An inner layer plate for improving the thickness uniformity of a press

Abstract

The utility model relates to an inner layer board that improves the thickness uniformity of pressing, including the inner layer combination board of rectangle, four edges of inner layer combination board all are provided with the glue flow area, four glue flow areas constitute a ring area in common, the glue flow area includes a plurality of regular polygonal glue flow grooves, adjacent glue flow groves are connected and share groove edge, and the top angle of glue flow groove is provided with the circular buffer groove, the utility model discloses through the design of glue flow area and glue flow groove, makes the resin glue flow of circuit board in the pressing process can diffuse along four edges evenly, forms pressure gradient compensation mechanism, effectively eliminates the thickness fluctuation of traditional inner layer board edge because of the difference of glue flow resistance, and the grid layout of regular polygonal glue flow groove can accurately control the glue filling path, cooperates the stress dispersion effect of circular buffer groove, and the resin glue flow is convenient, and the storage is advantageous to further improve the overall board thickness uniformity of circuit board.

Description

Technical Field

[0001] This utility model relates to the field of circuit boards, and more specifically, to an inner layer board that improves the uniformity of lamination thickness. Background Technology

[0002] In the manufacturing process of circuit boards, inner core boards, prepregs, and copper foil are typically pre-stacked and then bonded together at high temperatures to form a multilayer board. Prepregs, usually made of resin, change from a solid to a viscous flow state during bonding and begin to flow. This allows them to fill the gaps between inner core boards and the tiny gaps between the copper foil and the inner circuit boards, ensuring tight contact between the layers. The uniformity of resin flow directly affects the overall thickness uniformity of the multilayer board. In related technologies, several rectangular, slender flow channels are created along the board edges to improve the flow effect. However, in actual production, it has been found that these flow channels have limited effect on improving flow uniformity, typically only meeting thickness variations of around 0.08 mm, and failing to meet more stringent thickness variation quality requirements. Utility Model Content

[0003] In view of this, the present invention provides an inner layer plate that improves the uniformity of the pressed thickness.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] An inner layer plate for improving the uniformity of lamination thickness includes a rectangular inner layer composite plate. Each of the four sides of the inner layer composite plate is provided with a glue flow area, and the four glue flow areas together form an annular area. Each glue flow area includes a plurality of regular polygonal glue flow grooves. Adjacent glue flow grooves are connected to each other and share groove edges, and a circular buffer groove is provided at the top corner of each glue flow groove.

[0006] In the above technical solution, the design of the resin flow area and resin flow channel allows the resin flow of the circuit board to spread evenly along the four sides during the lamination process, forming a pressure gradient compensation mechanism. This effectively eliminates the thickness fluctuation caused by the difference in resin flow resistance at the edges of the traditional inner layer board. The grid layout of the regular polygonal resin flow channel can precisely control the resin filling path. Combined with the stress dispersion effect of the circular buffer groove, it facilitates the flow and storage of resin flow, which is conducive to further improving the overall thickness uniformity of the circuit board and can control the thickness difference within 0.04mm.

[0007] Optionally, in one possible implementation, the inner layer composite plate is a rectangular structure, and a plurality of rectangular SET units are provided in the annular area of ​​the inner layer composite plate, with the plurality of SET units spaced apart.

[0008] In the above technical solution, multiple SET units are designed simultaneously within an inner layer composite board, which can effectively improve the processing efficiency of the circuit board. That is, multiple identical single boards can be formed simultaneously through one processing. Furthermore, since the entire panel is pressed during the lamination process, the resin flows throughout the entire panel area. Therefore, when the boards are subsequently divided into single boards, the thickness difference of the single boards will be significantly reduced.

[0009] Optionally, in one possible implementation, the SET unit is configured as a first array and a second array; wherein the first array includes a plurality of SET units arranged in a rectangular array, the length direction of the SET units in the first array being parallel to the width direction of the inner layer composite plate; the second array includes a plurality of SET units arranged on opposite sides of the first array, the length direction of the SET units in the second array being parallel to the length direction of the inner layer composite plate.

[0010] In the above technical solution, when the design pattern inside the board is consistent, due to the influence of resin flow, the position in the middle of the board is theoretically thicker than the position at the edge of the board after lamination. When both the inner layer combination board and the SET unit are rectangular, on the one hand, arranging multiple SET units in the first array and the second array can increase the space inside the inner layer combination board to maximize the number of SET units; on the other hand, the arrangement of SET units in the first array and the second array can also effectively reduce the position span of the finished board of the same SET unit, thereby effectively reducing the thickness of the finished board of the same SET unit and improving the consistency of its thickness in the length direction.

[0011] Optionally, in one possible implementation, the SET units in the first array are arranged sequentially along the length of the inner layer composite board, and the SET units in the second array are located on opposite sides of the STE unit arrangement direction in the first array.

[0012] In the above technical solution, the arrangement of SET units in the first array and the second array can make full use of the space of the inner layer composite board. The first array spans the entire length of the inner layer composite board, and the second array fills the remaining blank space of the inner layer composite board, so as to maximize the use of the internal space of the inner layer composite board.

[0013] Alternatively, in one possible implementation, the regular polygon is any one of a triangle, rectangle, regular hexagon, or rhombus.

[0014] In the above technical solution, triangles, rectangles, regular hexagons or rhombuses can be spliced ​​into a continuous resin flow network, so that the resin can flow evenly in the resin flow network. This not only helps to improve the uniformity of PP thickness, but also helps to release the internal stress of the board after lamination and improve the warping of the finished board.

[0015] Optionally, in one possible implementation, the distance between the center of the circular buffer groove and the apex of the glue flow groove is less than 0.1 mm.

[0016] In the above technical solution, the circular edge of the circular buffer groove can weaken the right-angle turbulence of the resin flow, and the center of the circular buffer groove can completely coincide with the apex corner of the resin flow groove, or the distance between the two can be controlled within 0.1mm, so as to facilitate the processing of the resin flow area.

[0017] Alternatively, in one possible implementation, the diameter of the circular buffer groove is 1.2-1.5 times the width of the glue flow groove.

[0018] In the above technical solution, the diameter of the circular buffer tank is larger than the width of the glue flow tank, so that the circular buffer tank forms a "pressure buffer chamber". By increasing the volume of glue in the tank, it effectively absorbs the transient pressure fluctuations of glue flow during the pressing process, reduces the uneven glue flow caused by pressure impact, and can also prolong the residence time of glue in the top corner area, promoting the full escape of air bubbles in the glue.

[0019] Alternatively, in one possible implementation, the bottom of the glue-dispensing groove is an arc-shaped transition surface, and the depth of the glue-dispensing groove gradually increases from the inside to the outside of the annular region.

[0020] In the above technical solution, the arc-shaped transition surface at the bottom of the groove can eliminate the fluid retention effect in the right-angle region. By reducing the flow resistance of the adhesive, the adhesive can form a smooth laminar flow in the flow groove. It can also disperse the local stress generated by the curing shrinkage of the adhesive during the pressing process. The design of different groove depths can increase the flow rate of the resin.

[0021] Alternatively, in one possible implementation, all four flow zones are rectangular in structure and have the same width.

[0022] In the above technical solution, the uniform width rectangular flow area, through standardized groove width design, can effectively improve the consistency of resin flow resistance in the four areas, reduce flow rate fluctuations caused by groove width differences, and ensure the uniformity of dielectric thickness in each area of ​​the multilayer PCB. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of one embodiment.

[0025] Figure 2 for Figure 1 Enlarged view of part A in the middle.

[0026] Figure 3 This is a schematic diagram of the layout of the SET unit in one embodiment.

[0027] Reference numerals: 1-Inner layer composite board; 11-SET unit; 111-First array; 112-Second array; 2-Flowing area; 3-Flowing groove; 31-Circular buffer groove. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0030] Please refer to Figure 1 and Figure 2 This embodiment provides an inner layer plate for improving the uniformity of the pressed thickness, including a rectangular inner layer plate 1. Each of the four sides of the inner layer plate 1 is provided with a glue flow area 2, and the four glue flow areas 2 together form an annular area. The glue flow area 2 includes a plurality of regular polygonal glue flow grooves 3. Adjacent glue flow grooves 3 are connected to each other and share the groove edge, and a circular buffer groove 31 is provided at the top corner of the glue flow groove 3.

[0031] The design of the resin flow zone 2 and the resin flow channel 3 allows the resin to spread evenly along the four sides during the lamination process of the circuit board, forming a pressure gradient compensation mechanism. This effectively eliminates the thickness fluctuations caused by differences in resin flow resistance at the edges of traditional inner layer boards. The grid layout of the regular polygonal resin flow channel 3 can precisely control the resin filling path. Combined with the stress dispersion effect of the circular buffer channel 31, it facilitates the flow and storage of resin, which is beneficial to further improve the overall thickness uniformity of the circuit board. This allows the thickness difference of rigid battery products to meet the 0.04mm range 100%. After trial production, small batch, and mass production verification, the full measurement of circuit board thickness before packaging and shipment can be eliminated, saving one personnel inspection production process and the production cost of stacking and packaging for shipment.

[0032] Please refer to Figure 3 It should be noted that the inner layer composite plate 1 has a rectangular structure, and multiple rectangular SET units 11 are arranged in the annular area of ​​the inner layer composite plate 1, with the multiple SET units 11 arranged at intervals.

[0033] Designing multiple SET units 11 within an inner layer composite board 1 can effectively improve the processing efficiency of the circuit board. That is, multiple identical single boards can be formed simultaneously through one processing. Furthermore, since the entire panel is pressed during the pressing process, the resin flows throughout the entire panel area. Therefore, when the boards are subsequently divided into single boards, the thickness difference of the single boards will be significantly reduced.

[0034] In this embodiment, the SET unit 11 is configured as a first array 111 and a second array 112; wherein, the first array 111 includes a plurality of SET units 11 arranged in a rectangular array, and the length direction of the SET units 11 in the first array 111 is parallel to the width direction of the inner layer composite plate 1; the second array 112 includes a plurality of SET units 11 arranged on opposite sides of the first array 111, and the length direction of the SET units 11 in the second array 112 is parallel to the length direction of the inner layer composite plate 1.

[0035] When the internal design patterns are consistent, due to the influence of resin flow, the parts in the middle of the board are usually theoretically thicker than the parts at the edges after lamination. When both the inner layer composite board 1 and the SET unit 11 are rectangular, on the one hand, arranging multiple SET units 11 in the first array 111 and the second array 112 can increase the space within the inner layer composite board 1, so as to maximize the number of SET units 11; on the other hand, the arrangement of SET units 11 in the first array 111 and the second array 112 can also effectively reduce the position span of the finished board of the same SET unit 11, thereby effectively reducing the thickness of the finished board of the same SET unit 11 and improving the thickness consistency in the length direction.

[0036] Specifically, the SET units 11 in the first array 111 are arranged sequentially along the length of the inner layer composite plate 1, and the SET units 11 in the second array 112 are located on opposite sides of the SET units in the first array 111 along the arrangement direction. The SET units 11 in the first array 111 are a rectangular array arranged with the central axis in the width direction of the inner layer composite plate 1 as the center.

[0037] The arrangement of SET units 11 in the first array 111 and the second array 112 can make full use of the space of the inner layer composite board 1. The first array 111 spans the entire length of the inner layer composite board 1, and the second array 112 supplements the remaining blank space of the inner layer composite board 1, so as to maximize the use of the internal space of the inner layer composite board 1.

[0038] In this embodiment, an inner layer composite board 1 with dimensions of 28.4*24.2 inches and SET units 11 with dimensions of 76.2*265 mm are used as examples. The first array 111 is a rectangular array, with multiple SET units 11 arranged in two columns. The two columns of SET units 11 are arranged along the length of the inner layer composite board 1, and are symmetrically arranged about the central axis of the width of the inner layer composite board 1. The second array 112 is configured in two groups, respectively located on opposite sides of the first array 111.

[0039] In this embodiment, the regular polygon can be any one of a triangle, rectangle, regular hexagon, or rhombus. A regular hexagon is preferred in this embodiment, thus forming a honeycomb mesh structure in the glue-flowing channel 3 of the glue-flowing area 2.

[0040] Specifically, triangles, rectangles, regular hexagons, or rhombuses can be pieced together to form a continuous resin flow network, allowing the resin to flow uniformly within the network. This not only helps improve the uniformity of PP thickness during resin flow but also helps release internal stress after lamination, thus reducing warping of the finished board.

[0041] It should be noted that the distance between the center of the circular buffer groove 31 and the apex of the glue flow groove 3 is less than 0.1 mm, and the diameter of the circular buffer groove 31 is 1.2-1.5 times the width of the glue flow groove 3.

[0042] The circular edge of the circular buffer groove 31 can weaken the right-angle turbulence of the resin flow. The center of the circular buffer groove 31 can completely coincide with the apex corner of the resin flow groove 3, or the distance between them can be controlled within 0.1mm to facilitate the processing of the resin flow zone 2. The diameter of the circular buffer groove 31 is larger than the width of the resin flow groove 3, so that the circular buffer groove 31 forms a "pressure buffer chamber". By increasing the volume of the resin in the groove, it effectively absorbs the transient pressure fluctuations of the resin flow during the pressing process, reduces the uneven resin flow caused by pressure impact, and can also prolong the residence time of the resin in the apex area, promoting the full escape of air bubbles in the resin.

[0043] In this embodiment, the bottom of the resin flow tank 3 is an arc-shaped transition surface, and the depth of the resin flow tank 3 gradually increases from the inner side to the outer side of the annular region. The arc-shaped transition surface at the bottom of the tank can eliminate the fluid retention effect in the right-angle region, reduce the flow resistance of the adhesive, and allow the adhesive to form a smooth laminar flow in the resin flow tank 3. It can also disperse the local stress generated by the curing shrinkage of the adhesive during the pressing process, while the design of different tank depths can increase the flow rate of the resin.

[0044] It should be noted that all four flow zones 2 are rectangular in structure, and all four flow zones 2 have the same width. The uniformly wide rectangular flow zones 2, through standardized groove width design, can effectively improve the consistency of resin flow resistance in the four areas, reduce flow rate fluctuations caused by groove width differences, and ensure the uniformity of dielectric thickness in all areas of the multilayer PCB.

[0045] In the description of this utility model, it should be understood that terms such as "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0047] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An inner layer plate for improving the uniformity of pressed thickness, characterized in that, The device includes a rectangular inner layer composite board, with glue-flowing areas on all four sides, and the four glue-flowing areas together form an annular region. Each glue-flowing area includes multiple regular polygonal glue-flowing channels, adjacent glue-flowing channels are connected to each other and share channel edges, and a circular buffer channel is provided at the top corner of each glue-flowing channel.

2. The inner layer plate for improving the uniformity of pressed thickness according to claim 1, characterized in that, The inner layer composite plate has a rectangular structure, and multiple rectangular SET units are arranged in the annular area of ​​the inner layer composite plate, with the multiple SET units spaced apart.

3. The inner layer plate for improving the uniformity of pressed thickness according to claim 2, characterized in that, The SET unit is configured as a first array and a second array; The first array includes multiple SET units arranged in a rectangular array, wherein the length direction of the SET units in the first array is parallel to the width direction of the inner layer composite plate. The second array includes multiple SET units arranged on opposite sides of the first array, wherein the length direction of the SET units in the second array is parallel to the length direction of the inner layer composite plate.

4. The inner layer plate for improving the uniformity of pressed thickness according to claim 3, characterized in that, The SET units in the first array are arranged sequentially along the length of the inner layer composite plate, and the SET units in the second array are located on opposite sides of the STE units in the first array.

5. The inner layer plate for improving the uniformity of pressed thickness according to claim 1, characterized in that, The regular polygon can be any one of a triangle, rectangle, regular hexagon, or rhombus.

6. The inner layer plate for improving the uniformity of pressed thickness according to claim 1, characterized in that, The distance between the center of the circular buffer groove and the apex of the glue flow groove is less than 0.1 mm.

7. The inner layer plate for improving the uniformity of pressed thickness according to claim 6, characterized in that, The diameter of the circular buffer groove is 1.2-1.5 times the width of the glue flow groove.

8. The inner layer plate for improving the uniformity of pressed thickness according to claim 1, characterized in that, The bottom of the glue-dispensing trough is an arc-shaped transition surface, and the depth of the glue-dispensing trough gradually increases from the inside to the outside of the annular region.

9. The inner layer plate for improving the uniformity of pressed thickness according to any one of claims 1-8, characterized in that, All four flow zones are rectangular in structure, and all four flow zones have the same width.

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