specifically, the hard plate 320 on the side where the handle 140 is located is cut away. Because the hard plate 320 and the assembly tape 100 are of different colors, the hard plate 320 is milled through during the depth control process. When the dark brown color of the assembly tape 100 is visible, it can be determined that the depth control depth has reached the target depth.

[0044] Reference Figure 1 、 Figure 8 In this embodiment, in step S500, the core plate 300 on the side where the handle 140 is located is removed. After the core plate 300 and the corresponding bonding sheet 200 are pressed together, a remaining layer of dielectric remains on the side of the composite tape 100 along the first direction and away from the flexible board 310. The thickness H2 of the remaining dielectric is set to be less than or equal to 0.05 mm. When the dielectric thickness within the cavity area is equal to the thickness of the core plate 300 and the bonding sheet 200, after controlled depth opening, the thickness of the remaining dielectric layer extending to the composite tape 100 is H2. By reducing the thickness of the composite tape 100 along the first direction and away from the flexible board 310, the presence of glass fibers from the core plate 300 or the bonding sheet 200 on the composite tape 100 is avoided, the resistance to opening the cover is reduced, and subsequent opening is facilitated.

[0045] Reference Figure 2 、 Figure 9 、 Figure 10Step S600: Use handle 140 to drag the combined tape 100 outward, forming cavities within the multiple motherboards. Because the remaining dielectric layer within the cavities is at most 0.05 mm thick, and a safety zone 700 is provided between the window area 600 of the adhesive sheet 200 and the adhesive sheet 200, the adhesive sheets 200 on both sides of the combined tape 100 are pre-compensated for the window openings before lamination. After lamination, only the adhesive flow from the adhesive sheet 200 contacts the sidewalls of the combined tape 100, resulting in less resistance during opening. By utilizing the bending and tearing resistance of the polyimide reinforcement plate 110, the cavities of multiple motherboards can be opened simultaneously, thereby improving opening efficiency.

[0046] The present application forms a combined tape 100 by using a polyimide reinforcing plate 110 to bond the adhesive tape 120, thereby increasing the thickness and hardness of the adhesive blocking medium and reducing the problems of excessive adhesive flow and poor opening. In addition, the combined tape 100 has a handle 140. By dragging the combined tape 100 out through the handle 140, compared with the traditional method of directly prying the narrow soft board 310 area to open the cover, the damage to the glass fiber of the hard board 320 core board 300 and the bonding sheet 200 is reduced, and the risk of the core board 300 breaking is reduced, thereby improving the production efficiency of opening the cover and the quality of the product. In addition, the combined tape 100 can open the covers of multiple motherboards together to achieve rapid opening, which improves the opening efficiency compared to the conventional tape adhesive blocking process.

[0047] A printed circuit board according to a second embodiment of the present invention is manufactured using the circuit board manufacturing method of the first embodiment described above. The circuit board of the present application, manufactured using the circuit board manufacturing method of the above embodiment, reduces damage to the glass fibers of the rigid board 320, the core board 300, and the bonding sheet 200, thereby improving product quality.

[0048] Example 2 Different from the first embodiment, in step S300, a plurality of core boards 300 are connected to the bonding sheet 200 and arranged at intervals along the first direction, the core boards 300 are processed to form a soft board 310 and a copper foil layer 330, and the copper foil layer 330 is arranged on two opposite sides of the soft board 310 along the first direction, and a bonding sheet 200 is arranged between the soft board 310 and the copper foil layer 330. The bonding sheet 200 is a common bonding sheet 200 with large glue flow. Specifically, refer to Figure 11 Multiple core boards 300 and corresponding bonding sheets 200 are arranged in sequence of copper foil layer 330, bonding sheet 200, soft board 310, bonding sheet 200, and copper foil layer 330. The core boards 300, bonding sheet 200 and combined tape 100 cooperate to form a pressing unit 500.

[0049] In step S300, a window region 600 is formed on the bonding sheet 200 between the flexible circuit board 310 and the copper foil layer 330. This window region 600 allows the assembly tape 100 to enter the window region 600, preventing adhesive flow from the bonding sheet 200 during the lamination process. Furthermore, a safety region 700 is provided between the window region 600 and the bonding sheet 200 to compensate for adhesive flow from the bonding sheet 200. This prevents adhesive flow from the bonding sheet 200 from reaching the edges of the assembly tape 100 during subsequent lamination.

[0050] Reference Figure 12 , different from the first embodiment, in step S300, the composite tape 100 is arranged in the window area 600 along the second direction, and the thickness H of the composite tape 100 is processed to be smaller than the thickness H1 of the bonding sheet 200, and the thickness of the composite tape 100 is 0.125mm to 0.15mm smaller than the thickness of the bonding sheet 200, that is, 0.03mm≤H1-H≤0.05mm, so that the glue flow through the bonding sheet 200 after lamination will not be blocked, and the glue flow will bond the copper foil layer 330 and the composite tape 100 into a whole.

[0051] What is different from the first embodiment is that in step S400, after the core board 300 and the corresponding adhesive sheet 200 are pressed together to form a motherboard, the copper foil layer 330 in the cavity area is also etched. Since there is only glue flowing on the composite tape 100 and the thickness is ≤0.05mm, there is no need for mechanical depth control or laser depth control after etching. It is only necessary to rely on the inherent hardness of the polyimide reinforcement plate 110 in the composite tape 100 to control the depth of the handle 140 position and use the handle 140 to tear off the media on the cavity area of ​​multiple motherboards. The opening method of this embodiment is simple and efficient, does not require silk screen ink, and can also achieve the effect of blocking glue. At the same time, no mechanical or laser depth control is required when opening the cover, and it can be applied to soft-hard combination board products with thin media.

[0052] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. A method for manufacturing a circuit board, characterized in that: The following steps are involved: Laminating the polyimide reinforcing plate on the adhesive-blocking tape to form a composite tape having a handle; Setting a window area on the bonding sheet; Connecting a plurality of core panels to the bonding sheet and arranging them at intervals along a first direction, and arranging the combined adhesive tape in the window area along a second direction, wherein the combined adhesive tape cooperates with the core panels and the bonding sheet to form a plurality of pressing units, and the plurality of pressing units are arranged at intervals along the second direction, wherein the second direction is perpendicular to the first direction; Pressing the core board and the corresponding bonding sheet together to form a motherboard; cutting off the core plate on the side where the handle is located so as to expose the handle; The combined adhesive tape is dragged out by the handle to form cavity areas in the plurality of motherboards.

2. The method for manufacturing a circuit board according to claim 1, wherein: The combined adhesive tape has a handle, and the manufacturing method further comprises: The combined adhesive tape is processed to form the handle and the base, so that at least one end of the base is connected to the handle; and an inner arc structure is formed at the connection between the handle and the base.

3. The method for manufacturing a circuit board according to claim 1, wherein: The method of connecting the plurality of chips to the bonding sheet and arranging them at intervals along the first direction further comprises: The core board is processed into a soft board and a hard board, the soft board and the hard board are spaced apart along the first direction, and the bonding sheet is arranged between the hard board and the soft board, and the bonding sheet is set to be a low-flow bonding sheet.

4. The method for manufacturing a circuit board according to claim 3, wherein: The step of providing a window area on the bonding sheet includes: The window area is formed by processing the bonding sheet between the hard board and the soft board, and a safety area is set between the window area and the bonding sheet.

5. The method for manufacturing a circuit board according to claim 4, wherein: The safety area is provided between the window area and the bonding sheet, further comprising: The width of the safety area is set to 0.2 mm to 0.3 mm; The gap between the combined adhesive tape and the edge of the window area is set to 0.2 mm to 0.25 mm.

6. The method for manufacturing a circuit board according to claim 3, wherein: The step of placing the combined adhesive tape in the window area along the second direction further comprises: The thickness of the combined adhesive tape is processed to be greater than the thickness of the bonding sheet.

7. The method for manufacturing a circuit board according to claim 1, wherein: The method of connecting the plurality of chips to the bonding sheet and arranging them at intervals along the first direction further comprises: Processing the core board to form a soft board and a copper foil layer, and arranging the copper foil layer on two opposite sides of the soft board along the first direction, and arranging the bonding sheet between the soft board and the copper foil layer; The window area is formed by processing the bonding sheet between the flexible board and the copper foil layer, and a safety area is set between the window area and the bonding sheet.

8. The method for manufacturing a circuit board according to claim 7, wherein: The step of placing the combined adhesive tape in the window area along the second direction further comprises: The thickness of the combined adhesive tape is processed to be smaller than the thickness of the bonding sheet.

9. The method for manufacturing a circuit board according to claim 3 or 7, wherein: The step of cutting off the core plate on the side where the handle is located further comprises: After the core board and the corresponding bonding sheet are pressed together, the combined tape has a remaining layer of dielectric along the first direction and on a side away from the soft board, and the thickness of the remaining layer of dielectric is set to be less than or equal to 0.05 mm.

10. A circuit board, characterized in that: The circuit board is manufactured using the method for manufacturing the circuit board according to any one of claims 1 to 9.

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