CN113225940A

CN113225940A - PCB manufacturing method and PCB

Info

Publication number: CN113225940A
Application number: CN202110486308.1A
Authority: CN
Inventors: 刘潭武; 纪成光; 王洪府; 杜红兵; 王小平; 陈长平; 肖璐
Original assignee: Shengyi Electronics Co Ltd
Current assignee: Shengyi Electronics Co Ltd
Priority date: 2021-04-30
Filing date: 2021-04-30
Publication date: 2021-08-06
Anticipated expiration: 2041-04-30
Also published as: CN113225940B

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 the isolation sheet and completely covering the corresponding crimping hole area of the first surface of the daughter board; respectively carrying out laser ablation treatment on the isolation sheet and the low-flow prepreg; after the low-flow prepreg is superposed on the spacer, pre-lamination treatment is carried out; removing the spacers and the low-flow prepregs which are pressed on the daughter board except the pressing hole area; carrying out pressing plate treatment to obtain a mother plate; manufacturing at least one through hole on the motherboard; removing the copper foil and the low-flow prepreg 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

PCB manufacturing method and PCB

Technical Field

The invention relates to the technical field of Printed Circuit Boards (PCBs), in particular to a PCB manufacturing method and 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 avoid 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 reduce the difficulty of subsequently inserting and installing components on the PCB and effectively improve 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 the isolation sheet and completely covering the corresponding crimping hole area of the first surface of the daughter board;

s3, performing laser ablation treatment on the isolation sheet and the low-flow prepreg respectively to form a first windowing part at the position of the isolation sheet corresponding to the crimping hole area and a second windowing part at the drilling position of the low-flow prepreg corresponding to each crimping hole;

s4, after the low flow prepreg is stacked on the spacer, performing a pre-pressing process to directly press the portion of the low flow prepreg corresponding to the first fenestration on the area of the crimping holes, and exposing each crimping hole to the external environment through the corresponding second fenestration;

s5, removing the spacers and the low-flow prepregs which are pressed on the daughter board except the crimping hole area;

s6, overlapping copper foils on the low-flow prepregs, oppositely overlapping the second surfaces of the two daughter boards, and pressing the two daughter boards to obtain a mother board;

s7, manufacturing at least one through hole on the motherboard;

and S8, removing the copper foil and the low-flow prepreg to obtain the PCB.

Preferably, the step (4) specifically includes:

s41, overlapping the low-flow prepreg on the isolating sheet;

and S42, pre-pressing the daughter board at a pressing temperature of 165-175℃ until the part of the low-flow prepreg corresponding to the first windowing part passes through the first windowing part and is directly contacted and pressed on the first surface of the daughter board, and each second windowing part is opposite to the corresponding crimping hole, so that each crimping hole is exposed to the external environment through the corresponding second windowing part.

Preferably, the step (5) specifically includes:

and S51, performing laser ablation treatment on the spacers and the low-flow prepregs on the daughter board except the first windowing part so as to enable the spacers and the low-flow prepregs on the daughter board except the first windowing part to be separated from the daughter board.

Preferably, after the step (6) and before the step (7), the method further comprises:

s601, removing the copper foil except the crimping hole area by adopting an ultraviolet laser ablation process so as to only retain the copper foil pressed above the crimping hole area.

Preferably, the step (8) specifically includes:

s81, carrying out laser cutting processing on the copper foil to form a notch at the copper foil above the crimping hole area;

s82, removing the copper foil and the low-flow prepreg above the crimping hole area;

and S83, grinding the copper foil and the low-flow prepreg remained in the crimping hole area by adopting a ceramic grinding plate.

Preferably, the vertical projection of all the second windowing part constituting regions in the same crimping hole region is located in the vertical projection of the first windowing part, and the vertical projection of the crimping hole region is located in the vertical projection of all the second windowing part constituting regions in the crimping hole region.

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;

s12, carrying out copper deposition, electroplating and surface treatment on the crimping hole;

the step (7) specifically comprises:

s71, drilling the motherboard to form at least one through hole;

and S72, carrying out copper deposition, electroplating treatment and surface treatment on the through hole.

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 rectangular, the first windowing part and the crimping hole area are concentrically arranged, the area of the first windowing part is larger than that of the crimping hole area, the crimping hole area is located in an area surrounded by an inner edge of the first windowing part, and the distance between the edge of the first windowing part and the corresponding edge of the crimping hole area is 9.5-10.5 Mil;

the second portion of windowing with the crimping hole is concentric setting, just the diameter of second portion of windowing is greater than the diameter of crimping hole 4.5Mil to 5.5 Mil.

Preferably, step (1) is preceded by:

s1001, manufacturing inner layer patterns of each core board;

s1002, performing brown oxidation treatment on each layer of core board;

s1003, after the core boards of all layers are stacked according to a preset stacking sequence, performing plate pressing treatment to obtain the daughter boards;

the step (8) is followed by:

s9, manufacturing an outer layer graph of the motherboard;

and S10, 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 invention completely covers the corresponding crimping hole area of the first surface of the daughter board by sticking the isolation sheet, the first windowing part is arranged at the position of the isolation sheet corresponding to the crimping hole area, the second windowing part is arranged at the drilling position of the low-flow prepreg corresponding to each crimping hole, after the low-flow prepreg is superposed on the isolation sheet, the pre-pressing treatment is carried out, so that the part of the low-flow prepreg corresponding to the first windowing part is directly crimped on the crimping hole area, each crimping hole is exposed to the external environment through the corresponding second windowing part, the direct contact between the low-flow prepreg and the first surface of the daughter board except the crimping hole area is blocked by the isolation sheet, and the low-flow prepreg is only directly contacted with the part of the first surface of the daughter board corresponding to the crimping hole area, on one hand, the outer layer copper of the daughter board except the crimping hole area is not required to be etched, the manufacturing difficulty of the PCB is effectively reduced, the problem that the thickness of the finished product PCB is increased due to the fact that low-flow prepregs are left in the part of the daughter board except the crimping hole area is avoided, therefore, the problem that high and low steps are formed between the crimping hole and the through hole due to the fact that the low-flow prepregs are left in the part of the daughter board except the crimping hole area is avoided, the surface evenness of the PCB is effectively improved, the difficulty of subsequently inserting and installing components on the PCB is reduced, and user experience is effectively improved; on the other hand, the copper foil covers the first surface at the daughter board through low flowing prepreg, can avoid the crimping hole follow-up preparation through-hole and/or because of the liquid medicine bites when carrying out wet flow process such as liquid medicine bites and grazes and damages when the mother board, effectively promotes PCB's quality.

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 structural view of the spacer of the present invention after it is adhered to and completely covers the corresponding crimping hole area of the first surface of the daughter board;

FIG. 5 is a schematic view of the spacer after the windowing process of the present invention;

FIG. 6 is a schematic view of a structure in which a windowed low flow prepreg is stacked on the structure of FIG. 5;

FIG. 7 is a schematic plan view of a windowed low flow prepreg stacked on the structure of FIG. 5;

FIG. 8 is a schematic view of the structure of FIG. 6 after pre-bonding;

FIG. 9 is a schematic view of the structure of FIG. 8 after removing the spacers and low flow prepreg that are press bonded to the daughter board except for the press bond hole area;

FIG. 10 is a schematic view of the structure of FIG. 9 after copper foil has been laminated thereon;

FIG. 11 is a schematic view of the two FIG. 10 structures after being subjected to a platen process;

FIG. 12 is a schematic view of the structure of FIG. 11 with the copper foil removed except in the crimp hole area;

FIG. 13 is a schematic structural diagram of the mother board after through holes are formed;

fig. 14 is a schematic view of the structure after removing the low flow prepreg and the copper foil on the mother board.

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 14, the PCB100 of the present embodiment is manufactured by a partial press-fit manufacturing method of the PCB100, wherein the partial press-fit manufacturing method of the PCB100 includes the following steps:

s1, manufacturing at least one crimping hole area 20 for the sub-plate 10, wherein each crimping hole area 20 is provided with at least one crimping hole 30.

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 distributed in an array may have the same row spacing and column spacing, or may have different row spacing and column spacing, and when the row spacing and the column spacing are the same, 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.

And S2, adhering the spacing piece 40 to completely cover the corresponding crimping hole area 20 of the first surface of the daughter board 10.

Preferably, the separator 40 of the embodiment is a high temperature resistant tape with high temperature resistance and double-sided adhesiveness, the separator 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 due to a chemical reaction, and the low-flow prepreg 50 can be subsequently pressed on the sub-board 10 through the window of the separator 40. Since the spacers 40 are only physically bonded to the copper of the outer layer of the daughter board 10, the lower flow prepreg 50 of the spacers 40 is more easily removed from the first surface of the daughter board 10. In other embodiments, the spacer 40 may also be an ink or a dry film.

The spacer 40 of the present embodiment needs to completely cover the entire crimp hole area 20 as shown in fig. 4, and ensure that the coverage area of the spacer 40 is larger than the area formed by all the low flow prepregs 50 in the current crimp hole area 20, so that the subsequent low flow prepregs 50 can be subsequently pressed in the current crimp hole area 20 through the windowed portion of the spacer 40, and ensure that the low flow prepregs 50 flow out of the crimp hole area 20 of the daughter board 10.

S3, laser ablation processing is performed on the spacers 40 and the low flow prepreg 50 to form a first fenestration 41 at a position of the spacer 40 corresponding to the crimp hole area 20 and a second fenestration 51 at a drilling position of the low flow prepreg 50 corresponding to each crimp hole 30, respectively. Fig. 5 shows a schematic view of the structure of fig. 3 after the windowed spacer 40 is 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 shape at this time. Preferably, the first windowing portion 41 and the crimping hole area 20 are concentrically arranged, and the crimping hole area 20 is located in an area surrounded by the inner edge of the first windowing portion 41, and the distance between the outer edge of the first windowing portion 41 and the corresponding edge of the crimping hole area 20 is between 9.5Mil and 10.5Mil, so that the low-flow prepreg 50 covers and seals the outer edge of the crimping hole area 20, and the liquid medicine is effectively prevented from permeating into the crimping hole 30 to damage the crimping hole 30.

Similarly, the second fenestration 51 and the crimp hole 30 are arranged concentrically as shown in fig. 7, and the diameter of the second fenestration 51 is 2.5 to 3.5Mil larger than the diameter of the crimp hole 30, on one hand, the crimp hole 30 is ensured to be exposed outside the low-flow prepreg 50, and on the other hand, the low-flow prepreg 50 is ensured to be reliably adhered to the edge position of the crimp hole 30, and the low-flow prepreg 50 is prevented from flowing into the crimp hole 30 in the subsequent pressing process.

Preferably, the vertical projection of all the second windowing parts 51 constituting regions in the same crimp hole region 20 is located within the vertical projection of the first windowing part 41, and the vertical projection of the crimp hole region 20 is located within the vertical projection of all the second windowing parts 51 constituting regions in the crimp hole region 20. At this time, as shown in fig. 6, the low flow prepreg 50 above the edge of the crimp hole region 20 protrudes outside the edge of the crimp hole region 20, so that in the pre-pressing in the subsequent step (4), the inner portion of the edge of the crimp hole region 20, where the low flow prepreg 50 above the edge of the crimp hole region 20 protrudes, will be pressed at the inner position of the edge of the crimp hole region 20 corresponding to the first surface of the daughter board 10, and it is ensured that the low flow prepreg 50 above the edge of the crimp hole region 20 can be located outside the edge of the crimp hole region 20 after being pressed, so that the subsequent copper foil 60 can be effectively pressed and completely cover and close the entire crimp hole region 20.

S4, after the low flow prepreg 50 is stacked on the separator 40, a pre-pressing process is performed to directly press the portion of the low flow prepreg 50 corresponding to the first fenestration 41 onto the crimp hole region 20, and each of the crimp holes 30 is exposed to the external environment through the corresponding second fenestration 51.

Fig. 8 shows the relative positional relationship of the daughter board 10, the spacer 40, and the low flow prepreg 50 after the pre-press bonding process, in which the portion of the low flow prepreg 50 corresponding to the first window 41 passes through the first window 41 under pressure and is vertically press-bonded to the press bonding hole area 20 of the daughter board 10.

S5, removing the spacers 40 and the low flow prepreg 50 pressed on the sub board 10 except the crimp hole regions 20. Fig. 9 is a schematic view illustrating the structure of the sub-board 10 after removing the spacers 40 and the low flow prepreg 50 laminated on the sub-board 10 except the crimp hole region 20, in which the low flow prepreg 50 is laminated only in the crimp hole region 20 on the first surface of the sub-board 10.

S6, stacking the copper foil 60 on the low flow prepreg 50, stacking the second surfaces of the two daughter boards 10 opposite to each other, and then performing a pressing process 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 as shown in fig. 10, 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, so that the problem that the pressing 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, since the low-flow prepreg 50 is only laminated in the crimping hole area 20 on the first surface of the daughter board 10, the area of the physical bonding force and the chemical bonding force generated between the low-flow prepreg 50 and the first surface of the daughter board 10 is small, and the low-flow prepreg 50 and the first surface of the daughter board 10 are relatively easy to remove in the subsequent steps, the copper foil 60 has good local positioning and sealing effects on the crimping hole area 20 through the laminating mode of the low-flow prepreg 50, and the problem that the low-flow prepreg 50 cannot be completely removed due to the fact that the whole low-flow prepreg 50 is directly adhered to the first surface of the daughter board 10 is avoided.

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.

S7, forming at least one through hole 70 for the motherboard.

S8, removing the copper foil 60 and the low flow prepreg 50 to obtain the PCB 100.

Preferably, the step (4) specifically includes:

s41, stacking the low flow prepreg 50 on the separator 40;

s42, pre-pressing the sub-board 10 at a pressing temperature between 165 ℃ and 175℃ until the portion of the low-flow prepreg 50 corresponding to the first windowed portion 41 passes through the first windowed portion 41 and is vertically and directly contacted and pressed on the first surface of the sub-board 10, and each of the second windowed portions faces the corresponding press-connection hole 30, so that each of the press-connection holes 30 is exposed to the external environment through the corresponding second windowed portion 51. According to the test, the structure is subjected to pre-pressing treatment at the pressing temperature of 165-175 degrees centigrade, so that the low-flow prepreg 50 is not completely solidified, the low-flow prepreg 50 and the copper surface of the first surface of the daughter board 10 corresponding to the crimping hole area 20 can be stably pressed, and the separator 40 is not melted on the first surface of the daughter board 10.

Preferably, the step (5) specifically includes:

s51, performing laser ablation on the spacers 40 and the low-flow prepreg 50 on the daughter board 10 except for the first fenestration 41. Specifically, a laser ablation process is performed in the AA' direction as shown in fig. 8 to detach the spacers 40 and the low-flow prepreg 50 on the sub-board 10 except for the first windowed portions 41 from the sub-board 10 to obtain the structure shown in fig. 9.

s601, removing the copper foil 60 except the crimping hole area 20 by adopting an ultraviolet laser ablation process so as to only retain the copper foil 60 pressed above the crimping hole area 20. This step is intended to remove the copper foil 60 outside the crimp hole region 20 and prevent the infiltration of a chemical along the bottom of the copper foil 60 outside the crimp hole region 20.

Preferably, the step (8) specifically includes:

s81, performing a laser cutting process on the copper foil 60 above the crimp hole region 20 to form a notch at the copper foil 60 above the crimp hole region 20.

S82, removing the copper foil 60 and the low-flow prepreg 50 above the crimping hole area 20. The copper foil 60 may be torn by hand or by machine, and the low-flow prepreg 50 may be opened by a knife such as a scalpel.

And S83, grinding the copper foil 60 and the low-flow prepreg 50 remained above the crimping hole area 20 by using a ceramic grinding plate.

Because only the copper foil 60 and the low-flow prepreg 50 are left in the crimping holes 30 after the step (82), and only a small amount of copper foil 60 and low-flow prepreg 50 are left in the motherboard, in order to avoid the residual copper foil 60 and low-flow prepreg 50 from affecting the surface flatness of the PCB100, the step performs secondary treatment on the residues on the surface of the PCB100 by adopting a grinding mode to ensure the obtained PCB100 with a flat surface, and the grinding mode causes relatively small abrasion to the PCB 100.

Preferably, the step (1) specifically includes:

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

and S12, performing copper deposition, electroplating treatment and surface treatment on the crimping hole 30.

The step (7) specifically comprises:

s71, 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 can be drilled in the crimping hole area 20 or outside the crimping hole area 20 according to the actual production requirement, fig. 13 shows a schematic structural diagram of the motherboard after the through hole 70 is manufactured, and the relationship between the through hole 70 and the crimping hole 30 can be clearly obtained through fig. 13.

And S72, carrying out copper deposition, electroplating treatment and surface treatment on the through hole 70.

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 step (71) and the step (72), the manufacturing process of the through hole 70 also involves copper deposition, electroplating and surface treatment, so that the drilling position of the crimping hole 30 is closed by the copper foil 60 to prevent the chemical solution from infiltrating into the crimping hole 30 and effectively ensure the insertion performance and the electrical performance of the crimping hole 30 in order to avoid the damage of wet processes such as chemical solution bite and the like to the structure of the manufactured crimping hole 30 when the through hole 70 is manufactured.

Preferably, step (1) is preceded by:

and S1001, manufacturing an inner layer pattern of each layer of core board 80.

S1002, 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.

S1003, stacking the core plates 80 of all layers according to a preset stacking sequence, and then performing plate pressing treatment to obtain the daughter board 10;

the step (8) is followed by:

s9, manufacturing an outer layer graph of the motherboard;

Through the step (1) and the step (10), the finished PCB100 can be obtained.

Referring to fig. 1 to 14, the present invention provides a method for manufacturing a semiconductor device, which includes adhering a spacer 40 to completely cover a crimp hole region 20 corresponding to a first surface of a sub-board 10, providing a first louver 41 at a position of the spacer 40 corresponding to the crimp hole region 20, providing a second louver 51 at a position of a low flow prepreg 50 corresponding to a drilling position of each crimp hole 30, laminating the low flow prepreg 50 on the spacer 40, performing a pre-press process such that a portion of the low flow prepreg 50 corresponding to the first louver 41 is directly pressed on the crimp hole region 20 and each of the crimp holes 30 is exposed to an external environment through the corresponding second louver 51, blocking direct contact of the low flow prepreg 50 with a portion of the first surface of the sub-board 10 other than the crimp hole region 20 by the spacer 40, and directly contacting the low flow prepreg 50 with only a portion of the first surface of the sub-board 10 corresponding to the crimp hole region 20, on one hand, because the low-flow prepreg 50 is only in direct contact with the part, corresponding to the crimping hole area 20, of the first surface of the daughter board 10, the contact area between the low-flow prepreg 50 and the daughter board 10 is small, and the physical bonding force and the chemical bonding force of the low-flow prepreg 50 are greatly reduced compared with the physical bonding force and the chemical bonding force of the conventional low-flow prepreg 50, which are completely in contact with the daughter board 10, so that the subsequent removal of the low-flow prepreg 50 is facilitated, and the formation of steps on the surfaces of the crimping hole 30 and the through hole 70 of the PCB100 due to the existence of the low-flow prepreg 50 is effectively avoided, thereby reducing the subsequent difficulty in inserting and mounting components on the PCB100 and effectively improving 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, so that the crimping holes 30 can be prevented from being damaged by liquid medicine biting during subsequent through hole 70 manufacturing and/or wet process processing such as liquid medicine biting performed on the mother board, 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 the isolation sheet to completely cover the corresponding crimping hole area of the first surface of the daughter board;

respectively carrying out laser ablation treatment on the isolation sheet and the low-flow prepreg to form a first windowing part at the position of the isolation sheet corresponding to the crimping hole area and a second windowing part at the drilling position of the low-flow prepreg corresponding to each crimping hole;

after the low-flow prepreg is superposed on the isolating sheet, pre-pressing treatment is carried out, so that the part, corresponding to the first windowing part, of the low-flow prepreg is directly pressed on the crimping hole area, and each crimping hole is exposed to the external environment through the corresponding second windowing part;

removing the spacers and the low-flow prepregs which are pressed on the daughter board except the first windowing part;

stacking copper foils on the low-flow prepregs, stacking the second surfaces of the two daughter boards oppositely, 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 low-flow prepreg to obtain the PCB.

2. The method according to claim 1, wherein after the low flow prepreg is stacked on the spacer, a pre-pressing process is performed to directly press a portion of the low flow prepreg corresponding to the first fenestration onto the area of the crimp holes, and each of the crimp holes is exposed to an external environment through a corresponding second fenestration, and specifically comprises:

stacking the low flow prepreg on the separator;

and pre-pressing the daughter board at a pressing temperature of 165-175℃ until the part of the low-flow prepreg corresponding to the first windowing part passes through the first windowing part and is directly contacted and pressed on the first surface of the daughter board, and each second windowing part is opposite to the corresponding crimping hole, so that each crimping hole is exposed to the external environment through the corresponding second windowing part.

3. The method of claim 1, wherein the removing the spacers and the low flow prepreg bonded to the daughter board except for the first windowed portions comprises:

and carrying out laser ablation treatment on the spacers and the low-flow prepregs on the daughter board except the first windowing part so as to enable the spacers and the low-flow prepregs on the daughter board except the first windowing part to be separated from the daughter board.

4. The method for manufacturing a PCB of claim 1, wherein after the steps of stacking a copper foil on the low flow prepreg and stacking the second surfaces of the two daughter boards opposite to each other, pressing the two daughter boards to form a mother board, and before the step of forming at least one through hole in the mother board, the method further comprises:

and removing the copper foil except the crimping hole area by adopting an ultraviolet laser ablation process.

5. The method of claim 1, wherein the removing the copper foil and the low flow prepreg to produce the PCB comprises:

carrying out laser cutting treatment on the copper foil to form a notch at the copper foil above the crimping hole area;

removing the copper foil and the low-flow prepreg above the crimping hole area;

and grinding the copper foil and the low-flow prepreg remained above the crimping hole area by adopting a ceramic grinding plate.

6. The method of claim 1, wherein a vertical projection of all second fenestration areas within the same crimp aperture area is within a vertical projection of the first fenestration, and wherein a vertical projection of the crimp aperture area is within a vertical projection of all second fenestration areas within the crimp aperture area.

7. 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;

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

the manufacturing of at least one through hole for the motherboard specifically includes:

drilling the motherboard to form at least one through hole;

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

8. The method of claim 1, wherein a plurality of crimp holes are formed in the crimp hole region, all the crimp holes in each of the crimp hole regions are distributed in an array to form a rectangular crimp hole region, the first fenestration is rectangular, the first fenestration is concentric with the crimp hole region, the area of the first fenestration is larger than that of the crimp hole region, the crimp hole region is located in a region surrounded by an inner edge of the first fenestration, and the distance between the edge of the first fenestration and the corresponding edge of the crimp hole region is 9.5 to 10.5 mils;

9. 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;

after the core plates of all layers are stacked according to a preset stacking sequence, carrying out plate pressing treatment to obtain the daughter boards;

the copper foil and the spacing sheet are removed in sequence, and then the method further comprises the following steps:

manufacturing an outer layer graph of the motherboard;

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

10. A PCB manufactured according to the method of manufacturing a PCB according to any of claims 1-9.