Small-spacing PCB (printed circuit board) with selective resin plugging holes

Abstract

The utility model relates to the technical field of PCBs (printed circuit boards), in particular to a small-spacing PCB with selective resin plug holes, which comprises a substrate, at least one plane of the substrate is provided with plug holes and non-plug holes with preset positions and quantity, the plane is further covered with a film, the film is provided with a developing area and a non-developing area, the developing area covers the plug holes, and the non-developing area covers the non-plug holes. And at least part of the non-developing area covers the non-plug hole. According to the utility model, the surface of the substrate is covered with the thin film with the developing area and the non-developing area, so that the developing area in the exposure process is highlighted, the thin film in the hole plugging area is removed, and the thin film in the non-hole plugging area is reserved, thereby solving the problems of resin entering and hole plugging in the small-spacing PCB, simplifying the whole process flow, improving the product yield and quality, and reducing the production cost. And the production cost is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of PCB boards, in particular to a PCB board with selective resin plug holes and small pitch. Background Art

[0002] With the rapid development of the electronics industry, electronic products are entering a stage of multifunctionality and intelligence. In the PCB manufacturing industry, longer process flows lead to longer production cycles, which in turn increases labor and material costs. The production process for conventional resin vias, for example, with a pitch of ≤10mil, includes the following steps: lamination → drilling → deburring → copper plating → electroplating → solder mask pre-treatment → baking → resin vias → curing → ceramic grinding → AOI → secondary drilling → deburring → copper plating → electroplating → post-processing.

[0003] The reason why the aforementioned process is relatively complicated is that when the spacing between plugged holes and non-plugged holes on the PCB board is small (e.g., ≤10 mil), the resin may enter the non-plugged holes at the same time when entering the plugged holes, causing blockage of the holes. During subsequent plug-in and welding, there is a risk of solder penetration and short circuit, which affects the quality of the PCB. For this reason, this application proposes a PCB board with selective resin plugged holes with small spacing to solve the problem of resin entering the non-plugged holes. Utility Model Content

[0004] In order to solve the above technical problems, the utility model provides a PCB board with small pitch selective resin plugging holes. By covering the substrate surface with a film having a developing area and a non-developing area, the developing area is highlighted and distinguished in the exposure process, thereby solving the problem of resin filling in non-plugged holes and blocking holes in small pitch PCB boards.

[0005] The PCB board with selective resin plugging holes and small pitch in this solution includes a substrate, and plugging holes and non-plugging holes are provided with preset positions and numbers on at least one plane of the substrate. The plane is also covered with a film, and the film has a developing area and a non-developing area, wherein the developing area covers the plugging holes, and at least part of the non-developing area covers the non-plugging holes.

[0006] Furthermore, the spacing between the plugged via and the non-plugged via is less than 10 mil.

[0007] Furthermore, the spacing between the plugged via and the non-plugged via is 8 mil.

[0008] Furthermore, the plugged holes and / or non-plugged holes include round holes.

[0009] Furthermore, the thickness of the film is 25 μm.

[0010] Furthermore, the film includes at least one of a polyimide film, a polyester film and a polytetrafluoroethylene film.

[0011] The beneficial effects of the present invention are as follows: the present invention provides a PCB board with a small pitch selectively plugged with resin holes. By covering the substrate surface with a film having a developing area and a non-developing area to highlight and distinguish the developing area in the exposure process, the film in the plugged hole area is removed and the film in the non-plugged hole area is retained, thereby solving the problem of resin entering non-plugged holes and blocking holes in the small-pitch PCB board, simplifying the overall process flow, improving product yield and quality, and effectively reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A top view of a substrate in an embodiment of the present utility model;

[0013] Figure 2 A top view of a film in an embodiment of the present invention;

[0014] Figure 3 This is a top view of a substrate covered with a thin film in an embodiment of the present invention;

[0015] Figure 4 This is a front view of the PCB board in the embodiment of the present utility model;

[0016] Wherein: 10, substrate; 20, plugged hole; 30, non-plugged hole; 40, film; 40a, developed area; 40b, non-developed area. DETAILED DESCRIPTION

[0017] This embodiment provides a PCB board with selective resin plugging holes with small pitch, such as Figure 1 As shown, the substrate 10 is provided with a preset number of plug holes 20 and non-plug holes 30 at a preset position on the surface of the substrate 10. The spacing between the plug holes 20 and the non-plug holes 30 is less than 10 mil. In this embodiment, the spacing is 8 mil. Figure 2 A thin film 40 is covered on the substrate 10, and the thin film 40 has a developing area 40a and a non-developing area 40b, wherein the developing area 40a covers the plug holes 20 and corresponds to the position and number of the plug holes 20, and the other areas are non-developing areas 40b, which are used to cover the non-plug holes 30 and other board surface areas.

[0018] In this embodiment, the areas of the film 40 and the substrate 10 are equal. Figure 3 The figure shows the state after the thin film 40 is covered on the substrate 10 in this embodiment. The non-developing area 40b covers the area outside the plug hole 20. In some other embodiments, the area of ​​the thin film 40 can also be smaller than the board surface, and it is only necessary for the non-developing area 40b to cover the non-plug hole 30.

[0019] like Figure 4 , which is a front view of the PCB board in this embodiment, the film 40 is 25 μm thick and covers the substrate 10 .

[0020] The optimized process of the PCB board resin plug hole spacing of this embodiment is: lamination → drilling → deburring → copper plating → electroplating → film pasting → exposure → development → resin plug hole → curing → film stripping → ceramic grinding plate → AOI → post-process. Compared with the original conventional resin plug hole production process with a spacing of ≤10mil, the secondary drilling, electroplating and copper reduction processes are simplified.

[0021] The specific process of laminating and stripping in this embodiment is as follows:

[0022] A: A film 40 (25 μm thick) is attached to the board surface. An exposure process is used to retain the film on the non-plugged vias 30. The film 40 is removed from the plugged vias 20 through development. Two apertures, plugged vias 20 and non-plugged vias 30, are formed on the board surface.

[0023] B: The lamination temperature is set between 85℃+ / -5℃ (the conventional lamination temperature is between 110℃-130℃);

[0024] C: Set the curing temperature of plug hole 20 to 50℃ and pre-bake for 90 minutes to ensure that the resin is solidified and the dry film is not baked;

[0025] D: After pre-baking, the film is withdrawn at a speed of 2m / min;

[0026] E: Re-curing, the temperature is set at 150℃*2 hours.

[0027] In this embodiment, a thin film 40 having a developing area 40a and a non-developing area 40b is coated on the surface of the substrate 10 to highlight and distinguish the developing areas in the exposure process. The film in the plugged hole 20 area is removed and the film in the non-plugged hole 30 area is retained to solve the problem of resin plugging the non-plugged hole 30 in a small-pitch PCB board, thereby simplifying the overall process flow, improving product yield, and reducing production costs.

[0028] In addition to the above embodiments, the present invention may also have other implementation methods; any technical solutions formed by equivalent replacement or equivalent transformation fall within the protection scope required by the present invention.

Claims

1. A PCB board with selective resin plug holes and small pitch, comprising a substrate (10), wherein at least one plane of the substrate (10) is provided with plug holes (20) and non-plug holes (30) at preset positions and numbers, characterized in that: The plane is also covered with a thin film (40), wherein the thin film (40) has a developing area (40a) and a non-developing area (40b), wherein the developing area (40a) covers the plug hole (20), and at least part of the non-developing area (40b) covers the non-plug hole (30).

2. The PCB board according to claim 1, characterized in that: The spacing between the plug hole (20) and the non-plug hole (30) is less than 10 mil.

3. The PCB board according to claim 1, characterized in that: The spacing between the plug hole (20) and the non-plug hole (30) is 8 mil.

4. The PCB board according to claim 1, characterized in that: The plugged hole (20) and / or the non-plugged hole (30) comprises a circular hole.

5. The PCB board according to claim 1, characterized in that: The thickness of the film (40) is 25 μm.

6. The PCB board according to claim 1, characterized in that: The film (40) includes at least one of a polyimide film, a polyester film and a polytetrafluoroethylene film.

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