CN116634662B - High-speed printed circuit board and preparation method thereof - Google Patents
High-speed printed circuit board and preparation method thereof Download PDFInfo
- Publication number
- CN116634662B CN116634662B CN202310904379.8A CN202310904379A CN116634662B CN 116634662 B CN116634662 B CN 116634662B CN 202310904379 A CN202310904379 A CN 202310904379A CN 116634662 B CN116634662 B CN 116634662B
- Authority
- CN
- China
- Prior art keywords
- copper
- clad plate
- signal layer
- clad
- plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000002360 preparation method Methods 0.000 title abstract description 7
- 238000005553 drilling Methods 0.000 claims abstract description 54
- 239000000758 substrate Substances 0.000 claims abstract description 30
- 238000000034 method Methods 0.000 claims description 38
- 238000004519 manufacturing process Methods 0.000 claims description 20
- 230000000149 penetrating effect Effects 0.000 claims description 18
- 238000003475 lamination Methods 0.000 claims description 16
- 238000010030 laminating Methods 0.000 claims description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 12
- 229910052802 copper Inorganic materials 0.000 description 9
- 239000010949 copper Substances 0.000 description 9
- 238000010586 diagram Methods 0.000 description 7
- 238000003825 pressing Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 5
- 229920005989 resin Polymers 0.000 description 4
- 239000011347 resin Substances 0.000 description 4
- 239000011889 copper foil Substances 0.000 description 3
- 102100035964 Gastrokine-2 Human genes 0.000 description 2
- 101001075215 Homo sapiens Gastrokine-2 Proteins 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000003822 epoxy resin Substances 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 150000003071 polychlorinated biphenyls Chemical class 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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
- 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
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/0296—Conductive pattern lay-out details not covered by sub groups H05K1/02 - H05K1/0295
- H05K1/0298—Multilayer circuits
-
- 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
- H05K3/0017—Etching of the substrate by chemical or physical means
- H05K3/0026—Etching of the substrate by chemical or physical means by laser ablation
-
- 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
-
- 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
- H05K3/40—Forming printed elements for providing electric connections to or between printed circuits
- H05K3/42—Plated through-holes or plated via connections
- H05K3/421—Blind plated 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
- H05K3/40—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
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/46—Manufacturing multilayer circuits
- H05K3/4602—Manufacturing multilayer circuits characterized by a special circuit board as base or central core whereon additional circuit layers are built or additional circuit boards are laminated
-
- 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
Abstract
The invention discloses a high-speed printed circuit board and a preparation method thereof, wherein the high-speed printed circuit board comprises: the copper-clad plates comprise conductive layers, insulating substrates and signal layers which are sequentially stacked; the core plate comprises a supporting substrate and two conductive layers respectively positioned on two opposite side surfaces of the supporting substrate; the core board is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates are symmetrically arranged on the first side and the second side of the core board; the prepregs are positioned between the copper-clad plate and the core plate and between the adjacent copper-clad plates; the blind holes are positioned on the first side, and penetrate through the copper-clad plate positioned on the first side and farthest from the core plate to the signal layer on the first side; the through holes comprise back drilling holes, and penetrate through the high-speed printed circuit board; the back drilling hole is positioned on the second side of the core plate, and penetrates through the signal layer on the second side from the copper-clad plate positioned on the second side and farthest from the core plate. The invention can reduce the cost and improve the signal integrity.
Description
Technical Field
The invention relates to the technical field of printed circuit boards, in particular to a high-speed printed circuit board and a preparation method thereof.
Background
With the continuous improvement of the performance of the display card, the frequency of signals on the modern high-performance display card is also higher and higher, and signals with the frequency of up to tens of GHZ are all the same. Since the number of signal lines is very large, the speed requirement is also fast, and many signal layers are required to complete the wiring requirement. In addition, as the chip size becomes smaller and smaller, the pin pitch becomes smaller, and blind holes have become the option to meet routing requirements, which results in very high manufacturing costs for PCBs.
Fig. 1 is a schematic structural diagram of a printed circuit board in the prior art, referring to fig. 1, for a conventional high-speed blind hole circuit board, a laser drilling process is mainly adopted in a preparation mode of a blind hole 30, because of limitation of a laser hole, the drilling thickness is limited, and each layer is required to be pressed once after being manufactured, and then the blind hole is punched again for pressing again, so that the cost is high. Fig. 2 is a schematic structural diagram of another printed circuit board in the prior art, referring to fig. 2, the printed circuit board is pressed once, and the design of the through hole 40 is that the conventional through hole board has a larger minimum aperture size because of the limitation of the precision of the through hole 40 and the limitation of the aperture ratio of the copper plating of the through hole, and cannot meet the requirement of a small aperture (especially under a chip), and in addition, because of the process limitation of the back drilling 41, residual copper (stub) exists in the through hole, which can greatly affect the signal integrity.
Disclosure of Invention
The invention provides a high-speed printed circuit board and a preparation method thereof, which are used for reducing the cost and improving the signal integrity.
According to an aspect of the present invention, there is provided a high-speed printed circuit board comprising:
the copper-clad plates comprise conductive layers, insulating substrates and signal layers which are sequentially stacked;
the core plate comprises a supporting substrate and two conductive layers respectively positioned on two opposite side surfaces of the supporting substrate; the core board is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates are symmetrically arranged on the first side and the second side of the core board;
the prepregs are positioned between the copper-clad plate and the core plate and between the adjacent copper-clad plates;
the blind holes are positioned on the first side, and penetrate through the copper-clad plate positioned on the first side and farthest from the core plate to the signal layer on the first side;
the through holes comprise back drilling holes, and penetrate through the high-speed printed circuit board; the back drilling hole is positioned on the second side of the core plate, and penetrates through the signal layer on the second side from the copper-clad plate positioned on the second side and farthest from the core plate.
Optionally, the signal layer includes: a high-speed signal layer and a second high-speed signal layer;
the high-speed signal layer is positioned in the copper-clad plate at the first side of the core plate;
the secondary high-speed signal layer is positioned in the copper-clad plate at the second side of the core plate.
Optionally, the high-speed printed circuit board includes:
the first copper-clad plate, the first prepreg, the second copper-clad plate, the second prepreg, the core plate, the third prepreg, the third copper-clad plate, the fourth prepreg and the fourth copper-clad plate are sequentially stacked; the first copper-clad plate and the fourth copper-clad plate are symmetrically arranged, the second copper-clad plate and the third copper-clad plate are symmetrically arranged, the first copper-clad plate comprises a first signal layer, the second copper-clad plate comprises a second signal layer, the third copper-clad plate comprises a third signal layer, the fourth copper-clad plate comprises a fourth signal layer, the first signal layer and the second signal layer are high-speed signal layers, and the third signal layer and the fourth signal layer are secondary high-speed signal layers;
the first blind hole is positioned at the first side, penetrates through the first copper-clad plate and penetrates through the first signal layer;
the second blind hole is positioned at the first side, penetrates through the first copper-clad plate, the first prepreg and the second copper-clad plate and penetrates through the second signal layer;
a first through hole including a first back-drilled hole penetrating the high-speed printed circuit board; the first back drilling hole is positioned at the second side, penetrates through the fourth copper-clad plate and penetrates through the fourth signal layer;
the second through hole comprises a second back drilling hole, and penetrates through the high-speed printed circuit board; the second back drilling hole is located at the second side, penetrates through the fourth copper-clad plate, the fourth prepreg and the third copper-clad plate and penetrates through the third signal layer.
Optionally, the aperture of the blind hole is 0.1mm, and the aperture of the through hole is more than or equal to 0.2mm.
According to another aspect of the present invention, there is provided a method of manufacturing a high-speed printed circuit board, comprising:
forming a plurality of copper-clad plates, wherein each copper-clad plate comprises a conductive layer, an insulating substrate and a signal layer which are sequentially laminated;
forming a core plate, wherein the core plate comprises a supporting substrate and two conductive layers respectively positioned on two opposite side surfaces of the substrate;
forming prepregs between two adjacent copper-clad plates on the first side of the core plate for lamination, and forming a plurality of blind holes on the first side of the core plate; the blind hole penetrates through the signal layer of the first side from the copper-clad plate positioned at the first side and farthest from the core plate;
forming prepregs between two adjacent copper-clad plates on the second side of the core plate and between the core plate and the copper-clad plates on the two sides for lamination, and forming a plurality of through holes penetrating through the high-speed printed circuit board; the core board is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates are symmetrically arranged on the first side and the second side of the core board;
forming a back-drilled hole in the through-hole; the back drilling hole is positioned on the second side of the core plate, and penetrates through the signal layer on the second side from the copper-clad plate positioned on the second side and farthest from the core plate.
Optionally, the signal layer includes a high-speed signal layer and a second-high-speed signal layer, and forming the signal layer includes:
forming a high-speed signal layer in the copper-clad plate at the first side of the core plate;
and forming a secondary high-speed signal layer in the copper-clad plate at the second side of the core plate.
Optionally, the high-speed printed circuit board comprises a first copper-clad plate, a first prepreg, a second copper-clad plate, a second prepreg, a core plate, a third prepreg, a third copper-clad plate, a fourth prepreg and a fourth copper-clad plate which are sequentially stacked; forming the prepreg between two adjacent copper-clad plates on the first side of the core plate for lamination, and forming a plurality of blind holes on the first side of the core plate, comprising:
forming a first blind hole in the first copper-clad plate; the first blind hole penetrates through the first copper-clad plate and penetrates through the first signal layer; the first copper-clad plate comprises a first signal layer;
forming a first prepreg on the first copper-clad plate;
laminating the first copper-clad plate and the second copper-clad plate through the first prepreg; the second copper-clad plate comprises a second signal layer, and the first signal layer and the second signal layer are high-speed signal layers;
forming a second blind hole in the second copper-clad plate; the second blind hole penetrates through the first copper-clad plate, the first prepreg and the second copper-clad plate and penetrates through the second signal layer.
Optionally, a prepreg is formed between two adjacent copper-clad plates on the second side of the core board and between the core board and the copper-clad plates on both sides for lamination, and a plurality of through holes penetrating the high-speed printed circuit board are formed, including:
disposing a second prepreg on the first side surface of the core board, and forming a third prepreg on the second side surface;
a third copper-clad plate is arranged on a third prepreg; the third copper-clad plate comprises a third signal layer;
forming a fourth prepreg on the third copper-clad plate;
the fourth copper-clad plate is arranged on the fourth prepreg, the third copper-clad plate and the fourth copper-clad plate are pressed on the second side of the core plate through the third prepreg and the fourth prepreg, and the pressed first copper-clad plate and second copper-clad plate are pressed on the first side of the core plate through the second prepreg; the first copper-clad plate and the fourth copper-clad plate are symmetrically arranged, the second copper-clad plate and the third copper-clad plate are symmetrically arranged, the fourth copper-clad plate comprises a fourth signal layer, and the third signal layer and the fourth signal layer are secondary high-speed signal layers;
first and second through holes are formed through the high speed printed circuit board.
Optionally, forming a back-drilled hole in the through-hole includes:
forming a first back borehole in the first via; the first back drilling hole is positioned at the second side, penetrates through the fourth copper-clad plate and penetrates through the fourth signal layer;
forming a second back borehole in the second via; the second back drilling hole is located at the second side, penetrates through the fourth copper-clad plate, the fourth prepreg and the third copper-clad plate and penetrates through the third signal layer.
Optionally, forming the plurality of blind holes includes:
forming a plurality of blind holes through a laser hole process or a mechanical hole process;
forming a plurality of through holes through the high speed printed circuit board includes:
a plurality of through holes penetrating the high-speed printed circuit board are formed through a mechanical hole process.
The high-speed printed circuit board provided by the technical scheme of the invention comprises: the copper-clad plates comprise conductive layers, insulating substrates and signal layers which are sequentially stacked; the core plate comprises a supporting substrate and two conductive layers respectively positioned on two opposite side surfaces of the supporting substrate; the core board is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates are symmetrically arranged on the first side and the second side of the core board; the prepregs are positioned between the copper-clad plate and the core plate and between the adjacent copper-clad plates; the blind holes are positioned on the first side, and penetrate through the copper-clad plate positioned on the first side and farthest from the core plate to the signal layer on the first side; the through holes comprise back drilling holes, and penetrate through the high-speed printed circuit board; the back drilling hole is positioned on the second side of the core plate, and penetrates through the signal layer on the second side from the copper-clad plate positioned on the second side and farthest from the core plate. The invention can achieve the best balance of cost and performance by adopting a mode of combining the blind holes and the through holes. Compared with the design of adopting full through holes in the prior art, all signal layers need to adopt back drilling forms, and as back drilling remains, the signal integrity of the back drilling forms is inferior to that of a blind hole, and the requirement cannot be met in the occasion with extremely high requirement on the signal integrity of an ultra-high-speed signal line. In addition, the aperture of the through hole is large, and the method cannot be applied to places with extremely limited wiring space, or if the method adopts a full blind hole design, the production process is complex, the price is very high, and the cost is very high. The invention adopts the mode of combining the blind hole, the through hole and the back drilling hole, thereby not only reducing the cost, but also maximally ensuring the signal integrity because of adopting the blind hole design.
It should be understood that the description in this section is not intended to identify key or critical features of the invention or to delineate the scope of the invention. Other features of the present invention will become apparent from the description that follows.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a printed circuit board in the prior art;
FIG. 2 is a schematic diagram of a printed circuit board according to another prior art;
fig. 3 is a schematic structural diagram of a high-speed printed circuit board according to a first embodiment of the present invention;
FIG. 4 is a schematic view of a high-speed printed circuit board according to a first embodiment of the present invention;
fig. 5 is a flowchart of a method for manufacturing a high-speed printed circuit board according to a second embodiment of the present invention;
FIG. 6 is a refinement flow chart included in step 300;
fig. 7 is a refinement flowchart included in step 400.
Description of the embodiments
In order that those skilled in the art will better understand the present invention, a technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
It should be noted that the terms "first," "second," and the like in the description and the claims of the present invention and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the invention described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Examples
An embodiment of the present invention provides a high-speed printed circuit board, and fig. 3 is a schematic structural diagram of the high-speed printed circuit board provided in the first embodiment of the present invention, and referring to fig. 3, the high-speed printed circuit board includes: the copper-clad laminate (10) comprises a conductive layer (11), an insulating substrate (12) and a signal layer (13) which are sequentially laminated; a core board 20, the core board 20 including a support substrate 21 and two conductive layers 11 respectively located on opposite side surfaces of the support substrate 21; the core board 20 is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates 10 are symmetrically arranged on the first side and the second side of the core board 20; a plurality of prepregs 50, the prepregs 50 being located between the copper-clad plate 10 and the core plate 20, and between the adjacent copper-clad plates 10; the blind holes 30 are positioned on the first side, and the blind holes 30 penetrate through the copper-clad plate 10 positioned on the first side and farthest from the core plate 20 to the signal layer 13 on the first side; a plurality of through holes 40, the through holes 40 including back holes 41, the through holes 40 penetrating the high-speed printed circuit board; the back drilling 41 is located on the second side of the core 20 and extends through the copper-clad laminate 10 located on the second side furthest from the core 20 to the signal layer 13 on the second side.
The high-speed printed circuit board shown in fig. 3 includes four copper-clad plates 10, four prepregs 50, two blind holes 30, two through holes 40 and two back drilling holes 41. The material of the conductive layer 11 in the copper-clad plate 10 can be copper foil, and the material of the insulating substrate 12 can be epoxy resin; the supporting base plate 21 in the core plate 20 is a hard plate material with a specific thickness; the prepreg mainly comprises resin and glass fiber cloth. The plurality of copper clad laminates 10, the core laminate 20 and the plurality of prepregs 50 are integrally bonded by a lamination process, and under the condition of high temperature and high pressure, the resin in the prepregs 50 can melt and flow to bond the layers together. The blind hole 30 can be prepared by a laser hole process or a mechanical hole process; the method of fabricating the via 40 may employ a mechanical hole process to electroplate copper into the blind via 30 and the via 40. A back-drilling 41 may be formed on the back of the via 40 by a back-drilling process to drill out via segments that do not function as a connection or transmission. The metal copper not connected in the smaller diameter via 40 may be drilled away with a larger diameter drill bit to reduce signal loss.
The high-speed printed circuit board provided by the technical scheme of the embodiment of the invention comprises: the copper-clad laminate (10) comprises a conductive layer (11), an insulating substrate (12) and a signal layer (13) which are sequentially laminated; a core board 20, the core board 20 including a support substrate 21 and two conductive layers 11 respectively located on opposite side surfaces of the support substrate 21; the core board 20 is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates 10 are symmetrically arranged on the first side and the second side of the core board 20; a plurality of prepregs 50, the prepregs 50 being located between the copper-clad plate 10 and the core plate 20, and between the adjacent copper-clad plates 10; the blind holes 30 are positioned on the first side, and the blind holes 30 penetrate through the copper-clad plate 10 positioned on the first side and farthest from the core plate 20 to the signal layer 13 on the first side; a plurality of through holes 40, the through holes 40 including back holes 41, the through holes 40 penetrating the high-speed printed circuit board; the back drilling 41 is located on the second side of the core 20 and extends through the copper-clad laminate 10 located on the second side furthest from the core 20 to the signal layer 13 on the second side. The present invention achieves an optimal balance of cost and performance by employing a combination of blind holes 30 and through holes 40. Compared with the prior art that the through hole 40 is adopted, all the signal layers 13 need to be in the form of back drilling holes 41, and the back drilling holes 41 have residues, so that the signal integrity is inferior to that of the blind holes 30, and the requirements of ultra-high-speed signal wires on the occasions with extremely high signal integrity cannot be met. In addition, the through hole 40 has a large aperture, and cannot be applied to places with extremely limited wiring space, or if the through hole is designed by adopting a full blind hole, the production process is complex, the price is very high, and the cost is very high. The combination of the blind holes 30, the through holes 40 and the back drilling holes 41 can reduce the cost, and the design of the blind holes 30 can ensure the signal integrity to the greatest extent.
Optionally, the signal layer includes: a high-speed signal layer and a second high-speed signal layer; the high-speed signal layer is positioned in the copper-clad plate at the first side of the core plate; the secondary high-speed signal layer is positioned in the copper-clad plate at the second side of the core plate.
Wherein, the signal in the high-speed signal layer may be a data line portion in the GDDR memory signal, and the signal in the next-to-high-speed signal layer may be a CA line portion in the GDDR memory signal. The high-speed signal layer is arranged in the copper-clad plate at the first side of the core plate, signals are transmitted through the blind holes, the occupied space in the plate is smaller due to the smaller aperture of the blind holes, and the rest space can be used for shielding treatment, so that the optimal electrical performance of the signal layer is ensured, and the signal integrity can be ensured to the greatest extent; the secondary high-speed signal layer is arranged in the copper-clad plate at the second side of the core plate, and the production cost can be reduced by adopting a through hole and back drilling mode. The signal layer can also comprise a common signal layer, the common signal layer is positioned in the copper-clad plate at the second side of the core plate, and the common signal is directly transmitted by adopting the through hole, so that the production cost is reduced.
Optionally, fig. 4 is a schematic structural diagram of yet another high-speed printed circuit board according to the first embodiment of the present invention, and referring to fig. 4, the high-speed printed circuit board includes: the first copper-clad plate 110, the first prepreg 510, the second copper-clad plate 120, the second prepreg 520, the core plate 20, the third prepreg 530, the third copper-clad plate 130, the fourth prepreg 540 and the fourth copper-clad plate 140 are sequentially stacked; the first copper-clad plate 110 and the fourth copper-clad plate 140 are symmetrically arranged, the second copper-clad plate 120 and the third copper-clad plate 130 are symmetrically arranged, the first copper-clad plate 110 comprises a first signal layer 131, the second copper-clad plate 120 comprises a second signal layer 132, the third copper-clad plate 130 comprises a third signal layer 133, the fourth copper-clad plate 140 comprises a fourth signal layer 134, the first signal layer 131 and the second signal layer 132 are high-speed signal layers, and the third signal layer 133 and the fourth signal layer 134 are sub-high-speed signal layers.
The first blind hole 31, the first blind hole 31 is located at the first side, and the first blind hole 31 penetrates through the first copper-clad plate 110 and penetrates through to the first signal layer 131; the second blind hole 32 is positioned on the first side, and the second blind hole 32 penetrates through the first copper-clad plate 110, the first prepreg 510 and the second copper-clad plate 120 and penetrates through the second signal layer 132; a first through hole 410, the first through hole 410 including a first back drilling 411, the first through hole 410 penetrating the high speed printed circuit board; the first back drilling 411 is located at the second side, and the first back drilling 411 penetrates through the fourth copper-clad plate 140 and penetrates through the fourth signal layer 134; a second through hole 420, the second through hole 420 including a second back drilling 421, the second through hole 420 penetrating the high-speed printed circuit board; the second back drilling 421 is located at the second side, and the second back drilling 421 penetrates through the fourth copper-clad plate 140, the fourth prepreg 540, and the third copper-clad plate 130, and penetrates through to the third signal layer 133.
Wherein fig. 4 is a laminate design of 10 layers, 4 signal layers. The core board 20 is positioned in the middle of the whole high-speed printed circuit board, the high-speed signal wires are arranged on the first side of the core board 20 to form a high-speed signal layer, the first signal layer 131 and the second signal layer 132 are both high-speed signal layers, the first signal layer 131 and the second signal layer 132 transmit signals in the form of blind holes 30, and the integrity of the high-speed signals can be ensured to the greatest extent; the secondary high-speed signal lines are arranged on the second side of the core board 20 to form a secondary high-speed signal layer, the third signal layer 133 and the fourth signal layer 134 are all secondary high-speed signal layers, and the third signal layer 133 and the fourth signal layer 134 adopt a mode of combining through holes with back drilling holes, so that the production cost is reduced.
Optionally, the aperture of the blind hole is 0.1mm, and the aperture of the through hole is more than or equal to 0.2mm.
If the aperture of the blind hole is smaller than 0.1mm, the process production difficulty is high; if the aperture of the blind hole is larger than 0.1mm, the space in the high-speed printed circuit board is wasted easily; therefore, the aperture of the blind hole is 0.1mm, the process is simpler, and the utilization rate of the space in the high-speed printed circuit board can be improved. If the aperture of the through hole is smaller than 0.2mm, the process production difficulty is high, so that the aperture of the through hole is more than or equal to 0.2mm, and the process is simple and easy to operate.
Examples
The embodiment of the present invention provides a method for manufacturing a high-speed printed circuit board based on the above embodiment, and fig. 5 is a flowchart of a method for manufacturing a high-speed printed circuit board according to a second embodiment of the present invention, and referring to fig. 5, the method includes:
and 100, forming a plurality of copper-clad plates, wherein the copper-clad plates comprise conducting layers, insulating substrates and signal layers which are sequentially laminated.
Wherein, one surface of the insulating substrate is coated with copper foil to form a conductive layer.
Step 200, forming a core board, wherein the core board comprises a supporting substrate and two conductive layers respectively positioned on two opposite side surfaces of the substrate.
Copper foil is coated on two opposite sides of the supporting substrate to form two conductive layers.
Step 300, forming a prepreg between two adjacent copper-clad plates on the first side of the core plate for lamination, and forming a plurality of blind holes on the first side of the core plate; the blind hole penetrates through the signal layer of the first side from the copper-clad plate which is positioned at the first side and is farthest from the core plate.
Under the conditions of high temperature and high pressure, the resin in the prepreg can flow in a melting way, and two adjacent copper-clad plates can be bonded together in a pressing mode. In step 300, the copper clad laminate on the first side of the core board is pressed at least once. Before and/or after each lamination, forming through holes in the current all copper-clad plates by laser drilling or mechanical drilling, and after all the preset number of copper-clad plates positioned on the first side of the core plate are laminated on the core plate, the through holes in the process are used as blind holes.
Step 400, forming prepregs between two adjacent copper-clad plates on the second side of the core plate and between the core plate and the copper-clad plates on the two sides for lamination, and forming a plurality of through holes penetrating through the high-speed printed circuit board; the core board is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates are symmetrically arranged on the first side and the second side of the core board.
The prepreg is formed between two adjacent copper-clad plates on the second side of the core plate and between the core plate and the copper-clad plates on the two sides, resin in the prepreg can flow in a melting way under the condition of high temperature and high pressure, and the two adjacent copper-clad plates, the core plate and the copper-clad plates are bonded together through integral lamination; and forming a plurality of through holes by mechanical punching.
Step 500, forming a back drilling hole in the through hole; the back drilling hole is positioned on the second side of the core plate, and penetrates through the signal layer on the second side from the copper-clad plate positioned on the second side and farthest from the core plate.
Wherein, the metal copper which is not connected in the through hole with smaller diameter is drilled by the drill bit with larger diameter, thereby forming back drilling holes, and the loss of signals can be reduced by the back drilling holes.
Optionally, the signal layer includes a high-speed signal layer and a second-high-speed signal layer, and forming the signal layer includes: forming a high-speed signal layer in the copper-clad plate at the first side of the core plate; and forming a secondary high-speed signal layer in the copper-clad plate at the second side of the core plate.
The high-speed signal wire is arranged in the copper-clad plate at the first side of the core plate to form a high-speed signal layer, and the high-speed signal is transmitted through the blind hole, so that the signal integrity is greatly ensured; and the secondary high-speed signal wire is arranged in the copper-clad plate at the second side of the core plate to form a secondary high-speed signal layer, and secondary high-speed signals are transmitted through the through holes and the back drilling holes, so that the production cost is reduced.
Optionally, the high-speed printed circuit board comprises a first copper-clad plate, a first prepreg, a second copper-clad plate, a second prepreg, a core plate, a third prepreg, a third copper-clad plate, a fourth prepreg and a fourth copper-clad plate which are sequentially stacked; fig. 6 is a detailed flowchart of step 300, referring to fig. 6, step 300, forming a prepreg between two adjacent copper-clad plates on a first side of a core board for lamination, and forming a plurality of blind holes on the first side of the core board, including:
step 301, forming a first blind hole in a first copper-clad plate; the first blind hole penetrates through the first copper-clad plate and penetrates through the first signal layer; the first copper-clad plate comprises a first signal layer.
Wherein the first blind hole may be formed by a laser hole process or a mechanical hole process.
And 302, forming a first prepreg on the first copper-clad plate.
Step 303, laminating the first copper-clad plate and the second copper-clad plate through the first prepreg; the second copper-clad plate comprises a second signal layer, and the first signal layer and the second signal layer are high-speed signal layers.
And the first copper-clad plate and the second copper-clad plate are pressed for the first time through the first prepreg.
Step 304, forming a second blind hole in the second copper-clad plate; the second blind hole penetrates through the first copper-clad plate, the first prepreg and the second copper-clad plate and penetrates through the second signal layer.
Wherein the second blind hole may be formed by a laser hole process or a mechanical hole process.
Optionally, fig. 7 is a detailed flowchart included in step 400, referring to fig. 7, in step 400, prepregs are formed between two adjacent copper-clad plates on the second side of the core board and between the core board and the copper-clad plates on both sides for lamination, and a plurality of through holes penetrating the high-speed printed circuit board are formed, including:
step 401, disposing a second prepreg on the first side surface of the core board, and forming a third prepreg on the second side surface.
Step 402, arranging a third copper-clad plate on a third prepreg; the third copper-clad plate comprises a third signal layer.
And 403, forming a fourth prepreg on the third copper-clad plate.
Step 404, arranging a fourth copper-clad plate on a fourth prepreg, pressing the third copper-clad plate and the fourth copper-clad plate on the second side of the core plate through the third prepreg and the fourth prepreg, and pressing the pressed first copper-clad plate and second copper-clad plate on the first side of the core plate through the second prepreg; the first copper-clad plate and the fourth copper-clad plate are symmetrically arranged, the second copper-clad plate and the third copper-clad plate are symmetrically arranged, the fourth copper-clad plate comprises a fourth signal layer, and the third signal layer and the fourth signal layer are secondary high-speed signal layers.
If the high-speed printed circuit board is 10 layers, 4 signal layers, the high-speed printed circuit board in this embodiment may be formed by two pressing steps, the number of the signal layers on the first side of the core board determines the pressing times, one signal layer is pressed once, two signal layers are pressed twice, and so on. In the prior art, the design of the full blind hole is adopted, four times of pressing are needed, the production process is complex, the yield is low, the price is very high, and the cost is very high. Or the form of one-time lamination full through hole is adopted, all signal layers are required to be in a back drilling form, and as the back drilling is residual, the signal integrity is inferior to that of a blind hole, the requirement can not be met in the occasion that the ultra-high-speed signal wire has extremely high requirement on the signal integrity, in addition, the through hole has large aperture, and the method is inapplicable in places with extremely limited wiring space such as BGA.
Step 405, forming a first via and a second via through the high speed printed circuit board.
Wherein, the first through hole and the second through hole penetrating the high-speed printed circuit board are formed through a mechanical hole process.
Optionally, forming a back-drilled hole in the through-hole includes: forming a first back borehole in the first via; the first back drilling hole is positioned at the second side, penetrates through the fourth copper-clad plate and penetrates through the fourth signal layer; forming a second back borehole in the second via; the second back drilling hole is located at the second side, penetrates through the fourth copper-clad plate, the fourth prepreg and the third copper-clad plate and penetrates through the third signal layer.
The first back drilling hole can remove residual copper in the first through hole, the second back drilling hole can remove residual copper in the second through hole, and the transmission requirement of the secondary high-speed signal can be met.
Optionally, forming the plurality of blind holes includes: forming a plurality of blind holes through a laser hole process or a mechanical hole process; forming a plurality of through holes through the high speed printed circuit board includes: a plurality of through holes penetrating the high-speed printed circuit board are formed through a mechanical hole process.
The laser hole technology is to gasify or dissolve out the plate material to form holes by utilizing the plate material to absorb laser heat, and the mechanical hole technology is to drill holes through a mechanical drill bit.
The preparation method of the high-speed printed circuit board in the technical scheme of the embodiment of the invention can reduce the cost for preparing the high-speed printed circuit board and ensure the signal integrity.
It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present invention may be performed in parallel, sequentially, or in a different order, so long as the desired results of the technical solution of the present invention are achieved, and the present invention is not limited herein.
The above embodiments do not limit the scope of the present invention. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.
Claims (8)
1. A high speed printed circuit board comprising:
the copper-clad plates comprise conductive layers, insulating substrates and signal layers which are sequentially stacked;
a core plate including a support substrate and two conductive layers respectively located on opposite side surfaces of the support substrate; the core board is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates are symmetrically arranged on the first side and the second side of the core board;
the prepregs are positioned between the copper-clad plate and the core plate and between the adjacent copper-clad plates;
the blind holes are positioned on the first side, and penetrate through the copper-clad plate positioned on the first side and farthest from the core plate to the signal layer on the first side;
a plurality of through holes including back holes, the through holes penetrating the high speed printed circuit board; the back drilling hole is positioned on the second side of the core plate, and penetrates through the signal layer on the second side from the copper-clad plate positioned on the second side and farthest from the core plate;
the signal layer includes: a high-speed signal layer and a second high-speed signal layer;
the high-speed signal layer is positioned in the copper-clad plate at the first side of the core plate;
the secondary high-speed signal layer is positioned in the copper-clad plate at the second side of the core plate.
2. The high-speed printed circuit board of claim 1, comprising:
the first copper-clad plate, the first prepreg, the second copper-clad plate, the second prepreg, the core plate, the third prepreg, the third copper-clad plate, the fourth prepreg and the fourth copper-clad plate are sequentially stacked; the first copper-clad plate and the fourth copper-clad plate are symmetrically arranged, the second copper-clad plate and the third copper-clad plate are symmetrically arranged, the first copper-clad plate comprises a first signal layer, the second copper-clad plate comprises a second signal layer, the third copper-clad plate comprises a third signal layer, the fourth copper-clad plate comprises a fourth signal layer, the first signal layer and the second signal layer are high-speed signal layers, and the third signal layer and the fourth signal layer are secondary high-speed signal layers;
the first blind hole is positioned at the first side, penetrates through the first copper-clad plate and penetrates through the first signal layer;
the second blind hole is positioned on the first side, penetrates through the first copper-clad plate, the first prepreg and the second copper-clad plate and penetrates through the second signal layer;
a first through hole including a first back-drilled hole, the first through hole penetrating the high-speed printed circuit board; the first back drilling hole is positioned at the second side, penetrates through the fourth copper-clad plate and penetrates through the fourth signal layer;
a second through hole comprising a second back-drilled hole, the second through hole penetrating the high-speed printed circuit board; the second back drilling hole is located at the second side, penetrates through the fourth copper-clad plate, the fourth prepreg and the third copper-clad plate and penetrates through the third signal layer.
3. The high-speed printed circuit board according to claim 1, wherein the aperture of the blind hole is 0.1mm, and the aperture of the through hole is not less than 0.2mm.
4. A method of manufacturing a high-speed printed circuit board, comprising:
forming a plurality of copper-clad plates, wherein the copper-clad plates comprise conducting layers, insulating substrates and signal layers which are sequentially stacked;
forming a core plate, wherein the core plate comprises a supporting substrate and two conductive layers respectively positioned on two opposite side surfaces of the substrate;
forming prepregs between two adjacent copper-clad plates on the first side of the core plate for lamination, and forming a plurality of blind holes on the first side of the core plate; the blind holes penetrate through the signal layer at the first side from the copper-clad plate at the first side, which is farthest from the core plate;
forming prepregs between two adjacent copper-clad plates on the second side of the core plate and between the core plate and the copper-clad plates on the two sides for lamination, and forming a plurality of through holes penetrating through the high-speed printed circuit board; the core board is positioned at the middle position of the high-speed printed circuit board along the thickness direction, and the copper-clad plates are symmetrically arranged on the first side and the second side of the core board;
forming a back-drilled hole in the through-hole; the back drilling hole is positioned on the second side of the core plate, and penetrates through the signal layer on the second side from the copper-clad plate positioned on the second side and farthest from the core plate;
the signal layer includes a high speed signal layer and a next highest speed signal layer, forming the signal layer includes:
forming the high-speed signal layer in the copper-clad plate at the first side of the core plate;
and forming the secondary high-speed signal layer in the copper-clad plate at the second side of the core plate.
5. The method for manufacturing a high-speed printed circuit board according to claim 4, wherein the high-speed printed circuit board comprises a first copper-clad plate, a first prepreg, a second copper-clad plate, a second prepreg, a core plate, a third prepreg, a third copper-clad plate, a fourth prepreg and a fourth copper-clad plate which are sequentially stacked; forming a prepreg between two adjacent copper-clad plates on the first side of the core plate for lamination, and forming a plurality of blind holes on the first side of the core plate, comprising:
forming a first blind hole in the first copper-clad plate; the first blind hole penetrates through the first copper-clad plate and penetrates through the first signal layer; the first copper-clad plate comprises a first signal layer;
forming a first prepreg on the first copper-clad plate;
laminating the first copper-clad plate and the second copper-clad plate through the first prepreg; the second copper-clad plate comprises a second signal layer, and the first signal layer and the second signal layer are the high-speed signal layers;
forming a second blind hole in the second copper-clad plate; the second blind hole penetrates through the first copper-clad plate, the first prepreg and the second copper-clad plate and penetrates through the second signal layer.
6. The method of manufacturing a high-speed printed circuit board according to claim 5, wherein forming prepregs between two adjacent copper-clad plates on the second side of the core board and between the core board and the copper-clad plates on both sides for lamination, and forming a plurality of through holes penetrating the high-speed printed circuit board, comprises:
disposing a second prepreg on the first side surface of the core board, and forming a third prepreg on the second side surface;
the third copper-clad plate is arranged on the third prepreg; the third copper-clad plate comprises a third signal layer;
forming a fourth prepreg on the third copper-clad plate;
a fourth copper-clad plate is arranged on the fourth prepreg, the third copper-clad plate and the fourth copper-clad plate are pressed on the second side of the core plate through the third prepreg and the fourth prepreg, and the pressed first copper-clad plate and second copper-clad plate are pressed on the first side of the core plate through the second prepreg; the first copper-clad plate and the fourth copper-clad plate are symmetrically arranged, the second copper-clad plate and the third copper-clad plate are symmetrically arranged, the fourth copper-clad plate comprises a fourth signal layer, and the third signal layer and the fourth signal layer are the secondary high-speed signal layer;
first and second through holes are formed through the high speed printed circuit board.
7. The method of manufacturing a high-speed printed circuit board according to claim 6, wherein forming a back-drilled hole in the through-hole comprises:
forming a first back borehole in the first via; the first back drilling hole is positioned at the second side, penetrates through the fourth copper-clad plate and penetrates through the fourth signal layer;
forming a second back borehole in the second via; the second back drilling hole is located at the second side, penetrates through the fourth copper-clad plate, the fourth prepreg and the third copper-clad plate and penetrates through the third signal layer.
8. The method of manufacturing a high-speed printed circuit board of claim 4, wherein forming the plurality of blind vias comprises:
forming a plurality of blind holes through a laser hole process or a mechanical hole process;
forming a plurality of through holes through the high speed printed circuit board includes:
and forming a plurality of through holes penetrating through the high-speed printed circuit board through a mechanical hole process.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310904379.8A CN116634662B (en) | 2023-07-24 | 2023-07-24 | High-speed printed circuit board and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310904379.8A CN116634662B (en) | 2023-07-24 | 2023-07-24 | High-speed printed circuit board and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116634662A CN116634662A (en) | 2023-08-22 |
| CN116634662B true CN116634662B (en) | 2023-10-10 |
Family
ID=87603005
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310904379.8A Active CN116634662B (en) | 2023-07-24 | 2023-07-24 | High-speed printed circuit board and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116634662B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112822878A (en) * | 2021-01-31 | 2021-05-18 | 惠州中京电子科技有限公司 | Manufacturing method of variable-frequency high-speed printed circuit board |
| CN114040580A (en) * | 2021-11-08 | 2022-02-11 | 珠海杰赛科技有限公司 | Manufacturing method of universal blind slot plate |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9003648B2 (en) * | 2007-01-02 | 2015-04-14 | Ormet Circuits, Inc. | Methods to produce high density, multilayer printed wiring boards from parallel-fabricated circuits and filled vias |
-
2023
- 2023-07-24 CN CN202310904379.8A patent/CN116634662B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112822878A (en) * | 2021-01-31 | 2021-05-18 | 惠州中京电子科技有限公司 | Manufacturing method of variable-frequency high-speed printed circuit board |
| CN114040580A (en) * | 2021-11-08 | 2022-02-11 | 珠海杰赛科技有限公司 | Manufacturing method of universal blind slot plate |
Also Published As
| Publication number | Publication date |
|---|---|
| CN116634662A (en) | 2023-08-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5658399B1 (en) | Printed wiring board | |
| CN102387672B (en) | Method for manufacturing multilayer circuit board | |
| CN103456643A (en) | Ic carrier plate and manufacturing method thereof | |
| JP5165265B2 (en) | Manufacturing method of multilayer printed wiring board | |
| CN103260350B (en) | Blind buried via hole plate compression method | |
| CN110167289B (en) | Method for manufacturing multilayer circuit board | |
| CN103052281A (en) | Embedded multilayer circuit board and manufacturing method thereof | |
| KR20060062896A (en) | Parallel mlb granted interlayer conductivity by viapost and method thereof | |
| EP1802187A2 (en) | Printed circuit board and manufacturing method thereof | |
| CN211063845U (en) | Mechanical blind hole HDI circuit board | |
| US6372999B1 (en) | Multilayer wiring board and multilayer wiring package | |
| CN116634662B (en) | High-speed printed circuit board and preparation method thereof | |
| JP4485975B2 (en) | Manufacturing method of multilayer flexible circuit wiring board | |
| CN104349610A (en) | Manufacturing methods of printed circuit board daughter board and printed circuit board, and printed circuit board | |
| JP2019071318A (en) | Multilayer wiring board and manufacturing method therefor | |
| KR100975927B1 (en) | Method of manufacturing package board | |
| JP2017069318A (en) | Multilayer wiring board | |
| CN104284530A (en) | Method for manufacturing printed circuit board or integrated circuit package substrate through coreless board process | |
| JP2517315B2 (en) | Electronic circuit package | |
| JPS5987896A (en) | Multilayer printed board | |
| US11122674B1 (en) | PCB with coin and dielectric layer | |
| JP2019029559A (en) | Multilayer wiring board and manufacturing method thereof | |
| JP4302045B2 (en) | Multilayer flexible circuit wiring board and manufacturing method thereof | |
| JP4233528B2 (en) | Multilayer flexible circuit wiring board and manufacturing method thereof | |
| JP4397793B2 (en) | Circuit board and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |