CN113179588B

CN113179588B - Manufacturing method of PCB

Info

Publication number: CN113179588B
Application number: CN202110486060.9A
Authority: CN
Inventors: 刘潭武; 王小平; 陈长平; 纪成光
Original assignee: Shengyi Electronics Co Ltd
Current assignee: Shengyi Electronics Co Ltd
Priority date: 2021-04-30
Filing date: 2021-04-30
Publication date: 2022-06-21
Anticipated expiration: 2041-04-30
Also published as: CN113179588A

Abstract

The invention discloses a PCB manufacturing method and a PCB, wherein the manufacturing method comprises the following steps: manufacturing a crimping hole area on the daughter board; adhering a spacer with the copper deposition resistance to completely cover the first surface of the daughter board; performing laser windowing on the spacer to form a first windowing portion on the periphery of the crimping hole area and a second windowing portion at the drilling position of each crimping hole; sequentially stacking a low-flow prepreg and copper foil on the isolating sheet, stacking the low-flow prepreg between the second surfaces of the two daughter boards, and pressing the two daughter boards to obtain a mother board; manufacturing a through hole on the motherboard; removing the copper foil and the spacing sheet to obtain a PCB; according to the invention, the PCB with the flush surface and the smaller thickness can be prepared, the formation of steps on the surfaces of the press-connection hole and the through hole of the PCB due to the low-flow prepreg remained outside the press-connection hole area is effectively avoided, the difficulty of subsequently inserting and installing components on the PCB is effectively reduced, and the user experience is effectively improved.

Description

Manufacturing method of PCB

Technical Field

The invention relates to the technical field of Printed Circuit Boards (PCBs), in particular to a manufacturing method of a PCB.

Background

In the prior art, the asymmetric design of the PCB double-sided crimping holes is mainly manufactured by adopting an N + N double-sided crimping process, the crimping holes are protected by adopting a copper foil and low-flow prepreg mode after a daughter board is pressed into a mother board, and the phenomenon that liquid medicine involved in the manufacture of through holes bites the crimping holes to cause the damage of the crimping holes due to the fact that the liquid medicine involved in the wet process treatment such as liquid medicine biting and biting is avoided when the through holes are manufactured subsequently is avoided.

However, in the prior art, when the daughter board is manufactured, the outer layer copper of the daughter board except the crimping hole area needs to be etched, only the outer layer copper on the crimping hole area of the daughter board is reserved, the position of the low-flow prepreg corresponding to the crimping hole area is windowed, then the low-flow prepreg and the copper foil are integrally laminated on the daughter board according to the stacking sequence, and at the moment, the copper foil is directly laminated into the outer layer of the daughter board except the crimping hole area. After the through hole is manufactured and the copper foil corresponding to the crimping hole area is torn off, the outer layer of the daughter board corresponding to the crimping hole area is exposed, and the part of the daughter board except the crimping hole area has a height difference relative to the outer layer part of the crimping hole area of the daughter board due to the low-flow prepreg between the copper foil and the daughter board, so that a height step is formed between the crimping hole and the through hole, and the PCB manufactured by the prior art has the following defects:

1. the low flow prepreg remaining outside the crimp hole area increases the thickness of the finished PCB;

2. the height step is formed between the crimping hole and the through hole, so that the surface of the PCB is uneven, subsequent insertion and assembly of components on the PCB are not facilitated, and the user experience is seriously influenced.

Disclosure of Invention

The invention aims to provide a PCB manufacturing method and a PCB, which can be used for manufacturing a PCB with a flush surface and a smaller thickness, effectively avoids the formation of high and low steps on the surfaces of a press connection hole and a through hole of the PCB due to the existence of low-flow prepregs outside the press connection hole area, effectively reduces the difficulty of inserting and mounting components on the PCB in the follow-up process, and effectively improves the user experience.

In order to realize the purpose, the invention discloses a manufacturing method of a PCB, which comprises the following steps:

s1, manufacturing at least one crimping hole area on the sub-plate, wherein each crimping hole area is internally provided with at least one crimping hole;

s2, adhering a spacer with the copper deposition resistance and completely covering the first surface of the daughter board;

s3, laser windowing is respectively carried out on the spacers and the low-flow prepregs, so that first windowing parts are formed at the positions, corresponding to the peripheral sides of the crimping hole areas, of the spacers, second windowing parts are formed at the positions, corresponding to the drilling positions of the crimping holes, of the spacers, third windowing parts are formed at the positions, corresponding to the drilling positions of the crimping holes, of the low-flow prepregs, the third windowing parts are formed at the positions, corresponding to the drilling positions of the crimping holes, of the low-flow prepregs, wherein the first windowing parts and the crimping hole areas are concentrically arranged, the crimping hole areas are located in the area defined by the inner edges of the first windowing parts, the second windowing parts and the crimping holes are concentrically arranged, the diameter of the second windowing parts is larger than that of the crimping holes, and the diameter of the third windowing parts is larger than that of the second windowing parts;

s4, sequentially stacking a low-flow prepreg and copper foil on the spacers, oppositely stacking the second surfaces of the two daughter boards, and pressing the two daughter boards to obtain a mother board;

s5, manufacturing at least one through hole on the motherboard;

and S6, removing the copper foil and the spacer to obtain the PCB.

Preferably, the step (5) specifically includes:

s51, drilling the motherboard to form at least one through hole;

and S52, carrying out copper deposition, electroplating treatment and surface treatment on the through hole.

Preferably, in the step (6), removing the copper foil and the spacer specifically includes:

s61, carrying out laser cutting treatment on the copper foil to form a notch on the copper foil;

s62, picking the copper foil from the spacer and removing the copper foil;

and S63, the separation sheet is separated from the daughter board and removed.

Specifically, the copper foil is picked up and removed from the sub-board by using a cutter, and the spacer is picked up and removed from the sub-board by using a ceramic grinding board and/or a cutter.

Preferably, the spacer is a high temperature resistant adhesive tape, an ink layer or a dry film layer with copper deposition resistance.

Preferably, step (1) is preceded by:

s101, manufacturing inner layer patterns of each core board;

s102, performing brown oxidation treatment on each layer of core plate;

and S103, stacking the core plates according to a preset stacking sequence, and then performing plate pressing treatment to obtain the daughter board.

Preferably, a plurality of crimping holes are arranged in the crimping hole area, all the crimping holes in each crimping hole area are distributed in an array to form a rectangular crimping hole area, the first windowing part is in a rectangular ring shape, the distance between the outer edge of the first windowing part and the corresponding edge of the crimping hole area is 9.5 to 10.5Mil, and the diameter of the second windowing part is 2.5 to 3.5Mil larger than the diameter of the crimping holes.

Preferably, the step (1) specifically includes:

s11, drilling in each preset crimping hole area of the daughter board respectively to form at least one crimping hole;

and S12, performing copper deposition, electroplating treatment and surface treatment on the crimping hole.

Preferably, in the step (6), the removing the copper foil and the spacer further includes:

s7, manufacturing an outer layer graph of the motherboard;

and S8, performing green oil treatment, surface treatment and appearance milling treatment on the mother board.

Correspondingly, the invention also discloses a PCB which is manufactured according to the manufacturing method of the PCB.

Compared with the prior art, the method has the advantages that the spacers with the anti-copper deposition characteristic are adhered to and completely cover the first surface of the daughter board, so that direct contact between the low-flow prepreg and outer copper of the daughter board is prevented, on one hand, the outer copper of the daughter board except for a crimping hole area is not required to be etched, the manufacturing difficulty of a PCB is effectively reduced, the thickness of a finished product PCB is prevented from being increased due to the low-flow prepreg remaining in the part of the daughter board except for the crimping hole area, high and low steps formed between the crimping hole and the through hole are prevented from being formed due to the low-flow prepreg remaining in the part of the daughter board except for the crimping hole area, the surface evenness of the PCB is effectively improved, the subsequent difficulty of inserting and assembling components on the PCB is reduced, and the user experience is effectively improved; on the other hand, the copper foil covers the first surface of the daughter board through the low-flow prepreg and the isolation sheet, so that the problem that the crimping holes are damaged due to biting of liquid medicine during subsequent through hole manufacturing and/or wet process processing such as biting of liquid medicine during mother board manufacturing can be avoided, and the quality of the PCB is effectively improved.

Drawings

FIG. 1 is a flow chart of the execution of the PCB manufacturing method of the present invention;

FIG. 2 is a schematic plan view of the daughter board of the present invention after fabrication of the crimp hole area;

FIG. 3 is a schematic view of the structure of the daughter board of the present invention after the area of the crimp hole is made;

FIG. 4 is a schematic view of the structure of the invention after the spacer is adhered to and completely covers the first surface of the daughter board;

FIG. 5 is a schematic view of the structure of FIG. 4 after windowing;

FIG. 6 is a schematic plan view of the spacer of FIG. 4 after a windowing process;

FIG. 7 is a schematic plan view of a windowed low flow prepreg stacked on the structure of FIG. 6;

FIG. 8 is a schematic view of a structure in which a windowed low flow prepreg is stacked on the structure of FIG. 6;

FIG. 9 is a schematic diagram of the structure after the through holes are formed on the motherboard;

FIG. 10 is a schematic view of a structure after the copper foil on the mother board is opened;

FIG. 11 is a schematic view of the structure after the copper foil on the mother substrate is removed;

FIG. 12 is a schematic view of a structure after the spacer on the motherboard is opened;

fig. 13 is a schematic diagram of the structure after the removal of the spacers and low flow prepreg on the motherboard.

Detailed Description

In order to explain technical contents, structural features, and objects and effects of the present invention in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.

Referring to fig. 1 to 13, the PCB100 of the present embodiment is manufactured by a PCB manufacturing method, which includes the following steps:

s1, manufacturing at least one crimping hole area 20 on the sub-plate 10, wherein at least one crimping hole 30 is arranged in each crimping hole area 20.

It is understood that the drawings related to the present embodiment all illustrate one of the crimp hole regions 20 of the PCB100, and the number of the crimp hole regions 20 of the PCB100 may be one, two, three, or four. A plurality of crimp holes 30 penetrating the first surface and the second surface as shown in fig. 3 are disposed in the crimp hole region 20, and preferably, in order to facilitate the insertion and installation of the component, N × N crimp holes 30 are disposed in each crimp hole region 20 in an array to meet various insertion and installation requirements of the component, and at this time, the crimp hole region 20 is rectangular. Fig. 2 shows an arrangement of 5 x 5 crimp holes 30 in one crimp hole region 20.

The N × N crimp holes 30 arranged in an array may have the same row pitch and the same column pitch, or may have different row pitches and the same column pitches, and the crimp hole regions 20 have a square shape. Of course, the crimp holes 30 in each crimp hole region 20 may also be arranged in a non-matrix manner to meet the requirements of inserting and mounting more components.

In addition, when only one crimping hole 30 is provided in the crimping hole region 20, the region where the crimping hole 30 is located is the corresponding crimping hole region 20, and the manufacturing method thereof is consistent with the method of the PCB100 corresponding to the crimping holes 30 arranged in the non-matrix manner, which is not described herein again.

S2, adhering the spacer 40 with anti-copper deposition characteristic to completely cover the first surface of the daughter board 10.

Preferably, the spacer 40 of the embodiment is a high temperature resistant tape with copper deposition resistance, high temperature resistance and double-sided adhesion, and the spacer 40 can provide a physical bonding force with the low flow prepreg 50 and the outer copper of the sub-board 10, but does not provide a chemical bonding force with the outer copper of the sub-board 10 to form a chemical reaction, so that the low flow prepreg 50 is indirectly pressed on the sub-board 10 through the spacer 40. Since the spacer 40 only physically bonds with the copper on the exterior of the daughter board 10, the lower flow prepreg 50 of the spacer 40 is more easily removed from the first surface of the daughter board 10.

The spacer 40 of the embodiment needs to completely cover the first surface of the daughter board 10 as shown in fig. 4, so as to avoid that when the low-flow prepreg 50 is subsequently laminated, the low-flow prepreg 50 is directly contacted with the outer copper layer of the daughter board 10 due to incomplete coverage of the spacer 40 on the first surface of the daughter board 10, which results in uneven surface of the PCB 100.

S3, laser windowing the spacers 40 and the low flow prepreg 50 respectively to form a first windowing portion 41 at the circumferential side position of the spacers 40 corresponding to the crimp hole regions 20, a second windowing portion 42 at the drilling position of the spacers 40 corresponding to each crimp hole 30, and a third windowing portion 51 at the drilling position of the low flow prepreg 50 corresponding to each crimp hole 30. Fig. 5 shows a schematic view of the arrangement of fig. 4 after the windowed spacer 40 has been stacked.

It is understood that since the crimp hole region 20 of the present embodiment has a rectangular shape, the first window portion 41 has a rectangular ring shape as shown in fig. 6. In order to facilitate the control of the adhesion force between the low-flow prepreg 50 corresponding to the spacer 40 above the first window-opening part 41 and each part of the periphery of the crimp hole region 20, preferably, the first window-opening part 41 and the crimp hole region 20 are concentrically arranged, the crimp hole region 20 is located in the region surrounded by the inner edge of the first window-opening part 41, and the distance between the outer edge of the first window-opening part 41 and the corresponding edge of the crimp hole region 20 is between 9.5Mil and 10.5Mil, so as to ensure that the spacer 40 can reliably adhere to the crimp hole region 20, thereby preventing the crimp hole 30 from being bitten and damaged by the infiltration of liquid medicine.

Similarly, the second windowing portion 42 and the crimping hole 30 are concentrically arranged as shown in fig. 6, and the diameter of the second windowing portion 42 is 2.5 to 3.5Mil larger than the diameter of the crimping hole 30, so that on one hand, the crimping hole 30 is exposed outside the spacer 40, and on the other hand, the spacer 40 can be reliably adhered to the edge of the crimping hole 30.

Preferably, the diameter of the third fenestration 51 is larger than that of the second fenestration 42 as shown in fig. 7, so as to prevent the low-flow prepreg 50 from flowing into the crimp hole 30 during the subsequent pressing process.

S4, sequentially stacking the low-flow prepreg 50 and the copper foil 60 on the separator 40, and performing a pressing process after the second surfaces of the two daughter boards 10 are stacked oppositely to obtain a mother board.

In the plate pressing process, the copper foil 60 is indirectly pressed on the first surface of the daughter board 10 through the low-flow prepreg 50 and the spacer 40 as shown in fig. 8, on one hand, the copper foil 60 tightly seals the drilling positions of all the crimping holes 30 under the adhesion of the low-flow prepreg 50, and the problem that the crimping holes 30 are damaged due to the fact that liquid medicine permeates into the crimping holes 30 from the drilling positions of the crimping holes 30 in the subsequent wet process involved in the through hole 70 manufacturing process is avoided; on the other hand, the low-flow prepreg 50 is indirectly adhered to the first surface of the daughter board 10 through the spacer 40, etching of outer-layer copper of the daughter board 10 except the crimping hole region 20 is not needed, the manufacturing difficulty of the PCB100 is effectively reduced, the phenomenon that the thickness of the finished PCB100 is increased due to the low-flow prepreg 50 remaining in the part of the daughter board 10 except the crimping hole region 20 is avoided, the phenomenon that the crimping hole 30 and the through hole 70 form a high-low step due to the low-flow prepreg 50 remaining in the region of the daughter board 10 except the crimping hole region 20 is avoided, the evenness of the surface of the PCB100 is effectively improved, the subsequent plugging and assembling difficulty of components on the PCB100 is reduced, and the user experience is effectively improved.

Specifically, a prepreg 90 needs to be stacked between the second surfaces of the two daughter boards 10, so as to realize the pressing and fixing between the two daughter boards 10 after the pressing process, thereby ensuring that the manufactured mother board has a stable pressing structure.

S5, forming at least one through hole 70 for the motherboard.

S6, removing the copper foil 60 and the spacer 40 to manufacture the PCB 100.

Preferably, the step (5) specifically includes:

s51, drilling the motherboard to form at least one through hole 70 penetrating the upper and lower surfaces of the motherboard. The drilling position of the through hole 70 may be drilled in the crimp hole region 20 or outside the crimp hole region 20, preferably outside the crimp hole region 20, according to the actual production requirements. Fig. 9 shows a schematic structural diagram of the motherboard after the through hole 70 is formed, and the relationship between the through hole 70 and the crimp hole 30 can be clearly obtained from fig. 9.

And S52, performing copper deposition, electroplating treatment and surface treatment on the through hole 70.

It can be understood that, in the process of performing the copper deposition, the electroplating treatment and the surface treatment on the through hole 70, a wet process such as chemical bite is involved, and since the crimping hole 30 is closed by the copper foil 60, the chemical does not enter the crimping hole 30, thereby preventing the internal structure of the crimping hole 30 from being damaged by the chemical bite. In addition, in the actual manufacturing process, a plurality of through holes 70 are usually drilled in a specific region of the motherboard to form a through hole region, which is convenient for subsequent manufacturing and application.

Because the spacer 40 has the anti-copper deposition characteristic, when the through hole 70 is subjected to copper deposition treatment, the copper deposition layer of the through hole 70 is separated by the spacer 40, so that the bonding of the low-flow prepreg 50 and the copper deposition layer of the spacer 40 and/or the through hole 70 after copper deposition is avoided, and the subsequent tearing of the spacer 40 and the low-flow prepreg 50 is facilitated.

Preferably, in the step (6), removing the copper foil 60 and the spacer 40 specifically includes:

and S61, performing laser cutting treatment on the copper foil 60 on the outer side of the motherboard to form a notch in the copper foil 60 on the outer side of the motherboard, so that the copper foil 60 can be torn off in a whole block from the outer side of the motherboard in the subsequent steps.

S62, picking the copper foil 60 from the low flow prepreg 50 and removing the copper foil 60.

It is understood that the notch may be formed in a ring shape at the edge of the copper foil 60 on the outer side of the mother board, so as to facilitate tearing off the copper foil 60 in one piece from the outer side of the mother board. Of course, the notch may be a linear notch to slowly tear the copper foil 60 in the current crimp hole area 20 along the position of the linear notch.

In a specific operation, as shown in fig. 10, the copper foil 60 is firstly separated from the low flow prepreg 50 by using a knife such as a scalpel, so that the copper foil 60 and the separated part of the low flow prepreg 50 are in a separated state, and then the copper foil 60 is completely torn from the low flow prepreg 50 along the separated part by a manual or mechanical method, so as to complete the removal process of the copper foil 60.

S63, the spacers 40 are separated from the daughter board 10 and the spacers 40 are removed.

Since only the low-flow prepreg 50 and the spacers 40 bonded together as shown in fig. 11 remain on the first surface of the daughter board 10 after the step (62), the removal process of the low-flow prepreg 50 can be completed simultaneously by only removing the spacers 40 directly bonded to the first surface of the daughter board 10.

In a specific operation, as shown in fig. 12, the spacers 40 are first separated from the daughter board 10 by using a tool such as a ceramic grinding board and/or a knife, so that the daughter board 10 and the separated portions of the spacers 40 are separated, and then the spacers 40 are completely torn from the first surface of the daughter board 10 along the separated portions by a manual or mechanical method, so as to complete the removing process of the low-flow prepreg 50 and the spacers 40, thereby obtaining the PCB100 with a flush surface as shown in fig. 13.

Up to this point, a mother board in which the drilling position of the crimp hole 30 and the drilling position of the through hole 70 have the same height and flush surface is obtained.

The step (1) is also preceded by:

s101, manufacturing inner layer patterns of each layer of core board 80.

S102, performing brown oxidation treatment on the core plates 80 of all layers.

The purpose of this step is to react each layer of core plates 80 in the daughter board 10 with the browning liquid medicine through the browning process, and to generate a layer of dense organic browning film on the copper surface of the core plates 80, so as to enhance the bonding force between each layer of core plates 80 and the corresponding prepreg 90, and to improve the pressing stability of each layer of core plates 80. It should be noted that before lamination, prepregs 90 are stacked between adjacent core plates 80, and the prepregs 90 are respectively bonded to the adjacent core plates 80 under pressure, so as to achieve lamination fixation between the adjacent core plates 80.

And S103, stacking the core plates 80 according to a preset stacking sequence, and then performing plate pressing treatment to obtain the sub-plate 10.

Specifically, prepregs 90 need to be stacked between adjacent core plates 80 to achieve the press-fit fixation between the adjacent core plates 80 after the pressing process.

Preferably, the step (1) specifically comprises:

s11, drilling in each preset crimping hole area 20 of the sub-board 10 to form at least one crimping hole 30;

s12, performing copper deposition, electroplating and surface treatment on the crimping hole 30.

It is understood that, as described in the foregoing steps, the fabrication process of the crimp hole 30 is earlier than that of the through hole 70, and the fabrication of the crimp hole 30 involves copper deposition, plating, and surface treatment, and thus, a certain structure is formed in the crimp hole 30. As can be seen from the steps (51) and (52), the manufacturing process of the through hole 70 also involves copper deposition, electroplating and surface treatment, so that the drilling position of the crimp hole 30 is closed by the copper foil 60 to prevent the chemical solution from penetrating into the crimp hole 30 and effectively ensure the insertion performance and the electrical performance of the crimp hole 30 in order to avoid the damage of the wet process such as chemical solution biting involved in the manufacturing of the through hole 70 to the structure of the already manufactured crimp hole 30.

Preferably, in the step (6), the removing the copper foil 60 and the spacer 40 further includes:

s7, manufacturing an outer layer graph of the motherboard;

And (5) obtaining a finished PCB100 through the step (1) and the step (8).

With reference to fig. 1 to 13, in the present invention, the spacer 40 with copper deposition resistance is adhered to and completely covers the first surface of the daughter board 10 to block the low-flow prepreg 50 from directly contacting the outer copper layer of the daughter board 10, so that on one hand, etching of the outer copper layer of the daughter board 10 except for the crimping hole area 20 is not required, the manufacturing difficulty of the PCB100 is effectively reduced, and the increase of the thickness of the finished PCB100 due to the low-flow prepreg 50 remaining in the portion of the daughter board 10 except for the crimping hole area 20 is avoided, so as to avoid the formation of a high-low step between the crimping hole 30 and the through hole 70 due to the low-flow prepreg 50 remaining in the area of the daughter board 10 except for the crimping hole area 20, effectively improve the leveling property of the PCB surface, reduce the subsequent difficulty of inserting and assembling components on the PCB, and effectively improve the user experience; on the other hand, the copper foil 60 covers the first surface of the daughter board 10 through the low-flow prepreg 50 and the spacer 40, so that the damage of the crimping holes 30 due to the biting of the liquid medicine during the subsequent through hole 70 manufacturing and/or wet process treatment such as the biting of the liquid medicine to the mother board can be avoided, and the quality of the PCB100 can be effectively improved.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, therefore, the present invention is not limited by the appended claims.

Claims

1. A manufacturing method of a PCB is characterized by comprising the following steps:

manufacturing at least one crimping hole area for the daughter board, wherein each crimping hole area is internally provided with at least one crimping hole;

adhering a spacer with copper deposition resistance to completely cover the first surface of the daughter board;

respectively carrying out laser windowing on the spacers and the low-flow prepregs to form first windowing parts at the positions of the spacers corresponding to the peripheral sides of the crimping hole areas, form second windowing parts at the positions of the spacers corresponding to the drilling holes of each crimping hole, and form third windowing parts at the positions of the low-flow prepregs corresponding to the drilling holes of each crimping hole, wherein the first windowing parts and the crimping hole areas are concentrically arranged, the crimping hole areas are positioned in the area surrounded by the inner edges of the first windowing parts, the second windowing parts and the crimping holes are concentrically arranged, the diameters of the second windowing parts are larger than the diameters of the crimping holes, and the diameters of the third windowing parts are larger than the diameters of the second windowing parts;

sequentially stacking the low-flow prepreg and the copper foil on the isolating sheet, oppositely stacking the second surfaces of the two daughter boards, and then pressing the two daughter boards to obtain a mother board;

manufacturing at least one through hole on the motherboard;

and removing the copper foil and the spacing sheet to obtain the PCB.

2. The method for fabricating a PCB according to claim 1, wherein the fabricating at least one via hole to the motherboard specifically comprises:

drilling the motherboard to form at least one through hole;

and carrying out copper deposition, electroplating treatment and surface treatment on the through hole.

3. The method for manufacturing a PCB of claim 1, wherein the removing the copper foil and the spacer specifically comprises:

carrying out laser cutting treatment on the copper foil to form a notch on the copper foil;

picking the copper foil from the spacer and removing the copper foil;

and the isolation sheet is separated from the daughter board and removed.

4. The method of claim 3, wherein the copper foil is teased away from the sub-board and removed by a cutter, and the spacer is teased away from the sub-board and removed by a ceramic grind board and/or a cutter.

5. The method of claim 1, wherein the spacer is a high temperature resistant tape, ink layer or dry film layer with copper deposition resistance.

6. The method of claim 1, wherein the daughter board is formed with at least one crimp hole area, each crimp hole area having at least one crimp hole therein, and further comprising:

making inner layer patterns of each core plate;

performing brown oxidation treatment on each layer of core plate;

and after the core plates of all layers are stacked according to a preset stacking sequence, carrying out plate pressing treatment to obtain the sub-plate.

7. The method of claim 1, wherein a plurality of crimp holes are formed in the crimp hole region, all of the crimp holes in each of the crimp hole regions are arranged in an array to form a rectangular crimp hole region, the first fenestration is in a shape of a rectangular ring, an outer edge of the first fenestration is spaced from a corresponding edge of the crimp hole region by a distance of 9.5 to 10.5 mils, and a diameter of the second fenestration is 2.5 to 3.5 mils larger than the diameter of the crimp holes.

8. The method for manufacturing a PCB according to claim 1, wherein the manufacturing of the daughter board includes at least one crimping hole area, and at least one crimping hole is provided in each crimping hole area, and the method specifically includes:

drilling in each preset crimping hole area of the daughter board respectively to form at least one crimping hole;

and carrying out copper deposition, electroplating treatment and surface treatment on the crimping hole.

9. The method of claim 1, wherein removing the copper foil and the spacers further comprises:

manufacturing an outer layer graph of the motherboard;

and carrying out green oil treatment, surface treatment and appearance milling treatment on the mother board.