Manufacturing method of non-plugging metalized blind hole

Abstract

The invention discloses a method for manufacturing a non-plugging metalized blind hole, which comprises the following steps of: 1, taking a first daughter board and a second daughter board, drilling a first hole in the second daughter board, sequentially plating a metalized copper layer, a gold plating layer and an additional copper plating layer on the surface of the first hole, and plugging resin; 2, manufacturing a circuit on the second daughter board; 3, laminating the first daughter board, the prepreg and the second daughter board to form a mother board; 4, drilling a second hole in the mother board, performing copper deposition treatment on the second hole, and plating copper on the surface of the mother board; 5, manufacturing a circuit on the mother board; 6, plating tin layers on the surfaces of the mother board and the second hole; 7, alkaline etching and back drilling are carried out on the mother board obtained in the step 6 to remove the resin; 8, performing external light imaging on the mother board obtained in the step 7 to expose the first hole; step 9, carrying out alkaline etching on the mother board obtained in the step 8 until the gold-plated layer in the first hole is exposed; and 10, removing the dry film used for external light imaging in the step 8.

Description

Technical Field

[0001] The invention relates to the technical field of printed circuit board manufacturing, and in particular to a method for manufacturing a non-plugging metalized blind hole. Background Art

[0002] The present invention mainly solves the problem of difficulty in making metallized blind holes without resin plugging. Conventional production cannot avoid the glue of the semi-cured sheet flowing into the hole during lamination, resulting in hole plugging and ultimately making the hole unable to be used for pin insertion. 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 making a non-plugging metalized blind hole, which can prevent the glue of the prepreg from flowing into the hole during lamination.

[0004] A method for manufacturing a non-plugged metalized blind via according to an embodiment of the first aspect of the present invention includes:

[0005] Step 1: Take the first sub-board and the second sub-board, drill a first hole on the second sub-board, plate a metallized copper layer, a gold-plated layer and a copper-plated layer on the surface of the first hole in sequence, and then fill the first hole with resin to form a resin block;

[0006] Step 2: Making a circuit on the second sub-board;

[0007] Step 3: placing a prepreg between the first sub-board and the second sub-board, with the circuit layer of the second sub-board attached to the prepreg, and then laminating the first sub-board, the prepreg and the second sub-board to form a motherboard;

[0008] Step 4: drilling a second hole on the motherboard, performing copper deposition treatment on the second hole to obtain a first copper layer, and simultaneously copper plating the surface of the motherboard to obtain a second copper layer;

[0009] Step 5: Making circuits on both sides of the motherboard by external light imaging;

[0010] Step 6: Plating a tin layer on the surface of the motherboard and the second hole;

[0011] Step 7: alkaline etching is performed on the motherboard obtained in step 6 to etch out the circuit, and the second copper layer at the opening of the first hole is drilled open by back drilling to drill out the resin;

[0012] Step 8: performing external light imaging on the motherboard obtained in step 7 to expose the first hole;

[0013] Step nine: performing alkaline etching on the motherboard obtained in step eight until the gold-plated layer in the first hole is exposed;

[0014] Step 10: Remove the dry film used for external light imaging in step 8.

[0015] A method for making a non-plugging metalized blind hole according to an embodiment of the present invention has at least the following beneficial effects: by sequentially copper plating, gold plating and copper plating treatments on the first hole to protect the copper of the hole wall, it helps to ensure good conductivity and reliable connection of the inner wall of the first hole, and there is no need to overcalculate the corrosion time in the subsequent alkaline etching process, saving costs; copper deposition treatment of the second hole and copper plating on the surface of the motherboard help conductivity; alkaline etching and other processing steps ensure accurate and reliable circuit paths and connections on the circuit board; using resin to fill the holes prevents PP glue from flowing into the holes, and laminating multiple sub-boards to form a motherboard helps to achieve complex circuit layouts and component distributions, thereby improving the functionality and performance of the circuit board; the final step of removing the dry film during circuit making helps to remove the covering layer used to protect specific areas, ensuring the final appearance and function of the circuit board; in general, these steps combined can provide high-quality, reliable and high-performance printed circuit boards suitable for various electronic devices and application requirements.

[0016] According to some embodiments of the present invention, the external light imaging includes exposure, development and etching processes.

[0017] According to some embodiments of the present invention, in step 1, the thickness of the copper-plated layer of the first hole is greater than 150 μm.

[0018] According to some embodiments of the present invention, in step seven, the back-drilled hole diameter is 0.075 mm smaller than the hole diameter of the first hole on one side.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 A schematic diagram of drilling a hole in a second sub-board according to an embodiment of the present invention;

[0022] Figure 2 A schematic diagram of copper plating of a first hole according to an embodiment of the present invention;

[0023] Figure 3 A schematic diagram of gold plating of the first hole or the second hole according to an embodiment of the present invention;

[0024] Figure 4 A schematic diagram of copper plating on the first sub-board or the second sub-board according to an embodiment of the present invention;

[0025] Figure 5 A schematic diagram of a first sub-board or a second sub-board plug resin according to an embodiment of the present invention;

[0026] Figure 6 A schematic diagram of etching a circuit of a first sub-board or a second sub-board according to an embodiment of the present invention;

[0027] Figure 7 A schematic diagram of motherboard lamination according to an embodiment of the present invention;

[0028] Figure 8 A schematic diagram of drilling a motherboard according to an embodiment of the present invention;

[0029] Fig. 9 A schematic diagram of metallization of the second hole of a motherboard according to an embodiment of the present invention;

[0030] Fig.10 It is a schematic diagram of attaching a dry film to a motherboard according to an embodiment of the present invention;

[0031] Fig.11 It is a schematic diagram of copper-tin plating of a motherboard according to an embodiment of the present invention;

[0032] Fig.12 A schematic diagram of motherboard circuit etching according to an embodiment of the present invention;

[0033] Fig.13 A schematic diagram of back drilling of blind vias in a motherboard according to an embodiment of the present invention;

[0034] Fig.14 A schematic diagram of a motherboard film according to an embodiment of the present invention;

[0035] Fig.15 A schematic diagram of motherboard etching according to an embodiment of the present invention;

[0036] Fig.16 FIG. 4 is a schematic diagram of a motherboard film stripping process according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described in detail below, and 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 only used to explain the present invention, and cannot be understood as limiting the invention.

[0038] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and 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, and therefore should not be understood as a limitation on the present invention.

[0039] In the description of the present invention, "several" means one or more, "more" means two or more, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0040] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. 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.

[0041] Reference Figures 1 to 16 , a method for making a non-plugging metalized blind via, comprising:

[0042] Step 1: Take the first sub-board 100 and the second sub-board 200, drill a first hole 210 on the second sub-board 200, plate a metallized copper layer 211, a gold-plated layer 212 and a copper-plated layer 213 on the surface of the first hole 210 in sequence, and then fill the first hole 210 with resin to form a resin block 214;

[0043] Step 2: Making a circuit on the second sub-board 200;

[0044] Step 3: The prepreg 400 is disposed between the first sub-board 100 and the second sub-board 200, the circuit layer of the second sub-board 200 is attached to the prepreg 400, and then the first sub-board 100, the prepreg 400 and the second sub-board 200 are laminated to form the motherboard 300;

[0045] Step 4: Drill a second hole 310 on the motherboard 300, perform copper plating on the second hole 310 to obtain a first copper layer 311, and simultaneously copper plate the surface of the motherboard 300 to obtain a second copper layer 312;

[0046] Step 5: Making circuits on both sides of the motherboard 300 by external light imaging;

[0047] Step 6: Plating a tin layer 313 on the surface of the motherboard 300 and the second hole 310;

[0048] Step 7: alkaline etching is performed on the motherboard 300 obtained in step 6 to etch out the circuit, and the second copper layer 312 at the opening of the first hole 210 is drilled open by back drilling and the resin is drilled out;

[0049] Step 8: Performing external light imaging on the motherboard 300 obtained in step 7 to expose the first hole 210;

[0050] Step nine: alkaline etching is performed on the motherboard 300 obtained in step eight until the gold-plated layer 212 in the first hole 210 is exposed;

[0051] Step 10: Remove the dry film used for external light imaging in step 8.

[0052] By sequentially plating copper, gold and copper plating the first hole 210, it helps to ensure good conductivity and reliable connection of the inner wall of the first hole 210, and there is no need to overcalculate the corrosion time in the subsequent alkaline etching process, saving costs; copper deposition treatment of the second hole 310 and copper plating on the surface of the motherboard 300 helps conductivity; alkaline etching and other processing steps ensure precise and reliable circuit paths and connections on the circuit board; using resin to fill the holes and laminating multiple sub-boards to form the motherboard 300 helps to achieve complex circuit layouts and component distributions, thereby improving the functionality and performance of the circuit board; the final step of removing the dry film during circuit making helps to remove the covering layer used to protect specific areas, ensuring the final appearance and functionality of the circuit board; in general, these steps combine to provide high-quality, reliable and high-performance printed circuit boards suitable for a variety of electronic devices and application requirements.

[0053] In some embodiments, the external light imaging includes exposure, development, and etching processes.

[0054] In some embodiments, in step 1, the thickness of the copper-plated layer 213 of the first hole 210 is greater than 150 μm.

[0055] In some embodiments, in step seven, the back-drilled hole diameter is 0.075 mm smaller than the hole diameter of the first hole 210 .

[0056] In some embodiments, the first hole 210 is made in the inner layer, which reduces the problem of limited copper plating capacity when copper is plated in the hole. The first hole 210 is made in the inner layer and then plugged with resin, which avoids the problem of PP glue entering the hole. The first hole 210 is first plated with gold and then plated with thick copper before plugging the resin in the inner layer, which avoids the problem of back drilling failing to completely drill out the resin in the hole and etching corroding the copper under the gold hole.

[0057] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A method for making a non-plugged metalized blind via, characterized in that: include: Step 1: Take a first sub-board (100) and a second sub-board (200), drill a first hole (210) on the second sub-board (200), plate a metallized copper layer (211), a gold-plated layer (212) and a copper-plated layer (213) on the surface of the first hole (210) in sequence, and then fill the first hole (210) with resin to form a resin block (214); Step 2: making a circuit on the second sub-board (200); Step three: placing a prepreg (400) between the first sub-board (100) and the second sub-board (200), with the circuit layer of the second sub-board (200) attached to the prepreg (400), and then laminating the first sub-board (100), the prepreg (400) and the second sub-board (200) to form a motherboard (300); Step 4: drilling a second hole (310) on the motherboard (300), performing copper deposition treatment on the second hole (310) to obtain a first copper layer (311), and simultaneously copper plating the surface of the motherboard (300) to obtain a second copper layer (312); Step 5: Producing circuits on both sides of the motherboard (300) by external light imaging; Step six: plating a tin layer (313) on the surface of the motherboard (300) and the second hole (310); Step 7: performing alkaline etching on the motherboard (300) obtained in step 6 to etch out the circuit, drilling the second copper layer (312) at the opening of the first hole (210) by back drilling, and drilling out the resin; Step eight: performing external light imaging on the motherboard (300) obtained in step seven to expose the first hole (210); Step nine: performing alkaline etching on the motherboard (300) obtained in step eight until the gold-plated layer (212) in the first hole (210) is exposed; Step 10: Remove the dry film used for outdoor imaging in step 8.

2. The method for making a non-plugged metalized blind via according to claim 1, characterized in that: The external light imaging includes exposure, development and etching processes.

3. The method for manufacturing a non-plugged metalized blind via according to claim 1, characterized in that: In the step 1, the thickness of the copper-plated layer (213) of the first hole (210) is greater than 150 μm.

4. The method for manufacturing a non-plugged metalized blind via according to claim 1, characterized in that: In the step seven, the back-drilled hole diameter is 0.075 mm smaller than the hole diameter of the first hole (210) on one side.

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