A method for plugging and grinding a copper-clad plate with a recessed portion

Abstract

The invention discloses a plugging and grinding method for a copper-clad plate with a concave portion, comprising the following steps: preparation, taking a copper-clad plate, the copper-clad plate comprising a flat plate portion and a concave portion, both of which are provided with plugging holes; applying a dry film, applying a dry film on the surface of the copper-clad plate, and providing a window on the dry film; plugging the holes with resin, and then baking and curing the resin normally after plugging the holes with resin; first grinding, grinding off the resin layer on the flat plate portion with a ceramic grinding plate to expose the dry film, while the dry film in the concave portion is not exposed; stripping, placing the entire copper-clad plate in a stripping liquid to dissolve the dry film, exposing the resin piles on the flat plate portion, and after the dry film in the concave portion is dissolved, a gap exists between the resin layer on the concave portion and the inner bottom surface of the concave portion; decomposition, wiping the resin layer on the concave portion with a decomposition liquid to decompose it, until the resin layer on the concave portion is decomposed and the resin piles in the concave are exposed; second grinding, grinding off the resin piles in the flat plate portion and the concave portion with a ceramic grinding plate.

Description

Technical Field

[0001] The invention relates to the technical field of circuit boards, and in particular to a method for plugging and grinding a copper-clad plate with a concave portion. Background Art

[0002] Some copper clad laminates will have concave parts during lamination production. When the resin is plugged into the holes of these copper clad laminates, the concave parts will be filled with resin. In the subsequent ceramic grinding process, the resin in the concave parts cannot be ground away, affecting subsequent production and product yield. Summary of the Invention

[0003] 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 plugging and grinding a copper-clad laminate having a recessed portion, which can prevent the recessed portion of the copper-clad laminate from being filled with a large area of ​​resin, facilitate subsequent production, and improve product yield.

[0004] According to a first aspect of the present invention, a method for plugging and grinding a copper-clad laminate having a recessed portion includes the following steps:

[0005] Preparation: Take a copper clad laminate that has been laminated but not plugged with resin, the copper clad laminate comprising a flat portion and a recessed portion, both the flat portion and the recessed portion being provided with plugged holes;

[0006] Laying a dry film: Laying a dry film on the surface of the copper clad laminate, the dry film covering the flat portion and the recessed portion, and providing a window on the dry film at a position corresponding to the hole opening of the plug hole;

[0007] Resin plugging: After the resin plugging is used, the resin is normally baked and cured, and the resin forms a resin layer on the surface of the dry film;

[0008] During the first grinding, the resin layer on the flat plate is ground off by a ceramic grinding plate to expose the dry film, while the resin layer in the concave portion is not completely ground off, and the dry film in the concave portion is not exposed;

[0009] Stripping the film, placing the entire copper clad laminate into a stripping solution to dissolve the dry film, exposing the resin piles on the flat portion. After the dry film in the concave portion is dissolved, the resin layer on the concave portion is supported by the resin piles in the concave portion, and a gap exists between the resin layer on the concave portion and the inner bottom surface of the concave portion.

[0010] Decomposition, wiping the resin layer on the recessed portion with a decomposition liquid to decompose it, until the resin layer on the recessed portion is decomposed and the resin pile in the recessed portion is exposed;

[0011] The second grinding process is to grind away the resin piles in the flat plate portion and the concave portion by using a ceramic grinding plate.

[0012] A plugging and grinding method for a copper-clad laminate having a recess according to an embodiment of the present invention has at least the following beneficial effects: since the dry film isolation protection is provided between the copper-clad laminate and the resin layer in the recess, the resin layer on the recess will separate from the inner bottom surface of the recess as the dry film decomposes, and the copper-clad laminate will not be worn during the second grinding, resulting in a reduction in copper thickness. In addition, resin residue in the recess can be avoided to a limited extent, thereby improving product yield and facilitating subsequent production.

[0013] According to some embodiments of the present invention, in the step of applying the dry film, the thickness of the dry film is less than or equal to 3 mils. The thickness setting facilitates the rapid decomposition of the dry film and improves production efficiency.

[0014] According to some embodiments of the present invention, the radius of the window opening is 2 mil or more larger than the radius of the plug hole. The radius of the window opening being larger than the radius of the plug hole facilitates guiding the resin into the plug hole, making the resin in the plug hole fuller.

[0015] According to some embodiments of the present invention, in the resin plugging step, resin is first injected into the plugging hole from the open window, and then the fluid resin is repeatedly brushed on the copper clad laminate with a brush, and the resin in the plugging hole is compacted by the brush to avoid the formation of cavities.

[0016] According to some embodiments of the present invention, in the dry film pasting step, the dry film is first spread flat on the copper clad board, and then the dry film on the recess is pressed into the recess tightly to avoid a gap between the dry film and the recess. When the resin is plugging the hole, the dry film sinks and cracks, causing the resin to enter the recess.

[0017] According to some embodiments of the present invention, in the dry film pasting step, the dry film is exposed and developed after pasting to find the window.

[0018] According to some embodiments of the present invention, in the first grinding step, the dry film in the recess needs to be ground until a portion is exposed, and the exposed portion is convenient for contact with the decomposition liquid, thereby facilitating the decomposition of the dry film in the recess.

[0019] According to some embodiments of the present invention, in the film stripping step, the copper clad laminate needs to be shaken in the film stripping solution to discharge the deposited dry film debris.

[0020] 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

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0022] Figure 1 This is a schematic diagram of a copper clad laminate after dry film plugging is provided in an embodiment of the present invention;

[0023] Figure 2 for Figure 1 The structural schematic diagram of the copper clad plate shown;

[0024] Figure 3 for Figure 1 Schematic diagram of the structure of the copper clad laminate combined with the dry film;

[0025] Figure 4 for Figure 1 The schematic diagram of the structure of removing dry film after plugging holes in a copper clad laminate is shown;

[0026] Figure 5 for Figure 1 The schematic diagram of the structure of the copper clad laminate is shown in which the dry film is removed and then the resin layer on the concave portion is removed.

[0027] Copper clad plate 100, flat plate part 110, recessed part 120, plug hole 130;

[0028] Dry film 200, window 210;

[0029] Resin layer 300 and resin pile 310 . DETAILED DESCRIPTION

[0030] 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.

[0031] 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.

[0032] In the description of the present invention, "several" means one or more, "more" means two or more, "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.

[0033] 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.

[0034] Reference Figures 1 to 5 A method for plugging and grinding a copper-clad plate having a concave portion comprises the following steps:

[0035] Preparation: Take a copper clad laminate 100 that has been laminated but not plugged with resin. The copper clad laminate 100 includes a flat portion 110 and a recessed portion 120. Both the flat portion 110 and the recessed portion 120 are provided with plugged holes 130.

[0036] A dry film is applied on the surface of the copper clad laminate 100. The dry film 200 covers the flat portion 110 and the recessed portion 120. A window 210 is provided on the dry film 200 at the position corresponding to the opening of the plug hole 130.

[0037] Resin plugging: After the resin plugging is applied, the resin is normally baked and cured, and the resin forms a resin layer 300 on the surface of the dry film 200;

[0038] During the first grinding, the ceramic grinding plate is used to grind away the resin layer 300 on the flat portion 110 to expose the dry film 200 . However, the resin layer 300 in the concave portion 120 is not completely ground away, and the dry film 200 in the concave portion 120 is not exposed.

[0039] Film stripping: Place the entire copper clad laminate 100 in a film stripping solution to dissolve the dry film 200, exposing the resin piles 310 on the flat portion 110. After the dry film 200 in the recessed portion 120 is dissolved, the resin layer 300 on the recessed portion 120 is supported by the resin piles 310 in the recessed portion 120, leaving a gap between the resin layer 300 on the recessed portion 120 and the inner bottom surface of the recessed portion 120.

[0040] Decomposition: Wipe the resin layer 300 on the concave portion 120 with a decomposition liquid to decompose it until the resin layer 300 on the concave portion 120 is decomposed to expose the resin pile 310 in the concave portion 120;

[0041] During the second grinding process, the resin piles 310 in the flat plate portion 110 and the recessed portion 120 are ground away by the ceramic grinding plate.

[0042] Since the dry film 200 is provided for isolation and protection between the copper clad laminate 100 and the resin layer 300 in the recess 120, the resin layer 300 on the recess 120 will separate from the inner bottom surface of the recess 120 as the dry film 200 decomposes. During the second grinding, the copper clad laminate 100 will not be worn away, thereby reducing the copper thickness. In addition, resin residue in the recess 120 can be avoided to a limited extent, thereby improving product yield and facilitating subsequent production.

[0043] It should be noted that because the resin in the recess 120 is difficult to remove, there are currently three solutions to this problem. One solution is to use a blocking mesh to plug the resin, but for products with a large number of holes and dense hole positions, the blocking mesh cannot be exposed to the sun, so it cannot completely solve the problem; another solution is to manually wipe the residual resin in the recess 120 with alcohol after plugging the resin, but for products with a design that requires plugging holes 130 in the recess 120, using this solution will cause the resin at the hole mouth to be decomposed and precipitated by alcohol, and this solution is still not advisable; the third solution is to manually use sandpaper to polish the residual resin in the recess 120 after using a ceramic grinding plate, but due to poor manual operation stability, the surface copper thickness uniformity of the product after manual polishing cannot meet the processing requirements, so this solution still has limitations, so dry film 200 is used for isolation to prevent the recess 120 from being stained with resin, and it is also convenient to clean up later.

[0044] In some embodiments, during the dry film application step, the thickness of the dry film 200 is less than or equal to 3 mils. The thickness setting facilitates rapid decomposition of the dry film and improves production efficiency.

[0045] In some embodiments, the radius of the window 210 is 2 mil or more larger than the radius of the plug hole 130. The radius of the window 210 is larger than the radius of the plug hole 130 to facilitate guiding the resin into the plug hole 130, so that the resin in the plug hole 130 is fuller.

[0046] In some embodiments, in the resin plugging step, the resin is first injected into the plugging hole 130 from the window 210, and then the fluid resin is repeatedly brushed on the copper clad laminate 100 with a brush. The brush is used to compact the resin in the plugging hole 130 to avoid the formation of cavities. The fluid resin is a physical state of the resin.

[0047] In some embodiments, in the dry film pasting step, the dry film 200 is first spread flat on the copper clad laminate 100, and then the dry film 200 on the recess 120 is pressed tightly into the recess 120 to avoid a gap between the dry film 200 and the recess 120. When the resin is plugging the hole, the dry film 200 sinks and cracks, causing the resin to enter the recess 120.

[0048] In some embodiments, in the dry film pasting step, the dry film is exposed and developed after pasting to find the opening 210 .

[0049] In some embodiments, in the first grinding step, the dry film 200 in the recess 120 needs to be partially exposed. The exposed portion is convenient for contact with the decomposition liquid, which is beneficial for decomposing the dry film 200 in the recess 120 .

[0050] In some embodiments, during the film stripping step, the copper clad laminate 100 needs to be shaken in the film stripping solution to remove debris from the deposited dry film 200 .

[0051] It is not limited by the number of holes or the density of holes in the plugging product; and the entire solution does not require manual intervention, with high reliability, applicability and effectiveness.

[0052] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. A method for plugging and grinding a copper-clad plate having a concave portion, characterized in that: The following steps are involved: Preparation: Take a copper clad board (100) that has been laminated but not plugged with resin, the copper clad board (100) comprising a flat plate portion (110) and a recessed portion (120), and both the flat plate portion (110) and the recessed portion (120) are provided with plugged holes (130); A dry film is applied, wherein a dry film (200) is applied to the surface of the copper clad plate (100), the dry film (200) covers the flat plate portion (110) and the recessed portion (120), and a window (210) is provided on the dry film (200) at a position corresponding to the opening of the plug hole (130); Resin plugging, after plugging the holes with resin, the resin is normally baked and solidified, and the resin forms a resin layer (300) on the surface of the dry film (200); During the first grinding, the resin layer (300) on the flat plate (110) is ground off by a ceramic grinding plate to expose the dry film (200), while the resin layer (300) in the concave portion (120) is not completely ground off, and the dry film (200) in the concave portion (120) is not exposed; Stripping the film, placing the entire copper clad laminate (100) into a stripping solution to dissolve the dry film (200), exposing the resin piles (310) on the flat portion (110), and after the dry film (200) in the recess (120) is dissolved, the resin layer (300) on the recess (120) is supported by the resin piles (310) in the recess (120), and a gap exists between the resin layer (300) on the recess (120) and the inner bottom surface of the recess (120); Decomposition: wiping the resin layer (300) on the concave portion (120) with a decomposition liquid to decompose it, until the resin layer (300) on the concave portion (120) is decomposed to expose the resin pile (310) in the concave portion (120); The second grinding process is to grind away the resin piles (310) in the flat plate portion (110) and the recessed portion (120) by means of a ceramic grinding plate.

2. The method for plugging and grinding a copper-clad laminate having a recess according to claim 1, wherein: In the step of applying the dry film, the thickness of the dry film (200) is less than or equal to 3 mil.

3. The method for plugging and grinding a copper-clad laminate having a recess according to claim 1, wherein: The radius of the window (210) is greater than or equal to 2 mils than the radius of the plug hole (130).

4. The method for plugging and grinding a copper-clad laminate having a recess according to claim 1, wherein: In the resin plugging step, resin is first injected into the plugging hole (130) from the window (210), and then the fluid resin is repeatedly brushed on the copper clad board (100) with a brush, and the resin in the plugging hole (130) is compacted by the brush to avoid the formation of cavities.

5. The method for plugging and grinding a copper-clad laminate having a recess according to claim 1, wherein: In the dry film pasting step, the dry film (200) is first spread flat on the copper clad laminate (100), and then the dry film (200) on the recess (120) is pressed into the recess (120) to adhere tightly.

6. The method for plugging and grinding a copper-clad laminate having a recess according to claim 1, wherein: In the dry film pasting step, after the dry film is pasted, it is exposed and developed to find the opening (210).

7. The method for plugging and grinding a copper-clad laminate having a recess according to claim 1, wherein: In the first grinding step, the dry film (200) in the recess (120) needs to be ground until a portion thereof is exposed.

8. The method for plugging and grinding a copper-clad laminate having a recess according to claim 1, wherein: In the film stripping step, the copper clad plate (100) needs to be shaken in the film stripping solution to discharge the deposited dry film (200) debris.

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