CN113692141A - Printed circuit hole interconnection structure and manufacturing method thereof - Google Patents
Printed circuit hole interconnection structure and manufacturing method thereof Download PDFInfo
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- CN113692141A CN113692141A CN202110984113.XA CN202110984113A CN113692141A CN 113692141 A CN113692141 A CN 113692141A CN 202110984113 A CN202110984113 A CN 202110984113A CN 113692141 A CN113692141 A CN 113692141A
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- printed circuit
- board
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- 238000004519 manufacturing process Methods 0.000 title claims abstract description 19
- 238000005553 drilling Methods 0.000 claims abstract description 31
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 18
- 229910052802 copper Inorganic materials 0.000 claims abstract description 18
- 239000010949 copper Substances 0.000 claims abstract description 18
- 238000000034 method Methods 0.000 claims abstract description 10
- 238000007731 hot pressing Methods 0.000 claims abstract description 4
- 238000001465 metallisation Methods 0.000 claims description 11
- 238000010030 laminating Methods 0.000 claims description 2
- 238000003475 lamination Methods 0.000 claims description 2
- 230000015572 biosynthetic process Effects 0.000 claims 1
- 238000003825 pressing Methods 0.000 abstract description 5
- 230000008054 signal transmission Effects 0.000 abstract description 5
- 238000010586 diagram Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 150000003071 polychlorinated biphenyls Chemical class 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
- H05K3/42—Plated through-holes or plated via connections
- H05K3/429—Plated through-holes specially for multilayer circuits, e.g. having connections to inner circuit layers
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/11—Printed elements for providing electric connections to or between printed circuits
- H05K1/115—Via connections; Lands around holes or via connections
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/0011—Working of insulating substrates or insulating layers
- H05K3/0044—Mechanical working of the substrate, e.g. drilling or punching
- H05K3/0047—Drilling of holes
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/46—Manufacturing multilayer circuits
- H05K3/4611—Manufacturing multilayer circuits by laminating two or more circuit boards
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/02—Details related to mechanical or acoustic processing, e.g. drilling, punching, cutting, using ultrasound
- H05K2203/0214—Back-up or entry material, e.g. for mechanical drilling
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/06—Lamination
Abstract
The invention provides a printed circuit hole interconnection structure and a manufacturing method thereof. And only the holes of the first sub-plate hole and the second sub-plate hole in the stepped hole are provided with the metalized copper layers. The manufacturing method comprises the following steps: manufacturing a first sub-board and a second sub-board, and respectively drilling through holes at preset positions; then pressing the mother board in a hot pressing mode to form a mother board; drilling through holes in the through holes of the first sub-board and the second sub-board for the first time to obtain a stepped hole; and after the hole is metalized, drilling a through hole in the stepped hole for the second time to obtain the hole interconnection structure. The invention uses the drill to break the small hole of the inner layer which does not need the signal to pass through, and the method can reduce the signal loss and improve the signal transmission quality.
Description
Technical Field
The invention belongs to the technical field of printed circuit boards, and particularly relates to a printed circuit hole interconnection structure and a manufacturing method thereof.
Background
The advancement of 5 th generation mobile communication technology has enabled circuit signal transmission frequencies to be greatly increased. The 5G network is fast in speed and safer and more efficient, and the rapid development of the advanced technologies such as the Internet of things, big data, unmanned driving and cloud storage is greatly promoted. However, the development of 5G brings convenience to technology, and simultaneously, higher requirements are put on the performance of each device of electronic products. The transmission frequency of 5G signals usually reaches above 28GHz, and for a circuit board as a parent of an electronic product, signal integrity problems such as increased signal transmission loss, distortion and the like are attracted to wide attention in the field of PCBs as the signal transmission frequency increases.
In printed circuit designs, vias are bridges that connect the lines of each layer, however in practice not all layers need to be interconnected, and if conventional vias are not processed, the signal is transmitted over the extra copper pillars, commonly referred to as stubs. At high frequency signals, stubs can have a large effect on the signal. The presence of stubs can cause impedance discontinuities and thus create reflections, resonances. In the literature, "HFSS-based high-speed PCB signal integrity research", the simulation analysis of S parameters and impedances of different stub lengths shows that the longer the stub, the smaller the impedance of the via hole, and the resonant frequency moves to a low frequency, which obviously has a great influence on the signal. Currently, the PCB manufacturing industry mainly solves the problem of signal integrity caused by stub via back drilling. The back drilling refers to a process of performing secondary drilling after the through hole is finished and removing redundant residual piles. Conventional mechanical drilling has relatively poor control accuracy of the depth of the drill point, so that the back drill which needs to accurately control the depth of the drill point must use a special drilling machine. In the back drilling process, when the drill point contacts the copper on the surface of the circuit board, weak current can be generated, and the feedback is used as a starting point of the drilling depth so as to accurately control the accuracy of the back drilling.
However, backdrilling is not applicable for the case where a single via needs to break the internal several layers of interconnects.
Disclosure of Invention
In view of the above, the invention provides a printed circuit hole interconnection structure and a manufacturing method thereof, aiming at the situation that the conventional process in the existing printed circuit board can not break the inner layer hole copper, the invention forms a large-small hole structure by drilling a hole on a sub-board after lamination, and then carries out whole board hole metallization, and then uses a drill with the diameter between the large hole and the small hole to drill off the hole copper of the small hole, thereby being capable of breaking the unnecessary hole copper of the inner layer, and improving the transmission quality of signals in the through hole.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a method for manufacturing a printed circuit hole interconnection structure comprises the following steps:
(1) a first daughter board 101 with the number of layers m is manufactured and has a diameter DaThe drill bit drills a through hole at a preset position to form a first sub-plate hole 103;
(2) making the number n of layersTwo sub-boards 102, and the combined diameter is DaThe drilling tool drills a through hole to form a second sub-plate hole 104, and the central axes of the first sub-plate hole 103 and the second sub-plate hole 104 are aligned;
(3) laminating the first daughter board 101, the prepreg 106, the core board 105, the prepreg 106 and the second daughter board 102 in sequence from top to bottom in a hot pressing mode to form a mother board, wherein the number of the core board layers is s;
(4) drilling the mother board prepared in the step (3), namely drilling the hole with the diameter D under the condition that the drilling tool is aligned with the central axes of the first daughter board hole and the second daughter board holebThe drill bit drills a through hole for the first time in the first sub-plate hole 103 and the second sub-plate hole 104 to obtain a stepped hole 108;
(5) performing hole metallization on the motherboard containing the stepped hole 108 prepared in the step (4), so that a copper layer is formed on the wall of the stepped hole, and a metallized stepped hole 109 is formed;
(6) with the drill bit aligned with the central axis of the stepped bore, with a diameter DcThe drill performs a second drilling of the via hole in the stepped hole, and a printed circuit hole interconnection structure 110 is obtained, wherein only the holes of the first sub-plate hole 103 and the second sub-plate hole 104 have the copper metallization layers.
Preferably, the drill used in the steps (1), (2), (4) and (6) has a diameter size relationship of: da>Dc>Db。
Preferably, the number of layers of the daughter boards is more than or equal to 2, n is more than or equal to 2, the number of layers of the core board is more than or equal to 2, and m, n and s are positive integers.
Preferably, before the pressing in step (3), alignment holes are formed in the plate edges, so that central axes of the first sub-plate hole 103 and the second sub-plate hole 104 are aligned.
The invention also provides a printed circuit hole interconnection structure which comprises a stepped hole, wherein the stepped hole is formed by connecting a first subplate hole 103, a prepreg hole, a chip hole, a prepreg hole and a second subplate hole 104 which are aligned with the central axis from top to bottom in sequence, and the aperture of the first subplate hole 103 and the aperture of the second subplate hole 104 are larger than the aperture of the prepreg hole and the aperture of the chip hole.
Preferably, the stepped hole has a copper metallization layer only in the holes of the first sub-plate hole 103 and the second sub-plate hole 104, and no copper metallization layer in the other holes of the stepped hole.
Preferably, the inner diameters of the first sub-plate hole 103 and the second sub-plate hole 104 are 0.1 to 0.6 mm.
Preferably, the diameters of the core holes and the prepreg holes are smaller than the diameters of the first sub-plate holes 103 and the second sub-plate holes 104 by 0.02mm to 0.2 mm.
The principle and the beneficial effects of the invention are as follows:
the invention has made a ladder-shaped hole interconnection structure and its preparation method, drill the hole in order to disconnect the inner layer does not need the small hole that the signal passes through with the drilling tool, can reduce the signal loss effectively through this method, improve the signal transmission quality; compared with an HDI manufacturing process, the manufacturing method reduces the pressing times in the manufacturing process of the printed circuit board with more layers. Meanwhile, compared with HDI blind and buried hole manufacturing, the mother board only needs PTH once, and manufacturing procedures are simplified. In addition, the drilling operation of all the processes is through hole drilling, depth control drilling is not needed, and the process difficulty is reduced to a certain extent.
Drawings
FIG. 1 is a schematic diagram of a 4-layer sub-board structure in step 1 of the present invention;
FIG. 2 is a schematic diagram of the structure of the daughter board after drilling in step 2 of the present invention;
FIG. 3 is a schematic view of step 3 press-fit stack-up of the present invention;
FIG. 4 is a schematic diagram of a mother board obtained after the pressing in step 3 according to the present invention;
FIG. 5 is a schematic diagram of the mother board obtained after the first through hole drilling in step 4 of the present invention;
FIG. 6 is a schematic view of the mother board after step 5 hole metallization of the present invention;
fig. 7 is a schematic diagram of the mother board obtained after the second through hole drilling in step 6 of the present invention.
101 is a first daughter board, 102 is a second daughter board, 103 is a first daughter board hole, 104 is a second daughter board hole, 105 is a core board, 106 is a prepreg, 107 is a mother board, 108 is a stepped hole, 109 is a metallized stepped hole, and 110 is a printed circuit hole interconnection structure.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention.
Example 1
A method for manufacturing a printed circuit hole interconnection structure comprises the following steps:
(1) as shown in FIG. 1, a first sub-board 101 having a layer number m of 4 is fabricated and used with a diameter DaDrilling a through hole at a preset position by using a drill bit with the diameter of 0.4mm to form a first sub-plate hole 103, as shown in fig. 2;
(2) as shown in FIG. 1, a second sub-board 102 having a number n of layers of 4 is fabricated and used with a diameter DaDrilling a through hole for a drill with the diameter of 0.4mm to form a second sub-plate hole 104, wherein as shown in fig. 2, central axes of the first sub-plate hole 103 and the second sub-plate hole 104 are aligned;
(3) as shown in fig. 3, after being stacked in the order of the first daughter board 101, the prepreg 106, the core board 105, the prepreg 106, and the second daughter board 102 from top to bottom, the mother board is formed by pressing in a hot pressing manner, as shown in fig. 4, where the number s of core board layers is 2; before the pressfitting, the plate edge is provided with the counterpoint hole, so that the central axes of the two holes of the first subplate hole and the second subplate hole are aligned.
(4) As shown in fig. 5, the mother board obtained in step (3) is drilled, i.e. with the diameter D aligned with the central axes of the first and second sub-board holesbDrilling a through hole for the first time in the first subplate hole and the second subplate hole of the first subplate and the second subplate hole by using a drill bit of 0.2 to obtain a stepped hole 108;
(5) performing hole metallization on the motherboard containing the stepped hole 108 prepared in the step (4), so that a copper layer is formed on the wall of the stepped hole, and a metallized stepped hole 109 is formed; as shown in fig. 6;
(6) in the drill and the stepDiameter D with the central axes of the holes alignedcAnd drilling a through hole for the second time in the stepped hole by using a drill with the diameter of 0.3mm to obtain the printed circuit hole interconnection structure 110, wherein only the holes of the first sub-plate hole 103 and the second sub-plate hole 104 are provided with the metalized copper layers. As shown in fig. 7;
the diameter size relation of the drill used in the steps (1), (2), (4) and (6) is as follows: da>Dc>Db。
The number of layers m of the daughter boards is more than or equal to 2, n is more than or equal to 2, the number of layers s of the core board is more than or equal to 2, and m, n and s are positive integers.
This embodiment still provides a printed circuit hole interconnect structure, contains the shoulder hole, and the shoulder hole is connected from last to being formed by first subplate hole 103, prepreg hole, chip hole, prepreg hole, the second subplate hole 104 that the axis aligns down in proper order, and wherein the aperture in first subplate hole 103 and second subplate hole 104 is greater than the aperture in prepreg hole and chip hole.
The stepped hole has only the first sub-plate hole 103 and the second sub-plate hole 104 with copper metallization layers in the holes, and has no copper metallization layer in other holes of the stepped hole.
The inner diameters of the first subplate hole 103 and the second subplate hole 104 are 0.1-0.6 mm.
The aperture of the core plate hole and the aperture of the prepreg hole are smaller than the aperture of the first subplate hole 103 and the aperture of the second subplate hole 104 by 0.02 mm-0.2 mm.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (8)
1. A method for manufacturing a printed circuit hole interconnection structure is characterized by comprising the following steps:
(1) a first sub-plate (101) with the number of layers m is manufactured and used with a diameter DaThe drill bit drills a through hole at a preset position to form a first sub-plate hole (103);
(2) a second daughter board (102) is produced with a number of layers n, with a diameter DaThe drilling tool drills a through hole to form a second sub-plate hole (104), and the central axes of the first sub-plate hole (103) and the second sub-plate hole (104) are aligned;
(3) laminating the first daughter board (101), the prepreg (106), the core board (105), the prepreg (106) and the second daughter board (102) from top to bottom in sequence in a hot pressing mode to form a mother board, wherein the number of the core board layers is s;
(4) drilling the mother board prepared in the step (3), namely drilling the hole with the diameter D under the condition that the drilling tool is aligned with the central axes of the first daughter board hole and the second daughter board holebThe drill bit drills a through hole for the first time in a first sub-plate hole (103) and a second sub-plate hole (104) to obtain a stepped hole (108);
(5) performing hole metallization on the motherboard containing the stepped hole (108) prepared in the step (4), so that a copper layer is formed on the wall of the stepped hole, and a metallized stepped hole (109) is formed;
(6) with the drill bit aligned with the central axis of the stepped bore, with a diameter DcAnd (3) drilling a through hole for the second time in the stepped hole by using the drill to obtain the printed circuit hole interconnection structure (110), wherein only the holes of the first sub-plate hole (103) and the second sub-plate hole (104) are internally provided with the copper metallization layers.
2. A method of making a printed circuit via interconnect structure as claimed in claim 1, wherein: the diameter size relation of the drill used in the steps (1), (2), (4) and (6) is as follows: da>Dc>Db。
3. A method of making a printed circuit via interconnect structure as claimed in claim 1, wherein: the number of layers m of the daughter boards is more than or equal to 2, n is more than or equal to 2, the number of layers s of the core board is more than or equal to 2, and m, n and s are positive integers.
4. A method of making a printed circuit via interconnect structure as claimed in claim 1, wherein: and (4) before lamination in the step (3), aligning holes are formed in the plate edges, so that the central axes of the first sub-plate hole (103) and the second sub-plate hole (104) are aligned.
5. A printed circuit via interconnect structure, comprising: contain the shoulder hole, the shoulder hole is from last to connecting the formation by first subplate hole (103), prepreg hole, core plate hole, prepreg hole, second subplate hole (104) that the axis aligns down in proper order, and wherein the aperture in first subplate hole (103) and second subplate hole (104) is greater than the aperture in prepreg hole and core plate hole.
6. A printed circuit hole interconnect structure as claimed in claim 5, wherein: the stepped hole only has a metalized copper layer in the holes of the first sub-plate hole (103) and the second sub-plate hole (104), and the other holes of the stepped hole do not have metalized copper layers.
7. A printed circuit hole interconnect structure as claimed in claim 5, wherein: the inner diameters of the first sub-plate hole (103) and the second sub-plate hole (104) are 0.1-0.6 mm.
8. A printed circuit hole interconnect structure as claimed in claim 5, wherein: the aperture of the core plate hole and the aperture of the prepreg hole are 0.02 mm-0.2 mm smaller than the aperture of the first subplate hole (103) and the aperture of the second subplate hole (104).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110984113.XA CN113692141A (en) | 2021-08-25 | 2021-08-25 | Printed circuit hole interconnection structure and manufacturing method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110984113.XA CN113692141A (en) | 2021-08-25 | 2021-08-25 | Printed circuit hole interconnection structure and manufacturing method thereof |
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| Publication Number | Publication Date |
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| CN113692141A true CN113692141A (en) | 2021-11-23 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202110984113.XA Pending CN113692141A (en) | 2021-08-25 | 2021-08-25 | Printed circuit hole interconnection structure and manufacturing method thereof |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103687306A (en) * | 2012-09-05 | 2014-03-26 | 北大方正集团有限公司 | Printed circuit board and manufacturing method thereof |
| CN105916294A (en) * | 2016-05-20 | 2016-08-31 | 广州杰赛科技股份有限公司 | Printed circuit board back hole drilling manufacturing method and printed circuit board thereof |
| CN107592756A (en) * | 2017-09-27 | 2018-01-16 | 生益电子股份有限公司 | The preparation method of high-density multi-layered PCB a kind of and high-density multi-layered PCB |
-
2021
- 2021-08-25 CN CN202110984113.XA patent/CN113692141A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103687306A (en) * | 2012-09-05 | 2014-03-26 | 北大方正集团有限公司 | Printed circuit board and manufacturing method thereof |
| CN105916294A (en) * | 2016-05-20 | 2016-08-31 | 广州杰赛科技股份有限公司 | Printed circuit board back hole drilling manufacturing method and printed circuit board thereof |
| CN107592756A (en) * | 2017-09-27 | 2018-01-16 | 生益电子股份有限公司 | The preparation method of high-density multi-layered PCB a kind of and high-density multi-layered PCB |
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Application publication date: 20211123 |